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The United States government has been helping businesses and individuals protect the environment through superior energy efficiency by backing programs, such as Energy Star. Energy Star is dynamic government/industry partnership that offers businesses and consumers energy-efficient solutions. For example, Energy Star published specifications for the maximum amount of power that a computer system should consume during particular states, such as a “hibernation state” and an “off state”.
In the “hibernation state”, the computer is operating in a power saving mode of operation in order to reduce power consumption. A computer system may be invoked to enter the hibernation state after a period of inactivity or upon a user invoking the computer system to enter the hibernation state. Upon entering hibernation, the computer system stores the contents of the system state information in a non-volatile storage unit, e.g., disk drive, flash Read Only Memory (ROM). During the hibernation state, the computer system consumes power to support the network subsystem. For example, the computer system may consume power to maintain activation of the network interface card. The network interface card may include logic configured to monitor a “magic packet” used to indicate to the computer system to “power up” to operate in the normal mode of operation. A magic packet may refer to a frame sent to the computer system in a network, e.g., local area network, that includes the destination address, e.g., address of the computer system, repeated a certain number of times, e.g., sixteen times, within the packet.
Similarly, in the “off state”, when the computer system is deactivated or turned off, the computer system may consume power to maintain activation of the network interface card. As discussed above, the network interface card may include logic configured to monitor a magic packet to indicate to the computer system to “power up” to operate in the normal mode of operation.
As stated above, Energy Star has published specifications for the amount of power that a computer system should consume during certain states, such as the hibernation state and the off state. Currently, Energy Star has specified that a computer system should consume no more than 2 watt of power during such states. Energy Star may later publish even more stringent specifications specifying that computer systems consume less than 2 watt of power during such states.
Therefore, there is a need in the art to reduce the power consumed by a computer system during the hibernation and the off state to comply with the Energy Star specifications. | {
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The invention relates to a method for operating an operating device of a motor vehicle. Such a method is known from DE 10 2009 034 068 A1.
DE 10 2009 034 068 A1 discloses a method in which gaze detection is used to check whether an operator's gazing direction is directed at a display unit during an input command for the operating device. If the gazing direction is not directed at the display unit during the input command, the input command is not executed. | {
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Post-mix dispenser systems are designed to mix a predetermined ratio of concentrate or syrup with water to produce a desired beverage upon demand. The amount of concentrate or syrup and water dispensed by the system varies, depending upon the type of beverage being produced. Typically, water to concentrate or syrup ratios of five to one or greater involve thick and viscous concentrates or syrups, such as for cola or orange juice. Dispenser systems have had difficulties in sufficiently mixing high ratios of water to concentrate or syrup. Often the resulting beverage has not been thoroughly mixed. Post-mix dispenser systems which must mix these thick and viscous concentrates and syrups have employed a variety of different techniques.
One technique involves adding a mechanical motor to drive one or more rotating blades in a mixing chamber through which the concentrate or syrup and water mixture passes. The rotating blades mix the concentrate or syrup and water to produce the beverage. Unfortunately, this solution requires substantial modifications to the dispenser system to make additional room for the rotating blades and motor.
Another technique of mixing a thick concentrate or syrup with water involves supplying the concentrate or syrup and water to the spout of the dispenser system at higher pressures than typically found in dispenser systems. At higher pressures, the concentrate or syrup and water are more thoroughly mixed within the spout. Unfortunately, to supply the concentrate or syrup and water at higher pressures and to withstand the higher pressures, requires substantial modifications to the dispenser system.
Accordingly, an object of this invention is to provide a nozzle which can thoroughly mix highly concentrated viscous liquids without substantial modifications to the dispenser system.
Another object of this invention is to provide a static mixing nozzle which does not require rotating blades and a motor to mix liquids.
Another object of this invention is to provide a mixing nozzle which operates at normal operating pressures for dispenser systems.
Another object of this invention is to provide a static mixing nozzle which is easy to clean.
Another object of this invention is to provide an inexpensive nozzle for mixing one or more liquids.
Another object of this invention is to provide an inexpensive nozzle insert which is easy to remove from the dispenser system. | {
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The invention relates to chairs in general, and more particularly to improvements in swivel chairs, for example, of the type disclosed in commonly owned U.S. Pat. No. 4,603,905 granted Aug. 5, 1986 to Felix Stucki for "Control mechanism for an adjustable chair or the like".
It is known to provide an office chair, particularly a swivel chair, with an adjustable seat and with a back rest which is articulately connected to a frame on top of a support of the leg of the chair. As a rule, the seat and the back support are provided with cushions which overlie suitably configurated shells and are or can be articulately connected to each other. The chair is provided with a discrete frame which is mounted on the support and is connected with the seat and back rest. The purpose of the frame is to transmit forces between the support on the one hand and the seat and back support on the other hand, especially to transmit forces which develop when the chair is occupied by a person. A drawback of the frame is that it contributes to the cost and bulk of the chair as well as that is detracts from the appearance of the chair. Moreover, the provision of a frame contributes to complexity of the adjusting mechanism which is normally provided to bring about changes in the positions of the seat and/or back rest relative to the support and/or relative to each other.
A typical discrete frame on top of the support of the leg is disclosed, for example, in German Offenlegungsschrift No. 29 25 520. The frame is directly affixed to the underside of the seat and is pivotally connected to the frame members of the back rest. The frame and other parts of the chair which is disclosed in this publication take up a substantial amount of space beneath the seat as well as behind the back rest. This detracts from the appearance of the chair.
German Utility Model No. 77 21 954 discloses a modified swivel chair wherein the support at the upper end of the upright column of the leg carries a discrete frame having a first part which is articulately connected to the front portion of the seat and a second part which is articulately connected to the rear portion of the seat. The rear portion of the seat is rigidly or movably connected with a one-piece back rest. The parts beneath the two-piece seat occupy a substantial amount of space and detract from the appearance of the chair.
A further conventional swivel chair is disclosed in German Utility Model No. 84 17 429. The back rest of this chair is located in front of a large frame which carries an adjusting mechanism for the back rest, and such frame is further coupled to a frame at the underside of the seat. The two frames are mounted on a further frame on top of the upright column of the leg. This chair exhibits the drawbacks of the aforediscussed conventional chairs. | {
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This invention relates generally to scalp massage devices. More particularly, the present invention is concerned with a readily portable scalp massage system in which vacuum suction and vibration are generated and distributed through apparatus enclosed by the helmet associated with the system. The system is believed classified in U.S. Class 128, Subclass 36.
As explained in my prior U.S. Pat. No. 4,469,092, a number of inventors have previously recognized the desirability of stimulating the human scalp, and a variety of electromechanical stimulating devices have been disclosed. Many known prior art devices typically include some form of movable or vibrating structure which massages the human scalp to promote health. For example, U.S. Pat. No. 3,753,853 issued Oct. 9, 1973, discloses a head vibrator including a plurality of massaging fingers projecting inwardly from a housing to contact the human skull. A vibrating system is employed to gently massage the skull by manipulating mechanical fingers.
U.S. Pat. Nos. 2,427,610 and 849,844 both depict vibrating devices which, when suitably placed relative to the skull of the wearer, stimulate the scalp by direct physical contact by a variety of moving fingers or "applicators". Other relatively similar devices are shown in U.S. Pat. Nos. 2,914,065 and 2,232,254. U.S. Pat. No. 2,706,980 discloses a scalp massage implement in which fingers are operated independently in separate groups. U.S. Pat. No. 1,861,924 discloses a vacuum operated head in which vibration is produced by air forced through a turbine system. The turbine includes eccentric weights for producing vibration. The latter device employs vibration in conjunction with suction to dislodge dirt particles for more effective vacuuming.
U.S. Pat. No. 4,469,092, issued to me on Sept. 4, 1984 discloses a scalp stimulating system which combines the advantage of rapid vibration distributed over a wide area of the scalp with concurrent suction. However, I have found it desirable to provide a scalp stimulating device in which the vacuum and vibration system are operationally associated within the helmet structure so as to more completely distribute massaging effects, while facilitating the comfort and convenience of the user. | {
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Knee osteoarthritis (OA) is symptomatic in 12.1% of Americans over 60 years of age. The patellofemoral joint is involved in 50% of all radiographic knee osteoarthritis cases in either an isolated form or combined with tibiofemoral OA. Despite the prevalence of patellofemoral OA, the patellofemoral joint has received relatively little attention in the OA literature and there are few treatment options for individuals with patellofemoral OA.
The patella rests in a groove at the distal end of the femur called the trochlear groove. When the knee is extended and flexed, the patella tracks superiorly and inferiorly, respectively, inside the groove. Both the posterior aspect of the patella and the trochlear groove are covered with articular cartilage that allows the bones to glide smoothly along each other as the leg is flexed and extended.
Patellofemoral arthritis occurs when the articular cartilage lining the trochlear groove and on the posterior aspect of the patella deteriorates and becomes inflamed. The joint space in the knee is narrowed due to the patellofemoral arthritis. Additionally, bone spurs may develop due to the arthritis in the knee.
As the articular cartilage deteriorates it becomes frayed, and when the wear is severe, the underlying bone may become exposed. Moving the bones along this rough surface generates friction and can be painful. Overload osteoarthritis, a condition that resembles osteoarthritis in any other joint, i.e., a gradually progressive thinning of the cartilage related to “normal wear and tear” that in this case is restricted to, or starts in, the patellofemoral compartment of the knee, may also occur.
In additional to patellofemoral arthritis, patellofemoral pain may also be the result of patellofemoral pain syndrome, patellar tendonitis, chondromalacia, and patella maltracking.
There are numerous devices that have been developed and marketed to help alleviate patellofemoral pain. The currently available devices generally either attempt to adjust the patella position and movement by pushing it inward (posteriorly) and/or medially or laterally. Some devices attempt to reduce the load on the patella by distributing the forces either above and/or below the knee joint and away from the patella region. However, a study disclosed in McWalter, et al., “The Effect of Patellar Brace on Three-Dimensional Patellar Kinematics in Patients with Lateral Patellofemoral Osteoarthritis,” Osteoarthritis Cartilage 19(7):801-808 (2011) concluded that while bracing changed patellar kinematics, the changes in kinematics did not provide a clinically meaningful reduction in pain in the study. Therefore, a need still exists for a device that can effectively manage patellofemoral joint pain and inflammation.
The present invention is directed to overcoming these and other deficiencies in the art. | {
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A gas and liquid mixture generation apparatus, such as an air bubble generation apparatus for generating fine air bubbles into a volume of liquid, has been conventionally expected to have a wide range of applications in different fields. Specifically, in one example, such an apparatus may be utilized to dissolve a volume of atmospheric air or other gases (such as oxygen, carbon dioxide, and nitrogen) in a volume of water (such as tap water, sea water, river water, lake water and purging water) or other liquid in an efficient manner for contribution to modifying liquid properties, purifying and enhancing water quality, and restoring aqueous environment. In addition to the above, there are some other possible applications in aquatic farming and breeding industry and general household use (such as in a bath room, kitchen and lavatory).
There have been suggested many different types of such air bubble generation apparatuses for generating fine air bubbles. Specifically, one such exemplary apparatus is a spinning type fine air bubble generation apparatus comprising: a container body having a space in a cylindrical or megaphone-like configuration having a bottom; a pressurized liquid introduction port opening at a part of a circumferential inner wall surface of the container body in a tangential direction relative to the inner wall; a gas introduction aperture opening at a bottom of the container body; and a spinning gas and liquid mixture delivery port opening at a tip of the container body (see Patent document 1).
In the above air bubble generation apparatus of the prior art, an operation thereof has been described as follows. Specifically, a volume of pressurized liquid is fed under a pressure through the pressurized liquid introduction port to cause a spinning flow inside the container body, which in turn produces a zone of a negative pressure around and along an axis of the cylindrical tube. Due to the presence of the negative pressure, a volume of gas is suctioned through the gas introduction port and as the gas flows past around and along the axis of the tube defining a lowest pressure zone, a narrow string-like spinning gas cavity is developed. The spinning gas cavity is torn apart by the pressurized liquid from the pressurized liquid introduction port, and in this event the fine air bubbles can be generated.
Further, a mist generation apparatus can be constructed by employing a similar structure to that of the air bubble generation apparatus described above. The mist generation apparatus may be applied diversely as described below. For example, the mist generation apparatus may be applied to desalination of the sea water and salt refining associated therewith. This is intended to separate the water content and the portion of salt and the like from each other by atomizing a volume of sea water into fine particles of mist and then heating the mist to allow the water content to evaporate instantly. The evaporated water content may be cooled to form a volume of plain water, while the salt can be produced at the same time.
The above apparatus may be similarly applicable in refining for fine powder of materials. This is intended to produce fine powder of materials by atomizing a volume of solvent mixed with an amount of metal, painting material, cosmetic material and the like to form fine particles of mist and drying thus finely atomized liquid drops instantly by bringing a hot air into contact with them.
In addition, the above apparatus may be similarly applicable to an environmental control for a greenhouse cultivation facility and the like. In this application, specifically the apparatus may serve for such operation as humidification, temperature control, water supply and so on for cultivated plants and the like.
Yet further, the above apparatus may be similarly applicable to a plant environmental sanitation control (such as, bacteria elimination, deodorization, odor elimination, bactericidal cleaning, temperature and moisture control, and measures against dust, in a space). This means that using the above apparatus in combination with a drug solution allows to accomplish the bacteria elimination, cleaning, odor elimination and temperature and moisture control in the space inside the target environment or facility (such as, inside a plant for food or for drugs and medicines, a medical facility, a distribution facility, a stable, a vehicle and the like).
The above mist generation apparatus may be also applicable to an environmental control for controlling a spatial environment (such as, a fairground and a working site). In this application, the apparatus is operable effectively for cooling down a high-temperature condition developed from a heat-island phenomenon, as measures to prevent heat stroke, and for managing a high temperature condition due to heat from displays. Specifically, in summer time, the control (cooling down, suppressing dusts) of the environment of the site or space containing a crowd of people gathering together may be provided by releasing finely atomized particles of mist into the space.
Further, the above apparatus may be used in disaster prevention and fire control facilities. In this application, the apparatus may be used as a dust suppressing device for preventing an accidental explosion of dust or as a device substituting for a sprinkler head (that can provide a comparative effect only with a small amount of water).
Yet further, the above apparatus may be applicable to health-care equipment, for example, to control a temperature or moisture and to provide a mist shower using a hot water.
In addition to those, the above apparatus is applicable to a recycling business from the viewpoint of the environmental issues. Specifically, the finely atomized particles of mist may be sprayed against a toxic emission gas discharging to the atmosphere from chemical plants, industrial waste incineration facilities, sludge incineration facility and the like so that the toxic gas can be adsorbed to a water content of the mist for collection and further handling. [Patent document] International Patent Laid-open Publication No. WO00/69550, Booklet (FIG. 1) | {
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In producing petroleum and other useful fluids from production wells, it is generally known to provide a submergible pumping system for raising the fluids collected in a well. Production fluids enter a wellbore via perforations formed in a well casing adjacent a production formation. Fluids contained in the formation collect in the wellbore and may be raised by the submergible pumping system to a collection point above the earth's surface.
In an exemplary submergible pumping system, the system includes several components, such as a submergible electric motor that supplies energy to a submergible pump. The system may further include additional components, such as a protector, for isolating the motor oil from well fluids. A connector also is used to connect the submergible pumping system to a deployment system. These and other components may be combined in the overall submergible pumping system.
Conventional submergible pumping systems are deployed within a wellbore by tubing, cable, or coiled tubing. Power is supplied to the submergible electric motor via a power cable that runs along the deployment system. For example, with coiled tubing, the power cable is either banded to the outside of the coiled tubing or disposed internally within the hollow interior formed by the coiled tubing.
Power cables typically contain conductors for powering the submergible motor. The motor conductors, typically three conductors, extend along the deployment system to the submergible pumping system where they are hardwired to the motor. The actual conductors may be routed through the connector or alongside the connector.
Regardless of the specific method used for connecting the power cable, the conductors are connected to the motor and the deployment system is attached to the connector prior to deployment of the submergible pumping system. When the conductors of the power cable are connected to the submergible pumping system, the connection point must be prepared carefully to ensure isolation from the relatively hostile environment within a wellbore. For example, if the conductors are routed into the motor, the point of entrance must be rigorously sealed from the fluids and environment in which the submergible motor is disposed. Conventional connection methods for connecting the power cable to the motor are time-consuming and can be subject to failure if careful attention is not paid to sealing any connection points from the wellbore environment.
It would be advantageous to utilize a modular system suited for easy connection of the power cable to the submergible motor or any other components requiring a control input or a communication line. | {
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1. Field of the Invention
The present invention relates to an exposure-data generating apparatus, and in particular to an apparatus that generates exposure data for driving a two-dimensional display device such as a DMD (Digital Micro-mirror Device).
2. Description of the Related Art
A multiple exposure apparatus that uses the two-dimensional display device such as the DMD is proposed.
In the multiple exposure apparatus that uses the two-dimensional display device such as the DMD, the exposure data that is used for driving the two-dimensional display device is generated on the basis of drawing data such as bitmap data and a cell coordinate corresponding to a cell number of a cell constituting an element of the two-dimensional display device, as shown in Japanese unexamined patent publication (KOKAI) No. 2003-50469.
However, when the exposure data is generated, the cell coordinate is read from the cell coordinate table that stores the cell coordinate at every cell unit. In this case, the number of accesses to the cell coordinate table for generating the exposure data equals the number of cells. Therefore, one of the causes hindering the speed-up of exposure data generation is that there are numerous accesses to the cell coordinate table. | {
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The desire to maintain a youthful appearance by preventing or reducing wrinkles in the skin is an important issue in human society. Many techniques have been designed to achieve the above issue. One of the techniques known from the published international patent application WO 2008/001284 A2 is to create a focal spot in a dermis layer of the skin to be treated. Said WO application discloses a skin treatment device with a laser source and focusing optics, wherein the power of the laser is selected such that Laser Induced Optical Breakdown (LIOB) affects the skin in order to stimulate re-growth of skin tissue and reduce wrinkles. This LIOB is based on strong non-linear absorption of the laser light by the skin tissue, which occurs above a certain threshold value of the power density of the laser light in the focal spot of the laser beam. This strong absorption causes a localized plasma that is able to damage or even remove tissue at the location of said plasma. This is caused by secondary, primarily mechanical, effects such as rapid expansion of the generated plasma. This effect is very local because, below the threshold, there is zero or very little linear and non-linear absorption while, above the threshold, a plasma is generated which even more strongly absorbs the laser light. In other words, effects such as LIOB only occur in the focal spot, while above and below the focal spot no or very much weaker effects occur. This means that, for example, the epidermis may easily be safeguarded against undesired effects or damage.
Laser skin ablation through a multiphoton ionization process, such as for example laser induced optical breakdown, requires high light intensities of the order of 1013 W/cm2. Due to a very high photon flux (typically >1031 cm−2 s−1), multiple (N) photons with an energy of hv at the wavelength of λ behave like a photon of energy Nhv and interact with an electron to free it from the valence band. This requires the total energy of the absorbed photons to be greater than the ionization potential (Nhv>Δ). The generation of this so-called seed electron or free electron by ionization requires multiple photons (N) having the same polarization confined in space (focal volume) and in time (˜nano to femto seconds) with a total energy exceeding the ionization potential (Nhv>Δ) of the material. Achieving a multiphoton ionization process deep inside the skin is a challenging task.
US2013/0199540 A1 discloses a device for plasma treatment of living tissue, with a plasma source for generating an atmospheric plasma jet, with a support device for a body part comprising the tissue to be treated, with a movement device for moving the plasma source relative to the surface of the tissue, and with a control device for controlling the movement device and for controlling the operation of the plasma source, wherein the control device has means for adjusting the plasma output as a function of the position relative to the tissue. In an embodiment, the device has optical means for measuring a distance between the front end of the outlet opening of the plasma jet and the object to be treated. Said optical means comprise a laser source generating a laser beam which is directed towards the object to be treated through a channel formed in the internal electrode of the plasma generator. The laser beam reflected by the object is directed in opposite direction through the channel and is reflected to a photosensor by means of an output coupling mirror. In another embodiment, before, during and after the plasma treatment a heat treatment, light treatment and/or laser treatment can be carried out. These additional treatments can support and extend the way in which the plasma treatment works. | {
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This invention generally relates to viewing devices and, in particular, to viewing devices which allow viewing at right angles without inverting the image. The invention is especially useful for viewing in a horizontal direction from a prone or supine position.
There are certain types of eye surgery which require the patient to maintain a face-down position with a minimum of eye movement for extended periods of time, up to several weeks. While in this position, the person obviously has very limited ability to perform many ordinary functions, such as reading, viewing television, or seeing little more than the feet of those giving assistance or visiting during this recovery period.
While the use of a mirror may seem an obvious solution to this problem, objects would appear upside down and backwards. Reading in this manner obviously would be next to impossible, and attempts at viewing other things would appear quite abnormal.
The device described here allows the patient to see horizontally while looking in a downward or upward direction, and to view the object in a completely normal and upright orientation.
A viewing device according to the invention provides an unobstructed viewing path which is essentially horizontal, while the gaze of the person remains in a vertical direction. More specifically, a first reflective surface directs the view toward a second reflecting surface, which directs the view in a horizontal direction. The image as seen by the person is non-inverted and clearly visible, as if viewing it directly without the device.
According to an aspect of the invention, a method of viewing in a generally horizontal direction from a prone or supine position includes providing at least two surfaces having reflective portions oriented at an acute angle to each other. One of the reflective surface portions is positioned in the user""s line of sight. The other of the reflective surface portions is positioned in an optical path extending to an area to be viewed. The user looks into one of the reflective surface portions and views objects along the optical path.
According to another aspect of the invention, a viewing device includes a housing and at least two surfaces having reflective portions supported at the housing. The at least two surface reflective portions are oriented at an acute angle to each other. An object viewed in one of the reflective surface portions is reflected from the other of the reflective surface portions. This provides non-inverted images of objects viewed at an approximate right angle from the direction of viewing.
According to yet another aspect of the invention, a viewing device includes a housing formed in a generally Z-shape defining two support surfaces at an acute angle to each other. A first reflective surface is positioned on one of the support surfaces and a second reflective surface is positioned on the other of the support surfaces.
These and other objects, advantages and features of this invention will become apparent upon review of the following specification in conjunction with the drawings. | {
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Structures, e.g., conventional collapsible dish structures with flexible mesh or flexible surfaces, that can be folded during transit and deployed upon reaching their destination have been widely used, particularly in situations in which cargo space is limited or otherwise at a premium. Advantageously, collapsible structures may be stowed compactly in a vehicle while not in use, and then deployed to a desired configuration to perform a given application. Although the space-saving characteristics of collapsible structures benefit many applications, space applications in particular stand to benefit to a high degree due to the limited amount of cargo space onboard a spacecraft and the high cost of space travel.
Recent spacecraft applications have mandated the use of shorter wavelengths in the electromagnetic spectrum, as well as an increased interest in the collection and focusing of light waves in space, collapsible dish structures have been required to meet stringent requirements for surface smoothness and contour control to minimize scattering and improve antenna gain. These requirements have resulted in an increased dependence on the type of antenna, which utilize solid panels. These solid panel type antennas are more suitable for short and optical wavelengths as compared with mesh collapsible antenna designs.
Several approaches currently are used to address the transportation of deployable rigid antenna systems on a spacecraft. One conventional method of packaging includes hinging segments only on the inside edges of the segments. The segments are then stowed, alternately forward and aft, and then opened out to the final positions. Another example of a conventional method includes stacking the segments horizontally, either individually or in pairs, where the segments or the pairs are not fully connected at the edges. During deployment, the segments are swung into their respective final positions. Yet another conventional method of packaging involves stacking the segments vertically, either individually or in pairs, where the segments or the pairs are not fully connected together at the edges. During deployment, the segments are moved into their final positions.
These conventional methods of packaging segmented rigid reflectors suffer from complexity in the implementation of the packaging and result in inefficient use of the stowed volume, and problematic gaps between the deployed segments or between pairs of segments. | {
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1. Field
The disclosure relates to a method, system, and article of manufacture for the adjustment of the number of task control blocks allocated for discard scans.
2. Background
A storage controller may be coupled to one or more of a plurality of hosts. The storage controller may manage a plurality of storage devices, such as disk drives, tape drives, etc., that are coupled to the storage controller. The plurality of hosts may access data stored in the storage devices via the storage controller.
The storage controller may maintain a cache, where a cache is a type of storage that is capable of providing faster access to data in comparison to storage devices such as disk drives or tape drives. The storage space provided by the cache is smaller in size than the storage space provided by the disk drives or tape drives, where the storage provided by the disk drives or tape drives, and other devices, may be referred to as secondary storage. As a result, tracks may need to be staged (i.e., moved to the cache from secondary storage) or destaged (i.e., moved from the secondary storage to the cache) to prevent the cache from becoming full and to provide faster access to data. In many situations, to release space in the cache, tracks may be discarded from the cache via discard scans.
A “Task Control Block” (TCB) is a data structure in the operating system kernel containing the information needed to manage a particular process. Storage controllers may move information to and from storage devices, and to and from the cache by using TCBs to manage the movement of data. | {
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This invention pertains to minimally invasive surgery of the lung. In particular, it applies to application of brachytherapy techniques directed primarily to lung or pleural tissue surfaces exposed by or created as a result of tumor resection or the presence of primary cancer of the pleura. As with other tumor resection procedures, and even when pathology shows “clear” margins, there is potential for disease recurrence from diffuse proliferative disease in the resected surfaces. Balloon brachytherapy as an adjuvant follow-up to resection has been shown to reduce the likelihood of such recurrent disease.
Recent advances in surgical treatment of proliferative diseases of the lung include endoscopic procedures conducted through, and directed to lesions near the bronchi, and alternatively, video-assisted, minimally-invasive thoracic surgery directed to more peripheral disease and performed through incisions providing access to the thoracic cavity.
Today with early stage carcinoma of the lung, particularly in peripheral portions of the lung, treatment consists of resecting a wedge-shaped portion of lung through small incisions between adjacent ribs. If a wedge resection is inadequate to excise the entirety of the tumor, a lobectomy may be performed, removing a complete pulmonary lobe. Visualization is provided by camera or conventional fiber optic means mounted on a thoroscope and monitor display, although other state-of-the-art modalities can be used. Percutaneous or other methods or small incisions are used to introduce the necessary instrumentation, and with newer, minimally invasive techniques, conventional rib spreading is not required. The absence of rib spreading greatly reduces pain and hastens patient recovery, but narrows instrument access to a few small, discrete points on the rib cage. In order to provide adjuvant brachytherapy, methods and apparatus are needed that are compatible with the methods described above, and preferably without requiring additional access beyond that already established during resection.
With the intrabronchial approach to treatment of obstructions or lesions, a flexible bronchoscope with a working channel is generally employed in the affected bronchus while the remaining bronchial tree provides intraoperative ventilation. The bronchoscope also comprises either camera or fiber optic means to provide monitor display. Other instrumentation, preferably including that for follow-up brachytherapy, must be flexible, and of appropriate diameter for operation from within the working channel in order to be compatible. Extra or intrabronchial procedures often involve removal of a diseased section of bronchus, after which the exposed ends are usually approximated, either by suture or staple methods. Adjuvant brachytherapy may also be indicated after extra or intrabronchial surgery.
Brachytherapy practice traditionally comprises positioning a radiation source within target tissue and delivering a therapeutic dose of radiation, often from within a balloon, without overdosing either target or adjacent tissue. One particularly useful class of radiation sources are miniature electronic x-ray tubes which may be switched on and off at will, or which can be modulated with respect to either penetration depth (by controlling acceleration voltage of the x-ray tube) or dose intensity (by controlling filament current). These tubes are usually mounted at the end of a power supply cable and can emit isotropically or can be directional, emitting through a predetermined solid angle. One reference describing the principles and construction of such tubes is Atoms, Radiation and Radiation Protection, Second Edition, John E. Turner, Ph.D., CHP, 1995, John Wiley & Sons, Section 2.10. By contrast, isotope sources cannot in principle be modulated, and in addition require both isolation of the patient during radiotherapy and special facilities and apparatus to assure safety of personnel.
A minimum therapeutic absorbed dose (the prescription dose) is selected by the therapist to be delivered to all of the target tissue. Because dose generally decreases exponentially with distance from the source, accurate dose delivery is complicated and automated treatment planning is generally employed to assure delivery of a dose to the target tissue which is at least equal to the prescription dose, but which is also within allowable limits, thus avoiding substantial necrosis of normal tissue. The prescription dose may of necessity vary depending on the proximity of the source to radiation sensitive structures within the anatomy. Examples would include the skin, heart or other organs, and bone. Treatment planning is usually automated based on known radiation source parameters, prescription parameters, and geometry as determined by conventional imaging of the apparatus within tissue. Planning usually precedes the treatment delivery.
A useful device for controlling radiation intensity is an applicator, preferably a balloon applicator. Balloon applicators generally determine the interior shape of the target tissue (the resection cavity) and position the radiation source at a controlled distance from the tissue to be treated, thus defining treatment geometry and reducing the radiation intensity exponentially from spatial considerations. Several other means are available to moderate the absorbed dose delivered to the tissue. As noted above, the acceleration voltage applied to the x-ray tube can be used to limit the penetration depth of the radiation. The filament current can be reduced to lower emitted intensity, or in fact, to eliminate emissions altogether. Once output emission characteristics are determined by selection of x-ray tube input parameters, shielding can be used to reduce radiation intensity, or to control the direction of emissions, statically or dynamically as therapy progresses. Such shielding and attenuation methods for x-ray tubes are described in copending application Ser. Nos. 11/385,255, 11/471,277 and 11/471,013, each of which is incorporated herein in their entirety by reference.
Balloon applicators are known, for example those described in U.S. Pat. No. 6,413,204. In general, such applicators comprise a balloon mounted on a shaft proximate the distal end of the shaft, and further comprise at least one source guide to position the source at a known distance or distances from the balloon (and tissue cavity) surface. Fluid circuits can be provided communicating from outside the patient to the interior of the balloon for inflation purposes, or to outside the shaft and/or balloon for example for suction purposes or administration of anesthetic or therapeutic agents. | {
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1. Field of the Invention
The present invention generally relates to a static-type semiconductor memory device and a field effect transistor and methods of manufacturing the same, and, more particularly, to a thin film transistor (TFT), a method of manufacturing a TFT, a static-type semiconductor memory device provided with a memory cell having a complementary field effect transistor and a method of manufacturing the same. The present invention is particularly useful in conjunction with a CMOS-type SRAM (Static Random Access Memory) to which a TFT is applied.
2. Description of the Background Art
What is called a SRAM is already well known as a static-type semiconductor memory device. Since the present invention has the most preferable effects when it is applied to a SRAM, a SRAM will be described in the following.
FIG. 16A is an equivalent circuit diagram illustrating one memory cell in a conventional CMOS-type SRAM. FIG. 16B is a plan view schematically illustrating an arrangement in the memory cell in the SRAM illustrated in FIG. 16A. FIG. 16C is a cross sectional view schematically illustrating a cross sectional structure of the memory cell in the SRAM illustrated in FIG. 16A.
Referring to FIGS. 16A-16C, a flip-flop type memory cell is implemented, including two driver transistors (n-channel MOS transistors) Q3, Q4 having the gate electrodes and drain electrodes cross-coupled and two load transistors (p-channel MOS transistors) Q5, Q6 connected, respectively, to the drain electrodes of driver transistors. Two access transistors (n-channel MOS transistors) Q1, Q2 are connected, respectively, to the drain electrodes of the two driver transistors Q3, Q4. The gate electrodes of access transistors Q1, Q2 are connected to a word line WL. When the word line WL is selected, data held in driver transistors Q3, Q4 are transferred through access transistors Q1, Q2 to bit lines BLa, BLb. One memory cell node N1 is connected to the drain electrode of driver transistor Q3, to the gate electrode of driver transistor Q4, to the drain electrode of load transistor Q5, and to the gate electrode of load transistor Q6. The other memory cell node N2 is connected to the gate electrode of driver transistor Q3, to the drain electrode of driver transistor Q4, to the gate electrode of load transistor Q5, and to the drain electrode of load transistor Q6. Source electrodes of driver transistors Q3, Q4 are connected to a ground potential GND. Source electrodes of load transistors Q5 Q6 are connected to a supply potential Vcc.
The drain electrodes and the gate electrodes of driver transistors Q3, Q4 are mutually cross-connected to form a flipflop circuit having two stable states. This enables storing of bit data. Specifically, data of one bit can be stored by holding a state in which the potential of one memory cell node N1 is at "High" level, and the potential of the other memory cell node N2 is at "Low" level, or a state which is reverse to that state. When a desired memory cell is selected, i.e. when the word line WL is at "High" level, access transistors Q1, Q2 are brought to ON state. This causes memory cell nodes N1, N2 to be conduct to bit lines Bla, Blb. At this time, voltages corresponding to the states of respective driver transistors Q3, Q4 come to appear on bit lines BLa, BLb through access transistors Q1, Q2. Thus, data held in the memory cell is read. When data is written into the memory cell, voltages corresponding to desired states to be written are applied to respective bit lines BLa, BLb with access transistors Q1, Q2 in ON state. In order to maintain the state of storing data latched by the flip-flop circuit implemented with driver transistors Q3, Q4, current is supplied from supply potential Vcc through load transistors Q5, Q6.
As described above, a memory cell in a CMOS-type SRAM is implemented with six transistors Q1-Q6. Therefore, as illustrated in FIG. 16B, a region where four n-channel MOS transistors are formed and a region where two p-channel MOS transistors are formed are necessary for constituting a memory cell. In addition, as illustrated in FIG. 16C, a p-type well region (p-Well) and an n-type well region (n-Well) are necessary for forming the n-channel MOS transistors and the p-channel MOS transistors in a semiconductor substrate. Therefore, a large flat area is necessary for forming a memory cell in a CMOS-type SRAM as long as a bulk-type MOS transistor (a MOS transistor formed on the surface of a semiconductor substrate) is used. Accordingly, a memory cell in a CMOS-type SRAM implemented with a bulk MOS transistor is disadvantageous for achieving high density.
High resistance load type memory cell has one structure of a memory cell in SRAM for solving the above problem and enabling high densification. FIG. 17A is an equivalent circuit diagram illustrating a structure of a memory cell in a SRAM of a high resistance load type. FIG. 17B is a plan view schematically illustrating an arrangement in the memory cell illustrated in FIG. 17 A. FIG. 17C is a cross sectional view schematically illustrating a cross sectional structure of the memory cell illustrated in FIG. 17A.
Referring to FIGS. 17A-17C, a flip-flop type memory cell is implemented, including two driver transistors (n-channel MOS transistors) Q3, Q4 having the gate electrodes and drain electrodes respectively cross-coupled and two high resistance loads HR1, HR2 connected, respectively, to the drain electrodes of the driver transistors. Two access transistors (n-channel MOS transistors) Q1, Q2 are connected to the drain electrodes of two driver transistors Q3, Q4, respectively. The gate electrodes of access transistors Q1, Q2 are connected to a word line WL. When the word line WL is selected, data held in driver transistors Q3, Q4 are transferred through access transistors Q1, Q2 to bit lines BLa, BLb. One memory cell node N1 is connected to the drain electrode of driver transistor Q3 and to the gate electrode of driver transistor Q4. The other memory cell node N2 is connected to the gate electrode of drive transistor Q3 and to the drain electrode of driver transistor Q4. Source electrodes of driver transistors Q3, Q4 are connected to a ground potential GND. The drain electrodes of driver transistors Q3, Q4 are connected through high resistance loads HR1, HR2 to a supply potential Vcc.
In the high resistance load-type memory cell implemented as described above, driver transistors Q3, Q4 have the drain electrodes and gate electrodes mutually cross-connected to form a flip-flop circuit having two stable states as in a CMOS-type memory cell. This enables storing of bit data. The data reading operation and data writing operation are the same as in the above-described memory cell of CMOS type. This memory cell differs from the memory cell of CMOS type in that current is supplied from supply potential Vcc through high resistance loads HR1, HR2 for maintaining the state of storing data latched by the flip-flop circuit implemented with driver transistors Q3, Q4.
As described above, a high resistance load type memory cell is implemented with four transistors Q1-Q4 and two high resistance loads HR1, HR2. As illustrated in FIG. 17B, in order to form a high resistance load type memory cell, first, a region where four n-channel MOS transistors are to be formed is secured. A high resistance load HR is formed on two n-channel MOS transistors constituting driver transistors Q3, Q4. As illustrated in FIG. 17C, only a p-type well region (p-Well) is necessary for implementing a high resistance load type memory cell. Therefore, the flat area necessary for a memory cell is smaller as compared to a memory cell of CMOS type which requires a p-type well and an n-type well in a memory cell. Accordingly, a high resistance load type memory cell is advantageous for high densification SRAM.
