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Exercising the brain to prevent cognitive decline or improve focus is becoming a more common activity in today's society with applications and web pages, such as, for example, Lumosity.com. The applications are generally about stimulating the neural pathways in parts of the brain attributable to memory or focus in such a way as to strengthen and reinforce existing neural connections. The theory of brain training, in part, relies on the fact that the human brain remains plastic and creates new connections through increased stimulation of the relevant pathways.
In certain recent studies, it has been discovered that the brain tends to “think” and “pay attention” to events (actions, sounds, sensations, tastes, visuals) that produced a pleasurable or rewarding experience in the past. For simplicity, pleasurable or rewarding will be consider events (as broadly defined) that stimulate the brain to produce dopamine and other neurochemical reactions associated with pleasure or reward. In lay terms, these may be considered “feel good” activities.
Researchers at John Hopkins University conducted a study with a small sample of participants. The participants were instructed that they would be rewarded (money in this case) for certain behavior. The reward would be X for identifying “green” objects on a computer screen and 6X for identifying “red” objects on the same computer screen. The next day, the same participants were ask to find certain shapes on the screen but color was no longer relevant for the activity. The participants' brain activity was monitored using positron emission tomography (“PET”). Because of the previously associated large reward for the discovery of red objects, the research identified that the participants tended to focus on the red objects even though no reward was in fact contemplated by the on-going study. The research identified that the participants focus on red was unconscious, and the brain was stimulated by dopamine (and possibly other neuro chemical reactions associated with pleasure) when the red objects appeared.
The research further identified that the higher the dopamine or the like in the brain based on the previously rewarded behavior, the harder it was for the participant to complete the new or repurposed task. In other words, when a person sees or experiences something associated with a past reward, his/her brain flushes with dopamine unconsciously and regardless of an expectation of a reward. Because of the neurochemical reaction, the brain focuses on the event causing the reaction regardless of the conscious effort of the individual.
Such unconscious activity indicates that self-control is more difficult in activities associated with previously rewarding experiences. The research also suggests why, among other things, it may be more difficult to maintain a diet for extended periods of time or break an addiction.
The study concluded that there was an opportunity to attempt to develop a pharmaceutical to curb the neurochemical reactions associated with rewards or pleasure based on past experiences. Use of pharmaceuticals, however, may have unintended consequences including, for example, depression or the like. Thus, against this background, it would be desirous to develop systems and methods to disassociate the memory of a reward with events or objects. | {
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This invention is generally directed to photoresponsive devices; and more specifically the present invention is directed to photoresponsive devices, comprised of organic or inorganic materials and silicone ammonium salts. The photoresponsive devices of the present invention are useful in electrostatographic imaging systems, particularly xerographic systems.
Overcoated photoresponsive devices containing protective top coatings, such as silicone resins are known. These protective coatings, have been found to be highly useful when applied to various organic and inorganic photosensitive materials, such as amorphous selenium. However, in many instances, these silicone resin overcoatings have a tendency to separate from the photoconductive material primarily because of their poor adhesion properties. While adhesive materials have been developed for permanently adherring top coatings such as silicone resins to photoreceptor devices, the coatings continue to separate over extended periods of usage. Additionally, it is important that adhesive materials be employed that possesses an electrical conductivity of sufficient value so as to maintain a zero to low residual potential in the photoresponsive device.
Abrasion resistant resins, such as organothiol siloxanes, and alkylene-alkoxy silane resins are disclosed in various prior art patents including U.S. Pat. Nos. 3,986,997, 4,177,175, 4,127,697, and 4,239,668. The organothiol siloxanes however, are known to suffer from a number of disadvantages. For example, these materials require high temperatures to achieve activation, and thus are of substantially little value for use at room temperatures. Additionally, in most instances, these siloxanes have undesirable odors. Further, compositions containing such siloxanes have undesirable high residual potentials when, for example, they are utilized in overcoated photoresponsive device. Also, the use of known amino silanes as adhesives or primers for photoresponsive devices, such as those disclosed in U.S. Pat. No. 4,127,697, can cause the formation of high residual potentials in these devices.
Accordingly, there continues to be a need for new adhesive materials, and particularly adhesive materials which can be utilized in photoresponsive devices for the purpose of bonding protective coatings, such as silicone resins, to the photoreceptor surface. Additionally, and more importantly there continues to be a need for adhesive materials which possess an electrical conductivity of certain valves, that is from about 10.sup.8 to about 10.sup.-- (ohm-cm).sup.-1 in order that a zero to low residual potential can be maintained on the photoreceptor surface. | {
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1. Field of the Invention
This invention relates to improved connection between electrical cords. More particularly, it relates to an accessory for holding two electrical cords in connection and preventing their accidental disconnection.
2. Description of Background Art
There is a need for a simple, inexpensive, practical device to maintain the separable elements of an extension cord coupling against inadvertent separation. Frequently, the electrical cords of typical electrical equipment such as vacuum cleaners, hedge trimmers, industrial machinery such as hand drills, extension lights and the like, must be coupled to an extension cord to reach their desired location of use. The inherent strength of the coupling brought about by the friction between the prongs of one plug on the first cord and their corresponding receptacle on the second cord generally will not hold anything but the most moderate separating tension. This property is built into common household cords.
One solution to this has been the use of "twist-lock" connectors. These find acceptance in heavy-duty industrial and theatrical settings. "Twist-lock" connectors employ special prongs and receptors which are not compatible with normal home or light industrial wall plugs or with the connectors on normal extension cords. Accordingly, this solution, while effective in an industrial setting, does not work in many more common applications.
An alternative solution to the problem of cord separation has been to equip the connection with an appliance or accessory which holds the two ends of the connection in engagement. U.S. Pat. No. 3,383,639 to Anderson et al. shows a clamp device which fits around the two ends of a connection and holds the two connector halves in connection. Although this device has the advantage of being easy to use, it requires complete removal when the plugs are separated.
U.S. Pat. No. 3,014,194 to Berglund shows a cable connector protector which is a single body which clamps around the connected plug.
U.S. Pat. No. 3,030,601 to Krebs shows a very simple device which is a one-piece jacket formed of a rubberlike material which slips around the plugged-together cables.
U.S. Pat. No. 4,169,643 to Gallagher shows a mating clip wherein the connected ends of the receptacle and plug are latched within a closable container.
U.S. Pat. No. 4,643,505 to House, et al. shows a similar device in which a latched-together connector is clamped within a housing to secure its connection.
U.S. Pat. No. 4,690,476 to Morgenrath discloses an electrical connector securing system where each end of the coupling is equipped with a housing and the two housings are held together by straps.
U.S. Pat. No. 4,784,612 to Ryan discloses a pair of housings, one on each half of the connector, which thread together to secure the connector halves in a connected state.
All of these references suggest that there is a need for a good, efficient, inexpensive device for positively locking together electrical cords to prevent their uncoupling during use. Ideally, the device should be easy to engage and disengage while assuring the integrity of the connection when engaged. Also it is desirable if the locking device remains connected with the cord ends to prevent its accidental loss when not in use. Accordingly, it is an object of this invention to provide a simple and inexpensive device for securing together a pair of electrical plugs and to overcome the disadvantages associated with known devices of this type. | {
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Hereinafter, Radio frame structures used in 3rd Generation Partnership Project (3GPP) Release 8 (referred to as Long Term Evolution (LTE)) and subsequent releases will be described, and then carrier aggregation (CA) introduced in 3GPP Release 10 (which is referred to as LTE-Advanced) will be described. Further, Licensed Assisted Access (LAA) and Licensed Shared Access (LSA), which are currently being discussed in regard to 3GPP Release 13, will be described.
Firstly, LTE radio frame structures will be described. In 3GPP Release 8 and subsequent releases, two types of the radio frame structures are specified. One is referred to as a frame structure type 1, which is applied to frequency division duplex (FDD). The other one is referred to as a frame structure type 2, which is applied to Time division duplex (TDD). As shown in FIG. 16, in both frame structure type 1 and frame structure type 2, the length of one radio frame is 10 milliseconds and one radio frame consists of 10 subframes. In the case of TDD, the first five subframes (#0 to #4) and the last five subframes (#5 to #9) are each referred to as a half-frame. The length of one half-frame is 5 milliseconds. The length of one subframe is 1 millisecond. One subframe is divided into two slots of 0.5 milliseconds each. In the case of Normal cyclic prefix, one slot includes seven symbols (i.e., single carrier frequency division multiple access (SC-FDMA) symbols in uplink, and orthogonal frequency division multiplexing (OFDM) symbols in downlink) in the time domain. Accordingly, one subframe includes 14 symbols in the time domain.
Moreover, 3GPP Release 10 has specified the Carrier Aggregation (CA) function that enables a radio terminal (User Equipment: UE) to communicate with a radio base station (eNode B: eNB) and using a plurality of cells. Cells available to a UE in CA are limited to a plurality of cells of a single eNB (i.e., cells operated or managed by an eNB). The cells used by the UE in CA are categorized into a primary cell (PCell) that has already been used as a serving cell when CA is started and secondary cell(s) (SCell(s)) that is used additionally or in a dependent manner. In the PCell, when a radio connection is (re-)established (Radio Resource Control (RRC) Connection Establishment, RRC Connection Re-establishment), Non Access Stratum (NAS) mobility information and security information (security input) are transmitted (see Section 7.5 of Non Patent Literature 1).
From a functional point of view, the introduction of CA has enabled high-speed communication. In practical usage, however, it is considered that it would be difficult to address the issue of a further increase in mobile traffic in the future due to limitations (shortage) of frequencies allocated to each operator. Accordingly, in the 3GPP standardization process, discussions on Unlicensed LTE that executes LTE with the use of an unlicensed frequency (unlicensed frequency band, unlicensed spectrum) have been started (Non-Patent Literature 2 and 3). Unlicensed LTE is also referred to as LTE-U or U-LTE and is hereinafter referred to as LTE-U.
As methods for achieving LTE-U, two methods, i.e., Licensed Assisted Access (LAA) in which the eNB performs communication with the UE on the unlicensed frequency in association with the licensed frequency (e.g., as SCell of CA) and Standalone (SA) in which the eNB performs communication with the UE only on the unlicensed frequency, are considered. The unlicensed frequency is, for example, 5 GHz band, which is also used by other systems such as radar systems and wireless LAN (WLAN or also referred to as WiFi). Therefore, with regard to the SA scheme in which communication is performed only on the unlicensed frequency, it would be difficult to implement sophisticated controls specified for LTE and thus the more feasible LAA scheme (also referred to as LA-LTE) has mainly been discussed. In the following description, LTE-U by the LAA scheme, in which CA using the licensed frequency and the unlicensed frequency is performed, will be mainly explained. The licensed frequency means a dedicated frequency allocated to a specific operator. The unlicensed frequency means a frequency that is not allocated to a specific operator or a shared frequency allocated to a plurality of operators. In the latter case, this frequency may be referred to as a licensed shared frequency, not an unlicensed frequency, and communication using this frequency is also referred to as a Licensed Shared Access (LSA). In the following description, frequencies other than licensed frequencies licensed only to any specific operators are collectively referred to as an unlicensed frequency.
LTE-U by the LAA scheme is executed basically in accordance with the sequence shown in FIG. 17. In this example, it is assumed that an eNB performs data transmission (or reception) with a UE #1 in a Cell #1 on a licensed frequency and in a Cell #2 on an unlicensed frequency. Firstly, a radio connection is established between the eNB and UE #1 in the Cell #1 (RRC Connection Establishment, 1501), and a bearer is established between a core network (Evolved Packet Core: EPC) and the UE #1 (not shown). That is, the Cell #1 is a PCell for the UE #1. When there is downlink (DL) user data (also referred to as User Plane (UP) data) to be transmitted to the UE #1 or there is uplink (UL) user data that the UE #1 wants to transmit, the eNB transmits or receives this user data in the Cell #1 (DL (or UL) UP data transmission, 1502).
Next, when the eNB determines that it is efficient for the UE #1 to transmit and receive the user data in the Cell #2 at some point (Trigger LTE-U for UE #1, 1503), the eNB transmits to the UE #1, in the Cell #1, control information about radio resource configuration for the Cell #2 (Radio Resource Configuration for Cell #2, 1504). This control information corresponds to a RadioResourceConfigDedicated Information Element (IE) and a RadioResourceConfigCommon IE transmitted in an RRC Connection Reconfiguration message of LTE (Non Patent Literature 4). The Cell #2 hereby becomes an SCell for the UE #1. When the user data is transmitted in the downlink, the eNB performs sensing in the Cell #2 to determine whether the Cell #2 is available (Perform channel sensing, 1505). Upon determining that the Cell #2 is available, the eNB transmits or receives the user data to or from the UE #1 (DL (or UL) UP data transmission, 1506). As described above, through the use of the unlicensed frequency, it is expected that the throughput will be further improved or the cell capacity will be increased.
The aforementioned sensing is referred to as Listen Before Talk (LBT) (Non-Patent Literature 2), which determines whether LTE-U by another operator or communication of another radio system (e.g., WLAN) is performed nearby on the target unlicensed frequency. The aforementioned sensing corresponds to, for example, Channel Availability Check (CAC) for radar systems and Clear Channel Assessment (CCA) executed by a WLAN Access Point (AP) (Patent Literature 1). | {
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1. Field of the Invention
The present invention relates to a non-invasive method for estimating of the variation of the glucose level ΔG in the blood of a person and to an apparatus for carrying out the method.
2. Description of the Prior Art
At present, a variety of methods and devices for the non-invasive estimation of blood glucose level are known: laser-light scattering and absorption, combinational (Raman) scattering (U.S. Pat. Nos. 7,054,514, 7,454,429, 5,448,992), nuclear magnetic resonance (NMR) methods (U.S. Pat. No. 7,295,006) and impedance spectroscopy (patents US 2002/0155615, RU 2001/115028). The measuring devices based on such technologies have and most likely will still have a high prime cost and hence a high price non-affordable for an individual consumer.
As affordable and thus promising methods for mass consumption, despite of, strictly speaking, indirect character of blood glucose level estimation, impedance or conductometry methods have been considered. Such methods postulate the presence of a connection between the electrical quantities of tissues and the glucose concentration in blood. However, electric parameters of native tissues are directly dependent not only on glucose or other substances maintenance, but also on the condition of their hydration. Despite of all such known physiological mechanisms, there are still no good and reliable non-invasive glucometers working on the basis of a conductivity measurement. | {
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(a) Field of the Invention
The present invention relates to a transflective liquid crystal display (LCD) device including a transmissive area and a reflective area in each pixel of the LCD device.
(b) Description of the Related Art
LCD devices are generally categorized in two types: a transmissive LCD device having therein a backlight unit as a light source; and a reflective LCD device having therein a reflection film which reflects external light incident onto the LCD device and thus functions as a light source. The reflective LCD device has the advantages of lower power dissipation, smaller thickness and lighter weight compared to the transmissive LCD device, due to absence of a backlight source in the reflective LCD device. On the other hand, the transmissive LCD device is superior to the reflective LCD device in that the transmissive LCD device can be well observed in a dark environment.
There is another type of the LCD device, known as a transflective LCD device, which has the advantages of both the reflective and transmissive LCD devices. Such a transflective LCD device is described in Patent Publication JP-A-2003-344837A, for example. The transflective LCD device includes a transmissive region (or transparent region), and a reflection region in each pixel of the LCD device. The transmissive region passes light emitted from a backlight source, and uses the backlight source as a light source. The reflective region includes a rear reflective plate or reflection film, and uses external light reflected by the reflection film as a light source.
In the transflective LCD device, the image display is performed by the reflective region in a well-lighted environment, with the backlight source being turned OFF, thereby achieving a smaller power dissipation. On the other hand, the image display is performed by the transmissive region in a dark environment, with the backlight source being turned ON, thereby achieving an effective image display in the dark environment.
In general, a variety of modes are used for operating LCD devices, including an in-plane-switching (IPS) mode, a twisted-nematic (TN) mode, and a fringe-field-switching (FFS) mode. Each pixel of the IPS-mode or FFS-mode LCD device includes a pixel electrode and a common electrode which are disposed on a common substrate to apply the liquid crystal (LC) layer with a lateral electric field. The IPS-mode or FFS-mode LCD device using a lateral electric field rotates the LC molecules in a plane parallel to the substrate to perform the image display, and achieves a higher viewing angle compared to the TN-mode LCD device.
If the IPS mode or FFS mode using a lateral electric field is to be employed in the transflective LCD device as described above, there arises an image-inversion problem in the LCD device, as described in the patent publication as mentioned above. More specifically, in a normal driving technique of the LCD device, if the transmissive region operates in a normally-black mode wherein absence of the applied voltage corresponds to a dark state, the reflective region operates in a normally-white mode wherein absence of the applied voltage corresponds to a bright state. The reason of the image-inversion problem will be described in detail hereinafter.
FIG. 34A schematically shows a pixel of a transflective LCD device, which includes therein a reflective region 55 and a transmissive region 56. The transmissive region 56 is configured by a first polarizing film 51, a first substrate (counter substrate) 61, a LC layer 53 having a retardation of λ/2, a second substrate (TFT substrate) 62, and a second polarizing film 52, which are arranged in this order as viewed from the front of the LCD device 50, wherein λ is a wavelength of the light. The reflective region 55 is configured by the first polarizing film 51, first substrate 61, LC layer 53 having a retardation of λ/4, an insulation film 63, and a reflection film 54, effective constituent elements. In FIG. 34A, polarizing axis of the polarizing films 51, 52, longer axis of the LC molecules in the LC layer 53 are depicted in the state wherein the LCD device is rotated by 90 degrees along a plane normal to the sheet of the drawing in the counterclockwise direction as viewed from the left of the drawing.
FIG. 34B shows polarization of light in the respective regions 55, 56 in FIG. 34A for the case of presence (Von) and absence (Voff) of the applied voltage, in the portions wherein the light passes through the first polarizing film 51, LC layer 53 and second polarizing film 52. In FIG. 34B, an arrow means linearly-polarized light, “L” encircled by a circle means counterclockwise-circularly-polarized light, “R” encircled by a circle means clockwise-circularly-polarized light, blank elongate bar means the director of the LC, i.e., longer axis of the LC molecules. FIG. 35 shows a sectional view of this type of the practical LCD device, the principle of which is shown in FIGS. 34A and 34B, including a backlight source 57.
In the LCD device 50a shown in FIG. 35, the reflective region 55 uses the reflection film 54 as the light source, whereas the transmissive region 56 uses the backlight source 57 as the light source.
The first polarizing film 51 disposed at the front side of the LC layer 53 and the second polarizing film 52 disposed at the rear side thereof have respective polarizing axes, which are perpendicular to one another. The LC layer 53 includes LC molecules having a director which is 90 degrees deviated from the polarizing axis of the second polarizing film 52 upon absence of the applied voltage. Assuming that the polarizing axis of the second polarizing film 52 is directed at a reference direction (zero degree), for example, the polarizing axis of the first polarizing film 51 is directed at 90 degrees and the longer axis of the LC molecules in the LC layer 53 is also directed at 90 degrees. The zero-degree direction is shown as the lateral direction in FIG. 34B, and the 90-degree direction is shown as the vertical direction in FIG. 34B. The cell gap of the LC layer 53 in the transmissive region 56 is adjusted such that the retardation Δnd is equal to λ/2, whereas the cell gap of the LC layer 53 in the reflective region 55 is adjusted such that the retardation Δnd is equal to λ/4, given λ, Δn and d being wavelength of the light, refractive-index anisotropy and cell gap, respectively. As for λ, if the wavelength of green light is used as a reference, λ is 550 nm.
Operation of the LCD device shown in FIGS. 34A, 34B and 35 will be described hereinafter, for each case of absence and presence of the applied voltage in respective regions 55, 56.
(1) Reflective Region Upon Absence of Applied Voltage:
In the left column (Voff) of the reflective region 55 shown in FIG. 34B, a linearly-polarized light polarized at 90 degrees, i.e., 90-degree linearly-polarized light is incident onto the LC layer 53 after passing through the first polarizing film 51. Since the optical axis of the linearly-polarized light incident onto the LC layer 53 is aligned with the longer axis of the LC molecules, the 90-degree linearly-polarized light passes through the LC layer 53 as it is, and is then reflected by the reflection film 54. The linearly-polarized light does not change the state thereof in general after the reflection, as shown in FIG. 34B, and is again incident onto the LC layer 53 as the 90-degree linearly-polarized light. The 90-degree linearly-polarized light passes through the LC layer 53 as it is and is incident onto the first polarizing film 51, which has a polarizing axis at 90 degrees, passes the 90-degree linearly-polarized light as it is. Thus, absence of the applied voltage allows the reflective region to assume a bright state.
(2) Reflective Region Upon Presence of Applied Voltage:
In the right column (Von) of the reflective region 56 in FIG. 34B, the 90-degree linearly-polarized light passed by the first polarizing film 51 is incident onto the LC layer 53. The voltage applied to the LC layer 53 directs the longer axis of the LC molecules from zero degree to 45 degrees within the plane parallel to the substrates. The deviation of polarized direction of the incident linearly-polarized light from the longer axis of the LC molecules in the LC layer 53 by 45 degrees and the retardation of λ/4 change the 90-degree linearly-polarized light into a clockwise-circularly-polarized light after the reflection, which is incident onto the reflection film 54 and reflected thereby. The reflected light shifts to a counterclockwise-circularly-polarized light and is incident onto the LC layer 53. The counterclockwise-linearly-polarized light is changed by the LC layer 53 into a zero-degree linearly-polarized light and incident onto the first polarizing film 51. The polarizing film 51 having a polarizing axis at 90 degrees blocks the incident light, thereby representing dark state.
Thus, the reflective region 55 operates in a normally-white mode wherein absence of the applied voltage provides a bright state, whereas presence of the applied voltage provides a dark state.
(3) Transmissive Region Upon Absence of Applied Voltage:
In the left column of the transmissive region 56 shown in FIG. 34B, a zero-degree linearly-polarized light is passed by the second polarizing film 52 and incident onto the LC layer 53. Since this incident light has a polarized direction normal to the longer axis of the LC molecules in the LC layer 53, the incident light is passed by the LC layer 53 as it is, and is incident onto the first polarizing film 51 as the zero-degree linearly-polarized light. The first polarizing film 51 having a polarizing axis at 90 degrees blocks the incident light, thereby representing a dark state.
(4) Transmissive Region Upon Presence of Applied Voltage:
In the right column of the transmissive region 56 shown in FIG. 34B, a zero-degree linearly-polarized light is passed by the second polarizing film 52 and incident onto the LC layer 53. The voltage applied to the LC layer 53 directs the longer axis of the LC molecules from zero degree to 45 degrees within the plane parallel to the substrates. The deviation of polarized direction of the incident linearly-polarized light from the longer axis of the LC molecules in the LC layer 53 by 45 degrees and the retardation of λ/2 of the LC layer change the zero-degree linearly-polarized light into a 90-degree linearly-polarized light, which is incident onto the first polarizing film 51. The first polarizing film 51 having a polarizing axis at 90 degrees passes the incident light, thereby representing a bright state.
Thus, the transmissive region operates in a normally-black mode wherein absence of the applied voltage provides a dark state whereas presence of the applied voltage provides a bright state.
The image-inversion problem is a general problem common to the lateral-electric-field modes (IPS mode, FFS mode) and other LCD modes. However, as to the TN mode, horizontal-orientation mode (ECB mode) or vertical-alignment mode (VA mode), for example, the image-inversion problem may be solved using a circularly-polarized light as the incident light to the LC layer. For this purpose, the orientations of the first polarizing film and λ/4 wavelength film are deviated by 45 degrees from one another. However, if the incident light is a circularly-polarized light, the circularly-polarized light looses the sensitivity to the rotation of the LC molecules parallel to the substrates, and thus passes through the LC layer as the circularly-polarized light. Accordingly, the LCD device using the lateral electric field represents a dark state at any time irrespective of presence or absence of the applied voltage in either of the reflective mode and the transmissive mode. That is, the lateral-electric-field-mode LCD device cannot represent the image thereof by using such a λ/4 wavelength film.
As described above, the transflective LCD device has the problem that both the absence and presence of the applied voltage provide reversed images of bright state and dark state in each pixel. The patent publication as mentioned above solves this problem without using the λ/4 wavelength film, by using the arrangement shown in FIG. 35, wherein the polarizing axis of the first polarizing film 51 is 45 degrees deviated from the longer axis of the LC molecules in the LC layer 53, as shown on the left side of the drawing. In this case, the reflective region 55 operates in a normally-black mode, whereas the transmissive region 56 operates in a normally-white mode. In order for changing the transmissive region 56 to operate in a normally-black mode, a λ/2 wavelength film 58 is interposed between the second polarizing film 52 and the LC layer 53, the λ/2 wavelength film 58 having an optical axis at 135 degrees, which is perpendicular to the longer axis of the LC molecules in the LC layer 53.
By using the above configuration, in the front viewing angle, the λ/2 wavelength film 58 compensates the polarizing effect on the light by the LC layer 53 having a retardation at λ/2. Thus, the combination of the LC layer 53 and λ/2 wavelength film 58 provides a substantially similar polarized state for both the incident light and the reflected light. Accordingly, the light passed by the second polarizing film 52 and assuming a 90-degree linearly-polarized state remains in the same polarized state after passing through the λ/2 wavelength film 58 and LC layer 53, and thus cannot pass through the first polarizing film 51. In short, the λ/2 wavelength film 58 interposed between the LC layer 53 and the second polarizing film 56 allows the transmissive region 56 to operate in a normally-white mode.
In the LCD device 50a shown in FIG. 35, the polarized direction of the light incident onto the LC layer 53 is deviated from the parallel or normal direction of the longer axis of the LC molecules in the LC layer 53. This involves a significant leakage of light during display of a dark state, due to the wavelength dispersion characteristic of the retardation of the LC layer 53. In addition, the λ/2 wavelength film 58 itself has a wavelength dispersion characteristic, which also causes leakage light during display of a dark state.
It is to be noted that the image-inversion problem, wherein the transmissive region 56 and the reflective region operate in reverse normal modes, can be solved by inverting the polarity of the applied voltage between the transmissive region 56 and the reflective region 55. The inversion of the voltage polarity as used herein is such that absence of the applied voltage in the transmissive region 56 and presence of the applied voltage in the reflective region 55 are concurrently performed. However, this configuration is not known in the field of LCD devices. In addition, the problem encountered in such a configuration and the technique for solving the problem are also not known. | {
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Juicers/mixers are popular at the present time. However, the conventional juicer/mixer does not provide a double filtering effect, causing a large amount of foam on top of the juice. Also, the conventional juicer/mixer does not provide residue discharging effect, causing the user difficulties in removing the residue.
It is the purpose of the present invention, therefore, to mitigate and/or obviate the above-mentioned drawback in the manner set forth in the detailed description of the preferred embodiment.
An object of the present invention is to substantially eliminate defects or drawbacks encountered in the prior art described above.
Another object of the present invention is to provide an improved juicer/mixer having a double filtering effect to make the juice purer than a conventional juicer.
According to one aspect of the present invention, the juicer/mixer includes an actuating device for providing electrical power to a rotating shaft thereon, to which a squeezing housing device is engaged, thus allowing food to be processed in the squeezing housing device. The sqeezing housing device has a filter portion in a side wall thereof, a plurality of hole-like cutter blades on the bottom thereof, a transmission socket protruding outward from the bottom for engaging to the rotating shaft of the actuating device, a circular flange portion with a plurality of grids formed thereon. A barrel is mounted on the actuating device, having a second filter on the bottom thereof, while leaving a central hole allowing the protruding socket of the squeezing housing device to pass through and a side hole thereof providing an output path for the juice. A dreg outlet device is mounted on the barrel device having a circular side wall, inside which is formed a circular inner flange portion, and a dreg outlet. When the squeezing housing device is engaged to the actuating device, the circular flange portion thereof contacts with the inner flange portion of the dreg outlet device, such that a plurality of cells are formed by the grids on the circular flange portion of the squeezing housing device and the circular side wall of the dreg outlet device. A cap device having a dreg displacement switch engaged to a stopper therein is positioned above the squeezing housing device, with the stopper remaining in the squeezing housing means. When the dreg displacement switch is manually engaged, the stopper moves a predetermined distance, causing the stopper to almost come in contact with the side wall filter of the squeezing housing device. Consequently dregs are gathered on the side wall filter and forwarded to cells between the squeezing housing device and the dreg outlet device. The dregs on each cell are sent to the dreg outlet of the dreg outlet device by the centrifugal effect of the rotating squeezing housing device.
Other objects, advantages, and novel features of the invention will become more apparent from the following detailed description when taken in conjunction with the accompanying drawings. | {
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The electrophoretic effect is well known and has been the subject of many prior art patents and articles describing the effect. As described and discussed in the prior art, the electrophoretic effect operates on the principle that certain particles, when suspended in a medium, can be electrically charged and thereby caused to migrate through the medium to an electrode of opposite charge. Electrophoretic image displays (EPIDs) implement the electrophoretic effect to produce desired images. In prior art EPIDs, colored particles, which are charged either positively or negatively, are suspended in a dielectric fluid medium that is either clear or of a color which optically contrasts with the particles. The suspension is injected into a cell comprising two parallel screen electrodes, at least one of which is transparent. The colored particles are caused to migrate to, and impinge upon, one of the screen electrodes under the application of an electric field, thereby displacing the fluid medium at that electrode creating the desired image. When the polarity of the field is reversed, the colored particles migrate to the opposite screen electrode.
For suitable examples of such devices using the electrophoretic effect, reference is made to U.S. Pat. No. 4,732,830 entitled ELECTROPHORETIC DISPLAY PANELS AND ASSOCIATED METHODS and issued to Frank J. DiSanto et al. on Mar. 22, 1988. In this patent, there is disclosed an electrophoretic display apparatus which includes a planar transparent member having disposed thereon a plurality of vertically extending, electrically conductive lines defining a grid. A plurality of horizontally extending electrically conductive cathode lines are disposed on top of the vertical lines but are insulated therefrom by a thin insulating layer, thereby forming an XY matrix of electrodes. A conductive plate or anode is spaced above the line pattern and disposed therebetween in an electrophoretic dispersion of yellow submicron pigment particles in a dark colored suspension medium. The particles are transportable within the medium.
As earlier stated, the dielectric suspension consists of submicron particles of a suitable pigment element suspended in a fluid. Each of these particles is encapsulated by means of a charge control and wetting agent which interacts chemically with the particle to enable the particle to acquire an electrical charge. Providing the particles with an electrical charge is important in minimizing particle flocculation when the particles are suspended in the suspension medium and in producing electrophoretic motion.
Up until now, high density chlorinated solvents, such as carbon tetrachloride and tetrachloroethylene and the like, have been used to prepare pigment suspensions for EPIDs and the like. For example, in U.S. Pat. No. 4,655,897 entitled "ELECTROPHORETIC DISPLAY PANELS AND ASSOCIATED METHODS" issued to Frank J. DiSanto et al. on Apr. 7, 1987, tetrachloroethylene is used as a solvent in the preparation of a pigment suspension for EPIDs.
High density chlorinated solvents, in combination with low density solvents, allow density balancing between the EPID liquid medium and the medium's suspended image forming particles. Balancing is important as it allows a uniformly tinted image to be produced over the entire display panel.
In recent years, however, chlorinated solvents have been targeted by regulators because of their potentially harmful environmental effects and toxicity. As a result of this, it is anticipated that the use of chlorinated solvents will be subject to strict restrictions in the future. Hence, the search for alternative solvents, which will replace chlorinated solvents, is of great importance.
Liquids that are completely fluorinated are dense and colorless, and have the tendency to be relatively inert. A combination of a dense fluorinated solvent along with a less dense hydrocarbon liquid, produce a stronger solvent system which is suitable for making dielectric fluid suspensions for EPIDs and similar devices.
It is well known that most fluorinated materials have low surface tension. This characteristic causes fluorinated liquids to be difficult to use in applications involving the wetting of a hydrocarbon substrate, such as, with organic or inorganic pigment surfaces. Thus, agglomerations of pigment particles are difficult to disperse in a fluorinated medium. As such, a stable suspension cannot be formed and the performance of the resulting device is unacceptable.
One method for improving a dispersion's stability is to introduce a surfactant which preferentially adsorbs onto the pigment surface to lower the interfacial tension between the pigment surface and the medium for wetting, and provides a certain electrostatic or steric repulsion for long term stability.
Stabilization of a dielectric suspension depends upon the solubility of the surfactant in the medium and the interaction between the surfactant and the pigment surface. Consequently, selection of the correct surfactant for a particular solvent combination is critical in making a stable dielectric suspension for an EPID or like device.
It is, therefore, an object of the present invention to provide an environmentally acceptable dielectric suspension composition comprising a fluorinated solvent medium which exhibits excellent optical contrast, high electrophoretic speed, long operating lifetime, and good suspension stability in an EPID or other like device.
It is a further object of the present invention to provide a method for making an environmentally acceptable fluorinated dielectric suspension. | {
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Many electronic devices include security features to prevent unauthorized access. For example, an electronic device can include a biometric sensor configured to establish a user's identity by determining whether obtained biometric data matches known biometric data of an authorized user. A fingerprint imaging system is one example of a biometric sensor.
In many cases, the performance of a biometric sensor may be affected by the precision with which biometric data can be detected. Although increased precision may lead to improved security for the electronic device, it may also result in a physical reduction in the size of one or more components of the sensor. For example, a high-precision fingerprint imaging system may require smaller imaging sensors than low-precision imaging systems.
Furthermore, the quality of a signal obtained from physically smaller components is often negatively affected by the components' smaller size. For example, small imaging sensors may detect less image information than large imaging sensors, generating lower-amplitude signals that may be more sensitive to interference. In other cases, small imaging sensors may be more susceptible to signal distortion from environmental conditions (e.g., temperature, pressure, humidity, and so on) than larger imaging sensors.
To account for the lower signal quality that may be associated with smaller components, many high-precision biometric sensors require close physical proximity (e.g., less than a millimeter) to a user in order to obtain a signal of sufficient quality. In other cases, biometric sensors may require advanced signal processing capability, which may undesirably increase power consumption and processing delays of the system.
As a result, high-precision biometric sensors are often challenging to include within the housing of an electronic device. For example, a biometric sensor positioned within a millimeter of the exterior of a housing may be at substantial risk of impact damage. In other examples, advanced signal processing capability may not be conveniently implemented by an electronic device with limited power and/or processing resources.
Accordingly, there may be a present need for improved high-precision biometric sensors. | {
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Currently, fluid enclosures are designed and built independently of the fluid being stored, or of any storage material that would be inserted within the enclosure. In its simplest form, a conventional pressure vessel can be used to contain a fluid, such as a compressed gas or a liquefied gas. The pressure vessel must be designed to accommodate the maximum pressure of the fluid without failure. Such simple design approaches can be extended to incorporate a storage material by filling the pressure vessel with storage material. In this case, the pressure vessel must now withstand the fluid pressure, as well as the stress induced by the force of the storage material exerted on the internal pressure vessel walls. Presently, these vessels tend to be of a cylindrical shape.
When very small storage systems are required, or when irregular (i.e. non-cylindrical) shapes are called for, the overall approach of employing conventional pressure vessels becomes problematic. In order to contain the internal pressures and mechanical stresses induced by a storage material, wall thickness and material properties of the enclosure must be sufficient to prevent rupture. Material properties considered include tensile strength, ductility, material compatibility, enclosure geometry, stress factors, etc. As a result, the range of materials that can be used to construct the enclosure is limited, and only vessel geometries which do not overly amplify the internal pressures as enclosure stress can be considered.
Challenges to fluid enclosure design are amplified when incorporated in small systems, such as in a small or micro scale fuel cell. In small systems, fluid enclosure wall thickness consumes a significant portion of the volume of the enclosure. Prismatic shapes or irregular form factors are very difficult to utilize since they will bow outward under even modest fluid pressure. When absorbing materials (e.g. hydrides) are used, the mechanical strain on the internal tank walls can induce large stresses. | {
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1. Field of the Invention
The present invention relates generally to modeling systems having time varying elements, non-linear elements, or both types of elements and amongst other things to a method and system for generating reduced order models capable of being used in simulation of systems having time varying elements, non-linear elements, or both types of elements.
2. Background of the Invention
The increasing size, complexity, and integration level of wireless communications circuits makes accurate simulation of system level performance problematic. A challenging problem in the area of analog circuits is the simulation of clocked analog circuits like switching filters, switching power supplies, and phase-locked loops. These circuits are computationally expensive to simulate using conventional techniques because these kinds of circuits are all clocked at a frequency whose period is orders of magnitude smaller than the time interval of interest to the designer. Further, radio frequency circuits, mixed signal operation circuits and the like require modeling of not only analog circuits but the interaction of analog and digital circuits as systems and the interaction between the analog and digital circuits. These products require complex system-on-chip design and system integration, delivered in the tight and unforgiving time frames inherent to consumer markets. The realities of consumer-driven chip design and deployment are driving key considerations for designers, such considerations include that: (1) design costs and time are likely to dominate the decision-making process for system designers; (2) designs must be captured at the highest level of abstraction possible; (3) next-generation systems will need more medium-complexity systems than highly complex part types; and (4) chips will most likely be developed particular for platforms rather than being assembled from independently developed blocks of silicon functionality.
Model reduction refers to the procedure of automatic generation of system macromodels from detailed descriptions of circuits or systems. These macromodels can be used to perform rapid system level simulation of engineering designs that are too complicated to analyze at the detailed component level. The advantage of the reduction approach is that because the macromodels are generated from detailed physical descriptions of the system components, the influence of detailed physical effects can be included at the system level. Thus, an essential feature of reduction approaches is thorough control and assessment of approximation errors from formal analysis of the reduction algorithms. The problem of automated macromodel generation is interesting from the viewpoint of system level design because if small, accurate reduced order models of system component blocks can be extracted, then much larger portions of a design, or more complicated systems, can be simulated or verified than if the analysis were to have to proceeded at a detailed level. The prospect of generating the reduced model from a detailed analysis of component blocks is attractive because the influence of second order device effects or parasitic components on the overall system performance can be assessed. In this way overly conservative design specifications can be avoided.
There has been considerable recent interest, primarily in the context of simulation of electrical interconnect, in extracting low order models of lumped (often passive) components that are time invariant. There are many systems, however, that are not linear time-invariant (LTI) but can be accurately modeled as linear time varying (LTV). For example, if a nonlinear circuit model is linearized around a time-varying large signal, the resulting model is linear time-varying. In particular, many RF components (e.g., mixers and filters) are designed to have a near linear response in the signal path, but may have strongly nonlinear response to other excitations, such as the clock of a switched capacitor filter, or a mixer""s local oscillator. RF circuits, which have a fundamental period, can be further classified as periodic time varying linear (PTVL) systems. Such components are prime candidates for LTV model reduction. From the above description, it can be seen that in the real world, the set of circuits that can be accurately modeled as LTV is much larger than the set that can be described as LTI.
Most of the recent work on LTI model reduction has been based, implicitly or explicitly, on projection-based formulations. The reduced model is obtained from the full model by projecting the linear system into a subspace of lower dimension. The subspace chosen determines the approximation properties of the reduced model.
It is now generally accepted that in LTI systems, choosing the projection subspaces to be Krylov subspaces is effective and efficient. The efficiency arises because the Krylov subspaces are easily computed. The effectiveness of the approach is motivated by noting that projecting into a Krylov subspace corresponds to matching derivatives of the Laplace-domain transfer function (the moments). Methods based on multipoint rational approximations are known to be particularly efficient. Unfortunately, however, model reduction for time-varying systems appears to have received little attention. Balanced truncation approaches have been proposed, but it is unclear how to implement these techniques effectively.
An additional problem in circuit design includes the modeling of interconnect and parasitic effects that are pervasive in all types of designs including digital, analog, and mixed signal designs. The computational cost due to the size and complexity of these circuit models is a major bottleneck in the verification of these designs. Therefore, a technique to provide accurate and compact macromodels of these interconnect and parasitic effects in circuits will improve upon the overall design cycle time.
Two recent trends in integrated circuit designs have brought out the importance of interconnect and parasitic effects in design verification: the evolution towards submicron designs and the rapid growth of telecommunication/RF circuit designs. The combination of high frequencies and high packaging densities in these designs has quickly increased the size as well as the complexity of the circuit models for circuit simulation and timing verification. Therefore, there is a need for a general tool to provide accurate and compact reduced order macromodeling of these linear circuit models to significantly improve the throughput of circuit simulation as well as timing verification, which in turn will improve the total design cycle time.
Presently, algorithms for reduction of large-scale linear systems have been projection-based approaches. Algorithms such as PVL, Arnoldi methods, and PRIMA obtain reduced models by projecting the linear equations describing the LTI model system into a subspace of lower dimension. The subspace chosen determines the approximation properties of the reduced model. Most of the popular algorithms exploit the connection between Krylov subspaces and rational approximation to develop algorithms that have a known relationship to the frequency-domain characteristics of the system, for example, matching the transfer function and some of its derivatives at various points in the complex plane. Linear reduction algorithms are useful for many problems, for example, simulation of electrical interconnect and analysis of noise in RF systems, but fail totally in other contexts. For example, adjacent channel power ratio xe2x80x9cACPRxe2x80x9d is a figure of merit for the distortion properties of digitally modulated RF transmission systems and therefore by definition requires the utilization of nonlinear models. Microelectromechanical systems (xe2x80x9cMEMSxe2x80x9d) and power systems also require nonlinear macromodeling approaches. However, very few results are available for reduction of nonlinear systems.
In one embodiment, the present invention is directed toward a method for model reduction of systems that have time varying elements, which can be described by time varying differential equations. This method allows for automated extraction reduction reduced models for non-linear RF blocks, such as mixers and filters, that have a near linear signal path but may have strongly non-linear responses.
In another embodiment, the present invention is directed toward a method for model reduction of systems that have non-linear elements, which can be described by non-linear differential equations.
In a further embodiments, the present invention is directed toward a method for model reduction of systems that have non-linear and time varying elements, which can be described by time-varying non-linear differential equations. | {
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1. Field of the Invention
The present invention relates generally to cutting elements for rotary drill bits for subterranean drilling, and more specifically to cutting elements providing a controlled superabrasive contact area during a predominant portion of the useful life of the cutting element, as well as bits so equipped and methods of drilling therewith.
2. State of the Art
Rotary bits are the predominant type of drill bits employed for subterranean drilling to oil, gas, geothermal and other formations. Of the types of rotary bits employed, so-called fixed cutter or "drag" bits have garnered an ever-increasing market share over the past few decades. This market share increase is attributable to a number of factors, but significant ones must be acknowledged as the wide availability and performance of superabrasive cutting elements.
Superabrasive cutting elements in their present state typically take the form of a polycrystalline diamond compact (PDC) layer or "table" formed onto a supporting substrate, typically of a cemented or sintered tungsten carbide (WC), in a press under ultra-high pressure and temperature conditions. Other superabrasive materials are known, including thermally stable PDCs, diamond films, and cubic boron nitride compacts. The present invention has utility with cutting elements employing any superabrasive material.
Several physical configurations of superabrasive tables for cutting elements are known, including square, "tombstone" shape, and triangular. However, the most common shape is circular, backed by a circular substrate of like size. These circular superabrasive tables are usually formed substantially to size in a press, but may be cut from larger, disc-shaped blanks. The other referenced shapes are generally required to be cut from a larger, disc-shaped blank, thus generating a large volume of scrap, reducing yield during fabrication and increasing fabrication costs.
As can be seen in FIGS. 1 and 2 of the drawings, state-of-the-art, disk-shaped cutting element 10 includes a circular, PDC superabrasive table 12 of substantially constant depth mounted to a disk-shaped WC substrate 14. Superabrasive table 12 includes a cutting face 16, a cutting edge 18 at the periphery of cutting face 16, and a side 20 to the rear of cutting edge 18 (taken in the direction of cutting element travel, cutting face-first). Cutting element 10 would typically be oriented on a drill bit with at least a nominal negative backrake so that cutting face 16 "leans" away from the formation being drilled. As the cutting edge 18 and side 20 of superabrasive table 12 of cutting element 10 first contact the formation under application of weight on bit (WOB) at location 22 of cutting edge 18, it can be seen that the superabrasive contact area is extremely small in both longitudinal depth or thickness as well as width, in part due to the aforementioned backrake. Thus, for a given WOB, the responsive loading per unit surface area at the side 20 of superabrasive table 12 contacting the formation being drilled is extremely high.
Due to the circular shape of the superabrasive table 12, however, as the cutting element 10 begins to wear and a so-called "wear flat" forms at one side of cutting face 16, superabrasive table 12 and the WC substrate 14 therebehind, the contact area of the superabrasive material under WOB, or so-called Normal force applied along the axis of the drill string to which the bit is secured, increases markedly in width and therefore in total area. The increasing contact area consequently requires an increase in WOB to maintain cutting element loading in terms of load per superabrasive unit surface area in contact with the formation to continue an acceptable rate of penetration (ROP). However, as WOB increases, so does wear on the superabrasive table, as well as the likelihood of spalling and fracture damage thereto. In addition, the requirement to increase WOB may undesirably affect drilling performance in terms of reducing steerability of a bit, as well as precipitate stalling of a downhole motor when the torque required to rotate under excessive WOB is exceeded, with consequential loss of tool face orientation. As can readily be visualized by looking at the relative contact area widths at location 22, location 24 (as the cutting element is about 20% in diameter worn) and location 26 (as cutting element 10 is about 40% in diameter worn and typically approaching, if not well past, the end of its useful life), the superabrasive contact area may increase by more than an order of magnitude from the time a cutting element first engages a formation until the end of its useful life, thus requiring an attendant increase in WOB to maintain ROP in a given formation.
This undesirable increase in superabrasive contact area is present in conventional PDC cutting elements bearing constant-thickness superabrasive tables of about 0.030 inch thickness. However, as cutting elements bearing tables of greater thicknesses are developed, for example 0.070 inch and 0.100 inch uniform-thickness tables, the contact area increase is exacerbated. The increase in wear flat area for such PDC cutting elements of 13 mm (0.529 inch) diameter is illustrated in FIG. 9, wherein superabrasive contact area versus percentage of cutting face diametric wear is shown respectively by lines A, B and C for cutting elements of 0.030, 0.070 and 0.100 inch superabrasive table thickness. For each of the 0.030 inch, 0.070 inch and 0.100 inch thickness tables, the contact area more than doubles between 5% and 30% diametric wear of the superabrasive table. More significantly, for the 0.070 inch and 0.100 inch thickness superabrasive tables, contact area quickly increases in absolute terms to in excess of 0.02 square inch (the maximum superabrasive contact area for a 13 mm, 0.030 inch thick table PDC cutting element), thus necessitating substantial and undesirable WOB increases extremely early in the life of the cutting element in order to maintain the load per unit surface area of superabrasive material contacting the formation. While use of a square or tombstone-shaped cutting face, would obviously provide a relatively constant superabrasive contact area, as noted above such configurations are undesirable for other reasons. Consequently, there is a need in the art for a cutting element exhibiting a circular cutting face and superabrasive table, the term "circular" as used herein including a segment of a circle a segment or which otherwise exhibits an arcuate or nonlinear cutting edge, which provides a relatively constant superabrasive contact area during a large portion of the useful life of the cutting element. | {
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Innovations in semiconductor fabrication and packaging technologies have enabled development of smaller scale, higher density integrated circuit chips, as well as the development of highly integrated chip modules with wiring and area array I/O contact densities that enable dense packaging of IC (integrated circuit) chips. In certain applications, high-performance electronic modules can be constructed with one or more MCMs (multi-chip modules) mounted to a circuit board such as a system board (or node card), a PCB (printed circuit board), a PWB (printed wiring board), etc, using a suitable area array connection technique for module-to-board I/O and power interconnections.
By way of example, high performance computer systems are typically designed with high-performance processor modules having first level packages (chip modules) constructed using MCM technology to achieve high-density packaging of large numbers of IC processor chips, as well as LGA technology to achieve high-density and high-count I/O interconnections to a second level package (e.g., node card).
Current MCM technology using glass-ceramic substrates can readily accommodate the higher I/O and power density requirements for compact, high performance package designs. In general, state of the art MCM techniques allow a plurality of IC chips to be flip-chip bonded to a ceramic module substrate using small pitch, highly dense arrays of micro-solder ball interconnects formed between bonding pads on the active surfaces of the IC chips and matching arrays of contact pads formed on a chip mounting surface on the ceramic substrate. For example, with glass-ceramic technology, high-density arrays of contact pads with on center contact pitches in the range of 0.15 to 0.25 mm, for example, can be formed on the top side substrate surface. Moreover, glass-ceramic MCM technology supports the wiring densities that are required for escape routing from the top side high-density contact arrays to, e.g., other chips on the substrate and to high density arrays of I/O contacts formed on the bottom side of the MCM substrate for module I/O and power.
For high-performance package designs, LGA techniques enable direct interconnection between corresponding area arrays of I/O contacts formed on mating surfaces of a chip module (e.g., Single Chip Module, SCM, or MCM) and circuit board using a conductive interposer that is compressed between the module and board. Various types of LGA interposer structures have been developed which generally include, for example, rigid, semi-rigid and flexible substrate structures having arrays of electrical contacts formed by, e.g., compressible conductive spring structures, conductive metal-elastomer composites, wadded wire, etc. State of the art LGA techniques enable MCM-to-board interconnections with I/O interconnect densities/counts and electrical/mechanical properties that are desirable for high-performance CPU module designs. Moreover, LGA interposers provide electrical and mechanical interconnect techniques that allow MCM chip modules to be readily removable from circuit boards, which is advantageous for high-end modules such as CPU (Central Processor Unit) packages which may require repeated rework during production or are designed to be field-upgradeable. FIGS. 1A˜1D schematically illustrate an electronic apparatus having a conventional LGA packaging structure for module-to-board I/O interconnection. FIG. 1A is a schematic cross-sectional side-view of an electronic apparatus (10) which generally comprises a chip module assembly (100), an LGA interposer (120), an electrical circuit board (130) and insulator layer (140) and a stiffener plate (150). The chip module assembly (100) comprises an MCM (multi-chip module) (110), a metallic support frame structure (104) and a thermal hat (105). The MCM (110) includes a module substrate (102) with a plurality of IC chips (103) flip-chip mounted to an array of contacts formed on the top surface of the substrate (102) via micro-solder balls (103a). The substrate (102) includes multiple levels of wiring and interconnects that provide electrical connections between top side contacts, other top side contacts, or an area array of I/O contacts (102a) formed on the bottom side of the substrate (102).
FIG. 1C is a schematic plan view of the bottom surface of the chip module assembly (100), which illustrates the bottom surfaces of the support frame (104) and the MCM substrate (102). The support frame (104) is designed to surround the perimeter of the MCM substrate (102). The support frame (104) includes various mechanical components (107) and (108) to support LGA alignment and actuation, as explained below. FIG. 1C illustrates a layout pattern of the I/O contacts (102a) on the bottom side of the substrate (102). In the exemplary embodiment, the area array of I/O contacts (102a) are arranged in 4 rectangular arrays (A1, A2, A3, A4) of evenly spaced metallized I/O pads, where the arrays are separately located in one of 4 quadrants on the bottom surface of the MCM substrate (102). FIG. 1D is an expanded view of a portion of the bottom surface of the chip module assembly (100) which includes the I/O contact array A1.
Referring again to FIG. 1A, the circuit board (130) includes an area array of contact pads (130a) on a top surface of the board (130) having a layout pattern matched to that of the area array of I/O contacts (102a) on the bottom of the MCM substrate (102). The board (130) includes conductive through vias (130b) formed within the board (130) below the contacts (130a). The board (130) includes multiple levels of wiring with connections to the conductive vias (130b) to thereby route I/O signals and power to the contacts (130a). The insulator sheet (140) electrically isolates the board (130) from the stiffener plate (150).
The LGA interposer (120) functions as a direct electrical interface to connect the I/O contacts (102a) on the bottom of the MCM substrate (102) to matching I/O contacts (130a) on the upper surface of the circuit board (130). FIG. 1B is a schematic side view illustration of the LGA interposer (120) of FIG. 1A. Referring to FIG. 1B, the LGA interposer (120) includes an insulating substrate (121) having an array (CA1) of columnar contact structures (122) aligned with corresponding I/O contacts (102a) on the bottom of the MCM substrate (102) and contacts (130a) on the top surface of the board (130). The LGA interposer (120) has a conventional framework based on conductive elastomer contact technology wherein the columnar contact structures (122) are formed of a composite of conductive metal particles embedded in a matrix of elastomer. Each columnar contact structure (122) includes an upper contact (122a) and a lower contact (122b), which are disposed on opposing surfaces of the substrate (121) and which are electrically connected through an aperture (122c) formed in the substrate (121). The contacts (122a) and (122b) are formed having larger heads on each side of the carrier (121) than the aperture (122c) such that each columnar contact (122) resembles a miniature rivet. The elastomer component of the contacts (122) provide the compliance that is needed to support the compressive force applied across each contact during LGA actuation, while accommodating possible nonplanar aspects of the mating surfaces. The electrical conductivity is provided by conductive fillers in the elastomer.
In general, the multichip module (110), LGA interposer (120), and circuit board (130) form a stacked structure, which is fixedly held together using a compression force applied by a hardware actuation structure to compress the LGA interposer (120) between the chip module (110) and board (130) with a force that is sufficient to ensure proper actuation of the LGA connectors (122). The support frame (104), package thermal hat (105) and stiffener plate (150) are mechanical components that serve various purposes including, e.g., mechanical support, thermal cooling, uniform loading of compression forces for LGA actuation, etc. For instance, the thermal hat (105) serves as a protective package lid as well as a heat spreader for cooling the IC chips (103). A thermal paste layer (106) is disposed between the back surface of the chips (103) and the thermal hat (105). The thermal paste (106) provides mechanical compliance and serves as a primary thermal path to transfer heat from the IC chips (103) to the thermal hat (105). An air cooled heat sink or a liquid cooled cold plate can be coupled to the thermal hat (105) to remove heat using known methods.
The metal support frame (104) serves to mechanically support the MCM (110), the thermal hat (105) and associated heat sink device mounted on top of the thermal hat (105). As shown in FIGS. 1A and 1B, the support frame (104) is designed to surround the outer perimeter of the MCM substrate (102). A silicone based adhesive is commonly used to bond a projection portion of the thermal hat (105) to the top surface of the MCM substrate (102) to form a semi-hermetic region around the ICs. Typically, the support frame (104) and the thermal hat (105) are bolted together.
The supporting frame (104) includes mechanisms to enable package assembly and LGA actuation. For instance, as shown in FIG. 1C, the support frame (104) includes alignment pins (107) which protrude from the bottom surface of the support frame (104) at two opposite corners thereof. These alignment pins (107) are aligned to, and mate with, alignment holes that are formed in the LGA interposer (120) and circuit board (130), to ensure proper alignment of I/O connections between the chip module (110) and board (130) through the LGA interposer (120). Moreover, hardware (108) is provided at the center of each side, for example, of the chip module assembly (100) as part of the LGA actuation structure.
Typically, LGA actuation is achieved using stiff springs which act to pull the MCM assembly (100) towards the stiffener plate (150) with a force that is sufficient to compress the LGA (120) between the MCM (110) and board (130). The supporting frame (104) and thermal hat (105) essentially form a top loading plate which acts to uniformly distribute the load around the top perimeter of the MCM substrate (102) which further distributes the load and the stiffener plate (150) is a bottom loading plate which acts to uniformly distribute the load across the system board (130), to thereby ensure uniform compression force across the LGA contact area. Only a minimal, if any, load is transferred through the thermal hat to the thermal paste layer and to the ICs (103) mounted on the MCM substrate (102).
FIGS. 1A˜1D illustrate a conventional package structure in which MCM and LGA technologies can be utilized to construct compact, high performance electronic modules, such as CPU modules, having highly-density chip modules with high density I/O module-to-board interconnections. For area array package structures such as depicted in FIG. 1A, the package footprint (i.e. MCM substrate (102) size) is based, primarily in part, on the number of I/O connections (I/O count) that are needed for a given design as well as the I/O contact density (I/O pitch). As chip modules are constructed with higher chip densities and functionality requiring higher I/O counts, the modules must be designed with smaller I/O pitch to either maintain or reduce the chip module footprint. In other words, smaller I/O pitch for the module-to-board interconnections allows higher-I/O-count chip modules to be formed using the same, or smaller, substrate sizes, thus lowering package costs.
Although current MCM and LGA interposer technologies can achieve high I/O densities (I/O pitch less than 1 mm), the I/O interconnect density in conventional package structures such as depicted in FIG. 1A has currently reached a practical pitch limit of 1 mm (e.g., P1 in FIGS. 1A and 1B). This limit is governed primarily by economics and manufacturing requirements of complex multilayer circuit board fabrication, which mandate the use of low-cost and high production/high yield board fabrication methods. However, state of the art board fabrication technologies (e.g., sequential lamination method) that meet such requirements are not able to provide the plated thru hole size and wiring densities needed to support I/O contact arrays having I/O pitch less than 1 mm. Although fine-pitch organic package technologies (e.g., “build-up” layers which are used in first level packages to which chips are directly attached) may be used in lieu of conventional PCB to construct system boards or node cards, it is too expensive to fabricate an entire system board or node card, for example, using such organic package technologies.
Consequently, in the package design of FIG. 1A, the I/O density is limited by the 1 mm contact pitch of the area array (130a) of the board (130). In this regard, the ability to use smaller scale MCM structures is effectively limited by the amount of electrical contacts needed to meet I/O and power requirements (bottom surface area) for the given application rather than the number and size of the chips (top surface area). As the number of I/O increases, if the I/O density cannot be increased, the MCM package size must be increased to accommodate more I/O contacts. Since MCM structures are very expensive to fabricate, it is desirable to increase the I/O available on the bottom surface of an MCM without increasing the MCM area and without decreasing the pitch of contacts on a PCB or node card or an LGA connector beyond practical limits. | {
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Field of the Invention
This invention relates to systems and methods for recovering from failures or shutdowns in log-structured object storage systems.
Background of the Invention
Storage systems that store objects (files, records, etc.) may be designed to either update the objects in place, or append objects to a log. Conventional object storage systems typically lay out objects for spatial locality and make in-place changes to the object data structures (e.g., by overwriting an object with an updated version of the object) in order to perform well on optical and magnetic disks, which tend to seek relatively slowly. Log-structured object stores, by contrast, may treat storage as a circular log wherein objects, as well as updates to the objects, are written sequentially to the tail of the log. In such systems, updates to an object are appended to the end of the log instead of being used to overwrite the object. An in-memory index may, in certain implementations, be used to locate the most recent version of objects in a log-structured object store. When an updated version of an object is appended to the log, the index may be updated to point to the updated version.
In log-structured object stores that use fully or partially in-memory indexes, the index may be periodically checkpointed to speed up recovery times in the event the index is lost due to a failure or shutdown. These checkpoints may be used to save or persist the in-memory index at the time of the checkpoint. However, high-performance log-structured object stores may support asynchronous write operations to improve utilization and performance. These asynchronous write operations may unfortunately cause stale checkpoints if the asynchronous write operations are not paused when the index is being checkpointed since the index may not reflect asynchronous operations that are in-flight and whose completion is not yet recorded in the index. A stale checkpoint may cause inconsistencies when recovering an in-memory index after a failure or shutdown. Although a log-structured object store may be read and analyzed from its beginning to reconstruct an in-memory index, this process can be overly time consuming and reduce performance.
In view of the foregoing, what are needed are systems and methods to more efficiently reconstruct in-memory indexes after a failure or shutdown. Ideally, such systems and methods will reduce time needed to restore operation of a log-structured object store after the failure or shutdown. | {
"pile_set_name": "USPTO Backgrounds"
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Pelvic health for men and women is a medical area of increasing importance, at least in part due to an aging population. Examples of common pelvic ailments include incontinence (e.g., fecal and urinary), pelvic tissue prolapse (e.g., female vaginal prolapse), and conditions of the pelvic floor.
Urinary incontinence can further be classified as including different types, such as stress urinary incontinence (SUI), urge urinary incontinence, mixed urinary incontinence, among others. Other pelvic floor disorders include cystocele, rectocele, enterocele, and prolapse such as anal, uterine and vaginal vault prolapse. A cystocele is a hernia of the bladder, usually into the vagina and introitus. Pelvic disorders such as these can result from weakness or damage to normal pelvic support systems.
Urinary incontinence can be characterized by the loss or diminution in the ability to maintain the urethral sphincter closed as the bladder fills with urine. Male or female stress urinary incontinence (SUI) generally occurs when the patient is physically stressed.
In its severest forms, vaginal vault prolapse can result in the distension of the vaginal apex outside of the vagina. An enterocele is a vaginal hernia in which the peritoneal sac containing a portion of the small bowel extends into the rectovaginal space. Vaginal vault prolapse and enterocele represent challenging forms of pelvic disorders for surgeons. These procedures often involve lengthy surgical procedure times.
Tension of an implant is typically adjusted during an implantation procedure sufficiently to take up any slack in the sling and impart at least a degree of increased and efficacious tension or desired positioning of supported tissue. Typically, implants such as urethral tapes or slings are fabricated of a loose weave sling fabric or mesh that engages tissue and encourages tissue ingrowth along the pathway through mesh pores to achieve chronic stabilization or “self-fixation.” Tissue ingrowth can take about 2-3 weeks in a typical patient in the absence of any significant intentional or unintentional movement of the mesh. During this post-operative time, the patient monitors the degree of success achieved in ameliorating symptoms of incontinence (e.g., urinary leakage) and any discomfort that might occur if the applied tension is so high as to unduly slow voluntary urination (for treating urinary incontinence). If any such problems occur it may be necessary to reopen the original surgical incisions to access and pull on the implant ends to tighten the central portion around the urethra (or other tissue being supported) or to on the implant central support portion to loosen the central support portion around the urethra. Several approaches have been taken to simplify or reduce the need for such post-operative adjustments.
Although effective in alleviating incontinence (e.g., anal, SUI), improvements in urethral and anal slings and other pelvic floor implants to post-operatively adjust tension applied to the urethra, anus, or other pelvic floor tissue, are desirable. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to the topical ophthalmic use of brimonidine in combination with timolol when indicated for treatment of glaucoma or ocular hypertension. Such combinations or formulations are available for separate use in the ophthalmic art and have been combined in serial application during the course of treatment of glaucoma. However, there are concerns and expressed reservations in the ophthalmic community about patient compliance when the patient is required to administer separate medications to treat a single disease or condition such as glaucoma. There is, moreover, a long felt need for an effective and safe topical ophthalmic pharmaceutical composition including brimonidine and timolol which has increased stability and requires a lower effective concentration of preservative as compared to the individual agents taken alone. Finally, there is a need to increase the efficacy of many topical ophthalmic agents, without increasing the systemic concentration of such topical agents, since it is well known that many of such topically-applied ophthalmic agents cause systemic side effects, e.g. drowsiness, heart effects, etc. Unexpectedly it has been discovered that brimonidine in combination with timolol meets these criteria.
Brimonidine is disclosed in U.S. Pat. No. 3,890,319. The use of brimonidine for providing neuroprotection to the eye is disclosed in U.S. Pat. Nos. 5,856,329; 6,194,415 and 6,248,741.
Timolol, as an ophthalmic drug, is disclosed in U.S. Pat. Nos. 4,195,085 and 4,861,760. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention is directed to bicycles and, more particularly, to a bicycle sprocket apparatus with reinforcement between sprockets.
Many bicycles have derailleur operated transmissions. Such transmissions usually include a plurality of front sprockets and a plurality of rear sprockets, wherein the plurality of front sprockets are mounted for rotation coaxially with the pedal cranks, and the plurality of rear sprockets are mounted for rotation coaxially with the rear wheel. A front derailleur is mounted to the bicycle frame in close proximity to the plurality of front sprockets to selectively engage a chain with one of the plurality of front sprockets, and a rear derailleur is mounted to the bicycle frame in close proximity to the plurality of rear sprockets to selectively engage the chain with one of the plurality of rear sprockets. A shift control device operated by the rider may manually or automatically control the front and rear derailleurs.
Adjacent pairs of the plurality of front or rear sprockets may be connected together by a sprocket support that comprises a plurality of radially extending mounting arms. Each mounting arm includes a sprocket mounting portion disposed between its corresponding pair of sprockets, and a fastener is used to fasten the pair of sprockets to the mounting portion. The number of mounting arms must be sufficient to firmly mount the sprockets to withstand the rotational force of the chain and to prevent lateral bending of the sprockets. On the other hand, it also is desirable to minimize the number of mounting arms to save weight. While a smaller number of mounting arms may sufficiently accommodate the rotational force of the chain, reducing the number of mounting arms also reduces lateral support between the sprockets, thus increasing the risk of lateral deflection of the sprockets caused by the chain. | {
"pile_set_name": "USPTO Backgrounds"
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Bar code symbols are presently widely used to label items for automated product identification. A bar code symbol consists of a sequence of light and dark regions referred to as elements or bars. These elements are typically rectangular in shape and often have a variety of possible widths. An arrangement of elements represents a character and is determined according to a set of rules and definitions typically referred to as a "code". A variety of codes such as the Universal Product Code (UPC) and Code 39 exist and provide a degree of uniformity.
More specifically, codes define a set of characters wherein each character is depicted and defined by a unique arrangement of elements. To encode a desired message having a number of characters, a collection of element arrangements are concatenated to form a bar code symbol, with each character of the message being represented by its own corresponding group of elements.
Characters recognized and defined by a code are referred to as legitimate characters while characters not recognized and defined by a code are referred to as illegitimate characters. Thus, an arrangement of elements not decodable by a given code corresponds to an illegitimate character(s) for that code.
In decoding the bar code symbol to extract a legitimate character message, a bar code reading device first scans the symbol and generates an electrical analog scan signal representative of the symbol. Next, the reading device and associated components attempt to decode the message from this analog scan signal according to the protocol of the code in use. A legitimate character message consists of one or more characters, each of which must be legitimate.
In particular, to generate the analog scan signal representative of the bar code symbol, the reading device scans the bar code symbol with a light source. A wide variety of light sources as well as sweeping devices arid methods may be employed. Illustratively, a laser is employed to sweep a laser beam across the symbol. As the laser beam scans the symbol, an optical sensor receives the light reflected by the elements of the symbol and generates the analog scan signal which is a function of the intensity of the reflection. A converter monitors and/or modifies this analog scan signal, detecting changes in the intensity of the reflected light as the laser crosses the boundary between two adjacent elements. By measuring and storing the amount of time between each such change in intensity, the converter creates a representation, referred to as a raw converted image, of the bar code symbol. Advantageously, the output of the converter is in a form suitable for decoding by a decoder. Illustratively, the amount of time between changes in intensity is measured in counts.
The converter may be a digitizer which creates a digital representation, referred to as a raw digital image, of the bar code symbol.
The decoder then compares this raw digital image against legitimate character image(s) as defined by the pertinent code. Unfortunately, any of a variety of sources of error, defects, and the like, singly and collectively referred to as distortion, may corrupt the above described scanning process and produce distorted analog scan signals and/or distorted digital images such that the raw digital image does not completely and accurately represent the bar code symbol being read. The decoder, unable to match the raw digital image with legitimate character image(s), will then indicate a decode failure. Preferably, the decoder performs this comparison on a character by character basis.
Specifically, a decode failure exists when the decoder is unable to decipher the output of the converter, i.e., when the decoder is unable to match the output of the converter with character images which are included in the specific code in use. Such character images which are included in and recognized by the specific code in use are referred to :s legitimate or valid characters. Thus, if a decode failure occurs, the character which was attempted to be decoded was an invalid character and the bar code symbol cannot be properly read.
Upon registering a decode failure, conventional bar code readers discard the entire distorted raw digital image and repeat the entire process described above until a scan is produced which is sufficiently free from distortion such that the decoder can match legitimate character image(s) with the raw digital image. Such legitimate character images are typically stored in or accessible to the decoder. However, this method is unnecessarily time consuming, particularly in circumstances where it is difficult to obtain a scan which is not distorted.
Difficulties associated with the inability to read a bar code symbol or the erroneous reading of a bar code symbol are especially common in applications involving relatively long bar code messages, i.e., bar code symbols having numerous elements. As the length of the message increases, the number of elements and characters increases, thereby raising the likelihood that distortion will be introduced at some point during the scan. Accordingly, the bar code reader may scan the symbol numerous times before producing a raw digital image sufficiently free from distortion that it can be decoded.
Further, bar code symbols may contain printing defects which are arranged such that it is unlikely to obtain a single distortion free scan, i.e., valid characters cannot be produced and the bar code cannot be read. Additionally, the bar codes may be printed in a dot matrix style in which case the ability to read the bar codes depends on the resolution of the print. Using conventional methods of decoding, such bar code symbols are often unreadable since readings thereof do not result in valid characters. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a novel chemical-sensitization photoresist composition or, more particularly, to a chemical-sensitization photoresist composition capable of giving a patterned resist layer with high contrast, high pattern resolution and high photosensitivity as well as an excellent cross sectional profile of the patterned resist layer and also having an advantage in respect of the stability of the latent image before development after pattern-wise exposure to actinic rays.
In the photolithographic patterning technology for the manufacture of various kinds of semiconductor devices, liquid crystal display panels and the like by utilizing a photoresist composition, it is a remarkable trend in recent years that so-called chemical-sensitization photoresist compositions are acquiring more and more prevalence among various types of photoresist compositions. The chemical-sensitization photoresist composition here implied is a photoresist composition containing an chemical agent capable of releasing an acid by the irradiation with actinic rays while the thus generated acid has a catalytic activity on the radiation-induced changes in the solubility of the resinous ingredient in an aqueous alkaline developer solution so that the photoresist composition has a high photosensitivity with a relatively small exposure dose.
Chemical-sensitization photoresist compositions can be classified into two types including the positive-working photoresist compositions and negative-working photoresist compositions depending on the solubility change of the resist layer in an alkaline developer solution caused by the irradiation with actinic rays. The basic ingredients of a chemical-sensitization photoresist composition include the above mentioned radiation-sensitive acid-generating agent and a film-forming resinous ingredient which causes a change of the solubility in an aqueous alkaline developer solution by interacting with the acid released from the acid-generating agent by the pattern-wise exposure of the resist layer to actinic rays.
The formulations of the chemical-sensitization positive- and negative-working photoresist compositions are different in the film-forming resinous ingredients. Namely, the chemical-sensitization positive-working photoresist composition usually contains, as the film-forming resinous ingredient, a polyhydroxystyrene resin of which a part of the hydroxyl groups are substituted for the hydroxyl hydrogen atoms by solubility-reducing protective groups such as tert-butoxycarbonyl groups, tetrahydropyranyl groups and the like while the film-forming resinous ingredient in the chemical-sensitization negative-working photoresist composition is usually a combination of a polyhydroxystyrene resin, which is optionally substituted for a part of the hydroxyl hydrogen atoms by the solubility-reducing protective groups mentioned above, or a novolak resin with an acid-crosslinkable agent such as melamine resins, urea resins and the like.
Various attempts and proposals have been made heretofore for selection of the radiation-sensitive acid-generating agent used in the above described chemical-sensitization photoresist compositions including, for example, certain diazomethane compounds disclosed in Japanese Patent Kokai 3-103854, 4-210960 and 4-217249.
It is also known in the prior art to use an acid-generating agent which is a compound having an acid-dissociable group in the molecule as disclosed in Japanese Patent Kokai 64-26550 and 64-35433. The acid-generating compounds disclosed there, however, are limited to onium salt compounds. A chemical-sensitization photoresist composition formulated with such an onium salt compound as the acid-generating agent has a disadvantage that the performance thereof is subject to the adverse influences of standing waves of the exposure light so that the patterned resist layer formed therefrom sometimes has wavy side lines of the cross sectional profile. The above mentioned Japanese Patent Kokai 3-103854, 4-210960 and 4-217249 also teach use of a certain diazomethane compound as the acid-generating agent and, among these diazomethane compounds, the non-aromatic diazomethane compounds, such as bis(cyclohexylsulfonyl) diazomethane, in particular, are highly transparent to excimer laser beams of 248 nm wavelength and capable of giving a high pattern resolution though with disadvantages in respect of the relatively low efficiency for the generation of an acid as well as a low patterning contrast since the acid generated therefrom is a weak acid so that the photoresist composition formulated therewith can hardly exhibit a high photosensitivity. In addition, the resist layer obtained from a resist composition formulated with such a diazomethane compound as the acid-generating agent is disadvantageous in respect of the relatively low stability of the latent image, which is formed by the pattern-wise exposure to light, before the post-exposure baking treatment. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to a battery receptacle, more particularly to a battery receptacle that is short circuit proof.
2. Description of the Related Art
FIG. 1 illustrates a conventional battery receptacle 1 that includes an insulative casing 2, a positive electrode 25, a negative electrode 26, and an interface assembly 3.
The casing 2 includes top and bottom walls 21, 22 that define an accommodating space 20 therebetween for accommodating battery cells 100.
With further reference to FIG. 2, the positive electrode 25 has a first end portion 251 that extends into the accommodating space 20 in the casing 2 and that is in electrical contact with a positive terminal of one of the battery cells 100, and a second end portion 252 that is disposed externally of the accommodating space 20 and that abuts against the top wall 21 of the casing 2. The negative electrode 26 has a first end portion 261 that extends into the accommodating space 20 in the casing 2 and that is connected electrically to a negative terminal of one of the battery cells 100, and a second end portion 262 that is disposed externally of the accommodating space 20 and that abuts against the top wall 21 of the casing 2.
The top wall 21 of the casing 2 is formed with first and second grooves 210, 210′. The second end portion 252 of the positive electrode 25 is disposed in the second groove 210′ in the top wall 21 of the casing 2, whereas the second end portion 262 of the negative electrode 26 is disposed in the first groove 210 in the top wall 21 of the casing 2.
The interface assembly 3 includes an insulative body 30, and anode and cathode terminals 31, 32. The insulative body 30 has top and bottom surfaces, and a peripheral surface that interconnects the top and bottom surfaces of the insulative body 30. The anode terminal 31 is disposed at a center of the insulative body 30, and has a first end portion 311 that projects from the top surface of the insulative body 30, and a second end portion 312 that projects from the bottom surface of the insulative body 30. The cathode terminal 32 is provided on the peripheral surface of the insulative body 30.
When the interface assembly 3 is disposed on the top wall 21 of the casing 2, the second end portion 312 of the anode terminal 31 is in electrical contact with the second end portion 252 of the positive electrode 25, and the cathode terminal 32 is in electrical contact with the second end portion 262 of the negative electrode 26.
With further reference to FIG. 3, the battery receptacle 1 further includes five electrical contacts 24 for connecting the battery cells 100 in series. Three of the electrical contacts 24 are provided on the bottom wall 22 of the casing 2, whereas two of the electrical contacts 24 are provided on the top wall 21 of the casing 2. The battery receptacle 1 is provided with a plurality of grooves 240, two of which are formed in the top wall 21 of the casing 2 and three of which are formed in the bottom wall 22 of the casing 2. Each of the grooves 240 is defined by a groove-defining wall 241. Each of the electrical contacts 24 has a portion that is disposed in a respective one of the grooves 240 and that engages a respective one of the groove-defining walls 241.
The aforementioned conventional battery receptacle 1 is disadvantageous in that, when it is subjected to shock during use, the cathode terminal 32 may intermittently lose its electrical contact with the second end portion 262 of the negative electrode 26. Moreover, in severe instances, the shock may cause a short circuit between the cathode terminal 32 and the second end portion 252 of the positive electrode 25. Further, the insertion of the electrical contacts 24 in the grooves 240 during assembly requires much effort. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field
Embodiments relate to a material layer, a semiconductor device including the material layer, and methods of fabricating the material layer and the semiconductor device.
2. Description of the Related Art
A material used to obtain a minute pattern may be sensitive to high temperatures, and a low-temperature process may be desirable. | {
"pile_set_name": "USPTO Backgrounds"
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Protein conjugation lies at the heart of the discovery and development of protein therapeutics. Chemical modification strategies typically employ a two step process where the first step involves site-specific modification of the protein and the second step is the installation of an entity of interest. The selectivity of the second step is often a consequence of the chemospecific reactivity of a donor-acceptor pair, e.g., aminooxy donor-carbonyl acceptor, whose reactivity is orthogonal to that of peptide side-chains. (Tam et al., Biopolymers. 51:311-32, 1999)
The first step involving modification of the protein can be difficult to effect site-specifically by chemical methods in view of the presence of many peptide residues of the same type. Accordingly, limited success has been achieved in such site-specific modifications, although enzymes have been used to effect these transformations. For example, it has been demonstrated that group modification agents with minimal binding determinants can sometimes react site-specifically due to enzyme active sites, e.g., active site serines of proteinases (Means et al., Chemical Modification of Proteins, Holden-Day, Inc., San Francisco, 1971.)
For proteins that have not evolved to do such chemistry, the challenges for site-specific labeling are far greater than for the construction of active-site directed reagents. For such proteins the challenges can be likened to the development of site-specific modifications of non-active site residues of enzymes. Thus, other than for active-sites, and allosteric sites that have evolved to bind enzyme modulators, site-specific labeling reagents (affinity labels) are lacking and novel approaches are required to fill that void. Amino acid residues usually have little to distinguish their reactivity from others in the same class, with the exception of cysteine thiols whose chemistry is quite distinct from other peptidic side chain functionality. Alternatively, strategies for the installation of functional groups that can engage in orthogonal conjugative reactions can be useful for the selective modification of proteins.
For these reasons, methods for the site-specific modification and ligation of proteins would be useful for the synthesis of modified peptide, polypeptide, and protein adducts and use of the adducts in radio-labeling, molecular imaging and protein therapeutic applications, and in methods of medical treatment. | {
"pile_set_name": "USPTO Backgrounds"
} |
Retail shrinkage is becoming a huge problem for retail merchants (e.g., stores). Retail shrinkage can be attributed to factors such as employee theft, shoplifting, fraudulent or unintentional administrative error, vendor fraud, damage in transit or in store, fraudulent or unintentional transactions at the point of sale (POS) (e.g. by the cashier) etc. According to retailers, most incidents of employee theft occur at point of sale (POS) where store staff use fraudulent means to bypass the barcode registration of retail goods. For instance, POS personnel at a POS site in a store may permit an individual (e.g., a friend or family member of the POS personnel) to move through the POS site with retail goods from the store without paying for the goods or after paying a reduced amount for the goods. This causes retail loss for organizations, and further hampers growth of the organization.
Shrinkage loss prevention measures involves some robust processes to detect fraud or theft, often backed by enforcement and recovery. These include video surveillance at POS, installation of theft deterrent devices, EAS alarms at entrances etc. These measures are generally implemented to identify fraudulent transactions by capturing and recording behavior deviations with video systems for subsequent analysis. But, any sort of human review and analysis of video data is time consuming and inefficient when the scale of data becomes large which is inevitable in today's scenario.
Accordingly, detecting and preventing this retail shrinkage may be desirable for retail merchants. Existing techniques to address the problem of retail shrinkage caused by employee theft at a POS uses techniques such as voting mechanism to classify a pattern into either a fraudulent transaction or a genuine one. The voting mechanism involves frequency-based, SVM-based (Support Vector Machines) or a combination of SUV and frequency based techniques. These techniques along with pattern classification techniques are used to classify any new pattern into fraud and genuine classes. However, the voting mechanism based on frequency has been observed to be inaccurate as it causes false alarms, which leads to unnecessary chaos. Further, it has been observed that with existing methods involving use of pattern recognition techniques, incidence of false alarms and inaccurate detection or lack of detection of fraudulent transactions is widespread.
In light of the above drawbacks, there is a need for a system and a method which accurately detects fraudulent transactions at a transaction site. There is also a need for a system and a method which maximizes true detection of any fraud transaction and minimizes any sort of false alarms. Further, there is a need for a system and a method which is capable of analyzing pattern of events associated with one or more transactions in real time using surveillance data and transaction log data and detect fraudulent transactions. Yet further, there is a need for a system and a method which can be easily implemented at a Point of Sale (POS) with concentration on retail shrinkage primarily due to theft of inventory by employees. | {
"pile_set_name": "USPTO Backgrounds"
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Pneumatic conveying systems of the kind having several inlet points for conveyed material normally include valves controlling the discharge of material from each of the inlets and into a transport pipe net. Valves having such a function will in this specification be referred to as “discharge valves”. Such pneumatic conveying systems involve a few typical situations when the behavior of the discharge valves needs to be individually configured with respect to operation time. This individual valve configuration normally includes setting a time/delay before opening a first discharge valve of a branch after activating the branch by generating air flow therein. The individual time/delay configuration of the discharge valves of the material inlets serves to ensure appropriate transport airspeed in the branch. In the case of a system involving several branches the set time/delay for the first discharge valve of each branch starts after switching active branch by opening the appropriate air inlet valve. The individual valve configuration may further include setting a proper time/delay between consecutive openings of discharge valves in order to avoid overloading the system.
Presently, both of the above mentioned operation times/delays are normally individually configured for each branch of a multiple branch system and thus for each valve depending on its localization along the transport pipe net and also depending on its typical material production ratio. Optimization of a system configuration with respect to efficiency—may in this field be specified as energy per amount of transported material—involves finding as low time/delay values as possible without interfering with safe material transport. Any static or predefined configuration must have built-in compensation for “worst-case” situations and variations and will have sub-optimal efficiency under average working conditions.
WO 2011/108971 A1 discloses sensors provided in direct association with a storage space of a pneumatic material collection and transport system. The sensors are of a type suitable for detecting waste remaining in a storage space. They are used to detect when a storage space has been adequately emptied so that its discharge valve may be closed and an emptying cycle of a next storage space in a system emptying sequence may be initiated with minimum delay. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a stencil printer capable of printing an image on a paper or similar recording medium with a master wrapped around its ink drum. More particularly, the present invention relates to a stencil printer including a power save mode for saving power when it is not used.
A digital stencil printer is conventional which uses a laminate thermosensitive stencil made up of a thermoplastic resin film and a porous support adhered to each other. The printer includes a thermal head for selectively perforating, or cutting, the resin film of the stencil with heat in accordance image data. After the perforated stencil or master has been wrapped around an ink drum, ink feeding means arranged in the drum feeds an adequate amount of ink to the inner periphery of the drum. A press roller, press drum or similar pressing member presses a paper or similar recording medium against the ink drum so as to transfer the ink from the drum to the paper via the porous portion of the drum and the perforations of the master. As a result, an image represented by the image data is printed on the paper. A modern stencil printer is capable of performing a continuous sequence including master making, used master discharging, paper feeding and printing steps. This, coupled with the increasing resolution and reducing performance cost, has recently motivated users of the kind producing, say, ten or more copies at a time to use the stencil printer in place of a copier.