However, in the high resistance load type memory cell, current is supplied from supply potential Vcc through high resistance loads HR1, HR2 for maintaining state of storing data latched by the flip-flop circuit implemented with driver transistors Q3, Q4. It is desired that the current is small for suppressing power consumption during waiting. Therefore, it is necessary make the electrical resistance value of the high resistance loads as high as possible. However, there is a limit to the resistance of the resistance loads, and it is necessary that current flowing in the high resistance loads for holding data is larger than the leakage current in the case where the transistor is off. On the other hand, in the memory cell of CMOS type, current is supplied from supply potential Vcc through load transistors (p-channel MOS transistors) Q5, Q6 for maintaining the state of storing data latched by the flip-flop circuit. Therefore, it is possible to reduce current consumption during waiting to the level of the junction leakage current. As described above, although the high resistance load type memory cell is advantageous for high densification of a SRAM, the memory cell of CMOS type is advantageous for reducing current consumption to hold the state of storing data, i.e. for suppressing power consumption during waiting.
In consideration of the above respects, a structure of a CMOS-type memory cell capable of achieving high densification of a SRAM is proposed. FIG. 18A is a plan view schematically illustrating an arrangement in a memory cell implemented by reducing the occupied flat area in the memory cell of CMOS type illustrated in FIG. 16A. FIG. 18B is a cross sectional view corresponding to FIG. 18A.
Referring to FIGS. 16A and 18A-18B, p-channel thin film transistors (TFTs) are adapted, as load transistors Q5, Q6, instead of bulk-type p-channel MOS transistors. Therefore, as illustrated in FIG. 18A, a region for formation of four n-channel MOS transistors is required for implementing a memory cell. p-channel TFTs constituting load transistors Q5, Q6 are formed on n-channel MOS transistors constituting driver transistors Q3, Q4. As illustrated in FIG. 18B, four bulk-type n-channel MOS transistors are formed in a p-type well region (p-Well). If p-channel TFTs are adapted as load transistors like this, only a p-type well region is required for forming one memory cell. Therefore, it is possible to reduce the flat area occupied by a memory cell CMOS type and to provide a structure of a memory cell of CMOS type advantageous for high densification by adapting a p-channel TFT.
A memory cell in a SRAM of CMOS type in which a p-channel TFT including a polycrystalline silicon layer is adapted as a load transistor is disclosed in "A 25 .mu.m.sup.2 New Poly-Si PMOS Load (PPL) SRAM Cell Having Excellent Soft Error Immunity" IEDM, 1988, pp. 48-51. FIG. 19 is a partial plan view illustrating an arrangement in only the upper layer part in such a memory cell in a SRAM. FIG. 20 is a partial cross sectional view illustrating a cross sectional structure taken along line XX--XX in FIG. 19. FIGS. 21A-21C are partial cross sectional views illustrating a method of manufacturing the memory cell illustrated in FIG. 20, particularly, sequentially illustrating cross sectional structures in respective steps of a method of forming a p-channel TFT constituting a load transistor.
Referring to FIGS. 19 and 20, an n-type well region 502 and a p-type well region 503 are sequentially formed on a p-type silicon substrate 501. An n.sup.+ impurity region 209 of an n-channel MOS transistor constituting a driver transistor or an access transistor is formed in p-type well region 503. An isolating oxide film 200 is formed for isolating each n-channel MOS transistor. Gate electrodes 201, 202 of a first polycrystalline silicon layer are formed on p-type well region 503 with a gate insulating film 210 interposed therebetween. Gate electrodes 201, 202 constitute the gate of an access transistor or a driver transistor. A gate electrode 204 of a second polycrystalline silicon layer is formed on gate electrodes 201, 202 with an insulating film interposed therebetween. Gate electrode 204 constitutes the gates of p-channel TFTs as load transistors Q5, Q6. A source region 206a, a channel region 206, and a drain region 206b of a TFT of a third polycrystalline silicon layer are formed on gate electrode 204 with a gate insulating film 212 interposed therebetween. Source region 206a of the TFT constitutes power supply interconnection line Vcc. Drain region 206b of each TFT is connected through a contact hole 205 to gate electrode 204 of another TFT. An interlayer insulating film 214 is formed to cover each transistor. A refractory metal layer 207a is formed to be in contact with n.sup.+ impurity region 209 through a contact hole 208. An interlayer insulating 216 is formed on refractory metal layer 207a. An aluminum metal layer 207b is connected to refractory metal layer 207a. A bit line is constituted with aluminum metal layer 207b.
A method of manufacturing the memory cell in a SRAM formed as described above, particularly a method of manufacturing a p-channel TFT, will be described with reference to FIGS. 21A-21C.
Referring to FIG. 21A, an isolating oxide film 200, an n.sup.+ impurity region 209, a gate insulating film 210 and gate electrodes 201, 202 are formed in a p-type well region 503 to constitute a driver transistor or an access transistor. An interlayer insulating film 211 is formed to cover each transistor. A second layer of a polycrystalline silicon layer is formed on interlayer insulating film 211 by a low pressure CVD process, for example. Arsenic ions are implanted into the polycrystalline silicon layer, and then the polycrystalline silicon layer is patterned to form a gale electrode 204 of a p-channel TFT which constitutes a load transistor. Gate electrode 204 is formed to be connected to gate electrode 202 of a driver transistor in a part.
Then, as illustrated in FIG. 21B, an oxide film, for example, which constitutes a gate insulating film 212 is formed on the whole surface by a low pressure CVD process. Gate insulating film 212 is patterned as needed, and then a third layer of a polycrystalline silicon layer is formed by a low pressure CVD process, for example. The polycrystalline silicon layer is patterned to form a polycrystalline silicon layer 206 to be source, channel and drain regions of a TFT. A region of polycrystalline silicon layer 206 corresponding to the drain region of the TFT is connected to gate electrode 204 of another TFT.
As illustrated in FIG. 21C, a photoresist film 217 is formed only on a part of polycrystalline silicon layer 206 corresponding to the channel region. BF.sub.2, for example, is introduced into polycrystalline silicon layer 206 by ion implantation using photoresist film 217 as a mask. Then, photoresist film 217 is removed, and heat treatment is carried out so that boron is diffused in polycrystalline silicon layer 206. A source region 206a and a drain region 206b are formed by this.
A SRAM is characterized by smaller power consumption as compared with that of a DRAM. Therefore, a SRAM is used in portable type computer or word processor, an IC card, and the like, apart from general electronic equipment. These portable products are used with batteries, so that the power consumption of a SRAM must be made lower.
In the case of a conventional SRAM using a high resistance load type memory cell, it is necessary to increase the resistance value of a load in order to reduce the power consumption. However, if the resistance value is increased, there is the disadvantage that the stability of a memory cell is lowered, and the stored contents are changed. On the other hand, in the case of a SRAM using a memory cell adopting a TFT as a load transistor, there is the advantage that both of low power consumption and stability of a memory cell can be achieved. Therefore, a SRAM with a high performance is provided by providing a TFT with a high performance. In order to provide a TFT with a high performance, it is necessary to provide a TFT having characteristics as described in the following.
As illustrated in FIG. 19, source region 206a of the TFT also serves as power supply interconnection line Vcc. Therefore, it is necessary to suitably lower the electrical conduction resistance of the source region. In order to achieve this, it is necessary to raise the impurity concentration of the source/drain regions of the TFT. However, if the impurity concentration of the source/drain regions is made higher, the electric field at the junction of the channel region and the drain region becomes stronger, more electrons tend to flow from the drain region to the channel region, so that the leakage current is increased, and this is a problem. If the leakage current in OFF state of a TFT constituting a load transistor is increased, current for holding the state of storing data, i.e. power consumption during waiting is increased. In other words, the drain current in the case where a TFT constituting a load transistor is in OFF state is increased. On the other hand, if the impurity concentration of the source/drain region is lowered for reducing the leakage current, there is a problem of higher electrical conducting resistance of the interconnection region constituting the power supply interconnection line or the like, which deteriorates the operational performance of the SRAM. As described above, when a p-channel TFT is applied to a CMOS-type SRAM memory cell, it is necessary to make the leakage current in the nonoperating state of the TFT as small as possible for making power consumption during waiting as small as possible.
Referring to FIG. 16A, when memory cell node N1 has a potential at "High" level, and memory cell node N2 has a potential at "Low" level, driver transistor Q3 is in OFF state, and driver transistor Q4 is in ON state. At this time, a potential at "Low" level is applied to the gate electrode of load transistor Q5 implemented with a p-channel TFT, so that load transistor Q5 is in ON state. A potential at "High" level is applied to the gate electrode of load transistor Q6 implemented with a p-channel TFT, so that load transistor Q6 is in OFF state. Memory cell node N1 is charged from power supply Vcc through load transistor Q5 in ON state, so that its potential is kept at "High" level. Leakage current is supplied from power supply Vcc through load transistor Q6 in OFF state to memory cell node N2, so that its potential is kept at "Low" level. Thus, data can be held.
In this case, driver transistor Q3 in OFF state is implemented with a bulk-type n-channel MOS transistor formed on a semiconductor substrate, so that leakage current is generated in driver transistor Q3 because of generation of a noise charge caused by alpha rays or the like from the outside. Therefore, the potential of memory cell node N1 is a little lower than "High" level. In order to counteract the effects of generation of the noise charge, it is necessary to increase the current supplied for keeping the potential of memory cell node N1 at "High" level, i.e. the drain current of load transistor Q5 in 0N state. Accordingly, when a load transistor is implemented with a p-channel TFT, it is necessary to form the TFT so that the drain current during operation is as large as possible for stabilizing the data holding characteristic.
Furthermore, as illustrated in FIG. 21C, the positional relation between gate electrode 204 of a p-channel TFT and source/drain regions 206a, 206b is determined by the position of photoresist film 217 formed by a photolithography technique. Therefore, there is a problem that source/drain regions 206a, 206b cannot be formed in a self-align manner with gate electrode 204. | {
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The polygalactomannans are polysaccharides composed principally of galactose and mannose units and are usually found in the endosperm of leguminous seeds, such as guar, locust bean, honey locust, flame tree, and the like. Guar flour, for example, is comosed mostly of a galactomannan which is essentially a straight chain mannan with single membered galactose branches. The mannose units are linked in a 1-4-.beta.-glycosidic linkage and the galactose branching takes place by means of a 1-6 linkage on alternate mannose units. The ratio of galactose to mannose in the guar polymer is, therefore, one to two. Guar gum has a molecular weight of about 220,000.
Locust bean gum is also a polygalactomannan gum of similar molecular structure in which the ratio of galactose to mannose is one to four. Guar and locust bean gum are the preferred sources of the polygalactomannans, principally because of the commercial availability thereof.
Polygalactomannan gums swell readily in cold water and can be dissolved in hot water to yield solutions which characteristically have a high viscosity even at a concentration of 1-1.5 percent. Guar gum and locust bean gum as supplied commercially usually have a viscosity (at 1% concentration) of around 1000 to 4000 centipoises at 25.degree. C using a Brookfield Viscometer Model LVF, spindle No. 2 at 6 rpm.
There are various rigorous applications that require greater stability under variable conditions than is provided by hydrocolloid gums that are commercially available. For example, it is desirable that a gum which functions as a protective colloid or gelling agent in oil well drilling mud compositions and oil well fracturing compositions exhibit a degree of solution stability and heat stability under operating conditions.
Further, solutions of ordinary hydrocolloid gums are not sufficiently stable under variable conditions of pH and temperature or not sufficiently stable in the presence of polyvalent metal ions to qualify for application as explosive gelling agents or as oil well acidizing media, and the like.
Accordingly, it is an object of this invention to provide high viscosity hydrocolloid gum compositions which exhibit solution stability and heat stability under conditions of low pH.
It is another object of this invention to provide highly acidic gels of polygalactomannan gums which are suitable as explosive gelling agents and as oil well acidizing media.
It is a further object of this invention to provide a novel process for producing dimensionally stable gels of polygalactomannan allyl ether gums.
Other objects and advantages shall become apparent from the following description and examples. | {
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Field of the Invention
The present invention relates to a manufacturing method of a diffraction grating.
Description of the Related Art
An Echelle diffraction grating made of a crystal material is a diffraction grating configured to generate diffracted light of a high order, and machining in a ductility mode is required to form grating grooves for a good optical characteristic. A critical cutout thickness exists in the boundary between the ductility mode and a brittle mode. For example, JP 2003-075622 proposes to form the grating grooves in Si or Ge crystal through superfine cutting using a single crystal diamond tool by setting the processed surface to a (111) plane and a cutting direction to the inside of the (111) plane.
However, no prior art propose machining to form the grating grooves in the Echelle diffraction grating made of a CdTe or CdZnTe crystal material, or a stable ductility mode even when a crystal orientation (crystal plane azimuth) and a critical cutout thickness are set to parameters. When the Echelle diffraction grating is used to as a transmission type (immersion type, backside reflection type), it is easily conceivable that its optical performance is affected by both of the long side and the short side. Nevertheless, in common use, the light incident direction is arranged perpendicularly to the short side of the sectional shape of the grating, and thus the quality of the short side is critical as well as the reflective type. | {
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The present invention relates to deterring entry of birds to spaces where their presence can be causative of damage to property or possible harm and annoyance to persons therein and, refers more particularly to a device which establishes a bird incursion deterring magnetic field at a space.
Bird presence in certain spaces such as agricultural fields, environs of dwellings, parks, commercial areas and certain industrial sites can be undesirable for numbers of reasons. For example, birds can feed on agricultural plants to the destruction or harm of plant growth. Birds at spaces where people gather such as parks, commerce centers and outdoor meeting places often are unwelcome visitors with regard to leavings which can strike people, stain automobiles and create unsightly appearance on buildings. Also, there are occasions when the presence of birds can be an annoyance to people engaged in relaxation pursuits at and about a dwelling, recreational area and the like.
Ways and means of dealing with this problem are known. In my earlier filed laid open Japanese U.M. applications 1-146881 and 4-650086, there is disclosed use of magnets to establish a magnetic field at spaces to be protected from bird intrusion, these being, for example, hemispherical magnets hung from ropes erected near spaces to be protected. These magnets are utilized in line with the understanding that magnetic field presence of a certain value can create a discomforting physiological response in birds moving into the orbit or influence of the field and such that a bird thus discomforted will fly off to escape the discomfort effect.
The magnet use described in these applications is that where numbers of the magnets are mounted at fixed locations in pattern thought to best provide field coverage for a given space. The numbers of magnets needed can be high for the purpose sought and thus can in instances represent bothersome interference with a person's quite enjoyment especially when used, for example, on a terrace or balcony of a dwelling.
It is because of disadvantages as noted above, that more effective and efficient use of these devices be provided, e.g., reduce the magnet numbers needed while enlarging the effectiveness of the magnets that are used. | {
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1. Field of Invention
The disclosed invention pertains to the device designed for the racking of billiard balls, specifically, the racking of billiard balls in a diamond-shaped configuration as well as many non-conventional configurations. It is specifically designed to remedy the inherent problems with the currently-available billiard racks of the balls not racking tightly and balls being moved or disturbed upon removal of the rack. Currently, the majority of billiard racks are one-piece devices and fit relatively loosely over the billiard balls, which does not rack the balls tightly. Players normally attempt to use their fingers to force a tighter arrangement. Also, with the currently-available racks being one piece, removing the rack without disturbing the balls is almost impossible. The optimal goal is for each billiard ball to be in direct contact with each other. Tight racking of the balls is of the utmost importance to a good and true break of the balls.
There is a need for a billiard ball rack which is simple in its design and construction, yet superior in its function. The present invention will accomplish these goals and provide additional multi-ball racking capabilities of multiple configurations.
2. Description of the Prior Art
All billiard games require the tight racking of the billiard balls (all balls touching each other.) Numerous popular billiard games are described in the “Billiard: The Official Rules &Records Book” published by the Billiard Congress of America. This book describes in great detail the rules for playing 7-ball, 9-ball and poker pool. It explains the equipment (diamond-shaped racks) that is needed to play these games, and also emphasizes the need to have the balls tightly racked. All currently-available billiard racks are one-piece apparatuses and therefore have the inherent problems as previously stated above of loosely-racked balls. Another billiard game described in “Official 16-Ball Rules and Regulations,” copyright 2004, 16-Ball, Inc., also racks billiard balls into a 16-ball, diamond-shaped configuration.
The great majority of currently-available billiard racks are one-piece, triangular-shaped or diamond-shaped devices. They support a very limited number of billiard ball-racking configurations and, therefore, a limited number of billiard games. The great majority of billiard games being played today, i.e., 8-ball, 9-ball, have changed little since the early 1900s. The currently available diamond-shaped racks are one-piece devices and support only one configuration.
The current invention, being a two-piece device allows for a multitude of non-conventional configurations, one of which is demonstrated in FIG. 4. The current invention, therefore, opens the door to the creation of new, innovative billiard games with multiples of different numbers of billiard balls and different configurations. | {
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Alkanolamine sweetening units are used for the removal of H.sub.2 S and CO.sub.2 from natural gases, enhanced oil recovery gases, refinery hydrodesulfurizer recycle gases, FCCU and Coker gas plant tail gases, LPG streams, and Claus sulfur recovery tail gases. The alkanolamines commonly used are ethanolamine, diethanolamine, methyl diethanolamine, diisopropanol amine, and triethanol amine. These compounds are weak bases in water solution. When solutions of alkanolamines are contacted in packed, sieve plate, bubble cap, or valve tray columns with streams containing H.sub.2 S and CO.sub.2, the H.sub.2 S and CO.sub.2 dissolve into the alkanolamine solution. The following chemical reactions then take place: ##EQU1##
The solution of water, unreacted alkanolamine, and alkanolamine salts are subjected to steam stripping to decompose the alkanolamine salts and remove H S and CO.sub.2 from the alkanolamine. The H.sub.2 S and CO.sub.2 removed from the alkanolamine can then be processed by Claus sulfur recovery, incineration, fertilizer manufacture, or other means.
H.sub.2 S and CO.sub.2 are not the only gases in the above referred to streams which form weak acids when dissolved in water. Other such acid gases, as they are commonly called, that may appear in gas streams treated with alkanolamine include SO.sub.2, COS, or HCN. These gases also undergo the same reactions as H.sub.2 S and CO.sub.2 to form alkanolamine salts. These salts, though, cannot be removed by steam stripping as are H.sub.2 S and CO.sub.2 salts. Thus, they remain and accumulate in the system.
Another problem is presented if oxygen gets into the alkanolamine system. Oxidation of acid gas conjugate base anions leads to the formation of other alkanolamine salts, most commonly salts of thiosulfate (S.sub.2 O.sub.3.sup.-2), sulfate (SO.sub.4.sup.-2), thiocyanate (SCN.). Other inorganic acid anions, such as, chloride (Cl.sup.-) may also be present. These salts also cannot be regenerated by steam stripping.
Alkanolamine salts which cannot be heat regenerated, called heat stable salts, reduce the effectiveness of alkanolamine treating. The alkanolamine is protonated and cannot react with either H.sub.2 S or CO.sub.2 which dissolve into the solution. Also, accumulated alkanolamine salts are known to cause corrosion in carbon steel equipment which is normally used in amine systems. The salts are also known to cause foaming problems which further decreases treating capacity.
The normal procedure used to deprotonate the alkanolamine, so it can react with H.sub.2 S and CO.sub.2, is to add an alkali metal hydroxide, such as NaOH, to the amine solution. The deprotonated alkanolamine then can be returned to H.sub.2 S and CO.sub.2 removal service. However, the sodium salts of the anions of the heat stable salts are also heat stable, are difficult to remove and thus accumulate in the alkanolamine solution, with attendant corrosion and foaming problems.
In one process, the alkanolamine solution containing heat stable alkali metal salts is contacted with a basic anion exchange resin to remove the heat stable anions from the solution and thereafter the solution is contacted with an acidic cation exchange resin whereby alkali metal ions are removed from the solution. Anions of any heat stable alkanolamine salts are also removed by the basic anion exchange resin. Removing the heat stable salts in this manner reduces foaming losses. corrosion and maximizes the alkanolamine concentration.
The basic anion exchange resin used in the described process is regenerated by flushing with water to remove free alkanolamines, followed by elution with dilute sodium hydroxide to displace heat stable salt anions with hydroxide ions and a second water wash to remove residual sodium hydroxide and sodium slats. The acidic cation exchange resin is regenerated by flushing with water to remove free alkanolamine, followed by elution with dilute hydrogen chloride to displace sodium cations with hydrogen ions. A second water wash is then used to remove residual hydrogen chloride and sodium chlorides.
In the described process alkanolamine in the alknaolamine solution is protonated by hydrogen at the ionic sites on the acidic cation resin and becomes attached to these sites as alkanolamine cations. When the cation resin is regenerated with the dilute HCl solution, both alkali metal cation and such alkanolamine are displaced from the resin, with hydrogen ions taking their place. The alkanolamine in the regenerant stream cannot be returned to the alkanolamine circulating system for reuse because the alkali metal and chloride ions in the regenerant would recontaminate the system. The resultant loss of alkanolamine is unacceptable both economically and environmentally. | {
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Conductive pads are located over a top of an interconnect structure in order to provide electrical connections to a separate die, package or interposer for forming a three-dimensional integrated circuit (3DIC). In order to reduce the risk of oxidation of the conductive pads, passivation layers are deposited over the conductive pads.
As technology nodes decrease, a pitch between conductive pads decreases. As a result, passivation layers having a higher degree of conformity, i.e., uniform thickness of the passivation layer, are used to protect the conductive pads. In some instances, the passivation layers are formed using a high density plasma chemical vapor deposition process (HDPCVD). HDPCVD generates charged particles and these charged particles are directed toward the conductive pads during deposition of the passivation layer over the conductive pads. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a secondary battery.
2. Description of the Related Art
A lithium ion secondary battery includes a core pack having a bare cell and a protection circuit module (hereinafter, referred to as a ‘PCM’).
The bare cell includes a positive electrode plate, a negative electrode plate, an electrolyte, and a separator, supplies electrical energy to electronic devices, and is charged and discharged repeatedly during its lifetime. The PCM protects the secondary battery from over-charge and over-current, and prevents the secondary battery from decreasing performance due to over-discharge.
The bare cell and the PCM are assembled into a battery pack in such a way that the PCM is positioned on a side or on an upper surface of the bare cell having electrode terminals. When the PCM is positioned at a side of the bare cell, the relative placement results in a more complicated packaging. The shape of the side of the bare cell, possible interference between the side of the bare cell and devices mounted on a lower surface of the PCM, and the manner in which the PCM is coupled to the bare cell all complicate the packaging. | {
"pile_set_name": "USPTO Backgrounds"
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Currently, memory packages, such as dual, in-line memory modules (DIMM) may reside on both sides of a printed circuit board (PCB) or other substrate. This increases memory density for the system. Signals for the memories may route through the substrate, which may have several layers. With memory packages on both sides of the substrate, signal routing and integrity may become an issue.
Signals being routed through the substrate may connect to balls or connections to the DIMM on opposite sides of the packages. For examples, signals going to the closest side of the package on the one side of the substrate will generally end up having to go to the farthest side of the package on the other side of the substrate. The DIMM for the other side of the package is turned ‘upside down’ to mount it on the other side, causing the relevant connection to be on the other side of the package from the signal origination. | {
"pile_set_name": "USPTO Backgrounds"
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Databases have become the subject of significant recent interest, not only because of the increasing volume of data being stored and retrieved by computerized databases, but also by virtue of the data relationships which can be established during the storage and retrieval processes. Most of the interest in databases has concerned user demands for an improved ergonomic interface.
One aspect of improved ergonomics is the ability to recover a database in an efficient manner when a computer failure occurs. In the past, entire backups of a database were often used to restore a database from a particular point in time. However, as more and more information was stored in a database, and the information changed more often, archival of the entire database became less desirable and incremental changes were used to recover a database. An example of this approach to database recovery is shown in U.S. Pat. No. 4,592,086 and IBM TDB no. 4a, Sept. 1991, pp. 24-26, entitled, BACKWARD RESTORE FROM INCREMENTAL BACKUP. The article and patent describe an incremental backup methodology and how a database can be restored from incremental backup tapes. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention generally relates to a write-once-read-many (WORM) optical disk, and more particularly to a write-once-read-many optical disk being able to perform high density recording in a wavelength range that is no greater than blue laser wavelength.
2. Description of the Related Art
In recent years and continuing, development of blue laser, which enables ultra-high density recording, is rapidly growing. Furthermore, write-once-read-many type optical disks are being developed along with the rapid development of blue laser.
In the conventional write-once-read-many type optical disk, a laser beam is irradiated to a recording layer formed of an organic material so as to form recording pits in the recording layer (the recording pits mainly formed by change of refractive index created by decomposition/alteration of the organic material). Accordingly, the optical constant and decomposition behavior of the organic material used in the recording layer are important elements for forming satisfactory recording pits.
It is, therefore, necessary to select a material having suitable optical property with respect to blue laser wavelength and decomposition behavior. That is, for the purpose of increasing reflectivity in an unrecorded state, and/or for the purpose of creating a considerable change of refractive index by decomposing the organic material by irradiating laser thereto (thereby obtaining a large degree of modulation), the recording/reproduction wavelength is selected so that it is situated at a bottom of a long wavelength side of a large absorption band.
This is because the bottom toward the long wavelength side of the large absorption band of the organic material is a wavelength area in which a suitable absorption coefficient and a large refractive index can be obtained.
Nevertheless, with respect to blue laser wavelength, there is hardly any organic material providing an optical property with a value equivalent to that of a conventional recording layer. In order to obtain an organic material having an absorption band in the vicinity of the blue laser wavelength, the molecular structure is to be reduced or its conjugated system is to be shortened. This, however, leads to decrease of absorption coefficient (light absorption function), that is, decrease of refractive index.
In other words, although there are many organic materials having absorption bands in the vicinity of the blue laser wavelength range and although it is possible to control absorption coefficient, such organic materials do not have a large refractive index and are unable to attain a sufficient modulation degree (degree of modulation).
Patent Documents 1-5 (corresponding to Japanese Laid-Open Patent Application Nos. 2001-181524, 2001-158865, 2000-343824, 2000-343825, and 2000-335110) are examples showing the organic materials used for blue laser. However, in the embodiments of these documents, merely the solution and spectrum of the thin film are measured. There is no description regarding a recording/reproduction operation in these documents.
Although there are some descriptions regarding recording/reproduction in the embodiments of Patent Documents 6-8 (corresponding to Japanese Laid-Open Patent Application Nos. 11-221964, 11-334206, and 2000-43423), the recording wavelength thereof is 488 nm. Furthermore, the documents do not describe the conditions for recording or the density of recording but merely describe that satisfactory recording pits can be formed.
Although there are some descriptions regarding recording/reproduction in the embodiment of Patent Documents 9 (corresponding to Japanese Laid-Open Patent Application No. 11-58955), the recording wavelength thereof is 430 nm. Furthermore, the document do not describe the conditions for recording or the density of recording but merely describe that satisfactory degree of modulation can be obtained.
Furthermore, although a recording wavelength of 430 nm and a NA of 0.65 are described in the embodiments of Patent Documents 10-19 (corresponding to Japanese Laid-Open Patent Application Nos. 2001-39034, 2000-149320, 2000-113504, 2000-108513, 2000-222772, 2000-218940, 2000-222771, 2000-158818, 2000-280621, and 2000-280620), the recording is conducted with a low recording density (same recording density as DVD) in which the shortest pit is 0.4 μm.
Although a recording/reproduction wavelength of 405-408 nm is described in the embodiment of Patent Document 20 (corresponding to Japanese Laid-Open Patent Application No. 2001-146074), the embodiment does not specifically describe the recording density, but merely describes a low recording density in which 14T-EFM signals are used for recording.
Therefore, the above-described documents show that there is hardly any organic material that is able to provide an optical constant equal to the optical constant desired for a recording layer of a conventional write-only-read-many optical disk, in the vicinity of the 405 nm (center area of the oscillation wavelength of the blue semiconductor laser employed in current practical use).
Furthermore, there is no example which clearly defines the recording conditions in the vicinity of a wavelength of 405 nm and records with a recording density higher than that of DVD.
Furthermore, in a write-only-read-many optical disk employing a conventional organic material, the main absorption band of the organic material is situated in the vicinity of the recording/reproduction wavelength. Therefore, the dependency of the optical constant of the organic material with respect to wavelength becomes greater (thereby causing complex refractive index δn and/or δk to change considerably even when there is only a slight change of wavelength δ λ, see FIG. 1). Therefore, this leads to a problem where reflectivity, and recording characteristics, such as recording sensitivity, modulation degree, jitter, and error rate to change considerably when change of recording/reproduction wavelength occurs due to, for example, individual differences amongst lasers or change in ambient temperature.
Meanwhile, from the aspect of reducing the cost and energy for developing pigments, Patent Document 21 (corresponding to Japanese Laid-Open Patent Application No. 2002-74740), describes an optical recording medium having a pigment with a maximum absorption that is situated toward a long wavelength compared to the wavelength of light beam employed for writing. However, the difference between this example and the present invention is described below.
Conventionally, it is typical for a write-only-read-many optical disk to have a High-to-Low recording property. Therefore, it is necessary to select an organic material, such as a pigment capable of providing a complex refractive index that is substantially equal to that of a conventional recording layer. However, since the typical organic material for short wavelength has a small molecular structure, there are few parts to which a substituent having a donor/acceptor effect can be applied. Furthermore, even in a case where the molecular structure is large, the substituent is unable to sufficiently provide the donor/acceptor effect since the conjugated system is short.
Therefore, in a case of a recording/reproduction wavelength area that is no greater than that of a blue laser, it is extremely difficult to obtain a complex refractive index that is substantially equal to that of a red laser wavelength area. Furthermore, even if there is an organic material that is able to provide a complex refractive index that is substantially the same as that of the red laser wavelength area, it is extremely difficult to optimize the complex refractive index of the organic material to the recording/reproduction wavelength.
Furthermore, in a conventional exemplary case of realizing a High-to-Low recording property, the absorption band of the organic material layer is set to be situated toward the short wave side with respect to the recording/reproduction wavelength range, and the recording/reproduction wavelength is set to be situated at the bottom of the absorption band of the organic material layer. However, under these conditions, there is a problem in which the organic material layer requires to be designed in accordance with the selection of the recording/reproduction wavelength and a problem in which the recording/reproduction property considerably changes with respect to the change in the wavelength of the laser during recording/reproduction. | {
"pile_set_name": "USPTO Backgrounds"
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The invention applies to a system for braking the moving elements of a focal plane shutter for a photographic camera, with the braking system becoming effective just before the moving elements reach their stop or end position. Such focal plane shutters usually have thin and lightweight metal blades that are combined in an overlapping arrangement to form a shutter curtain, and the shutter can include one element that moves to open the shutter and another element that moves to close the shutter. Such moving shutter parts require considerable spring force in spite of their relatively small mass and inertia, and the spring forces have to be effective over the entire extent of the picture window throughout the entire distance of travel of the shutter elements to make the slot speed exact throughout its distance of travel. This requires braking of a considerable amount of energy as the shutter elements approach their stop positions, and the braking force is relatively abrupt in stopping the shutter elements.
Brake systems for abrupt stopping of shutter elements moving at the focal plane are generally known. Among others, it is already shown in German Pat. No. 1,090,508, issued Mar. 23, 1961, to brake the moving elements of a focal plane shutter by a belt brake that is similar to a drum brake. Such a belt brake applies a predetermined brake torque to a brake drum that is operatively connected with shutter curtain parts in a coupling that includes a coil spring, an engaging drum, and a forked lever. The coupling mechanism only operates in one direction, as a known coil spring coupling and transmits brake torque of the drum brake to the shutter curtain during braking operations and then uncouples the brake spring of the drum brake to prevent unreasonably high shutter cocking forces. Such an arrangement requires relatively complex coupling devices, and its coupling coil spring is subject to variations in slip that are changed by external influences so that it is not completely reliable and also occupies considerable space.
The invention involves recognition of the problems of prior art braking systems for focal plane seutters and a realization of a way of providing a braking system that operates reliably and effectively and also gently and smoothly in braking the moving elements of a focal plane shutter without causing any bumpings or vibrations. The invention also combines these virtues with a compact brake system that requires little space, is simple, efficient, and effective, and provides a braking torque that is conveniently adjustable and capable of accurately establishing the end or stop positions of the shutter elements (blade overstroke). | {
"pile_set_name": "USPTO Backgrounds"
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Computerized role-playing games (RPGs) have secured their place in the video game industry as one of the most popular video game types. The attraction typically comes from a mixture of the overall story (or stories) being told in the game, and the underlying game mechanics (e.g., how the characters are improved as the game progresses, how battles are conducted, etc.). In some RPGs, this mixture involves the use of two distinct types of scenes. A first scene, sometimes referred to as a map scene, is intended to show the game player an overall world in which the story (or a current portion thereof) takes place. The map scene may, as its name implies, resemble a topographical map, and may include the various cities, towns, deserts, bodies of water, forests, etc. that exist in the RPG world (or the current portion of the RPG world).
The player's character (which may include a party of multiple individuals), may be represented on the map scene as an icon, and the player may move the character icon around the map to visit different locations in the game's environment. Moving the character through the map scene allows the player to explore the RPG world, and may be a helpful way of moving the story forward.
As the player navigates through an RPG map, many RPGs provide for encounters between the player's character and other entities and/or objects not under the player's control (e.g., the player may encounter a wandering band of thieves). A second type of scene, sometimes referred to as a battle scene, is often used to present such encounters. Using a separate scene may allow for a more dynamic and engaging experience, as the player is shown an up-close view of the battle taking place, and may be given a different variety of actions that can be taken in the battle scene (e.g., certain fighting actions may be available in the battle scene, and the battle scene may show objects that might not be depicted on the map scene due to scale).
There have been two approaches to initiating these encounters from the map scene. In one approach, the map scene depicts icons that represent enemies and/or objects with which the player's character could interact. Such a map scene used a single icon to represent a group of enemies, and when the player character's icon interacted with the enemy icon, the game displayed a transition to a battle scene involving the player's character (or party) and the enemies represented by the icon. This approach helps to simplify the map scene, but also makes it more difficult for the player to anticipate the type of encounters that will occur. A player may be surprised to find that the enemy icon represented a larger number of enemies, or more difficult enemies, than expected, and the player might not enjoy the resulting battle.
In another approach, enemies are simply not shown on the map scene. Encounters in these types of games may appear to the player to occur at random, since the player has no warning in the map scene. This approach may further simplify the map scene, and the surprise nature of the encounters may make for a more exciting game experience, but the player's inability to anticipate, initiate, or avoid the encounter may also lead to some player frustration. | {
"pile_set_name": "USPTO Backgrounds"
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Cleaning compositions and methods for removing water insoluble organic materials which employ dibasic ester solvents are known in the art. For example, U.S. Pat. No.'s 4,934,391 and 4,927,556 teaches emulsions of dibasic esters and water, but generally, simple emulsions lack the stability to remain dispersed over long periods of time.
U.S. Pat. No.'s 5,080,831 and 5,080,822 teach true solutions of non-hydrocarbon and non-hydrogenated hydrocarbon organic solvents having water solubilities of from 0.2 to 6% in a combination of water and a solubilizer.
U.S. Pat. No. 5,158,710 teaches a microemulsion of non-hydrocarbon and non-hydrogenated hydrocarbon organic solvents having water solubilities of from 0.2 to 6% with a solubilizing additive, a builder and optionally a coupler. In this patent the builder is a material that enhances the cleaning efficiency of the surfactant by inactivating water hardness, supplying alkalinity to assist in cleaning and buffering the pH of the composition so that it remains above 7.
Other patents relating to emulsions and/or microemulsions include U.S. Pat. No. 5,597,792 which teach an oil continuous microemulsion of water, organic solvents and a surfactant; U.S. Pat. No. 2,606,874 which teaches a hydrocarbon oil emulsion using a C7 or higher alkanediol; and U.S. Pat. No.'s 4,781,848 which teaches hydrocarbon microemulsions for metal roll forming.
Microemulsions have properties that make them attractive for consideration in the formulation of cleaning products. The object of the present invention is to provide a microemulsion characterized in that it has a wide range of compositional and thermal stabilities and that can, without loss of identity as a microemulsion, be combined with solvents and additives for formulation into various cleaning compositions. | {
"pile_set_name": "USPTO Backgrounds"
} |
As process technology scales down to below 30 nm, it becomes challenging to develop memory devices (e.g., flash memories) with a smaller geometry due to worsening transistor reliability and characteristics such as retention and endurance. Moreover, the cost for developing every next generation of process technology increases enormously. Against this background of factors, through-silicon-via (TSV) technology reveals itself as a good candidate to overcome scaling limits, and increase memory capacity without diminishing performance or increasing costs. Fundamentally, TSV technology involves methods for using short vertical interconnects through stacked dies, thereby implementing semiconductor devices with a 3-dimensional structure. TSV technology may thus provide significant benefits including high density, high bandwidth, low power consumption and small form factor.