Now, it is not unusual that a stencil printer or a copier is simply left unused over a long period of time with its power switch turned on, meaning that the actual operation time thereof is short. Even when the printer or the copier is unused, power is wastefully fed to its various drivelines, sensors, and a control panel. To solve this problem, the power switch may be turned off while the printer or the copier is not used. However, a heater for fixing a toner image is essential with the copier. Should power supply to the heater be turned off, it would take several minutes for the heater to be again warmed up to its operative temperature, delaying the first print time.
In light of the above, Japanese Patent Publication No. 5-31141, for example, discloses a copier having a power save mode for saving power when it is not used.
On the other hand, it is a common practice with a stencil printer, which does not need the above heater, to turn off its power switch when the printer is unused. This, however, brings about the following problem to be solved. In a stencil printer capable of continuously performing master making, used master discharging, paper feeding and printing steps, sections for executing such steps include a plurality of sensors for monitoring, e.g., the size of documents and that of papers, the position of the leading edge of a master, the position of an ink drum, and the position of a compresser for compressing a used master removed from the ink drum. It follows that every time the power switch is turned on, various members including the ink drum and compressor must be returned to their home positions all over again, delaying the first print time by about several ten seconds.
A section included in the stencil printer for feeding papers has traditionally been implemented by a fixed size system or a cassette system. Likewise, a section for discharging the paper or printing has conventionally included side fences which are moved by hand in matching relation to a paper size. Japanese Patent Laid-Open Publication No. 5-124737, for example, proposes a paper feeding system capable of sensing the size and the remaining amount of papers and automatically replenishing and feeding the papers. Also, Japanese Patent Laid-Open Publication No. 10-1254, for example, teaches a paper discharging section capable of automatically moving the side fences in matching relation to a paper size. These automatic paper feed and paper discharge schemes, however, aggravate power consumption when the stencil printer is not used.
Further, a personal computer, sorter or similar peripheral unit is often connected to the stencil printer for causing the printer to operate by sending image data via the peripheral unit. In this condition, maintaining the power switch of the printer turned off is not practical, and a configuration for saving power in the stand-by state of the printer is desired.
Technologies relating to the present invention are also disclosed in, e.g., Japanese Patent Laid-Open Publication Nos. 6-293175, 7-143746, 7-186492, and 8-251317.
It is therefore an object of the present invention to provide a stencil printer having a power save mode for saving power when it is in a stand-by state, and preventing the first printing time from being delayed when it recovers from the power save mode.
In accordance with the present invention, a stencil printer for printing an image on a recording medium with a master wrapped around its ink drum and having a power save mode for saving power when it is not used includes a storing section for storing the conditions of the printer when the power save mode is selected. When the power save mode is selected, a comparing section compares the conditions stored in the storing section and the current conditions of the printer.
Also, in accordance with the present invention, a printing method for causing a stencil printer to print an image on a recording medium with a master wrapped around an ink drum, and including a power save mode for saving power when the printer is not used includes the steps of storing the conditions of the printer when the power save mode is selected, and comparing, when the power save mode is cancelled, the conditions stored and the current conditions of the printer. | {
"pile_set_name": "USPTO Backgrounds"
} |
Field of the Invention
The present invention relates generally to electric motors and, more particularly, to a reduced weight rotor for use in such motors.
Description of the Prior Art
Electric motors have been in existence for over one hundred years now. Despite this, today there is a renewed interest in them due to an ever-increasing concern about the environmental impact of other forms of power generation such as gasoline engines.
One known form of electric motors is commonly referred to as a brushless permanent magnet motor due to its design and operation. Referring now to FIG. 1, a simplified diagram of just such an electric motor can be seen. As shown in the figure, motor 100 comprises a stationary part referred to as a stator 102 and a rotating part referred to as a rotor 104. In this example, stator 102 includes three separate phase wire windings, labeled phase A wire winding 106, phase B wire winding 108, and phase C wire winding 110 in the figure, each of which includes wire wound around an armature, known as a tooth, of stator 102. As is known in the art, the space along the stator between two neighboring teeth is commonly referred to as a slot. As also shown in this example, rotor 104 includes two permanent magnet poles labeled magnet N 112 (for North) and magnet S 114 (for South), about its periphery. This stator and rotor electric motor configuration is known as an “inrunner” because the rotor is located inside the stator (versus an “outrunner” where the physical relationship between the stator and rotor is reversed) and, in either configuration, the physical space or gap between the teeth of stator 102 and the permanent magnets of rotor 104 is commonly referred to as an air gap.
In operation, a motor controller (not shown) provides electric current across the three winding phases (e.g., phase A wire winding 106, phase B wire winding 108, and phase C wire winding 110) in a sequential fashion around stator 102 thus making it a three-phase motor. As current is running through a given wire winding it generates a local magnetic field which then repels and/or attracts any nearby permanent magnets such as permanent magnet N 112 and permanent magnet S 114 of rotor 104 thereby causing rotor 104 to spin or rotate about its axis. In this way, electric motor 100 can be applied to a variety of uses by, for example, having a drive gear (not shown) located on a spinning shaft 116 at the axis of rotor 104.
In further explanation and by way of example, the motor controller (not shown) applies a positive voltage to one end of the phase A wire winding 106 and a negative voltage to one end of the phase B wire winding 108. This voltage differential creates an electric current from the one end of the phase A wire winding 106 to a “Wye” termination and then to the one end of the phase B wire winding 108 because, as shown in the figure, the other ends of the phase A wire winding 106 and the phase B wire winding 108 (as well as that of one of the ends of the phase C wire winding 110) are electrically connected in the form of a “Wye” termination, a form of termination connection known in the art. This electric current, as explained above, creates a magnetic field surrounding the wire windings, such as phase A wire winding 106 and phase B wire winding 108. These magnetic fields repel (and/or attract, as the case may be) respective ones of magnet N 112 and/or magnet S 114 thereby causing rotor 104 to spin about it axis. The motor controller then applies a voltage differential across one end of the phase B wire winding 108 and one end of the phase C wire winding 110 causing rotor 104 to continue to spin. The motor controller then applies a voltage differential across one end of the phase C wire winding 110 and one end of the phase A wire winding 106 causing rotor 104 to further continue to spin. This process is repeated thus continuing to cause rotor 104 to spin or rotate within stator 102.
It is to be understood that the diagram of motor 100 of FIG. 1 is a simplified form of such an electric motor. As is known in the art, increasing the size and number of the active motive elements, such as the size of the stator and the number of windings (as well as the number of wire windings on each tooth) on the stator and the size of the rotor and the number (and power) of magnets on the rotor, increases the motive force or power of the electric motor. Therefore, in practice, it is common for each of the phase wire windings to be duplicated (so that there is more than one phase A wire winding 106, more than one phase B wire winding 108, and more than one phase C wire winding 110) at additional teeth locations around a stator thereby providing additional magnetic fields to repel (and/or attract) any magnets on a rotor. Likewise, it is common for each of the magnets of a rotor to be duplicated (so that there is more than one N magnet 112 and more than one S magnet 114) thereby providing additional magnets to be repelled (and/or attracted) by a stator's wire windings.
Referring now to FIG. 2, an exploded diagram of an electric motor 200 of the prior art can be seen. As shown, electric motor 200 includes a drive end plate 202, a motor casing 204 having radial heat fins for passive air cooling, a stator 206 comprising a set of stacked laminations and wire windings (not shown), a rotor 208 comprising permanent magnets located about its periphery, and a rear end plate 210.
It is to be understood that the basic physical relationship and operation of these elements in motor 200 is generally as was described with respect to that of motor 100 of FIG. 1. In particular, rotor 208 fits within stator 206, separated by an air gap, both of which then fit within motor casing 204 with drive end plate 202 attached to and closing a front end of motor casing 204 while rear end plate 210 is attached to and closes a rear end of motor casing 204. As has been explained, rotor 208 is then caused to rotate within stator 206, by the application of a voltage differential across the wire windings on stator 206 which repel and/or attract the magnets of rotor 208.
Of course, a given motor may be limited in how physically large it can be for a given use case thus limiting the extent of any increases in active motive material (e.g., the size of the stator, the number of wire windings and/or number of wire windings per tooth, the size of the rotor, and the number and power of the magnets). Further, within any overall size constraints for a given motor, it may be desirable to reduce the motor's weight in order to improve its performance characteristics and/or overall usefulness for a given application. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to state machines, and in particular, to pattern matching applications that represent the patterns to be matched as one or more state machines.
2. Description of the Related Technology
In modern applications it is typical to have patterns that number in the thousands to as many as a million or more. For example, network security applications use large numbers of patterns to detect malicious content such as viruses, spam, and attempts to interfere with proper functioning of the network by gaining unauthorized access to resources and/or hampering performance. Recent advances in technology have made it feasible to do more than packet header inspection by using high-speed hardware that can look at all the bytes in a packet using a programmable state machine engine. Such a packet inspection engine may execute instructions that are, for example, created by a compiler that converts regular expressions into a deterministic finite automata (DFA), which is represented by the instructions.
Because high speed may be important, executable state machine instructions are stored in a manner that is conducive to fast access. This is generally at the expense of consuming more space. For example, 4,000 regular expressions that detect network intrusion can require 200 MB or more of storage when compiled for efficient execution. However, this is in opposition to the requirements of lower cost consumer products which may only have, for example, 50 MB or less available. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention.
The present invention relates to electronic amplifier circuits. In particular, the present invention is an audio power amplifier which can be directly coupled to a load.
2. Description of the Prior Art.
Power amplifiers are well known and disclosed, for example, in U.S. Pat. Nos. 3,191,126 granted to Fowler in June 1965, 3,042,875 granted to Higginbothan in July 1962, and 4,229,706 granted to Bongiorno in October 1980. Desirable characteristics of audio power amplifiers include a high damping factor, wide frequency response, high transient response, and low overall distortion. The tradeoff in achieving these characteristics is, of course, overall cost of the amplifier.
While the vast majority of audio power amplifiers on the market today are transistorized, extremely high performance audio power amplifiers often use vacuum tubes as output devices. Vacuum tube power amplifiers, however, typically require a matching transformer to match the high impedance of the tube circuits to the low impedance of the loudspeaker load. The matching transformer also prevents the high voltages found in conventional tube circuits from damaging the loudspeaker.
One vacuum electron tube audio power amplifier which does not use a matching transformer at its output is known as the Futterman Amp. This particular amplifier design uses a well known "totem pole" output like many solid-state designs, and shares some of the same weaknesses. Some versions of this amplifier also include coupling capacitors to block harmful DC voltages. The output coupling capacitors, however, adversely affect the slewing response of the amplifier, and also introduce non-linearities into its phase response. As a result, the output coupling capacitors have many of the same limitations as the matching transformers.
Totem pole amplifiers, which comprise the majority of solid-state designs, as well as direct-coupled tube designs, have inferior distortion caracteristics. These distortion characteristics, when coupled to the odd-ordered harmonic distortions of solid-state devices, make totem pole amplifier configurations less than desirable.
It is evident that there is a continuing need for improved audio power amplifiers. An audio power amplifier design which permits the use of vacuum tube output devices which can be directly coupled to a loudspeaker load would be especially desirable. This amplifier must be capable of producing high output power levels over a wide bandwidth with low distortion. Of course, the design must be simple, to allow easy implementation. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to a semiconductor device, a liquid crystal display device, a process for a semiconductor device and a process for a liquid crystal display device, in particular to a semiconductor device, a liquid crystal display device, a process for a semiconductor device and a process for a liquid crystal display device which include field effect transistors having an LDD (Lightly Doped Drain) structure.
2. Description of the Background Art
Conventionally, a liquid crystal display device, which utilizes thin film field effect transistors formed on a glass substrate, has been known as one of liquid crystal display devices. A glass substrate where thin film field effect transistors are formed in such a liquid crystal display device is shown in FIG. 47. FIG. 47 is a cross section diagram showing a conventional liquid crystal display device. Referring to FIG. 47, a liquid crystal display device is described.
Referring to FIG. 47, an n type thin film field effect transistor 119 and a p type thin film field effect transistor 120 are formed in a drive circuit region on a glass substrate 101 in a liquid crystal display device. In addition, a capacitor 121 and a thin film field effect transistors 122 for a pixel are formed in a display pixel region.
In the drive circuit region, a base film 102 is formed on the glass substrate 101. A silicon oxide film is used for this base film n+ type impurity regions 103a, 103b, nxe2x88x92 type impurity regions 104a, 104b and a channel region 106a are formed on the base film 102 by using the same semiconductor film. A gate insulating film 107a is formed on the channel region 106a. A gate electrode 108a is formed on the gate insulating film 107a. The source/drain regions are formed of n+ type impurity regions 103a, 103b and nxe2x88x92 type impurity regions 104a, 104b. The n type thin film field effect transistor 119 is formed of those n+ type impurity regions 103a, 103b, nxe2x88x92 type impurity regions 104a, 104b, channel region 106a, gate insulating film 107a and gate electrode 108a.
In addition, p type impurity regions 105a, 105b and a channel region 106b are formed on the base film 102 by using the same semiconductor film. A gate insulating film 107b is formed on the channel region 106b. A gate electrode 108b is formed on the gate insulating film 107b. A p type thin film field effect transistor 120 is formed of those p type impurity regions 105a, 105b, channel region 106b, gate insulating film 107b and gate electrode 108b. An interlayer insulating film 110 is formed on those n type thin film field effect transistor 119 and p type thin film field effect transistor 120. In the regions located above the n+ type impurity regions 103a, 103b and the p type impurity regions 105a, 105b, contact holes 111a to 111d are formed in the interlayer insulating film 110. Metal wires 112a to 112d are formed so as to extend from the inside of the contact holes 111a to 111d to the upper surface of the interlayer insulating film 110. A passivation film (not shown) is formed on the metal wires 112a to 112d. A flatting film 113 is formed on the passivation film.
In the display pixel region, a capacitor electrode 109 is formed on the base film 102. Another capacitor electrode 108e is formed above the capacitor electrode 109 via an insulating film 107e as the dielectric film. A capacitor 121 is formed of these capacitor electrodes 109, 108e and insulating film 107e. An n+ type impurity region 103c is formed, as the conductive region, on the base film 102 so as to adjoin the capacitor electrode 109. In addition, n+ type impurity regions 103d to 103f, nxe2x88x92 type impurity regions 104d to 104g and channel regions 106c, 106d are formed on the base film 102 by using the same semiconductor film. Gate insulating films 107c, 107d are formed on the channel regions 106c, 106d, respectively. Gate electrodes 108c and 108d are formed on the gate insulating films 107c, 107d, respectively. In this way, one thin film field effect transistor is formed of the n+ type impurity regions 103d, 103e, the nxe2x88x92 type impurity regions 104d, 104e, the channel region 106c, the gate insulating film 107c and the gate electrode 108c. In addition, another thin film field effect transistor is formed of the n+ type impurity regions 103e, 103f, the nxe2x88x92 type impurity regions 104f, 104g, the channel region 106d, the gate insulating film 107d and the gate electrode 108d. The thin film field effect transistors 122 for pixels include those two thin film field effect transistors.
An interlayer insulating film 110 is formed on the capacitor 121 and the thin film field effect transistors 122 for a pixel. In the regions located above the n+ type impurity regions 103c, 103d and 103f, contact holes 111e to 111g are formed in the interlayer insulating film 110. Metal wires 112e and 112f are formed so as to extend from the inside of the contact holes 111e to 111g to the upper surface of the interlayer insulating film 110. A passivation film (not shown) is formed on the metal wires 112e and 112f. A flatting film 113 is formed on the passivation film. In the region located above the metal wire 112e, a contact hole 114 is formed in the flatting film 113 and the passivation film. A pixel electrode 115 is formed so as to extend from the inside of the contact hole 114 to the upper surface of the flatting film 113 by using ITO or the like.
FIGS. 48 to 51 are cross section diagrams for describing a process for the liquid crystal display device as shown in FIG. 47. Referring to FIGS. 48 to 51, a process for a liquid crystal display device is described.
First, a base film 102 such as a silicon oxide film is formed on a glass substrate 101. An amorphous silicon film is formed on this base film 102. A polysilicon film is formed by annealing this amorphous silicon film using a laser or the like. A resist film is formed on this polysilicon film. A channel pattern is formed by carrying out an exposure to light and development processing on this resist film. Then, by using, as a mask, the resist film where the channel pattern is formed, the polysilicon film is etched so as to form polysilicon films 127a to 127c (see FIG. 48) and polysilicon film to be a capacitor electrode. After that, the resist film is removed. By implanting conductive impurities into the polysilicon film to be the capacitor electrode, a conductive film 128 (see FIG. 48) is formed. An insulating film to be a gate insulating film is formed on the polysilicon films 127a to 127c and the conductive film 128. A conductive film is formed on this insulating film. A resist film is formed on this conductive film. A gate pattern is formed in the resist film by carrying out exposure to light and development processing. By using, as a mask, the resist film where the gate pattern is formed, gate electrodes 108a to 108d (see FIG. 48) and a capacitor electrode 108e (see FIG. 48) are formed by carrying out wet etching. After that, the resist film is removed. Then, by using the gate electrodes 108a to 108d and the capacitor electrode 108e as a mask, the insulating film is etched so as to form the gate insulating film 107a to 107b (see FIG. 48) and the insulating film 107e (see FIG. 48) as the dielectric film. In this way, a structure as shown in FIG. 48 is gained.
After that, as shown in FIG. 49, a resist film 130b is formed so as to cover the region where the p type thin film field effect transistor 120 (see FIG. 47) is to be formed and at the same time resist film 130a, 130c and 130d is formed which becomes a mask for forming the n+ type impurity regions 103a to 103f. Then, phosphorus (P) ions 133 as impurity ions are implanted into predetermined regions in the polysilicon films 127a to 127c (see FIG. 48). In this manner, the n+ type impurity regions 103a to 103f are formed. After that, the resist films 130a to 130d are removed.
Next, as shown in FIG. 50, phosphorous ions 134 are implanted into predetermined regions under the condition where no resist film exists and, thereby, nxe2x88x92 type impurity regions 104a, 104b, 104d to 104g are formed.
Next, as shown in FIG. 51, resist films 135a to 135c are formed in the regions other than the regions where the p type thin film field effect transistor 120 (see FIG. 47) is to be formed. Then, boron (B) ions 136 are implanted by using the gate electrode 108b as a mask and, thereby, p type impurity regions 105a, 105b and channel region 106b are formed. After that, the resist films 135a to 135c are removed.
After this, an interlayer insulating film 110 (see FIG. 47) is formed. A resist pattern is formed on this interlayer insulating film 110. The interlayer insulating film 110 is partially etched and removed by using this resist pattern as a mask and, thereby, contact holes 111a to 111g (see FIG. 47) are formed. After that, the resist pattern is removed. Then, after carrying out a cleaning process, a metal layer which is processed to become metal wires 112a to 112f is formed so as to extend from the inside of the contact holes 111a to 111g to the upper surface of the interlayer insulating film 110. A resist pattern is formed on this metal layer. The metal film is partially removed by carrying out wet etching using this resist pattern as a mask. In this manner, the metal wires 112a to 112f (see FIG. 47) are formed. After that, the resist pattern is removed. A passivation film 113 (see FIG. 47) is formed on the metal wires 112a to 112f. After flatting the upper surface of the passivation film 113, a contact hole 114 (see FIG. 47) is formed in this passivation film 113. A transparent conductive film is formed so as to extend from the inside of the contact hole 114 to the upper surface of the passivation film 113. A resist film wherein a pixel pattern is formed on this transparent conductive film. By using this resist film as a mask the transparent conductive film is partially removed through wet etching so as to form a pixel electrode 115 (see FIG. 47). After that, the resist film is removed.
In this manner, a liquid crystal display device as shown in FIG. 47 can be gained.
In the conventional process for a liquid crystal display device as described above, the problem arises as follows. That is to say, in the step as shown in FIG. 49, the positions or the size of the nxe2x88x92 type impurity regions 104a, 104b (see FIG. 50) vary depending in the relative positioning relationship with the resist film 130a and the gate electrode 108a when noticing, for example, the region in which the n type thin film field effect transistor 119 (see FIG. 47) is to be formed. This point is described in more detail referring to FIGS. 52 and 53.
FIGS. 52 and 53 are diagrams for describing a conventional problem, which are partially enlarged cross section diagrams of the region wherein a resist film 130a is formed in the step as shown in FIG. 49.
Referring to FIG. 52, in the case that the relative positional relationship is shifted from the set position between the gate electrode 108a and the resist film 130a (the position of the resist film 130a is shifted either to the right or to the left), the respective sizes of the finally formed nxe2x88x92 type impurity regions 104a and 104b vary as shown in FIG. 52. In this manner, in the case that the sizes of the nxe2x88x92 type impurity regions 104a and 104b on the right and on the left are different, the electric property of the formed n type thin film field effect transistor 119 fluctuates from the designed value and, as a result, the problem arises in that the reliability of the liquid crystal display device is lowered.
In addition, as shown in FIG. 53, in the case that the distance W1 between the sidewall of the gate electrode 108a and the sidewall of the resist film 130a becomes small with respect to the necessary width W0 of the n type impurity regions 104a, 104b, the resultant width of the n type impurity regions 104a, 104b becomes smaller than the designed value. As a result of this, the electric property of the n type thin film field effect transistor becomes different form the designed value. As a result, in the same manner as the above described case, there are some cases where the reliability of the formed liquid crystal display device is lowered.
In addition, it is considered to introduce the step of carrying out an implantation of phosphorous ions 133 in order to form the n+ type impurity regions 103a, 103b under the condition where the insulating film 137 which is processed to be a gate insulating film is not removed but rather extends to the n+ type impurity regions 103a, 103b at the time of forming a thin film field effect transistor as shown in FIG. 54. Here, FIG. 54 is another diagram for describing the conventional problem. In the case that such a step is carried out, however, the same problem as the above described problem occurs. In addition, under the condition where the insulating film 137 remains as in the above, phosphorous ions 133 need to reach the regions in which n+ type impurity regions 103a, 103b are to be formed by passing through the insulating film 137 and, therefore, the implantation energy of phosphorous ions 133 needs to be made larger, which causes the case where the resist film 130a is changed in quality through this implantation of phosphorous ions. In some cases the resist film 130a, which has been changed in quality in this manner, partially remains without being removed in the removal step of this resist film 130a. In the case that the resist film 130a remains in this manner, defects are caused such that a predetermined structure cannot be formed because of the resist film 130a which has remained in place during the following process steps, which consequently lowers the reliability of the liquid crystal display device and which lowers the yield.
This invention is provided to solve such a problem and one purpose of this invention is to provide a semiconductor device which has a high reliability and a method for the same.
Another purpose of this invention is to provide a liquid crystal display device which has a high reliability and a method for the same.
A semiconductor device according to the one aspect of this invention includes a substrate, a semiconductor film, a gate insulating film and a gate electrode. The semiconductor film is formed on the main surface of the substrate and includes the source and drain regions adjoining each other via the channel region. The gate insulating film is formed on the channel region. The gate electrode is formed on the gate insulating film and has sidewall. The gate insulating film includes an extended part which has sidewall located outside of the sidewall of the gate electrode. One of the source and drain regions include a high concentration impurity region and a low concentration impurity region of which the impurity concentration is relatively lower than this high concentration impurity region. The high concentration impurity region is formed in a region of the semiconductor film apart from the sidewall of the extended part. The low concentration impurity region is formed in a region of the semiconductor film located below the extended part.
In addition, in the semiconductor device according to the first aspect of this invention, both of the source and drain regions preferably include a high concentration impurity region and a low concentration impurity region, respectively.
By having such a structure, the position of the low concentration impurity region can be determined by using the extended part as a mask as shown in the manufacturing method described below. Then, the size (width) of this extended part is determined by partially removing the sidewall of the gate electrode by using wet etching as shown in the manufacturing method described below. Then, since the positional precision of this wet etching is sufficiently higher than the positional precision in the photolithography, which has conventionally been used for forming a low concentration impurity region, the positional precision of the low concentration impurity region can be increased. Therefore, the positional precision of the low concentration impurity region of the formed field effect transistor can be increased. As the result of this, the reliability of the field effect transistor can be increased.
In addition, in the case that an interlayer insulating film or the like is formed so as to extend from the gate electrode to the semiconductor film including the source and drain regions, a void or the like is easily created in the connection parts (corner parts) between the sidewalls of the gate electrode and the gate insulating film and the upper surface of the semiconductor film. In particular, in the case that the sidewalls of the gate electrode and the gate insulating film are located in approximately the same plane and the gate electrode and the gate insulating film form one step part, the above tendency is significant. In the present invention, however, since the extended part of the gate insulating film has already been formed in such corner parts wherein a void is the most easily created according to a prior art, the possibility where a void is created as described above can be reduced.
In addition, since a void can be prevented from being created in the corner parts formed of the sidewalls of the gate electrode and the gate insulating film and the upper surface of the semiconductor film as described above, the problem that the interlayer insulating film or the like peals due to such a void can be prevented from occurring. As a result of this, damage or an operational defect of the semiconductor device caused by such pealing of interlayer insulating film can be prevented from occurring and, therefore, the reliability of the semiconductor device can be increased.
In a semiconductor device according to the above one aspect, it is preferable for the sidewall of the extended part to be formed so as to incline with respect to the main surface of the substrate.
In this case, as shown in the manufacturing method described below, a concentration distribution so as to correspond to the inclination of the sidewall of the extended part with respect to the impurity concentration in low concentration impurity region can be formed. As a result of this, an electric field concentration can be more efficiently prevented from occurring in the low concentration impurity region.
In addition, since the sidewall of the extended part is formed so as to be inclined, at the time when an interlayer insulating film or the like is formed so as to extend from the sidewall of the gate electrode to the upper surface of the semiconductor film, the coverage of this interlayer insulating film or the like can be more improved.
In the semiconductor film according to the above one aspect, it is preferable for the gate insulating film to include an insulating film part which extends from the sidewall of the extended part to the high concentration impurity region and it is preferable for the film thickness of the insulating film part is thinner than the film thickness of the extended part or the gate insulating film.
In this case, because of the existence of the insulating film part, this insulating film part works as a protective film and, therefore, the source and drain regions can be effectively prevented from being contaminated with impurity metal or the like. As the result of this, the change of the electric characteristics of the semiconductor device due to the contamination with the impurity metal or the like in the source and drain regions can be prevented without fail and, therefore, the reliability of the semiconductor device can be more improved.
A liquid crystal display device according to the another aspect of this invention is provided with a semiconductor device according to the above first aspect.
In this case, a semiconductor device which has a high reliability can be formed as a semiconductor device in the drive circuit region or in the display pixel region of a liquid crystal display device and, therefore, the uniformity of the screen display characteristics of the liquid crystal display device can be improved. As a result of this the display characteristics of the liquid crystal display device can be improved.
In a manufacturing method for a semiconductor device according to the still another aspect of this invention, a semiconductor film is formed on the substrate. An insulating film is formed on the semiconductor film. A conductive film is formed on the insulating film. A resist film which has a sidewall is formed on the conductive film. By partially removing the conductive film through etching using the resist film as a mask, a gate electrode which has a sidewall located inside of the sidewall of the resist film is formed. By partially removing the insulating film through etching using the resist film as a mask, a gate insulating film including an extended part which has a sidewall located outside the sidewall of the gate electrode is formed. By implanting impurities into the semiconductor film by using the resist film as a mask, a high concentration impurity region for one of the source and drain regions are formed in a region of the semiconductor film apart from the sidewall of the extended part. At this time, high concentration impurity regions may be formed respectively in the source and drain regions. Then the resist film is removed. After the step of removing the resist film, by implanting impurities to the semiconductor film using the gate electrode as a mask, a low concentration impurity region for one of the source and drain regions of which the impurity concentration is comparatively lower than that of the high concentration impurity region is formed in regions of the semiconductor film located below the extended part. At this time, low concentration impurity regions may be formed respectively in the source and drain regions.
Here, the distance (receding amount of the sidewalls of the gate electrodes) from the positions of the sidewalls of the resist film to the positions of the sidewalls of the gate electrode in the step of forming the gate electrode corresponds to the size (width) of the extended parts of the gate insulating film which extend from the sidewalls of the gate electrode to the outside. Then, this receding amount of the sidewalls of the gate electrode can be controlled with high precision through isotropic etching. Therefore, the size (width) of the extended parts of the gate insulating film can be determined with high precision. Then, since the low concentration impurity regions are formed by using gate electrode as a mask, the distance (width of the extended parts) between the sidewalls of these extended parts and the sidewalls of the gate electrode becomes approximately equal to the width of the regions where the low concentration impurity regions are formed. As a result, the dimensional precision of the low concentration impurity regions can be improved in comparison with the conventional case where the resist film is used as a mask. Therefore, the electric characteristics of the formed field effect transistor can be prevented, without fail, from fluctuating due to the fluctuation of the dimension of the low concentration impurity region. As a result of this, the reliability of the semiconductor device can be improved.
In addition, the resist film which has been used at the time of forming the gate electrode can again be used as a mask at the time of forming the high concentration impurity region and, therefore, the step can be simplified in comparison with a conventional case where a resist film is newly formed so as to be used as a mask for forming these high concentration impurity region.
In a manufacturing method for a semiconductor device according to the further aspect of this invention, a semiconductor film is formed on the substrate. An insulating film is formed on the semiconductor film. A conductive film is formed on the insulating film. A resist film which has a sidewall is formed on the conductive film. By partially removing the conductive film through etching using the resist film as a mask, gate electrode which have sidewall located inside the sidewall of the resist film are formed. By partially removing the insulating film through etching using the resist film as a mask, a gate insulating film including extended part which have sidewall located outside the sidewall of the gate electrode is formed. The resist film is removed. By implanting impurities into the semiconductor film using the gate insulating film as a mask, a high concentration impurity region for one of the source and drain regions is formed in the region of the semiconductor film apart from the sidewall of the extended part. At this time, the high concentration impurity regions may be formed respectively in the source and drain regions. Then, by implanting impurities into the semiconductor film by using the gate electrode as a mask, a low concentration impurity region for one of the source and drain regions of which the impurity concentration is comparatively lower than the high concentration impurity region are formed in the region of the semiconductor film located below the extended part. At this time, the low concentration impurity regions may be formed respectively in the source and drain regions.
In this manner, in the same way as the manufacturing method for a semiconductor device in the above still another aspect, the dimension of the extended part of the gate insulating film which extend from the sidewall of the gate electrode to the outside can be determined with an excellent precision. Then, since the width of the low concentration impurity region corresponds to the width of the extended part of the gate insulating film which extend from the sidewall of the gate electrode to the outside, it becomes possible to determined the width of the low concentration impurity region with an excellent precision. Therefore, a problem can be prevented from occurring that the electric characteristics of the semiconductor device such as field effect transistor, which include these low concentration impurity region, fluctuate due to the change of the width of the low concentration impurity region. As a result of this, the reliability of the semiconductor device can be improved.
In addition, since a gate insulating film is used as a mask at the time of forming the high concentration impurity region, it is not necessary to form a resist film so as to be used as a mask at the time of forming the high concentration impurity region such as in a prior art. As a result of this, the manufacturing method for the semiconductor device can be simplified.
In addition, since a resist film is not used as a mask at the time of forming the high concentration impurity region and low concentration impurity region, the resist film which is used as a mask will not change in quality by receiving the implantation of impurities. Therefore, a problem can be prevented from occurring that the resist film of which the quality has changed remain so that a predetermined structure can not be gained and the yield of products is lowered.
In the above described manufacturing method for a semiconductor device according to the further aspect, it is preferable to carry out the step of forming high concentration impurity regions and the step of forming low concentration impurity regions simultaneously.
In this case, the manufacturing method for a semiconductor device can be more simplified.
In the above described manufacturing method for a semiconductor device according to the still another and the further aspects, it is preferable to make remain an insulating film part, which has the film thickness thinner than the film thickness of the extended part of the gate insulating film, on the semiconductor film which is to become the high concentration impurity region in the step of forming a gate insulating film.
In this case, the insulating film part can be utilized as a protective film which prevents impurities such as impurity metals from entering into the high concentration impurity region. Therefore, a problem can be prevented, without fail, from occurring that the electric characteristics of the semiconductor device fluctuate due to the existence of such an impurity metal in the high concentration impurity region. As a result of this, the reliability of the semiconductor film can be more improved.
In the manufacturing method for a semiconductor device according to the above still another and further aspects, it is preferable for the impurities implanted to the low concentration impurity regions and high concentration impurity regions to be n type conductive impurities and it is preferable for the gate electrodes, the gate insulating film and the source and drain regions to form n type thin film field effect transistors. Prior to the step of forming the gate electrodes of the n type thin film field effect transistors, it is preferable to further include the step of forming the implemented p type thin film field effect transistor. In the step of forming the p type thin film field effect transistor, preferably a resist film is formed of the conductive film. By partially removing the conductive film using the resist film as a mask, the gate electrode of the p type thin film field effect transistor is formed and at the same time a conductive film is made to remain on the region where the n type thin film field effect transistor is to be formed. By using, as a mask, the gate electrode of the p type thin film field effect transistor and the conductive film which has been made to remain on the region where the n type thin film field effect transistor is to be formed, p type conductive impurities are implanted into the semiconductor film and, thereby, one of the source and drain regions of the p type thin film field effect transistor is formed. At this time, both of the source and drain regions may be formed.
Here, when the case where n type thin film field effect transistor is formed in advance and after that p type thin film field effect transistor is formed is taken into consideration, it is necessary to form a resist film so as to cover the n type thin film field effect transistor which has already been formed at the time when the step of forming one of the source and drain regions of the p type thin film field effect transistor is carried out. This is to prevent the electric characteristics of the n type thin film field effect transistor from changing due to the implanted p type conductive impurities. In the case that p type thin film field effect transistor are formed in advance as in the above, however, a conductive film remains on the regions where n type thin film field effect transistor is to be formed at the time when p type conductive impurities are implanted and this remaining conductive film is used as a mask and, therefore, the step of forming a resist film as a mask can be omitted. As a result of this, the manufacturing method can be designed to be simplified.
In the manufacturing method for a semiconductor device according to the above described still another and further aspects, it is preferable for the sidewall of the extended part to be formed so as to incline with respect to the main surface of the substrate in the step of forming a gate insulating film.
In this case, in the step of forming low concentration impurity region, the impurity concentration in the low concentration impurity region can be changed corresponding to the inclination of the sidewall of the extended part of the gate insulating film. That is to say, the impurity concentration can be made high comparatively in the region of the semiconductor film located below the part of which the film thickness of the extended part is comparatively thin because of the inclination of the sidewall of the extended part while the impurity concentration can be made comparatively low in the region of the semiconductor film beneath the part of which the film thickness of the extended part is comparatively thick. In this manner, the graduation of the impurity concentration can be formed in the low concentration impurity region so that the change of the electric field intensity in the low concentration impurity region can be made more gentle. As a result of this, the electric field concentration can be prevented from occurring so that a problem can be prevented from occurring where the semiconductor device malfunctions due to this electric field concentration. As a result, the reliability of the semiconductor device can be more improved.
In the manufacturing method for a semiconductor device according to the above described still another and further aspects, by partially removing an insulating film through isotropic etching in the step of forming a gate insulating film, it is preferable to incline the sidewall of the extended part with respect to the main surface of the substrate.
In this case, the sidewall of the extended part can be easily inclined with respect to the main surface of the substrate.
In the manufacturing method for a semiconductor device according to the still another and further aspects, it is preferable to incline the sidewall of the extended part with respect to the main surface of the substrate by using a resist receding method in the step of forming a gate insulating film.
In this case, the rate of the resist film being removed through etching can be changed by setting the manufacturing method conditions so as to modify the etching rate of the resist film. Therefore, the etching time of the part which is to become sidewall of the extended part of the insulating film can be modified by changing the rate of the resist film being removed. Thereby, the inclination angle of the sidewall with respect to the main surface of the substrate can be modified. As a result of this, it becomes possible to freely set the angle formed between the sidewall of the extended part and the main surface of the substrate.
In the manufacturing method for a liquid crystal display device according to the still further aspect of this invention, the manufacturing method for a semiconductor device according to the above described still another or further aspects is used.
In this manner, a semiconductor device which is used in the drive circuit or for display pixel of the liquid crystal display device can be easily formed so as to have high reliability. As a result of this, a liquid crystal display device which indicates stable display characteristics can be gained.
The foregoing and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings. | {
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This invention relates to switched reluctance motors and, more particularly, to an improved magnetic sensor for use with such motors.
Ring magnets are used in various industrial applications for sensing purposes. One of these applications is in dynamoelectric machines such as electric motors. In use on such motors, for example on switched reluctance motors (SRM's), the magnetic sensor comprises a ring installed on the rotor shaft of the motor so it turns as the rotor turns. When used with a Hall effect sensor, the magnetic sensor provides positional information which is used by control electronics for the motor to determine motor speed. This information is usable, in turn, to control switching between motor phases for commutation purposes. Conventionally, the magnet ring has opposed poles with the north and south poles subtending equal arcs about the circumference of the ring. This means that for each motor revolution, the Hall sensor sees each pole an equal amount of time. With respect to application of current to these polyphase motors, the effect is that the turn-on and turn-off portions of each cycle are approximately equal. In some polyphase SRM applications, it may be desirable to operate the phases so that there is a disparity in the length of these portions of the cycle. For example, in some applications it may desirable for the turn-on time of a SRM motor phase to last only 30%-45% of the turn-off dwell time. Or, in other applications, it may be desirable for the turn-off time to only be 30%-45% of the turn-on time. From a control standpoint, there is a problem in achieving this type of control using the present ring and sensor capabilities which are available. | {
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The Universal Mobile Telecommunications System (UMTS) is a radio communications network technology standard defined by the 3rd Generation Partnership Project (3GPP) organization.
In UMTS, a basic process of paging is related to two channels: a Paging Indication Channel (PICH), and a Paging Channel (PCH). The PICH is a fixed-rate physical channel (with the spread factor being 256), and the PICH is elaborated in 3GPP TS25.211 v4.2.0. FIG. 1 shows a frame structure of the PICH. The length of a PICH radio frame is 10 ms, which is composed of 300 bits. Of those bits, 288 bits (b0, b1, . . . , b287) bear the Paging Indication (PI), and the remaining 12 bits are reserved for future use and are not sent. One PI is composed of several bits. Depending on the length of one PI, each PICH frame may bear 18, 36, 72, or 144 PIs. The quantity of PIs carried in one PICH frame is denoted by Np. A Secondary Common Control Physical Channel (SCCPCH) bears the PCH. The PCH carries the specific content of the paging message, for example, User Equipment (UE) Identifier (ID), paging cause, and Circuit Switched (CN) domain ID. The PICH is correlated with the SCCPCH. A tail of the PICH radio frame is ahead of the SCCPCH correlated with PICH radio frame by 7680 chips.
FIG. 2 shows UE paging in a UMTS in the prior art.
After registering with a network, the UE is assigned to a paging group. Each paging group has a corresponding PI. When the UE in the paging group is paged, the PI corresponding to the paging group appears on the PICH periodically. After detecting the PI on the PICH, the UE starts receiving the specific paging message from the PCH through the SCCPCH. The upper layer of the protocol of the UE interprets the paging message.
The UE receives information in Discontinuous Reception (DRX) mode. Through the DRX mode, the UE is in a sleep mode when it is in an idle mode, and thus the power consumption is low. When the UE detects a PI of the UE, the UE awakens to receive the specific paging message. The UE monitors the PI periodically. If the period for monitoring the PI is longer, the chance for the UE to awaken is slim, and the UE is more energy-efficient. The UE, however, slowly responds to the network paging.
In UMTS, the UE obtains the content of the paging message in three steps:
Step 1. A System Frame Number (SFN) that includes the paging occasion is determined.
k indicates CN domain-specific DRX Cycle Length coefficient of the UE and the value range is 6≦k≦9; and a Paging Block Period (PBP) ranges from 4 to 64 in a TDD mode, and the PRB is 1 in the FDD mode. Therefore, in the idle mode, the DRX Cycle Length is calculated through Formula 2.1, and is expressed in radio frames.DRX Cycle Length=max(2k,PBP) Formula 2.1
Further, the SFN that includes the paging occasion of the UE is calculated through Formula 2.2.SFN={(IMSI div M) mod (DRX Cycle Length div PBP)}*PBP+n*DRX Cycle Length+Frame Offset Formula 2.2
In the above Formula 2.2, M is the quantity of SCCPCHs that bear the PCHs; Frame Offset is the offset of the frame, which is 0 in the FDD mode; n is a non-negative integer, and the value of n is acceptable only if the calculated value of SFN is less than the maximum value 4095 of the SFN allowed by the system.
Step 2.
A position of the PI to be decoded in the radio frame is determined.
The position of the PI in the radio frame is calculated through Formula 2.3 and Formula 2.4 according to an International Mobile Subscriber Identifier (IMSI) and a DRX Index of the UE.DRX Index=IMSI div 8192 Formula 2.3PI=DRX Index mod Np Formula 2.4
The UMTS employs an SFN-based glide mechanism to calculate the actual position (q) of the PI in the radio frame more precisely. The calculation of the position (q) is performed through Formula 2.5. The SFN changes with time. The position (q) of the PI glides with the change of the SFN.
q = ( PI + ⌊ ( ( 18 × ( SFN + ⌊ SFN / 8 ⌋ + ⌊ SFN / 64 ⌋ + ⌊ SFN / 512 ⌋ ) ) mod 144 ) × Np 144 ⌋ ) mod NP Formula 2.5
Step 3.
The PCH is read to obtain the specific content of the UE paging message.
Pq denotes the value of the PI in the position q. If Pq=0, it indicates that the PI is invalid, and the UE dose not need wakeup. If Pq=1, it indicates that the PI is valid, and the UE needs wakeup. According to the corresponding position relation between the PICH and the SCCPCH that bears the PCH, the specific content of the paging message is read.
As described above, in UMTS, the UE calculates the SFN that includes the paging according to the IMSI and the DRX Index, and uses Np to calculate the actual position (for example, bit position or bit group position) of the PI to be decoded in the radio frame. The UE reads the PCH according to the corresponding position relation between the PICH and the SCCPCH that bears the PCH, and obtains the specific content of the UE paging message.
Meanings of the symbols involved in the foregoing formula (applicable to the following text) are: mod means modulo operation, div means division and round-off, └ ┘ means round-down, and max (a, b) means a greater value among a and b.
A Long Term Evolution (LTE) project is intended for the mobile communication architecture to be developed by the 3GPP organization in the coming 10 years. FIG. 3 shows a structure of a radio frame applied in LTE. One frame is 10 ms, and is composed of 10 radio sub-frames, with each radio sub-frame being 1 ms. One radio sub-frame includes two timeslots, namely, each timeslot is 0.5 ms.
FIG. 4 shows a structure bearer of a radio sub-frame applied in LTE. One radio sub-frame includes 14 Orthogonal Frequency Division Multiplexing (OFDM) symbols, where the first three OFDM symbols bear the Physical Downlink Control Channel (PDCCH), and the last 11 OFDM symbols bear the Physical Downlink Shared Channel (PDSCH). The PDCCH bears the Paging Radio Network Temporary Identifier (P-RNTI), and the PCH mapped onto the PDSCH bears the specific content of the paging message.
The prior art described above reveals that: Compared with UMTS, LTE does not define PICH or PI, but defines a PCH for bearing the paging content. Meanwhile, the channel bearer unit changes from the 10-ms radio frame to the 1-ms radio sub-frame. There are many other systems like the LTE whose physical channel type and structure are different from those of the UMTS. In such systems, the computation of the paging occasion in UMTS in the prior art is not applicable any more, and such systems are unable to determine the paging time. | {
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The present invention relates generally to an integrated circuit (IC) design, and more particularly to a multiple-port static-random-access-memory (SRAM) cell structure with balanced read and write operation speeds and an improved noise margin.
SRAM devices have become increasingly popular as data storage units for high-speed communication devices, image processing devices, and other system-on-chip (SOC) products. A SRAM device is typically comprised of a logic circuit portion and a memory cell portion, which includes a plurality of cells arranged in one or more arrays. The SRAM cells, based on their structures, can be categorized as single-port cells, two-port cells, dual-port cells, and multiple-port cells. SRAM devices made of two-port, dual-port or multiple-port cells have become increasingly popular, as they are particularly suitable for parallel operations.
FIG. 1A schematically illustrates a conventional two-port SRAM cell 100 that is implemented with eight transistors. The conventional two-port SRAM cell 100 includes two PMOS transistors 102 and 104 and six NMOS transistors 106, 108, 110, 112, 114, and 116. The PMOS transistors 102 and 104 function as pull-up devices, while the NMOS transistors 106 and 108 function as pull-down devices. The NMOS transistors 110 and 112 function as pass-gate devices for read or write operations. The sources of the PMOS transistors 102 and 104 are both connected to a supply voltage Vcc, while the sources of the NMOS transistors 106 and 108 are both connected to a complementary supply voltage, such as ground or Vss. The gates of the PMOS transistor 102 and NMOS transistor 106 are coupled at a node 118, while their drains are also tied together at a node 120. The PMOS transistor 104 and the NMOS transistor 108 also having gates coupled together at the node 120, and drains at the node 118. The node 118 is coupled to a complementary read/write port bit line BLB via the NMOS transistor 112, which is controlled by a read/write word line WL. The node 120 is coupled to a read/write port bit line BL via the NMOS transistor 110, which is also controlled by the same read/write word line WL. In some special cases, this read/write port may serve only as a write port without the read function.
The read port portion of the conventional two-port SRAM cell 100 includes the NMOS transistor 114, which acts as a pull-down device and the NMOS transistor 116, which acts as a pass-gate device. A gate of the NMOS transistor 114 is connected to the node 120 (or 118), while its source is tied to the complementary supply voltage, such as ground or Vss. A high signal at the node 120 (or 118) can turn the NMOS transistor 114 on and ground the read port bit line BL when the NMOS transistor 116 is turned on by a high signal on the read word line WL.
FIG. 1B illustrates a layout diagram 122 of the metal routing for the conventional two-port SRAM cell 100 shown in FIG. 1A. The layout diagram 122 shows the metal routing for most of the interconnections used within the conventional two-port SRAM cell 100 of FIG. 1A. These interconnections include several power lines such as a supply voltage Vcc line 124, a complementary supply voltage Vss line 128, a landing pad 126 for another complementary supply voltage Vss line (not shown in this figure), and several bit lines and word lines. The bit lines shown are a read/write port bit line BL 130, a complementary read/write port bit line BLB 132, and a read port bit line BL 134. A read/write word line WL 136 is shown lined up in parallel with a read word line WL 138 on a metallization layer higher than that on which the Vcc line 124, the Vss line 128, the landing pad 126, the read/write port bit line BL 130, the complementary read/write port bit line BLB 132, and read port bit line BL 134 are constructed. Three landing pads 140, 142, and 144 are also implemented in parallel with the bit lines on the same metallization layer. The landing pads 140 and 142 are used for making connections with the read/write word line WL 136, while the landing pad 144 is used for making connections with the read word line WL 138.
One drawback of the conventional two-port SRAM cell 110 is that its layout structure is asymmetric. The read/write port bit line 130 is interposed between the landing pad 140 and the Vcc line 124. However, the complementary read/write port bit line BLB 132 is interposed between the Vss line 128 and the Vcc line 124. This asymmetric layout causes an imbalance of coupling capacitance between the read/write port bit line BL 130 and the complementary read/write port bit line BLB 132. As a result, the SRAM cell 100 suffers from a mismatch between read and write operations, induced by unwanted coupling capacitance and noise.
FIG. 2A schematically illustrates a conventional dual-port SRAM cell 200 that is implemented with eight transistors. The conventional dual-port SRAM cell 200 includes two PMOS transistors 202 and 204 and six NMOS transistors 206, 208, 210, 212, 214, and 216. The dual-port SRAM cell 200 utilizes two sets of bit lines and complementary bit lines for A port (first read/write port) and B port (second read/write port), respectively. The sources of the PMOS transistors 202 and 204 are both connected to a supply voltage Vcc, while the sources of the NMOS transistors 206 and 208 are both connected to a complementary supply voltage, such as ground or Vss. The gates of the PMOS transistor 202 and NMOS transistor 206 are coupled at a node 218, while their drains are also tied together at a node 220. The gates of the PMOS transistor 204 and the NMOS transistor 208 are also coupled together at the node 220, and their drains coupled at the node 218. The node 218 is coupled to an A port (first read/write port) complementary bit line BLB via the NMOS transistor 212 as well as to a B port (second read/write port) complementary bit line BLB via the NMOS transistor 216. The NMOS transistor 212 is controlled by an A port word line, while the NMOS transistor 216 is controlled by a B port word line. The node 220 is coupled to an A port bit line BL via the NMOS transistor 210 as well as to a B port bit line BL via the NMOS transistor 214. The NMOS transistor 210 is controlled by the A port word line while the NMOS transistor 214 is controlled by the B port word line.
FIG. 2B illustrates a layout diagram 222 of the metal routing for the conventional dual-port SRAM cell 200 shown in FIG. 2A. The layout diagram 222 shows interconnections including several supply lines such as a supply voltage Vcc line 224 and two complementary supply voltage Vss lines 226 and 228 as well as several bit lines and word lines. The bit lines shown are an A port bit line BL 230, a complementary A port bit line BLB 232, a B port bit line BL 234, and a complementary B port bit line BLB 236. An A port word line WL 238 is shown lined up in parallel with a B port word line WL 240. Two landing pads 242 and 244 are also implemented in parallel with the bit lines and supply voltage lines. The landing pad 242 is used for making connections with the A port word line WL 238, while the landing pad 244 is used for making connections with the B port word line WL 240.
Although the conventional dual-port SRAM cell 200 provides a symmetrical layout structure, there is still a balancing issue induced by the coupling capacitance on the bit lines. For example, the placements of the A port bit line BL 230 between the complementary supply voltage Vss line 226 and the landing pad 242, and the placement of the complementary write port bit line BLB 232 between the complementary supply voltage Vss line 226 and the supply voltage Vcc line 224 can create an imbalance of coupling capacitance. The same coupling capacitance imbalance issue may occur for the B port bit line BL 234 and the complementary B port bit line BLB 236, since the B port bit line BL 234 is placed between the complementary supply voltage Vss line 228 and the landing pad 244 and the complementary B port bit line BLB 236 is placed between the complementary supply voltage Vss line 228 and the supply voltage Vcc line 224. An imbalance between the coupling capacitance of the interconnection wires may result in an undesired level of noise margin, thereby hindering the operation speed of the cell.
As such, desirable in the art of integrated circuit designs are new SRAM cell structures with balanced read and write operation speeds and an improved noise margin. | {
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1. Field of the Invention
The present invention relates to a clamp for a cord.
2. Prior Art
U.S. Pat. No. 3,765,061 discloses a clamp cleat with two cam members spring loaded towards each other by coil springs. U.S. Pat. No. 2,315,196 discloses a pair of spring loaded movable jaws with extensions to manually move the jaws away from each other. | {
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Data may be transmitted between varieties of different devices in many different ways. For example, a basic computing device, such as a personal computer may wirelessly transmit data to and/or receive data from another basic computing device via a wireless network. In another example, a utility meter (e.g., a water meter, a gas meter, and/or an electricity meter) may transmit data (e.g., consumption data, error data, firmware upgrade data, etc.) to other utility meters, collector nodes, and/or remote facilities via a wireless network. | {
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Numerous systems have been developed over the years which utilize telephone lines, power lines and CATV lines for carrying signals of all types representing alarm conditions, data readings, survey data, and various types of control signals to initiate control functions. Such systems are attractive from an economical point of view in that they take advantage of existing transmission media and, therefore, like radio and television, make possible long-range communications and transmission of control and data signals without large expenditures for the transmission media itself. However, such systems have to date been used for the most part for the transmission of alarm, survey and control signals and have been generally unavailable to the individual subscriber for handling a broader range of data communications and services, and those systems which are in use require dedicated access to the data service, which is expensive and inefficient.
Television has greatly increased the communication of data to the home over that provided by radio in that it involves both a visual and aural commuication. However, commercial television, like radio, provides a unilateral service in that the viewer basically is capable of receiving only that which others wish to transmit at any given time. Prior services systems which utilized the telephone, power and CATV lines were also, for the most part, unilateral systems in that such systems were designed to transmit information only in a single direction, i.e, from the subscriber to power, security and other service companies. In those systems designed for remote meter reading and audience survey, control signals were transmitted to individual subscribers and in response thereto the data was transmitted automatically to the collecting agency; however, in these systems the subscriber had little or no control over the information being transmitted and certainly had no power or capability of envoking the receipt of data on request.
The world is presently at the doorstep of the next great advance in the extension of data services to the private sector of the community. Data processing systems have already become the indispensable tool of the business and scientific communities, providing word processing, data retrieval, systems analysis, reservations control and may other services on various levels of sophistication. However, such services can also be made available to the individual subscriber in his home by way of available telephone lines. The provision of multiple services to the telephone subscriber represents a fascinating prospect for the future, which encompasses a broad range of technologies for delivering such services, including satellite, coaxial cable and fiber optic systems.
However, in systems designed to handle both alarms and data communication, problems are encountered in handling both types of signals without undue complexity and without having to buffer the data and interleave it with the alarms. In addition, where multiple services are to be made available to the subscriber, some means must be provided to access different types of terminals at the customer premises on a selective basis in a way which is compatible with the reporting of alarms and other conditions as desired.
It is therefore a broad object of the present invention to provide a multiple service broadband system for existing telephone local loop service.
It is a further object of the present invention to provide a system of the type described which will be transparent to normal telephone service while providing a multiplicity of new services including data service communication, alarm communication and energy management.
It is a further object of the present invention to provide a system of the type described which includes a modular data service switching arrangement integrated into the basic security system switch to permit faster switchover and interleaving of data service and alarm and automatic meter reading data.
It is still another object of the present invention to provide a system of the type described in which data service support is independent from data rate code, format and protocol of the data service system.
It is still a further object of the present invention to provide a system of the type described which operates on the basis of a sophisticated communications protocol with error detection and retransmission to minimize false alarms and erroneous data.
It is another object of the present invention to provide a system of the type described having increased flexibility and expandability to allow for system growth in terms of both services and the number of subscribers served. | {
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This disclosure relates generally to a method and apparatus for improved display of digital mammographic images.
Digital mammographic images or mammograms are usually presented as gray scale images having individual pixels, with each pixel having a pixel value corresponding to a specific gray scale value. These gray scale values may lie within a range of values between a minimum value of, for example, 0 (black) and a maximum value of, for example, 225 (white). The edge length of a typical mammogram is approximately 2000 to 4000 pixels, and the dissolution of a typical mammogram is approximately 10 line pairs/mm and/or 0.1 mm/pixel.
A mammographic imaging system may be coupled to a workstation, for example, a PACS (Picture Archiving and Communication System) workstation, on which a mammogram may be viewed and reviewed by a physician or other medical professional. Mammography assigned PACS workstations usually have high resolution monitors, which are able to represent the high volume range and the comparatively high resolution of mammographic images.
Mammographic imaging systems generate raw mammograms containing measured data. These raw mammograms exhibit a global image characteristics with a comparatively high contrast in a boundary region of the measured object (i.e., the boundary region of the breast) and a relatively low contrast inside the measured object (i.e., the inside the breast). Conventional PACS workstations typically include tools for selecting parts of the whole gray scale level range and displaying these parts with maximum contrast through window level settings. Gray scale level ranges outside of the selected gray scale level window are mapped to the smallest or highest possible gray scale level, which means that information contained in these outside ranges is no longer displayed. Alternatively, nonlinear transfer functions represented through so called lookup tables may be applied to the raw mammogram modifying the global image characteristics in order to achieve a better over-all-contrast. Since the available total range of gray scale levels is fixed, a contrast enhancement for a selected part of the gray scale level range leads to a decrease of contrast in other gray level ranges. Therefore, an optimal display of all gray scale levels of the mammogram with optimal contrast and sharpness cannot be achieved by applying window level settings and/or lookup tables.
In the case of a mammogram a fundamental problem results in the fact that it is difficult to visualize structures within the breast. At the same time, structures within the background do not have to be visualized. The actual interesting structures are represented within the breast by pixel values, which do not use the entire range of values available, but use values within a comparatively small range. Therefore, the contrast between the pixels of the actual interesting structures is thus comparatively small.
Well known level and window functions use a global adjustment of the contrast between the pixels for contrast optimization, as for example the contrast between pixels with pixel values in a certain range of values is increased (the range of values is spread), all pixels with pixel values outside of this range of values however on the minimum or maximum pixel value is at the same time are set In this way, the contrast for certain structures, for example within the represented close gland fabric of a breast may be optimized, while the contrast within other ranges, received at the same time, are not optimal and may be within set ranges, so that the information is not represented into individual ranges any longer.
Therefore, there is a need for a method and apparatus for an intuitive way for a physician or other medical professional to locally optimize the contrast of a mammographic image in a particular portion of the mammographic image. | {
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As cellular telephones incorporate multimedia functions such as still and video capture, video playback (e.g., MPEG 4) and/or stereo audio playback (e.g., MP3 files), memory capacity becomes an essential limitation. Nonvolatile memories with non-moving mechanisms such as Flash memories have been utilized by cellular telephones for storage of multimedia files. Flash memories and like devices, however, have limited capacity for storing a large number of multimedia files such as music files, movies, video recordings and so on. Consequently, an end user of a cellular telephone often has to manage the phone's memory by downloading or deleting multimedia files to make room for other files on a frequent basis.
A need therefore arises for a storage medium for a cellular telephone that improves the aforementioned deficiency in the art. | {
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The present invention relates to an electric tracklaying gear and the use thereof for a self-propelled working machine, preferably for a construction or earth-moving machine or a surface mining machine such as Surface Miner, which includes an endlessly circulating track chain which can be driven by a crawler drive that is arranged within the path of circulation of the track chain.
Such tracklaying gears are used for various machines of the type mentioned above such as hydraulic or cable excavators, mobile crawler cranes, bulldozers, asphalt milling machines or Surface Miners. The endlessly circulating track chain traditionally is a link chain made of a metallic material, but it can also mean a rubber chain or a similarly constructed moving belt which circulates endlessly.
To protect the crawler drive against external damages and not increase the track width of the vehicle beyond the outer sides of the link chains, the crawler drive for driving the link chain is integrated into the tracklaying gear, in particular such that the crawler drive is arranged within the path of circulation of the track chain, so that no or at least no significant protrusion does exist. However, this results in various problems.
On the one hand, the drive unit must have a very short overall length, so as not to laterally protrude beyond the track chain. The available installation space substantially is defined by the width of the track chain, so that longer motors with transmission units connected thereto often are too long or could only be mounted with a lateral protrusion.
On the other hand, cooling the drive units often is not possible to a sufficient extent, since a surface cooling or open-circuit cooling is not expedient for reasons of dust input. In addition, the crawler drive in use can also partly be submerged in water, so that a closed design of the drive units must be provided. In the case of forced ventilations, in addition, a strong generation and agitation of dust can be caused by a large stream of air emerging from the drive unit depending on the soil at the site of use, which is not acceptable in most uses.
Due to their short overall length and easy coolability, hydrostatic motors therefore are often used as crawler drive, which drive the tumbler of the tracklaying gear via a planetary transmission and are provided with a hydraulically ventilated multi-disc brake. Due to the small overall length of such hydrostatic motors, it mostly is possible to keep the axial overall length of motor and transmission so short that the entire drive unit can completely be accommodated in the region of the chain width and thus can be well protected against external influences and damages for example by stones.
In addition it has already been considered to use electric motors instead of such hydrostatic drives as crawler drive. However, this is not easily possible for the above-mentioned reasons and problems.
Usually, electric motors are cooled by surface cooling or open-circuit cooling with forced ventilation or self-ventilation. These known cooling solutions are, however, not expedient for use in tracklaying gears of construction machines, surface milling cutters, asphalt milling machines, excavators or the like for reasons of dust input which can be produced by a tracklaying gear operating in or on the soil. In addition, in use the drive might also partly be submerged in water, so that a closed design of the motor is preferred. On the other hand, a strong generation and agitation of dust can be caused by a large stream of air emerging from the motor depending on the soil at the site of use, which is not acceptable in most uses.
In so far, it has already been considered to provide for sucking in cooling air via a kind of snorkel at a higher point of the machine, since less dust is generated there and hence a reduced dust input into the motor is achieved. However, this does not solve the problem of the generation of dust by the emerging cooling air.
The generation of dust can largely be avoided with a hermetically closed motor in which the emerging cooling air is contained in a conduit and recirculated to an outlet at an elevated point on top of the machine. Nevertheless, a rest of dust input into the motor will remain, since the intake conduit cannot be designed arbitrarily high.
Therefore, it has already been considered to employ a hermetically closed motor, in which the air is guided in a closed air circuit and is cooled by means of a heat exchanger with an air inlet and outlet located at the top. However, this involves the problem that the required large amounts of air require very large conduit cross-sections down into the tracklaying gear and back, which in terms of space can hardly be accommodated and can only be protected against mechanical damages with corresponding difficulties. | {
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This invention relates broadly to valves and fluid flow-control members, and more particularly to plug valves. More particularly still, the invention relates to plug valves which are fully lined with corrosion-resistant material, for example, the fluorocarbon polymer known as polytetrafluoroethylene (PTFE).
The problems and difficulties associated with conduit systems used to convey highly corrosive chemicals and like fluids have for many years proved to be extremely troublesome to those working in this field, and this is particularly true with respect to valves used in such an environment. Many approaches have been suggested in the past for overcoming these problems, or at least for diminishing them. Basically, it is fair to say that the principal effort embodied in these approaches has been to line the interior of the various conduit system parts, including the conduit itself, in-line fittings, and even the valves used in the system, with some non-corrosive or corrosion-resistant material.
For example, lining a valve body for such a purpose was suggested at least as long as 40 years ago (U.S. Pat. No. 1,827,266), and many different forms of this approach have since been suggested. For the most part, development has taken place through suggested uses of plastic resins for lining materials, since such materials are substantially inert chemically and, additionally, many have lubricous surface characteristics which greatly facilitate smooth and easy operation of tightly-fitting valve members.
In relatively recent times, polytetrafluoroethylene has emerged as the most favored material for forming such linings, due to its various superior qualities which are now relatively well-known. Very often, a preformed tube or other such element made of PTFE is inserted or otherwise mechanically attached in place over a given surface which is to be protected in order to form the desired lining, although other processes are also known. Valves and valve components, as well as conduit fittings and the like, using such material as a lining or coating have heretofore been described or suggested, for example, in the United States Pat. Nos. to Johnson (3,073,336), Chu (3,148,896), McFarland (3,205,113), Boteler (3,206,530), Keen (3,223,763), Yost (3,227,174), Lowrey (3,334,650), Schenck (3,438,388) and Schenck et al. (3,459,213). In certain of these prior patents, the concept is advanced of using granular or powdered PTFE for forming the lining member, in which process the powdered material is compressed into a preform and subsequently sintered so as to coalesce it into a homogeneous lining or coating which is said to be of substantially uniform density and of substantially completely fluid-impervious characteristics. This basic technique of molding powdered materials has long been used in ceramics and metallurgy, and such technique has also been long known as a way of utilizing powdered PTFE, even prior to the usage of such material in valves or fittings. For example, reference is made to the United States patents to Benning et al. (2,400,094) and Cresap (2,929,109), as well as to the Canadian Patent to Deakin (566,811).
Notwithstanding the foregoing, the total successfulness of fully-lined valves continues to remain considerably less than that which is needed and desired. Principally, the reason for this is that known types of PTFE liners are not sufficiently reliable and are subject to leakage of the corrosive fluids, as by major rupture under heat and pressure, or through the development of pinholes and other minor voids or imperfections or unduly thin sections, through which the corrosive fluid may leak or pass by permeation. This remains true despite careful manufacturing procedures and, to a certain extent, is believed to be somewhat inherent in the manufacturing processes practiced heretofore, which are themselves somewhat involved, complicated, and subject to a relatively high degree of failure or reject parts. | {
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Emergency lighting systems are commonly used in buildings or other structures to provide a source of illumination when the main power circuitry is disrupted, therby disabling any illumination devices attached to that circuit. Virtually any building to which public access is permitted is equipped with numerous emergency lighting systems to provide a source of at least limited illumination when conventional line circuit network becomes non-functional, and therefore the standard illumination devices are inoperable.
2. Prior Art
Prior art emergency lighting systems are generally equipped with storage batteries which produce energy for incandescent lamps of 10 watts or more for a given period of time. The requirement for these emergency lighting systems, as well as the amount and duration of this illumination is mandated by various ordinances and rules. It is well-known by one possessing ordinary skill in art that incandescent lamps have a relatively low light consumption characteristic which neccessitates a relatively large size battery and therefore a high-powered battery charger. As a consequence, the entire prior art emergency lighting systems have a relatively short life period with the typical low voltage incandescent lamp employed therewith. Therefore, the prior art system requires constant monitoring to ensure that the incandescent lamps utilized therewith, as well as the emergency lighting system are still functioning. | {
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Quick connect and quick disconnect systems, also referred to as coupler systems, are widely utilized in wide variety of industrial, household, medical, hydraulic, pneumatic, and commercial applications. One application for coupler systems are for garden and lawn use. Another application for coupler systems is for automotive nozzles and hoses for fuel delivery, such as gasoline and other petroleum-based products. Yet another application for coupler systems is for vacuum cleaners, power tools, or other devices for collecting debris or dispensing fluid. Fluids, such as beverages, fuels, liquid chemicals, fluid food products, gases, water, and air are also frequently delivered from one vessel to another through a fluid system.
Coupler systems typically include a first connector and a second connector. The first connector is typically associated with a fluid device and the second connector is typically associated with a fluid conductor. For example, a coupler system is configured for use with a fluid device provided as a water spray nozzle and a fluid conductor provided as a hose. The first connector is connected to the spray nozzle and the second connector is connected to the hose. The coupler system simplifies connecting and disconnecting the spray nozzle from the hose, as described below, with reference to a typical connection of a spray nozzle to a hose.
The typical hose includes an internally threaded end portion that is connected to a spigot and an opposite externally threaded end portion to which fluid devices are connectable. To connect a typical spray nozzle to the externally threaded end portion, first the user stops the flow of water through the hose. Next, the user aligns connection threads of the spray nozzle with threads of the externally threaded end portion of the hose. Then the user repeatedly rotates the spray nozzle relative to the hose to mechanically and to fluidly connect the spray nozzle to the hose. Some users require a separate hand tool, such as a wrench, to rotate the spray nozzle or to stabilize the hose during the rotation of the spray nozzle. Hoses available in Europe typically do not require a threaded feature or a barb feature. Instead, the connector is mechanically connected to the hose or the fluid system using a compression fitting method. Of course, other forms of fittings are possible.
The above described process is inconvenient since the supply of water through the hose is stopped before connection of the spray nozzle is made. Second, the process requires sufficient strength and dexterity to rotate the spray nozzle. Third, the connection of the spray nozzle to the hose is subject to leaking.
Coupler systems seek to simplify the above described process by making connection of the spray nozzle to the hose fast and easy. Coupler systems typically include a male connector and a female connector one of which includes a locking feature. To connect the connectors, the male connector is received by the female connector and the locking feature is engaged. To disconnect the connectors, the locking feature is disengaged and the male connector is separated from the female connector. The structure of the male connector and the female connector, as well as the method of operating the locking feature, varies between different models of coupler systems.
Even though coupler systems seek to simplify connection of a fluid device to a fluid conductor, coupler systems typically suffer from numerous problems. First, some coupler systems include a locking feature that is difficult disengage, especially when the fluid in the fluid conductor is under pressure. For example, conventional quick connector products having a shut off feature require significant force to overcome line pressure, thus becoming an issue to the user using the product. Second, some coupler systems are quick to connect and to disconnect, but are prone to leaking. Third, some coupler systems are expensive and time consuming to manufacture. Accordingly, the time savings provided by some coupler systems are at a cost of being difficult to disengage, leaky, and expensive.
In some coupler systems, when the male connector is disconnected from the female connector a burst of pressurized water is expelled from the female connector before a valve in the female connector terminates the flow of water therethrough. The burst of pressurized water is especially prevalent when the fluid conductor and the fluid device are partially filled with air. The burst of pressurized water is typically only a minor inconvenience; however, some users desire a coupler system that is not prone to leaky during the disconnection process.
In addition to being able to quickly connect and disconnect a fluid device from a fluid conductor, some users desire the ability to control the flow of the fluid through the fluid device. For this reason manufactures have developed adjustable valves, which are placed in series with the fluid device and the fluid conductor. The adjustable valve is typically moveable between a position of low fluid flow and a position of high fluid flow. These types of adjustable valves work well for controlling fluid flow; however, the typical adjustable valve is not usable in combination with the typical coupler system. Additionally, even if the adjustable valve is usable with the coupler system it typically results in a cumbersome collection of components that is subject to leaking.
For at least the above-described reasons, further developments in the area of quick connect and quick disconnect systems for fluid systems are desirable. | {
"pile_set_name": "USPTO Backgrounds"
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Solar concentration aims to decrease the use of expensive photovoltaic materials by reducing the solar cell size and adding an optical system to focus the sunlight onto the solar cell. This reduces the quantity of solar cell material used in the system at the expense of adding the need for a tracking system in order to keep the focal spot on the reduced solar cell. State of the art solar concentrators, mostly using Fresnel lenses or parabolic mirrors, need a tracking precision of less than 1° in two dimensions in order to cover the diurnal and seasonal variations of the sun's position. Such a tracking device consumes energy, decreasing the overall system efficiency, and adds to the cost of the system, thereby diminishing the savings from a smaller solar cell. Accordingly, in light of these deficiencies of the background art, additional, improved, and low-cost systems, devices and methods for solar light concentration and self-tracking are strongly desired. In this respect, self-tracking concentrators have the potential to increase the acceptance angle of a solar concentration system and thereby greatly reduce the need for tracking. | {
"pile_set_name": "USPTO Backgrounds"
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The reliability of telecommunication systems that users have come to expect and depend on is based, in part, on the systems' reliance on redundant equipment and power supplies. Telecommunication switching systems, for example, route tens of thousands of calls per second. The failure of such systems, due to, for instance, the loss of incoming AC power, may result in a loss of millions of telephone calls and a corresponding loss of revenue.
Power plants, such as battery plants, attempt to alleviate the power loss problem by providing the telecommunication system with a backup power supply for use in the event that the incoming AC power is interrupted. Since the backup power supply is often called upon to provide power to the load for durations longer than just a few seconds, the implementation of a battery backup system has a significant impact on both the performance and the cost of the power plant.
A concern with respect to battery plants is managing the transition from a normal or primary mode of operation to a backup mode of operation requiring the use of a backup power system. A control circuit used to manage such a transition is required to detect when there is an absence of primary power to a primary power system and switch to the backup power system. Typically, the primary power system and the backup power system are voltage sources having a low output impedance. Since the outputs of the low output impedance voltage sources cannot generally be directly coupled together without causing serious circulating current problems (resulting in probable component damage), the transition must be orchestrated carefully. This requirement typically increases the complexity and therefore the cost of such control circuits.
Another perhaps more strategic concern is the ability of the power system to continue to operate when a component or collection of components experience a fault. Present fault-tolerant structures often depend on a multiplicity of completely redundant circuits or systems wherein one or more of such circuits or systems may be completely removed from the system if they become faulted. This approach, of course, increases the overall cost proportionally and may raise the overall reliability only marginally depending on a particular configuration.
Accordingly, what is needed in the art is a dual input power supply and a method of operating the power supply that overcomes the deficiencies of the prior art. | {
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This invention relates to electron beam lithography apparatus used for the manufacture of semiconductor integrated circuits.
Electron beam exposure tools have been used for lithography in semiconductor processing for more than two decades. The first e-beam exposure tools were based on the flying spot concept of a highly focused beam, raster scanned over the object plane. The electron beam is modulated as it scans so that the beam itself generates the lithographic pattern. These tools have been widely used for high precision tasks, such as lithographic mask making, but the raster scan mode is found to be too slow to enable the high throughput required in semiconductor wafer processing. The electron source in this equipment is similar to that used in electron microscopes, i.e. a high brightness source focused to a small spot beam.
More recently, a new electron beam exposure tool was developed based on the SCALPEL (SCattering with Angular Limitation Projection Electron-beam Lithography) technique. In this tool, a wide area electron beam is projected through a lithographic mask onto the object plane. Since relatively large areas of a semiconductor wafer (e.g. 1 mm2) can be exposed at a time, throughput is acceptable. The high resolution of this tool makes it attractive for ultra fine line lithography, i.e sub-micron.
The requirements for the electron beam source in SCALPEL exposure tools differ significantly from those of a conventional focused beam exposure tool, or a conventional TEM or SEM. While high resolution imaging is still a primary goal, this must be achieved at relatively high (100-1000 xcexcA) gun currents in order to realize economic wafer throughput. The axial brightness required is relatively low, e.g. 102 to 104 Acmxe2x88x922srxe2x88x921, as compared with a value of 106 to 109 Acmxe2x88x922srxe2x88x921 for a typical focused beam source. However, the beam flux over the larger area must be highly uniform to obtain the required lithographic dose latitude and CD control.
A formidable hurdle in the development of SCALPEL tools was the development of an electron source that provides uniform electron flux over a relatively large area, has relatively low brightness, and has an electron emitter with a sufficient lifetime to avoid excessive downtime. Lanthanum hexaboride (LaB6) emitters in a modified Wehnelt electron gun arrangement were found to be promising for this application, and the first SCALPEL tools were built with these electron sources. Efforts to improve the uniformity of the electron emission profile over the surface of the LaB6 have continued, but with limited success. Replacement of the LaB6 emitter with a simple tantalum disk was found to improve the surface emission uniformity and stability. While SCALPEL systems are regarded as highly successful fine line lithographic exposure tools, there is a continuing search for electron gun designs that improve the efficiency and uniformity of the electron beam source.
We have developed a new electron beam source for SCALPEL systems which uses a modified Wehnelt gun design wherein the Wehnelt electrode is biased in reverse of the Wehnelt gun used in conventional SCALPEL tools. The modified Wehnelt gun also has a tapered opening, with the electron emitter recessed into the tapered opening. The result of these modifications is a laminar electron beam with low brightness and essentially no crossover. These beam properties are ideal for a SCALPEL tool, which does not require focusing optics in the near field.
The invention will be described more specifically in the following detailed description which, taken with the drawing, will provide a greater understanding of the features that distinguish this invention from conventional electron beam sources. | {
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Cable termination tooling may comprise e.g. cutting tools, stripping tools and crimping tools. Some tools only have one of the above functions, whereas other tools have two or three of the above functions. Tools for cable termination may be hand tools or powered tools, e.g. hydraulically powered tools. Cable termination is required e.g. for connecting a cable or a wire to power, coaxial, fiber-optic or modular connectors.
When crimping, a connector i.e. a terminal, splice, contact or a similar device is mechanically secured to a cable—e.g to a conductor such as a wire—by deformation so that a solid joint having reliable mechanical and electrical connection is formed. The crimping operation resulting in a crimped joint is e.g. performed using crimping dies.
DE 198 58 719 A1 shows a crimping tool having an two-part-frame for adjusting the position of the crimping dies which crimping dies are pivotally mounted and axially fixed to the body of the crimping tool, i.e. the pivot points for the crimping dies are fixed relative to the body of the tool. Thus, a sliding movement occurs on the contact surface between the crimping dies and the workpiece to be crimped during the crimping operation. | {
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The number and variety of portable and mobile devices in use have exploded in the last decade. For example, the use of mobile phones, tablets, media players etc. has become ubiquitous. Such devices are generally powered by internal batteries and the typical use scenario often requires recharging of batteries or direct wired powering of the device from an external power supply.
Most present day systems require a wiring and/or explicit electrical contacts to be powered from an external power supply. However, this tends to be impractical and requires the user to physically insert connectors or otherwise establish a physical electrical contact. It also tends to be inconvenient to the user by introducing lengths of wire. Typically, power requirements also differ significantly, and currently most devices are provided with their own dedicated power supply resulting in a typical user having a large number of different power supplies with each being dedicated to a specific device. Although, the use of internal batteries may avoid the need for a wired connection to a power supply during use, this only provides a partial solution as the batteries will need recharging (or replacing which is expensive). The use of batteries may also add substantially to the weight and potentially cost and size of the devices.
In order to provide a significantly improved user experience, it has been proposed to use a wireless power supply wherein power is inductively transferred from a transmitter coil in a power transmitter device to a receiver coil in the individual devices.
Power transmission via magnetic induction is a well-known concept, mostly applied in transformers, having a tight coupling between primary transmitter coil and a secondary receiver coil. By separating the primary transmitter coil and the secondary receiver coil between two devices, wireless power transfer between these becomes possible based on the principle of a loosely coupled transformer.
Such an arrangement allows a wireless power transfer to the device without requiring any wires or physical electrical connections to be made. Indeed, it may simply allow a device to be placed adjacent to or on top of the transmitter coil in order to be recharged or powered externally. For example, power transmitter devices may be arranged with a horizontal surface on which a device can simply be placed in order to be powered.
Furthermore, such wireless power transfer arrangements may advantageously be designed such that the power transmitter device can be used with a range of power receiver devices. In particular, a wireless power transfer standard known as the Qi standard has been defined and is currently being developed further. This standard allows power transmitter devices that meet the Qi standard to be used with power receiver devices that also meet the Qi standard without these having to be from the same manufacturer or having to be dedicated to each other. The Qi standard further includes some functionality for allowing the operation to be adapted to the specific power receiver device (e.g. dependent on the specific power drain).
The Qi standard is developed by the Wireless power Consortium and more information can e.g. be found on their website: http://www.wirelesspowerconsortium.com/index.html, where in particular the defined Standards documents can be found.
The Qi wireless power standard describes that a power transmitter must be able to provide a guaranteed power to the power receiver. The specific power level needed depends on the design of the power receiver. In order to specify the guaranteed power, a set of test power receivers and load conditions are defined which describe the guaranteed power level for each of the conditions.
Qi originally defined a wireless power transfer for low power devices considered to be devices having a power drain of less than 5 W. Systems that fall within the scope of this standard use inductive coupling between two planar coils to transfer power from the power transmitter to the power receiver. The distance between the two coils is typically 5 mm. It is possible to extend that range to at least 40 mm.
However, work is ongoing to increase the available power, and in particular the standard is being extended to mid-power devices being devices having a power drain of more than 5 W.
The Qi standard defines a variety of technical requirements, parameters and operating procedures that a compatible device must meet.
Communication
The Qi standard supports communication from the power receiver to the power transmitter thereby enabling the power receiver to provide information that may allow the power transmitter to adapt to the specific power receiver. In the current standard, a unidirectional communication link from the power receiver to the power transmitter has been defined and the approach is based on a philosophy of the power receiver being the controlling element. To prepare and control the power transfer between the power transmitter and the power receiver, the power receiver specifically communicates information to the power transmitter.
The unidirectional communication is achieved by the power receiver performing load modulation wherein a loading applied to the secondary receiver coil by the power receiver is varied to provide a modulation of the power signal. The resulting changes in the electrical characteristics (e.g. variations in the current draw) can be detected and decoded (demodulated) by the power transmitter.
Thus, at the physical layer, the communication channel from power receiver to the power transmitter uses the power signal as a data carrier. The power receiver modulates a load which is detected by a change in the amplitude and/or phase of the transmitter coil current or voltage. The data is formatted in bytes and packets.
More information can be found in chapter 6 of part 1 the Qi wireless power specification (version 1.0).
Although Qi uses a unidirectional communication link, it has been proposed to introduce communication from the power transmitter to the power receiver. However, such a bidirectional link is not trivial to include and is subject to a large number of difficulties and challenges. For example, the resulting system still needs to be backwards compatible and e.g. power transmitters and receivers that are not capable of bidirectional communication still need to be supported. Furthermore, the technical restrictions in terms of e.g. modulation options, power variations, transmission options etc. are very restrictive as they need to fit in with the existing parameters. It is also important that cost and complexity is kept low, and e.g. it is desirable that the requirement for additional hardware is minimized, that detection is easy and reliable, etc. It is also important that the communication from the power transmitter to the power receiver does not impact, degrade or interfere with the communication from the power receiver to the power transmitter. Furthermore, an all-important requirement is that the communication link does not unacceptably degrade the power transfer ability of the system.
Accordingly, many challenges and difficulties are associated with enhancing a power transfer system such as Qi to include bidirectional communication.
System Control
In order to control the wireless power transfer system, the Qi standard specifies a number of phases or modes that the system may be in at different times of the operation. More details can be found in chapter 5 of part 1 the Qi wireless power specification (version 1.0).
The system may be in the following phases:
Selection Phase
This phase is the typical phase when the system is not used, i.e. when there is no coupling between a power transmitter and a power receiver (i.e. no power receiver is positioned close to the power transmitter).
In the selection phase, the power transmitter may be in a stand-by mode but will sense in order to detect a possible presence of an object. Similarly, the receiver will wait for the presence of a power signal.
Ping Phase:
If the transmitter detects the possible presence of an object, e.g. due to a capacitance change, the system proceeds to the ping phase in which the power transmitter (at least intermittently) provides a power signal. This power signal is detected by the power receiver which proceeds to send an initial package to the power transmitter. Specifically, if a power receiver is present on the interface of the power transmitter, the power receiver communicates an initial signal strength packet to the power transmitter. The signal strength packet provides an indication of the degree of coupling between the power transmitter coil and the power receiver coil. The signal strength packet is detected by the power transmitter.
Identification & Configuration Phase:
The power transmitter and power receiver then proceeds to the identification and configuration phase wherein the power receiver communicates at least an identifier and a required power. The information is communicated in multiple data packets by load modulation. The power transmitter maintains a constant power signal during the identification and configuration phase in order to allow the load modulation to be detected. Specifically, the power transmitter provides a power signal with constant amplitude, frequency and phase for this purpose (except from the change caused by load-modulation).
In preparation of the actual power transfer, the power receiver can apply the received signal to power up its electronics but it keeps its output load disconnected. The power receiver communicates packets to the power transmitter. These packets include mandatory messages, such as the identification and configuration packet, or may include some defined optional messages, such as an extended identification packet or power hold-off packet.
The power transmitter proceeds to configure the power signal in accordance with the information received from the power receiver.
Power Transfer Phase:
The system then proceeds to the power transfer phase in which the power transmitter provides the required power signal and the power receiver connects the output load to supply it with the received power.