The following publications provide additional background material related to TSV technology and are hereby incorporated by reference herein: J. Burns, et al., “Three-Dimensional Integrated Circuits for Low Power, High-Bandwidth System on a Chip,” ISSCC Dig. Tech. Paper, pp. 268-269, February 2001. P. E. Emma, E. Kursun, “Is 3D chip technology the next growth engine for performance improvement?” IBM J. Res. & Dev. 52, No. 6, 541-552, November 2008. Gabriel H. Loh, “3D-Stacked Memory Architectures for Multi-Core Processors,” 35th ACM/IEEE International Conference on Computer Architecture, June 2008. R. Patti, “Three-Dimensional Integrated Circuits and the Future of System-on-Chip Designs,” Proc. of the IEEE, vol. 84, no. 6, June 2006. W. Topol, J. D. C. La Tulipe, L. Shi, et al., “Three Dimensional Integrated Circuits,” IBM Journal of Research and Development, vol. 50, no. 4/5, pp. 491-506, July/September 2006. Uksong Kang, et al., “8 Gb 3D DDR3 DRAM Using Through-Silicon-Via Technology,” ISSCC Dig. Tech. Paper, pp. 130-131, February 2009.
Two main types of TSV technology are “Via First” and “Via Last”. Depending on the type of TSV technology, either reactive-ion etching (RIE) or laser drilling is performed before a TSV metallization process (TSV formation). TSV implementation using RIE and Via First has been discussed in M. Kawano, et al., “A 3D Packaging Technology for 4 Gbit Stacked DRAM with 3 Gbps Data Transfer,” IEEE IEDM Dig. Tech. Papers, pp. 581-584, 2006, hereby incorporated by reference herein. Additionally, TSV implementation using laser drilling and Via Last has been discussed in Uksong Kang, et al., “8 Gb 3D DDR3 DRAM Using Through-Silicon-Via Technology,” ISSCC Dig. Tech. Paper, pp. 130-131, February 2009. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present disclosure relates to a headphone ear cup and more particularly, to a headphone ear cup having a composite cover which includes different regions with different air permeability, such that the headphone ear cup of the present disclosure can have excellent air-permeable property and improved acoustic field effect.
2. Description of the Related Art
A traditional headphone ear cup is substantially annular in shape and connected with a surface of a speaker unit of a headphone, and usually comprises an annular cushion and a cover covering the annular cushion.
Most of the existing covers of the traditional headphone ear cup are made of a single material. Specifically, in order to isolate the ambient sound as far as possible to enable a user to clearly hear the sound from the speaker unit through the sound hole of the headphone ear cup, i.e. to establish a satisfied acoustic field, the cover of the traditional headphone ear cup is made of a single material with high isolation but low air permeability, thereby sacrificing the air-permeable property of the cover. As such, the user may feel uncomfortable after using the traditional headphone ear cup with air-tight cover for a long time. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to the purification of immunoglobulins. In particular, the invention relates to the purification of monoclonal antibodies by high performance liquid chromatography on the basis of variations in light chain structure.
Purified preparations of monoclonal antibodies are often difficult to obtain since fluids from which they are purified are frequently contaminated with antibodies of unknown specificity. Although conventional chromatographic procedures often yield purified immunoglobulin fractions as analyzed by SDS-PAGE, the presence of contaminating antibodies of the same class cannot be ruled out. Therefore, time-consuming techniques are often necessary to properly analyze purified immunoglobulin fractions. An ideal procedure for the analysis of monoclonal antibody preparations should be fast, reproducible and easy to perform. Further, it should be useful for both analytical and preparative purposes. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a biomagnetic field measurement apparatus intended to detect a magnetic field mainly generated from a brain.
In a magnetoencephalograph for measuring a magnetic field (cerebral magnetic field) generated from a brain, a large number of pick-up coils are arranged over the whole-head surface with the object of mapping the electrophysiological activity of cerebral nerves. The magnetoencephalograph of this kind is called whole-head type magnetoencephalograph because the pick-up coils are arranged so as to cover the whole head for the purpose of measurement (see, for example, Patent Document 1). A merit of the whole-head type magnetoencephalograph is that signals of the whole cerebral hemisphere can be measured simultaneously. In other words, mapping of exciting regions becomes possible. For example, abnormally exciting regions in epilepsy can be discriminated by mapping the exciting regions.
There is also an example in which a plurality of adiabatic mechanisms each including means for measuring biomagnetism such as a SQUID sensor are arranged and the adiabatic mechanisms are driven respectively singly (Patent Document 2).
In the conventional biomagnetic field measurement apparatus used for magnetocardiography measurement or magnetoencephalography measurement, a method of detecting magnetic signals of an object living body by using pick-up coils each formed of a superconducting wire and transmitting the magnetic signals to superconducting quantum interference devices (hereafter abbreviated to SQUIDs) is adopted. The pick-up coils have the function of removing noise caused by an environmental magnetic field and improving the signal to noise ratio. As for the biomagnetic measurement and the pick-up coils, there is detailed description in Non-Patent Document 1. [Patent Document 1] JP-A-07-297456 [Patent Document 2] JP-A-2002-336211 [Non-Patent Document 1] S. J. Williamson and L. Kaufman, Journal of Magnetism and Magnetic Materials 22 (1981), 129-201. | {
"pile_set_name": "USPTO Backgrounds"
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In chromatography the output from a chromatograph is called a chromatogram. Generally, a chromatogram is a hard-copy plot of detector output voltage versus time. Ideally, the voltage would appear as a Gaussian-shaped peak, or series of such peaks. For qualitative analytical applications of chromatography, it is essential to know the retention time, i.e., the elapsed time from the start of the chromatogram to the maximum voltage of the peak. For quantitative analysis with a chromatograph it is necessary to know the retention time and the area under the voltage-time peak.
In the current practice of chromatography, the measurement of retention times and peak areas is generally done by electronic integrators. Such chromatographs usually provide hard-copy records of peak areas and retention times in suitable units.
Under ordinary conditions the chromatographer has no method available, other than standard sample injection, to calibrate the output of the integrators. Even with standard sample injection, it must be assumed that the chromatograph is functioning properly.
It is therefore a specific aspect of the present invention to provide apparatus useful in calibrating the output of such chromatographs. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to a semiconductor integrated circuit constructed with MOS transistors, and more particularly to a latch circuit and a shift register, which are used in the output stage of an image memory.
2. Description of the Related Art
An operation speed of the image memory is very high. For example, a cycle time of the image memory is approximately several tens ns. A latch circuit for the data outputting must be operable at a high speed and with a good reliability.
A conventional data output latch circuit in use with an image memory is as illustrated in FIG. 1. The latch circuit is comprised of first latch section 10 and second latch section 20. First latch section 10 includes clocked inverter 11 controlled by a pair of clock signals .phi. and .phi., and flip-flop 14 coupled at the input terminal with the output terminal of clocked inverter 11. Flip-flop 14 is made up of complementary type inverter 12 and clocked inverter 13. Clocked inverter 13 is coupled at the input terminal with the output terminal of inverter 12 and at the output terminal with the input terminal of the inverter, and is controlled by a pair of clocked signals .phi. and .phi.. Second latch section 20 includes clocked inverter 21 controlled by clock signals .phi. and .phi., and flip-flop 24 connected at the input terminal with the output terminal of clocked inverter 21. Flip-flop 24 is made up of complementary type inverter 22 and clocked inverter 23. Clocked inverter 23 is connected at the input terminal with the output terminal of inverter 22, and at the output terminal with the input terminal of the inverter, and is controlled by clock signals .phi. and .phi.. Input signal Vin is directly input to latch section 10. Input signal Vin is also input to latch section 20, after passed through and inverted by inverter 25. The output terminal of latch section 10 is connected to the gate of N channel MOS transistor 27 as a load transistor, which partially constitutes output circuit 26. The output terminal of latch section 20 is connected to the gate of N channel MOS transistor 28 as a drive transistor.
The details of latch section 10 or 20 are illustrated in FIG. 2. Clock signal .phi. is applied to the gate of N channel MOS transistor QN2 as a switching transistor for clocked inverter 11 and the gate of P channel MOS transistor QP4 as a switching transistor for clocked inverter 13. Clock signal .phi. is applied to the gate of P channel MOS transistor QP2 as a switching transistor in clocked inverter 11 and the gate of N channel MOS transistor QN4 as a switching transistor in clocked inverter 13.
The operation of the data output latch circuit of FIG. 1 thus arranged will be described.
In a first period, clock signal .phi. is in high ("H") level and clock signal .phi. is in low ("L"level. Clocked inverters 11 and 21 execute the inverter operation, to invert and delay input signals Vin, and produce output signals Q and Q.
In a second period, clock signal .phi. is changed from "H" to "L" in logical level, and clock signal .phi. is changed from "L" to "H". Clocked inverters 11 and 21 do not execute the inverter operation, while clocked inverters 13 and 23 execute the inverter operation. As a result, the data thus far output are stored in flip-flops 14 and 24.
In a third period, clock signal .phi. is "L" in logical level and clock signal .phi. is "H" in logical level. At this time, flip-flops 14 and 24 are operating, and hence continue to store the data therein. In this case, clocked inverters 11 and 21 do not operate. Accordingly, output signals Q and Q remain unchanged, even if input signal Vin varies.
In a fourth period, clock signal .phi. is changed from "L" to "H", and clock signal .phi. is changed from "H" to "L". Clocked inverters 13 and 23 do not operate, while clocked inverters 11 and 21 operate to execute the inverter operation. Then, the latch sections 10 and 20 fetch new input signal Vin, and substantially simultaneously output the contents of the input signals, i.e., the data stored therein as output signals Q and E,ovs/Q/ .
A sequence of the operations of the first to fourth periods is repeated.
A timing chart illustrating the sequence of operations of the FIG. 1 circuit is shown in FIG. 3.
As described above, the conventional latch circuit uses the clocked inverters. Use of the clocked inverters needs opposite phase clock signals .phi. and .phi. controlling this inverter. Practically, however, it is very difficult to generate the clock signals which are exactly out of phase in a continuous manner. To form such clock signals, a clock signal must be passed through an inverter. When passing through the inverter, the clock signal inevitably delays by some time-length. Therefore, the clock signal and the inverted clock signal propagate and reach a point at different times. If such staggered clock signals are applied to the clocked inverter, the clocked inverter is placed in a high impedance state during a transient period that the input-signal outputting mode is changed to the output-signal holding mode. This high impedance state is peculiar to the clocked inverter. In such a high impedance state, the output data is possibly inverted, leading to a malfunction operation of the inverter.
Why the high impedance state occurs in the clocked inverter and what the phenomenon brings about, will be described below.
In FIG. 2, when input signal Vin is 37 H", clock signal .phi. is "H", and inverted clock signal .phi. is 37 L", MOS transistors QN1, QN2, and QP2 are turned on, while transistors QP1, QP4 and QN4 are turned off. Accordingly, node NA is "L", transistor QP5 is turned on, and transistor QN5 is turned off, output Q provides an "H" level signal, transistor QP3 is turned off, and transistor QN3 is turned on.
If clock signals .phi. and .phi. are both "L" while input signal Vin is kept high, then MOS transistors QP1, QP3 and QN2, and QN4 are turned off, and transistors QP2, QP4, QN1 and QN3 are turned on. Under this condition, both the clocked inverters 11 and 13 do not operate, and node NA is at high impedance. At the initial stage in the operation, node NA maintains the previous potential, i.e., "L" level. At this time, the transistors QP2 and QP4 in the clocked inverter are in an on state. If the potential at node N3 is high, the high potential is transferred to node NA, so that the potential at node NA goes high. If the potential increase is large, transistor QP5 is turned off, and transistor QN5 is turned on. Finally, the logical state at output Q is inverted.
When input signal Vin is "L", clock signal .phi. is "H", and clock signal .phi. is "L", MOS transistors QP1, QP2 and QN2 are turned on, and transistors QN1, QN4 and QP4 are turned off. Accordingly, the potential at node NA goes high. Transistor QP5 is turned off, and transistor QN5 is turned on. Output Q provides an "L" level signal. Then, transistor QP3 is turned on and transistor QN3 is turned off.
While input signal Vin maintains the "L" state, clock signals .phi. and .phi. go high. Then, MOS transistors QP1, QP3, QN2 and QN4 are turned on, and transistors QP2, QP4, QN1 and QN3 are turned off. Under this condition, clocked inverters 11 and 13 do not operate, and node NA is at a high impedance. At the initial stage in the operation, node NA maintains the previous potential, i.e., an "H" state. At this time, the transistors QN2 and QN4 in the clocked inverter are in an on state. If the potential at node N4 is low, the low potential is transferred to node NA, so that the potential at node NA goes low. If this potential drop is large, MOS transistors QP5 is turned on, and transistor QN5 is turned off. Finally, the logical state of the data at output Q is inverted.
Latch sections 10 and 20 are followed by output circuit 26, as shown in FIG. 1. Output circuit 26 is made up of N channel MOS transistor 27 as a load transistor and N channel MOS transistor 28 as a drive transistor. The gates of these transistors 27 and 28 are controlled by the output signals Q and Q of latch sections 10 and 20. With such a circuit arrangement, when the output potential is inverted as described above, load transistor 27 and drive transistor 28 are both in an on state, so that a rush-current flows between the power source terminals. With this rush-current, the power dissipation is greatly increased, particularly when the memory device including the output circuit operates at a high speed. This further provides an instable power source voltage of the device.
Further, even if clock signals .phi. and .phi. are perfectly opposite phase, and the level variations simultaneously occur at both the outputs Q and Q, it is impossible to prevent the rush-current from flowing in the output circuit 26 during this transient period.
Particularly in the image memory in which the serial access is performed with a short cycle time, the increased power dissipation due to the rush-current is not negligible. | {
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1. Field of Invention
The present invention relates to an attachment for a front-end loader, and, more particularly, is directed to an attachment device which can be readily connected and disconnected to the bucket of a front-end loader in thereby converting the bucket loader for other uses.
2. Description of the Prior Art
A front-end loader, often referred to as a bucket loader, is a widely used, commonly known piece of equipment found in many commercial and industrial applications, such as in construction and excavating operations, as well as in many agricultural applications, such as in farming and livestock operations. Bucket loaders are of various sizes and configurations, but basically include a prime mover, such as a tractor or the like, having a pair of pivotally supported lift arms that are hydraulically driven to raise and lower a bucket attached to the ends of the lift arms. Normally, a hydraulic cylinder is also used to pivot the bucket about a horizontal axis so as to move the bucket from a load receiving to a load discharging position, and vice versa. The primary use or function of a bucket loader is to transfer bulk materials, such as sand, gravel, earth, manure, etc., from one location to another. For example, bucket loaders are used in livestock operations for scooping manure from the livestock pens and loading same on a spreader, while in construction operations a bucket loader is used to load gravel from a pile onto a dump truck.
Due to the large investment of a bucket loader and for convenient reasons, it has been common practice to convert bucket loaders to perform operations other than the transferring of bulk materials. This practice adds versatility to the loader and thereby eliminates the need and associated costs for using separate pieces of equipment or tools to perform these separately desired operations.
One example of such a converted use of a bucket loader is illustrated by U.S. Pat. No. 3,249,245 (Foster) wherein there is shown a converter unit that attaches to the bucket of the loader in thereby providing an auxiliary tongue or hitch for towing machinery from the front of the bucket loader. The Foster converter unit includes a rigid, forwardly projecting, beam which has its rear end pinned to the rear wall of the bucket and with its forward end being supported above the floor of the bucket by a vertical column and a pair of diagonal support members. The lower end of the column and the support members are provided with slotted brackets that engage fore-and-aft extending fork tines which are disposed adjacent the floor of the bucket. The cooperation of the slotted brackets in engagement with the fork tines in conjunction with the pin connection of the beam to the rear wall provide the necessary attachment for supporting the converter unit on the bucket.
Another type of bucket loader converter can be seen in U.S. Pat. No. 3,587,887 (De Carli). Shown is a converter unit that converts the bucket loader from a bulk material handling device to a boom structure device adapted to raise and lower construction pipe into a drainage trench. This converter device is similar to the one shown in the above Foster 3,249,245 patent being comprised of a rigid beam which is attached to the rear wall of the bucket by a pin and which further includes two forwardly projecting support members secured to the forward end of the rigid beam with lower ends that are slotted or so shaped to receive therebetween the floor of the bucket. Again, the pin connection of the rigid beam to the rear wall along with the slotted engagement of the support members with the floor provide the necessary attachment of the converter unit on the bucket.
Although not necessarily limited thereto, the converter units set forth in both the Foster 3,249,245 and DeCarli 3,587,887 patents are examples of bucket loader converters typically found in commercial industrial applications.
Another area where bucket loader conversion units are commonly found is in farming and livestock operations. With the recent advent and enormous popularity of the round bales, the need by farmers and livestock operators for a specific tool to handle and transport these large round bales produced by the round baler was created. In response to this need, several different types of round bale handling machines and devices were introduced into the market place. Some of these large round bale handlers are large, bulky, complex and expensive machines capable of transporting several large round bales at one time, whereas, other bale handlers are more simple in structure, being less costly, and usually transport only one large round bale at a time. Generally, these latter bale handlers cooperate or work in conjunction with another piece of machinery or tool which the farmer or livestock operator already has on his farm, such as a pick-up truck, a tractor, a front-end or bucket loader.
One example of such a large round bale handler can be seen in the Cox patents (U.S. Pat. Nos. 4,015,739 and 4,099,629). Cox's bale handler is of the type which operates in conjunction or combination with the three-point hitch of a farm tractor or can be operated on the bed of a pick-up truck. U.S. Pat. No. 4,179,034 shows another type of round bale handler that is designed to be used in combination with a pick-up truck.
U.S. Pat. No. 4,120,404 is illustrative of still another type of round bale handler. Shown is an attachment structure having three spear-shaped bale engaging prongs and which is designed to be attached either to the three-point hitch of a tractor or to a front-end loader that is mounted on the tractor. For attaching the bale handling device to the front-end loader, the bucket must first be removed and then the bale handler attaches to the lift or boom arms of the loader.
Yet another type of round bale handler is seen in U.S. Pat. No. 3,921,837. The round bale handler shown here is adapted for assembly with the bucket of the loader and basically includes a pair of forks that are attached by brackets to the sidewalls of the bucket.
The above-described commercial and agricultural bucket loader conversion units or attachments all suffer from various shortcomings. Although some of these conversion attachments have advantages over other ones and certain ones have specific disadvantages, it can be concluded that there exists a need for an improved bucket loader conversion attachment which can easily and quickly be connected to and disconnected from the bucket loader without first removing the bucket so as to readily convert the bucket loader for other uses. The uses may include, but are not limited to, the handling of large bales, the maneuvering of drainage pipe or the like in a construction operation, or the moving of equipment from one location to another as is customarily performed by a machinery dealer that moves his machinery about the machinery lot for one reason or another. | {
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The invention relates to the general field of dual damascene wiring in integrated circuits with particular reference to maximizing conductance of the vias.
The term xe2x80x98damascenexe2x80x99 is derived from a form of inlaid metal jewelry first seen in the city of Damascus. In the context of integrated circuits it implies a patterned layer imbedded on and in another layer such that the top surfaces of the two layers are coplanar.
The introduction of damascene wiring solved several problems that faced the semiconductor industry as wiring grew ever smaller and more complex. A damascene structure is, by definition, planarized, possible leakage problems due to incomplete coverage of wiring by inter metal dielectrics are eliminated, and rapid diffusers such as copper or silver can be more reliably confined by diffusion barriers.
Referring now to FIG. 1 we show layer 11 of silicon oxide which covers a partially completed integrated circuit (not shown). Embedded in layer 11 is a layer of metal 12 that fills a trench previously formed in the surface of 11 so that the top surfaces of 11 and 12 are co-planar.
In the standard process for contacting layer 12 through a double damascene structure the next steps are illustrated in FIG. 2. Silicon nitride layer 13 is deposited over the surfaces of 11 and 12 followed by silicon oxide layer 21. This, in turn, is followed by a second silicon nitride layer in which a via hole opening has been etched prior to over coating with a second silicon oxide layer 23. Also seen in the figure is a photoresist pattern 24 which will be used to define the trench that will carry the next layer of damascene wiring.
FIG. 3 illustrates the appearance of the structure after etching where via hole 31 extends all the way down to layer 12 and connects at its upper end to trench 32 which extends through layers 22 and 23. An important step to complete this structure is the deposition of barrier layer 42, which can be seen in FIG. 4, and which coats the walls of trench 32 as well as the walls of via hole 31 and the exposed upper surface of wiring layer 12. The trench and via hole are then over filled with copper layer 43 and the surface planarized giving the appearance shown in FIG. 4. Layer 41 of silicon nitride is the equivalent of layer 13 for this level of wiring.
It is important to note that the thickness of layer 42 is a compromise between providing adequate diffusion resistance and minimal electrical resistance. Although the barrier layer material is electrically conducting, its resistivity is relatively high so it increases resistance between the two levels of wiring (12 and 43) both because of contact resistance at the interface to 12 and because it occupies a significant portion of the total cross-section of the via hole, thereby reducing the amount of copper available to contribute to the conductance of the via.
During a routine search of the prior art no references that teach the process or structure of the present invention were encountered. Several references of interest were, however, found. For example, Lin (U.S. Pat. No. 5,753,967) deals with the problem of how to center the stud part of a dual damascene structure relative to the trench part. He teaches a self-aligned technique wherein the trench is first formed then given a coating of dielectric which serves as a hard mask for the formation of the stud opening.
Mu et al. (U.S. Pat. No. 5,612,254) describe formation of a dual damascene structure. First the metal stud portion is fully formed in a first dielectric layer. Then, a second layer of dielectric is deposited and the trench portion is aligned and formed therein. In one embodiment, there is a layer of silicon nitride between the two dielectrics but this does not extend into the stud region.
Ireland (U.S. Pat. No. 5,466,639) describes the procedure, detailed above, that has become the xe2x80x98standardxe2x80x99 process for forming a dual damascene structure.
Shoda (U.S. Pat. No. 5,689,140) teaches the use of two different adhesion layers in the stud and trench portions of a damascene structure. As a result, when the trench and stud get filled with metal, growth on the upper (trench) adhesion layer does not begin until growth in the lower (stud) portion is well along. Materials of choice for the first adhesion layer include a metal, silicon, and silicides. For the second adhesion layer, preferred materials include metal nitrides, metal borides, and metals.
It has been in object of the present invention to provide a process for forming a dual damascene structure.
A further object on the invention has been that said dual damascene structure provide low via hole resistance between wiring levels without sacrificing the effectiveness of the diffusion barrier.
These objects have been achieved by means a structure in which the via hole is first lined with a layer of silicon nitride prior to adding the diffusion barrier and copper. This allows use of a barrier layer that is thinner than normal (since the silicon nitride liner is an effective diffusion barrier) so that more copper may be included in the via hole, resulting in an improved conductance of the via. A key feature of the process that is used to make the structure is the careful control of the etching process. In particular, the relative selectivity of the etch between silicon oxide and silicon nitride must be carefully adjusted. | {
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The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Some hybrid vehicles may include an electrical circuit between a motor/generator and a power control unit having an inverter. A busbar may connect to electrical terminals of the motor and inverter terminals of the power control unit, thereby forming the electrical circuit between the two components. Power may be supplied from a battery to the motor by utilizing the electrical circuit, and generated power may be supplied to the battery from the generator. A current sensor may be attached to the busbar to measure the current flowing in the busbar, and feedback current control may be performed based on comparison of that measured value with a current instruction value. The motor may then be controlled at a desired revolution rate and torque with the power control unit.
However, the busbars may be a single-threaded terminal design. As such, the busbars may be rigid and not allow for the adjustment of tolerances in the electrical circuit during assembly. Moreover, multiple busbar connectors may be required, which increases packaging size and assembly time. Accordingly, while such conventional electrical circuits work for their intended purpose, it is desirable to provide an improved system that provides an adjustable interconnection during assembly. | {
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Each year the number of mobile devices increases, and their performance is also increasing. The pace of development of battery production technologies is not keeping up with the rate of growth of the power consumption of mobile devices, so that modern smartphones and tablets usually need to be charged every day, or sometimes several times a day. As a result, charging stations or kiosks for powering the batteries of mobile devices are becoming increasingly more common—they are situated in convenient public places and are free of charge. One of the most popular data and power transmission interfaces may include USB. However, in certain cases the USB port at charging stations may not be connected to a power adapter, but to a computer system, usually a computer. The danger in this case is the possible transmission of confidential data from the mobile device, as well as the possibility of infecting the mobile device with malicious software from the computer connected to such a USB port.
There are certain adapters and cables only supplying power to mobile devices and blocking data transmission. Some adapters may have a built-in microcontroller for additional analysis and filtering of data being transmitted. However, if a user needs to connect a mobile device to an unknown computer in order to transmit data (such as upload photographs onto a computer for the printing of photographs), he may need to disconnect the adapter which is blocking the data transmission or disconnect the filtering of the data being transmitted in the adapter with a built-in microcontroller. At the same time, some such computers may present a danger of which the user is unaware.
Accordingly, there is a need to protect data on a mobile device when interacting with a computer. | {
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(1) Field of the Invention
The present invention relates to a heavy duty pneumatic radial tire. More particularly, the invention relates to an improvement of durability of the heavy duty pneumatic tires for use under a high speed and a high internal pressure, for instance, aircraft radial tires and super high speed train radial tires.
(2) Related Art Statement
With the high performance of automobiles and the consolidation of the roads, the radial structure of the tires has been recently been progressively adopted and the percentage of the radial structure has been increasing. However, in the case of the aircraft tires and the super high speed train tires, the structural innovation of the tires are slow, and much have not examined therefor up to now, probably because of consideration upon the safety. Nevertheless, while the social demand for energy saving and the demand for the fuel mileage improvement have recently become greater, weight-reducing need in the tire parts has been also getting larger and larger. From this point of view, radial tires using aromatic polyamide fiber cords instead of steel cords as tire reinforcement have been examined. In particular, it is anticipated that a large scale of weight reduction can be accomplished by using aromatic polyamide fibers as high tenacity and high modulus cords in the carcass plies.
However, there is a big problem in the use of the aromatic polyamide fibers in the plural carcass ply layers. In other words, the fibers having high tenacity and high modulus possess the problems that the fibers have inactive molecular motion with respect to heat and are difficult to thermally shrink. For this reason, when a tire is produced by using such plural ply layers, the ply cords positioned in the inner layer or layers are likely to meander. This results in local unwinding of the twisting cords. Further, such a phenomenon is likely to occur particularly at a shoulder portion and a bead portion at which deformation of the tire is larger. This is because a bending operation is generally necessary in forming the plural carcass plies during the production of the tire, and difference in cord passing distance occurs in the inwardly positioned carcass cord layer or layers. On the other hand, in the case of the cords of fibers made of rayon, polyester, nylon, or the like as the material of the general use tire cords, no such meandering occurs because they thermally shrink during the vulcanization. Further, in the case of the conventionally used aromatic polyamide fibers, there is a problem that the cords are cut due to fatigue during use at portions where the cords are locally unwound. Therefore, tires merely employing the aromatic polyamide in the plural carcass layers can not be practically used. | {
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The present invention relates to novel substituted derivatives of quinoxaline. More particularly, the invention relates to such derivatives which are useful as therapeutic agents, for example, to effect reduction in intraocular pressure, to increase renal fluid flow and to effect an alteration in the rate of fluid transport in the gastrointestinal tract.
Various quinoxaline derivatives have been suggested as therapeutic agents. For example, Danielewicz, et al U.S. Pat. No. 3,890,319 discloses compounds as regulators of the cardiovascular system which have the following formula: ##STR2## where the 2-imidazolin-2-ylamino group may be in any of the 5-, 6-, 7- or 8- position of the quinoxaline nucleus; X, Y and Z may be in any of the remaining 5-, 6-, 7, 8- positions and may be selected from hydrogen, halogen, lower alkyl, lower alkoxy or triflucromethyl; and R is an optional substituent in either the 2- or 3- position of the quinoxaline nucleus and may be hydrogen, lower alkyl or lower alkoxy. | {
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A major problem in relation to drug preparation, drug administration or other similar handling of pharmaceuticals is the risk of medical and pharmacological staff being exposed to drugs or solvents which may escape into ambient air. The problem is particularly serious when hazardous drugs such as cytotoxics, antiviral drugs, antibiotics and radiopharmaceuticals are concerned. Other hazards may arise when taking samples relating to virus infections or the like. For these reasons, systems for handling and administrating drugs and other medical substances under improved safety conditions have been developed.
U.S. Pat. No. 4,564,054 (Gustavsson) discloses a fluid transfer device for preventing air contamination when transferring a substance from a first vessel to a second vessel. The device is attached or connectible to the vessel and comprises a first member, in which a piercing member e.g. a needle, provided with a passage is enclosed. The first member has a sealing member e.g. a membrane, through which the needle can be passed. The device further comprises a second chamber, which is detachably connectable to the first member and which also has a sealing member, e.g. a membrane. When the first and second members are connected to each other, the two sealing members are located in a position with respect to each other so that they can be penetrated by the piercing member which is movable with respect to the sealing member.
The sealing members are resilient liquid and gas-proof barriers having the ability of sealing tightly after penetration and retraction of the piercing member to prevent leakage of liquid as well as gas components.
Another example of a device using a barrier member is found in U.S. Pat. No. 3,900,028 in which is disclosed an injection site arrangement for a vessel having a first cylindrical member interposed in a second cylindrical member and a barrier member arranged between the first and second members. During manufacturing of the injection site arrangement, the second member is telescopically inserted into an opening at a lower end of the first member. The barrier member is tightly compressed in the longitudinal direction of the first and second members. The first cylindrical member is thereafter fixed to the second cylindrical member by means of a rib on the first cylindrical member and a corresponding groove an the second cylindrical member. The rib of the first cylindrical member is formed by deformation of the lower edge of the first cylindrical member by subjecting it to heat and pressure during the manufacturing of the injection site arrangement.
The barrier members used in the protective systems are usually made from a resiliently compressible material such as a natural or synthetic rubber or a rubber like material. However, it has been found that medical devices such as those mentioned above have certain limitations.
Resilient barrier members are commonly made from a thermoplastic elastomeric polymer material (TPE) allowing the members to be affixed in a protective injecting device by ultrasonic welding. The ultrasonic welding procedure is temperature dependent and has to be carefully controlled as the manufacturing tolerances are small. Consequently, production of the prior art protective injection devices is complicated and costly. The barrier members are mounted in the protective injecting devices with a predetermined amount of tensioning compression. The amount of tension applied to the barrier member is critical. If the barrier member is too highly tensioned, it may result in the piercing member punching out a piece of the membrane when the membrane is penetrated. On the other hand, if the tensioning of the membrane is too low, the injection site will not close completely after removal of a piercing member. Accordingly, mounting of the resilient barrier members requires a carefully controlled process.
A further problem is that resilient barrier members are subject to aging and may loose some of the production induced tension over time.
It has been suggested in WO 2010/127691 A1 to apply the resilient barrier member between two parts of a protective injection device. A first part of the protective injection device in WO 2010/127691 A1 is a connecting part for connecting the device with a medical appliance such as a vial and the second part is a tensioning part that can be locked in engagement with the first part with the resilient barrier member clamped between the two parts. In the interlocked position of the parts, the resilient barrier member is subjected to a working tensioning force.
The protective injection device in WO 2010/127691 A1 has been found to work very well in diminishing the problems with aging and production tolerances. An objective with the present invention is to offer a further improved protective injection device. | {
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Semi-trailer trucks often include one or more fairing panels that extend downwardly from an area near the bottom of the cab or sleeper portion of the vehicle. These panels increase the aerodynamic efficiency of the vehicles, thereby improving fuel economy and reducing operating costs. The panels also improve the aesthetics of the vehicles by concealing vehicle components, such as fuel tanks, fluid lines, frame components, etc., that would otherwise be visible.
FIG. 1 shows a typical fairing under-cab installation for a known semi-trailer truck. The vehicle 10 includes a chassis frame 12 supported by a plurality of wheels 14. A cab 16 is located on a forward end of the frame 12 to provide a vehicle operator with an enclosure from which to operate the vehicle 10. An optional sleeper 18 extends from a rear portion of the cab 16 to provide sleeping quarters and a living space for the vehicle operator. A fairing panel 20 is mounted to the vehicle frame 12 to extend downwardly from an area just below the cab 16 and the sleeper 18.
The cab 16 and the sleeper 18 are mounted to the frame 12 with a suspension in order to provide a smoother ride for the vehicle operator. As a result, relative motion necessarily occurs between the cab 16 and the frame 12 and between the sleeper 18 and the frame 12 during vehicle operation. Because the fairing panel 20 is mounted to the frame 12, relative motion also occurs between the cab 16 and the fairing panel 20 and between the sleeper 18 and the fairing panel 20. To accommodate this relative motion, the fairing panel 20 is mounted to the frame 12 so that a gap 22 exists between the fairing panel 20 and the cab 16 and between the fairing panel 20 and the sleeper 18. The gap 22 allows the cab 16 and the sleeper 18 to move relative to the frame 12, and thus the fairing panel 20, during vehicle operation. This in turn prevents unwanted contact between the fairing panel 20 and the cab 16 and/or sleeper 18.
While the above-described fairing system provides improved aerodynamic efficiency and improved vehicle aesthetics, the gap between the fairing panel and the cab and sleeper causes undesirable aerodynamic drag. Further, the gap allows structure that would ideally be concealed to be visible from outside of the truck. Owners and operators of semi-trailer trucks would find it desirable to provide a fairing assembly that eliminates this gap, thereby improving both the aerodynamic efficiency and the appearance of the vehicle. | {
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Liquid oral pharmaceutical compositions for oral administration have been often formulated in the past in vehicles which contain ethanol. Frequently, the compositions thusly prepared do not contain water because of a stability problem, to suppress undesirable organoleptic properties of the composition or to enhance solubility.
Ibuprofen is a non-steroidal anti-inflammatory (analgesic) drug whose family is known in the art as NSAID's. It has been on the ethical and proprietary markets for years and is in widespread use. While many dosage unit forms of the compound are on the market, few acceptable oral, one phase liquid forms of the compound are on the market, few acceptable oral, one phase liquid forms of ibuprofen have been reported. U.S. Pat. Nos. 4,684,666, and 3,228,831 and U.K. Patent Specification 971,700, are representative of the prior art.
Due to the low solubility of ibuprofen in aqueous vehicles and its poor organoleptic characteristics, certain of us earlier found excellent oral dosage units can be prepared using a vehicle comprising certain edible oils and absolute ethanol. However, now a new problem has been identified.
Ibuprofen, and other NSAID's which have a reactive carboxylic acid moiety in their chemical structures, have been unexpectedly found to form ethyl ester derivatives in the oral edible oil-alcohol vehicle.
Esterification can reduce the quantity of ibuprofen available for absorption. The alcohol-oil vehicles remain, however, excellent products organoleptically when formulated with NSAID active ingredients. The following description will describe a solution we have found to this previously unrecognized problem in the art. | {
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Liver fibrosis is the common response to chronic liver injury, ultimately leading to cirrhosis and its complications, portal hypertension, liver failure and hepatocellular carcinoma. The fibrogenic process is consecutive to intense proliferation and accumulation of hepatic myofibroblasts that synthesize fibrosis components and inhibitors of matrix degradation (Friedman, S. L., J Biol Chem 275, 2247-50 (2000)).
Cannabis Sativa contains over sixty compounds, the most active of which is (−) Δ9-tetrahydrocannabinol (THC). Endogenous natural cannabinoids have also been characterized, anandamide and 2-arachidonyl glycerol, which are arachidonic acid-derived lipids (Piomelli, D et al, Trends Phamacol Sci 21, 218-24. (2000)). Cannabinoids bind to two G protein-coupled receptors, CB1 and CB2, that equally bind THC (Pertwee, R. G., Curr Med Chem 6, 635-64. (1999)). CB1 is thus one of the two known cellular receptors for cannabinoids. This receptor being a G protein-coupled transmembrane receptor is known to be expressed in brain and blood vessels (Pertwee, R. G., Curr Med Chem 6, 635-64 (1999)) but not in hepatocytes (Guzman, M & Sanchez, C., Life Sci 65, 657-64 (1999)). CB1 mediates the psychoactive effects of cannabis. In contrast, CB2 receptors are mainly expressed in the immune system and are devoid of psychoactive effects (Friedman, S. L., J Biol Chem 275, 2247-50 (2000)). In addition to their psychotropic effects, cannabinoids display analgesic, antiemetic and orexigenic central effects (Harrold, J. A. & Williams, G. Br J Nutr 90, 729-34 (2003)). Moreover, cannabinoids also elicit anti-inflammatory and vasorelaxing properties (Kumar, R. N., Chambers, W. A. & Pertwee, Anaesthesia 56, 1059-68. (2001)). Several studies also suggest that cannabinoids may be potential antitumoral agents, owing to their ability to induce the regression of various types of experimental tumors, including glioma or skin tumors. These antitumoral effects are mainly attributed to their antiproliferative and apoptotic properties (Bifulco, M. et al., Faseb J 29, 29 (2001); Casanova, M. L. et al., J Clin Invest 111, 43-50. (2003); Sanchez, C. et al., Cancer Res 61, 5784-9. (2001)).
There are only few data concerning the hepatic action of cannabinoids. CB1 and CB2 receptors are not expressed in hepatocytes (Guzman, M. & Sanchez, C. Life Sci 65, 657-64 (1999)). However, CB1 receptors are present in endothelial cells isolated from hepatic arteries, and their expression increase during cirrhosis (Batkai, S. et al. Nat Med 7, 827-32. (2001)).
Two isoforms of the receptor CB1 have been isolated: a long isoform (corresponding to SEQ ID NO:1) and a shorter one truncated in the NH2 terminal part corresponding to a splice variant (corresponding to SEQ ID NO:2), which differ in their affinity for their ligands (Shire et al., J Biol Chem, (1995); Rinaldi-Carmona et al, J Pharmacol Exp Ther (1996)). There also exist 5 single nucleotide polymorphisms in the coding region of the CB1 receptor gene. Of these only three result in single amino acid changes to the CB1 receptor (these being, in SEQ ID NO:1, a Phenylalanine to Leucine substitution at position 200, an Isoleucine to Valine substitution at position 216 and a Valine to Alanine substitution at position 246 and the corresponding positions in SEQ ID NO:2). A consensus 7-domains sequence for the CB1 receptor exists which is strongly conserved in vertebrates but does not appear in other cannabinoid receptors (Attwood, T. K. and Findlay, J. B. C., Protein Eng 7(2) 195-203 (1994), Attwood, T. K. and Findlay, J. B. C., 7TM, Volume 2 Eds G. Vriend and B. Bywater, (1993), Birnbaumer, L., Ann. Rev Pharmacol Toxicol, 30, 675-705 (1990), Casey, P. J. and Gilman, A. G., J. Biol. Chem. 263(6) 2577-2580 (1988), 5. Attwood, T. K. and Findlay, J. B. C, Protein Eng 6(2) 167-176 (1993), Watson, S, and Arkinsall, S, In The G Protein-Linked Receptor Factsbook, Academic press, 1994, PP 80-83). That consensus amino acid sequence comprises the 7 protein domains of SEQ ID NO:3 to SEQ ID NO:9.
Antagonists to the receptor CB1, which include reverse or inverse agonists, have been previously described. These include the substituted amides described in WO03/077847, the substituted aryl amides described in WO03/087037, the substituted imidazoles described in WO03/063781, bicyclic amides described in WO03/086288, the terphenyl derivatives described in WO 03/084943, the N-piperidono-3-pyrazolecarboxamide and N-piperidino-5-(4-chlorophenyl)-1-(2,4-dichlorophenyl)-4-methylpyrazole-3-carboxamide described in EP-B-656354, the aryl-benzo[b]thiophene and benzo[b]furan compounds respectively described in U.S. Pat. No. 5,596,106 and U.S. Pat. No. 5,747,524, the azetidine derivatives described in FR2805817, 3-amino-azetidine described in FR2805810, or the 3-Substituted or 3,3-disubstituted 1-(di-((hetero)aryl)-methyl)-azetidine derivatives described in FR2805818. These documents are incorporated herein by reference. Other antagonists are commercially available such as N-(piperidin-1-yl)-1-(2,4-dichlorophenyl)-5-(4-iodophenyl)-4-methyl-1H-pyrazole-3-carboxamide, known commercially as AM251 and the compound known as LY-320135.
Uses of these CB1 receptor antagonists are known for the treatment of sexual dysfunction (patent application WO 03/082256), or diarrhoea (patent application WO 01/85092), or neuro-inflammatory diseases or substance abuse disorders, obesity, asthma, constipation (patent application WO 03/077847).
Documents U.S. Pat. No. 5,939,429, WO 03/077847, WO 03/084930, WO 03/084943, WO 03/063781 and WO 03/087037 disclose that CB1 antagonists can reverse the systemic hemodynamic alterations in rats with cirrhotic portal hypertension. | {
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1. Field of the Invention
The present invention lies in the field of techniques for integrating at least one distributed feedback (DFB) semiconductor laser and a passive strip waveguide.
2. Description of the Prior Art
A method for integrating a DFB laser coupled with a passive strip waveguide on a substrate is disclosed in IEEE Journal of Quan. Electronics, Vol. QE-13, No. 4, April 1977, pp. 220-223. By this method, in a first epitaxy step, an n-Ga.sub.1-x Al.sub.x As layer forming the more deeply disposed layer (for example, having x=0.3 and a thickness of 2 .mu.m), a p-GaAs layer forming the laser-active layer (for example, having a thickness of 0.2 .mu.m), a p-Ga.sub.1-y Al.sub.y As layer (for example, having y=0.2 and a thickness of 0.1 .mu.m), and a p-Ga.sub.1-z Al.sub.z As layer forming the uppermost layer (for example, having z=0.07 and a thickness of 0.2 .mu.m), are successively grown on an n-GaAs substrate by means of conventional liquid phase epitaxy. A third order grating is produced on the uppermost layer of this layer stack by means of chemical etching with the assistance of a mask which has been produced by the use of holographic photolithography. With the exception of the region of the DFB laser, the layer stack is then chemically etched away down to the substrate, thus producing a step extending down into the substrate which separates the region of the laser-active layer from the region of the passive strip waveguide.
Two further layers, that is a p-Ga.sub.1-x Al.sub.x As layer (for example, having x=0.3 and a thickness of 2 .mu.m), and an undoped Ga.sub.1-w Al.sub.w As layer (for example, having w=0.1 and a thickness of 2 .mu.m), are then grown on the stepped surface in the second epitaxy step by means of liquid phase epitaxy under relatively fast growth conditions. The p-Ga.sub.1-x Al.sub.x As layer, which is developed as the first of the two layers, is grown within a time span of 90 seconds at 700.degree. C. with a cooling rate of 5.degree. C./minute. Under these conditions, the p-Ga.sub.1-x Al.sub.x As layer splits or cracks in the step allowing the laser output power to be effectively conducted to the undoped Ga.sub.1-w Al.sub.w As layer, thus forming the passive strip waveguide.
The long-side boundaries of the laser-active region and of the passive strip waveguide region are produced by etching the crystal away down to the substrate. The coupling between the DFB laser and the passive strip waveguide ensues by means of an end face coupling.
As may be seen from FIGS. 2 and 3 on page 221 of the above cited publication, the location of the splitting or cracking of the first layer grown during the second epitaxy step is critical because the split must be formed as precisely as possible at the location of the laser-active layer. The position of this split can only be controlled via the growth conditions utilized during the second epitaxy step.
It is a problem in the art to provide a method for integrating a DFB laser with a passive strip waveguide on a substrate so that DFB lasers coupled with passive strip waveguides can be reproducibly manufactured resulting in a high yield. Such a method needs to guarantee the exact alignment of the DFB laser and the passive strip waveguide relative to one another. | {
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The present invention deals with a method and system for improving high speed internetwork data transfers. More particularly, the invention is intended to interconnect Token ring/IP Hosts over Token ring Local Area Networks (LAN) and a Wide Area Network (WAN) by creating one way bridged path for host-to-host connections, using IP routing protocols to create the path, so that the LAN virtually enlarges till it encompasses the WAN with bridging getting everywhere.
Modern digital networks are made to operate over different transmission media and interconnect, upon request, a very large number of users and applications through fairly complex digital communication networks.
Accordingly, due to the variety of users"" profiles and distributed applications, the corresponding traffic is becoming more and more bandwidth consuming, non-deterministic and requiring more connectivity. This has been the driver for the emergence of fast packet switching techniques in which data from multimedia origin are chopped into fixed length packets (e.g. in Asynchronous Transfer Mode (ATM) type of operation) or in variable length packets (e.g. in so called Frame Relay (FR) type of operation). These packets are then transferred upon request for communication purposes between data sources and targets via so-called high speed communication networks. One of the key requirements for high speed packet switching networks is to reduce the end to end delays.
Also, due to the incredible increase of traffic, several types of networks have been installed which need to be interconnected to optimize the possibilities of organizing traffic between a source host terminal and a target host terminal, both located anywhere. This is made possible by using so-called internetworking (also referred to as internet). An internet is a collection of heterogeneous networks using a set of networking protocols (TCP/IP, i.e Transmission Control Protocol/Internet Protocol) developed to allow cooperating computers to share resources across the network. TCP/IP products are made by vendors and a fairly large number of networks of all kinds use it. Accordingly, the considered IP switching technologies may incorporate new proprietary protocols, which complicates inter-networking operations.
TCP/IP is a set of data communication protocols that are referred to as the internet protocol (IP) suite. Because TCP and IP are the best known of the protocols, it has become common to use the term TCP/IP to refer to the whole family. TCP and IP are two of the protocols in this suite. Other protocols that are part of the internet suite are User Datagram Protocol (UDP), Internet Control Message Protocol (ICMP), Address Resolution Protocol (ARP), Real Time Protocol (RTP) and Reservation Protocol (RSvP).
An Internet is a collection of heterogeneous networks using TCP/IP. The administrative responsibilities for an internet (for example, to assign IP addresses and domain names) can be within a single group or distributed among multiple groups. Networks comprising an internetwork can use either the same or different technologies.(For more information on TCP/IP one may refer to the book xe2x80x9cInternet working with TCP/IPxe2x80x9d by Douglas Comer).
Host stations attached to LANs can send messages from any of them to any other. Communication within a single (LAN) network is referred to as intranetworking, and communications between stations that are attached to different LAN networks is called internetworking. Stations within a same network can communicate directly, while internetworking communications have to go across special internetworking devices called gateways and possibly referred to as routers as they route data from one network into another.
As shall be emphasized in the following description, the routers may, in some cases be replaced by so-called bridges. Both have specific characteristics as they operate at different layers of protocols of the network.
As networks have developed, various approaches have been used in the choice of communication characteristics such as communication medium, network topology, message formats, protocols for channel access etc . . . . Some of these approaches have been converted into standards. A model of these standards is known as the International Standards Organization (ISO) Open System Interconnection (OSI) model. This model specifies a hierarchy of protocol layers and defines the function of each layer in the considered network. Each layer in one station which might be a host computer or a Router/Bridge carries a conversation with the corresponding layer in another station with which communication is taking place, in accordance with the protocol defining the rules of this communication. In fact, information is transferred down from layer to layer in one host or router then through the channel medium and back up the successive layers in the other host or router/bridge (target). Accordingly, the higher the layer at which communication operations are performed, the longer and more cycle consuming the process.
IETF standardizes TCP/IP through RFCs (Requests For Comments).The three layers (out of seven) defined by the OSI Standards and to be considered here include the physical layer, the data link layer and the network layer. The physical layer is the lowest layer (i.e level 1) assigned to transmission of data bits over the communication channel. Design of the physical layer involves issues of electrical, mechanical or optical engineering, depending on the physical medium used to build the communication channel.
The layer next to the physical layer, is the data link layer (i.e. level 2). The main task of the data link layer is to transform the physical layer interfacing with the channel into a communication link that appears error-free to the next above layer, i.e. the network layer (level 3). The data link layer performs such operations as structuring data into packets or frames and attaching control information and numbers to the packets or frames to enable checking data validity and reinserting reconstructed packets at the right location into the data flow. There are two point-to-point types of connections i.e. connectionless and connection oriented connections.
Although the data link layer is primarily independent of the nature of the transmission medium, certain aspects of the data link layer functions are dependent on the transmission medium. This is why, in some network architectures, the data link layer is divided into two sublayers: a logical link control sublayer which performs all medium-independent functions of the data link layer, and Media Access Control (MAC) sublayer. The MAC sublayer determines which station should get access to the communication channel, when requests for access are in conflict. The functions of the MAC sublayer are more likely to be dependent on the transmission medium. Bridges may be designed to operate in the MAC sublayer.
As internetwork topologies become more and more complex, the number and significance of routers or bridges used to interconnect the network both increase. Consequently, the choice between these two devices for performing the interconnecting function may seriously impact the whole internetwork performance, e.g. in terms of transmission time delay.
The basic function of a bridge is to make large interconnected networks look like a single flat LAN. A bridge acts at the MAC layer and listens to all message traffic on all networks (e.g. LANs) to which it is connected, and forwards each message onto the networks other than the one from which the message was received. Bridges also maintain a database of station locations derived from the content of the messages being forwarded. After a bridge has been in operation for some time, it can associate practically every station with a particular link (i.e. path) connecting the bridge to a network (e.g. LAN) which contributes to speeding up the traffic.
There are two main types of bridges which are: Transparent Bridges (TB) and Source Route Bridges (SRB). There are also combinations of these (SRTB).
If several networks are connected by bridges and form a closed loop, a message may be circulated back to the network from which it was originally transmitted, which may flood the internetworking facility and jam the traffic. To prevent the formation of such closed loop, a so called Spanning Tree algorithm has been developed to connect the bridged networks into a tree configuration containing no closed loops. The spanning tree algorithm is executed periodically by the bridges on the interconnected network to ensure that the tree structure is maintained up-to-date, even if the physical configuration of the network changes.
While the basic advantage of the bridge (i.e. transparency to layer 3) is the rapidity of message transfers, these transfers operating at data link level (i.e. layer 2), some traffic overflow may be due to bridge transparency. For instance this is the case with TCP/IP traffic caused by so-called Address Resolution Protocol (ARP) messages made to obtain, when required, a data link layer address from the corresponding network layer address. ARP packets can be duplicated by bridges and storm the whole internetwork, possibly disrupting normal traffic flow. But as far as this invention is concerned it should essentially be recalled that bridges are transparent to broadcast messages which shall then multiply and propagate through the whole internetwork.
A router unlike a bridge, operates at the network layer level (layer 3) instead of the data link layer level, and is fundamentally meant to interconnect unlike network technologies and provide a structured address space (routing based on global address). Addressing at the network layer level, as obtained by the content of data packet address field includes a unique network identifier and a target identifier within the network. A router learns the topology of the network and builds a routing table to represent it. IP tables are established manually or through routing protocols (RIP, OSPF etc . . . ), where routers learn how to reach networks.
Routers make use of the destination network identifier in a message to determine an optimum path from the source network to the destination network. But as far as the present invention is concerned it should be noted that broadcasted messages shall be stopped by any reached router. Consequently routers provide a better isolation than bridges at the expense of processor utilization.
Thus, the network designer has to deal with conflicting situations and choose between routing and bridging operations.
Compromises to these kinds of situations have been proposed in the art. Some have an impact on source and/or target hosts software. Given the fairly wide variety of hosts already in the field no simple and unique solution to the problem raised may be proposed. Other solutions, like for instance the solution recommended by U.S. Pat. No. 5,309,437, address extended LANs and use so-called bridge-like routers including both functions. Then, depending on the type of traffic, either one of the functions is called for use. Unfortunately, during ARP operation all normal traffic is made to suffer. An improved solution to internetworking operation has been proposed in a copending European Patent Application xe2x80x9cA Method for Improving High Speed Traffic Operation in an Internet Environment and System for Implementing said Methodxe2x80x9d, filed on . . . (FR998010), and assigned to the same Assignee. This application enables speeding up internetworking by providing the network and more particularly the routers with self bridging facilities dynamically converting the used router connections into bridged connections during traffic operation. In other words, transparent bridging is performed, as required, by dynamically building up Bridge tables into the routers establishing direct level 2in-out connections. While the best mode of implementation addresses Ethernet LANs, the invention applies to routers inter-connecting most LANs, including so-called Token Ring. But as far as Token ring LANs are concerned the proposed solution is not optimal.
One object of this invention is to enable improving high speed data transfers in an internet environment by using Internet Protocol (IP) intelligence as well as Token-ring facilities to optimally drive self-bridging configuration of conventional routers.
Another object of this invention is to enable improving high speed data transfers in an internet environment by using IP intelligence and Token ring specifications to enable optimally self configuring routers into bridges, dynamically, during data traffic on the specific paths used for connections toward a designated target host.
A further object of this invention is to enable improving high speed data transfers in an internet environment requiring only limited broadcasting to enable self-configuring routers into bridges.
Another object of this invention is to provide a solution for efficiently self configuring routers into bridges on paths set between source and target hosts respectively attached to different token-rings.
The foregoing and other objects, features and advantages of this invention will be made apparent from the following more detailed particular description.
This invention deals with a method for improving high speed traffic operation in an internet environment using standardized protocols of the so-called Internet Protocol (IP) suite, by speeding up data packet transfers between a source host (S) attached to a first Token ring Local Area Network (LAN) (N1), and a target host (T) within a subnet attached to a different Token ring LAN (N2), both LANs being interconnected by a router (R) establishing connections at OSI Standard network level (layer 3) through use of an IP table, by dynamically setting, during traffic operation, a single virtual LAN.
The source host (S) encapsulates the first packet to be sent with a conventional Token ring header including RMAC as destination Media Access Control (MAC) address of R, SMAC as source MAC address and an empty Routing Information Field (RIF) as layer 2 information, and IP address of T (TIP) as layer 3 information.
Upon receiving the first packet, router R reads its IP table for best match with TIP address whereby the subnet including T is identified. The net handler runs an ARP protocol to identify TMAC address, stores it in its ARP table, substitutes MAC header with said TMAC address into said first packet destination MAC address field and forwards said first packet over N2. Router R then sends a conventional Internet Control Message Protocol (ICMP) over N1 as limited broadcast, whereby all hosts, including S, add a direct route toward T""s subnet on their interface to N1; R configuring itself in Proxy ARP for the defined subnet.
The second packet is passed by S to its N1 interface with TIP address. S runs a conventional Address Resolution Protocol (ARP) by sending an ARP request carried over an All Route Broadcast (ARB) with TIP address over N1 and R answering with RMAC address and the RIF data leading to N2. Then the second packet is sent over N1 with TMAC, SMAC, the defined RIF and TIP data.
Upon receiving the second packet, the router R bridging function identifies RIF data, and bridges the packet to its net handler toward N2. Router R""s net handler runs an ARP process to substitute R""s MAC address to TMAC address. | {
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This invention relates generally to a rapid one-reagent method for sample preparation for improved electrooptical methods for measuring human and animal erythrocyte volumes and cell hemoglobin contents. More particularly, it relates to a one step method for treating mammalian red blood cells in a sample which can be effectively measured electrooptically for determination of red blood cell volumes whereby the one-step, single reagent treatment provides isovolumetric sphering of erythrocytes in the sample independent of erythrocyte concentration in the original blood sample and without inducing lysis.
Prior art methods utilizing the measured amount of light scattered from individual red cells (erythrocytes) to determine the individual and mean volumes of red cells were subject to error for two reasons: since the native human red cell is a biconcave disc, the amount of light scattered will vary with the orientation of the cell with respect to the incident light beam; and, the shape of the cells can change during dilution and pumping steps.
For a discussion of the above, see Hemolysis and Related Phenomena, Chapter II, pp 10-49 by Eric Ponder (1948) and Transformation and Restoration of Biconcave Shape of Human Erythrocytes Induced by Amphilic Agents and Changes of Ionic Environment, Biochemica et Biophy. Acta, Bernard Deuticke, pp 494-500 (1968).
In Ornstein et al U.S. Pat. No. 4,412,004, commonly assigned, a method is disclosed and claimed which eliminates both of the above-described causes of error and permits a vastly improved method for determination of human red blood cell volumes. In the '004 patent, the inventive method involves a two-step procedure of first sphering erythrocytes isovolumetrically and then fixing isotonically. The method was devised as a two-step procedure in order to be assured that sphering had reached completion before the fixing process began, otherwise, cells might become "stiffened" by cross-linking which occurs during fixation and thus became "frozen" in some intermediate shape between the native biconcave shape and the desired spherical shape. Fixing immediately after sphering permitted the use of higher sphering agent/protein ratios in the fixing solution because cells which might otherwise lyse, were fixed before that could happen. This leads to a more convenient implementation for automated clinical use.
It has now been found, quite unexpectedly, that a single reagent containing appropriate and limited ranges of concentrations of both sphering agent and fixing agent can achieve complete isovolumetric sphering of all erythrocytes of a large range of clinical samples of blood, independently of the concentration of erythrocytes in the whole blood sample, and without inducing lysis of any of the erythrocytes in any of the diluted blood samples. It was not obvious to one of ordinary skill in the art that the employment of particular parameters in a one-step method as disclosed and claimed herein could allow for a procedure in which the speed of the sphering step remains sufficiently greater than the fixing process so that the cells are completely sphered before they have appreciably stiffened. This leads to a faster and still more convenient implementation for automated clinical use. | {
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The present invention relates to head-up displays and, in particular, it concerns a head-up display spatially aligned with the real world for a user viewing a scene through a window.
In the field of military aeronautics, it is known to provide a pilot with a head-up display (HUD). A HUD is a transparent display through which the pilot can see the real world, but which can at the same time present to him additional information, visually superimposed on the real scene. The HUD may be a cockpit-mounted device, in which case it typically covers a limited forward-looking field of view, or may be helmet mounted, in which case it is referred to as a helmet-mounted display (HMD).
In certain cases, a simple HUD system may only display data, such as the state of various aircraft instrumentation, and the location of the data in the field of view is not critical. Of more relevance to the present invention, are spatially aligned HUDs in which the display provides various symbols or other information spatially aligned to appear superimposed over, or otherwise aligned with, a corresponding object or point of interest in the scene viewed by the pilot. This allows the system to prompt the user to look in a specific direction, for example, to identify an incoming target at the limit of the visual range, or to specify what object is being tracked by a weapon system.
Implementation of a spatially aligned HUD is typically highly complex for two reasons. Firstly, complex hardware is used to measure the exact position and pose of the user's head in order to determine the alignment of the HUD with the real world as viewed by the user. Head position is typically measured by tracking the position of the user's helmet within the cockpit, either by a magnetic tracking system or by optical tracking of markers affixed to the helmet. Prior calibration procedures are required in order to determine the position of the user's eyes from the helmet tracking data.
A second reason for the complexity of HUD systems is the use of collimated optics in the display itself. In order for the content of the display to appear in focus while the user is looking at a distant scene, aircraft HUD or HMD systems typically employ an optical arrangement that makes the displayed information and symbols appear to be at infinity, known as collimated optics. This adds significantly to the complexity and weight of the display, and typically limits the available range of viewing angles. Each HUD typically can only be used by a single person at a time, requiring replication of the entire system for each user of the system.
Due to this complexity, and the accompanying costs, use of the HUD has generally been limited to military aircraft and to high-end augmented reality systems. Furthermore, the reliance on a helmet as part of the head tracking system inhibits adoption of HUD technology for various other applications.
Parenthetically, it should be noted that the literature contains many references to head-up displays in the context of automobile instrumentation. However, these HUD systems are typically not spatially aligned displays, as defined above. Techniques such as U.S. Pat. No. 6,750,832 to Peter Kleinschmidt for Information display system for at least one person teach image processing for face detection and gaze direction approximation in a vehicle. This technique teaches deflecting an illumination beam path into the field of view of the observer to display vehicle information, or information requested by the user through a user operated input device. Publication number US 2007-0262971 A1 to Stefan Hahn, Ulm, (DE) for Method and Device for Operating an Optical Display Device teaches a technique for identifying the general direction of a driver's view and varying the display of vehicle information to be compatible with this view. As previously stated, these HUD systems are not spatially aligned displays, as defined above.
There is therefore a need for a spatially aligned head-up display that is a simpler, lower-cost solution that can be used with multiple users. It is desirable that users not be constrained by equipment (such as helmets) and that it is not necessary to require the user to calibrate himself to the system prior to use. | {
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There are several shortcomings to cylindrical products in which the bore surfaces are protected against abrasion and/or corrosion by the traditional method of centrifugal casting. In the traditional method a backer cylinder or liner shell is machined with the bore diameter oversized by one-eighth (1/8) to one-fourth (1/4) inch, the surfacing alloy in powdered form and in sufficient quantity to produce the desired surface layer thickness is distributed along the bore length, the ends are capped, and then the assembly is slowly rotated while being heated to a temperature above the melting point of the surfacing alloy, at which time the assembly is rapidly rotated while being externally cooled. The backer cylinder or liner shell is most often steel and the surfacing alloys most often iron-nickel-boron-carbon for abrasion resistance, nickel-cobalt-boron-silicon for corrosion resistance, or nickel-boron-silicon-tungsten carbide for both abrasion and corrosion resistance. If multi-lobed cylindrical products are required with protected bore surfaces, they are traditionally made by first centrifugally casting the surface alloy into the required number of single cylinders, slicing these lengthwise to provide the individual lobe shapes, and fusion welding the individual cylinders to form the multi-lobed product.
These methods include:
U.S. Pat. No. 4,596,282 describes injection molding and extrusion as processes currently employed for forming articles from plastics, wherein a heated fused plastic is forced under pressure into a mold cavity to solidify in the shape and size of the cavity. The charge of plastic material to be injected into the mold cavity must be heated and pressurized prior to injection, and in one approach, the plastic starting material is fed into a hollow cylinder having a screw therethrough. As the screw turns, the plastics forced into a heated zone of the cylinder ahead of a check ring on the head of the screw, so that a predetermined volume of heated, pressurized plastic is prepared for subsequent injection into the mold cavity by a forward movement of the screw and check ring within the cylinder.
Because the economic of injection molding depends upon attainment of long operation lives for the machinery, it is important that the inner lining of the cylinder have a high resistance to wear and corrosion by the heated plastic material. Should the inside of the cylinder wear away so that the inner diameter of the cylinder is enlarged, a clearance develops between the check ring and screw, and the inner wall of the cylinder so that the plastic material leaks back from the pressurized zone, with the result that the necessary pressure for injection molding will not be developed. The cylinder must then be refurbished or replaced, or a larger diameter check ring must be utilized and, in any event, the economic production process is interrupted.
As set forth in U.S. Pat. No. 3,836,341, extruder barrels and injection molding machine cylinders have frequently been cast in recent years with high-ferrous content alloy linings. These prior ferrous alloy linings typically have ambient temperature hardness in the range of 58-64 Rockwell C in other centrifugally cast state. While such high ferrous content linings demonstrate excellent wear resistance to abrasive fillers present in plastic compositions during extrusion or molding operations, some such linings have relatively poor corrosion-resistant qualities, especially under conditions which cause the plastic material being processed to partially decompose.
Some of the disadvantages of these methods include:
(1) The surfacing alloy must have a melting temperature substantially below that of the backer shell. This severely limits the choice of surfacing alloys.
(2) The slow melting and long time for solidification of the surfacing alloy results in significant dissolution of the metal of the backer or shell and diffusion of this metal into the surface alloy. Since the shell is usually steel, this results in significant iron contamination of the surfacing alloy. In many cases the corrosion resistance of the surface is severely impaired and in some cases, such as in cylinders used for extrusion of fluoropolymers, unacceptable degradation of the polymer occurs.
(3) In the case of multi-lobed cylinders, the weld can only be made in the backer metal and can only approach but not get too close to the surfacing alloy in order to avoid cracking and spalling of the surfacing layer. This results in a gap between the two or more lobes which gap extends into the substrate metal. This allows the product being processed to penetrate the gap causing abrasion, corrosion, and product degradation.
Another special problem arises because the corrosion-resistant problem associated with high ferrous content alloy linings is particularly acute when the resin feed contains halogenated polymers or copolymers, such as fluorocarbon resins. As a result of feed degradation, which is difficult, if not impossible, to control fully the extrudate in a relatively short period of time become contaminated with minute metallic particles. These metallic particles come from the corrosive attack on the barrel lining alloy and become dislodged from the lining and migrate into the extrudate during processing. The corrosive agents are believed to be the halogens and possibly other gaseous substances formed during injection molding and extrusion.
Although nickel ingredients have been employed in varying amounts in liner alloys (see, for example, U.S. Pat. No., 3,836,341) the prior art disclosures utilized it in conjunction with substantial amounts of iron or special ingredients such as the tungsten carbide. In short, the problem is that high ferrous content liner alloys have been known to be undesirable in corrosive atmospheres, while the non-ferrous alloys proposed heretofore which exhibit satisfactory corrosion resistance, are not as wear and abrasive resistant as the high ferrous content alloys linings. Moreover, the use of special and additional ingredients such as tungsten carbide can be too costly for certain commercial applications. Nickel-based alloys often lack the requisite hardness.
One object of the present invention is to provide a method for attaining bore surface protection of cylindrical products while avoiding the difficulties or shortcomings of the previous methods.
A further object of the present invention is to provide an essentially non-ferrous alloy which is suitable as a liner for injection molding or extrusion cylinders and which is particularly adaptable for use in the surface protecting method of the inventor.
Another object is to provide a nickel-based lining alloy with improved hardness, wear resistant and corrosion resistant characteristics.
A still further object is to provide a method of lining the inner diameter of a steel housing with a nickel-based alloy, said lined steel housing being employed as a cylindrical barrel in extrusion and injection molding devices.
These and other objects of the present invention will become apparent from the ensuing description and embodiments. | {
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One image-forming device known in the art is a horizontal tandem-type color printer provided with a plurality of photosensitive drums that are arranged parallel to each other and juxtaposed horizontally (hereinafter called the “juxtaposing direction”), and a plurality of developing cartridges for respectively supplying developer to the photosensitive drums.
Of these types of color printers, a proposal has been provided for a printer having a support frame that integrally supports a plurality of photosensitive drums and a plurality of developing cartridges. The support frame can be moved with respect to the juxtaposed direction between an accommodated position and a withdrawn position. The printer also includes an intermediate transfer belt that contacts the photosensitive drums when the support frame is disposed in the accommodated position. Each developing cartridge includes a developing roller that contacts a corresponding photosensitive drum, and a toner-accommodating chamber for accommodating toner to be supplied onto the developing roller. The developing cartridges are detachably supported in the support frame and can be mounted therein and removed therefrom with respect to an axial direction of the developing rollers while the support frame is disposed in the withdrawn position. | {
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Polyethylene terephthalate (PET) has become an important raw material for production of moldings, film and fibers. Preparation of PET is described inter alia in Whinfield et al, U.S. Pat. No. 2,465,319 and in Pengilly, U.S. Pat. No. 3,047,539, and in Kirk-Othmer, Encyclopedia of Chemical Technology, Second Edition, Vol. 16, pp. 159 et seq. (1968), all disclosures being incorporated herein by reference.
Many applications for injection and extrusion molded parts require heat resistance, and it is in such applications that PET manifests certain undesirable properties. Unreinforced PET has been of limited interest for making such parts due to its low HDT (Heat Deflection Temperature)--about 75.degree. C. at 264 psi. HDT is a measure of an important thermal property of a thermoplastic material wherein a bar of the material, held in flexure under constant load (usually at 264 or 66 psi), deforms a specified amount and the temperature at which this specified deformation occurs is the HDT--see Billmeyer, Textbook of Polymer Science, p. 112, John Wiley and Sons, Inc. (1962).
U.S. Pat. No. 3,644,574 discloses blends of 1,4-butanediol polyesters with from about 1 to about 40 weight percent of a vinyl aromatic polymer (e.g., a styrenic polymer) which polymer may be inter alia, a copolymer with maleic anhydride. The blends of this patent exhibit increased HDT over the unblended polyester. However, that patent discloses at Column 1, lines 42-47 that the improvements observed with polybutylene terephthalate are not obtained when the polyester is poly(ethylene terephthalate).
A welcome contribution to the art would be a thermoplastic composition comprising PET that has improved HDT and good surface appearance. These highly desirable compositions are provided by this invention. | {
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Brazes and welds that connect brittle materials, such as carbide, to metal tools often affect the integrity of the brittle material. Consequently, many efforts have been made to improve the way in which brittle material forming high impact surfaces are attached. Examples of such efforts are disclosed in U.S. Pat. No. 4,944,559 to Sionnet et al., U.S. Pat. No. 5,837,071 to Andersson et al., U.S. Pat. No. 5,417,475 to Graham et al., U.S. Pat. No. 6,051,079 to Andersson et al., and U.S. Pat. No. 4,725,098 to Beach, all of which are herein incorporated by reference for all that they contain. | {
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This invention relates to overload protection or safety coupling devices for robotic tooling and of the general type disclosed in U.S. Pat. No. 4,954,005 which issued to the assignee of the present invention, and also as disclosed in U.S. Pat. No. 4,842,114 and No. 4,540,331. Such a safety or protection device is used between the end of an arm of a robot and the tooling carried by the arm and provides for opening an electrical control circuit to the shut down of the robot in the event the predetermined movement of the tooling by the robotic arm is accidentally blocked by an obstruction or by non-compliant movement of the robot arm due to a malfunction of the robot.
With any such safety or protection device, it is desirable for the device to operate and open the control circuit quickly in the event there is any rotational and/or tilting and/or axial movement of the tooling relative to the end of the robot arm. It is also desirable for the device to reset automatically with high return accuracy after the blockage is removed or the reason for the relative movement between the arm and the tooling is corrected. It has also been found desirable for the device to be compact with a low profile and have a high load capacity so that the robot arm may quickly move tooling having substantial size and weight or mass. While the safety or protection devices disclosed in the above patents provide some of the above desirable features, the devices have limitations which prevent the devices from providing all of the desirable features. | {
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Conventionally, well operation and production involves continuous monitoring of various subsurface formation parameters. Continuous monitoring of parameters such as, for example, reservoir pressure and permeability indicate the formation pressure change over a period of time. It is essential to predict the production capacity and lifetime of a subsurface formation. These parameters have generally been obtained during these operations either through wireline logging, drill stem tests or logging while drilling.
With the increase in the importance of production optimization in order to get more oil from depleted reservoirs, newly drilled wells, deep wells, wells having more complex trajectories and wells that are located in more challenging environments, long term monitoring of wells has become even more desirable. In order to achieve this, it is proposed to locate sensors in the formation, possibly buried some distance in the formation around the borehole outside the casing or tubing in the borehole, or in the formation prior to the installation of the casing or the tubing.
It is an object of the invention to provide a technique that allows sensors to be positioned outside the casing or very deep, such as 100, foot in the formation while still allowing communication without the problems of the previous techniques.
An example of one of these difficulties has been in communicating with the sensor through the casing or tubing and deep below the surface, and in providing electrical power to these sensors. The current invention has the advantage that the sensors are capable of communication through the casing or tubing and at high depths, and that they can be electrically powered. | {
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1. Field of the Invention
This invention relates generally to the field of fabrication of semiconductor devices and, more particularly, to a physical-vapor deposition (PVD) apparatus and method of using the apparatus.
2. Description of the Related Art
Sputtering, a type of physical vapor deposition, is widely used in semiconductor manufacturing to deposit thin metal or insulating films on semiconductor wafers.
Conventional sputtering apparatus 11 shown in FIG. 1 includes a process chamber 10 enclosing a target 12 affixed to the top thereof and a wafer pedestal 14 where a semiconductor wafer 16 rests during deposition. The target 12 is formed of a deposition material to be deposited. A lower shield 18 and an upper shield 20 are positioned within the chamber 10 such that they are electrically insulated from the chamber 10 and able to take on a floating electrical potential associated with the potential of the plasma of a gas, e.g. argon, generated within the chamber 10. Additionally, a cover ring 22 is engaged with the lower shield 18 to keep any deposition material from being deposited on the peripheral margin of the wafer 16.
During sputter deposition, the target 12 is bombarded by plasma ions within the chamber 10 by applying an appropriate voltage to the target 12, which causes particles of target material to be ejected from the target 12 toward the wafer 16. These particles deposit on the wafer 16 to form a desired film. During the deposition, however, particles of target can also deposit on the interior surfaces of the lower and upper shields 18 and 20. Also, a portion of the particles returns to the target 12 itself.
For these reasons, after a number of wafers are processed, the sputtering shields become coated with highly stressed, brittle barrier metal films, e.g., of TiN. Without proper treatment, these films can delaminate, flake off, and shower the substrate with particles.
Thus, it is necessary to coat the shields occasionally with metal such as titanium to prevent such particulation. This process is called xe2x80x9cpasting.xe2x80x9d A pasting material, such as titanium, is sputtered around the interior of the shields 18 and 20 along with the target 12. The layer of pasting material deposited onto the interior of the shields 18 and 20 forms a barrier to cracking and flaking between the layers of the high stress material. The pasting material such as titanium acts as a glue layer to secure the already-deposited films and to provide an adherent surface for any additional material particulate. The pasting material deposited on the target 12 must be cleaned before a normal sputtering process begins.