During this phase, the power receiver monitors the output load conditions, and specifically it measures the control error between the actual value and the desired value of a certain operating point. It communicates these control errors in control error messages to the power transmitter with a minimum rate of e.g. every 250 msec. This provides an indication of the continued presence of the power receiver to the power transmitter. In addition the control error messages are used to implement a closed loop power control where the power transmitter adapts the power signal to minimize the reported error. Specifically, if the actual value of the operating point equals the desired value, the power receiver communicates a control error with a value of zero resulting in no change in the power signal. In case the power receiver communicates a control error different from zero, the power transmitter will adjust the power signal accordingly.
A potential problem with wireless power transfer is that power may unintentionally be transferred to e.g. metallic objects. For example, if a foreign object, such as e.g. a coin, key, ring etc., is placed upon the power transmitter platform arranged to receive a power receiver, the magnetic flux generated by the transmitter coil will introduce eddy currents in the metal objects which will cause the objects to heat up. The heat increase may be very significant and may indeed result in a risk of pain and damage to humans subsequently picking up the objects.
Experiments have shown that metal objects positioned at the surface of a power transmitter can reach an undesired high temperature (higher than 60° C.) at normal environment temperatures (20° C.) even for power dissipation in the object being as low as 500 mW. For comparison, skin burning caused by contact with hot objects starts at temperatures of around 65° C. The experiments have indicated that a power absorption of 500 mW or more in a typical foreign object rises its temperature to an unacceptable level.
In order to prevent such scenarios, it has been proposed to introduce foreign object detection where the power transmitter can detect the presence of a foreign object and reduce the transmit power. For example, the Qi system includes functionality for detecting a foreign object, and for reducing power if a foreign object is detected.
The power dissipation in a foreign object can be estimated from the difference between transmitted and received power. In order to prevent that too much power is dissipated in a foreign object, the transmitter can terminate the power transfer if the power loss exceeds a threshold.
In the current Qi Standard the preferred approach is to determine the power loss across the interface between the power transmitter and the power receiver in order to determine any loss in foreign objects. For this purpose, the power receiver estimates the amount of power that enters its interface surface—i.e. the received power. In order to generate the estimate, the power receiver measures the amount of power provided to the load, and adds an estimate of the losses in components—coil, resonant capacitor, rectifier, etc., as well as losses in conductive elements of the device, such as in metal parts that are not exposed to the user. The power receiver communicates the determined received power estimate to the power transmitter at regular intervals.
The power transmitter estimates the amount of power extracted from the power signal—i.e. the transmitted power. The power transmitter can then calculate the difference between the transmitted power and the received power, and if the difference exceeds a given level, the power transmitter may determine that a situation has occurred where an unacceptable power may be dissipated in a foreign object. For example, a foreign object may be positioned on or near the power transmitter resulting in this being heated due to the power signal. If the power loss exceeds a give threshold, the power transmitter terminates the power transfer in order to prevent the object from getting too hot. More details can be found in the Qi Standard, System Description Wireless power.
When performing this power loss detection, it is important that the power loss is determined with sufficient accuracy to ensure that the presence of a foreign object is detected. Firstly, it must be ensured that a foreign object which absorbs significant power from the magnetic field is detected. In order to ensure this, any error in estimating the power loss calculated from the transmitted and received power must be less than the acceptable level for power absorption in a foreign object. Similarly, in order to avoid false detections, the accuracy of the power loss calculation must be sufficiently accurate to not result in estimated power loss values that are too high when no foreign object is present.
It is substantially more difficult to determine the transmitted and received power estimates sufficiently accurately at higher power levels than for lower power levels. For example, assuming that an uncertainty of the estimates of the transmitted and received power is ±3%, this can lead to an error of ±150 mW at 5 W transmitted and received power, and ±1.5 W at 50 W transmitted and received power.
Thus, whereas such accuracy may be acceptable for a low power transfer operation it is not acceptable for a high power transfer operation.
Typically, it is required that the power transmitter must be able to detect power consumption of foreign objects of only 350 mW or even lower. This requires very accurate estimation of the received power and the transmitted power. This is particularly difficult at high power levels, and frequently it is difficult for power receivers to generate estimates that are sufficiently accurate. However, if the power receiver overestimates the received power, this can result in power consumption by foreign objects not being detected. Conversely, if the power receiver underestimates the received power, this may lead to false detections where the power transmitter terminates the power transfer despite no foreign objects being present.
In order to obtain the desired accuracy, it has been proposed that the power transmitter and power receiver are calibrated to each other before power transfer at least at higher levels is performed. However, although such an approach may be desirable in many scenarios, it may also be considered inconvenient to the user as such calibrations may at best delay the power transfer, and may in many scenarios require user involvement before power transfer can proceed.
An improved power transfer system would be advantageous. In particular, an approach that allows improved operation while maintaining a user friendly approach would be advantageous. Particularly, an approach that allows easier user operation while ensuring safe operation, especially at higher power levels, would be advantageous. An improved power transfer system allowing increased flexibility, facilitated implementation, facilitated operation, safer operation, reduced risk of foreign object heating, increased accuracy and/or improved performance would be advantageous. | {
"pile_set_name": "USPTO Backgrounds"
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A. E. Feiring, Journal of Fluorine Chemistry, 13, 7-18 (1979) discloses the use of tantalum pentafluoride as a catalyst for the addition of hydrogen fluoride to tetra- and trichloroethane and related compounds. The catalyst is also useful in fluorine-chlorine exchange reactions. However, under the conditions of the batch experiments [HF/CCl.sub.2 .dbd.CCl.sub.2 =2.5, temperature=150.degree. C., reaction time=six hours] catalysts such as BF.sub.3, TaCl.sub.5, Ta.sub.2 O.sub.5, CoF.sub.3, V.sub.2 O.sub.5, ZrCl.sub.4, NbCl.sub.5, HgO, and WCl.sub.6 showed no catalytic activity for the addition of HF to tetrachloroethylene.
The use of tantalum pentafluoride as a catalyst for the addition of hydrogen fluoride to unsaturated compounds has been disclosed and claimed by Feiring in U.S. Pat. No. 4,258,255.
The use of dehydrating agents to prepare anhydrous TaF.sub.5 has been disclosed and claimed in Kim U.S. Pat. No. 4,124,692.
The need to provide an economically attractive process to produce highly fluorinated, hydrogen-containing alkanes useful as alternatives to current products for refrigerants, blowing agents, etc. has sparked interest in this area.
This invention provides a low cost process for the preparation of fluorinated alkanes made by catalyzed HF addition to olefins and/or fluorine for chlorine exchange on chlorinated alkanes using a system comprised of Ta.sub.2 O.sub.5 or Nb.sub.2 O.sub.5, a dehydrating agent(s), e.g., HOSO.sub.2 Cl (chlorosulfonic acid), and SOCl.sub.2 (thionyl chloride) and excess HF. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a holder, and more particularly to a tool holder.
2. Description of the Prior Art
A typical tool holder is disclosed in U.S. Pat. No. 2,119,217 to Rocchi, filed Feb. 25, 1936. In Rocchi, the tools can not be stably held in place and may slide within the recesses; in addition, the tools are stably retained in place by a retaining member and can not be taken out before the retaining member is opened.
Another type of tool holder is disclosed in U.S. Pat. No. 2,541,597 to Midling, filed Dec. 22, 1947. In Midling, the tools can be easily unloaded in one upsweeping motion of the two hands; however, correspondingly, the tools will be easily disengaged from the tool holder when the tool holder is disposed up-side-down.
The present invention has arisen to mitigate and/or obviate the afore-described disadvantages of the conventional tool holders. | {
"pile_set_name": "USPTO Backgrounds"
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The present application is directed to electronic fabrication and more particularly fabrication of hybrid electronic platforms, which are comprised of different types of components such as integrated circuits and discrete components located on a common substrate. Hybrid electronic platforms employ cost-effective, large-area manufacturing techniques while keeping the same complex functionality and processing capability as silicon-based systems. Due to temperature and mechanical reasons, traditional silicon integration methods, such as solder bonding and wire bonding may not be suitable for hybrid platforms which may include flexible printed electronics. Various packaging techniques have been developed for chip integration on flexible substrates. For example, anisotropic conductive film (ACF) can be applied to bond and connect a chip to a circuit on a plastic substrate. However, a downside of this method is the limitation of the minimal size of the contact pads on the chip which can be bond with the adhesive.
It is considered useful to provide techniques and arrangements which overcome the noted limitations and others. | {
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1. Field of Invention
The invention relates to a method for pattern etching a substrate, and more particularly to a method for pattern etching a substrate while reducing the effects of micro-loading and feature roughness.
2. Description of Related Art
Typically, during fabrication of integrated circuits (ICs), semiconductor production equipment utilize a (dry) plasma etch process to remove or etch material along fine lines or within vias or contacts patterned on a semiconductor substrate. The success of the plasma etch process requires that the etch chemistry includes chemical reactants suitable for selectively etching one material while substantially not etching another material.
For example, on a semiconductor substrate, a pattern formed in a protective mask layer can be transferred to an underlying layer of a selected material utilizing a plasma etching process. The protective mask layer can comprise a radiation-sensitive layer, such as a photo-resist layer, having a pattern formed therein using a lithographic process.
In order to pattern finer features in the lithographic layer using conventional lithography techniques, multi-layer masks can be implemented. For example, the multi-layer mask may include a bilayer mask or trilayer mask including one or more soft mask layers, or one or more hard mask layers, or a combination thereof. With the inclusion of a second or third layer, the uppermost lithographic layer may be thinner than the thickness customarily chosen to withstand the subsequent dry etching process(es) and, therefore, using conventional lithography techniques, finer features may be formed in the thinner lithographic layer. Thereafter, the finer feature formed in the lithographic layer may be transferred to the underlying second or third layers using a dry development process, such as a dry etching process.
Once the pattern is established in the multi-layer mask, the pattern is transferred to the underlying layers using one or more etching processes. Examples of such an etching process include reactive ion etching (RIE), which is in essence an ion activated chemical etching process. However, although RIE has been in use for decades, its maturity is accompanied by several issues including, among other things, feature-shape loading effects (i.e., micro-loading) and critical dimension (CD) control. A loading effect is generally used to describe an etching process having an etch rate that depends upon the exposed area. Local variations in the pattern density of the pattern being transferred using the etching process can cause local variations in the etch rate due to local depletion of the reactive species and this effect is referred to as micro-loading. It is essential that the micro-loading effect is reduced in order to mitigate RIE lag. Moreover, as pattern feature dimensions become finer, RIE lag worsens.
Additionally, it is essential that a critical dimension (CD) for the mask layer is preserved during pattern transfer such that the CD bias is minimal, i.e., the CD bias is the difference between the initial CD for the pattern in the mask layer and the final CD for the pattern in the underlying layer(s). Further, if a CD bias is unavoidable, it is essential that the CD bias is uniformly maintained across the substrate. Further yet, if a CD bias is unavoidable, it is essential that the offset in CD bias between dense features (e.g., closely spaced features) and isolated features (e.g., widely spaced features) is minimal.
Furthermore, during pattern transfer, undulations or variations in the edge profile of the pattern in the mask layer as well as variations in pattern dimension, can be propagated in to the underlying layers. These undulations or variations may be observed as edge roughness or line edge roughness (LER) in some instances, or as pitting in other instances. Edge roughness may arise due to damage to the layer of radiation-sensitive material. During the application of the radiation-sensitive material, the post-application bake (PAB), the exposure step, the post-exposure bake (PEB), or the wet developing step, or any combination thereof, the radiation-sensitive material may be damaged. Moreover, damage may occur during the initial phases of the ARC layer etch, hard mask etch, or thin film etch. Pitting may arise when performing pattern transfer in a porous material, such as porous low dielectric constant (low-k) materials or porous ultra-low-k materials. | {
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1. Field of the Invention
The present invention relates to glass for a magnetic recording medium substrate that is suitable as a substrate material for magnetic recording media such as hard disks; a magnetic recording medium substrate employing the above glass and a method of manufacturing the same; a magnetic recording medium substrate blank usable for obtaining the above substrate; a magnetic recording medium equipped with the above substrate and a method of manufacturing the same; and a magnetic recording apparatus equipped with the above substrate.
2. Discussion of the Background
With the development of information-related infrastructure such as the Internet, the need for information recording media such as magnetic disks and optical disks has increased sharply. The main structural components of the magnetic memory devices of computers and the like are magnetic recording media and magnetic heads for magnetic recording and reproduction. Known magnetic recording media include flexible disks and hard disks. Of these, examples of the substrate materials employed in hard disks (magnetic disks) include aluminum substrates, glass substrates, ceramic substrates, and carbon substrates. In practical terms, depending on size and application, aluminum substrates and glass substrates are primarily employed. In the hard disk drives of laptop computers, along with higher density recording of magnetic recording media in addition to impact resistance, the requirement of increased surface smoothness of the disk substrate is intensifying. Thus, there are limits to how well aluminum substrates, with afford poor surface hardness and rigidity, can respond. Accordingly, the development of glass substrates is currently the mainstream (see, for example, Documents 1 to 10 and the following English language family members, which are expressly incorporated herein by reference in their entirety).
In recent years, with the goal of achieving even higher density recording in magnetic recording media, the use of magnetic materials of high magneto-anisotropic energy (magnetic materials of value), such as Fe—Pt and Co—Pt based materials, is being examined (see, for example, see Document 11 and the following English language family members, which are expressly incorporated herein by reference in their entirety). It is necessary to reduce the particle diameter of the magnetic particles to achieve higher density recording. However, when just the particle diameter is reduced, the deterioration of magnetic characteristics due to thermal fluctuation becomes a problem. Magnetic materials of high Ku value tend not to be affected by thermal fluctuation, and are thus expected to contribute to the achievement of greater recording density.
Document 1: Published Japanese Translation of a PCT international publication for patent application (TOKUHYO) No. Heisei 9-507206 or English language family member U.S. Pat. No. 5,958,812
Document 2: Japanese Unexamined Patent Publication (KOKAI) No. 2007-51064 or English language family member U.S. Pat. No. 5,900,296
Document 3: Japanese Unexamined Patent Publication (KOKAI) No. 2001-294441
Document 4: Japanese Unexamined Patent Publication (KOKAI) No. 2001-134925
Document 5: Japanese Unexamined Patent Publication (KOKAI) No. 2001-348246
Document 6: Japanese Unexamined Patent Publication (KOKAI) No. 2001-58843 or English language family member US2002/010066A1 and U.S. Pat. No. 6,949,485
Document 7: Japanese Unexamined Patent Publication (KOKAI) No. 2006-327935
Document 8: Japanese Unexamined Patent Publication (KOKAI) No. 2005-272212 or English language family members US 2005/215414A1 and U.S. Pat. No. 7,687,419
Document 9: Japanese Unexamined Patent Publication (KOKAI) No. 2004-43295 or English language family member US2003/220183A1, U.S. Pat. No. 7,309,671, US2008/053152A1, and U.S. Pat. No. 7,767,607
Document 10: Japanese Unexamined Patent Publication (KOKAI) No. 2005-314159 or English language family members US 2005/244656A1 and U.S. Pat. No. 7,595,273
Document 11: Japanese Unexamined Patent Publication (KOKAI) No. 2004-362746 or English language family members US 2004/229006A1 and U.S. Pat. No. 7,189,438 | {
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Overhead projectors for large audience presentations are well known in the prior art. Such systems typically utilize transparencies for carrying the information to be viewed by the audience.
With advances in modern liquid crystal technology, such transparencies have been replaced by full color liquid crystal display panels driven by video signal producing devices, such as personal computers. In this regard, the liquid crystal display panel is typically positioned on the stage of an overhead projector so the liquid crystal image may be projected for viewing purposes.
While the above described project system has been satisfactory for many applications, such a system is very bulky, heavy and awkward in size. Thus, such a system is not easily transportable by a business person who desires to travel from customer to customer for making sales presentations and the like.
Therefore, it would be highly desirable to have a new and improved liquid crystal projector that is compact in size and easily transportable.
Another problem with the use of an overhead projector in a business conference meeting, is that the projector generally has a very long optics path. In this regard, for example, the typical overhead projector includes a large, tall, upright housing with a raised projection lens in order to eliminate keystoning effects. Thus, such a projector unit does not have a low profile and is not very compact.
Therefore, it would be highly desirable to have a projector unit, which is compact in size and which does not produce images with undesirable substantial keystoning effects.
Other attempts have been made to develop compact overhead projectors by adapting their various parts to be foldable or collapsible. It would be highly desirable to have a new and improved compact projector, which has substantially no moving parts, is relatively inexpensive to manufacture and yet is small in size. In this regard, such a compact projector should have a very low profile to make it convenient to be transported. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a label producing apparatus for continuously producing RFID tag labels capable of reading or writing RFID tag communicating information from the outside through wireless communication.
2. Description of the Related Art
There are known RFID (Radio Frequency Identification) systems for reading and writing information between a compact RFID tag and a reader (reading device)/writer (writing device) in a non-contact manner. For example, a RFID circuit element, which is disposed to, for example, a label-shaped RFID tag, has an IC circuit part for storing predetermined RFID tag communicating information and an antenna connected to the IC circuit part for transmitting and receiving information. Accordingly, even if the RFID tag is soiled or disposed at an invisible position, the reader/writer can access the RFID tag communicating information of the IC circuit part (can read/write the information), and thus it is expected to use the RFID systems in various fields such as commodity management, inspection process, and the like.
There is known a writer (printer) disclosed in, for example, patent publication 1 as a writer (printer) for writing information to the RFID circuit element. In the conventional technology, a strip-shaped tag medium (base sheet), on which rectangular labels (RFID labels) are bonded at predetermined intervals, is fed out, and when the tag medium passes through a transport path, predetermined RFID tag communicating information created on a device side is transmitted to antennas of RFID circuit elements contained in the respective labels and sequentially written to IC circuit parts (IC chips) connected to the antennas. Thereafter, the labels are transported downstream in a transporting direction, and print information corresponding to the RFID tag communicating information written above is printed to the surface of the RFID labels by a printing device (thermal head), thereby RFID tag labels are completed. Patent Publication 1: JP,A, 2003-159838 (paragraph Nos. 0011 to 0039, FIG. 1 to FIG. 5)
In the arrangement of the conventional technology, it is contemplated to arrange a tag tape roll as a cartridge so that it can be detachably mounted on a cartridge holder portion on the device side and to replace a tag medium (tag tape) when it is exhausted together with the cartridge so that the tag medium as consumable goods can be easily and readily replenished.
In this case, to write information to the RFID circuit element of the tag medium in the cartridge, the device antenna must be disposed to a position relatively near to the cartridge. However, since the cartridge itself is frequently mounted on and dismounted from the cartridge holder portion, there is a possibility that the mounting/dismounting property of the cartridge and the layout of the cartridge holder portion may be restricted or disturbed depending on a position at which the device antenna is disposed. | {
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Erectile Dysfunction (ED) is a repeated inability to achieve or maintain a penile erection for sexual intercourse. It is estimated that about 30 million men in the United States and 150 million men worldwide experience chronic erectile dysfunction. Additionally, studies have shown that about half of the men between the ages of 40 and 70 have erectile dysfunction to some degree. The prevalence of erectile dysfunction is illustrated by the fact that Viagra, an ED drug manufactured by Pfizer, has been prescribed to more than 35 million men worldwide as of 2011.
The human penis consists of three erectile bodies: two corpora cavernosa chambers and one corpus spongiosum chamber. Together these three chambers make up the expandable erectile tissues along the length of the penis which fill with blood during penile erection. The two corpora cavernosa lie along the penis shaft, from the pubic bones to the head of the penis, where they join. These formations are made of a sponge-like tissue containing irregular blood-filled spaces lined by endothelium and separated by trabeculae of smooth muscle fibers with an extracellular matrix of which the main components are collagens, elastic fibers, proteoglycans/glycoseaminoglycans, in addition to numerous unmyelinated and preterminal autonomic nerves.
The importance of corporal cavernosal smooth muscle cells (SMCs) in potency is well-established. Normal smooth muscle content and function are necessary for the initiation and maintenance of erection. Additionally, elastin and collagen fibers are also important penile constituents. Collagen is a key structural protein in tissues subjecting to stretching forces. Collagen provides structural integrity that allows the cavernosum to withstand pressure increase during erection. Some researchers argue that without this rigid collagen network, the penis would maintain a flaccid form.
Erectile dysfunction can be caused by a number of factors, including physical, psychological, neurological, vascular and endocrinal issues. Reduced blood flow to the penis and nerve damage are the most common causes of erectile dysfunction. Underlying causes include, but are not limited to, vascular disease, diabetes, drugs, hormone imbalance, neurological causes, pelvic trauma in surgery, Peyronie's Disease and venous leak.
Currently, the most common method for treating erectile dysfunction is through oral inhibitors of phosphodiesterase V (PDE-5), including the medications: Sildenafil (Viagra®), Vardenafil (Lavetra®) and Tadalafil (Cialis®). However, numerous patients remain unresponsive to treatment, do not tolerate the adverse effects associated with the treatment, or are ineligible for treatment. Thus, there remains a need for a safe and effective treatment of erectile dysfunction which can be used without the side effects associated with the use of PDE-5 inhibitors. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a non-volatile semiconductor memory device (EEPROM) which is electrically rewritable, and particularly, which multi-value-stores more information than 1-bit information in one memory cell.
2. Description of the Related Art
As one of EEPROMs, a NAND cell type EEPROM which can be integrated at a high density is known. In a NAND cell, a plurality of memory cells are coupled in series with each other such that a source and a drain are shared by adjacent memory cells. One terminal of the NAND cell is coupled to a bit line. Each memory cell generally has a structure obtained by stacking a floating gate (charge storage layer) and a control gate. A memory cell array is integrally formed in a p-type substrate (or a p-type well formed in an n-type substrate). The drain of the NAND cell is coupled to the bit line through one selective transistor, and the source of the NAND cell is coupled to a common source line through the other selective transistor. The control gates of the memory cells are coupled to word lines continuously arranged in a row direction.
The operation of the NAND cell type EEPROM is as follows.
Data are sequentially written in the memory cells from the memory cell located at the position farthest from the bit line. A data write operation is performed such that a high potential Vpp (=about 20 V) is applied to the control gate of a selected memory cell, an intermediate potential Vppm (=about 10 V) is applied the control gate and selective gate of a memory cell closer to the bit line than the selected memory cell, and 0 V or an intermediate potential Vm (=about 8 V) is applied to the bit line in accordance with data to be written in the memory cells.
More specifically, when 0 V is applied to the bit line, this potential is transferred to the drain of the selected memory cell, and electrons are injected from the drain to the charge storage layer. In this manner, the threshold voltage of the selected memory cell is shifted from an initial negative value in a positive direction. This state is represented by, e.g., `1`. When the intermediate potential Vm is applied to the bit line, electron injection does not effectively occur. For this reason, the threshold voltage does not change, and the threshold voltage is kept negative. This state is represented by `0`. The data write operation is simultaneously performed for memory cells which share a control gate.
A data erasing operation is simultaneously performed for all the memory cells in the NAND cell.
More specifically, all the control gates are set at 0 V, and a p-type well is set at 20 V. At this time, the selective gates, the bit line, and the source line are set at 20 V. Therefore, electrons of the charge storage layer are discharged into the p-type well, the threshold voltage is shifted in a negative direction, and the states of all the memory cells are set at `0`.
A data read operation is performed such that the control gate of a selected memory cell is set at 0 V, the control gates and selective gates of the remaining memory cells are set at a power supply potential Vcc (to be referred to as only Vcc hereinafter), and it is checked whether a current flows in the selected memory cell (state `0`) or not (state `1`).
Due to the limitation of the read operation, the threshold voltage after `1` has been written must be controlled to fall within a range of 0 V to Vcc. For this purpose, a write verify operation is performed, a memory cell set in an insufficient `1` write state is detected, and rewrite data is set such that a rewrite operation is performed for only the memory cell set in the insufficient `1` write state (bit-by-bit verify). The memory cell set in the insufficient `1` write state is detected by performing a read operation (verify read operation) while the selected control gate is set at, e.g., 0.5 V (verify potential).
In this case, the threshold voltage of the memory cell has a margin with respect to 0 V. For this reason, if the potential of the control gate is less than 0.5 V, a current flows in the selected memory cell, and the memory cell is detected as a memory cell set in an insufficient `1` write state. A current flows in a memory cell set in a `0` write state. For this reason, a circuit called a verify circuit for compensating for the current flowing in the memory cell is arranged to prevent the memory cell from being erroneously defined as a memory cell having the sufficient `1` write state. This verify circuit performs a write verify operation at a high speed.
As described above, when the data write operation is performed while the write operation and the write verify operation are repeated, a time for writing data in each memory cell is optimized, and the threshold voltage after `1` has been written is controlled to fall within a range of 0 V to Vcc.
In the NAND cell type EEPROM, a so-called multi-value storing cell in which states after the write operation are represented by n data, i.e., data `0`, `1`, `2`, . . . , and `n` is proposed. In a ternary storing cell (n=3), three states after the write operation are defined as follows. For example, a threshold voltage is negative in a `0` write state, a threshold voltage is 0 V to Vcc/2 in a `1` write state, and a threshold voltage is Vcc/2 to Vcc in a `2` write state.
FIG. 1 shows an arrangement of a ternary storing NAND cell type EEPROM proposed by the present inventors in corresponding U.S. application Ser. No. 08/308,534.
A ternary storing NAND cell type EEPROM has a bit line control circuit 2 for controlling the bit lines of memory cell arrays 1a and 1b in a read/write operation, and a word line driving circuit 6 for controlling the word line potentials of the memory cell arrays 1a and 1b.
The bit line control circuit 2 selects a predetermined bit line on the basis of a column decoder 3. The bit line control circuit 2 transmits and receives write/read data to/from an input/output data converting circuit 4 through a data input/output line (I/O line).
The input/output data converting circuit 4 converts the multi-value information read out from the memory cell into binary information to externally output the multi-value information, and converts the binary information of externally input write data into the multi-value information of the memory cell. The input/output data converting circuit 4 is coupled to a data input/output buffer 5 for controlling an input/output operation between the data input/output buffer 5 and an external circuit.
FIG. 2 shows the memory cell arrays 1a and 1b of the NAND cell type EEPROM in FIG. 1 and a related art's bit line control circuit 2. One terminal of a NAND cell is coupled to a bit line BLa, and the other terminal is coupled to a common source line Vsa. One terminal of another NAND cell is coupled to a bit line BLb, and the other terminal is coupled to a common source line Vsb. Selective gates SG1a, SG2a, SG1b, and SG2b and control gates CG1a to CG8a and CG1b to CG8b are shared by a plurality of NAND cells, and memory cells M which share one control gate constitute a page.
Each memory cell stores data on the basis of a threshold voltage Vt of the corresponding memory cell, and stores data `0`, `1`, and `2`. Since one memory cell has three states, nine combinations can be obtained by two memory cells. Eight combinations of the nine combinations are used to store 3-bit data in two memory cells. In this example, a pair of adjacent two memory cells which share a control gate store 3-bit data. The memory cell arrays 1a and 1b are formed on a dedicated p-type well.
A flip-flop FF1 constituted by n-channel MOS transistors Qn8 to Qn10 and p-channel MOS transistors Qp3 to Qp5 and a flip-flop FF2 constituted by n-channel MOS transistors Qn11 to Qn13 and p-channel MOS transistors Qp6 to Qp8 latch write/read data. The flip-flops FF1 and FF2 also operate as sense amplifiers. The flip-flop FF1 latches write data information indicating that "`0` is written or one of `1` and `2` is written`, and the flip-flop FF1 latches read data information indicating that the memory cell `holds information of `0` or holds one of information of `1` and information of `2`". The flip-flop FF2 latches write data information indicating that "`1` is written or `2` is written`". The flip-flop FF2 latches read data information indicating that a memory cell `holds information of `2` or holds one of information of `0` and information of `1`".
When a precharge signal .phi. pa goes `H`, an n-channel MOS transistor Qn1 transfers a potential Va to the bit line BLa. When a precharge signal .phi. pb goes `H`, an n-channel MOS transistor Qn20 transfers a potential Vb to the bit line BLb. N-channel MOS transistors Qn4 to Qn7 and p-channel MOS transistors Qp1 and Qp2 selectively transfer potentials VBHa, VBMa, and VBLa to the bit line BLa in accordance with the data latched in the flip-flops FF1 and FF2. N-channel MOS transistors Qn14 to Qn17 and p-channel MOS transistors Qp9 and Qp10 selectively transfer potentials VBHb, VBMb, and VBLb to the bit line BLb in accordance with the data latched in the flip-flops FF1 and FF2.
When a signal .phi. a1 goes `H`, an n-channel MOS transistor Qn2 couples the flip-flop FF1 to the bit line BLa. When a signal .phi. a2 goes `H`, an n-channel MOS transistor Qn3 couples the flip-flop FF2 to the bit line BLa. When a signal .phi. b1 goes `H`, an n-channel MOS transistor Qn19 couples the flip-flop FF1 to the bit line BLb. When a signal .phi. b2 goes `H`, an n-channel MOS transistor Qn18 couples the flip-flop FF2 to the bit line BLb.
The operation of the EEPROM arranged as described above will be described below with reference to FIGS. 3 to 5. FIG. 3 shows read operation timings, FIG. 4 shows write operation timings, and FIG. 5 shows verify read operation timings. In the following description, a case wherein a control gate CG2 is selected is exemplified.
A read operation will be described below with reference to FIG. 3. The read operation is performed in two basic cycles.
In the first read cycle, when the potential is set at 3 V, the bit line BLb serving as a reference bit line is precharged. When the precharge signal .phi. pa goes `L`, the selective bit line BLa floats, and the common source line Vsa is set at 6 V. The selective gates SG1a and SG2a and control gates CG1a and CG3a to CG8a are set at 6 V. At the same time, the selected control gate CG2a is set at 2 V. The bit line BLa is charged to a predetermined potential in accordance with the data of the selected memory cell.
When flip-flop activating signals .phi. n1 and .phi. p1 go `L` and `H`, respectively, the flip-flop FF1 is reset. When the signals .phi. a1 and .phi. b1 go `H`, the flip-flop FF1 is coupled to the bit lines BLa and BLb. When the signals .phi. n1 and .phi. p1 go `H` and `L`, respectively, the potential of the bit line BLa is sensed with reference to the potential of the reference bit line BLb, and the flip-flop FF1 latches information indicating `data `0` or one of data `1` and data `2`".
In the second read cycle, unlike in the first read cycle, the potential of the reference bit line BLb is not 3 V but 1 V, and signals .phi. a2, .phi. b2, .phi. n2, and .phi. p2 are output in place of the signals .phi. a1, .phi. b1, .phi. n1, and .phi. p1 to operate the flip-flop FF2. Therefore, in the second read cycle, information indicating `data `2` or one of data `1` or data `0`" is latched in the flip-flop FF2.
With the two read cycles, data written in the memory cell is read out.
Data in the memory cell is erased prior to a data write operation, and a threshold voltage Vt of the memory cell is -1.5 V or less. An erasing operation is performed such that the p-type well, the common source line Vsa, the selective gates SG1a and SG2a are set at 20 V, and the control gates CG1a to CG8a are set at 0 V.
A write operation will be described below with reference to FIG. 4.
Write data data1 and data2 are latched in the flip-flops FF1 and FF2, respectively. The data data1 is data for controlling "`0` write operation or one of `1` write operation and `2` write operation`". A node N1 is at `n` in the `0` write operation, and the node N1 is at `H` in one of the `1` write operation and the `2` write operation. The data data2 is data for controlling "`1` operation or `2` write operation`". A node N3 is at `L` in the `1` write operation, and the node N2 is at `H` in the `2` write operation.
When the precharge signal .phi. pa goes `L`, the bit line BLa floats. The selective gate SG1a is set at Vcc, and the control gates CG1a to CG8a are set at Vcc. The selective gate SG2a is at 0 V in the write operation. At the same time, a signal VRFYa goes `H`, and a signal PBa goes `L`. In the `0` write operation, since data set at `L` is latched in the node N1 of the flip-flop FF1, the bit line BLa is charged to Vcc with the potential VBHa. In one of the `1` write operation and the `2` write operation, the bit line BLa floats.
The selective gate SG1a and the control gates CG1a to CG8a are set at 10 V, the potential VBHa and a potential Vrw are set at 8 V, and a potential VBMa is set at 1 V. At this time, when the `0` write operation is to be performed, the bit line BLa is charged to 8 V. In the `1` write operation, data is latched such that the node N3 of the flip-flop FF2 is set at `L`. For this reason, 1 V is applied to the bit line BLa by the potential VBMa. In the `2` write operation, the bit line BLa is set at 0 V by the potential VBLa. Thereafter, the selected control gate CG2a is set at 20 V.
In one of the `1` write operation and the `2` write operation, electrons are injected into the charge storage layer of the memory cell due to the potential difference between the bit line BLa and the control gate CG2a, thereby increasing the threshold voltage of the memory cell. In the `1` write operation, an amount of charge to be injected into the charge storage layer of the memory cell must be smaller than that of the `2` write operation. For this reason, the bit line BLa is set at 1 V to moderate the potential difference between the bit line BLa and the control gate CG2a to 19 V. In the `0` write operation, electron injection is suppressed by a bit line potential (=8 V), and the threshold voltage of the memory cell does not change. Upon completion of the write operation, the selective gate SG1a and the control gates CG1a to CG8a are set at 0 V, and the potential (=8 V) of the bit line BLa at the `0` write operation is reset to 0 V. When this order is reversed, the state of the `2` write operation is temporarily set, and erroneous data is written in the `0` write operation.
After the write operation, the write state of the memory cell is checked, and a verify read operation is performed to perform an additional write operation for a memory cell set in an insufficient write state. The verify read operation will be described below with reference to FIG. 5.
The verify read operation is similar to the first read cycle except that the data of the flip-flop FF1 is reversed, the potential Vb is set at Vcc, signals VRFYa and VRFYb are output, and, at this time, the potentials VBLb and VBMb are set at 2.5 V and 0.5 V, respectively. The potential of the reference bit line BLb is determined by the potentials Vb, VBLb, and VBMb and the data of the flip-flops FF1 and FF2. The signals VRFYa and VRFYb are output before the signal .phi. n1 and .phi. p1 go `L` and `H` respectively, after the selective gates SG1a and SG2a and the control gates CG1a to CG8a are reset to 0 V. More specifically, the signals VRFYa and VRFYb are determined after the potential of the bit line BLa is determined by the threshold voltage of a memory cell and before the flip-flop FF1 is reset.
The data reverse operation of the flip-flop FF1 will be described below.
When the potential Vb is set at 2.5 V, the bit line BLb serving as a reference bit line is precharged. When the precharge signals .phi. pa and .phi. pb go `L`, the bit lines BLa and BLb float. Subsequently, when the signal PBa goes `L`, the bit line BLa is charged with 2.5 V or more only when the node N1 is at `L. Thereafter, when the flip-flop activating signals .phi. n1 and .phi. p1 go `L` and `H`, respectively, the flip-flop FF1 is reset. When the signals .phi. a1 and .phi. b1 go `H`, the flip-flop FF1 is coupled to the bit lines BLa and BLb. When the signals .phi. n1 and .phi. p1 go `H` and `L`, respectively, the bit line potential is sensed.
With the above operation, the data of the flip-flop FF1 is reversed. At this time, in the flip-flops FF1 and FF2, the node N1 is set at `H` in a `0` write operation after the data reverse operation is performed, the node N1 is set at `L` at one of a `2` write operation and a `1` write operation after the data reverse operation is performed, and the node N3 is set at `H` in the `1` write operation and set at `L` in the `2` write operation.
In the verify read operation after `0` has been written, the node N1 is at `H`, and the n-channel MOS transistor Qn5 is in an ON state. For this reason, the signal VRFYa goes `H` independently of the state of a memory cell, and the bit line BLa is set at `L` by the potentials VBLa and VBMa which are at 0 V. Therefore, the bit line BLa is sensed by the flip-flop FF1 such that the node N1 is set at `L`, and rewrite data `0` is latched.
In the verify read operation after `1` has been written, the nodes N2 and N4 are at `H`. For this reason, when the signal VRFYb goes `H`, the reference bit line BLb is set at 2.5 V. Therefore, when the memory cell does not reach a `1` write state, the bit line BLa is at 2.5 V or more, and the bit line BLa is sensed by the flip-flop FF1 such that the node N1 is set at `H`, and rewrite data `1` is latched. When the memory cell reaches the `1` write state, the bit line BLa is at 2.5 V or less, and the bit line BLa is sensed by the flip-flop FF1 such that the node N1 is set at `L`. Rewrite data `0` is latched, and a threshold voltage does not change in the rewrite operation.
In the verify read operation after `2` has been written, the nodes N2 and N3 are set at `H`. For this reason, when the signal VRFYb goes `H`, the reference bit line BLb is set at 0.5 V. Therefore, when the memory cell does not reach a `2` write state, the bit line BLa is at 0.5 V or more, and the bit line BLa is sensed by the flip-flop FF1 such that the node N1 is set at `H`. Rewrite data `2` is latched. When the memory cell reaches the `2` write state, the bit line BLa is at 0.5 V or less, and the bit line BLa is sensed by the flip-flop FF1 such that the node N1 is set at `L`. Rewrite data `0` is latched, and the threshold voltage does not change in the rewrite operation.
With this verify read operation, rewrite data is set as shown in Table 1 on the basis of write data and the write state of the memory cell.
TABLE 1 ______________________________________ WRITE DATA 00011222 DATA OF MEMORY CELL 01201012 REWRITE DATA 00010220 ______________________________________
As is apparent from Table 1, a `1` write operation is performed for only a memory cell which is to be set in a `1` write state but is set in an insufficient `1` write state, and a `2` write operation is performed for only a memory cell which is to be set in a `2` write state but is set in an insufficient `2` write state.
When the write operation and the verify read operation are repeated, a data write operation is performed for each memory cell such that a write time is optimized.
Table 2 shows the potentials of the portions of a memory cell array in an erasing operation, a write operation, a read operation, and a verify read operation.
TABLE 2 __________________________________________________________________________ WRITE ERASING OPERATION READ VERIFY READ OPERATION "0" "1" "2" OPERATION OPERATION __________________________________________________________________________ BL 20 V 8 V 1 V 0 V SEE FIG. 5 SG1 20 V 10 V 6 V 6 V CG1 20 V 10 V 6 V 6 V CG2 0 V 20 V 2 V 2 V CG3 0 V 10 V 6 V 6 V CG4 0 V 10 V 6 V 6 V CG5 0 V 10 V 6 V 6 V CG6 0 V 10 V 6 V 6 V CG7 0 V 10 V 6 V 6 V CG8 0 V 10 V 6 V 6 V SG2 20 V 0 V 6 V 6 V VS 20 V 0 V 6 V 6 V p-well 20 V 0 V 0 V 0 V __________________________________________________________________________
As described above, when the bit line control circuit shown in FIG. 2 is used, a data write operation, a data verify read operation, a data read operation, and a data erasing operation can be performed for the memory cells of a ternary storing EEPROM.
However, the read operation requires two basic cycles, i.e., a first read cycle for determining "`0` or one of `1` and `2`" and a second read cycle for determining "`2` or one of `1` and `0`". The verify read operation also requires two basic cycles, i.e., a reverse cycle and a verify cycle. Therefore, each operation requires a long time.
As described above, in the ternary (multi-value) EEPROM having the bit line control circuit shown in FIG. 2, the read operation requires the two basic cycles, i.e., the first read cycle and the second read cycle, and the verify read operation requires the two basic cycles, i.e., the reverse cycle and the verify cycle. Therefore, each operation requires a long time. | {
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The present invention generally relates to electrical lighting systems. More particularly, the present invention relates to systems and methods for maintaining the lighting systems and for monitoring energy consumption of the lighting systems.
Energy consumption in the United States has grown in alarming proportions. One concern is that indiscriminate use of energy and other resources will leave the environment and those that live in it wanting. That concern has existed at least since the oil crisis of the 1970""s, and since then American consumers and businesses have focused their attention to the current usage and future supply of energy. The government increased its demand for energy efficient systems when, in the late 1980""s and early 1990""s, the Department of Energy and the Public Utility Commission provided a financial incentive for utilities to offer Demand Side Measures (DSM) to their customers. End customers took advantage of DSM in the form of utility funded rebates used to purchase more energy efficient motors, variable frequency drives, lighting systems, and occupancy sensors. Despite the prevalence of DSM programs offered by local utilities, however, not all building managers were aware of the programs, and a small percentage of all buildings participated.
To encourage the nation""s top corporations to upgrade their facility floor space to more energy efficient lighting, the United States Environmental Protection Agency launched the Green Lights initiative in 1991. Even with the Green Lights initiative, by the end of 1996 only a small percentage of pledged space for lighting retrofit had been upgraded with new lighting technologies. Further initiatives include the Energy Policy Act (EPACT 1992), the President""s Climate Change Initiative (1993) and an Executive Order on Energy Efficiency in Federal Facilities by the year 2005. Increased market demand for energy efficient lighting products has also been stimulated by performance based contracting programs offered by energy service companies.
Accordingly, there is a need for improved facility lighting systems. The method and systems should provide an incentive for facility owners to use the improved lighting systems. Thus, the method and system of the preferred embodiments may provide for energy monitoring and maintenance of lighting systems at reduced costs to the facility owner.