Conventionally, a standard shutter disk 24 and a shutter arm assembly 26 are used during pasting and cleaning of the target 12. Typically, the shutter disk 24 is housed in an enclosure 30 attached to the side of the process chamber 10. The shutter disk 24 is positioned between the pedestal 14 and the target 12 to isolate the target 12, and to protect other areas of the chamber 10 from subsequent cleaning of the target 12 and the pasting material. The shutter disk 24 is mounted on a rotating arm 32, i.e., an actuator arm, which is located outside the shield 18 and within the process chamber 10. When signaled to do so, the shutter arm assembly 26 rotates the disk 24 into the process chamber 10, overlying the wafer pedestal 14. The shutter disk 24 can then be raised into a pasting process position (at the same level as the wafer 16) by a wafer lift 34. Thus, cleaning of the target (sputtering away any contaminants present on the surface of target 12 onto the disk 24) or pasting without contaminating the surface of wafer pedestal 14 is possible because the wafer pedestal surface is protected by the shutter disk 24. When cleaning or pasting is completed, the shutter disk 24 returns to the storage position.
In semiconductor manufacturing, it is important to align a subsequent layer to a previous underlying layer. For this reason, alignment marks 37 (FIG. 2B) are typically formed on a wafer or on a reticle for alignment between various layers. The alignment marks are typically formed by etching a depth into a wafer. The alignment of one layer to the next is typically accomplished using a stepper. The stepper uses a laser beam to detect the position of the alignment marks on the wafer. It becomes difficult to maintain these alignment marks, especially in the back end of the manufacturing process, as the deposition over the marks makes the marks indistinguishable.
Recently, to protect the alignment marks from being damaged or contaminated by deposition, a two-tabbed alignment block-out scheme has been introduced. One of the process chambers incorporating the two-tabbed alignment block-out scheme is Endura Model (model number ENDURA(copyright) HP PVD(trademark)), available commercially from Applied Materials, Inc.
As illustrated in FIG. 2A, a cover ring 22xe2x80x2 has two tabs 35 protruding therefrom so that it can cover or protect alignment marks 37 of FIG. 2B on a semiconductor wafer 16xe2x80x2 during regular deposition steps. Alignment marks 37 positioned beneath the tabs 35 can be protected. As a result, the alignment marks 37 can be better maintained during deposition, and of course better alignment is possible with well-maintained alignment marks 37.
As shown in FIG. 2C, which is a cross-sectional view of a conventional cover ring taken in line 2Cxe2x80x942C of FIG. 2A, pins 38 are formed in the bottom of the cover ring 22xe2x80x2 in accordance with the two-tabbed alignment block-out scheme.
As illustrated in FIG. 2D, the cover ring 22xe2x80x2 is engaged with the lower shield 18. The pins 38 extending down from the bottom of the cover ring 22xe2x80x2 are engaged in the holes 42 in a cup 19 formed under the lower shield 18. This keeps the cover ring 22xe2x80x2 from rotating so that the cover ring 22xe2x80x2 with tabs 35 can be precisely fixed in place with respect to alignment marks 37 formed on a wafer 16.
However, conventional tabbed alignment block-out hardware with the cover ring 22xe2x80x2 and the lower shield 18 cannot use a standard shutter disk and shutter arm assembly because the pins 38 of the cover ring 22xe2x80x2 would interfere with the shutter disk 24 as indicated at 27 of FIG. 1. Particularly, if an actuator arm 25 were to attempt to put the shutter disk 24 onto the wafer pedestal 14, the shutter blade 32 would run into the pins 38 extending down from the lower shield 18.
Thus, there would be a clearance problem underneath the lower shield 18 if the shutter disk 24 were used with the two-tabbed block-out scheme.
Further, because the shutter disk 24 has to be sufficiently thick (to withstand various processing conditions), it can be inadvertently adhered to the tabs 35 by deposition during the pasting or the cleaning steps as illustrated in FIG. 3. Therefore, production wafers instead have been used for pasting by transferring the production wafers into the chamber and pasting on the wafers to avoid the clearance and gluing problems.
Unfortunately, using expensive production wafers each time to paste the chamber (which is required before each production lot) is costly and time consuming. Particularly, this is true because operator intervention is necessary to place an extra wafer in each production lot, leading to otherwise unnecessary exposure to mis-processing and it takes a long time to transfer the wafer to the chamber to be pasted. Also, because pasting is required quite often for the PVD chamber, a large number of production wafers can be wasted. Alternatively to using a wafer for pasting, an additional chamber having a metal disk for shuttering can be attached to the main chamber body and a robot arm can be used to pick up the disk and to transfer it to the chamber for pasting or cleaning of the target.
However, these prior art methods for cleaning targets or pasting deposition chambers significantly reduce throughput because they require significant non-productive down-time to transfer paste wafers from another location into the chamber for pasting. Also, in addition to the down time to transfer the metal disk to the pasting or the cleaning position, the metal disk for shuttering can stress the robot arm joints, thereby wearing out the robot arm assembly.
Accordingly, a need remains for a new sputtering apparatus that allows the use of a shutter and shutter arm assembly that do not require long down time to transfer a wafer or a shutter disk into the pasting or cleaning position, thereby improving the throughput without problems noted above.
The present invention provides a new sputtering apparatus that allow the use of a shutter disk and shutter arm assembly for pasting in a two-tab blockout scheme, thereby improving productivity and reducing waste of production wafers.
According to the present invention, physical vapor deposition (PVD) system comprises
a chamber, an upper shield and a lower shield mounted within the chamber, a cover ring having one or more tabs extending radially inwardly therefrom. The PVD system further includes a shutter disk having one or more notched areas formed in the periphery thereof to receive the one or more tabs of the cover ring. The cover ring has two or more recesses formed in an upper side thereof with a guide pin extending from the center of the recesses. The lower shield has two or more cups with a hole therein to be engaged with the guide pin of the cover ring to keep the lower shield from rotating with respect to the cover ring. The cups of the lower shield are inserted into the recesses of the cover ring. A wafer pedestal is mounted within the chamber. Additionally, the PVD system includes means for rotating the shutter disk to place the shutter disk on the wafer pedestal; and means for vertically adjusting the height of wafer pedestal.
With the shutter disk having notched areas and the modified cover ring, the present invention allows use of the shutter disk and shutter arm assembly without a clearance problem underneath the lower shield and without a gluing problem in a tabbed alignment block-out scheme. Thus, the present invention can be fully automated and significantly improve productivity.
The foregoing and other objects, features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment of the invention that proceeds with reference to the accompanying drawings. | {
"pile_set_name": "USPTO Backgrounds"
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There are three types of semiconductor lasers using semiconductor alloys as the laser cavity and these are distinguished by their laser effect generating modes. They are in fact injection laser diodes, electronic pumping lasers and optical pumping lasers. | {
"pile_set_name": "USPTO Backgrounds"
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There are a number of desirable characteristics of a denture fixative composition. One extremely desirable attribute is that it develops a high degree of tack upon contact with saliva in order that the dentures be held in place as soon as they are seated in the mouth. It is also highly desirable that the mucilage is spread over the denture-mucosa interface in order to effectively seal the denture in place and that the mucilages possess sufficient cohesive strength to withstand the stresses of mastication which act to rupture the seal and thus dislodge the denture. The denture fixative must also exhibit sufficient resistance to degradation under the extreme environmental temperature changes which occur in the oral cavity during such common actions as drinking coffee or other hot beverages.
Eberhard et al., in U.S. Pat. No. 2,997,399, teaches a dental fixative composition which is based on the use of hydroxyethyl cellulose and which also preferably contains methyl cellulose and polyacrylamide. The patent teaches that the hydroxyethyl cellulose should have an average degree of substitution of between 0.4 and 4.5 ethylene oxide groups per anhydroglucose unit. The patent further states that substantially equivalent results might be possible to obtain if only a minor proportion of the ethylene oxide groups are replaced with propylene oxide groups. However, the ethylene oxide cannot be replaced by propylene oxide at least as regards all or a substantial major portion of the ethylene oxide.
It has now been discovered that hydroxypropyl cellulose can be used in a denture fixative composition when combined with certain partially neutralized, optionally crosslinked polyacrylic acids or partially neutralized alkyl vinyl ether--maleic acid or anhydride copolymers, optionally crosslinked, or polyethylene oxide.
Numerous pharmaceutical formulations have employed polyacrylic acid and the use thereof has, in the past, been primarily directed to the exploitation of its thickening, suspending and emulsifying capabilities when the polymer is partially or wholly neutralized in amide or hydroxy solvents with an inorganic base, water soluble amine or some other combination thereof. In aqueous systems, the partially or wholly neutralized polyacrylic acid generates a gel which has low cohesive strength with a structure that may be easily ruptured when it is subjected to stresses such as those that occur during mastication.
U.S. Pat. No. 3,003,988 describes a dental fixative composition in which the dental fixative is a mixed partial salt containing calcium cations and alkali or quaternary ammonium cations of a lower alkyl vinyl ether-maleic anhydride type copolymer. The mixed salt copolymer is stated to be a water-insoluble but water-sensitized copolymer.
U.S. Pat. No. 3,736,274 teaches a dental fixative composition which contains a lower alkyl vinyl ether-maleic anhydride polymeric material, a polymeric N-vinyl lactam and a sodium carboxymethyl cellulose. The carboxymethyl cellulose prevents the maleic anhydride copolymer--N-vinyl lactam complex from completely precipitating when placed in water.
U.S. Pat. No. 3,868,432 teaches an anhydrous denture adhesive composition which is a mixture of a cationic polymeric component which is a copolymer of an acrylamide and an anionic synthetic gum component which can be a copolymer of maleic acid with vinyl lower alkyl ether.
The use of polyethylene oxide as a denture adhesive is described in U.S. Pat. No. 2,978,812.
It is the object of this invention to provide new and improved denture fixative compositions which exhibit sufficient cohesive strength to resist stresses such as those that occur upon mastication, which retain their fixative properties for prolonged periods of time and which exhibit resistance to the extreme environmental temperature changes encountered in use.
This and other objects of the invention will become apparent to those skilled in the art from the following detailed description. | {
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The present invention relates to a golf ball marker and especially to a golf ball marker having an arcuate edge for positioning around a golf ball.
In playing the game of golf, the golfer is allowed to lift the golf ball from the surface of a putting green for cleaning of the ball and to keep it from being a distraction or obstruction to other golfers. A lifted ball must, however, be marked to assure that when it is replaced it will be returned to the same spot from which it was lifted. Not only do the rules of golf permit such ball removal, it is the common practice and courtesy for a golfer to remove and mark a ball and replace it when it becomes his turn to putt. A ball marker must, however, be placed immediately behind the ball except if the mark is placed so that it would interfere with the play, stance, or stroke of another golfer, it should then be placed one or more putter lengths to one side. As a result of this common practice, many golfers carry a ball marker in their pocket and some simply employ a coin, such as a dime, for this purpose. A great variety of specialized ball markers have also been suggested and used. The most common ball marker being used is a disk about the size of a dime with a peg or prong extending axially from of the planar surfaces of the disk shaped body. In using a ball marker of the usual type, a golfer laterally moves the marker to a position approximate and at least partially under the ball to insure that he does not violate the provisions of the rules relating to placing the marker immediately behind the ball. When in this position, a golfer then presses down on the ball marker to cause the peg to penetrate the surface of the putting green and thereby positively locate the marker. This same basic marker locating technique is employed when a coin is used and even though the coin does not have an axial peg, most golfers will press the coin down into the grass to make sure it is lying flat and that it won't be moved by the grass or present an obstruction should another golfer's ball pass over the marker when it is being putted.
Prior art U.S. patents which show golf ball markers can be seen in the Cotchonis patent, U.S. Pat. No. 4,521,018, which is for a golf ball position marker for a golf ball that is to be lifted from the surface of the putting green and has a thin planar body defining an opening of at least semi-circular configuration and size so that the marker can be dropped vertically over the golf ball onto the surface of the putting green. The Fialon patent, U.S. Pat. No. 3,041,071, is a golf ball position marker in which a circular ring has a pointed prong extending from the center and bottom of the ring which can be pushed into the earth for marking the ball position. The Sakuma patent, U.S. Pat. No. 3,938,805, shows a golf accessory in which a circular golf ball marker is disk-shaped and includes VELCRO fastening material for retaining the marker.
The present invention is for a ball marker which can be conveniently carried on a key chain by a golfer and which includes a marker that can be placed partially around the golf ball by sliding it up to the golf ball rather than over the golf ball and can be easily viewed by parallel markers to the golf ball contact edge and includes means for marking and remarking with a pointed edge formed directly opposite to the concave ball engaging edge. The ball marker of this type can advantageously be inexpensively made and can be used in connection with corporation or golf club logos and advertising material and can have marking and remarking guidelines formed on the surface. | {
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A semiconductor chip consists of an array of devices whose contacts are interconnected by patterns of wiring metal strips. In VLSI chips, these metal patterns are multilayered and separated by layers of an insulating material. Interconnections between different metal wiring patterns are made by holes (or via holes), which are etched through the layers of insulating material. Typical chip designs consist of one or two wiring levels, with three wiring levels being the current state of the art. Circuit cost and performance continue to place demand on the fabrication processes in such a way that adding supplementary wiring levels can be competitive even though additional processing steps are required. However, the technique using via-holes, although widely used today, has multiple limitations and drawbacks in that, as the number of metallization layers increases wiring becomes increasingly difficult.
One particular drawback is that the structure produced leads to a very irregular surface, far from planar. Since it is necessary that the structure be planar, the surface is made planar by a variety of planarizing techniques.
It is well known to use ceramic substrates, particularly multilayer ceramic (MLC) substrates, as supports for mounting semiconductor devices thereon.
MLC technology for producing substrates for integrated circuit semiconductor package assemblies is well known in the art. The resultant substrate is capable of mounting many devices which are interconnected by the internal circuitry. External contact is made by a plurality of input/output (I/0) pins on the bottom side. The substrate is provided on the top surface with many small pads which are suitable for making solder connections to corresponding device terminals. Such MLC substrates require a relatively complex metallurgy on the topside to make connections to the integrated circuit devices and provide engineering change pads, and on the bottom to make connection to the I/O pads or other type connections. The complex metallurgy is comprised of several layers of metal which are selectively deposited in a predetermined pattern by additive and/or subtractive photolithographic processes.
Prior to the deposition of the top and bottom surface metallurgy, it may be desirable to planarize the surface of the substrate. The planarization may be accomplished by a variety of planarization techniques.
Instead of placing the top and bottom surface metallurgy directly on the surface of the ceramic substrate, the metallurgy may be placed on an intervening thin film layer (or a plurality of thin film layers) such as that disclosed in Boss et al. U.S. patent application Ser. No. 167,290, filed Mar. 11, 1988, the disclosure of which is incorporated by reference herein.
Again, prior to the deposition of the top and bottom surface metallurgy, it may be desirable to planarize the thin film layer. The planarization may be accomplished by a variety of planarization techniques.
Of the planarization techniques available today, a preferred one for electronic component substrates is chemical-mechanical (hereinafter chem-mech) polishing such as that disclosed in Chow et al. U.S. Pat. No. 4,702,792 and Beyer et al. U.S. patent application Ser. No. 791,860, filed Oct. 28, 1985, the disclosures of which are incorporated by reference herein. Also of interest is Rea U.S. Pat. No. 4,475,981, the disclosure of which is also incorporated by reference herein. Chem-mech polishing essentially enhances the removal of surface material by mechanically abrading the surface while applying an etchant that chemically attacks the surface. In order for chem-mech polishing to work, there must be at least two materials having differing etch rates such that the etchant affects one material more than the other. The effectiveness of the chem-mech polishing method ultimately depends on the precise etchant chosen.
For one reason or another, the chem-mech polishing slurries of the prior art have failed to produce a substrate surface that is acceptably planar.
Accordingly, it is an object of the present invention to have an improved chem-mech polishing method and slurry.
It is another object of the present invention to have an improved chem-mech polishing method and slurry that is available for use on a plurality of different material combinations.
These and other objects of the invention will become more apparent after referring to the following description considered in conjunction with the accompanying drawing. | {
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Industrial fluid is commonly stored in cylinders and tanks and is supplied to fluid distribution systems used in various industries through connections to the cylinders. Fluid distribution systems include devices to regulate or distribute gas, and pipe or tubing connecting the devices in the distribution system. The fluid cylinders typically have, or are connected to, a valve connectable to the distribution system for transfer of fluid from the cylinder to the fluid distribution system.
The valve fitting(s) used to connect the cylinder to the distribution system is often susceptible to particulate contamination as contaminants may find their way into the fitting. Thus, when a connection is made between the fluid distribution system and the fitting, particles in the fitting likely enter into the distribution system as a connection is made. This may jeopardize the integrity of the fluid being distributed and may have devastating consequences in the industry.
Plugs, known in the art, are used to plug up or cap the fitting before a connection is made to the fluid distribution system such that at least some particles are prevented from collecting in the fittings. Therefore, it is less likely that contamination of the fluid will occur upon connection of the tank with the fluid distribution system. However, the size of a fitting connected to each cylinder may vary. Therefore, multiple sizes of plugs are required to properly plug up or cap the different sized fittings. Further, fittings include threads for connection to the fluid distribution systems. In some fittings the threads are located on an outside surface, while in other fittings the threads are located on an inside surface of the fitting.
Therefore, it is an object of the present invention to provide a protection mechanism that will protect several different sizes and types of fittings.
In many situations, the fluids stored within the cylinder are utilized in medical and food and beverage applications. Contamination of fluids used in these situations may have negative health and safety implications. Therefore, it is important to be able to determine whether a party had access to the valve fitting connected to the tank and was thus presented with an opportunity to dispense fluid from the cylinder or, to perhaps even tamper with the fluid within the cylinder or the valve. Further, it is important to be able to determine or to be notified of whether an opportunity for particulate contamination of the fitting arose.
Therefore, it is an object of the present invention to provide a notification device. | {
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A known conventional information processing structure is described in Japanese Patent Laid-Open No. 2001-313386. The conventional information processing structure has quantum dots formed directly above the gate electrode of a metal oxide semiconductor field effect transistor (MOSFET), first and second information electrodes formed on the both sides of the quantum dots in an in-plane direction of the substrate in which the MOSFET is formed and a power supply electrode formed above the quantum dots.
The quantum dots are coupled to the gate electrode of the MOSFET and the power supply electrode by tunnel junction. In addition, each quantum dot is capacitively coupled to a corresponding one of the first information electrodes and a corresponding one of the second information electrodes.
In the conventional information processing structure, according to the potential of the first and second information electrodes, electrons migrate between the power supply electrode and the gate electrode via the quantum dots because of coulomb blockade. As a result, the potential of the capacitor formed between the information processing structure and the substrate varies.
Therefore, the conventional information processing structure compares the voltages applied to the first and second information electrodes by detecting the potential of the capacitor that varies with the potential of the two information electrodes. | {
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The statements in this section merely provide background information related to the present disclosure and may not constitute prior art.
Borescopes and video scopes used for inspecting visually obscure locations, hereinafter referred to as remote inspection devices, are typically tailored for particular applications. For instance, some remote inspection devices have been tailored for use by plumbers to inspect pipes and drains. Likewise, other types of remote inspection devices have been tailored for use by mechanics to inspect interior compartments of machinery being repaired.
Analog remote inspection devices are known which have hand-held control units using a power source such as a plurality of batteries, with data leads and power lines extending through a flexible cable to a light diffusing/image receiving head. Such devices commonly provide a remote light source to illuminate the area of interest and an imaging device to capture the illuminated image. Images provided by analog signal devices are adequate for many applications, however, where fine image detail is desired digital signal devices can convey greater volumes of data to improve the resolution. To further improve resolution, an increased power light source can also be used, created for example by increasing a quantity of light emitting components. However, increasing the quantity of light emitting components can introduce focal distortion and/or areas where light is not evenly diffused to illuminate a desired object. | {
"pile_set_name": "USPTO Backgrounds"
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Hydrocarbon gas separation by means of cryogenics has been employed in the gas processing industry for many years, the components of feed gas being readily susceptible to separation through pressure and temperature changes. A demethanizing column is customarily employed wherein the feed gas is heated and the vapors drawn off from the top of the column, and the liquid from the bottom. The column contains either beds consisting of metallic packing or equilibrium trays to aid in the separation process. It is desirable to draw off as much as of the vapors as possible prior to introduction of the liquid into the column. It is an object of this invention to accomplish a maximum separation of the raw feed gas components with a minimum utility consumption. | {
"pile_set_name": "USPTO Backgrounds"
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An image reading apparatus that is generally incorporated in a facsimile machine, a scanner, or the like is well known as a linear image reading apparatus, in which a transparent plate such as a glass plate is fixed by an adhesive over a row of photoelectric elements (refer to Japanese Patent Laid Open No. Sho. 63-9358 (1988), for instance).
FIG. 10 shows schematically the optical arrangement of a conventional linear image reading apparatus with the same basic configuration as above; FIG. 10 (a) is a schematic vertical section illustrating the boundary case of a ray of light originating from scattering at the surface of the photoelectric elements, and FIG. 10 (b) is a schematic plan view illustrating the extent of the portion of photoelectric elements 20 subjected to secondary incidence of light rays totally reflected at an upper boundary separating a protective plate and the outside air.
The conventional image reading apparatus shown in FIG. 10 includes a plurality of photoelectric elements 20 aligned in the transverse direction in the figure, and a glass plate 21 fixed by an adhesive layer 22 over the photoreceptive face of photoelectric elements 20 (the upper side in the figure). The glass plate 21 protects photoelectric elements 20 from both humidity and scanned originals so as not to be worn nor damaged by them, which consequently allows the image reading apparatus to maintain its resolution.
To describe an optical path in the image reading apparatus with the above configuration, an incident ray of light normal to glass plate 21 is taken for the sake of simplicity as an example. The incident ray of light normal to glass plate 21 (the ray indicated by a solid line in FIG. 10 (a)) goes straight through glass plate 21 and adhesive layer 22 of epoxy, for example, to impinge on the photoreceptive face 20a of photoelectric elements 20, where most of the ray is absorbed in photoelectric elements 20 and the remainder (indicated by a double-dotted line in the FIG. 10 (a)) is subject to diffuse back-scattering.
Here, for the purpose of sample calculations for tracing an optical path taken by the ray originating from scattering at the photoreceptive face 20a as described above, the thickness, d1, of adhesive layer 22 is taken as 15 .mu.m, the refractive indexes, n1 and n2, of adhesive layer 22 and glass plate 21 respectively as both 1.5, and the refractive index, n3, of air as 1. There is no reflection at boundary 9 separating adhesive layer 22 and glass plate 21, and the scattered ray continues in a straight line. The angle of incidence at which the ray in adhesive layer 22 strikes boundary 9 is therefore equal to the angle at which the ray is transmitted into glass plate 21, both of which are indicated by .theta..sub.1 in FIG. 10 (a). The scattered ray making the angle .theta..sub.1 to the normal goes straight in glass plate 21 to approach boundary 10 separating glass plate 21 and the outside air at the same angle. If this angle of incidence at boundary 10 is equal to or more than the critical angle, .theta. .sub.2, the ray is totally reflected at boundary 10 to return toward the photoelectric elements 20. The figure shows the boundary case of a ray of light scattered at the critical angle, .theta..sub.2, and returning to the photoreceptive face 20a at a point R2. This point R2 therefore delineates the inner boundary of the area exposed to secondarily incident rays. This boundary is indicated by a circle C shown in FIG. 10 (b), which is drawn using a point R1 as a center with a radius of Ld.sub.1, and the outside of circle C (the outside indicated by hatching in the figure) may receive light rays sent by total reflection. Here, R1 is assumed to be the point where the ray is first incident on photoreceptive face 20a and also where the scattered ray originated. To summarize, scattered rays of light originating at point R1 undergo total reflection at boundary 10 to return to positions outside circle C drawn round center R1 with radius Ld.sub.1.
Making the assumptions about the refractive indexes given above, the equation for calculating the critical angle, .theta..sub.2, for boundary 10 from which total reflection takes place, is expressed by:
1/sin.theta..sub.2 =n2/n3 (1)
where n2 is the refractive index of glass plate 21 and n3 is the refractive index of air.
Using the values given above, solving equation (1) for .theta..sub.2 gives .theta..sub.2 -41.8.degree. for the critical angle.
The isosceles triangle R1R2R3 shown in FIG. 10 (a) has as one side part of the transverse line representing the photoelectric elements 20 and as the other two, part of the double-dotted line representing the optical path taken by the boundary case of a scattered ray. From this triangle, elementary geometry yields the equation for calculating the distance Ld.sub.1 : EQU Ld.sub.1 =2(d1+d2)tan.theta..sub.2 ( 2)
where d1 is the thickness of adhesive layer and d2 is the thicknesses of glass plate 21.
Substitution of the values given above into equation (2) gives Ld.sub.1 =116.2 .mu.m for the distance.
As can be seen in FIG. 10 (b), two lines parallel with each other extend transversely, distance L1 apart, to form a strip-shaped area where photoelectric elements 20 are aligned end to end in the transverse direction (i.e. the fast scan direction). Accordingly, the distance L1 corresponds to the dimension of a side of a photoelectric element 20 in the slow scan direction orthogonal to the alignment direction. As shown in the figure, the strip-shaped area of width L1 extends into the hatched area, which means that some light rays subject to total reflection at boundary 10 are included there. The amount of scattered light falling within the strip-shaped area of width L1 can be represented as a proportion to the total light scattered at the critical angle or more. For the purpose of sample calculations of the amount of light, L1=63.5 .mu.m and Ld.sub.1 =116.2 .mu.m are assumed. The value of 63.5 .mu.m is equivalent to the dimension of a side of a photoelectric element 20 corresponding to a picture element density of 400 dots per inch. The strip-shaped area of width L1 intersects the circumference of circle C to form two circular arcs 23 and 24, each of which subtends a central angle .phi.1. Since L1=2.times.Ld1.times.sin(.phi.1/2), substitution gives .phi.1.times.31.7.degree. for the central angle. As mentioned above, the amount of light included in the area of width L1 can be represented as the proportion A of the total light scattered at the critical angle or more. The proportion A is roughly approximate to the ratio of twice the center angles .phi.1 to all directions, so that A=2.phi.1/360=0.18.
Thus, eighteen percent of the totally reflected rays at boundary 10 separating glass plate 21 and outside air, are incident again on photoelectric elements 20, to interfere with direct incident rays from the outside onto photoelectric elements 20, consequently resulting in lower resolving power of the image reading apparatus and image quality of the output image. | {
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1. Technical Field
The present invention relates to a power amplifier, and more particularly, to a power amplifier capable of restraining power and a method for restraining the power of the power amplifier.
2. Description of Related Art
Conventional power amplifiers may be classified into Class D power amplifiers and Class AB power amplifiers, among which the Class D power amplifiers are configured to output pulse modulated signals and the Class AB power amplifiers are configured to output linear signals. Owing to the advantage of high efficiency thereof, the Class D power amplifiers have now become a byword for power amplifiers.
Referring to FIG. 1, there is shown a circuit diagram of a conventional Class D power amplifier in which a dual-terminal output configuration is formed by a positive output terminal and a negative output terminal. This Class D power amplifier is advantageous in that by using the dual-terminal output configuration to drive a speaker 307, the driving power can be increased so that the speaker 307 can play the audio sound more efficiently.
Operation of this Class D power amplifier in the dual-terminal output configuration will now be described with reference to a single terminal as follows. From the terminal Vin, audio signals are inputted into an operational amplifier 301 and, by means of an integrator composed of the operational amplifier 301, a resistor R16 and a capacitor Cinl, the audio signals are transformed into self-oscillating triangular wave signals. Furthermore, square wave signals Vsquarel are inputted into the operational amplifier 301 via the terminal Rinl to synchronize the frequency of the triangular wave signals. Then, pulse-modulated signals are outputted through a comparator 302 to a pre-drive 305 which, according to the pulse-modulated signals, controls the on/off status of a power CMOS circuit 306 disposed at the output terminal, thereby to output signals for driving the speaker 307.
What described above is the circuit construction and operation of the conventional Class D power amplifier. The conventional Class D power amplifier is advantageous in that, the square wave signals are used as an input to control a carrier frequency of the output signals, and design of a square wave circuit is much simpler than that of a triangular wave circuit that is conventionally used. This saves room for circuits in the IC design and consequently reduces cost of the circuit layout. However, although the dual-terminal output configuration of the Class D power amplifier in which both the positive output terminal and the negative output terminal output signals can provide increased power for driving a load (e.g., the speaker), there is a risk that the load might be damaged due to an excessively large output power if a device for restraining power amplification is not provided.
Accordingly, in view of the shortcomings of the conventional Class D power amplifiers, the inventor of the present invention has made great efforts to make improvement thereon and finally provides an improved power amplifier and a method for restraining power of the improved power amplifier. | {
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The present invention relates to electro-optic displays and to components, especially backplanes, for use in such displays. The present invention is especially, though not exclusively, intended for use in such displays based on stainless steel or similar metal foil substrates.
In the displays of the present invention, the electro-optic medium will typically be a solid (such displays may hereinafter for convenience be referred to as “solid electro-optic displays”), in the sense that the electro-optic medium has solid external surfaces, although the medium may, and often does, have internal liquid- or gas-filled spaces, and to methods for assembling displays using such an electro-optic medium. Thus, the term “solid electro-optic displays” includes encapsulated electrophoretic displays, encapsulated liquid crystal displays, and other types of displays discussed below. Certain aspects of the present invention are primarily, although not exclusively, intended for use with encapsulated electrophoretic displays.
The term “electro-optic”, as applied to a material or a display, is used herein in its conventional meaning in the imaging art to refer to a material having first and second display states differing in at least one optical property, the material being changed from its first to its second display state by application of an electric field to the material. Although the optical property is typically color perceptible to the human eye, it may be another optical property, such as optical transmission, reflectance, luminescence or, in the case of displays intended for machine reading, pseudo-color in the sense of a change in reflectance of electromagnetic wavelengths outside the visible range.
The term “gray state” is used herein in its conventional meaning in the imaging art to refer to a state intermediate two extreme optical states of a pixel, and does not necessarily imply a black-white transition between these two extreme states. For example, several of the patents and published applications referred to below describe electrophoretic displays in which the extreme states are white and deep blue, so that an intermediate “gray state” would actually be pale blue. Indeed, as already mentioned the transition between the two extreme states may not be a color change at all.
The terms “bistable” and “bistability” are used herein in their conventional meaning in the art to refer to displays comprising display elements having first and second display states differing in at least one optical property, and such that after any given element has been driven, by means of an addressing pulse of finite duration, to assume either its first or second display state, after the addressing pulse has terminated, that state will persist for at least several times, for example at least four times, the minimum duration of the addressing pulse required to change the state of the display element. It is shown in published U.S. Patent Application No. 2002/0180687 that some particle-based electrophoretic displays capable of gray scale are stable not only in their extreme black and white states but also in their intermediate gray states, and the same is true of some other types of electro-optic displays. This type of display is properly called “multi-stable” rather than bistable, although for convenience the term “bistable” may be used herein to cover both bistable and multi-stable displays.
Several types of electro-optic displays are known. One type of electro-optic display is a rotating bichromal member type as described, for example, in U.S. Pat. Nos. 5,808,783; 5,777,782; 5,760,761; 6,054,071; 6,055,091; 6,097,531; 6,128,124; 6,137,467; and 6,147,791 (although this type of display is often referred to as a “rotating bichromal ball” display, the term “rotating bichromal member” is preferred as more accurate since in some of the patents mentioned above the rotating members are not spherical). Such a display uses a large number of small bodies (typically spherical or cylindrical) which have two or more sections with differing optical characteristics, and an internal dipole. These bodies are suspended within liquid-filled vacuoles within a matrix, the vacuoles being filled with liquid so that the bodies are free to rotate. The appearance of the display is changed to applying an electric field thereto, thus rotating the bodies to various positions and varying which of the sections of the bodies is seen through a viewing surface. This type of electro-optic medium is typically bistable.
Another type of electro-optic display uses an electrochromic medium, for example an electrochromic medium in the form of a nanochromic film comprising an electrode formed at least in part from a semi-conducting metal oxide and a plurality of dye molecules capable of reversible color change attached to the electrode; see, for example O'Regan, B., et al., Nature 1991, 353, 737; and Wood, D., Information Display, 18(3), 24 (March 2002). See also Bach, U., et al., Adv. Mater., 2002, 14(11), 845. Nanochromic films of this type are also described, for example, in U.S. Pat. No. 6,301,038, International Application Publication No. WO 01/27690, and in U.S. Patent Application 2003/0214695. This type of medium is also typically bistable.
Another type of electro-optic display, which has been the subject of intense research and development for a number of years, is the particle-based electrophoretic display, in which a plurality of charged particles move through a suspending fluid under the influence of an electric field. Electrophoretic displays can have attributes of good brightness and contrast, wide viewing angles, state bistability, and low power consumption when compared with liquid crystal displays. Nevertheless, problems with the long-term image quality of these displays have prevented their widespread usage. For example, particles that make up electrophoretic displays tend to settle, resulting in inadequate service-life for these displays.
Numerous patents and applications assigned to or in the names of the Massachusetts Institute of Technology (MIT) and E Ink Corporation have recently been published describing encapsulated electrophoretic media. Such encapsulated media comprise numerous small capsules, each of which itself comprises an internal phase containing electrophoretically-mobile particles suspended in a liquid suspending medium, and a capsule wall surrounding the internal phase. Typically, the capsules are themselves held within a polymeric binder to form a coherent layer positioned between two electrodes. Encapsulated media of this type are described, for example, in U.S. Pat. Nos. 5,930,026; 5,961,804; 6,017,584; 6,067,185; 6,118,426; 6,120,588; 6,120,839; 6,124,851; 6,130,773; 6,130,774; 6,172,798; 6,177,921; 6,232,950; 6,249,271; 6,252,564; 6,262,706; 6,262,833; 6,300,932; 6,312,304; 6,312,971; 6,323,989; 6,327,072; 6,376,828; 6,377,387; 6,392,785; 6,392,786; 6,413,790; 6,422,687; 6,445,374; 6,445,489; 6,459,418; 6,473,072; 6,480,182; 6,498,114; 6,504,524; 6,506,438; 6,512,354; 6,515,649; 6,518,949; 6,521,489; 6,531,997; 6,535,197; 6,538,801; 6,545,291; 6,580,545; 6,639,578; 6,652,075; 6,657,772; 6,664,944; 6,680,725; 6,683,333; 6,704,133; 6,710,540; 6,721,083; 6,727,881; 6,738,050; 6,750,473; and 6,753,999; and U.S. Patent Applications Publication Nos. 2002/0019081; 2002/0021270; 2002/0060321; 2002/0063661; 2002/0090980; 2002/0113770; 2002/0130832; 2002/0131147; 2002/0171910; 2002/0180687; 2002/0180688; 2002/0185378; 2003/0011560; 2003/0020844; 2003/0025855; 2003/0038755; 2003/0053189; 2003/0102858; 2003/0132908; 2003/0137521; 2003/0137717; 2003/0151702; 2003/0214695; 2003/0214697; 2003/0222315; 2004/0008398; 2004/0012839; 2004/0014265; 2004/0027327; 2004/0075634; 2004/0094422; 2004/0105036; 2004/0112750; and 2004/0119681; and International Applications Publication Nos. WO 99/67678; WO 00/05704; WO 00/38000; WO 00/38001; WO 00/36560; WO 00/67110; WO 00/67327; WO 01/07961; WO 01/08241; WO 03/107,315; WO 2004/023195; and WO 2004/049045.
Many of the aforementioned patents and applications recognize that the walls surrounding the discrete microcapsules in an encapsulated electrophoretic medium could be replaced by a continuous phase, thus producing a so-called polymer-dispersed electrophoretic display, in which the electrophoretic medium comprises a plurality of discrete droplets of an electrophoretic fluid and a continuous phase of a polymeric material, and that the discrete droplets of electrophoretic fluid within such a polymer-dispersed electrophoretic display may be regarded as capsules or microcapsules even though no discrete capsule membrane is associated with each individual droplet; see for example, the aforementioned 2002/0131147. Accordingly, for purposes of the present application, such polymer-dispersed electrophoretic media are regarded as sub-species of encapsulated electrophoretic media.
A related type of electrophoretic display is a so-called “microcell electrophoretic display”. In a microcell electrophoretic display, the charged particles and the suspending fluid are not encapsulated within microcapsules but instead are retained within a plurality of cavities formed within a carrier medium, typically a polymeric film. See, for example, International Application Publication No. WO 02/01281, and published US Application No. 2002/0075556, both assigned to Sipix Imaging, Inc.