The present invention is defined by the following claims, and nothing in this section should be taken as a limitation on those claims. By way of introduction, the preferred embodiment described below includes a method and system for servicing, monitoring and maintaining lighting systems.
A first aspect is described for charging a fee to an end user where a service company upgrades and services a lighting system of the end user""s facility. To determine the fee, an original power consumption of the facility is determined before the lighting system is retrofitted with at least one power savings device. Thereafter, the lighting system is retrofitted with the at least one power saving device. Then, a new power consumption value is measured. Finally, the fee is charged to the end user, such that the fee is a function of a difference between the original power consumption and the new power consumption.
A second aspect is described for monitoring energy consumption of a lighting system. Power consumption of the lighting system is controlled with a lighting control unit connected with the lighting system. The lighting control unit collects power consumption data and transfers the power consumption data via a data transfer line to a control center. The power consumption data is received at a server located at the control center. The received power consumption data may then be used to calculate the fee charged to the customer.
A third aspect is described for maintaining a lighting system which includes lighting circuitry. At least one monitor monitors the lighting circuitry of at least one customer and produces at least one alarm signal as a function of the occurrence of a system fault. A data transfer line transfers the alarm signal to a control center. A server receives the alarm signal at the control center, and at least one operator coordinates service to the lighting circuitry when the alarm signal indicates that a fault exists with the lighting system. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates generally to heating, ventilation, and air conditioning (HVAC) systems and more particularly to computer-controlled air vents.
In residential HVAC systems it is not customary to install a HVAC control thermostat in each individual room of a house, and therefore it is difficult to maintain a uniform temperature environment in all rooms. Typically, the only room having a controlled temperature environment is the room in which the control thermostat is located. Frequently, a system using a single control thermostat results in xe2x80x9ccoldxe2x80x9d rooms or xe2x80x9chotxe2x80x9d rooms in other parts of the building, due to exposure, location, heating duct configuration, and other causes. In order to heat a xe2x80x9ccoldxe2x80x9d room, the single control thermostat is typically set at a higher level, but this increases the temperature in the other rooms that are normally at a higher level. In order to cool a xe2x80x9chotxe2x80x9d room, the single control thermostat is typically set a lower level, but this decreases the temperature in the other rooms that are normally at a lower level. As a means of compensating for these temperature differentials, the standard air vents in each room are equipped with manual mechanical louver arrangements which will control the flow of air from 0% to 100%. However, any manual adjustments made to the air vents are static once made. Thus, although a register in a xe2x80x9chotxe2x80x9d room could be manually adjusted to restrict the flow of air passing through it, this adjustment could result in the same room becoming a xe2x80x9ccoldxe2x80x9d space unless the vent is later manually adjusted to the open position.
A particular problem faced by conventional HVAC systems is that the individual rooms of a building have different volumes, and thus are heated or cooled at different rates. For example, in a system having a small room and a large room, the small room will heat and cool more quickly than the large room. When the central thermostat is adjusted to a target temperature, the smaller room typically achieves the target temperature before the larger room, but because the manual air vents remain open, warm or cool air that could be used to heat or cool the larger room continues to pour into the small room, thereby wasting energy and causing overheating or overcooling. Consequently, the smaller room feels stifling or frigid.
An inherent problem with conventional HVAC systems is that they do not provide the proper amount of heating and cooling to all rooms proportionately. Additionally, such systems do not account for the changing variables that affect the thermal management needs of each room. These variables include people and equipment changes, external sun or snow loading, rain, daytime vs. nighttime needs, weekend vs. weekday needs, etc. It is possible to accommodate these changes manually by repeatedly opening and closing the air vents throughout the day, but such procedures are too time-consuming and labor-intensive to be practical or cost-effective. Consequently, uneven heating and cooling of the facility results, with smaller rooms heating or cooling faster (and to a greater degree) than larger rooms. As a result, more energy is consumed than is needed to maintain a comfortable environment.
The shortcomings of residential HVAC systems are more acute in commercial settings, where the cost of heating or cooling small to large buildings significantly impacts the profit margins of the business enterprises that occupy these buildings. The problem is somewhat alleviated in large commercial buildings, which are built to include elaborate cost-saving lighting, heating and cooling control systems that offer significant energy savings. Such systems typically include multiple HVAC zones, with each zone covering one or more workspaces within the building. In smaller business settings most heating and ventilation systems employ a single zone HVAC unit to supply conditioned, heated or cooled air to more than one distinct zone or room. However, in both large and small buildings, each room or zone may have different comfort requirements due to occupancy differences, individual preferences, and exterior heat and cooling load differences. The smaller business types of systems are referred to as single zone HVAC units because they are controlled from one centrally located OFF/ON thermostat controller. In a building having multiple zones that have different heating and cooling requirements, there is often no one, good representative location for the installation of a thermostat controller.
As in residential houses, smaller workspaces in commercial buildings tend to heat and cool faster than larger workspaces. This problem is exacerbated because commercial air vents typically do not include manual adjustment means. Additionally, the air vents found in commercial buildings are often located in the ceilings, which, unlike the ceilings in residential houses, may be approximately 8 feet or more above the floor. Consequently, individuals are often not able to adjust the airflow within their personal workspaces. In cases where manual adjustment means are provided, adjusting the air vents typically necessitates standing on a chair, desk, or ladder, which is inefficient and potentially hazardous.
The prior art provides a number of noteworthy attempts to create systems which address the problems of controlling the diverse needs of single and multi-zoned HVAC systems. Some of these systems describe remote controllers for starting and stopping an HVAC apparatus. Other systems describe wax motors and bi-metallic elements that close louvers disposed within an air register as the temperature of a room increases, and that open the louvers as the temperature of the room decreases. Further systems describe motors connected to louvers for opening and closing the louvers in response to control signals received from a centrally mounted controller. Still other systems describe variable air valve (VAV) units installed within the ducts of a HVAC system and hard-wired to a central remote controller. Yet other systems describe wireless remote thermostats that take over the temperature sensing and control functions of a central thermostat. However, the above systems are disadvantageous on a number of levels.
Firstly, the motorized air registers tend to be mechanically complex and difficult to install. Additionally, the air registers tend not to be computer-controlled. Furthermore, the motors are typically hard wired to a power source. Secondly, the remote control units tend to control the HVAC unit itself and not the individual air registers. Thirdly, the bi-metallic elements tend to open the air louvers as a room cools, thereby resulting in overcooling. Fourthly, where remote controllers are used to start and stop an HVAC unit, uneven cooling results throughout each HVAC zone because the registers within each zone are often manually controlled.
A computer-controlled air vent and methods of using the same are disclosed. In one embodiment, the computer-controlled air vent includes: a top plate; a base connected to the top plate; a component housing connected to the top plate and to the base; a plurality of louvers rotatably positioned within the base; a force-generating means connected to the louvers to rotate them between an open position and a closed position; a temperature sensor to sense an air temperature; a computer processor; a memory; a wireless transceiver; a bus to connect the processor, the wireless transceiver, and the memory; and a remote control device to control the opening and closing of the louvers. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field
The present invention relates to the field of routing phone calls and other telecommunications in a contact center system.
2. Related Art
The typical contact center consists of a number of human agents, with each assigned to a telecommunication device, such as a phone or a computer for conducting email or Internet chat sessions, that is connected to a central switch. Using these devices, the agents are generally used to provide sales, customer service, or technical support to the customers or prospective customers of a contact center or a contact center's clients.
Typically, a contact center or client will advertise to its customers, prospective customers, or other third parties a number of different contact numbers or addresses for a particular service, such as for billing questions or for technical support. The customers, prospective customers, or third parties seeking a particular service will then use this contact information, and the incoming caller will be routed at one or more routing points to a human agent at a contact center who can provide the appropriate service. Contact centers that respond to such incoming contacts are typically referred to as “inbound contact centers.”
Similarly, a contact center can make outgoing contacts to current or prospective customers or third parties. Such contacts may be made to encourage sales of a product, provide technical support or billing information, survey consumer preferences, or to assist in collecting debts. Contact centers that make such outgoing contacts are referred to as “outbound contact centers.”
In both inbound contact centers and outbound contact centers, the individuals (such as customers, prospective customers, survey participants, or other third parties) that interact with contact center agents using a telecommunication device are referred to in this application as a “caller.” The individuals acquired by the contact center to interact with callers are referred to in this application as an “agent.”
Conventionally, a contact center operation includes a switch system that connects callers to agents. In an inbound contact center, these switches route incoming callers to a particular agent in a contact center, or, if multiple contact centers are deployed, to a particular contact center for further routing. In an outbound contact center employing telephone devices, dialers are typically employed in addition to a switch system. The dialer is used to automatically dial a phone number from a list of phone numbers, and to determine whether a live caller has been reached from the phone number called (as opposed to obtaining no answer, a busy signal, an error message, or an answering machine). When the dialer obtains a live caller, the switch system routes the caller to a particular agent in the contact center.
Routing technologies have accordingly been developed to optimize the caller experience. For example, U.S. Pat. No. 7,236,584 describes a telephone system for equalizing caller waiting times across multiple telephone switches, regardless of the general variations in performance that may exist among those switches. Contact routing in an inbound contact center, however, is a process that is generally structured to connect callers to agents that have been idle for the longest period of time. In the case of an inbound caller where only one agent may be available, that agent is generally selected for the caller without further analysis. In another example, if there are eight agents at a contact center, and seven are occupied with contacts, the switch will generally route the inbound caller to the one agent that is available. If all eight agents are occupied with contacts, the switch will typically put the contact on hold and then route it to the next agent that becomes available. More generally, the contact center will set up a queue of incoming callers and preferentially route the longest-waiting callers to the agents that become available over time. Such a pattern of routing contacts to either the first available agent or the longest-waiting agent is referred to as “round-robin” contact routing. In round robin contact routing, eventual matches and connections between a caller and an agent are essentially random.
Some attempts have been made to improve upon these standard yet essentially random processes for connecting a caller to an agent. For example, U.S. Pat. No. 7,209,549 describes a telephone routing system wherein an incoming caller's language preference is collected and used to route their telephone call to a particular contact center or agent that can provide service in that language. In this manner, language preference is the primary driver of matching and connecting a caller to an agent, although once such a preference has been made, callers are almost always routed in “round-robin” fashion. Other attempts have been made to alter the general round-robin system. For example, U.S. Pat. No. 7,231,032 describes a telephone system wherein the agents themselves each create personal routing rules for incoming callers, allowing each agent to customize the types of callers that are routed to them. These rules can include a list of particular callers the agent wants routed to them, such as callers that the agent has interacted with before. This system, however, is skewed towards the agent's preference and does not take into account the relative capabilities of the agents nor the individual characteristics of the callers and the agents themselves. | {
"pile_set_name": "USPTO Backgrounds"
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It is desirable in communications to have the ability to estimate and adjust for phase error or phase noise, at least in part. | {
"pile_set_name": "USPTO Backgrounds"
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The invention relates to an improved model of speech or acoustic signals and methods for estimating the improved model parameters and synthesizing signals from these parameters.
Speech models together with speech analysis and synthesis methods are widely used in applications such as telecommunications, speech recognition, speaker identification, and speech synthesis. Vocoders are a class of speech analysis/synthesis systems based on an underlying model of speech. Vocoders have been extensively used in practice. Examples of vocoders include linear prediction vocoders, homomorphic vocoders, channel vocoders, sinusoidal transform coders (STC), multiband excitation (MBE) vocoders, improved multiband excitation (IMBE™), and advanced multiband excitation vocoders (AMBE™).
Vocoders typically model speech over a short interval of time as the response of a system excited by some form of excitation. Typically, an input signal s0(n) is obtained by sampling an analog input signal. For applications such as speech coding or speech recognition, the sampling rate ranges typically between 6 kHz and 16 kHz. The method works well for any sampling rate with corresponding changes in the associated parameters. To focus on a short interval centered at time t, the input signal s0(n) is typically multiplied by a window w(t,n) centered at time t to obtain a windowed signal s(t,n). The window used is typically a Hamming window or Kaiser window and can be constant as a function of t so that w(t,n)=w0(n−t) or can have characteristics which change as a function of t. The length of the window w(t,n) typically ranges between 5 ms and 40 ms. The windowed signal s(t,n) is typically computed at center times of t0, t1, . . . tm, tm+1, . . . . Typically, the interval between consecutive center times tm+1−tm approximates the effective length of the window w(t,n) used for these center times. The windowed signal s(t,n) for a particular center time is often referred to as a segment or frame of the input signal.
For each segment of the input signal, system parameters and excitation parameters are determined. The system parameters typically consist of the spectral envelope or the impulse response of the system. The excitation parameters typically consist of a fundamental frequency (or pitch period) and a voiced/unvoiced (V/UV) parameter which indicates whether the input signal has pitch (or indicates the degree to which the input signal has pitch). For vocoders such as MBE, IMBE, and AMBE, the input signal is divided into frequency bands and the excitation parameters may also include a V/UV decision for each frequency band. High quality speech reproduction may be provided using a high quality speech model, an accurate estimation of the speech model parameters, and high quality synthesis methods.
When the voiced/unvoiced information consists of a single voiced/unvoiced decision for the entire frequency band, the synthesized speech tends to have a “buzzy” quality especially noticeable in regions of speech which contain mixed voicing or in voiced regions of noisy speech. A number of mixed excitation models have been proposed as potential solutions to the problem of “buzziness” in vocoders. In these models, periodic and noise-like excitations which have either time-invariant or time-varying spectral shapes are mixed.
In excitation models having time-invariant spectral shapes, the excitation signal consists of the sum of a periodic source and a noise source with fixed spectral envelopes. The mixture ratio controls the relative amplitudes of the periodic and noise sources. Examples of such models are described by Itakura and Saito, “Analysis Synthesis Telephony Based upon the Maximum Likelihood Method,” Reports of 6th Int. Cong. Acoust., Tokyo, Japan, Paper C-5-5, pp. C17-20, 1968; and Kwon and Goldberg, “An Enhanced LPC Vocoder with No Voiced/Unvoiced Switch,” IEEE Trans. on Acoust., Speech, and Signal Processing, vol. ASSP-32, no. 4, pp. 851-858, August 1984. In these excitation models, a white noise source is added to a white periodic source. The mixture ratio between these sources is estimated from the height of the peak of the autocorrelation of the LPC residual.
In excitation models having time-varying spectral shapes, the excitation signal consists of the sum of a periodic source and a noise source with time varying spectral envelope shapes. Examples of such models are decribed by Fujimara, “An Approximation to Voice Aperiodicity,” IEEE Trans. Audio and Electroacoust., pp. 68-72, March 1968; Makhoul et al, “A Mixed-Source Excitation Model for Speech Compression and Synthesis,” IEEE Int. Conf. on Acoust. Sp. & Sig. Proc., April 1978, pp. 163-166; Kwon and Goldberg, “An Enhanced LPC Vocoder with No Voiced/Unvoiced Switch,” IEEE Trans. on Acoust., Speech, and Signal Processing, vol. ASSP-32, no. 4, pp. 851-858, August 1984; and Griffin and Lim, “Multiband Excitation Vocoder,” IEEE Trans. Acoust., Speech, Signal Processing, vol. ASSP-36, pp. 1223-1235, August 1988.
In the excitation model proposed by Fujimara, the excitation spectrum is divided into three fixed frequency bands. A separate cepstral analysis is performed for each frequency band and a voiced/unvoiced decision for each frequency band is made based on the height of the cepstrum peak as a measure of periodicity.
In the excitation model proposed by Makhoul et al., the excitation signal consists of the sum of a low-pass periodic source and a high-pass noise source. The low-pass periodic source is generated by filtering a white pulse source with a variable cut-off low-pass filter. Similarly, the high-pass noise source was generated by filtering a white noise source with a variable cut-off high-pass filter. The cut-off frequencies for the two filters are equal and are estimated by choosing the highest frequency at which the spectrum is periodic. Periodicity of the spectrum is determined by examining the separation between consecutive peaks and determining whether the separations are the same, within some tolerance level.
In a second excitation model implemented by Kwon and Goldberg, a pulse source is passed through a variable gain low-pass filter and added to itself, and a white noise source is passed through a variable gain high-pass filter and added to itself. The excitation signal is the sum of the resultant pulse and noise sources with the relative amplitudes controlled by a voiced/unvoiced mixture ratio. The filter gains and voiced/unvoiced mixture ratio are estimated from the LPC residual signal with the constraint that the spectral envelope of the resultant excitation signal is flat.
In the multiband excitation model proposed by Griffin and Lim, a frequency dependent voiced/unvoiced mixture function is proposed. This model is restricted to a frequency dependent binary voiced/unvoiced decision for coding purposes. A further restriction of this model divides the spectrum into a finite number of frequency bands with a binary voiced/unvoiced decision for each band. The voiced/unvoiced information is estimated by comparing the speech spectrum to the closest periodic spectrum. When the error is below a threshold, the band is marked voiced, otherwise, the band is marked unvoiced.
The Fourier transform of the windowed signal s(t,n) will be denoted by S(t,w) and will be referred to as the signal Short-Time Fourier Transform (STFT). Suppose s0(n) is a periodic signal with a fundamental frequency w0 or pitch period n0. The parameters w0 and no are related to each other by 2π/w0=n0. Non-integer values of the pitch period n0 are often used in practice.
A speech signal s0(n) can be divided into multiple frequency bands using bandpass filters. Characteristics of these bandpass filters are allowed to change as a function of time and/or frequency. A speech signal can also be divided into multiple bands by applying frequency windows or weightings to the speech signal STFT S(t,w). | {
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The present invention relates generally to rotational control apparatus, particularly to provisions supported directly by the shaft for providing fluid pressure to a rotation control apparatus portion rotatable with respect to the shaft, and specifically to dual-rotary union, rotational isolation adapters.
Problems exist particularly in connection with fluid actuated rotational control apparatus. In such rotational control apparatus, a source of fluid pressure is in fluid communication with a part of the rotational control apparatus such as a piston which is to be actuated. If such part is rotating and the source of fluid pressure is stationary, as it generally is, problems exist in regard to providing such fluid communication.
These problems particularly arise in clutches or the like, since brakes generally have a portion which is stationary with respect to the source of fluid pressure or external housing. In the case of brakes, fluid communication and actuation may often be made with respect to such stationary portion. Clutches, in contradistinction, are generally composed of at least two portions, with one portion connected to the shaft either directly or through intervening elements, and another portion which is rotatably mounted with respect to the shaft and which interacts with the first portion. Thus, suitable provisions such as rotary unions must be provided for allowing fluid communication between a stationary source of fluid pressure and one rotating portion of the clutch.
If the portion of the rotational control apparatus desired to be actuated rotates with the shaft, the rotary union could be directly or indirectly connected to the shaft. For example, U.S. Pat. No. 4,408,685 assigned to Horton Industries, Inc. discloses structure of this type to solve this problem.
On the other hand, if the portion of the rotational control apparatus desired to be actuated is rotatably mounted with respect to the shaft, the rotary union could be directly or indirectly connected to the portion which is rotatably mounted with respect to the shaft. Often this portion is in the form of a housing and the rotary union is connected to an end cap for this housing. An example of such an end cap approach is shown in U.S. Pat. No. 4,425,993 also assigned to Horton Industries, Inc. When an end cap approach is used, however, and especially if the apparatus has a large radius, the end cap approach can present significant design problems. The end cap adds weight, adds inertia, and increases costs. The end cap requires careful machining to allow for balance. The end cap provides centrifugal problems because of the large amount of mass radially spaced from the shaft upon which it is generally centered for rotation.
In situations where it is wished to provide fluid pressure from a stationary source to a rotational control apparatus such as a clutch, in particular, where the portion to which fluid pressure is desired is rotatably mounted with respect to the shaft, it has been discovered that no solution was known where the rotary union is mounted directly to the shaft but rotatably isolated from the shaft to avoid the problems encountered by end cap type approaches. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of Invention
The present invention relates to a high-voltage pulse protection device. More particularly, the present invention relates to a high-voltage pulse protection device for a video apparatus.
2. Description of Related Art
Lightning bolts are natural phenomenon. Each lightning bolt has a voltage between one hundred million volts and one billion volts and has a current between twenty thousand amperes and forty thousand amperes. Therefore, if an electrical apparatus without proper insulation is struck by lightning, the electrical apparatus will be seriously damaged.
A typical video apparatus or display apparatus (such as a digital/analog TV turner, a digital/analog TV card/box, a plasma/LCD TV, a hand-held mobile TV, a set-top box, a high definition TV, a digital TV receiver, a satellite TV card/box, a car TV, a TV signal transmitter, a DVD player, a video tape player/recorder, a security video system, an internet security video system or a traffic video system) has an input terminal, a video processing module, and a cable. The input terminal (such as an antenna) receives a TV signal. The cable connects the input terminal and the video processing module to transfer the TV signal to the video processing module.
When lightning strikes the input terminal, the high voltage current from the lightning bolt passes through the cable and also damages the video processing module. For example, when an antenna located on a rooftop is struck by lightning, the high voltage current from the lightning bolt passes through the antenna cable and also damages the TV located in the house. Furthermore, a user may be severely injured by the lightning if he/she touches one of the TV conductors.
How to provide a device to protect the video apparatus from being damaged by high voltage currents induced by lightning strikes and other high-voltage pulses is what both manufacturers and users are longing for. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The invention relates to a speaker assembly. More particularly, the invention relates to a speaker assembly with reduced size and weight, yet retaining robust structural integrity and simplified integration allowing optimum placement and excellent performance of the speaker assembly within an aircraft.
2. Description of the Related Art
The current global community has made it possible for people from around the country, and around the world, to interact for both business and personal reasons. For many people, this requires they spend considerable time traveling from one location to another location. More often than not, these people travel in aircraft.
Whether these people travel in private or commercial aircraft, they desire high quality entertainment during the many hours they spend within the confines of an aircraft. While high quality entertainment, for example, digital video with CD quality sound, is readily available for theatre and home use, the weight and size requirements for use of such equipment in an aircraft makes it very difficult to incorporate high fidelity systems within an aircraft. This problem is especially pronounced for audio speaker assemblies when one attempts to meet the size, weight and shape requirements for use in aircraft.
The aircraft industry places a high priority upon component weight and size reduction. Range and payload are adversely affected by conventional terrestrial designs. These concerns are notable when one attempts to make changes within smaller private jets. For example, a small increase in the weight carried by an aircraft results in a substantial increase in the fuel consumption of the aircraft. In addition, the limited space available within an aircraft dictates the use of available space within the aircraft be carefully considered by those responsible for ensuring the comfort of passengers.
Lightweight and compact audio speakers are currently available. These speakers, however, substantially compromise sound quality for reduction in size and weight. With this in mind, an individual wishing to add an audio system to an aircraft must make a choice between high fidelity speakers, which do not suit the size and weight requirements of the aircraft, or lower quality speakers providing desirable size and weight characteristics.
Another concern encountered in the incorporation of speakers within an aircraft is the fact the speakers are generally confined within an enclosed space offering little in the way of airflow for cooling the driving components of the loudspeakers. In addition, the small spaces available within an aircraft also dictate that the speaker housing be relatively small. This further creates heating problems as little air is available within the housing for the cooling of speaker components. As such, speakers are susceptible to overheating, which may result in damage thereto or failure of the component.
More particularly, and as those skilled in the art will certainly appreciate, the voice coil of a conventional driver generates heat which is then dissipated to the surrounding driver structure, that is, the driver magnet, etc. This heat must be “bled off” to maintain the driver at an appropriate operating temperature or the performance of the speaker will be compromised.
A need, therefore, exists for a speaker assembly providing high-fidelity sound, while also accommodating the size and weight constraints of an aircraft. The present invention provides such a speaker assembly. | {
"pile_set_name": "USPTO Backgrounds"
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Intravascular diseases are commonly treated by relatively non-invasive techniques such as percutaneous transluminal angioplasty (PTA) and percutaneous transluminal coronary angioplasty (PTCA). These therapeutic techniques are well known in the art and typically involve use of a guide wire and a balloon catheter, possibly in combination with other intravascular devices. A typical balloon catheter has an elongate shaft with a balloon attached to its distal end and a manifold attached to the proximal end. In use, the balloon catheter is advanced over the guide wire such that the balloon is positioned adjacent a restriction in a diseased vessel. The balloon is then inflated and the restriction in the vessel is opened.
Vascular restrictions that have been dilated do not always remain open. In approximately 30% of the cases, a restriction reappears over a period of months. The mechanism of this restenosis is not understood. The mechanism is believed to be different from the mechanism that caused the original stenosis. It is believed that rapid proliferation of vascular smooth muscle cells surrounding the dilated region may be involved. Restenosis may be in part a healing response to the dilation, including the formation of scar tissue.
Intravascular radiation, including thermal, light and radioactive radiation, has been proposed as a means to prevent or reduce the effects of restenosis. For example, U.S. Pat. No. 4,799,479 to Spears suggests that heating a dilated restriction may prevent gradual restenosis at the dilation site. In addition, U.S. Pat. No. 5,417,653 to Sahota et al. suggests that delivering relatively low energy light, following dilatation of a stenosis, may inhibit restenosis. Furthermore, U.S. Pat. No. 5,199,939 to Dake et al. suggests that intravascular delivery of radioactive radiation may be used to prevent restenosis. While most clinical studies suggest that thermal radiation and light radiation are not significantly effective in reducing restenosis, some clinical studies have indicated that intravascular delivery of radioactive radiation is a promising solution to the restenosis enigma.
Since radioactive radiation prevents restenosis but will not dilate a stenosis, radiation is preferably administered during or after dilatation. European Patent No. 0 688 580 to Verin discloses a device and method for simultaneously dilating a stenosis and delivering radioactive radiation. In particular, Verin '580 discloses balloon dilatation catheter having an open-ended lumen extending therethrough for the delivery of a radioactive guide wire.
One problem associated with the open-ended lumen design is that bodily fluids (e.g., blood) may come into contact with the radioactive guide wire. This may result in contamination of the bodily fluid and require the resterilization or disposal of the radioactive guide wire. To address these issues, U.S. Pat. No. 5,503,613 to Weinberger et al. proposes the use of a separate closed-ended lumen in a balloon catheter. The closed-ended lumen may be used to deliver a radioactive guide wire without the risk of contaminating the blood and without the need to resterilize or dispose of the radiation source.
The closed-ended lumen design also has draw backs. For example, the addition of a separate delivery lumen tends to increase the overall profile of the catheter. An increase in profile is not desirable because it may reduce flow rate of fluid injections into the guide catheter and it may interfere with navigation in small vessels.
Another problem with both the open-ended and closed-ended devices is that radiation must travel through the fluid filled balloon in order to reach the treatment site. While this is not a problem for gamma radiation, it poses a significant problem for beta radiation which does not penetrate as well as gamma radiation. Beta radiation is considered a good candidate for radiation treatment because it is easy to shield and control exposure. In larger vessels (e.g., 0.5 cm or larger), a fluid filled balloon absorbs a significant amount of beta radiation and severely limits exposure to the treatment site.
Other intravascular treatments, including delivery of radioactive radiation have been proposed as a means to prevent or reduce the effects of restenosis. For example, U.S. Pat. No. 5,199,939 to Dake et al. suggests that intravascular delivery of radiation may inhibit restenosis. Dake et al. suggest delivering radiation within the distal portion of a tubular catheter. Fischell, in the publication EPO 0 593 136 A1, suggests placing a thin wire having a radioactive tip near the site of vessel wall trauma for a limited time to prevent restenosis. Problems exist in attempting to provide uniform radiation exposure using a point or line source. Specifically, as the radiation varies inversely with the square of distance for a point source and inversely with distance for a line source laying off center near one vessel wall may significantly overexpose the nearby wall while underexposing the further away wall. This is especially critical for beta radiation which is absorbed by tissue and blood at a relatively short distance from the source.
Bradshaw, in PCT publication WO 94/25106, proposes using an inflatable balloon to center the radiation source wire tip. In PCT publication WO 96/14898, Bradshaw et al. propose use of centering balloons which allow blood perfusion around the balloon during treatment. U.S. Pat. No. 5,540,659 to Tierstein suggests use of a helical centering balloon, attached to a catheter at points about the radiation source to allow perfusion through the balloon, between the balloon and radiation ribbon source.
Use of continuous centering balloons, having a beta radiation source within, significantly attenuate the beta radiation when filled with inflation fluid and they may also allow the radiation source to "warp" when placed across curved vessel regions, allowing the balloon to bend but having the central radiation source lying in a straight line between the two ends. Segmented centering balloons may improve the warping problem but may also increase beta attenuation by allowing blood to lie or flow between the beta source and vessel walls. Balloons allowing external perfusion in general have the aforementioned beta attenuation problem. What remains to be provided is an improved apparatus and method for delivering uniform radiation to vessel interiors to inhibit restenosis. | {
"pile_set_name": "USPTO Backgrounds"
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1. Technical Field
The present invention relates to a liquid droplet discharge apparatus that discharges liquid droplets to a work, to a liquid supply device thereof, to an electro-optical device, and to an electronic apparatus.
2. Related Art
Liquid droplet discharge apparatuses have been used as image drawing systems in which liquid droplets are discharged to a work according to an ink-jet method. These image drawing systems have been used in some cases to manufacture electro-optical devices such as flat panel displays.
A liquid droplet discharge apparatus discharging liquid droplets using an inkjet method has a head that discharges liquid droplets and an ink cartridge that supplies liquid to the head. The head may be connected to the ink cartridge by an ink supply tube (for example, see Japanese Unexamined Patent Application Publication No. 61-53052 (page 3 and FIG. 1)). The ink supply tube employs a double tube structure in order to prevent permeation of air or the like. Accordingly, air may be prevented from permeating from the external environment into ink in the tube.
However, such a double structure ink supply tube has the following problems.
An outer tube and an inner tube are intended to capture air permeating from the external environment. However, since the amount of air becomes saturated as the amount of air between the outer tube and the inner tube increases, the air is likely to permeate into the inner tube.
In addition, when the inner tube and the outer tube are bent, the inner circumferential surface of the outer tube rubs against the outer circumferential surface of the inner tube, which results in breakage of the tubes. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to an exhaust gas purifying catalyst adapted, for example, to be mounted in an exhaust pipe of a vehicle, and more specifically to an exhaust gas purifying catalyst comprising a catalyst layer formed on a surface of a honeycomb-shaped substrate in a manner that it contains a composite oxide which includes cerium (Ce) and zirconium (Zr) and has a hollow structure, and a catalytic metal supported by the composite oxide.
2. Description of the Related Art
As is commonly known, an air-fuel ratio of exhaust gas discharged from an engine is varied depending on engine operation states, such as acceleration, deceleration and steady states, and, in general, hydrocarbon (HC), carbon monoxide (CO) and nitrogen oxides (NOx) contained in the exhaust gas can be simultaneously converted only in a certain limited range around a theoretical air-fuel ratio of 14.7. As one technique of allowing an air-fuel ratio during acceleration or deceleration to fall with the purifying range, there has been known a technique of incorporating an oxygen-absorbing material into an exhaust gas purifying catalyst. This oxygen-absorbing material is operable, when oxygen in exhaust gas is in an excess state (lean air-fuel ratio), to absorb and store oxygen, and, when oxygen in exhaust gas is in a deficient state (rich air-fuel ratio), to release the oxygen stored therein, so as to allow the lean and rich air-fuel ratios to fall within the conversion range.
CeO2 (ceria) is known as one of the oxygen-absorbing materials. If CeO2 is used by itself, a specific surface area thereof is reduced when being exposed to heat of exhaust gas, and an oxygen absorbing/releasing capability will deteriorate due to change in properties thereof. For this reason, a composite oxide, such as CeZr-based composite oxide containing ZrO2 (zirconia), is known, and a catalytic metal is often supported by a carrier made of such a composite oxide.
As with the oxygen-absorbing material, it is also known to employ alumina as an oxide carrier for supporting a catalytic metal. Alumina is known as an oxide carrier generally having a higher thermal resistance and a larger specific surface area than those of the oxygen-absorbing material. While alumina has no oxygen absorbing/releasing capability, it excels in being able to support a catalytic metal in a highly dispersed state. With a view to further increasing the specific surface area of alumina having the above properties, a technique of forming alumina to have a hollow structure is disclosed, for example, in Japanese Patent Laid-Open Publication Nos. 11-314035 and 2001-347167. Specifically, the Japanese Patent Laid-Open Publication No. 11-314035 discloses a technique of spraying a water/oil (W/O) emulsion solution comprising a primary component of aluminum (Al) and containing an element belonging to Groups IIa to VIIa and IIb in the periodic table, into a furnace chamber, and burning it therein at 900° C. or less to obtain an oxide carrier with a hollow structure having an outer diameter of 20 to 2000 nm and a shell thickness of several ten nm. The Japanese Patent Laid-Open Publication No. 2001-347167 discloses a technique of spraying a W/O emulsion solution comprising a primary component of Al and containing a rear-earth metal, and burning it at 1000° C. or less (preferably in the range of 650 to 950° C.) to obtain an oxide carrier with a hollow structure having an outer diameter of 20 to 2000 nm and a shell thickness of 50 nm or less.
As mentioned above, alumina has no oxygen absorbing/releasing capability. Thus, even if cerium (Ce) as rare earth metal is combined with alumina, a sufficient oxygen absorbing/releasing capability cannot be obtained. Form this point of view, the inventors conceived a CeZr composite oxide having a hollow structure without containing alumina. However, the CeZr composite oxide originally has a relatively small specific surface area and poor thermal resistance. Thus, even if the CeZr composite oxide is formed to have a hollow structure, the hollow structure will be destroyed after being exposed to heat of exhaust gas, to cause a problem about a significant decrease in specific surface area and a difficulty in ensuring adequate conversion performance. | {
"pile_set_name": "USPTO Backgrounds"
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1. Technical Field
The present invention relates to a light emitting device comprising a light emitting element, and to a circuit board comprising this light emitting device and a mounting board.
2. Background Information
Light emitting devices comprising a light emitting element (such as a light emitting diode or a laser diode) have been widely used in the past as the light source for LCD television backlights, lighting fixtures, optical communications devices, and so forth.
Light emitting devices are generally classified as either a top-view type or a side-view type, according to the direction in which the light emitted by the light emitting element is taken off. With a top-view type of light emitting device, the emitted light from a light emitting element 10 is taken off in a direction perpendicular to the mounting face. With a side-view type of light emitting device, the emitted light from the light emitting element is taken off in a direction that is parallel to the mounting face.
With a light emitting device such as this, the top face of the light emitting device is chucked and conveyed onto the mounting board by a nozzle of the device that mounts the light emitting device, and is then mounted on the mounting face of the mounting board.
In Japanese Laid-Open Patent Application 2010-62272 (hereinafter referred to as the “Patent Literature 1”), there is also a known light emitting device manufactured by cutting a lead frame and a molded article that is integrally molded with the lead frame, in order to manufacture many light emitting devices in a short time and increase production efficiency. The light emitting device in Patent Literature 1 has a substantially cuboid shape, and has a bottom face that abuts the mounting face, a top face that is the light emission face opposite the bottom face, and four side faces that are contiguous with the bottom face and the top face. The light emitting device in Patent Literature 1 has a pair of flat leads embedded in the molded article. One of the flat leads has a face on which a light emitting element is placed on the top face side, and the other flat lead has a face that is electrically connected to the light emitting element on the top face side. The bottom face side of the pair of flat leads had by the light emitting device in Patent Literature 1 is exposed from the bottom face of the light emitting device over a large enough area to allow a good solder bond. Therefore, the light emitting device in Patent Literature 1 is a top-view type of light emitting device that has a terminal on the bottom face and has a light emission face on the top face. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to an outboard motor carrier. More particularly, the invention relates to an outboard motor carrier for an automotive vehicle having a chassis and a body mounted on the chassis and having a top and a rear.
Outboard motor carriers are described in the following U.S. patents. U.S. Pat. No. 2,247,128, issued to Levey on June 24, 1941, U.S. Pat. No. 2,663,474, issued to Kelly on Dec. 22, 1953, U.S. Pat. No. 2,762,542, issued to Hodgeman on Sept. 11, 1956, U.S. Pat. No. 2,887,237, issued to Ellingson on May 19, 1959, U.S. Pat. No. 2,895,628, issued to Gebhart on July 21, 1959 and U.S. Pat. No. 3,039,634, issued to Hobson et al on June 19, 1962.
Objects of the invention are to provide an outboard motor carrier of simple structure, which is inexpensive in manufacture, installed with facility and convenience on new and existing automotive vehicles, used with facility and convenience, and functions efficiently, effectively and reliably to releasably securely mount an outboard motor for transportation, as desired. | {
"pile_set_name": "USPTO Backgrounds"
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Phase-change materials are materials that can switch, under the effect of heat, between a crystalline phase and an amorphous phase. Since the electrical resistance of an amorphous material is significantly higher than the electrical resistance of a crystalline material, this phenomenon can be useful for defining two memory states, for example 0 and 1, differentiated by the resistance measured across the phase-change material. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a stent. More particularly, it relates a sandwich stent which provides a mechanical barrier for prohibiting the growth of tissue through an artery implanted stent.
2. Description of the Prior art
In the prior art, stents are well known for use in minimally invasive surgery or interventional procedures for attaching to the inner walls of a blood vessel where a procedure such as a balloon angioplasty has been performed. Such prior art stents are essentially metallic scaffolds that are left in the arteries to prevent the arteries from collapsing back to their original form due to a phenomenon called elastic recoil. Such recoil can be common after the dilatation of a balloon.
Although the subject prior art stents have been generally successful in preventing elastic recoil, they have not been successful in the prevention of instent restenosis. Such phenomenon occurs when tissue grows into and through the struts of the stent due to openings in the stent struts. The tissue is then permitted to grow into the lumen and reocclude the artery, whereby a balloon angioplasty procedure most be repeated.
In an effort to prohibit instent restenosis, stents were provided with covering material. Such can be seen in U.S. Pat. No. 5,562,728 to Lazarus et al. wherein a helical wrap of ribbon is attached to a covering material; the attachment being only at the ends. U.S. Pat. No. 5,578,071 to Parodi et al. show a vascular graft that has two stents attached at the ends of the tubular conduit, where at one wire is provided and woven into a distal end, or lower end, of the graft, the wire permitting the distal end of the graft to conform to and sealingly engage within the artery of the patient.
When conveying a stent to its point of use, it is imperative that any covering material be secured about the stent in a secure and tight fashion to preclude the stent from being "hung up" in some area of the vascular system of the patient while it is being conveyed to the point of use. The prior art stents do not adequately secure the cover to the stent to prohibit such hang up. Further, the prior art devices have a very large profile that require being cut down by a surgeon and inserted into the body through a very large opening. Accordingly, minimally invasive surgery, in its strictest meaning, is not provided. Because of the large profile, the prior art devices are not useable in every area of the body, but only in larger arteries.
A stent is needed that overcomes the problems in the prior art. Such a stent needs to be low in profile yet provide the necessary mechanical barrier to prevent instent restenosis. An improved means of securement is needed to prevent the covering material hang up. Further, providing such an improved stent with a low profile can be used in widespread applications and not be limited to large artery procedures. | {
"pile_set_name": "USPTO Backgrounds"
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Guitar picks are typically small, flat apparatuses that are triangular shaped with rounded edges. The pick can be used to pluck or strum stringed musical instruments such as guitars. Use of a guitar pick can help generate a higher quality sound and improve the ability of a musician to strike large chords. A pick is generally made of a rigid material such as metal or plastic and is lightweight and may vary in thickness based on the desired sound quality.
Conventionally, picks have been designed to be held between the thumb and one or more fingers to assist musicians while playing instruments such as the guitar. Drawbacks of this technique, however, include difficulty of maintaining a fixed position and proper control of the pick and proper tension on the pick while playing an instrument. For example, if the pick is held too loosely, it could cause the pick to shift in the musician's fingers, affecting the ability of the musician to retain a proper grip on the pick. Conversely, holding the pick too tightly can interfere with the play of the instrument by distorting the sound. Sound quality can also be negatively impacted if the pick is not held at a proper 90 degree angle to the strings.
Mounting apparatuses such as rings or band-like structures have been designed to secure a guitar pick onto a user's finger or thumb. Such designs, however, are directed towards preventing accidental dropping of a guitar pick and/or providing a user with the ability to interchangeably alternate between the use of a user's finger and a guitar pick to strum or pluck instrument strings. These designs do not address the issues of maintaining a proper tension and angle of a guitar pick relative to an instrument.
Therefore, there is a need for a guitar pick that aids in improving the ability of a musician to effectively control tension and alignment of a guitar pick without losing a sufficient grip on the guitar pick while maintaining a high quality tone. | {
"pile_set_name": "USPTO Backgrounds"
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Self-injection-locked (SIL) radar is conventionally applied for detecting important vital signs of biological subject (e.g. respiration and heartbeat). The principle of detection is that SIL radar radiates a radio-frequency (RF) signal to a subject, and the RF signal reflected from the subject is injected into the SIL radar to bring the SIL radar to a SIL state and generate a SIL signal. The displacement of the subject affects the frequency of the RF signal to cause a Doppler effect, for this reason, the SIL signal contains Doppler shift component caused by the displacement of the subject, so that the displacement information of the subject can be obtained by analyzing the SIL signal of the SIL radar in principle. However, when the displacement of the subject is more than 1/10 operating wavelength, the frequency information of the subject cannot be determined accurately because of nonlinear distortion of the waveform caused by SIL phenomenon. No matter the subject's movement is large or small, the conventional SIL radar cannot detect the displacement of the subject based on the variation of the waveform. The conventional SIL radar is limited to detect the vibration frequency of the subject in small movement, so it is only applied for detecting the frequency of the weak vibration subject, e.g. respiration and heartbeat. In addition, the conventional SIL radar cannot even detect the frequency of the vibration when the movement of the subject is large. | {
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It is known to provide a gaming system which comprises a game controller arranged to randomly select and cause the display of several symbols from a predetermined set of symbols, and to determine a game outcome, such as a game win, based on the displayed symbols. Such gaming systems may commonly be implemented as a stepping machine provided with mechanical reels that each carry several symbols of the set, or a video machine wherein selected symbols are displayed on virtual reels on a graphical display device. Win outcomes can occur based on symbols appearing in one or more horizontal lines, diagonal lines, or any other predetermined way. Typically five vertically aligned reels are provided on the display (although less or more may be provided). Each reel displays three symbols high in the display window for the reel (although, again, this may be more or less symbols high).
Many gaming machines are of the type where the game outcome (selection of symbols) is totally randomly generated, usually on the basis of a random number generator selecting symbols from a symbol table (cross referenced with random numbers). Other types of gaming system are known where player interaction is required to facilitate selection of symbols. For example, “Pachislo” games require a player to push a button which causes the spinning reels to come to a stop.
Pachislo and other types of “skill stop” games rely on a certain amount of player skill to enable the player to stop the reel (virtual or actual) to select the symbol they desire for the desired game outcome. These types of gaming systems may not wholly depend on player skill. A group of symbols may be pre-selected, for example by utilizing a random number generator, and the player skill stop may only be exercised to select from these “pre-selected” symbols. It may appear to the player that he has more than this group of symbols to select from, but the gaming machine will only allow one or more of these symbols to be selected. The gaming machine operates to maintain the return to player (rtp) specified by the operator.
Skill stop games generally use a “slip” system. When the player pushes a button to stop the reels, the reel can stop plus or minus a couple of symbols on the reels. For example, let us say the reel carries symbol numbers “1”, “2”, “3”, “4”, “5”, “6”, “7”, “8”, and “9”. If the player pushes a “stop” button when the “5” is shown on a gaming machine display, when the reel comes to rest it may be “5”, “4”, “3” or “2”.
In skill stop games, it is known to vary the rotation speed (or apparent rotation speed, if a virtual reel) of a reel in order to vary the skill level requirement of a player attempting to stop the reel on a desired symbol. For example, in some circumstances a reel may be slowed down so that it is easier for a player to make reel stop predictions. A determination as to when to vary the speed of rotation of the reel is usually made by an internal decision of the gaming machine.
While such gaming systems provide users with enjoyment, a need exists for alternative gaming systems in order to maintain or increase player enjoyment. | {
"pile_set_name": "USPTO Backgrounds"
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There are two general types of AGV guidance systems, rail systems and non-rail systems. In the first type of system, a pathway is formed out of rails. These rails may support an AGV or merely guide the AGV's wheels as they roll along the ground. In a non-rail system, the AGV may include detectors for detecting and following a wire in the ground that marks out a pathway, or a controller for following a set of commands to navigate between various types of reference markers. Each of these systems has certain advantages and drawbacks, and the choice of which system to use is normally based on many factors such as the needs of the particular user and the environment in which the system will operate.
Rail guidance allows for precise control over the position of an AGV. Where only a limited number of pathways are needed, and where these pathways do not need to be changed frequently, rail guidance offers a relatively simple method of keeping an AGV on a selected path. One of the biggest drawbacks to rail guidance, however, is that switches are needed to direct AGV's from one pathway to another. These switches are relatively costly and include moving parts that can wear out. In addition, each switch must be connected to a power source, a sensor for determining the position of the switch, and a controller for moving the switch from one position to another at appropriate times. The switches are often connected to a controller and to one another by a series of wires that run along the pathways, and these wires are expensive to install and maintain. Furthermore, the wires must be reconfigured each time the system is modified. Another disadvantage to such systems is that the rails themselves are generally raised off the ground and can interfere with the free movement of people and other vehicles.
Non-rail guidance systems offer increased design flexibility since pathways can be changed by reprogramming the AGV's or their controllers and without removing and re-laying rails. Moreover, because each vehicle receives or is programmed with instructions concerning the pathway to follow, switches are not needed to shift a vehicle from one path to another. However, because AGV's in such a system can stray from their pathways, extra care is required to make sure that each AGV is in its intended location and often this entails virtually constant communication with each AGV in the system. The quality of the communication link and the speed at which information about the AGV's and their positions can be processed also limits the maximum rate of travel of these systems. Moreover, collision avoidance becomes more complicated when AGV's travel along pathways that are not defined by rails. The need to constantly monitor and control a large number of AGV's, and to keep them on course and to avoid collisions, requires a significant amount of processing power which can make non-rail guidance systems more complex and expensive to operate than rail systems.
For high speed transport, that is for speeds in the range of 2200 feet per minute, rail guidance has traditionally been the only practical method for guiding an AGV. This is in part due to a perception that it is unsafe to operate vehicles at high speeds without physical path constraints and partly due to control problems. For example, the servo-control mechanisms used to steer AGV's often cannot respond quickly enough to the changing location of a guide wire in order to control a fast-moving vehicle. In addition, the signal to noise ratio of the position sensors may be too low to allow them to accurately sense the presence of a wire in the ground or to communicate reliably with a central controller when moving rapidly. Therefore, in applications where high speeds are needed, it has heretofore been necessary to use rail based control with all of its attendant drawbacks. | {
"pile_set_name": "USPTO Backgrounds"
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In the manufacturing industry, like the chemical, pharmaceutical, coating, recycling and oil industry, there exists a broad variety of sources for emissions which are released in the environment, which is not desirable. For example, in chemical reactions, emissions of reaction components, additives and solvents may be released. During coating of cars, vapors of coatings, additives and solvents may be released. During recycling of polymers, monomers or oligomers of the hydrolyzed polymer may be released. During cleaning of reactors, chemicals and solvents may be released.
Before, during and after the polymerization reaction for the manufacture of thermoplastic polymers like polyamides, polyester, polyolefins, polycarbonates, polystyrenes, polyacrylonitriles, polyurethanes, polysulfones, polyethersulfones, polyvinylchloride, copolymers and mixtures thereof, monomer vapors may be released in the environment from transportation tanks, storage tanks, pipelines, ducts, polymerization reactors, polymer melts, polymer strands, water bath, cutters, dryers and the like. During thermoplastic polymer processing like injection molding or extrusion, the thermoplastic polymers are for example extruded through an extruder into strands for chip production or into films, fibers, profiles, tubes and the like. During the extrusion at a temperature of from about 180.degree. to about 350.degree. C., monomer or oligomer vapors, compounds formed by thermal evaporation, thermal decomposition, or vapors of additives are released from the surface of the extruded polymers, which are leaving the nozzle of the extruder. These vapors evaporate immediately into an aerosol that would form deposits in the neighborhood of the extruder and therefore, must be removed, which is usually done by the quench air removal. The exhaust air is usually released in the environment, which is not desirable.
During the manufacture of synthetic yarns, a heat setting step is applied to the yarn for setting a twist in the yarn. In a heat setting unit, heat in form of hot air and/or steam is applied to the yarn. The air and/or steam contains emissions like monomers, oligomers and finish oils, when it exits the heat setting unit, which should be removed.
U.S. Pat. No. 4,676,807 discloses a process for removal of liquid aerosols from gaseous streams by passing the stream through a coalescing filter. In the examples of this patent, oil and water aerosols were tested.
U.S. Pat. No. 4,759,782 which is a C.I.P. of an application which issued as U.S. Pat. No. 4,676,807 described above, discloses the coalescing filter for removal of liquid aerosols from gaseous streams.
The technical bulletin Wringer.RTM., Des Champs Laboratories Inc., VA, describes a process for the dehumidification of air.
An object of the present invention was to provide a process for removing emissions from a broad variety of emission sources.
Another object of the present invention was to provide a process for removing of emissions from polymerization operations and thermoplastic polymer processing operations.
Another object was a process for removing emissions from fiber spinning operations.
Another object was a process for removing emissions from a heat setting operation for the manufacture of synthetic yarns.
Still another object was a process for removing emissions from a heat setting operation for the manufacture of polycaprolactam yarns. | {
"pile_set_name": "USPTO Backgrounds"
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The determination of the amino terminal amino acid sequences of proteins and peptides is an essential analysis for their identification or confirmation.
However, 60% or more of the soluble proteins derived from eukaryote reportedly have the .alpha.-amino group at their amino terminal blocked by either an acetyl group or another protecting group; and in the Edman degradation method, a well-established commonly used method for. analyzing an amino acid sequence from the amino terminal, proteins and peptides of which amino terminal is blocked by a protecting group cannot be analyzed.
As the protecting groups blocking the amino terminal of proteins and peptides, formyl group, acetyl group, myristoyl group, pyroglutamyl group, dimethyl group, glucuronyl group, glycosyl group and trimethyl group have been reported. As the method for analyzing an amino terminal amino acid sequence for such blocked proteins, there can be employed the Edman degradation method applied after removing a protecting group.
The removal of protecting groups includes a method using an enzyme and a chemical method. However, an enzymatic method has a drawback of a lack of versatility, since different enzymes are used depending on the kinds of protecting groups to be removed. For example, acylamino acid releasing enzyme is used in the case of acetyl groups, and pyroglutamyl peptidase in the case of pyroglutamyl groups. Also, as to chemical method, no versatile methods have been developed to date. In addition, because there is no known method of identifying the protecting group when the amino terminal is blocked thereby, when the protecting group is actually removed, there are no other alternatives except that a number of methods for removing protecting group depending on respective protecting groups are attempted one by one. Furthermore, since there is no effective method for removing a protecting group available for the proteins and peptides blocked with myristoyl group, it is impossible to determine their amino acid sequences from the amino terminal.
Incidentally, as the peptidases isolated from Pyrococcus furiosus, the peptidases acting on an amino terminal portion of a peptide, there have been known an aminopeptidase (Japanese Patent Laid-Open No. Hei 6-319566), a pyroglutamyl peptidase (Japanese Patent Laid-Open No. Hei 7-298881), and a methionine aminopeptidase (Japanese Patent Laid-Open No. Hei 8-9979). Among these peptidases, the pyroglutamyl peptidase possesses an activity for releasing of the amino terminal pyroglutamyl group, but does not act on other protecting groups, e.g., acetyl groups. In addition, the other two kinds of enzymes both cannot act on amino terminal blocked by protecting groups.
As described above, the existing method for analyzing amino terminal amino acid sequence has the drawback of a lack of versatility when applied to proteins and peptides of which amino terminal is blocked by protecting groups. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a magnetic random access memory (MRAM) which stores “1”- and “0”-data using a magnetoresistive effect.
2. Description of the Related Art
In recent years, many memories which store data by new principles have been proposed. One of them is a magnetic random access memory (MRAM) using a tunneling magnetoresistive (to be referred to as TMR hereinafter) effect. As a proposal for a magnetic random access memory, for example, the following nonpatent reference 1 is known: Roy Scheuerlein et al, “A 10 ns Read and Write Non-Volatile Memory Array Using a Magnetic Tunnel Junction and FET Switch in each Cell”, 2000 ISSCC Digest of Technical Papers (U.S.A.), February 2000, pp. 128-129 is known.
A magnetic random access memory stores “1”- or “0”-data in an MTJ (Magnetic Tunnel Junction) element using the TMR effect for read operation. As the basic structure of an MTJ element, an insulating layer (tunneling barrier) is sandwiched between two magnetic layers (ferromagnetic layers).
Data stored in the MTJ element is determined on the basis of whether the magnetizing states of the two magnetic layers are parallel or antiparallel. “Parallel” means that the two magnetic layers have the same magnetizing direction. “Antiparallel” means that the two magnetic layers have opposite magnetizing directions.
When the magnetized state of the MTJ element is “parallel”, the tunneling resistance of the insulating layer (tunneling barrier layer) sandwiched between the two magnetic layers of the MTJ element is minimized. For example, this state is defined as a “1”-state. When the magnetized state of the MTJ element is “antiparallel”, the tunneling resistance of the insulating layer (tunneling barrier layer) sandwiched between the two magnetic layers of the MTJ element is maximized. For example, this state is defined as a “0”-state.
Currently, various kinds of cell array structures have been examined for a magnetic random access memory from the viewpoint of increasing the memory capacity or stabilizing write/read operation.
For example, currently, a cell array structure in which one memory cell is formed from one MOS transistor and one MTJ element is known. Additionally, a magnetic random access memory which has such a cell array structure and stores 1-bit data using two memory cells so as to implement stable read operation is also known.
However, in these magnetic random access memories, it is difficult to increase the memory capacity. This is because one MOS transistor corresponds to one MTJ element in these cell array structures.
For example, array structures in which a plurality of MTJ elements are connected in parallel have been proposed (e.g., patent reference 1 (Japanese Patent Application No. 2000-296082) and patent reference 2 (Japanese Patent Application No. 2001-350013)). According to these cell array structures, since one MOS transistor corresponds to a plurality of MTJ elements, the memory capacity can be increased as compared to the cell array structure having memory cells each formed from one MTJ element and one MOS transistor.
In the techniques disclosed in patent references 1 and 2, however, the MTJ elements are two-dimensionally arranged in one plane. For this reason, the integration density of MTJ elements cannot be sufficiently increased.
To solve this problem, a technique for three-dimensionally arranging MTJ elements on a semiconductor substrate has been proposed. More specifically, in this technique, a plurality of MTJ elements connected in series or parallel are arranged in correspondence with one MOS transistor (select transistor) formed in the surface region of a semiconductor substrate. In addition, the plurality of MTJ elements are stacked in a plurality of stages on one MOS transistor.
This technique is disclosed in detail in, e.g., patent reference 3 (Japanese Patent Application No. 2001-365236). According to this technique, a plurality of MTJ elements are stacked in a plurality of stages on one MOS transistor. This is convenient for increasing the memory capacity of the memory cell array.
In the techniques disclosed in patent references 1 and 2, a so-called destructive read operation principle is applied to read operation. As described in detail in these references, the destructive read operation principle has a problem that since read operation of one cycle basically comprises two read steps and two write steps, the read time is long.
To the contrary, in the technique disclosed in patent reference 3, the plurality of MTJ elements connected in series or parallel in a block have different resistance ratios. Hence, data of the plurality of MTJ elements in the block can be read out simultaneously by only one read step.
In the technique disclosed in patent reference 3, however, since the plurality of MTJ elements connected in series or parallel in a block must have different resistance ratios, the structure and manufacturing method of an MTJ element are complex. Additionally, since read data contains the data of the plurality of MTJ elements, an A/D conversion circuit or logic circuit which extracts the data of each MTJ element from the read data is necessary, resulting in a complex read circuit.
Still another example is a magnetic random access memory having a circuit structure as shown in FIG. 46 (e.g., patent reference 4 (Japanese Patent Application No. 2001-390549) and patent reference 5 (Japanese Patent Application No. 2001-390518)).
In a magnetic random access memory with such a circuit structure, assume that four MTJ elements (MTJ1, MTJ2, MTJ3, and MTJ4) 12 selected by a read word line RWL1 in, e.g., a lower left block BK11 are to be simultaneously read-accessed. The MTJ elements MTJ1, MTJ2, MTJ3, and MTJ4 form two complementary pairs.
In this circuit structure, assume that the same potential is biased to bit lines BL1, BL2, BL3, and BL4. In this case, the MTJ elements 12 in an unselected lower right block BLj1 make current paths between the bit lines BL1, BL2, BL3, and BL4. But no current flows between the bit lines BL1, BL2, BL3, and BL4, because their potentials are same. Hence, currents (solid lines) flowing to the MTJ elements MTJ1, MTJ2, MTJ3, and MTJ4 in the selected lower left block BK11 are read out by sense amplifiers 15-1, 15-2, 15-3, and 15-4, respectively.
However, if a potential difference is generated, a current flows through the MTJ elements 12 in an unselected lower right block BLj1. As the number of MTJ elements connected to each of the bit lines BL1, BL2, BL3, and BL4 increases, the current becomes large.
A select cell MOS transistor (column select switch 14-1) is inserted between the common line to the sense amplifiers 15-1, 15-2, 15-3, and 15-4 and the bit lines BL1, BL2, BL3, and BL4. Since the select MOS transistor has a resistance, a potential difference is generated in accordance with the resistance of the selected MTJ element. When the potential difference is generated between the bit lines BL1, BL2, BL3, and BL4, a current flows through the common node of the MTJ elements in the block.
For descriptive convenience, assume that the MTJ elements connected to the bit lines BL1, BL2, BL3, and BL4 have the same resistance value, only the MTJ element connected to the bit line BL1 is in a high-resistance state (the magnetizing directions of the storing layer and fixed layer are antiparallel), and the MTJ elements connected to the remaining bit lines BL2, BL3, and BL4 are in a low-resistance state (the magnetizing directions of the storing layer and fixed layer are parallel).
Let Is be the signal current difference when the MTJ elements are in the high- and low-resistance states, V be the bias voltage from the sense amplifier, Rm be the resistance of the MTJ element, Rt be the resistance of the MOS transistor of the block select switch, and Rc be the resistance of the MOS transistor of the column select switch. The signal current difference Is is given byIs=V/(Rt+Rc+Rm)−V/[Rt+Rc+Rm·(1+MR)]=MR×V/Rm÷[1+(Rt+Rc)/Rm]+[1+MR+(Rt+Rc)/Rm] (1)
A potential difference V between the bit line BL1 and the bit lines BL2, BL3, and BL4 due to the resistance of the MTJ element and that of the MOS transistor by data is given by V = V / [ Rt + Rc + Rm · ( 1 + MR ) ] × [ Rt + Rm · ( 1 + MR ) ] - V / [ Rt + Rc + Rm ] × [ Rt + Rm ] = MR × V × Rc / Rm ÷ [ 1 + ( Rt + Rc ) / Rm ] ÷ [ 1 + MR + ( Rt + Rc ) / Rm ] ( 2 )
Let n be the number of MTJ elements connected to a bit line BL. Then, a current
(three dotted lines in FIG. 46) which flows in a direction to cancel the signal current difference Is through the common terminal of the MTJ elements flows through a synthesized resistance in which the synthesized resistance of the three MTJ elements MTJ2, MTJ3, and MTJ4 arrayed in parallel and one MTJ element MTJ1 is in a n−1 parallel state. Hence, the currentis given by I = V [ ( Rm + Rm / 3 ) / ( n - 1 ) ] = V × ( n - 1 ) / ( 4 · Rm / 3 ) × Rc / Rm × MR ÷ [ 1 + ( Rt + Rc ) / Rm ] ÷ [ 1 + MR + ( Rt + Rc ) / Rm ] ( 3 )
From equations (1) to (3), the net signal current difference Is′ is given by Is ′ = Is - I = MR × V / Rm ÷ [ 1 + ( Rt + Rc ) / Rm ] ÷ [ 1 + MR + ( Rt + Rc ) / Rm ] × [ 1 - Rc · ( n - 1 ) / ( 4 · Rm / 3 ) ] ( 4 )
In equation (4), if the relationship 1−Rc·(n−1)/(4·Rm/3)>0, i.e., Rm/Rc>4(n−1)/3 is not satisfied, a read error occurs.
To prevent the read error, the resistance Rm of the MTJ element must be increased, the channel width of the MOS transistor of the column select switch must be increased, or the number of cells connected to the bit line BL must be decreased.
However, if the number of cell arrays is simply increased while decreasing the number of cells connected to the bit line BL due to the constraint on the maximum number of cells connectable to the bit line BL, the chip size increases, and it may be impossible to sufficiently increase the integration density of MTJ elements. For this reason, the above measures can hardly be taken for a large-capacity memory. | {
"pile_set_name": "USPTO Backgrounds"
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Computing devices such as personal computers, game consoles, smart phones, and the like often utilize a time-consuming process in order to load and cache pages used by applications into memory. The pages are typically stored on a rotating non-volatile media such as a magnetic hard disk (e.g., a hard drive). However, the device's processor executes instructions only from addressable memory such as DRAM or some other type of volatile electronic memory. The operating systems used in the computing devices cache the pages used by applications in memory so that the applications do not need to load pages from the rotating media as frequently.
The transfer of the pages from the hard drive is slow, particularly when the application is loading a large file. This is also prevalent in restoring the computer system from hibernate mode. A significant factor in the transfer time is due to the disk drive spin up speed. A relatively small disk spinning at a relatively slow RPM requires 5 to 6 seconds to spin up and be usable. Larger disks such as multi-platter devices and those spinning at faster RPMs require 10 to 12 seconds or more to spin up.
This problem gets worse as applications grow in size to incorporate security fixes and become more reliable. These applications often require more memory to operate without having to continually transfer data to and from the rotating storage media. However, upgrading the memory of machines is often too costly to undertake for corporations and end users or is beyond the skill level of individual users. Although the cost of memory itself is low, the labor and downtime involved in physically opening each machine and adding RAM may cost several hundred dollars.
Another problem where upgrading the memory of machines is often too costly to undertake is when a system is required to occasionally execute larger and more complex applications than normal. For example, an accounting staff of a company might need to run consolidation applications a few times a month. The larger and more complex applications require more memory to operate efficiently. Although the cost of memory itself is low, the labor and downtime involved in physically opening each machine and adding RAM may cost several hundred dollars. This cost may not justify the additional memory for the few times the application is run. | {
"pile_set_name": "USPTO Backgrounds"
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In my above identified patent application there is described an improved process for drying and pelletizing sewage sludge to form pellets of small and uniform sizes. Such pellets then are suitable for use as a soil conditioner, or as a fuel. While it has been known for many years that sewage sludge could be pelletized and could be used as a fuel or soil conditioner, production of pellets in uniform sizes was not achieved prior to my invention.
In my sludge treatment process, dewatered sludge cake was mixed with a previously pelletized sludge particles and passed through a dryer. The particles of previously dried sludge assist in pelletizing the sludge cake by forming a nucleus for the formation of the pellets. The exiting materials then are separated from the of gas stream and clarified. Fines are removed and conveyed to a recycle bin. Pellets of the desired size are separated and routed to storage for shipment or sale. Oversized particles are routed to a crusher and crushed. The crushed particles are then mixed with the fines and recycled with the incoming dewatered sludge cake. In this way, the product produced for sale, is constituted only of pellets of uniform size and does not contain oversized particles or fines.
While the process requires the use of a fuel for drying the sludge cake mixture, as described in my application, the fuel could be a fossil fuel, or coal or waste wood chips or the like, or a mixture. While the fuel could present a major expense, in many municipalities, there is no alternative means to dispose of sewage sludge.
One unacceptable alternative in many municipalities is the dumping of the sludge in a nearby river. Obviously, federal regulations now prohibit such practices. Another alternative would be to dispose of the sludge in a landfill. However, in the case of many municipalities, landfill capacity is either not present or will not be in the predictable future.
In addition to sewage sludge, in many municipalities the municipal water must also be treated to "soften" it for distribution. In many municipalities the water source contains excessive concentrations of calcium and magnesium salts. Such "hard" water requires excessive quantities of soap, and leave scum which many stain fabrics. It is desirable then to treat the water to remove these calcium and magnesium salts before distribution.
A common water treatment process involves the addition of lime, or lime and soda ash, to precipitate the calcium and magnesium salts as calcium carbonate and magnesium hydroxide. This process however results in a by-product called lime sludge which also presents a disposal problem. Typically, the lime sludge is initially treated to remove the magnesium hydroxide and then is recalcined to regenerate lime from the sludge for reuse in the water treatment process. This then minimizes the disposal problem relative to water treatment.
Recalcination, is typically carried out at temperatures of 1600.degree.-1800.degree. F. and produces off gases at 300.degree.-350.degree.. This then also produces a requirement for fuel in a situation wherein alternate disposal means are not available. | {
"pile_set_name": "USPTO Backgrounds"
} |
The goal of timing-driven layout, such as floorplanning, placement, wiring, etc., is to perform the layout design process such that the design satisfies the particular timing constraints specified by the designer. In the most general case, the timing constraint information is specified to the timing-driven layout tools in the form of arrival times for signals at the inputs of the design, and required arrival times for signals at the outputs of the design.
Timing-driven design tools generally deal with timing constraints in one of three ways or some variation thereof, namely, basing the design on path delay, net weight, or net delay. A net is an electrical connection of physical pins and/or logical input/output ports of electronic components.
Path delay based tools consider timing constraints on specified timing paths in the design, and perform the design process so as to satisfy these constraints. The constraints are generally in the form of maximum and/or minimum resistance-capacitance (RC) delay through a path. Theoretically, a timing constraint could be specified for every input-output path in the design. However, the number of such paths increases exponentially with the size of the design and, in practice, only a limited subset of paths can be effectively processed by conventional timing-driven tools. Thus, for large designs, it is impractical to monitor all paths in a design during the design process. In this regard, the cost can be reduced by monitoring a subgraph of the design containing several paths rather than monitoring the individual paths.
Net weight based methods consider weight factors for the nets. These weight factors indicate the relative importance of each net with respect to timing. Net weight based methods attempt to shorten nets having higher weights, thus reducing their delay, at the expense of other nets with lower weights. However, net weight based methods cannot guarantee meeting the overall timing constraints and, generally, must be run several times, adjusting the net weights with each run, in order to converge on the required timing for a particular design.
Net delay based tools consider targets, namely, resistance (R), capacitance (C) and resistance-capacitance (RC), on individual nets in the design and perform the design process so as to satisfy these targets. Typically, the individual net targets are generated based on the overall design constraints such that if every net target is met, the overall design will meet the timing goals. Net delay based approaches are able to monitor all nets in a design during the design process with relatively low computation cost. However, the effectiveness of the tool hinges on how the net targets are generated.
Existing target generation approaches apportion the delay specified on a path, which consists of several nets, as individual RC delay targets on the constituent nets. Generally, conventional target generation approaches follow the basic principles of target generation, but each may differ with respect to variations on the set of timing paths generated, and the way in which the delay on a path is apportioned to its constituent nets. See, for example, W. K. Luk, "A Fast Physical Constraint Generator for Timing Driven Layout", 28th ACM/IEEE Design Automation Conference, Paper 37.3, June 1991, pp. 626-631 ("the Luk paper"); and H. Youssef and E. Shragowitz, "Timing Constraints for Correct Performance", Proc. ICCAD, November 1990, pp. 24-27 ("the Youssef and Shragowitz paper").
In accordance with conventional target generation approaches, the input is the timing constraints on the design, and the output is the targets on the nets. Typically, the procedure begins by setting all initial targets on all nets to zero, and then proceeding with the following steps:
1. Run timing analysis on the logic network. This step takes into account the targets generated in the previous iteration of the repeat loop, and generates (i) a set of timing paths (each consisting of a sequence of timing nodes), and (ii) a slack value for each path. Slack is the amount of delay that can be added to a path without affecting the performance of the design;
2. Apportion the slack values on the paths to the nets contained in these paths. This step is carried out differently in different target generation approaches. In general, this step takes into account information such as existing targets on the nets, loading on the nets due to the cells they are connected to, the sensitivity of the net delays to changes in capacitance and resistance, etc.; and
3. Repeat steps 1 and 2 until all path slacks are zero or sufficiently near zero. In practice there may be an upper bound on the number of iterations after which the algorithm must exit. The targets on the nets thus generated are then passed on to placement/wiring programs.
Explained in another way, in essence, conventional target generation processes transform timing constraints on a design into timing constraints on the nets within the design, where the cells that are connected together by the nets are fixed predesigned entities (library cells or standard cells) that have known delays. This is illustrated in FIG. 1 which shows one critical path through a chip 10 from an input pin P1 to an output pin P2. The path is made up of six nets, n1-n6, and five standard cells, c1-c5. Assuming that there is a positive slack S on this path as determined by timing analysis, i.e., S units of delay can be added to this path without affecting the performance of the design, the target generation algorithms apportion the slack value S among the nets n1-n6, and accordingly modify the R, C and RC targets on these nets to reflect this apportionment. Note that this is a simple example with a single critical timing path. In general, there are many critical timing paths that intersect each other, and the targets assigned to a given net must be based on the slacks on all the timing paths to which it belongs.
Thus, conventional approaches for target generation work with "flat" designs in which the cells that the paths pass through are predesigned entities with fixed delays. However, in so-called multilevel hierarchical circuit designs, this condition may not hold since the cells themselves are made up of hierarchical entities whose internals have not yet been designed. Generally, a multilevel hierarchical circuit design refers to an electronic design whose representation has a containment hierarchy, i.e., the entire design is made up of a cell, which in turn contains child cells connected to each other by nets. Each cell is either a standard cell, which means that it is a predesigned cell taken from a standard cell library, or a macro cell, which means it contains one or more child cells. The children of macro cells may be standard cells or themselves macro cells. The current hierachy level refers to the particular level of design hierarchy at which the physical design is being carried out at a given time.
Referring to FIG. 2, in a multilevel hierarchical circuit design, there may be several levels of hierarchy between the top level entity of a design hierarchy, for example, chip 12, and the predesigned leaf level entities, for example, standard or library cells c6-c9, for which delay models are available. Thus, the top level entity or chip 12 of the hierarchy can be made up of macro cells, m1 and m2, that have not yet been designed. The lower-level cells c6-c9 (which may be standard cells or macro cells themselves) within the macro cells m1,m2 have not been placed and wired, and hence there are no fixed timing models available for the macro cells m1,m2. In order to use conventional techniques of target generation on the design of FIG. 2, the hierarchy would have to be "flattened", i.e., the boundaries of the hierarchical macro cells m1,m2 would have to be removed. Target generation could then be carried out on the flattened design to derive targets on the nets.
Existing target generation approaches described above cannot be used on multilevel hierarchical circuit design for several reasons, as follows:
1. Conventional target generation approaches assume that each cell in the design is a predesigned standard cell with fixed timing properties;
2. Even if target generation was carried out using conventional target generation on the flattened design, i.e., with the macro cell boundaries removed, the resulting net targets would not be directly useful. Specifically, the target assigned to any wire that crosses a macro cell boundary would still have to be apportioned to the two subnets, one outside and one inside the macro cell, because only the former is visible to a hierarchical floorplanner when it is working on the upper level of the hierarchy. For example, nets n7 and n8 in the hierarchical design illustrated in FIG. 2.
3. The floorplanning process being utilized would generally result in a layout in which nets within a macro cell have lower average length than nets crossing macro boundaries. Existing target generation approaches working on the "flattened" design would not take advantage of this to proportionately distribute wire delays.
Another disadvantage is that such flattening defeats the purpose of hierarchical design and requires the whole flattened design to be processed at once, which requires prohibitive amounts of memory and computation time for large designs. Further, in using this flattening approach, all nets are given equal weightage in "apportioning" delays among them, thus "local" nets, within macros such as m1, that have a lower average length cannot be distinguished from "global" nets across the whole chip that have a higher average length.
Accordingly, an improved target generation approach is required, particularly for multilevel hierarchical circuit designs. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a recording apparatus in which recording is performed by ejecting ink to fly in the form of small droplets through ejection ports (orifices) and depositing the small droplets on the surface of a recording material, as well as a method of controlling the recording apparatus.
2. Description of the Related Art
Heretofore, as ink for ink jet recording, water-based ink has been primarily employed from the standpoints of, e.g., ensuring safety and eliminating a bad odor. There are known many types of ink prepared by dissolving or dispersing various water-soluble dyes or pigments in water or a mixture of water and a water-soluble organic solvent, and if necessary adding a moisture retaining agent, a dye dissolving aid, a fungicide, etc. Ink jet recording made using such ink has been rapidly developed in these years because of many advantages of, e.g., enabling high-speed recording to be easily realized as several thousands or more ink droplets can be ejected per second, generating less noise, ensuring easy production of a color image, providing a high resolution, and permitting an image to be printed on plain paper.
Further, with a recent trend toward the lower price, higher performance, and standardization of the GUI (Graphical User Interface) environment in the field of personal computers, there is increasing demand for better color development, higher quality, higher durability, higher resolution and higher speed in image recording using printers or the like. To meet such a demand, technical concepts have been proposed with an aim at holding down feathering, bleeding (color mixing) and other unfavorable properties by leaving color components as much as possible on the.paper surface and making the edges of recording dots sharper.
As the first example, Japanese Patent Laid-Open No. 58-13675 discloses a method of controlling absorption of ink and spread of recording dots into and over paper by addition of polyvinyl pyrrolidone into the ink. As the second example, Japanese Patent Laid-Open No. 3-172362 discloses a method of controlling absorption of ink and spread of recording dots into and over paper by addition of a specific micro-emulsion into the ink.
As the third example utilizing a sol-gel transition phenomenon of ink, Japanese Patent Laid-Open No. 62-181372, and No. 1-272623, as well as others disclose that ink can be prevented from permeating into paper by using an ink which is in the gel form at room temperature and transitions to the sol form upon heating, and recording an image with the ink applied in the sol state to a recording material, because the ink restores to the gel state upon cooling.
As the more recent fourth example, Japanese Patent Laid-Open No. 6-49399 discloses an ink which is added with a compound having a characteristic of thermally gelling in a reversible manner, thereby realizing good color development and fixing property, showing less feathering, and being superior in preservation and reliability of prints, as well as an ink jet recording method and apparatus both using the ink. The technical background of this related art is based on a phenomenon that as a solution of a particular water-soluble high molecule is gradually heated, water solubility of the high molecule is reduced and the solution becomes cloudy at a specific temperature (that is called a clouding point). Typical examples of such a high molecule include, for example, N-isopropyl acrylic amide, polyvinyl methyl ether, polyethylene oxide, and hydroxypropyl cellulose. Because these high molecules show solubility having a negative temperature coefficient, they are separated and precipitated from the solution at temperatures not less than the clouding point. In the precipitating state, viscosity of the solution is lowered due to generation of hydrophobic microgel. After being recorded on a recording material in the precipitating state, the solution restores its original viscosity with a temperature effect developed on the surface of the recording material. Thus, the increased viscosity holds down the ink from permeating into paper.
Meanwhile, as the fifth example, M. Croucher et al. point out the problems of conventional homogeneous ink and propose, as inkjet ink in future, an inhomogeneous ink utilizing latex (see M. D. Croucher and M. L. Hair; Ind. Eng. Chem. Res. 1989, 28, 1712-1718, "Design Criteria and Future Direction in Inkjet Ink Technology"). In addition, U.S. Pat. No. 4,246,154 discloses an ink wherein fine particles of a vinyl polymer colored with dyes are stabilized in the anionic form. U.S. Pat. No. 4,680,332 discloses an inhomogeneous ink containing an oil-soluble dye wherein a water-soluble polymer coupled to a non-ionic stabilizer is dispersed a liquid medium. Also, U.S. Pat. No. 5,100,471 proposes a water-based ink consisted of a solvent and colored particles each made up of a polymer core and a silica shell covalently bonded to a dye. This proposed ink has features of enabling colors to develop more sharply on paper, being stable against temperature, and providing high water-resistance.
Further, as the sixth example, Japanese Patent Laid-Open No. 3-240586 proposes a non-water-based ink wherein colored particles covered by a resin swelling with a dispersion medium, such as kerosene, are dispersed in the dispersion medium. It is suggested that this proposed ink is effective particularly in preventing feathering of ink images and clogging of nozzles for ejecting liquid droplets.
The above-stated first and second examples have a problem in fixing property because the ink is prevented from permeating into paper and is to left stand on the paper for a long time without undergoing permeation. Another problem is that there occurs mixing between different colors (i.e., bleeding).
The sol-gel transition ink shown as the third example has a problem that a recorded image may suffer from bleeding and transfer fouling because changes in preservation temperature of prints cause the ink to have fluidity and to flow out.
The ink added with a compound having a characteristic of thermally gelling in a reversible manner, shown as the fourth example, is not suitable for a method of recording an image at such a high speed of not more than 10 msec per pixel as required in ink jet recording, because a rise in viscosity with a temperature drop is too slow as a result of employing water-soluble cellulose ethers. Also, when used in ink jet recording, ink is required to have an upper limit of viscosity not more than 20 mPa.multidot.s at the time of ink ejection. The ink must be therefore employed with a low concentration enough to satisfy the above requirement, which makes it hard for the ink to produce the effect of increasing viscosity sufficiently.
On the other hand, of the fifth example group, the ink containing vinyl polymer fine particles stabilized in the anionic form has a problem that a pH range in which the ink can disperse stably is narrow and a selectable range of dyes is small consequently. Another drawback is that spread of recording dots on paper is too small to provide a satisfactory value of optical density (O.D.). Further, the ink is less effective in shortening a fixing time, though this effect is essential for high-speed recording, because a fixing mechanism of the ink depends on only evaporation and permeation as with conventional image forming means.
Another ink of the fifth example group, which contains an oil-soluble dye and in which a water-soluble polymer coupled to a non-ionic stabilizer is dispersed a liquid medium, has an enlarged selectable range of dyes, but is also less effective in shortening a fixing time because a fixing mechanism of the ink depends on only evaporation and permeation as with the above ink. In addition, this ink is disadvantageous in preventing mixing between different colors (i.e., bleeding) because it takes time until adjacent dots are fixed into a stable state.
Still another disperse ink having the polymer-core/silica-shell structure is superior in stability of pigment dispersion, but cannot provide a satisfactory value of O.D. because the ink has no special means for causing a color material to aggregate on the paper surface. Further, this ink is also less effective in shortening a fixing time because its fixing mechanism depends on only evaporation and permeation, thus accompanying a problem of bleeding.
The problem common to the above three types of ink of the fifth example group is that a recorded image has a poor abrasion property as a result of taking no account about adhesion of color material particles onto the paper surface.
The ink of the sixth example is problematic in points of safety, a bad odor and so on because kerosene is used as the dispersion medium.
Physical properties required for water-based ink, in particular, required for ejecting the ink in the form of small droplets for ink jet recording will be now explained below. The physical properties required for inkjet ink to be ejected in the form of small droplets are given by;
surface tension; >20 dyne/cm (relating to a refill speed), PA1 viscosity; 1-20 mpa.multidot.s, PA1 pH: 3-10, and PA1 fixing time<20 sec (preferably as short as possible).
Here consider transition of ink onto paper. Generally, there is known the Lucas-Washburn's equation about a transition phenomenon of a liquid onto paper. Assuming that the amount of the liquid transited is V, the index of paper roughness is Vr, the absorption coefficient is Ka, the transition time is T, and the wetting start time is Tw, the Lucas-Washburn's equation is expressed by the following formula (1) when the liquid is water:
V=Vr+KaT-Tw (1)
In the formula (1), Ka relates to physical properties of both paper and ink, and is expressed by the following formula (2): ##EQU1##
In the formula (2), r is the diameter of a capillary, .gamma. is the surface tension of the liquid, .theta. is the contact angle, and .eta. is the viscosity of the liquid.
As is apparent from the formula (1), to leave a color material on the paper surface, it is required to slow down permeation of a liquid, i.e., to reduce the absorption coefficient Ka (the evaporation time can be prolonged by reducing Ka). It is also apparent that, to the above end, physical properties of ink preferably have a smaller surface tension, a larger viscosity and a larger contact angle. But since there are restrictions in those physical properties of ink for ink jet recording, adjustment of Ka is not easy.
On the other hand, where the liquid is a non-aqueous solvent, e.g., ethanol, the wetting time Tw in the formula (1) can be ignored and therefore the fixing time can be shortened. However, since the absorption coefficient Ka is increased to promote an effect of permeating ink, a printed image is more susceptible to feathering. Further, since the term of cos.theta. in the formula (2) is determined depending on a combination of ink and paper, image quality depends on the types of paper. Thus, the ink using a non-aqueous solvent cannot satisfy a paper selection property.
The above-mentioned problems are believed to possibly occur also in conventional color-material dispersed ink so long as image formation depends on only evaporation and permeation.
With a view of solving the problems mentioned above, the inventors previously proposed it to use an ink for printing which contains a high molecule having viscosity that increases in a thermally reversible manner (Japanese Patent Laid-Open No. 8-333535).
Taking into account the above-stated restrictions being attributable to the fact that ink is a liquid in the homogenous state of a color material and a solvent regardless of temperature, the inventors proposed in the above Japanese Patent Application an ink which causes a state change triggered depending on temperature so that the color material and the solvent separately behave on a recording material.
To explain the state change in more detail, high molecule particles are isolatedly dissolved in the ink state at room temperature, but they aggregate at temperature higher than a certain value into a dense liquid having a high viscosity, and form a state where the color material is coupled to the high molecule. By applying the ink in the latter state to the recording material, recording is made with a dense color material phase left on the surface of the recording material, while a thin solvent phase permeates into the recording material. Also, the state change must be reversible to be adapted for a wide range of environment temperature under which recording is potentially made.
In practice, when small droplets of ink are ejected from a recording head, it is advantageous for high-speed recording that the ink has a low viscosity. A phenomenon of the above state change can be therefore realized by ejecting the ink in the state having a low viscosity in operation of the recording head, and recording the ink on a recording material heated up to above the transition temperature. Owing to the relationship of temperature of the ink droplets<temperature of the recording material in the above case, at the moment the ink droplets adhere to the surface of the recording material, the surface of the recording material is cooled to provide a slight time lag in rising of the ink droplet temperature up to the transition temperature. During the lag time until reaching the transition temperature and showing a high viscosity, the ink droplets have a low viscosity and therefore the ink permeates into the recording material in accordance with the Lucas-Washburn's equation. This mechanism also serves as means for solving a problem that if the color material is all left on the surface of the recording material, a recorded image would have a poor abrasion property.