Although electrophoretic media are often opaque (since, for example, in many electrophoretic media, the particles substantially block transmission of visible light through the display) and operate in a reflective mode, many electrophoretic displays can be made to operate in a so-called “shutter mode” in which one display state is substantially opaque and one is light-transmissive. See, for example, the aforementioned U.S. Pat. Nos. 6,130,774 and 6,172,798, and U.S. Pat. Nos. 5,872,552; 6,144,361; 6,271,823; 6,225,971; and 6,184,856. Dielectrophoretic displays, which are similar to electrophoretic displays but rely upon variations in electric field strength, can operate in a similar mode; see U.S. Pat. No. 4,418,346. Other types of electro-optic displays may also be capable of operating in shutter mode.
An encapsulated or microcell electrophoretic display typically does not suffer from the clustering and settling failure mode of traditional electrophoretic devices and provides further advantages, such as the ability to print or coat the display on a wide variety of flexible and rigid substrates. (Use of the word “printing” is intended to include all forms of printing and coating, including, but without limitation: pre-metered coatings such as patch die coating, slot or extrusion coating, slide or cascade coating, curtain coating; roll coating such as knife over roll coating, forward and reverse roll coating; gravure coating; dip coating; spray coating; meniscus coating; spin coating; brush coating; air knife coating; silk screen printing processes; electrostatic printing processes; thermal printing processes; ink jet printing processes; and other similar techniques.) Thus, the resulting display can be flexible. Further, because the display medium can be printed (using a variety of methods), the display itself can be made inexpensively.
Whether a display is reflective or transmissive, and whether or not the electro-optic medium used is bistable, to obtain a high-resolution display, individual pixels of a display must be addressable without interference from adjacent pixels. One way to achieve this objective is to provide an array of non-linear elements, such as transistors or diodes, with at least one non-linear element is associated with each pixel, to produce an “active matrix” display. An addressing or pixel electrode, which addresses one pixel, is connected to an appropriate voltage source through the associated non-linear element. Typically, when the non-linear element is a transistor, the pixel electrode is connected to the drain of the transistor, and this arrangement will be assumed in the following description, although it is essentially arbitrary and the pixel electrode could be connected to the source of the transistor. Conventionally, in high resolution arrays, the pixels are arranged in a two-dimensional array of rows and columns, such that any specific pixel is uniquely defined by the intersection of one specified row and one specified column. The sources of all the transistors in each column are connected to a single column electrode, while the gates of all the transistors in each row are connected to a single row electrode; again the assignment of sources to rows and gates to columns is conventional but essentially arbitrary, and could be reversed if desired. The row electrodes are connected to a row driver, which essentially ensures that at any given moment only one row is selected, i.e., that there is applied to the selected row electrode a voltage such as to ensure that all the transistors in the selected row are conductive, while there is applied to all other rows a voltage such as to ensure that all the transistors in these non-selected rows remain non-conductive. The column electrodes are connected to column drivers, which place upon the various column electrodes voltages selected to drive the pixels in the selected row to their desired optical states. (The aforementioned voltages are relative to a common front electrode which is conventionally provided on the opposed side of the electro-optic medium from the non-linear array and extends across the whole display.) After a pre-selected interval known as the “line address time” the selected row is deselected, the next row is selected, and the voltages on the column drivers are changed to that the next line of the display is written. This process is repeated so that the entire display is written in a row-by-row manner. Thus, in a display with N rows, any given pixel can only be addressed for a fraction 1/N of the time.
Processes for manufacturing active matrix displays are well established. Thin-film transistors, for example, can be fabricated using various deposition and photolithography techniques. A transistor includes a gate electrode, an insulating dielectric layer, a semiconductor layer and source and drain electrodes. Application of a voltage to the gate electrode provides an electric field across the dielectric layer, which dramatically increases the source-to-drain conductivity of the semiconductor layer. This change permits electrical conduction between the source and the drain electrodes. Typically, the gate electrode, the source electrode, and the drain electrode are patterned. In general, the semiconductor layer is also patterned in order to minimize stray conduction (i.e., cross-talk) between neighboring circuit elements.
Liquid crystal displays commonly employ amorphous silicon (“a-Si”) thin-film transistors (“TFT's”) as switching devices for display pixels. Such TFT's typically have a bottom-gate configuration. Within one pixel, a thin-film capacitor typically holds a charge transferred by the switching TFT. Electrophoretic displays can use similar TFT's with capacitors, although the function of the capacitors differs somewhat from those in liquid crystal displays; see application Ser. No. 09/565,413, filed May 5, 2000 (now U.S. Pat. No. 7,030,412), U.S. Patent Publication No 2002/0106847 and the aforementioned 2002/0060321. Thin-film transistors can be fabricated to provide high performance. Fabrication processes, however, can result in significant cost.
In TFT addressing arrays, pixel electrodes are charged via the TFT's during a line address time. During the line address time, a TFT is switched to a conducting state by changing an applied gate voltage. For example, for an n-type TFT, a gate voltage is switched to a “high” state to switch the TFT into a conducting state.
Many electro-optic materials require application of a drive voltage for a significant switching time (typically of the order of 10−2 to 10−1 seconds) to effect a transition between their two extreme optical states. For high resolution displays containing at least (say) 100 rows and columns, if a reasonable scan rate is to be maintained, the period for which an individual pixel is addressed during a single scan is much less than the switching time of the electro-optic medium, and accordingly much of the switching of a pixel is effected by the voltage which remains on the pixel electrode between successive times of addressing the pixel (i.e., while other columns of the display are being addressed). This remaining voltage gradually decays due to current passing through the electro-optic material of the pixel and any current leakage through the non-linear element. The rate at which this decay occurs can be reduced (and the average voltage applied to the pixel during one complete scan of the display thus increased—this is commonly referred to as “increasing the voltage holding capacity” of the pixel) by connecting the pixel electrode to a capacitor.
At least some of the aforementioned electro-optic media can be made sufficiently flexible to permit their use in flexible displays based upon flexible substrates such as metal or polymeric films. Some recent publications of previous related work applied to electrophoretic displays on steel foil substrates and related technologies include: Y. Chen, P. Kazlas, K. Denis and P. Drzaic, in SID Intl. Symp. Digest Tech. Papers, San Jose 2001 (Society of Information Display, San Jose) p. 157; P. Kazlas, A. Ritenour, J. Au, Y. Chen, J. Goodman, R. Paolini and H. Gates, in 22nd Intl. Display Research Conference Nice 2002 (Society of Information Display, San Jose); Au, Y. Chen, A. Ritenour, P. Kazlas and H. Gates, 9th Intl. Display Workshops Hiroshima 2002 (Society of Information Display, San Jose); Suo et al., Mechanics of rollable and foldable film-on-foil electronics, App. Phys. Lett., 74, 1177 (22 Feb. 1999).
However, manufacturing flexible microelectronic backplanes for such displays presents many challenges. A key problem in the manufacture and operation of such thin film transistors on flexible substrates is thin film cracking Typically, the a-Si films used can withstand between 1-2% strain before cracking.
In one aspect, the present invention relates to backplane and display structures designed to minimize the cracking problems in electro-optic displays. In other aspects, the present invention relates to various improvements in backplanes for electro-optic displays, components for use in such backplanes and processes for the manufacture of such backplanes, which improvements may be useful in overcoming the aforementioned problems. | {
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In thermally assisted optical/magnetic data storage, information bits are recorded on a layer of a storage medium at elevated temperatures, and the heated area in the storage medium determines the data bit dimension. Heat assisted magnetic recording (HAMR) generally refers to the concept of locally heating a recording medium to reduce the coercivity of the recording medium so that the applied magnetic writing field can more easily direct the magnetization of the recording medium during the temporary magnetic softening of the recording medium caused by the heat source. For heat assisted magnetic recording (HAMR) a tightly confined, high power laser light spot is used to preheat a portion of the recording medium to substantially reduce the coercivity of the heated portion. Then the heated portion is subjected to a magnetic field that sets the direction of magnetization of the heated portion. In this manner the coercivity of the medium at ambient temperature can be much higher than the coercivity during recording, thereby enabling stability of the recorded bits at much higher storage densities and with much smaller bit cells. Heat assisted magnetic recording can be applied to any type of magnetic storage media, including tilted media, longitudinal media, perpendicular media and patterned media.
In HAMR disc drives, it is desirable to efficiently deliver the laser light to the recording head. One approach would be to place a laser source directly on the slider. However, that approach requires additional electrical connections to the slider for the laser. Also, the electrical power dissipated by the laser will substantially heat the slider, which is undesirable for obtaining the best performance from the reader. The added mass of the laser on the slider (or suspension assembly) may also degrade the dynamic and shock performance of the suspension.
Alternatively, a laser source can be located elsewhere in the disc drive and its emitted light carried to the slider through an optical fiber. This approach eliminates the problems with the laser on the slider mentioned above, but introduces a new problem, which is how the optical connection is made between the fiber and the slider. Optical fiber is typically very stiff. If the fiber is physically attached to the slider, the stiffness complicates the design of the gimbal structure which allows the slider to fly over the surface of the disc. Therefore, it is desirable to have a small free space gap between the end of the fiber and the slider. The fiber should be brought to the slider along the suspension and then positioned so that the emitted light illuminates the optical transducer on the slider. One way that has been proposed to do this is to include a mirror or prism on the suspension to direct the laser beam toward the slider.
There is a need for a recording device that can provide localized heating of a recording medium without the need for mirrors, multiple optical components or sharp bends in an optical fiber. | {
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A. Overview of An Exemplary Acousto-Optic Filter
Wavelength division multiplexing technology (e.g., Wavelength Division Multiplexing (WDM), Dense Wavelength Division Multiplexing (DWDM), etc.) involves the launching of a plurality of communication signals over a single optical fiber, wherein, each communication signal has its own associated optical wavelength. As such, the signal processing associated with wavelength division multiplexing technology involves the ability to process a particular communication signal at its own associated optical wavelength (or optical wavelength range).
An acousto-optic filter is a type of filter that can be “tuned” so as to filter the optical passband of an optical fiber at a specific optical wavelength. Thus, for example, an acousto-optic filter can be used to filter a single WDM/DWDM communication signal from a group of WDM/DWDM communication signals that exist on the same optical fiber. That is, the passage of optical energy being carried by the optical fiber at a specific optical wavelength (or a specific optical wavelength range) is attenuated. As a result, the strength of one or more communication signals that fall within the range of the filtered optical wavelength(s) is reduced. Reducing the strength of a communication signal can be useful if the signal is part of an overall equalization scheme.
An acousto-optic filter includes an excitation element that launches an acoustic wave along an optical fiber. The acoustic wave affects the optical properties of the optical fiber so that the optical signal strength(s) that reside at specific optical wavelength(s) is (are) attenuated. FIG. 1a shows an example of an acousto-optic filter. A continuous optical fiber is shown in FIG. 1a as having at least three sections 104a, 104b and 104c. A first section 104a of the optical fiber effectively acts as the input node to the filter; and, a third section 104c of the optical fiber effectively acts as the output node from the filter. A second section 104b of the optical fiber (which may also be referred to as the “acousto-optic interaction” section), as seen in FIG. 1a, is the section of the fiber that propagates an acoustic wave.
A transducing ring 101 that is made of piezo-electric material (e.g., PbZrT (PZT), PbMnN, etc.) and a horn 102 (which is often made of Aluminum (Al) or glass or other metals or ceramics) can be integrated together to form an excitation element that launches the acoustic wave onto the second optical fiber section 104b. A damper 103 absorbs acoustic wave energy so that the fiber section 104c that acts as the filter output may be kept physically rigid.
As a result of the activity of the excitation element, as seen in FIG. 1a, an acoustic wave is formed on the acousto-optic interaction fiber section 104b that propagates in the +z direction. The acoustic wave has a wavelength λf and an amplitude B. The wavelength λf and the amplitude B of the acoustic wave are a function of the properties of the transducing ring 101, the properties of the horn 102 and the amplitude and frequency of an electronic signal that is provided to the transducing ring 101 by an electronic signal source 105 (e.g., a voltage signal source) as briefly described immediately below.
In the exemplary embodiment of FIG. 1a, the electronic signal that is provided by the electronic signal source 105 has been expressed as Acos(2πfst). By positioning the leads that carry the electronic signal across the thickness “T” of the transducing ring 101, the electronic signal will induce a time-varying electric field across the transducing ring 101 (e.g., along the z axis as drawn in FIG. 1a). The transducing ring 101, being made of piezo-electric material, will “vibrate” in response. The direction of the vibrational response depends upon the “polling direction” of the transducing ring.
A polling direction is a property of piezo-electric material that indicates along which direction a piezo-electric stress can be induced. For example, if transducing ring 101 of FIG. 1a has its polling direction set along the y axis, the transducing ring 101 will vibrate along the y axis. That is, the dimension of the transducing ring 101 along the y axis will change with time. For example, in response to an oscillating electric field of frequency fs along the z axis, the transducing ring's height dimension “H”, as drawn in FIG. 1a, will oscillate (also at a frequency of fs) between some minimum height and some maximum height.
The amplitude of the transducing ring's stress is a function of the amplitude of the applied electric field; which, in turn, is a function of the amplitude “A” of the electronic signal Acos(2πfst). As such, according to the exemplary embodiment of FIG. 1a, the electronic signal determines both the frequency and the amplitude of the stress experienced by the transducing ring 101. The transducing ring 101 described just above can be referred to as a “shear mode” transducing ring because its polling direction is perpendicular to the direction of the applied electric field. Other transducing ring embodiments may have alternate polling directions (such as a thickness mode transducing ring having a thickness that varies with time).
The horn 102, as a result of its conical shape, amplifies the transducing ring's vibration and propagates it onto the acousto-optic interaction optical fiber section 104b. As an example of this amplification, the tip of the cone 120 can be made to vibrate with an amplitude of 100.0 nm and a frequency of fs if the cone 102 has an acoustic gain of 103 and the transducing ring 101 and electronic signal combine to produce a 0.1 nm transducing ring 101 stress that oscillates at a frequency of fs.
This vibration is then transferred to the acousto-optic interaction fiber section 104b at the tip of the cone 120 (which causes the fiber to propagate an acoustic wave of approximately the same amplitude and frequency in the +z direction). The wavelength λf of the acoustic wave is a function of its velocity “v” and its frequency fs (i.e, λf=v/fs, where the velocity “v” is a function of the material composition of the optical fiber and its surrounding medium (such as a vacuum)). As discussed above, the amplitude of the acoustic wave B is a function of the amplitude A of the electronic signal. FIG. 1b shows an exemplary optical transfer function 106 for the acousto-optic filter that results from the acousto-optic wave observed in FIG. 1a.
According to the transfer function 106 of FIG. 1b, the wavelength λf of the acoustic wave of FIG. 1a determines which optical frequency λO is filtered; and, the amplitude B of the acoustic wave of FIG. 1a determines the extent 107 to which the optical frequency λo is attenuated. Better said, according to the transfer function 106 of FIG. 1b, optical frequencies other than λo are more easily passed through the acousto-optic interaction portion of the optical fiber 104b with a relatively high transmission of T1.
However, optical frequencies at or near λo (as represented by point 107 in FIG. 1b) are passed along the acousto-optic interaction section 104b of the optical fiber with a relatively low transmission of T2 (which corresponds to high attenuation). By varying the frequency fs of the electronic signal provided to the transducing ring 101, the attenuation frequency λo can be made to vary; and, by varying the amplitude of the electronic signal A, the extent of the optical attenuation can be made to vary. Thus, by controlling the frequency fs and amplitude A of the electrical signal, the optical transfer function 106 of an acousto-optic filter can be “tuned” so as to prescribe a particular attenuation for a particular optical wavelength.
B. Reflections in Acousto-Optic Filters
A problem with acousto-optic filters is the presence of acoustic reflections that propagate along the acousto-optic interaction portion 104b of the optical fiber. As is known in the art, a change in the transportation medium of a wave induces a reflection of that wave. Thus, when an acoustic wave traveling in the +z direction along the acousto-optic interaction portion 104b of the fiber impinges upon the damper 103, a reflected wave is induced along the acousto-optic interaction portion 104b that travels in the −z direction. A portion of this reflected wave may then be reflected in the +z direction at the tip 120 of the cone 102.
Those of ordinary skill will recognize that the above described phenomena will cause “interaction” between the originally launched and reflected waves suitable for the establishment of a “standing wave” or “beating” on the second optical fiber portion 104b. Beating of the second harmonic type corresponds to amplitude fluctuation over time. An exemplary depiction of an acoustic-optic wave as it experiences beating of the second harmonic type is shown in FIG. 2a. Note that the acoustic wave is drawn as having: 1) a first amplitude at a first moment in time t1 (with solid line 204b1); and 2) a second amplitude at a second moment in time t2 (with dashed line 204b2). Consistent with the dynamics of acousto-optic filtering as discussed in the preceding section, a variation in acoustic wave amplitude, which also corresponds to time varying acousto-optic wave energy, will result in time varying attenuation through the filter for signals having wavelength λO.
The variation in attenuation, which may also be referred to as optical intensity modulation, is observed in the transfer function 206 of FIG. 2b by a pair of profiles: 1) a first (solid) profile 207 having greater attenuation (e.g., as associated with solid acoustic wave 204b1 of FIG. 2a); and 2) a second (dashed) profile 209 having lesser attenuation (e.g., as associated with dashed acoustic wave 204b2 of FIG. 2b). This fluctuation in attenuation corresponds to inconsistent filtering and thus can lead to inconsistent signal processing of wavelength division multiplexed signals. | {
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Security apparatus for preventing a dead bolt lock apparatus being unlocked from the outside of a door.
In my U.S. Pat. No. 4,951,982, there is disclosed a security member removably positionable between an interior portion of a lock housing and a dead bolt handle to prevent movement of the dead bolt from its locked position by one exterior of the room using a proper key. The security member includes a device having a first end portion with a pair of legs that are extendable under the lock handle cross bar and are tapered to be of a height that progressively increases in a direction toward the second end portion, the second end portion having a generally planar door facing surface coextensive with the first end portion planar door facing surface. An adjustment member is mounted by the second end portion and has a foot abutable against the lock to vary the angle of the device door facing surface relative to the lock.
In U.S. Pat. No. 4,279,137 to Cook there is disclosed security mechanism that includes a plate having a downwardly opening notch to have the dead bolt lock handle extended therethrough. Struts are mounted by the plate to prevent the lock handle being turned by one using a key outside of the door when the door handle extends through the notch. Dominguez, U.S. Pat. No. 3,585,827, functions in a manner somewhat similar to that disclosed by Cook.
In U.S. Pat. No. 3,263,464 to Suroff et al there is disclosed a locking device that includes a lock having a generally rectangular lock block located inside a room and a lock actuator within the room that is turned when using a key outside of the room. A somewhat U-shaped base has a lower leg to abut against the block lower edge, a second leg adapted to abut against the upper edge of the block, a pair of adjustment screws mounted by the second leg and adapted to be turned for adjusting the spacing of the second leg from the block, and a recess for receiving the lock actuator therein to prevent the lock actuator rotating when it is attempted to unlock the door from outside of the room. One of the limitations of this type apparatus is that if the lock does not have a rectangular block extending into the room, the apparatus can not be used in a manner suggested by this patent.
Anderson 689,152 discloses a plate having a curved portion that is inclined at an angle to limit the degree of opening of a door. A screw is threaded into the plate and has its lower end mounting a foot to abut against the floor. By turning the screw the angle of the plate relative to the floor can be increased above that provided by the curve portion.
Albright, U.S. Pat. No. 1,338,205, discloses a door check having downwardly extending teeth to engage the floor vertically opposite and a substantial distance longitudinally remote from where the door engages the door check, while Bellamy, 776,378, discloses a door check having serrations along the longitudinal length of the vertical plates thereof and an adjustment device for vertically elevating the plate end portion opposite where the plates engage the door.
In order to provide a simpler, more inexpensive devices for door locks than that disclosed in the above mentioned prior art, this invention has been made. | {
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The present invention relates to portable power tools in general, especially to so-called impact type power tools wherein a reciprocable tool is struck by an impeller, and more particularly to improvements in portable power tools wherein the tool (such as a rock drill or chisel) receives motion from a fluid-operated motor. Still more particularly, the invention relates to improvements in portable power tools wherein a rotary and/or reciprocable tool receives motion from a hydraulic motor.
It is already known to provide a portable impact hammer with an impeller which is reciprocable by pressurized hydraulic fluid so that it performs alternating forward and return strokes and strikes against a tool during each of its forward strokes. The fluid is pressurized in a discrete aggregate having a pump which is driven by an electric motor or by a combustion engine and whose outlet is connected with the power tool by a flexible conduit. Another flexible conduit connects the housing of the power tool with a reservoir for hydraulic fluid.
A drawback of the just described power tools is that they are costly, complex, bulky and require frequent maintenance. Also, their efficiency is relatively low, especially due to leakage of hydraulic fluid which must be conveyed through several elongated flexible conduits, and also due to elasticity of such conduits. Moreover, the power tools as well as the aforementioned aggregates are noisy and the maximum distance between the power tool proper and the aggregate which supplies pressurized hydraulic fluid is relatively short. Still further, the versatility of conventional hydraulically operated portable power tools is rather limited. | {
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1. FIELD OF THE INVENTION
The invention relates to a key container or keyholder which may be combined with a wallet and more specifically, the invention is directed to an improved device for carrying and protecting keys in conjunction with credit and business cards, photos, identification, keys and the like.
The invention further relates to an improved device to securely retain keys and which provides for a more compact or slender storage with added protection from loss as compared with keychains, keytainers and other prior key retention devices. More particularly, the invention is directed to providing for combined storage of a multiple number of keys plus storage and protection of credit cards, photos, and identification cards.
The invention can be used in a variety of situations including storage in back pockets, coat pockets and purses, either as a separate key storage unit or as indicated in combination with men and women billfolds and wallets. When used separately, the invention provides an apparatus that allows keys to lay flat as possible in a man's pants or jacket pocket. This is a substantial improvement over existing practices wherein keys would make a lump or bulge in one's pocket.
The utility and unique advantages of this invention stem from the method of construction and the arrangement of the elements of this invention and is more fully described herein.
2. DESCRIPTION OF PRIOR ART
Various prior art combination keyholders and wallets are well known and found to be exemplary of the U.S. prior art. They are:
U.S. Pat. No.:
1,719,120 PA1 1,877,910 PA1 1,877,911 PA1 1,877,912 PA1 2,219,561 PA1 2,635,665 PA1 2,703,596 PA1 2,704,101 PA1 3,926,234 PA1 4,286,641 PA1 4,331,194 PA1 4,417,612 PA1 Miles PA1 L'Enfant PA1 L'Enfant PA1 L'Enfant PA1 Miller PA1 Ashley PA1 Kromer PA1 Wittrien PA1 Dean PA1 Watson PA1 Lederer PA1 Couture
Inventor:
U.S. Pat. No. 1,719,120 to Miles discloses a wallet for keys, but does not disclose an outside edge or enfoldment to prevent keys from slipping out.
U.S. Pat. Nos. 1,877,910, 1,877,911, and 1,877,912 to L'Enfant disclose combined cardcase and keyholders. However neither of these devices discloses a means for systematically retaining different shaped and sized keys neatly and uniformly in the holding sections of said devices. Each discloses a flap or fold to protect the keys from loss, thus making removal of the keys very difficult. The present invention does not require a flap or fold.
U.S. Pat. No. 2,219,561 to Miller discloses a key case in which keys may be secured and specifically discloses a flap of V-shape for the securement of the key, biasing one or two keys toward a kerf or enclosure within the material of the billfold.
U.S. Pat. Nos. 2,635,665 to Ashley and 4,417,612 to Couture, et al, disclose pocket keyholders. The Ashley patent secures keys via a series of zig-zag stitching which does not fully utilize the space within the device nor does it secure keys from loss by utilizing an outside rib as does the present invention. In the case of Couture, et al., two outer sheets of material fully encompass the extent of a plurality of keys thus precluding ready identification thereof while disparate material, in the form of Velcro strips are used to close the access to the contained keys.
U.S. Pat. No. 2,703,596 to Kromer discloses a device with two flaps to keep keys in place. In a similar manner U.S. Pat. No. 3,926,234 to Dean discloses a device with panels and flaps and individualized compartments in which keys are stored, these compartments having no means of biasing keys against the material thereby to secure them for greater safety.
U.S. Pat. No. 4,286,641 to Watson discloses a combination business card and key storage device utilizing transparent sheets with slits for the insertion of keys and subsequently requiring the user to fully open the device for the removal of keys.
U.S. Pat. No. 4,331,194 to Lederer shows a key holding device utilizing two pockets formed by folds of material over a baseboard. Keys thus stored are not individually contained and are thereby subject to falling out of the folds.
Likewise, the Kromer U.S. Pat. No. 2,703,596 and U.S. Pat. No. 2,704,101 to Wittrien do not provide the same method of securing keys as does the present invention. These inventions relate to methods of securing keys based on the use of flaps, enclosures or compartments.
These patents or known prior uses teach and disclose various types of combined wallets and keyholders. None of them, however, taken singly or in combination, disclose the combination of the present invention in such a way as to bear upon the claims of this invention. | {
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Thermally insulated metal containers, commonly known as thermos or vacuum bottles, are constructed of an inner and an outer metal casings to create a double-walled space therebetween and evacuating the space to create a thermal insulation barrier. A method for making such thermos bottles has been disclosed in a Japanese patent, JPN 60-36766 (Kokoku). According to this patented method, a thermos bottle shown in FIG. 28 consists of an inner casing 1 and an outer casing 2 having a bottom, to create a space 3 therebetween to be evacuated for thermal insulation. A thermos bottle can be made from such a structure by joining a reduced diameter section 4a, of the body section 4 of the outer casing 2, to the mouth section 1a of the inner casing 1. To the bottom opening 5 (shown at the top in FIG. 28) is attached a bottom section 6 to complete the construction of a container assembly of the thermos bottle. There is a stepped section 6a in the center area of the bottom section 6, and there is an evacuation opening 7 in the central region of the stepped section 6a. This opening 7 is brazed shut with a sealing plate 8 after evacuation of the space 3 to seal in the vacuum.
This vacuum sealing operation is performed by inverting the bottle as shown in FIG. 28, placing pieces of brazing material around the stepped section 6a, supporting the sealing plate 8 to provide a space between it and the stepped section 6a, evacuating followed by heating so as to evacuate space 3 and melt the brazing material to allow the sealing plate 8 to drop under its own weight to braze shut the evacuation opening 7.
This method of joining was susceptible to sealing defects produced by the dislocation of brazing material and the sealing plate 8 prior to brazing due to rushing air streams at the evacuation opening 7 through the space (between it and the stepped section 6a) as well as by the uncontrolled flowing of the brazing material around the peripheries of the stepped section 6a during brazing.
In addition, it was difficult to automate the placement of the brazing material properly, necessitating a manual operation. Furthermore, the sealing plate was necessary only to provide sealing of the evacuation opening 7. These were two of the main reasons for increasing the cost of production of metal thermos bottles. | {
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1. Field of the Invention
This invention relates to a dry type isostatic pressing apparatus, and more particularly to the improvement thereof characterized by supplying forcibly gas between the outer peripheral surface of a molded body or a shaping thin rubber bag where the molded body is housed and the inner peripheral surface of the shaping rubber mold, and the gas having a pressure higher than the isostatic pressure applied to the shaping rubber mold at the time when the said shaping rubber mold begins to restore to its original state during the decompression step thereof, as well as to an apparatus therefor.
2. Description of the Prior Art
In this kind of isostatic pressing, powders to be molded which have been packed in a rubber mold are compressed and molded in the presence of a isostatic pressure imparted to the rubber mold, and the isostatic pressing has often been utilized in the formation of pottery articles, fire bricks, ceramic moldings, etc. However, starting molded bodies for forming these articles have, in general, low tensile strength and low modulus of elasticity, and so some defects have been inevitable in the molding step thereof such that molded bodies are broken or cracks in the form of round slices occur in the molded bodies, when the molded bodies are released from the rubber mold during the decompression step, particularly in case of shaping long and slender columns.
Our experiments have clarified the following facts: In the molding operation according to the isostatic pressing, in general, the rubber mold in the apparatus is gradually compressed, and after the isostatic pressure has reached a desired one, the pressure is kept as such for a predetermined period of time, and thereafter the step transfers to the decompression step, while a non-compressible fluid such as oil, water or the like is used as a pressure medium, and so when the step has transferred to the decompression step, the rubber mold is restored to the original state thereof by the aid of the elastic force of the rubber mold itself at almost the termination of the reduced pressure step, without any rapid restoration corresponding to the rapid reduced pressure effect. In the restoration of the rubber mold, the restoring timing in the direction of the axis of the mold is earlier than that in the perpendicular direction thereof, in other words, the restoration of the rubber mold in the axis direction thereof is effected in such a state that a pressure is imparted to the molded body in the perpendicular direction of the axis thereof, and thus, a friction occurs between the surface of the rubber mold and that of the shaped molding and the resulting friction power on the surface of the molded body acts on the said surface as a tension. On these grounds, the molded body is broken or cracks occur therein. In addition, it also has been clarified that the more the shaping rubber mold thickens, the more the said tension increases.
In order to eliminate the said drawbacks, for example, such a means has heretofore been taken that powders to be molded are put in a thin rubber bag so as to evade the direct contact between the powders and the rubber mold, an antifriction agent is coated on the outer surface of the rubber bag. However, said means inevitably causes some drawbacks such that the operation step is complicated and the rubber mold is tainted or damaged by the coating of the antifriction agent. | {
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It is known that transmission of a digital signal through a medium, whether wired or wireless, can result in the digital signal becoming distorted due to affects of the medium. Digital signals transmitted though a wireless medium (i.e., wireless signals) can be distorted due to effects of multipath fading, magnitude response, and phase response of the wireless medium. Digital signals transmitted though a wire medium (i.e., wired signals) can also be distorted due to effects of magnitude response and phase response of the wired medium. Distortion of a digital signal can lead to loss of data, or data that is not properly interpreted by a receiver of the digital signal.
A variety of methods of signal coding have been developed to address the above issues, particularly for wireless media. To be successful, however, most of these methods require prior knowledge of the medium fading and attenuation characteristics. In static situations, where the medium (i.e., channel) does not change with respect to time (e.g., a wired channel or a static wireless channel), a pre-characterization, in which characteristics of the channel are measured before a transmission of data, is sufficient to characterize the channel. Channel fading and attenuation effects can be measured in the pre-characterization, and corrections can be used to compensate at a receiving system.
However, in many practical applications, channel characteristics vary with respect to time. For example, a wireless transmitter or a wireless receiver can be moving, resulting in a changing communication channel. In these cases, some form of dynamic channel characterization is required to characterize the channel as it changes over time.
A common approach for performing the dynamic channel characterization is to incorporate one or more reference or calibration signals into a digital signal being transmitted in a communication. The calibration signals are often referred to as pilot tones, or pilot symbols. The format and content of the pilot tones are predetermined, and therefore, known at the receiver. When the pilot tones are detected at the receiver, any one of various algorithms can be used in order to derive a desired channel compensation by a comparison of characteristics of the known pilot tones to characteristics of the received pilot tones. For example, the amplitude and a phase of the pilot tones can be used for comparison.
A disadvantage of using pilot tones is that the pilot tones carry no data. Therefore, use of the pilot tones results in a loss of channel bandwidth that could otherwise be used for data transmission. The loss of bandwidth is exacerbated if the channel changes rapidly, wherein the pilot tones must be transmitted more often in order to dynamically update the channel characteristics used by the receiver for compensation.
To be of general utility in a practical environment, wireless communications, and in particular, wireless digital communications, must be robust in a variety of static and dynamic applications having multipath fading, attenuation, and other losses that degrade a transmitted digital signal as it propagates through a wireless medium to a receiver. The office environment typifies a somewhat static environment. In the office, the office occupants move about, but the principal sources of multipath reflections, such as furniture and walls, are generally fixed in place. Therefore, a wireless communication channel in an office environment can have relatively constant channel characteristics.
In contrast, mobile users, such as pedestrians and motorists in an urban setting, represent dynamic situations in which the characteristics (i.e., magnitude and phase response) of a communication channel change greatly and sometimes rapidly. In the case of the motorist using, for example, a cellular telephone, changes to characteristics of the wireless channel (or medium) occur very rapidly in the presence of movement, which can correspond to movement of several wavelengths in as little as 10 ms. The communication channel used by the motorist needs frequent characterizations using a multiplicity of pilot symbols. For the pedestrian using, for example, a cellular telephone, changes to characteristics of the wireless medium occur less rapidly and characterization of the channel are needed less often.
A ship, and especially a military ship, represents a unique and particularly challenging environment in which a wireless signal must propagate through a communication channel comprised of Faraday cages, i.e., all-metal compartments. Furthermore, reflective surfaces within the compartments are subject to movement. For example, airplanes and equipment in the hanger deck of an aircraft carrier are frequently moved over distances much greater than a wavelength of the wireless signal. Helmets, vehicles, and landing craft in the loading area, i.e., the well deck, of an amphibious landing ship, also move about the ship. Within the challenging shipboard environment, channel characteristics are subject to dynamic change at rapid rates.
Numerous coding approaches have been developed to maintain signal quality in the presence of multipath fading, attenuation, and other losses. However, most of these methods require prior knowledge of channel characteristics to optimally reconstruct and decode the received signal. This can be an issue in situations where channel characteristics are changing rapidly.
Space-time coding, known to those of ordinary skill in the art, is an example of one of the many forms of signal coding techniques used to achieve diversity gain (e.g., multiple channels) to operate in the presence of multipath fading, attenuation, and other problems. However, most forms of space-time coding require knowledge of channel characteristics.
Block coding, also known to those of ordinary skill in the art, is a computationally straightforward method using space-time coding. Block coding also requires knowledge of channel characteristics.
In order to obtain the knowledge of channel characteristics, a method of characterization of a communication channel is needed. For static cases, such as the typical office environment, measurement of characteristics (e.g., frequency response and phase response) of the channel prior to use may be sufficient. For dynamic cases, where channel characteristics change with respect to time, frequent measurement of the channel characteristics is necessary.
As described above, pilot tones embedded in a digital data stream can be used to provide the dynamic channel characterization, but at the expense of channel bandwidth. Some examples of conventional pilot tones include:
pilot tones described in IEEE 802.11; and
pilot tones transmitted at the same time as the data, but at a different frequency, for example, pilot tones transmitted in the sub-channels of OFDM (orthogonal frequency division multiplexing).
Methods for measuring communication channel characteristics from transmitted pilot tones generally fall into three categories: correlation, Best Linear Unbiased Estimator (BLUE), or Minimum Mean Square Error (MMSE). Computational complexity increases from correlation to BLUE to MMSE.
Correlation provides a direct comparison of a received pilot tone signal to an expected pilot tone signal, using correlation techniques. The expected pilot tone signal is a version of the pilot tone signal that would be expected to be received if it propagated through a perfect communication channel, i.e., a communication channel having no multipath, a flat magnitude response and a zero phase response. Correlation is the most computationally straightforward of the three methods, but it is also the most sensitive to noise.
The BLUE method convolves the expected pilot tone signal with an estimate of the channel response, compares that result with the received pilot signal, and computes the difference between the two. The BLUE method then identifies the channel response that minimizes the mean square error between the expected pilot tone signal and the received pilot tone signal. This approach is more computationally intensive than correlation, in that a matrix, which incorporates the pilot data, must be inverted.
The MMSE method has elements in common with correlation and BLUE. Like BLUE, MMSE minimizes the mean square error between an expected pilot tone signal and a received pilot tone signal, and it also involves a matrix inversion. In addition, the noise power must be known at the receiver. At each channel estimation, the matrix must be reconstructed with the present noise power, requiring an additional complication. At high signal-to-noise ratios, MMSE resembles BLUE, but at low signal-to-noise ratios, MMSE resembles correlation.
Some channel characterization methods do not require as many pilot tones, or none at all. These methods are known as semi-blind and blind techniques, respectively.
Semi-blind techniques take advantage of feedback from a receiver. Turbo channel estimation and subspace-based methods are among the semi-blind approaches. Turbo channel estimation begins with a training set of pilot symbols, and then improves the channel estimation in succeeding iterations. Subspace-based methods invoke temporal correlations between consecutive data sets. All of these methods are effective at reducing the number of pilot tones that must be processed to achieve reliable channel characteristic estimation.
Blind techniques can eliminate use of pilot tones altogether. These methods fall into two categories: those based on Second Order Cyclostationary Statistics (SOCS) and those based on Higher Order Statistics (HOS). The SOCS technique requires the system to be stationary for a limited time period, and HOS requires signals at the receiver to be statistically independent. Therefore, SOCS may not be applicable to systems that are changing rapidly, and in general, HOS will not be readily applicable to MIMO (Multiple Input/Multiple Output) channels that have been Space-Time coded, because the coded signals are not statistically independent.