The transition temperature is preferably set to be higher than the environment temperature (room temperature) under which recording apparatus is usually employed, and to fall in the range of 35.degree. C. to 100.degree. C. to enhance the effect of increasing viscosity depending on temperature (i.e., to enlarge a temperature difference between before and after the state change). The transition temperature equal to 100.degree. C. or higher is not preferable because it would cause a notable increase in viscosity due to evaporation of water in the ink. As shown in a viscosity characteristic graph of FIG. 1, by way of example, the ink preferably has the transition temperature in the range of 46.degree. C. to 48.degree. C.
Meanwhile, as a method of ejecting ink for recording, there is known an ink jet type applying thermal energy to the ink and causing ink droplets to fly out through orifices. In such an ink jet method, a bubble is generated in the ink with the applied thermal energy, whereupon the ink droplets are given kinetic energy enough to eject through the orifices. When ejecting the above-proposed ink by the ink jet method, heating the average temperature of the ejected ink droplets up to the transition temperature is more efficient as a heating method than heating paper separately. However, when such an ink as requiring much heat to be applied for ejection, like the above-proposed ink, is ejected, the conventional heating method may not impart sufficient thermal energy to the ink. In some cases, before sufficient thermal energy Is transmitted to the ink, a bubble is abruptly generated and the ink is thermally isolated from a heater.
To solve the above problem, therefore, the inventors proposed a driving method for averaging heat flux transmitted from the heater surface to the ink in a controlled manner. As one example of such a driving method, the inventors showed a method of heating and ejecting the ink by using a train of five pulses. In that example, the driving voltage was set to 7.5 V (this voltage value itself has no direct meaning in relation to the actual process and is merely one instance because the amount of heat actually generated varies in the resistance value of a heater; that is, what has actual meaning is a value of heat flux explained below). As shown in FIG. 27, the ink was heated by a train of five pulses each having a crest value of 7.5 V.
In the above example, as shown in FIG. 28, heat flux was produced in the form of a pulse train corresponding to the driving voltage. A peak value of heat flux produced upon application of the driving voltage exceeded 100 [MW/m.sup.2 ] and, particularly, it rose to 140 [MW/m.sup.2 ] at the time a bubble was generated. This enabled the bubble to stably generate in volume sufficient to provide a strong ejection force even with the above-proposed ink. Also, as shown in FIG. 29, the ink being 10 .mu.m over the heater surface was heated up to 69.6.degree. C. until generation of a bubble. Thus, an effect of sufficiently heating the ink to be ejected was achieved.
The driving method of generating one bubble with a plurality of driving signals as stated above, however, is inconvenient in the case of ejecting ink through a number of nozzles. Although a printing head usually has a number of nozzles for realizing high-speed printing, a load imposed on a power supply is remarkably increased if heaters for those nozzles are energized at the same time. In the technical field of ink jet recording and thermal transfer recording, therefore, a block driving method has been widely used for the purposes of reducing the load imposed on the power supply and realizing high-speed printing. With the block driving method, the nozzles are divided into a plurality of blocks which are energized with a small time lag therebetween, and arrangement of the nozzles is shifted to eject ink in proper sequence so that the printing result is not affected.
Where a pulse for driving one nozzle is given by a single pulse, or where, though it consists of a plurality of pulses, these pulses have so short time intervals as to be virtually regarded as a single pulse, the above block driving method does not accompany a notable difficulty. For example, when 64 nozzles are divided into 8 blocks each comprising 8 nozzles and each nozzle is driven by a pulse of 3 .mu.s, respective first nozzles of the 8 blocks are driven at the same time, and after several .mu.s, respective second nozzles of the 8 blocks are driven at the same time. Subsequently, respective third to eighth nozzles of the 8 blocks are all driven in a like manner. This makes it possible to drive all the nozzles in a shatter time, alleviate a shift in printing, and reduce the load imposed on the power supply upon simultaneous driving.
Where a driving pulse applied to one nozzle is given by a train of five pulses and the time intervals between the five pulses are predetermined like the above-explained example, however, it is difficult to freely apply the block driving method. As one example for applying the driving signals, which is not the known art, but taken into account in studies made for accomplishing the present invention, FIG. 30 shows a pulse train consisted of three pre-pulses (for preheating) each having a width of 1 .mu.s and a driving pulse proper (pulse for generating a bubble directly) having a width of 3 .mu.s, with intervals between the pulses being each 7 .mu.s. The illustrated example is to drive a nozzle array comprising 8 blocks. In the block driving method, it is preferable from the standpoint of causing no shifts in a recorded image that driving of all the blocks is completed as quick as possible. To this end, therefore, the block driving method is required to be executed such that the first signal of the second block, for example, locates between the first and second signal of the first block. In the example of FIG. 30, the driving signals of the second block are issued with a delay of 1 .mu.s from the driving signals of the first block, the driving signals of the third block are issued with a delay of 1 .mu.s from the driving signals of the second block, and so on. The driving signals of the eighth block are finally issued with a delay of 1 .mu.s from the driving signals of the seventh block.
In the illustrated example, because the driving signals of the respective blocks are shifted 1 .mu.s from one another, the preheating pulses each having a width of 1 .mu.s are not overlapped. But the driving pulse has a width of 3 .mu.s, and therefore the driving pulse of the first block overlaps with the driving pulse of the second block for a period of 2 .mu.s. During this period, a current value is doubled and a power supply requires a current capacity twice as much. In the illustrated example, because the driving pulse of the third block further overlaps with the driving pulses of the first and second blocks, the power supply actually requires a current capacity triple as much. If the respective blocks are driven with a time lag of 3 .mu.m therebetween to prevent the driving pulses from overlapping with each other, overlaps between the driving pulses are avoided, but the driving pulse of the first block overlaps with the third preheating pulse of the fourth block and subsequently the second preheating pulse of the seventh block. Accordingly, the power supply requires a current capacity twice as much for a period of 2 .mu.s. | {
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Conventionally, in a case where data transmission is performed through near field communication, generally, a processing request is issued from a master device to a slave device. In TransferJet (trademark) that is one of near field communication technologies, priority levels of devices are determined based on modes at the time of waiting for a connection. When a device waiting as a master is connected to a device waiting as a slave, a connection can be established between the master device having a high priority level and the slave device having a low priority level. In addition, a device having a dynamic mode at the time of connection waiting determines a priority level of the device in accordance with a partner device such that the device has a low priority level in a case where the partner device is a master, and the device has a high priority level in a case where the partner device is a slave.
However, in the conventional technology, in a case where master devices each having a file transmission request or dynamic devices approach each other, a determination of which one is a high-priority device cannot be made, a connection cannot be established, and a conflict occurs. Accordingly, a communication function using an OBEX (Object Exchange) protocol or the like cannot be operated between devices having the same mode. | {
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1. Field
The present disclosure relates to air seeder boots and more particularly pertains to a new method and apparatus for improving an air seeder boot to provide greater durability to the mounting of the air seeder boot on the air seeder apparatus.
2. Description of the Prior Art
Air seeder apparatus are used to move seed for planting from a bin of seeds to a furrow formed in the ground for the purpose of planting the seed for growing crop. The air seeder apparatus includes a seed boot for each row that the air seeder apparatus is capable of planting in one pass of the apparatus across the field. The seed boot includes a passage or channel through which the seed is moved from the seed supply container to the furrow. The bottom end of the seed boot is positioned in close proximity to the ground and the furrow, and is subject to contact with the ground that places stress on the structure mounting the boot to the base mount of the apparatus. The seed boot may be connected to the base mount by a pin, such as a bolt fastener, that passes through ears or tabs that extend from the base mount and the seed boot. The fastener passes through holes in the ears to hold the boot to the base mount, with some degree of pivot movement of the boot being possible. FIG. 1 of the drawings provides an illustration of the prior structure.
Due to the forces applied to the boot by contact with the ground, the mount is subject to significant wear over a planting season. The seed boot may be easily removed from and replaced on the air seeder apparatus, but this can be expensive, and rebuilding the mount structure on the main seeder apparatus is not as easily accomplished and thus presents a greater challenge. | {
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A fiber array spectral translator (“FAST”) system when used in conjunction with a photon detector allows massively parallel acquisition of full-spectral images. A FAST system can provide rapid real-time analysis for quick detection, classification, identification, and visualization of the sample. The FAST technology can acquire a few to thousands of full spectral range, spatially resolved spectra simultaneously. A typical FAST array contains multiple optical fibers that may be arranged in a two-dimensional array on one end and a one dimensional (i.e., linear) array on the other end. The linear array is useful for interfacing with a photon detector, such as a charge-coupled device (“CCD”). The two-dimensional array end of the FAST is typically positioned to receive photons from a sample. The photons from the sample may be, for example, emitted by the sample, reflected off of the sample, refracted by the sample, fluoresce from the sample, or scattered by the sample. The scattered photons may be Raman photons.
In a FAST spectrographic system, photons incident to the two-dimensional end of the FAST may be focused so that a spectroscopic image of the sample is conveyed onto the two-dimensional array of optical fibers. The two-dimensional array of optical fibers may be drawn into a one-dimensional distal array with, for example, serpentine ordering. The one-dimensional fiber stack may be operatively coupled to an imaging spectrograph of a photon detector, such as a charge-coupled device so as to apply the photons received at the two-dimensional end of the FAST to the detector rows of the photon detector.
One advantage of this type of apparatus over other spectroscopic apparatus is speed of analysis. A complete spectroscopic imaging data set can be acquired in the amount of time it takes to generate a single spectrum from a given material. Additionally, the FAST can be implemented with multiple detectors. The FAST system allows for massively parallel acquisition of full-spectral images. A FAST fiber bundle may feed optical information from its two-dimensional non-linear imaging end (which can be in any non-linear configuration, e.g., circular, square, rectangular, etc.) to its one-dimensional linear distal end input into the photon detector.
A problem exists with the prior art's use of a FAST system. The linear array end of the FAST, when input into a photon detector, may become slightly misaligned so that an image produced may be shifted due to the misalignment. Furthermore, the peaks in a spectrum of the sample may not be aligned with the peaks of a known calibrated sample of the same substance and therefore the received peaks may not be calibrated. Additionally, the fibers in the FAST may not allow for a resolution of the resulting image to a degree necessary. The present disclosure, as described herein below, presents methods and systems for overcoming these deficiencies in the prior art.
The combination of calibration and reconstruction methods according to one embodiment of the present disclosure may be useful among fiber optics imaging manufacturers. The calibration and image reconstruction approaches discussed herein are independent of any specific FAST-based imaging applications. Accordingly, it is an object of the present disclosure to provide a method for spectral calibration, comprising obtaining a first image of a known substance using a photon detector and a fiber array spectral translator having plural fibers, wherein said first image comprises at least one pixel; providing a second image of said substance wherein said second image comprises at least one pixel; comparing said first image with said second image; and adjusting at least one pixel of said first image based on said comparison of images to thereby obtain an adjusted image. It is another object of the present disclosure to additionally obtain a first spectrum of said substance from one of said plural fibers wherein said first spectrum comprises at least one peak; provide a second spectrum of said substance wherein said second spectrum comprises at least one peak; compare at least one peak of said first spectrum to at least one peak of said second spectrum; and adjust said first spectrum based on said comparison of peaks.
It is yet another object of the present disclosure to provide a method for spectral calibration, comprising: obtaining a first data set representative of a first image of a known substance, wherein said first data set is obtained using a photon detector and a fiber array spectral translator having plural fibers; providing a second data set representative of a second image of said substance; comparing said first data set with said second data set; and adjusting said first data set based on said comparison of said first and second data sets. It is still another object of the present disclosure to additionally obtain a third data set representative of a first spectrum of said substance from one of said plural fibers wherein said first spectrum comprises at least one peak; provide a fourth data set representative of a second spectrum of said substance wherein said second spectrum comprises at least one peak; compare a part of said third data set representative of at least one peak of said first spectrum to a part of said fourth data set representative of at least one peak of said second spectrum; and adjust said first data set based on said comparison of said third and fourth data sets.
It is a further object of the present disclosure to provide a method for spectral calibration comprising: obtaining a first image of a known substance using a photon detector and a fiber array spectral translator having plural fibers, wherein said first image comprises at least one pixel; providing a second image of said substance wherein said second image comprises at least one pixel; obtaining a first spectrum of said substance from one of said plural fibers wherein said first spectrum comprises at least one peak; providing a second spectrum of said substance wherein said second spectrum comprises at least one peak; comparing said first image with said second image to thereby obtain a bulk shift adjustment; and comparing at least one peak of said first spectrum to at least one peak of said second spectrum to thereby obtain a subpixel adjustment.
It is yet a further object of the present disclosure to provide a method for spectral calibration, comprising: obtaining a first data set representative of a first image of a known substance using a photon detector and a fiber array spectral translator having plural fibers, wherein said first image comprises at least one pixel; providing a second data set representative of a second image of said substance, wherein said second image comprises at least one pixel; obtaining a third data set representative of a first spectrum of said substance from one of said plural fibers wherein said first spectrum comprises at least one peak; providing a fourth data set representative of a second spectrum of said substance wherein said second spectrum comprises at least one peak; comparing said first data set with said second data set to thereby obtain a bulk shift adjustment; and comparing said third data set with said fourth data set to thereby obtain a subpixel adjustment.
It is still a further object of the present disclosure to provide a system for spectral calibration of a known substance, comprising: a photon source for illuminating said substance with first photons to thereby produce second photons; a fiber array spectral translator having plural fibers, wherein said fiber array spectral translator receives said second photons; a photon detector operatively connected to said fiber array spectral translator, wherein said photon detector detects said second photons; a memory unit comprising a first data set representative of a first image of said substance; and a microprocessor unit operatively connected to said photon detector and said memory unit, wherein said microprocessor obtains a second data set from said second photons, compares said first and second data sets, and adjusts said first data set based on said comparison. It is yet still a further object of the present disclosure to further provide a display device operatively connected to said microprocessor unit so as to display an image selected from the group consisting of: said first image, a second image representative of said second data set, an adjusted image representative of said adjusted first data set, and combinations thereof. | {
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1. Field
One or more aspects of embodiments of the present invention relate to secondary batteries.
2. Description of the Related Art
Secondary batteries are rechargeable, and thus are economical and environmentally friendly. As such, secondary batteries are used in a variety of electronic devices, and the design of such electronic devices plays a role in their utility.
For example, various wearable computer devices that use secondary battery as a power source, as well as ergonomic cell phones and laptop computers, include curved areas. Accordingly, secondary batteries included in such electronic devices need to have curved areas to match the curved areas of the electronic devices. | {
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1. Field of the Invention
This invention relates to a liquid coating machine of a rotary screen printing press or the like.
2. Description of the Related Art
In screen printing by a rotary screen printing press, ink is placed in a screen printing forme, and the screen printing forme is pressed against paper by a squeegee or a doctor roller to transfer the ink to a printing surface of the paper through the openings of the screen printing forme. The screen printing forme needs to be replaced each time a different printing product is to be printed.
The work of replacing the screen printing forme will be described, for example, in connection with an intaglio and rotary screen printing press as shown in FIG. 6.
In this printing press (liquid coating machine), sheets of paper (sheets, for short) W are fed one by one from a feeder 10 onto a feedboard 11. Then, the sheet W is passed from a swing arm shaft pregripper 12 on to a transfer cylinder 13, and then gripped by grippers 14a of an impression cylinder 14 for the purpose of transport (transport means). On the other hand, conventional inks are supplied from within ink fountains 20 to chablon rollers 17 via ink fountain rollers 19 and intermediate rollers 18, and supplied to an ink collecting cylinder 16 (other device). Then, the inks are collectively supplied to an intaglio plate of a plate cylinder 15. Also, special ink is directly supplied, in a constant amount in a predetermined pattern, from within a rotary screen cylinder (stencil printing cylinder) 22 to the intaglio plate of the plate cylinder 15 via a rubber roller 21 (liquid coating unit).
These inks have their surplus amounts removed by a wiping roller 23, and are then transferred to the sheet W passed on to the impression cylinder 14 for the purpose of printing. The printed sheet W is transported and delivered by a delivery chain 26 via a delivery cylinder 25.
In such a rotary screen printing press, when the screen printing forme (stencil printing plate) of the rotary screen cylinder 22 is to be replaced, it has been common practice for two operators to hold opposite end portions of the screen printing forme in places near entrances 28 to the machine. This is because a forme or plate replacing work space S for replacing the screen printing forme of the rotary screen cylinder 22 has its upper side closed with a printing unit or a transport unit for the sheet W, and has its fore-and-aft direction restrained by other printing devices. Thus, the space S is only a narrow space defined by these printing devices. Moreover, the machine entrances 28 formed on both sides of a machine frame 27 are narrow. These situations make it difficult for one operator to do replacing work while holding the screen printing forme.
Thus, the two operators have to do the work in a well-coordinated manner with an unnatural posture, thus posing the problems of decreasing the operators' work efficiency and imposing a burden on the operators. | {
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1. Field of the Invention
The invention relates to sonar particularly with respect to linear hydrophone arrays for use in narrow underwater vehicles. The term "hydrophone array" is construed to include hydrophone/projector arrays.
2. Description of the Prior Art
Underwater vehicles generally utilize a forward-looking sonar for obstacle avoidance, mine detection, etc., a linear hydrophone array typically being mounted in the nose of the vehicle. Some of these vehicles tend to be small in diameter. A current evolutionary trend is toward Autonomous Underwater Vehicles (AUV) which can be launched from a submarine torpedo tube. Such an AUV is thus limited to a 21 inch diameter.
The imaging resolution achievable by the sonar is limited by the width of the linear array at a given sonar frequency. The wider the array, the better the resolution. Resolution can also be enhanced by utilizing higher sonar frequencies, but the higher the frequency, the lower the range capability of the sonar. Wide arrays can accommodate moderate resolution at a lower frequency, a lower frequency permitting greater range capability. Small vehicles, however, such as AUVs, are too small to accommodate wide arrays while stowed in their launch tubes or carrying fixtures.
For most underwater vehicles, design constraints limit the diameter of the vehicle body and, thus, the size of sonar hydrophone arrays contained within the body. For vehicles launched from a torpedo tube, the constraint is exacerbated. Because of these constraints, such vehicles have limited width hydrophone arrays resulting in poor resolution sonar data. Alternatively, the sonar design is limited to the use of relatively high frequencies which reduces sonar range capability.
The evolution in AUVs is toward reducing vehicle size to accommodate various methods for deployment; e.g., the 21 inch torpedo tube launchable vehicle class. However, reduction in overall vehicle size increases the need for greater vehicle autonomy resulting in a requirement for improved on-board sensors. As discussed above, however, improved resolution sonar sensors for a given sonar frequency tends to require a larger vehicle. The larger vehicle size requirement impedes the evolutionary trend toward smaller vehicles. | {
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1. Field of Invention
The present invention relates broadly to intravenous needle assemblies (catheter placement assemblies) and more particularly to needle assemblies comprising a hypodermic needle with a pointed end and a hub secured along the blunt end thereof, the hub carrying a transparent blood detection or flashback chamber so that the proper introduction of the needle into the vein can be ascertained by a showing of blood from said needle, within the blood detection chamber, while simultaneously permitting entering blood and displacement of air, but not blood from the interior of the detection chamber.
2. Prior Art
Heretofore, intravenous needle assemblies have employed metal needles and hubs, sometimes permitting no visual observation of blood following venipuncture until blood flows from the trailing end thereof. In other instances, transparent flashback chambers have been provided integral with a hub to permit early detection of the blood after it passes beyond the needle of the intravenous needle assembly. Still other such assemblies have employed plugs with an air removal feature. Some of these are not effective to reliably evacuate air; some require a separate operation to provide a uniform slit in a radial diaphragm. See U.S. Pat. No. 3,859,998. Such slits are expensive to produce and the end product is not of consistent reliability. Consequently, it has been a long standing problem to dependably produce air breather caps which are economical and effective to exhaust air while obviating blood loss following venipuncture. Additionally, the methods of producing breather caps or plugs are expensive and have sometimes created safety problems, e.g. the danger of loose particles. Further, prior art air bleed plugs contain a single narrow opening which may in any particular use be so oriented or clogged as to not permit full evacuation of air from the interior of the intravenous needle assembly. | {
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There are many drawing can covers with opening systems known from the state of the art. Generally, the beverage cans used nowadays have a stay-on tab with a rivet-fastened, ring-shaped metallic cover plate that is pressed towards the interior of the can, following the slitting line marked on the oval area of the cover. This opening system for drinking has the disadvantage that it cannot be closed once again after it has been opened.
A possibility of attaching a re-closable cover would be to join it to the top edge of the can. Such an embodiment has been described in DE 69809567T2, for example. However, the top edge of the can is attached during the filling process, leading to the following problems: The product spills out while the cover is being attached, the spilled-out liquid must be removed, a second cover must be immediately attached so filling speed is not affected and costs increase. In addition, attachment to the top edge of the can is difficult because the tolerance values are not sufficiently low and there can be up to 0.3 mm difference between two covers. An attachment to the top edge of the can would also lead to changed packaging modifications and transportation capability owing to the different piling height. This would lead to higher planning modification expenses for fewer products per volume. | {
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Conventional oscillators and voltage controlled oscillators (VCOs) used in integrated circuit (IC) designs are susceptible to phase or frequency error and are limited in frequency range due to instability across a wide bandwidth. Commonly used ring oscillators are notoriously susceptible to phase or frequency error, altering the resonant frequency proportional to any phase error induced in the loop. Phase error can come from a number of sources, but a dominant source is noise on voltage supplies causing jitter and hence phase error on circuit elements in the loop.
Conventional approaches to deal with phase noise have been orientated toward controlling noise sources rather than designing oscillators to be more immune to such noise. One exception are oscillators that use higher-order filters to lock in frequency independent of phase error. But such conventional oscillators are expensive to implement, requiring more accurate discrete components, which is not amenable to IC design. Also, tuning to a tight band may not be useful in applications requiring wide frequency ranges, such as VCOs or oscillators requiring tuning across frequency. | {
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The present disclosure relates to a recording medium cartridge with an improved reliability on an unintentional deletion prevention mechanism. In recent years, a disk cartridge that rotatably accommodates a disk-like recording medium such as an optical disc, a magneto optical disc, and a magnetic disk is widely used. In general, a disk cartridge is capable of recording and/or reproducing information signals including music signals, video signals, and programs. As such a disk-like recording medium capable of recording information signals, there are known, for example, a writable write-once disc and a rewritable disc with which rewrite is possible.
The disk cartridge of this type includes an unintentional deletion prevention mechanism for setting whether information can be recorded onto the disk-like recording medium. Patent Document 1 discloses, for example, a structure of an unintentional deletion prevention mechanism including an erroneous deletion preventing member that is slidable with respect to a cartridge main body and a detection hole formed on the cartridge main body.
The erroneous deletion preventing member selectively takes a recordable position at which information can be recorded onto a disk-like recording medium and an unrecordable position at which information cannot be recorded onto the disk-like recording medium. The detection hole is opened and closed in accordance with a movement of the erroneous deletion preventing member between the recordable position and the unrecordable position. Opened and closed states of the detection hole are detected by a drive apparatus (recording/reproducing apparatus) into which the disk cartridge is loaded. As a result, it becomes possible to prevent information from being recorded unintentionally onto the disk-like recording medium or information recorded onto the disk-like recording medium from being deleted unintentionally at a time the erroneous deletion preventing member is at the unrecordable position.
The erroneous deletion preventing member moves along a guide wall formed inside the cartridge main body. The erroneous deletion preventing member includes an elastic engagement part that elastically comes into contact with a side surface of the guide wall. On the side surface of the guide wall, a recording permission engagement recess and a recording inhibition engagement recess that engage with the elastic engagement part at a time the erroneous deletion preventing member is at the recordable position and the unrecordable position, respectively, are formed. Between the recording permission engagement recess and the recording inhibition engagement recess is a flat linear surface.
Patent Document 1: Japanese Patent Application Laid-open No. 2007-95206 (paragraphs [0045] to [0051], FIGS. 13 to 16)
In the unintentional deletion prevention mechanism of the related art described above, the guide wall that guides the movement of the erroneous deletion preventing member has a flat linear surface between the recording permission engagement recess and the recording inhibition engagement recess. Therefore, there is an inconvenience that, when the elastic engagement part of the erroneous deletion preventing member is stopped between the recording permission engagement recess and the recording inhibition engagement recess, the erroneous deletion preventing member is detected as being at the recordable position or at the unrecordable position depending on an opening level of the detection hole, with the result that detection accuracy on whether recording is possible is significantly lowered.
In particular, there is a case where, due to an unintentional drop of the disk cartridge, the erroneous deletion preventing member is moved by the drop impact and stops between the recordable position and the unrecordable position. In this case, the inconvenience described above is apt to occur, and a reliability of the unintentional deletion prevention mechanism cannot be secured.
In view of the circumstances as described above, it is desired to provide a recording medium cartridge that is capable of securing a reliability of an unintentional deletion prevention mechanism. | {
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1. Field of the Invention
The present invention relates to a method and apparatus for radially expanding a container body, to such radially expanded container body and to a container comprising such radially expanded container body.
2. Description of the Related Art
Presently, containers provided with a necked body portion are used for making containers, such as vacuum, pressurized or aerosol containers. Such containers comprise a container body having a necked portion to which necked portion is connected a top closure or cap. Such closure is generally residing within the cylindrical confinement of the container body. The other end of the container body is provided with a bottom end. For such containers having a different surface area at the bottom end and at the cap end, it is possible to use materials of different thickness. For instance, the bottom end has a diameter of about 65 mm and the cap end has a diameter of about 52 mm. At such bottom end the wall thickness may be about 0.18 mm. At the cap end, the cap might have a thickness of about 0.26-0.28 mm or thicker at larger diameters.
For such pressurized container having a necked portion it is traditional to produce the container body for such container by starting from a cylindrical container body produced by forming into a cylindrical shape a rectangular or square sheet of metal of which the abutting or overlapping longitudinal edges are welded together by a longitudinal weld seam.
Subsequently, this cylindrical container body having a longitudinal weld seam is subjected to radial expansion using punch means which are driven through one end of the cylindrical container body and urging radially outwardly the container body into a wider diameter while the punch means progressively are driven through the container body. During the radial expansion by driving the punch means through the cylindrical container body, the body is resting on a reaction table for resisting the driving forces of the punch means exerted on the inner surface of the container body.
The radially expanded container body produced with the traditional method as described above, shows various defects. First, there is a wavy structure over the longitudinal weld seam and over other areas in the outer surface of the cylindrical container body. Second, the end of the container body through which the punch means are driven for radially expanding the container body shows an irregular edge, predominately irregular when this end was provided with a flange intended for connection to the container bottom. Such irregular edge or flange edge at this container end is referred to as earring. This irregular edge may give rise to problems when connecting the bottom end to the container, preferably via the flange of the container body. The irregularities may amount from 0.1 to about 0.5 mm. Third, over the height of the cylindrical container body subjected to radial expansion the wall thickness is not substantially constant and tends to increase onward from the container body end where the radial expansion started.
The irregularities at the container body edge may be removed by cutting resulting in the formation of a substantially regular container body edge. However, such cutting operations are cumbersome and cost raising. | {
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1. Technical Field
The present invention relates to an AC direct drive lamp including a leakage current protection circuit, including an input stage configured to receive external power, a rectification circuit configured to rectify the external power received from the input stage, a control module electrically connected to the output stage of the rectification circuit and configured to sense and control the state of at least one of the rectification circuit, a switch module, and a light source, the switch module connected between the input stage and the control module in a feedback form and configured to switch on/off depending on a predetermined condition, and the light source electrically connected to the control module and configured to radiate light when power is applied.
2. Description of the Related Art
In a conventional LED lamp, as shown in FIG. 1A, an AC direct drive (or embedded type) lamp in which external power 120 is connected to one end 121 of an electrode of a lamp 130 has been implemented in an insulating drive type. In contrast, as shown in FIG. 1B, in a recent LED lamp, an AC direct drive (or embedded type) lamp in which external power 120 is connected to both ends 231 and 232 of the electrodes of a lamp 230 has been implemented in a non-insulating type.
Referring to FIG. 2, in the case of the AC direct drive lamp of a non-insulating type, a drive control module operates only when both ends 231 and 232 of a lamp 230 are normally connected before power 210 is applied. However, when one end 231 of the lamp 130 is connected to the power and the other end 232 of the lamp 130 comes into contact with a user 240 in the state in which the power 210 has been applied, there is a problem in that the user may be subject to a danger of a momentary electric shock because the leakage current flows into the ground GND.
Furthermore, a common mechanical type switch, such as a contact type push method, is used to prevent an electric shock attributable to the leakage current when a user replaces or repairs a lamp. However, when power is applied to the lamp, a driving voltage of about 1 kV is first applied for 0.2 second. If a product to which the mechanical type switch has been applied is used for a long time, power of a high voltage continues to be applied to a metal plate within the mechanical type switch. Accordingly, the mechanical type switch that needs to be an open state physically enters a short-circuit state temporarily. As a result, there is a problem in that a user is subject to a danger of a momentary electric shock.
Furthermore, the mechanical type switch has a problem in that a defect may occur because moisture may be penetrated between switches because waterproofing, that is, the most important issue of an LED lamp, cannot be applied to the mechanical type switch. Accordingly, research has been carried out on various methods for implementing an AC direct drive lamp, which block an instant overvoltage and prevent the leakage current. | {
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In wire harnesses for installation in a vehicle such as an automobile, there are cases where the applied electrical wire module that connects two devices includes a relatively rigid single-core wire and a relatively flexible stranded wire. In such a case, the electrical wire module relatively maintains its shape in the single-core wire portion, but bends relatively flexibly in the stranded wire portion.
For example, Patent Document 1 (JP S64-143862U) shows an example of an electrical wire module in which an end portion of a single-core wire is given a flat plate shape, and an end portion of a stranded wire is welded to the flat plate-shaped portion. | {
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Conventionally, a structure equipped with a side sill having a side sill upper member and a side sill lower member that are divided in the vehicle up-and-down direction has been known, for example, as disclosed in patent citation 1 (Japanese Utility Model Application Laid-Open (JP-U) No. H06-27452). | {
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Communication systems that are subject to space and weight limitations, such as mobile, manually deployable configurations, often employ (monofilar or bifilar) helical antennas, such as diagrammatically illustrated at 10 in FIG. 1. In order to optimize performance (produce as much gain as possible for a given deployed volume), it is desired that the DC power to radiated RF power efficiency of the radiating system be as high as possible. While this could be accomplished by the use of complex RF power amplifier circuits, the cost of such components is prohibitively expensive. As a consequence, it has been customary practice to use relatively low cost (reduced complexity) RF power amplifiers in the antenna signal feed path. Because such low cost RF amplifier components are also generally low efficiency (e.g., on the order of only fifteen percent) devices, multiple amplifiers are normally operated in parallel, and then summed to provide a combination of their individual amplifying powers.
For this purpose, as diagrammatically shown in FIG. 1, an RF input signal of interest is coupled to a signal splitter 11, which outputs a pair of RF signals to respective (low efficiency) RF amplifiers 12 and 13. The amplified RF signals produced by the RF amplifiers are then recombined or summed in a combiner 14, the output of which is coupled to a single feed port 15 of the helical antenna 10. Unfortunately, because the effect of the combiner 14 is substantial insertion loss, (including that of a signal hybrid, printed circuit board propagation, cabling, etc.) the effective irradiated power of resultant signal applied to the feed port 15 of the helical antenna is substantially below (on the order of one-half to one dB) that produced by the combined effect of the respective RF amplifiers 12 and 13, which degrades the overall power DC power to irradiated power conversion efficiency of the antenna and its RF amplifier feed network. | {
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In the prior art it is quite common to treat a polymeric material after its formation in order to improve its useful characteristics. Some of the better known treatments include exposure of the film to various forms of radiation, heat treatments including quenching, stretching, buffing, immersion in various chemical liquids, exposure to gaseous mediums, coating and lamination, etc. However, once a film has been coated and made the interior layer of a laminate it has heretofore been difficult, if not impossible, to further treat the interior layer. Accordingly, one object of the present invention is to provide a process for treating the interior layer of a laminate.
One reason why a film may be coated or laminated before treatment is completed is that it is often more economical to coextrude several layers of a tubular material in a single die or in a series of coextrusion dies and then stretch the coextruded tubing into film thicknesses. This way the film need only be handled once and all layers will be uniformly stretched and, in some instances, uniformly oriented. However, further treatment of an interior layer is not readily accomplished and it is another object of the present invention to provide a method of treating interior layers of a coextruded or extrusion laminated film.
In the prior art it has been found that the properties of nylon or polyamide film will improve beneficially with treatment by or exposure to water. For example, in U.S. Pat. No. 3,397,263, a process is disclosed for steam treating chill-cast nylon film to remove structural irregularities such as uneven film thicknesses. Likewise, in U.S. Pat. No. 3,651,200 a method is disclosed for orienting nylon film while it simultaneously adsorbs water. Therefore, it is still another object of the present invention to provide a method whereby a laminate having an interior layer of nylon may be beneficially treated with water.
The foregoing and many other objects will become obvious to those skilled in the art from the following summary and description of the invention. | {
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1. Field of the Invention
This invention relates to a semiconductor packaging structure in which lead frame conductors used to plug a semiconductor structure into a socket or pc board extend over and are adhesively joined to the surface of the chip via an insulated conductive ground plane structure positioned between the lead frame and the chip surface and electrically connected to a respective lead frame conductor. The remainder of the lead frame conductors may be electrically connected to respective terminals on the semiconductor chip surface.
2. Description of the Prior Art
U.S. Pat. No. 4,862,245 assigned to the same assignee as the present invention, describes a technique for positioning and affixing leads to a semiconductor chip prior to encapsulation of the chip in a protective coating by extending the lead frame over the surface of the chip.
A common problem with the prior art semiconductor package occurs when the lead frame becomes highly packed and when the underlying semiconductor device is a so-called high performance device in which a signal frequency is in the sub-nanosecond range, in such devices the noise level can rise above the signal levels and signals can become lost and the heat generated by the device can be significantly increased. This noise to signal ratio and increase in generated heat effectively limits the use of these devices when they are packaged as taught in the referenced patent.
It is an object of this invention to provide a packaged semiconductor chip with improved electrical and thermal performance.
Still another object of the invention is to provide a packaged semiconductor chip in which noise levels are maintained below the signal levels of the chip when it is operating at a sub-nanosecond signal transfer rate.
It is a further object of the invention to provide a packaged semiconductor chip which has reduced cross-talk.
It is still a further object of the invention to provide a packaged semiconductor chip which as improved heat transfer characteristics.
It is still another object of the invention to provide a plastic encapsulated semiconductor package in which the connecting lead frame members are deposited over the surface of the device together with a covering ground plane so as to provide enhanced electrical and thermal coupling of the members and the device and so reduce the signal to noise ratio by a factor of greater than three over that available in other similar plastic encapsulated packages while simultaneously improving the transfer of heat out of the package.
These and other objects of the present invention are provided by attaching a lead frame, having a plurality of conductors, to a major active surface of a semiconductor chip via a ground plane. In the preferred embodiment, a multilayered structure containing an insulated integral, uniform ground plane is positioned between the lead frame and the chip and is adhesively and insulatively joined to both of them. As will be described later different adhesives may be used to attached the interposer to the chip and to the lead frame Wires connect terminals on the major active surface of the semiconductor chip to the ground plane and to selective lead frame conductors. The lead frame, the ground plane structure, the semiconductor chip, and the wires which connect the semiconductor chip terminals to the ground plane and to selected lead frame conductors are encapsulated with a suitable insulating material to form a semiconductor module or package.
A bus bar can be provided that extends along the entire length of the semiconductor chip to serve both as a ground bus and as a means for further dissipating heat generated by the chip. This bus bar is connected to the integral ground plane structure as well as to selected terminals on the semiconductor chip.
These and other objects, features and advantages of the invention will becomes more apparent from the following particular description of the preferred embodiment of the invention as illustrated in the accompanying drawings. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a gauge for measuring the force exerted on a lever, and more particularly to a gauge for measuring the force required to pull a landing gear control lever to an extended position and to pivot the lever to either of its two control positions.
The landing gear on certain commercial airplanes is controlled from the cockpit by a landing gear control lever. This lever is pivotally mounted in the control panel of the cockpit for pivotal movement between a center "off" position, a raised position in which the hydraulic actuators are pressurized to raise or retract the landing gear, and a lowered position in which the hydraulic actuators are pressurized to lower or extend the landing gear. To prevent accidental movement of the landing gear control lever, it is designed to require that the lever be pulled out to an extended position before it can be pivotally moved to either the "up" or "down" position.
To facilitate the easy gripping of the end of the control lever so that it may be pulled to its extended position and then pivoted up or down to either control position, it is provided with a grip roller which is small enough that it does not encumber or clutter the front of the control panel but provides a secure and comfortable grip of the end of the control lever.
One of the quality control procedures for the manufacturing of airplanes is to insure that the force necessary to move the landing gear control lever is within design specifications. This is normally in the range of 7-10 pounds which insures that the lever can be easily and quickly moved when desired but that the force necessary to move the lever is sufficient to prevent its accidental or inadvertent movement by being bumped or the like.
The conventional technique for measuring the force necessary to move the lever used a spring scale which was attached to the end of the lever. The operator pulled on the end of the spring scale while watching the scale indicator to measure the force necessary to move the lever. This technique was inaccurate because the scale would show only momentarily the peak force exerted and required a skilled and experienced operator to obtain data with acceptable reliability. Even more importantly, the control panel of the cockpit in which the lever is installed has adjacent surfaces closely overhanging and underlying the space into which the control lever extends which make it very awkward to position the spring scale in line with the direction of movement of the lever so that the measured force would actually measure the force necessary to be exerted on the lever in the direction of motion.
Measurement precision of the force necessary to move the lever is advantageous not only because of the desire to maintain manufacturing processes within specification, but also because of the information that it reveals about the use of the hydraulic controllers and actuators in the system. The controllers for the actuators are designed to be essentially zero force movement controllers, meaning that the force necessary to move the actuator controller should be near zero. It is most convenient to measure the force necessary to move an actuator controller as installed in a operating system by measuring the force on the control lever, and therefore the instrument for measuring that force must be very precise to reveal the desired information about the controllers in the installed system.
Thus, there has long been a need in the industry for a gauge that will measure the force necessary to move a lever about its pivot point in such a way that the force exerted on the lever can be applied conveniently and quickly in the correct direction despite the confined position in which the lever is mounted. The instrument must be highly accurate and be capable of storing the desired information for reading and recording after the measurement is taken. The instrument should be capable of recording both tension and compression forces since the position of the lever may in some instances require that the force exerted on the lever be a pull and in other instances a push. The instrument should be easily mounted and dismounted from the landing gear control lever and, when mounted, be securely fixed to the lever. Finally, it should be small and light to facilitate its use in a cramped confines of the cockpit, should be inexpensive to manufacture, and be rugged for long use in the factory. | {
"pile_set_name": "USPTO Backgrounds"
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Spread spectrum techniques can be used to provide a degree of covertness and anti-jam capability to a communications system. In transmission, a spreading code is used to expand the bandwidth of transmitted signals. The transmitted signals can have a relatively large bandwidth as compared to the bandwidth of information encoded into the transmitted signals. For intended receivers, the spreading codes are known, and can be removed once synchronization has been obtained. The process of removing the spreading code in the receiver can also provide benefits in reducing the effects of interference and/or jamming (this benefit is sometimes referred to as processing gain). For adversaries who lack knowledge of the spreading code, detection of and synchronization to the transmitted signal can be difficult. Jamming a spread spectrum signal can also be difficult, since, without knowledge of the spreading code, the intended receiver gains an advantage over the would-be jammer approximately equal to the processing gain.
Spread spectrum processing adds some complexity and cost to a communications system. Detection and demodulation of a spread spectrum signal generally includes creating a local replica of the spreading code, synchronizing the timing of the local code replica to the transmitter, and removing the spreading code from the received signal. This additional processing can require additional signal processing hardware to be included in the communications system as compared to a conventional non-spread system.
Operating rates in a spread spectrum system are also typically much higher than conventional (non-spread) systems. For example, a conventional (non-spread) communications system operating at a 1 Mb/s data rate may use digital circuitry clocked at a 2 MHz rate. In contrast, a spread spectrum system operating at the same 1 Mb/s data rate may use a 100 MHz chip rate for the spreading code, and thus operate some of the digital circuitry at 50 or 100 times the clock rate of the conventional (non-spread) system. These higher clock rates can translate into higher hardware cost and higher power consumption.
Increasingly, communications systems are accommodating heterogeneous types of communications terminals. For example, some terminals in a system may be disadvantaged in terms of power availability or other characteristics. To provide communications in a spread spectrum system, it is generally necessary for all of the terminals in communications to operate using the same spreading codes and spreading (chipping) rates. Accordingly, to provide communications in a heterogeneous network has generally involved designing all of the terminals to operate using a particular combination of spreading code types, spreading rates, data rates, and other communications parameters. Such an approach can undesirability limit the overall capability of the communications system. For example, limiting all of the terminals in the network to provide only the minimum performance provided by the least capable terminal in the network may waste higher potential throughput available between some pairs of terminals. | {
"pile_set_name": "USPTO Backgrounds"
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