It would, therefore, be desirable to have a channel characterization method and system that can characterize a communication channel during a communication with minimum loss of channel bandwidth, and which can be used to identify channel characteristics for a communication channel that has dynamically changing characteristics. | {
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The present invention relates to methods and devices for improving ventricular function of the heart and, more particularly, to an in-vivo method and device for improving diastolic function of the left ventricle of the heart.
Heart failure is commonly defined as the inability of the left ventricle, herein, also referred to as LV, to generate an adequate cardiac output at rest or during exertion, while operating at a normal or enhanced LV filling pressure. Congestive heart failure (CHF) is a clinical syndrome in which heart failure is accompanied by the symptoms and signs of pulmonary and/or peripheral congestion. Heart failure is most commonly associated with impaired LV systolic function. A widely used index for quantifying systolic function is ‘ejection fraction’ (EF), defined as the ratio of stroke volume to end-diastolic volume, which can be estimated using techniques such as radiocontrast, radionuclide angiography, and/or, echocardiography. The normal value of EF is 0.67±0.08, which is frequently depressed in systolic heart failure even when the stroke volume is normal. A value of EF≧0.50 is commonly used as an indicator of normal systolic function. It is notable, however, that as much as 30-50% of all patients with typical symptoms of congestive heart failure have a normal or slightly reduced ejection fraction, that is, a value of EF≧0.45.
In these patients, diastolic dysfunction is implicated as a major contributor of congestive heart failure. In some patients, systolic and diastolic heart failure coexist. The most common form of heart failure, the one caused by coronary arteriosclerosis, is an example of combined systolic and diastolic failure, as described in “Braunwald's Heart Disease: Review and Assessment”, third edition, 1997, Saunders Company Publishers. There are about 4.6 million people in the United States with heart failure, and about 550,000 are being reported annually, as indicated by Vasan, R. S., and Benjamin, E. J., in “Diastolic Heart Failure—No Time To Relax”, New England Journal of Medicine 2001, 344: 56-59. Also indicated therein, is that the mortality rate from diastolic heart failure (DHF), 5-12% annually, is about four times that among persons without heart failure and half that among patients with systolic heart failure, and that, nonetheless, rates of hospitalization and health care associated with diastolic heart failure rival those associated with systolic heart failure.
Primary diastolic dysfunction is typically observed in patients with hypertension and hypertrophic or restrictive cardiomyopathy, but can also occur in a variety of other clinical disorders and has a particularly high prevalence in the elderly population. Aging is associated with ‘physiologic’ diastolic dysfunction due to the increase in LV muscle mass and changes in passive elastic properties of the myocardium, hence, the concern of an increase in the incidence of diastolic dysfunction as the aging of the western world population progresses.
For the purpose of clearly understanding, and implementing, the following described preferred embodiments of the present invention, relevant details, description, and, definitions of selected terms, well known to one of ordinary skill in the art, of physiological and pathological aspects, mechanisms, and functions, of the heart, in general, and of the ventricles and atria, in particular, are provided herein. Additional details, description, and, definitions of terms, thereof, are readily available in the scientific literature.
The left ventricle is the chamber on the left side of the heart that receives oxygenated arterial blood from the left atrium and contracts to drive it into the aorta for distribution to the body. The right ventricle is the chamber on the right side of the heart that receives deoxygenated venous blood from the right atrium and drives it into the pulmonary artery in order to receive oxygen from the lungs. Diastole is the normal rhythmically occurring relaxation and dilatation (stretching, expansion, dilation) of the heart cavities (ventricles), during which the cavities are filled with blood. Atrial contraction occurs during the last stage of diastole of the ventricle and aids ventricular filling. Systole is the rhythmic contraction of the heart, especially of the ventricles, by which blood is driven through the aorta and pulmonary artery after each dilation or diastole.
Ventricular filling starts just after mitral valve opening. As the LV pressure decreases below that in the left atrium, the phase of rapid or early filling of the LV accounts for most of ventricular filling. LV filling temporarily stops as pressure in the atrium and left ventricle equalize, commonly known as the phase of diastasis, occurring prior to atrial contraction and during which little blood enters the filled left ventricle. Atrial contraction increases the pressure gradient from the atrium to the left ventricle to renew filling. When the LV fails to relax normally, as in ‘LV hypertrophy’, increased atrial contraction can enhance late filling. Relaxation (inactivation of contraction) is a dynamic process that begins at the termination of contraction and occurs during isovolumetric relaxation and early ventricular filling. ‘Myocardial elasticity’ is the change in muscle length for a given change in force. ‘Ventricular compliance’ is the change in ventricular volume for a given change in pressure, and, ‘ventricular stiffness’ is the inverse of compliance.
The ‘preload’ is the load present before contraction has started and is provided by the venous return that fills the ventricle during diastole. The ‘Frank Starling law of the heart’ states that the larger the volume of the heart, the greater the energy of its contraction and hence the stroke volume is larger. In other words, when the preload increases, the left ventricle distends (widens, expands) and the stroke volume increases, as described by Opie, H. L., in “The Heart Physiology, From Cell To Circulation”, third edition, Lippincott-Raven publishers, 1998. The pressure-volume relation curves are an accepted description of the ventricular function.
FIG. 1, adapted from the previously cited “Braunwald's Heart Disease: Review and Assessment” reference, is a schematic diagram illustrating a typical pressure-volume loop of a normal subject (dotted line) and a patient with diastolic dysfunction (solid line); wherein dashed lines, between the letters ‘a’ and ‘b’, and, ‘c’ and ‘d’, represent the diastolic pressure-volume relation of the normal subject, and, the patient with diastolic dysfunction, respectively. FIG. 1 shows that isolated diastolic dysfunction is characterized by a shift in the pressure-volume loop to the left. Contractile performance is normal, associated with an ejection fraction (EF) value≧0.45, with a normal or slightly decreased stroke volume. However, LV (left ventricular) pressures throughout diastole are increased, at a common diastolic volume equal to about 70 ml/m2. In the patient with diastolic failure, LV end diastolic pressure is about 25 mm Hg, compared with an LV end diastolic pressure of about 5 mm Hg in the normal subject. Thus, diastolic dysfunction increases the modulus of chamber stiffness. A main objective of treating the patient with diastolic dysfunction is to cause the diastolic pressure-volume relation curve (dashed line between ‘c’ and ‘d’) to go back to the diastolic pressure-volume relation curve (dashed line between ‘a’ and ‘b’, also indicated by the arrow), of the normal subject, by decreasing the end diastolic LV pressure for the same LV volume.
The fundamental problem in diastolic heart failure (DHF) is the inability of the left ventricle to accommodate blood volume during diastole at low filling pressures, as described by Mandinov, L., Eberli, F. R., Seiler, C., and Hess, M. O., in “Diastolic Heart Failure”, Cardiovacular Res. 2000, 45: 813-825. Initially, hemodynamic changes may be manifested only in an upward displacement of the diastolic pressure-volume curve in the presence of a normal end-diastolic volume with inappropriate elevation of LV diastolic, left atrial and pulmonocapillary pressure (as previously described above, with reference to FIG. 1). More severe resistance to LV filling may cause inadequate filling even in enhanced diastolic pressure with an additional leftward shift of the diastolic pressure-volume relation, resulting in a decreased end diastolic volume and depressed stroke volume, as described by Mandinov, L., et al.
Currently, four different pathophysiological mechanisms are known and used for understanding and/or explaining diastolic heart failure (DHF), combinations of which may readily take place in a particular patient: (1) slow isovolumic left ventricular relaxation, (2) slow early left ventricular filling, (3) reduced left ventricular diastolic distensibility, and, (4) increased left ventricular chamber stiffness or increased myocardial muscle stiffness, as described in the report, “How To Diagnose Diastolic Heart Failure: European Study Group On Diastolic Heart Failure”, European Heart Journal, 1998, 19: 990-1003.
Slow isovolumic left ventricular relaxation, (1), refers to a longer time interval between aortic valve closure and mitral valve opening and a lower negative peak ventricular dP/dt. Regional variation in the onset, rate, and extent of myocardial lengthening is referred to as ‘diastolic asynergy’, temporal dispersion of relaxation, with some fibers commencing to lengthen later than others, is referred to as ‘asynchrony’. Slow early left ventricular filling, (2), is a result of slow myocardial relaxation, segmental incoordination related to coronary artery disease and the atrioventricular pressure gradient. Reduced left ventricular diastolic distensibility, (3), refers to an upward shift of the LV pressure-volume relation on the pressure-volume plot, irrespective of a simultaneous change in slope. Reduction in LV end diastolic distensibility is usually caused by extrinsic compression of the ventricles as in cardiac tamponade. Increased LV chamber stiffness or increased myocardial muscle stiffness, (4), as manifested by a shift to a steeper ventricular pressure-volume curve, is due to processes such as ventricular hypertrophy, endomyocardial fibrosis, disorders with myocardial infiltration (for example, amyloidosis) and replacement of normal, distensible myocardium with non-distensible fibrous scar tissue in healed infarct zones.
The previously cited European Study Group proposed criteria for the diagnosis of DHF. Accordingly, simultaneous presence of the following three criteria is considered obligatory for establishing a diagnosis of DHF: (1) evidence of CHF, (2) normal or mildly abnormal LV systolic function, (3) evidence of abnormal LV relaxation, filling, diastolic distensibility, or, diastolic stiffness.
Pulmonary edema is the result of the increase in pulmocapillary pressure and is due to a shift of liquid from the intravascular compartment to the lung interstitial compartment.
Pulmonary edema is frequently associated with hypertension. Gandhi, S. K. et al. in “The Pathogenesis Of Acute Pulmonary Edema Associated With Hypertension”, New England Journal of Medicine, 2001, 344: 17-22, have contradicted the hypothesis that pulmonary edema, apparently associated with hypertension, in patients with preserved ejection fraction, is due to transient systolic dysfunction. They found that the LV ejection fraction and the extent of regional wall motion measured during the acute episode of hypertensive pulmonary edema were similar to those measured after the resolution of the congestion, when the blood pressure was controlled, thus concluding that the pulmonary edema was due to diastolic rather than systolic heart failure.
The management of diastolic heart failure is difficult. There have been no large-scale, randomized controlled trials of therapy in diastolic heart failure, and there remains substantial disagreement about the appropriate therapy for this disease, according to Sweitzer. N. K., and Stevenson, L. W., in “Diastolic heart Failure: Miles To Go Before We Sleep”, American Journal of Medicine, 2000, 109: 683-685. Medical therapy of diastolic dysfunction is often empirical and lacks clear-cut pathophysiologic concepts, as indicated in previously cited Mandinov, L. et al. No single drug presently exists which selectively enhances myocardial relaxation without negative effects on LV contractility or pump function, and thus, there is a significant need for a new therapeutic approach for this particular type of heart disease.
Treatment of diastolic heart failure may be logically divided into three areas or categories: (1) removal of the precipitating cause, (2) correction of the underlying cause, and, (3) control of the congestive heart failure state. Treatment goals that have been advocated, by previously cited Mandinov, L. et al., and, by Braunwald, E., in “Heart Failure”, Harrison's Principles of Internal Medicine, fourteenth edition, McGraw Hill publishers, are as follows:
1. Reduction of central blood volume. Reduction of salt intake and use of diuretics (usually, loop diuretics). Diuretics are effective in reducing pulmonary congestion, shifting the pressure-volume relation downwards. However, they must be used with care because the volume sensitivity of patients with diastolic dysfunction bears the risk that excessive diuresis may result in a sudden drop in stroke volume. Because of the steep pressure-volume relationship, a small decrease in diastolic volume will cause a large decrease of the filling pressure, and will result in a drop in stroke volume, and thus, in cardiac output.
2. Reduction of workload. Reduction of physical activity, maintenance of emotional rest and use of vasodilators. Vasodilators, such as sodium nitroprusside or ACE inhibitors reduce the filling pressure and the afterload in all patients, and elevate cardiac output. Reduction of an elevated left ventricular end diastolic pressure may improve subendocardial perfusion, thus improving myocardial contraction. Nonetheless, vasodilators have not been useful in the management of isolated diastolic heart failure and are more effective in combined heart failure, as indicated in the previously cited Braunwald, E. text. Vigorous control of hypertension is imperative in patients with heart failure caused by diastolic dysfunction, because control of hypertension may prevent progression or partially reverse the disorder by addressing the primary cause of most cases, as described by Grauner, K., in “Heart Failure, Diastolic Dysfunction And The Role Of The Family Physician”, American Family Physician, 2001, 63: 1483-1486.
3. Improvement of LV relaxation. In particular, by using calcium channel blockers or ACE inhibitors. Ca2+ channel blockers have been shown to improve myocardial relaxation and enhance diastolic filling. These drugs may be best matched to the pathophysiology of relaxation disturbances due to their ability to decrease cytoplasmic calcium concentration and reduce afterload. However, currently, use of Ca2+ channel blockers is limited due to their negative inotropic effects (negative influence on the systolic function of the heart), and clinical trials have not clearly proven them to be beneficial.
4. Regression of LV hypertrophy. In particular, decrease in wall thickness and removal of excess collagen by ACE inhibitors and AT-2 antagonists or Spironolactone. Philbin, E. F., Rocco, T. A., Lindenmuth, N. W., Ulrich, K., and Jenkins, O. L., in “Systolic Versus Diastolic Heart Failure In Community Practice: Clinical Features, Outcomes, And The Use Of ACE Inhibitors”, American Journal of Medicine, 2000, 109: 605-613, have shown that the use of ACE inhibitors in patients with ejection fraction equal to or greater than 0.50 was associated with a better NYHA class (New York Heart Association functional and therapeutic classification for stages of heart failure) after discharge from hospitalization, but had no significant effect on mortality or hospital readmission. ACE inhibitors and AT-2 antagonists effect blood pressure, reduce afterload, and effect the myocardium via the local renin-angiotensin system. These effects are important for regression of LV hypertrophy, and improvement of elastic properties of the myocardium.
5. Maintenance of atrial contraction and control of heart rate. In particular, by using beta-blockers and/or antiarrhythmics. Beta-blockers reduce blood pressure and myocardial hypertrophy. The positive effect on diastolic dysfunction is mainly due to slowing of the heart rate and not to a primary improvement in isovolumic relaxation or the diastolic properties of the left ventricle.
6. NO donors. NO (Nitric Oxide) donors have been shown to exert a relaxant effect on the myocardium, which is associated with a decrease in LV end diastolic pressure. In patients with severe LV hypertrophy, an increased susceptibility to NO donors has been documented, which may be beneficial for the prevention of diastolic dysfunction.
7. Heart transplantation. Heart transplantation is a definitive treatment for end stage heart failure.
8. Biventricular pacing. Biventricular pacing improves uncoordinated contraction due to left bundle branch block or other conduction abnormalities with wide ‘QRS complex’ (P-Q-R-S-T waveform) of an electrocardiogram, which are common in patients with CHF. Morris-Thurgood, J. A., Turner, M. S., Nightingale, A. K., Masani, N., Mumford, C., and, Frenneaux, M. P., in “Pacing In Heart Failure: Improved Ventricular Interaction In Diastole Rather Than Systolic Re-synchronization”, Europace 2000, 2: 271-275, have shown that left ventricular pacing acutely benefits congestive heart failure patients with pulmonary capillary wedge pressure greater than 15 mm Hg, irrespective of left bundle branch block. They suggested the beneficial mechanism might be related to an improvement of ventricular interaction in diastole (VID) rather than ventricular systolic re-synchronization. According to their suggestion, LV pacing in patients with high LV end diastolic pressure, will delay right ventricular filling and allow greater LV filling before the onset of VID. Biventricular pacing, however, has not been clinically proven effective in the treatment of patients with diastolic heart failure.
To one of ordinary skill in the art, there is thus a need for, and it would be highly advantageous to have an in-vivo method and device for improving diastolic function of the left ventricle of the heart, while minimally disturbing systolic function of the heart. Moreover, there is a need for such a method and device which is biocompatible and is specially configured for compact and long-term reliable use in humans. | {
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In European Patent Application No. 7930019.0 a laminar support is described and illustrated to provide a credit card or the like having as code and value elements zones or areolae formed by depositing thereon a thin film consisting of ferromagnetic materials or alloys with properties of uniaxial, magnetic anisotropy, i.e. having a rectangular hysteresis loop according to a certain axis parallel to the plane of the thin film and referred to as the easy axis, and a flat or almost null hysteresis loop according to an axis orthogonal to the first one and referred to as the hard axis. This is achieved in a particular environment, e.g. by means of a deposition of a ferromagnetic material or Fe-Ni alloys on a laminar support such as a credit card, an identity card or the like with techniques of electro-deposition or evaporation under hard vacuum and in the presence of a magnetic field tangential to the plane of the support.
The direction of this field will specify the above mentioned easy axis, and the magnetization moment will have only two steady states of orientation according to the two directions of said axis. The film may be deposited on a plurality of zones or areolae, each of them comprising one information unit or bit as a function of both the thickness, and consequently the intensity of the magnetic induction, and the direction of orientation of the easy magnetization axis. In particular, in the specific case of a credit card some areolae can be designed for containing the information relevant to the identification of said credit card, while other areolae are credit or value elements and are designed for progressive cancellation by means of destruction during the services for which the credit card has been provided.
The present invention seeks to provide a device for indentifying some selected characteristics of the material having uniaxial, magnetic anisotropy and deposited on the areolae or zones of a credit card or the like, and eventually for cancelling at least a portion of said areolae.
In this invention a thin film of the above mentioned Fe-Ni alloys having uniaxial, magnetic anisotropy exhibits physical properties such that, if it is subjected to a field produced by a conductor passing a current of frequency f.sub.o and lying on a plane parallel to that of the thin film and oriented according to the easy magnetization axis, it induces in a second conductor lying on the same plane and orthogonal to the first conductor a signal of frequency 2f.sub.o.
This invention utilizes this physical property to provide a non-volatile reading/writing memory, in which the information unit or bit is given by the direction of orientation of the magnetic moment vector of the areola concerned. In such an application the excitation and detection conductors forming the reading/writing device are lying on the same support as the thin film and are integral therewith, their distance from the plane of the thin film being only some microns.
The end result is that of determining only the direction of the magnetic moment vector regardless of an evaluation of the physical quantity concerned. | {
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The invention relates to releasing a silicone-based pressure-sensitive adhesive composition from contact with a release liner after aging.
Silicone-based pressure-sensitive adhesive compositions are very versatile because they tend to exhibit good adhesion to a variety of substrates including glass, ceramic, vinyl siding, finished wood, and painted drywall under challenging environmental conditions including temperature and humidity extremes. Many silicone-based pressure-sensitive adhesive compositions are coated onto a release liner as a wet composition, dried and wound up into a roll. Providing the silicone-based pressure-sensitive adhesive on a release liner facilitates further processing of the adhesive including, e.g., transfer laminating, converting and packaging.
Release liners provide a variety of functions for pressure-sensitive adhesive compositions including, e.g., preventing contamination of the adhesive layer, facilitating handling of the adhesive or an adhesive-coated article (e.g., by providing support thereto as well as covering the adhesive), identifying articles on which the release liner is disposed and combinations thereof. A release liner is often left in place on a pressure-sensitive adhesive composition until the adhesive layer is converted, packaged, or shipped to ultimate users, and in many instances the release liner is left in place until the adhesive is adhered to another substrate. As a result, a pressure-sensitive adhesive coated release liner potentially may experience a variety of environmental conditions including changes in temperature and humidity and must be functional over extended periods of time.
The strength of the adhesive bond formed between a silicone-based pressure-sensitive adhesive composition and a release liner tends to increase over time and upon exposure to elevated temperatures. This phenomenon is referred to as “adhesion build.” If the strength of the bond between the adhesive composition and the release liner is too great, the release liner and the adhesive composition cannot be separated from each other or can be separated only with difficulty, rendering the adhesive unsuitable for its intended purpose or frustrating the user. For articles that include silicone-based pressure-sensitive adhesive compositions, an undesirable degree of adhesion build often occurs before the end of the useful life of the article thereby effectively decreasing the useful life of the article.
A number of attempts have been made to decrease the degree of adhesion build between an adhesive and a liner. One useful method involves altering the surface chemistry of the liner by coating the liner with a surface chemistry modifier. Fluorosilicones are a common class of surface chemistry modifiers that have been coated on liners to improve their release properties. Although some of these methods have reduced the adhesion level, adhesion build continues to occur and the rate of adhesion build remains undesirable. It would be desirable to achieve a silicone-based pressure-sensitive adhesive article that includes a silicone-based pressure-sensitive adhesive composition in contact with a release liner and that can be stored for an extended period of time and exhibit a sufficiently low adhesion build such that the adhesive composition releases cleanly and relatively easily from the release liner. It also would be desirable to achieve a stretch releasing pressure-sensitive adhesive article that can be stored for an extended period of time and exhibit a sufficiently low adhesion build to the release liner such that the adhesive composition releases cleanly and relatively easily from the release liner.
Pressure-sensitive adhesive articles that are removable from a substrate through stretching are often referred to as stretch releasing pressure-sensitive adhesive articles. A number of backed and un-backed stretch releasing pressure-sensitive adhesive articles are described in literature and in patents. U.S. Pat. No. 4,024,312 (Korpman), for example, discloses a highly conformable adhesive article that includes a highly extensible and elastic backing film laminated with an adhesive layer. The adhesive article is easily stretchable and may be removed from a surface by stretching the article lengthwise in a direction substantially parallel to the surface. German Patent No. 33 31 016 discloses a high elasticity, low plasticity adhesive film based on a thermoplastic rubber and tackifying resins in which the adhesive bond can be broken by stretching the adhesive film in the direction of the plane of the adhesive bond. U.S. Pat. No. 5,516,581 (Kreckel et al.) discloses a removable adhesive article having a highly extensible and substantially inelastic backing coated with a layer of pressure-sensitive adhesive and a non-adhesive pull tab to facilitate stretch removal. The adhesive article can be removed from most surfaces without damaging the substrate by grasping the non-adhesive pull tab and stretching the article in a direction substantially parallel to the surface of the substrate. U.S. Pat. No. 6,231,962 (Bries et al.) discloses a removable foam adhesive strip that includes a backing that includes a layer of polymeric foam and a pressure-sensitive adhesive layer coated on at least one surface of the backing. A commercially available stretch releasing adhesive article is sold under the trade designation COMMAND by 3M Company, St. Paul, Minn. | {
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1. Field of the Invention
The present invention relates to a semiconductor device fabrication method of fabricating system large scale integration (LSI) devices and the like having mixed logic and memory parts, and a semiconductor device fabricated by this method. More particularly, it relates to a fabricating method of forming a gate pattern of a metal oxide silicon (MOS) transistor in logic parts in a system LSI and a structure of the gate pattern of the MOS transistor.
2. Description of the Related Art
Recently, there is a strong demand of miniaturization and multifunction in consumer electronic products and information devices. It is, accordingly, necessary to manufacture those electronic products, for example, a system LSI based on microstructure technology.
The most important problem in the above current demand is therefore to fabricate a device pattern of a MOS transistor in a logic part with a microstructure. Although various researches and developments for exposure light sources, photo resists, ultra-resolution technology, and the like have been done, at the present time the lithography (exposure) technology does not satisfy the current demand to miniaturization.
Recently, a resist sliming method has been proposed as one of technologies to fabricate a device pattern with a dimension of not more than a limitation of lithography resolution. This method can fabricate fine patterns with a dimension of not more than the limitation of a lithography resolution by performing an isotropy etching and the like for a resist pattern after the fabrication of this resist pattern.
Hereinafter; a description will be given of an example in which the resist sliming method is applied to a MOS transistor fabrication process.
FIGS. 120A-120C through FIG. 125 are plan views of a fabrication process of a MOS transistor in a logic section and sectional views thereof along lines X-X′ and Y-Y′. That is, as shown in FIGS. 120A-120C, a gate insulating film 201 is formed over a silicon substrate 200 including an element region 200a and an element isolation region 200b by a thermal oxidation method and the like. After this process, a work material film, for example, a poly-silicon film 202 as a gate electrode material film is deposited over the gate insulation film 201 by a chemical vapor deposition (CVD) method.
Following this process, a resist is applied over the poly-silicon film 202 and then dried, and a lithography process (exposure) is performed in order to form a first resist pattern, for example, a gate resist pattern 203 with a limitation dimension of the lithography (exposure) gate resist pattern forming process. In this, process, the gate resist pattern 203 is formed over the element region 200a and the element isolation region 200b. Here, the pattern section over the element region 200a is called to as a gate electrode pattern section 203a and the pattern section over the element isolation region 200b is called to as a wiring pattern section 203b.
As shown in FIGS. 121A to 121C, the gate resist pattern 203 is processed by the isotropy dry etching using O2 series gas, and as shown by dotted lines in those figures, the sliming process is performed in order to form the gate resist pattern 203′ whose dimension is not more than the limitation of the lithography (Gate resist sliming process).
Next, as shown in FIGS. 122A to 122C, the poly-silicon film 202 is etched by a reactive ion etching (RIE) method using the gate resist pattern 203′ as a mask. This process makes the gate pattern 204 having a gate electrode pattern section 204a formed over the element region 200a and a wiring pattern section 204b formed over the element isolation region 200b (Gate electrode working process).
Next, as shown in FIGS. 123A to 123C, the gate resist pattern 203′ is removed from the surface of the gate pattern 204 by O2 ashing method and the like (Resist removing process).
Thereby, it is possible to form the gate resist pattern 203′ having a pattern width that is not more than the limitation of the lithography resolution, and then possible to form the fine gate pattern 204 having a pattern width of not more than the limitation of the lithography resolution by performing the etching process for the poly-silicon film 202 as the gate electrode material film using the gate resist pattern 203′ as the mask.
After the above processes, although not shown, an impurity is doped into the surface of the silicon substrate 200 by using the gate electrode pattern section 204a as the mask in order to form the source and drain diffusion layer (designated by the dotted lines in FIG. 123B) of the MOS transistor. Following this process, the known layer insulation formation and wiring process are performed, and the MOS transistor fabrication process is thereby completed.
However, in the resist sliming process according to the related art described above, although a fine pattern of the gate electrode pattern section 204a corresponding to a line pattern can be formed, the space section in the wiring pattern section 204b is enlarged. Therefore it is necessary to relax the design rule for the space section when compared with the case not using the sliming process because the space section in the wiring pattern section 204b is enlarged by the execution of the sliming process. That is, as shown in FIGS. 124A and 124B, the dimension “t” (the distance of the adjacent gate patterns) in the space section in the wiring pattern 204b can be reduced to the dimension “to” of the lithography resolution limitation when no sliming process is performed. But, when the sliming process is performed, the dimension “t0” can be relaxed to the dimension “t0+2t1” that is obtained by adding the dimension “t0” (as the dimension of the lithography resolution limitation) and the dimension “2t1” (as the sliming values of both sides). As a result, although the related sliming method has the effect to improve the performance of the operation speed of the MOS transistor because the fine gate electrode pattern in the MOS transistor can be formed, it has no effect to reduce a semiconductor chip area because the design rule of the space section in the wiring pattern section should be relaxed when compared with the normal lithography process using no sliming process.
FIG. 125 shows a gate pattern in a dynamic random access memory (DRAM) cell. In FIG. 125, the dotted lines show a resist pattern before the sliming process and the solid lines show a resist pattern after the sliming process. The memory cell section requires a fine pattern pitch in order to increase the integration. However, when the related art sliming process is applied to the memory cell section, a space pattern dimension P1 after the sliming process cannot be reached to the limitation of a space resolution in a lithography process. This means that the dimension P2 of the space pattern in the lithography process should be relaxed. As a result, the gate pattern pitch in the memory cell section is relaxed, so that there is a possibility to cause a drawback in which the chip area of a system LSI having relatively large-scale memory cells is expanded.
That is, the sliming process has various drawbacks because a pattern for which no sliming process is necessary is also slimmed by performing the sliming process. For example, in a case that both a fine line pattern and a narrow-width space pattern are obtained, when, the line pattern is slimmed, the dimension of the narrow-width space pattern becomes also wide. Therefore it is necessary to set the dimension of the space pattern to a narrow dimension before performing this sliming process. This causes a difficulty to perform a lithography process.
As described above, although the sliming process to form a fine line pattern is well known, it is difficult to obtain a desired pattern dimension in the entire area of a same layer including various patterns, for example, a fine line pattern and a narrow space-width space pattern.
By the way, the related art also has following problems.
In a case to form a gate layer circuit pattern of a semiconductor device in which logic sections and memory sections are mixed using a combination of the exposure using an alternating phase shift mask and the resist sliming process for the logic gate section, it is necessary to performing following three exposure processes. In the first and second exposure processes as a double exposure process, the logic gate section is exposed by using the alternating phase shift mask and a trim mask in order to form the resist pattern, and the resist pattern is then slimed by the sliming process. After this process, in the third exposure process, both the memory cell section and the wiring section are exposed. This related art method must require those three exposure processes described above. That is, this related art method should perform the exposure processes of many times.
Further, with advancing semiconductor device miniaturization, it becomes difficult to form a fine pattern of the semiconductor devices. In order to solve this problem, a lithography process uses a thin film resist having a thin thickness. When a thin-film resist is used, it is necessary to perform a highly selective etching for a target etching material in order to avoid occurrence to disappear the thin film resist having a thin thickness. In the highly selective etching the target etching material is etched while protecting the resist pattern from an etching gas by adhering reaction products generated by the etching onto the resist. Hence, the amount of reaction products greatly affects a process accuracy of the target etching material. Specifically speaking, the amount of reaction products becomes increase according to increasing an etching area. For this reason, when a line pattern and the like is formed, a line width in an area having a rough line pattern becomes large when compared with that in an area of a dense line pattern. That is, in the etching method of this type, a dimension of a line pattern is greatly changed according to the density of the pattern.
Furthermore, when a sliming process (to slim a resist pattern by etching) is performed for a resist pattern, the amount of the sliming is also changed according to the density of the pattern. | {
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1. Field of the Invention
The invention relates to processing semiconductor crystal rods and somewhat more particularly to a method and apparatus for crucible-free zone melt processing of a semiconductor crystal rod whereby formation of dislocations and irregularities within the process crystal are avoided.
2. Prior Art
Semiconductor crystals, particularly those composed of silicon, are generally produced by a crucible-free zone melt process whereby a monocrystalline seed or nucleation crystal having a relatively small diameter is melt-connected, as with the aid of an induction .[.into.]. .Iadd.heating .Iaddend.coil, to an end of a relatively large diameter polycrystalline semiconductor member and a melt zone is generated at the junction of the seed crystal and the polycrystalline member and passed one or more times along the length of the polycrystalline member. The melt zone is moved by providing relative movement between the polycrystalline member and a heat source, such as an induction heating coil, which may be the same one used to melt-connect the seed crystal with the polycrystalline member or be different therefrom. In this manner, a polycrystalline member is purified of any foreign constituencies and simultaneously converted into a monocrystalline member.
In the production of semiconductor components from so-produced semiconductor materials, it is desirable that the semiconductor material be as free as possible from dislocations and other irregularities which materially interfere with the electrical properties of the semiconductor components produced therefrom. Further, the presence of dislocations, etc. within the semiconductor material decreases the life of minority carriers within such semiconductor materials.
German Auslegeschrift No. 1,079,593 (which generally corresponds to British Letters Patent No. 889,160) suggests that dislocations in rod-shaped semiconductor members may be decreased at the melt-connected juncture of the seed crystal and such semiconductor members by decreasing the cross-section of the semiconductor member at the direct proximity of such melt-connected juncture prior to the last pass of the melt zone through the semiconductor member. Dislocations which may be present in the seed crystal are thus given a chance to heal in the thus-produced thin connecting piece or bridge between the seed crystal and the semiconductor member.
German Letters Patent No. 1,128,413 (which generally corresponds to U.S. Pat. No. 3,175,891) discloses that substantially dislocation-free rod-shaped silicon monocrystals may be produced, for example, by controlling the rate or speed of travel of one or more passages of a crucible-free zone melt through the rod. This reference suggests that all passages of the melt zone start in the seed crystal and that the travel speed of the melt zone in the seed crystal should be controlled so as to be in the range of about 7 to 15 mm/min. During the last pass of the melt zone, the silicon rod cross-section at the juncture of the seed crystal and the silicon rod is constricted by a temporary relative movement of the rod ends at a speed greater than 25 mm/min. while the speed of the melt zone is steadily decreased from this constriction point until the full cross-section of the rod is attained. Thereafter, the melt zone is moved through the rod at a speed less than about 7 mm/min.
It has been noted .Iadd.that .Iaddend.monocrystalline semiconductor rods of a fairly large diameter are being produced by the crucible-free zone melt process, the rod-shaped monocrystals which grow at the seed crystal at the last passage of the melt zone tend to oscillate, particularly at the thin-connecting or bridging piece between the monocrystal and the seed crystal. This drawback is particularly acute when thick monocrystalline semiconductor rods are being produced, for example, by way of shortening or compacting during a crucible-free zone melt process. These oscillations appear to cause the development of dislocations and other irregularities in monocrystals of the material as it becomes rigid during the last passage of the melt zone through the semiconductor rod. In addition, such oscillations often cause a dripping of molten material from the melt zone or even a breakage of the thin-connecting or bridging piece between the seed crystal and the semiconductor rod, which, of course, causes an interruption in the melt zone process.
I have disclosed in German Offenlegungsschrift No. 1,519,901 a means of supporting the ends of a crystal rod at the juncture thereof with a seed crystal which comprises a finger-like support means that is positioned on the upper edge of a casing and which is axially movable and encloses the mounting for the seed crystal. However, this arrangement does not completely obviate vibrations or oscillations during the growth of very thick (i.e. having a diameter larger than 30 mm) dislocation-free semiconductor monocrystalline rods since the finger-like supports do not uniformly touch the overall round cone portion of such rod. Due to this instability, increased oscillations may be produced opposing the supporting effect desired or may even eliminate any beneficial supporting action. | {
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1. Field of the Invention
The present general inventive concept relates to an image forming apparatus. More particularly, the present general inventive concept relates to an apparatus and method to efficiently perform a printout irrespective of an insufficiency of colors contained in a toner or ink cartridge used in the image forming apparatus.
2. Description of the Related Art
Image-forming apparatuses print images provided from monitors, television sets (TVs) or other video output apparatuses. The monitors, TVs and other video output apparatuses use an RGB (Red, Green, Blue) color model, and the image forming apparatuses use a CMYK (Cyan, Magenta, Yellow, Black) color model. Hereinafter, particulars of the RGB color model and the CMYK color model will be explained.
The RGB color model is used in monitors, TVs and other video output apparatuses that implement colors by a principle of light. This color model represents colors based on the three primary colors of light, and has characteristics in that mixed colors become brighter than the colors before being mixed. Accordingly, a color representation by mixing the colors in the RGB color model is called an additive color mixture.
The CMYK color model is used in color printing. If colors are mixed in the CMYK color model, a tone of the mixed color becomes darker than the original colors. This kind of color mixture is called a subtractive color mixture. An operation of the image forming apparatus will be explained.
FIG. 1 is a block diagram illustrating a construction of a conventional image forming apparatus and a host computer.
Referring to FIG. 1, the image forming apparatus 100 includes a printing unit 102, a memory unit 104, a control unit 106, a storage unit 110, and a toner or ink cartridge unit 108. The host computer 120 includes an interface unit 122, a printer driver 124, a half-toning unit 130, a rendering unit 126, and a color matching unit 128
The printing unit 102 prints print data transferred from the control unit 106. The control unit 106 controls the components of the image forming apparatus 100 according to a control program. The memory unit 104 temporarily stores the print data which is transferred to the control unit 106 from the host computer 120, or stores information required to print the print data. The toner or ink cartridge unit 108 contains toner or ink for printing the print data. The storage unit 110 stores a residual amount of the toner or ink contained in the toner or ink cartridge unit. It will be apparent that the memory unit 104 and the storage unit 110 may be constructed into one device.
The interface unit 122 of the host computer 120 accesses to the image forming apparatus 100, and supports a communication interface between the host computer 120 and the image forming apparatus 100. The interface unit 122 may be implemented by an IEEE1284, USB, wireless, GPS or RS232C interface module or a network interface module. The interface unit 122 transmits the print data from the host computer 120, and provides the print data to the control unit 106 of the image forming apparatus 100. The printer driver 124 receives a print command to print a document (that is, print data) that a user has prepared using an application program, and transfers the print data to the rendering unit 126. The rendering unit 126 performs a rendering process for the transferred print data. The color matching unit 128 performs a color matching process for the print data for which the rendering process has been performed. The half-toning unit 130 performs a half-toning process for the print data for which the color matching process has been performed, and transfers the print data for which the color matching process has been performed to the interface unit 122.
FIG. 2 is a flowchart illustrating a conventional process of generating print data and transferring the generated print data from a host computer to an image forming apparatus. Hereinafter, with reference to FIG. 2, the conventional process of generating the print data that is performed by the host computer will be explained.
At step S200, the host computer receives a user's instructions to form an image of a specified document (print data). Generally, the user instructs the host computer to form the image using a keyboard. At step S202, the host computer performs a rendering process for the print data. At step S204, the host computer calculates a necessary amount of toner or ink of each color with respect to the rendered print data.
At step S206, the host computer compares the necessary amount of toner or ink of each color calculated at the step S204 with a stored amount of toner or ink of each color. At step S208, the host computer determines whether there is any color of which the stored amount of toner or ink is less than the necessary amount of toner or ink. If it is determined that there is any color of which the stored amount of toner or ink is less than the necessary amount of toner or ink, the host computer proceeds to step S210. If it is determined that there is no color of which the stored amount of toner or ink is less than the necessary amount of toner or ink, the host computer proceeds to step S212.
At the step S210, the host computer determines whether to continue the image forming process. If the host computer determines to continue the image forming process, it proceeds to the step S212, and, if the host computer determines not to continue, it proceeds to step S214. At the step S214, the host computer cancels the image forming process. At the step S212, the host computer performs color matching. At step S216, the host computer performs a half-toning process for the print data, and at step S218, the host computer transmits the print data to a spooler and temporarily stores the print data therein. At step S220, the image forming apparatus forms the image of the temporarily stored print data.
As described above, according to the conventional apparatus and method, the image forming is performed using only the remaining colors other than the color of which the amount of toner or ink is insufficient if the amount of toner or ink of any color necessary for the image forming of the print data is insufficient. Even if only a specified color is insufficient, a host computer displays a warning message that all of the colors are insufficient, and thus the user does not know which color is actually insufficient. | {
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Wellbores or boreholes may be drilled to, for example, locate and produce hydrocarbons. During a well development operation, it may be desirable to evaluate and/or measure properties of encountered formations, formation fluids and/or formation gasses. Some formation evaluations may include extracting a core sample (e.g., a rock sample) from sidewall of a wellbore. Core samples may be extracted using a coring tool coupled to a downhole tool that is lowered into the wellbore and positioned adjacent a formation. A hollow coring shaft or bit of the coring tool may be extended from the downhole tool and urged against the formation to penetrate the formation. A formation or core sample fills the hollow portion or cavity of the coring shaft and the coring shaft is removed from the formation retaining the sample within the cavity. The formation or core sample may then be removed from the coring shaft for further evaluation at, for example, a laboratory. | {
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Impact injuries are sustained from impacts of objects against an individual and impact of the individual against objects. Impact injuries include blunt force traumas, punctures, concussion, broken bones, damaged joints, and other medical conditions. Equipment for prevention of impact injuries has existed for many centuries in many forms, including medieval armor and ancient Egyptian helmets.
Prevention of impact injuries has led to the development of modern safety equipment, such as hardhats, batting helmets, football pads, knee-braces, and body armor such as bullet proof vests, etc. Some safety equipment useful for preventing impact injuries is bulky, cumbersome, heavy, and can limit movement. For example, football pads can limit movement and tend to be bulky. Knee or other joint braces can unduly limit range of motion. Body armor tends to be bulky, heavy, and may limit range of motion in some cases. | {
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A conventional brake pressure control device for a vehicle is disclosed in Japanese Patent Laid Open No. 8(1996)-133059. The brake pressure control device disclosed in this publication includes a master cylinder, a pressure control valve, and a changeover valve disposed between the master cylinder and the pressure control valve. The changeover valve is designed to be switched to connect the master cylinder and the suction port of a fluid pump to supply brake fluid to each of the wheel brakes from the master cylinder when the brake pedal is not operated.
This conventional brake pressure control device is applied to a diagonal dual brake circuit mainly installed on a front engine front wheel drive vehicle having a pair of brake circuits, one of which is connected to the front right wheel brake and the rear left wheel brake and the other one of which is connected to the front left wheel brake and the rear right wheel brake.
When the above described device is applied to a front-rear dual brake circuit that is primarily installed on a front engine rear drive vehicle having a pair of circuits, one of which is connected to the front wheel brakes (front brake circuit) and the other one of which is connected to the rear wheel brakes (rear brake circuit), the brake pressure increase rate generated by the fluid pump differs between the front brake circuit and the rear brake circuit because brake fluid consumption differs between the front wheel brake and the rear wheel brake. Therefore, vehicle passengers may feel uncomfortable by the brake force difference between the front and rear of the vehicle.
If two fluid pumps each having a different capacity are applied to the front brake circuit and the rear brake circuit to address the foregoing drawback, the cost of the overall brake pressure control device is significantly increased.
In light of the foregoing, a need exists for a brake pressure control device that is not susceptible to the disadvantages and drawbacks associated with other known brake pressure control devices.
It would be desirable to provide a vehicle brake pressure control device that is able to equalize brake pressure differentials between the front brake circuit and the rear brake circuit. | {
"pile_set_name": "USPTO Backgrounds"
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Spindle sanders and, in particular, spindle sanders in which the sanding drum is oscillated in a direction normal to the work table are well known in the art. The advantage of oscillating the sanding drum in an axial direction is that the wear on the sanding drum is spread over an extended area and reduces the formation of ridges on the sanded surfaces. Krueger, in U.S. Pat. No. 2,426,028, teaches an oscillating spindle sander having a vertically oriented cam to oscillate the arbor to which the sanding drum is attached. An example of another type of mechanism for oscillating a rotating arbor in an axial direction is taught by Brookfield in U.S. Pat. No. 3,886,789 in which a viscometer is oscillated in an axial direction by a cam follower disposed in a sinusoidal groove. In another example, Cuchiara teaches an annular cam for oscillating a battery powered toothbrush using an annular cam connected to the rotating shaft which engages a mating cam formed on the end enclosure. | {
"pile_set_name": "USPTO Backgrounds"
} |
The disclosure relates to a rock drilling unit, and particularly to an arrangement for changing drill rods in the rock drilling unit. The rock drilling unit includes a feed beam and a rock drilling machine arranged movably on the feed beam. The rock drilling machine has a shank for connecting drill rods to the drilling axis. Further, at least one retainer device is arranged on the feed beam.
The disclosure further relates to a method of changing drill rods in the rock drilling unit.
In mines and other work sites rock drilling rigs are used for drilling bore holes on rock surfaces. Typically the rock drilling rig includes one or more drilling booms which are provided with drilling units. In many cases drill holes having a greater length than one drill rod need to be drilled. Then two or more drill rods need to be connected to each other in order to form an extension rod. This is called extension rod drilling. Typically several drill rods are stored in a rod magazine which is arranged in the drilling unit. However, the rod magazine is large and heavy, whereby it may hamper the drilling. | {
"pile_set_name": "USPTO Backgrounds"
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After years of advances in cancer therapy, cancer remains a difficult disease to treat. Existing chemotherapeutic remedies have nonspecific toxicity, poor solubility, and multiple-drug resistance. Conventional cancer chemotherapeutic agents target the metabolic and structural machinery needed by rapidly dividing cells to maintain growth. These structurally heterogeneous agents function through a variety of mechanisms, including intercalating within the DNA of rapidly dividing cells, interrupting microtubule function, and crosslinking DNA via alkylation. However, one of the major limitations of conventional cancer therapeutics is dose-limiting side effects, largely from drug effect in non-targeted tissues. | {
"pile_set_name": "USPTO Backgrounds"
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High pressure, flexible hoses for conveying fluids under high pressure such as hydraulic oil, water, but also steam or gasses are omnipresent in all kinds of equipment and vehicles to effectively transfer motion or fluids between parts that can move relative to one another.
Typically these kind of hoses consist of an elastomer core tube that contains the fluid around which one or more reinforcement layers have been spirally wound while being radially separated by intermediate layers of elastomer material. An outer layer is generally applied on the outermost reinforcement layer for covering the reinforcement such that it does not get damaged.
The reinforcement layer is crucial to the functioning of the hose in that it does not only impart strength to the hose but also keeps the hose flexible. The reinforcement layer must be able to withstand highly variable pressures with shock waves propagating through the fluid. As hoses are many times used in harsh environments and convey aggressive fluids at high or low temperatures the reinforcement layer must maintain its properties of strength, flexibility and fatigue resistance also in these circumstances.
While in the past expectations from novel synthetic reinforcement fibers such as long chain synthetic polyamide based aramids, or ultra-high molecular weight polyethylene oriented fibres were high, the most used material for reinforcing high pressure hose is still the plain steel wire, possibly coated with an adhesive layer.
The steel wires can be applied around the core tube in a number of ways such as in: Spiralled hoses wherein the wires are wound parallel to one another in a helicoidal way. Preferably the reinforcement layers are paired and wires of members of a pair are wound in opposite directions while being separated by an intermediate polymer or elastomer layer. Or The reinforcement layer can be braided which can be described as a pair of spiral layers wound closely together without an intermediate elastomer layer. The wires of each spiral layers are grouped in ribbons, and the ribbons of one layer are interwoven with the ribbons of the other layer. The interweaving can be according a plain weave, twill weave or satin weave.
The steel wires in the hose are wound under a helix angle that is conventionally set as the angle between the tangent vector to the steel wire and the axis of the helix. When the angle is close to the so called ‘neutral angle’ the reinforcement will behave neutral when pressure is applied to the hose: the hose will neither shorten nor elongate. The neutral angle is A tan(√{square root over (2)}) which is about 54°44′.
From the mechanical point of view the hose must fulfil some basic requirements: It must have sufficient burst pressure (BP) i.e. the pressure at which the weakest wall part of a test piece yields. The burst pressure is amongst other factors directly depending on the breaking load and the number of reinforcing fibres in the reinforcement layer. Other factors are the construct of the hose: number of layers, radial positions of layers, lay angles, spiralled or braided, rubbers used, etc. A hose must be used below its burst pressure at a certain working pressure (WP). Depending on the application of the hose a safety factor is used that for hydraulic applications is generally set to 4. The pressure at which the hose is intended to be used should then not be larger than one quarter of the burst pressure. As hoses are subject to impulse pressures for example due to pumping cycle, valve closing, fluid hammer and other abuse impulse life testing is used to simulate the effect of those phenomena. During impulse life testing a piece of hose is square wave pressure loaded from near zero up to 125% or 133% (depending on hose construction) of the working pressure and back with a certain repetition rate and duty cycle. The test is either stopped due to failure of the hose or when a prescribed number of cycles has been reached. Possibly a surviving test piece is subject to a final burst test to assess the final performance of the hose.
The following prior art in the field of steel wire reinforced high pressure hoses is of particular relevance to the invention: JP 2005 291466 (Yokohama Rubber Co Ltd) describes a hose that comprises layers of steel filaments that have received a two-dimensional waveform or a three dimensional spiral shape before incorporation of the wires into the reinforcement layers of the hose. The waveform or spiral shape must be such that the wire elongates at least 0.35 at 20% of its breaking load, but not more than 15%. The purpose is to dampen pulsation waves through the hose. The wires are of equal make throughout the hose. The drawback is that not all wires may be loaded to the maximum of their capabilities. U.S. Pat. No. 4,273,160 (Parker-Hannifin) describes a flexible high pressure hose with at least two layers of stranded reinforcement, wherein the modulus of elasticity of the material within one layer increases when radially going outward. The text mentions the use of metal wires only for the outer layer, while the inner layers are made of synthetic fibres. Hence two different types of material are needed. WO 2007/020503 (Eaton Corporation) describes a high pressure hose comprising at least two reinforcement layers with different tensile strength of which the inner layer has a lower tensile strength than the outer layer. The assumption is that a lower tensile strength of the wire leads to an increased fatigue life of the steel wire and hence an increased pulse life. Different tensile classes of steel wire are used within a single hose. No mention is made of the elongation at break of those wires. EP 0200253 (Bekaert) describes a method to condition a hose reinforced with steel wires that all have been stress relieved in order to have a higher elongation at break. By applying a high ‘preconditioning pressure’ of more than 90% of the burst pressure of the hose, the wires are permanently elongated at the optimal load sharing. The method is an additional extra treatment that is not without risk.
The prior art hoses therefore suffer from the mentioned drawbacks that the inventors solved with the below described innovative high pressure hose. | {
"pile_set_name": "USPTO Backgrounds"
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In recent years, many portions of a vehicle are operated by electric motors, and thereby numbers of the electric motors and electronic control units thereof are increased. Many efforts for increasing effective inside space of the vehicle have been made in order to provide a comfortable space to a user. Accordingly, it becomes a problem to keep space for the electric motors and the electronic control units thereof. It is, therefore, an important issue for making the electric motors and the electronic control units thereof smaller in size.
For example, an electronic control unit used for an electric power steering system for the vehicle is arranged in a space of an engine compartment or behind an instrument panel. Since the electronic control unit for the power steering system drives the electric motor with large electric current (around 100 A), heat generated at switching elements is increased. Therefore, a high heat radiating structure is necessary in order to make the electronic control unit of this kind smaller in size.
In prior arts, for example, as disclosed in the following Japanese patent publications, an electric connecting pattern for heat radiation is provided on a printed circuit board so as to radiate heat of electric and/or electronic parts mounted on the printed circuit board. According to the prior arts, although the electric connecting pattern for the heat radiation is provided or electric and/or electronic parts are effectively arranged on the printed circuit board, desired heat radiating performance can not be obtained. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates generally to golf clubs, and more particularly to connection of a golf club head to a shaft to achieve certain advantages.
Many efforts have been made to reallocate metallic weight from the hosel area of a golf club to the head itself, in order to achieve higher energy availability for transfer when the club is swung. Such greater energy or momentum is then transferred to the golf ball when struck. This requires, for example, reduction of metal at the hosel area of the club.
Such efforts have included configurations wherein a shaft passed through the head of a persimmon wood. Typical of such configurations were: Wilson's staff model "Dynopower Fluid Feel" wood, produced around 1957; Wilson's "Helen Hicks" wood, produced in the 1920's; and certain MacGregor woods, produced in the late 1930's. See also U.S. Pat. No. 4,995,609 entitled "Iron Golf Club Heads" assigned to Callaway Golf Company, disclosing a hosel characterized by reduced mass or weight.
No way was known, to our knowledge, to connect a shaft to a golf club iron head, where the shaft passed into proximity to the bottom of the head and was reduced in diameter at or near the bottom of the head so as not to interfere with an edge or edges of the sole; also, no way was known to connect such a shaft to a non-constant tapered bore in an iron hosel to provide a tight interference fit along localized extent of the shaft and bore, upon axial assembly, enabling very good tactile "feedback" sensing, to the player, of head-to-ball impact, and also providing annular space for adhesive reception between the shaft and bore near the bore taper.
Further, locking of the collapsed end of a shaft to a bore, by local expansion of the collapsed end, was not known. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a control mechanism for an instruction pipe in a processor that maintains timing synchronism between the instruction pipe and other elements outside the instruction pipe.
Execution logic in modern processors have begun to incorporate multiple instruction pipes. Each instruction pipe may include sufficient circuitry to execute most program instructions independently of the other pipes. Thus, a processor having multiple instruction pipes may perform nearly perfect parallel execution of program instructions.
It may not be desirable for instruction pipes to operate with complete independence from each other. For certain operations, greater efficiencies may be achieved by having the instruction pipes share access to other logic circuits. By way of example, it may be preferable for multiple instruction pipes to share a single Return Stack Buffer (“RSB”). As is known, an RSB is a buffer that stores forward and return pointers associated with call and return instructions. When a processor executes a call, it pushes an address associated with the call instruction to the RSB, typically the address of an instruction immediately following the call instruction, and begins execution at another program instruction at an address specified in the body of the call instruction. When a processor executes a return instruction, it retrieves an address from the top of the RSB and commences program execution at the retrieved address. Even in a processor having multiple instruction pipes, it may be more efficient to provide a single RSB for all instruction pipes rather than to provide a separate RSB for each of the instruction pipes. Because RSBs typically are not used every clock cycle, sharing the RSB improves utilization and reduces cost over a double-RSB design, for example.
In one implementation, an RSB may be provided within a first instruction pipe. Other instruction pipes in the processor may communicate with the RSB to store addresses therein for call instructions or to retrieve addresses therefrom for return instructions. However, this implementation raises a variety of timing problems.
A first timing problem arises because one RSB must be shared among a variety of instruction pipes. For N instruction pipes in a processor, each instruction pipe may enjoy utilization of the RSB reduced on a pro rata basis (1/Nth of the RSB's total capacity). If an instruction pipe issues read or write requests to the RSB in excess of its pro rata share, the requests may be dropped. This would result in processor failure.
A second timing problem may arise due to round-trip communication latencies between an instruction pipe and the RSB. Requests must propagate from an instruction pipe to an RSB, be acted upon by the RSB and results therefrom must return to the instruction pipe. An instruction pipe that does not account for this round-trip latency during operation may act upon invalid data. Again, this would result in processor failure.
Accordingly, there is a need in the art for a timing control mechanism for use in instruction pipes to conform operation of the instruction pipe to timing limitations that may arise when interfacing the instruction pipe with external elements. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention is directed to sterilization wrap materials. More particularly, the present invention is directed to multi-plied materials made from individual sheets which are fused together so as to be suitable for use as a sterilization wrap for wrapping surgical instruments and supplies for sterilization and storage in conjunction with surgical procedures and for other applications such as packaging items for bone marrow units.
Personnel in the Central Service Room (CSR) or the Sterile Processing Department (SPD) of hospitals are commonly charged with the responsibility of packaging surgical supplies to ensure that the sterility of the packaged contents are maintained all the way from sterilization to the point of reuse. Several activities are involved in the task of sterile supply delivery to the operating room and other units.
Much of the surgical instruments and supplies used in the operating room are reusable. These supplies typically include such things as clamps, scalpel blade handles, retractors, forceps, scissors, surgeons towels, basins and the like. All of these supplies must be collected after each procedure and sterilized before they can be used again in another procedure. To this end, the supplies are placed in stainless steel instrument trays, and soft goods such as surgeons towels, drapes, and gowns are prepared for packaging. Then, the trays and package contents are each generally wrapped with two sheets of material commonly referred to as sterilization wrap.
The sterilization wrap is usually a woven or nonwoven material which when wrapped around the tray or package contents in a certain prescribed manner will permit the entry of sterilizing vapor/gas or other medium to sterilize the contents of the tray while denying the ingress of contaminants such as bacteria and other infectious causing materials or their vehicles after sterilization. Generally, the two primary means for sterilizing instruments are autoclaving with steam and ethylene oxide sterilization.
Using a wrapped tray as an example, once the wrapped tray and its contents have been sterilized, the wrapped tray is transported to the point of use, typically an operating room, or is stored until it is ready to be used. During storage and transfer to the operating room, the wrapped tray may be handled several different times. Each time the wrapped package is handled, there is a potential that the sterile nature of the package contents can be compromised. The two most common ways the wrapped package can be compromised are a tear or other breach of the wrapping material, and wetness or foreign materials identified on the outer wrapper, which would warrant a premature unwrapping.
In order to promote and maintain the sterility of the packaged contents, the Association of Operating Room Nurses (AORN) has developed certain recommended practices for the wrapping and handling of in-hospital processed packages. It is common practice among many hospitals as recommended by the AORN to "double wrap" in-hospital processed packages. A primary method of double wrapping is "sequential" in nature in that the package contents are first wrapped by one sheet of sterilization wrap and then wrapped again by another sheet of sterilization wrap. Another method of double wrapping is "simultaneous" in nature in that the package contents are wrapped by two sheets of sterilization wrap at the same time. That is, two sheets of sterilization wrap are aligned one on top of the other, and the item to be wrapped is placed on top of the two sheets, then the item is wrapped by both sheets of material at the same time.
Studies have been used to track packages from initial wrapping, all the way through sterilization, storage, handling, transfer, unwrapping and ultimate reuse. These studies indicate that the frequency of compromising wrapped items due to tears or holes has been reduced because of improved handling and storage techniques and because of improved sterilization packaging products. One of the main thrusts behind such efforts has been economics. Every time a sterile package is compromised, it must be taken out of circulation, unwrapped, rewrapped, and resterilized before it can properly be reused. This wastes time and money.
While the frequency of compromising wrappers has been reduced thus resulting in the saving of time and money, the use of simultaneous wrapping techniques would further increase the time savings in wrapping and opening packages and thus result in a still greater cost savings. Simultaneous wrapping takes less time than sequential wrapping and recent research in hospitals has shown simultaneous wrapping to be just as effective as sequential wrapping in maintaining sterility absent a breach in the wrap which is generally independent of the manner of wrapping.
Even though the hospital staff may desire to simultaneously wrap instead of sequentially wrap, the time it takes to set up the outer and inner sheet wrappers and the awkwardness of manipulating loose wrappers during simultaneous wrapping can offset the time savings hoped to be achieved when attempting to move away from sequential wrapping. Consequently, if a product existed which provided the appropriate inner and outer sheet combinations and eliminated the awkwardness of keeping the two sheets together during the package wrapping and opening processes, then a simultaneous packaging system would deliver the benefits desired including time savings and targeted engineered inner and outer sheet performance.
In conjunction with the manner in which the packages are wrapped, the material used for wrapping is also important. As mentioned above, the two most common wrapping materials are woven materials such as cloth (cotton/polyester), nonwoven materials such as KIMGUARDO.RTM. Sterile-Wrap (polypropylene) from Kimberly-Clark Corporation of Neenah Wisconsin and Bio-shield CSR Wrap (wood pulp/polyester) from Baxter Healthcare Corporation of Deerfield, Illinois. One version of the Baxter sterilization wrap is a product called DualWrap.RTM. Sterilization Wrap, which includes an inner sheet of wet laid paper (cellulose) and a separate outer sheet of spunlaced or hydroentangled pulp/polyester. The inner and outer layers are provided in a stack of loose, unattached sheets in which the inner and outer sheets are alternated.
Whatever the material is that is being used as sterile wrap, it should be noted that when wrapping two sheets at the same time, it is important that the wrapping materials provide good barrier properties to maintain package sterility and good strength properties so that tearing or other forms of breaching are held to a minimum. If the outer and inner sheets of the double wrap are to have different properties, then it is important that the system be visually identifiable so that the user can determine which wrapper is the outer sheet and which wrapper is the inner sheet. Consequently, there is a need for a new sterilization wrap system that actually reduces the time for packaging and opening and delivers outer and inner sheet engineered performance in a simple identifiable and easy to use fashion. Such attributes are provided by the present invention as will become more apparent upon a further review of the following specification, claims and drawings. | {
"pile_set_name": "USPTO Backgrounds"
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In a typical commercial film-processing operation for the development of photographic film received from amateur photographers, the orders are initially deposited by the individual customers at commercial locations designated as dealers, such as drug stores, supermarkets, or photographic equipment stores, and then shipped to the central processing laboratory where the undeveloped films are developed and prints made from the developed negatives. Typically, the undeveloped film is delivered to the processing laboratory in an envelope that contains information as to the identity of the individual customer as well as the identity of the dealer who sent it to the processing laboratory. After the film is separated from the envelope and developed, the film and the corresponding prints are placed in the original package and returned to the dealer for eventual pickup by the individual customer.
For reasons of efficiency, the film from a number of customers is processed in a single batch and, though the film and the envelopes are separated during the processing operation, they are maintained in their original batch sequence so that at the end of the developing process the prints can be correlated with the matching envelopes. In order to protect the developed materials, the prints and negatives are first placed in a wallet prior to being put in the original customer envelope.
Rather than using a generic form of wallet, most dealers desire personalization of the wallets to include identification of the dealer or other graphic or textual material by the dealer. This means that it is necessary that the wallets be correctly matched with the customer's negatives and prints as well as the order being matched to the envelope. In order to accomplish this task, machine-readable codes are employed on the envelope so that, as the undeveloped film is removed from the envelope, it can be coded and tracked through the developing process. The code also can be used to identify the dealer from which the order originated. According to one method, the machine code is initially read from the envelope by the developing laboratory as the film is first removed from the envelope. A custom wallet corresponding to the dealer identified by the code is then selected for the order and held with the order envelopes during the developing process. When the prints are finished, they are placed in the waiting preselected wallet along with the developed negatives. This method has a number of disadvantages.
First, it is not easily determinable at the beginning of processing how many finished prints will be contained in a given order. Consequently, after processing, when a customer order is found to contain a large quantity of prints, extra wallets will be required. Because the above-described method preselects the wallets before processing, the packaging process will have to be stopped and an extra wallet obtained or a generic wallet feeder will need to be used to accommodate the extra prints. Shutting down and restarting the assembly line take valuable time and detract from the production output rate of the lab, thus severely affecting profitability of the lab and causing customer dissatisfaction due to late delivery of orders. Also the use of generic wallets defeats the purpose of the method, since it does not contain the dealer-selected imprint. A further disadvantage is that any wallets that are damaged or found to be defective cannot be easily replaced without productivity loss. Another disadvantage of preselecting the wallet prior to production of the prints is that the wallet cannot be partially printed on demand because it is unknown exactly how many wallets will be needed unless prior estimates are made based on film length and order type. This method does not provide for easy custom selection of the graphics or text to be printed on the wallet during the packaging process, thus limiting the dealer's options. | {
"pile_set_name": "USPTO Backgrounds"
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This invention generally relates to a vehicle occupant restraint system for a three-point seat belt system. More specifically, the invention relates to a system having means for determining if a seat belt is being used properly by an occupant.
It is well known in the art that using a three-point seat belt, in a vehicle, will aid in preventing injury to an occupant. A three-point seat belt system typically comprises a retractor, D-ring or belt guide, a buckle and associated tongue, lower belt restraint anchor and seat belt webbing. Generally, the seat belt webbing (or seat belt) is divided into a lap (belt) portion and a shoulder (belt) portion. The proper or intended use of the seat belt is for the occupant to wear or to install the shoulder belt portion across his upper torso and the lap belt portion across his lap. It is also known that some occupants, for whatever reason, occasionally place the shoulder belt portion belt behind their backs with the lap belt portion buckle about the waist. If the seat belt is utilized in this improper manner the vehicle occupant's upper torso cannot be restrained during a crash event. This improper use of the seat belt will minimize the occupant restraining qualities of the restraint system. This improper use is also important in relation to the operation of a "smart" air bag restraint system which controls the inflation of the air bag during an accident. With the seat belt improperly used the occupant's upper torso, during a crash, will move forwardly into the inflating air bag. With knowledge of the state of use or misuse of the seat belt this information can be used to lower the inflation rate of the inflating air bag or negate the operation of the air bag.
One of the objects of this invention is to provide a system that is capable of determining if an occupant is not wearing the seat belt as it was designed to be used. It is a second object of this invention to provide at a minimum, a warning signal to reinforce to the occupant (or at least to a responsible adult) of improper seat belt use so that the seat belt can be placed properly about the occupant. Finally, it is an object of the present invention to modify the operation of other on-board safety restraint systems, such as an air bag system, based on the state of use or misuse of the seat belt.
Many other objects and purposes of the invention will be clear from the following detailed description of the drawings. | {
"pile_set_name": "USPTO Backgrounds"
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At present, limestone desulfurization process and ammonia-based desulfurization process are mainstream processes in the whole world for removing sulfur dioxide from gases. In the limestone desulfurization process, large quantities of waste water and gypsum residues are produced during desulfurization, and a lot of investment and operating costs are required to treat these waste water and waste residues. Also, in the limestone desulfurization process, while 1 ton of sulfur dioxide is removed, about 0.7 ton of carbon dioxide is produced synchronously. With ammonia-based desulfurization process, basically no waste water or waste residue is produced, and added ammonia desulfurizer is converted into a useful ammonium sulfate fertilizer, thus it is more environmentally friendly. However, the existing ammonia-based desulfurization process often has the problems, such as ammonia escape, aerosol formation, etc.
Chinese patents CN 1283346C and CN 1321723C disclose a process for removing SO2 from coal-fired flue gas by using ammonia as a removal agent, in which the SO2 concentration in the clean gas is less than 100 mg/Nm3. However, the amount of ammonia escaping in the clean gas can be up to 12 mg/Nm3.
Chinese Patent CN 100428979C discloses an ammonia-based desulfurization process with crystallization inside a tower and an apparatus thereof, wherein the desulfurization tower is designed to be of a multi-section structure, successively including an oxidation section, a crystallization section, a cooling absorption section, a main absorption section, and a dehydration-demisting section from bottom to top. In the process, the evaporating ability of flue gas is utilized for crystallization to reduce operation energy consumption, the SO2 concentration in the clean gas is less than 200 mg/Nm3, and the ammonia content in the clean gas can be as low as 3 mg/Nm3.
Chinese patent application No. CN 201710154157.3 discloses a method and a device for ammonia-based removal of sulfur oxides and dust from gas, wherein the device consists of a gas purification and removal system, an oxidation system, an ammonium sulfate post-processing system, an ammonia supply system and an auxiliary system, and uses a process of multipoint ammonia addition and multi-stage control, thereby significantly inhibiting ammonia escape and aerosol formation, and achieving efficient desulfurization and dedusting effects.
Chinese patent application No. CN 201610322999.0 discloses a pH-based automatically adjusting ammonia addition system, mainly including a control cabinet, an aqueous ammonia tank, a first aqueous ammonia pump, a second aqueous ammonia pump, a pressure transmitter, an electromagnetic flowmeter, an electric control valve and a pH transducer, wherein the control cabinet is respectively connected to the pressure transmitter, the electromagnetic flowmeter, the electric control valve, and the pH transducer; the control cabinet is connected to the first aqueous ammonia pump and the second aqueous ammonia pump; the inlet end of the first aqueous ammonia pump is connected to the aqueous ammonia tank and the outlet end of the first aqueous ammonia pump is respectively connected to an inlet of an ammonia addition chamber and an inlet of a circulating pump; the first aqueous ammonia pump is respectively connected to the pressure transmitter, the electromagnetic flowmeter, the electric control valve and the pH transducer; the inlet end of the second aqueous ammonia pump is connected to the aqueous ammonia tank and the outlet end of the second aqueous ammonia pump is respectively connected to the inlet of the ammonia addition chamber and the inlet of the circulating pump; the second aqueous ammonia pump is respectively connected to the pressure transmitter, the electromagnetic flowmeter, the electric control valve and the pH transducer; and the electric control valve is respectively connected to the inlet of the ammonia addition chamber and the inlet of the circulating pump.
An automatic ammonia-adding system with stable and reliable system operation, a high automation degree and a simple process and being applicable to an ammonia-based desulfurization device is still required to achieve automatic multipoint ammonia addition and multi-stage control in the ammonia-based desulfurization device, and inhibit ammonia escape and aerosol formation.
It would therefore be desirable to provide improved apparatus and methods for adding ammonia to a flue gas desulfurization system to overcome shortcomings in the prior art. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates generally to switch fabrics, and specifically to efficient switching of packets within switch fabrics.
The computer industry is moving toward fast, packetized, serial input/output (I/O) bus architectures, in which computing hosts and peripherals are linked by a switching network, commonly referred to as a switch fabric. A number of architectures of this type have been proposed, culminating in the xe2x80x9cInfiniBand(trademark)xe2x80x9d (IB) architecture, which has been advanced by a consortium led by a group of industry leaders (including Intel, Sun Microsystems, Hewlett Packard, IBM, Compaq, Dell and Microsoft). The IB architecture is described in detail in the InfiniBand Architecture Specification, Release 1.0, which is available from the InfiniBand Trade Association at www.infinibandta.org and is incorporated herein by reference.
As in other packet networks, each InfiniBand packet carries a media access control (MAC) address, known in InfiniBand parlance as a Local Identifier (LID), which is used by switches in the fabric to convey the packet to its destination. Each InfiniBand switch maintains a Forwarding Database (FDB), listing the correspondence between the LIDs of incoming packets and the ports of the switch. When the switch receives a packet at one of its ports, it looks up the LID of the packet in its FDB in order to determine the destination port through to which the packet should be switched for output. Since the LID field is 16 bits long, the FDB may have up to 64K (216) entries. The InfiniBand standard specifies that the first 48K entries in the FDB are used for unicast packet LIDs, while the final 16K entries are reserved for multicast LIDs. The need to look up every incoming packet in the 64K FDB places a strain on processing resources in the switch, making it difficult to maintain wire-speed switching operation.
It is an object of the present invention to provide improved devices and methods for switching packets in a switch fabric.
It is a further object of some aspects of the present invention to enhance the speed with which a switch in a switch fabric or other network can process a packet.
It is yet a further object of some aspects of the present invention to enhance the versatility of switch devices used in a switch fabric.
In preferred embodiments of the present invention, each port in a high-speed switch comprises a forwarding database cache, referred to hereinafter as a FDB cache, preferably comprising a two-way set-associative cache. The cache entries identify the respective output ports to which the switch is to send packets with certain MAC addresses. These port assignments are read into the cache from a much larger FDB, such as the 64K-entry FDB used in InfiniBand switches.
When a packet arrives at an input port of the switch, the port looks up the destination MAC address of the packet in its FDB cache, preferably using a few of the least significant bits of the address as the lookup index. When the MAC address matches the target stored in the cache for the given index (i,e., when there is a cache hit), the switch sends the packet to the output port indicated in the cache. The port thus saves considerable processing time by avoiding having to read the port from the FDB itself, as well as conserving bandwidth used in FDB access. Since it is common in a switch fabric for a sequence of packets to be sent along the same route, the likelihood of a cache hit is high. In the event of a cache miss, the input port looks up the MAC address in the FDB. Preferably, the input port inserts the new MAC address and its corresponding port in the cache, most preferably replacing the least-recently-used (LRU) entry having the same index as the current MAC address.
In some preferred embodiments of the present invention, the FDB cache also includes one or more control bits for each entry. Preferably, one of the control bits is a xe2x80x9cforce-hitxe2x80x9d bit, which causes the input port to switch incoming packets to the output port indicated in the cache even when the MAC address of the packet does not match the cache target address. In one of these preferred embodiments, the caches at one or more of the ports are loaded so as to direct all incoming packets to one of the output ports to which a host is connected, and the force-hit bits are set. As a result, all of the incoming packets at these ports will be directed to the host for processing. This technique can be used, for example, to configure the switch and host to serve as a router, thus enhancing the versatility of switching devices using the FDB cache.
There is therefore provided, in accordance with a preferred embodiment of the present invention, a device for switching packets in a network, including:
a switching core;
a plurality of ports, coupled to pass the packets from one to another through the switching core, the ports including, with respect to each packet among the packets switched by the device, a receiving port, coupled to receive the packet from a packet source, and a destination port, to which the packet is passed for conveyance to a packet destination; and
one or more cache memories, respectively associated with one or more of the ports, each of the cache memories being configured to hold a forwarding database cache for reference by the receiving port with which the cache memory is associated in determining the destination port of the packet.
Typically, the packets include respective packet addresses, such as media access control (MAC) addresses, and the forwarding database cache includes entries indicating the destination port for each of a selected plurality of the packet addresses. Preferably, the entries in the forwarding database cache are arranged in one or more tables, which are indexed by a segment of the packet addresses. Most preferably, the segment of the packet addresses includes a predetermined number of the least significant bits of the packet addresses. Additionally or alternatively, the one or more tables include at least two tables.
Further additionally or alternatively, each of the entries includes a target field, corresponding to at least a portion of one of the packet addresses with which the entry is associated, and the target field is compared to the portion of the packet addresses to determine that a cache hit has occurred, whereupon the receiving port reads the destination port from one of the tables. Preferably, when the cache hit does not occur with respect to one of the packets, the destination port is read from a forwarding database outside the cache memory. Most preferably, the destination port read from the forwarding database outside the cache memory is entered in the cache in place of a least recently used one of the entries having a given index.
Preferably, the forwarding database cache includes one or more tables including entries to which the receiving port refers the packets that it receives, each such entry including a target field and a data value indicating the destination port to which the packet should be passed when the packet matches the target field.
In a preferred embodiment, at least some of the entries further include a force-hit flag, such that when the force-hit flag is set in the entry to which the packet is referred, the packet is passed to the destination port indicated by the entry even when the packet does not match the target field. Preferably, the entries in at least one of the one or more tables are configurable so that the data value for all of the entries can be set to indicated the same destination port, and the force-hit flag of all of the entries can be set so that all of the packets received at the receiving port are passed to the same destination port. Most preferably, the one or more cache memories include a multiplicity of cache memories respectively associated with a multiplicity of the ports, and wherein the entries in the multiplicity of the cache memories can be set so that all of the packets received at the multiplicity of the ports are passed to the same destination port. Further preferably, the device includes a host processor, coupled to the destination port so as to receive the packets from the multiplicity of the ports, and to process the packets so as to route them through the network.
Preferably, the device also includes a device memory, configured to hold a forwarding database, from which information is read for caching in the one or more cache memories.
There is further provided, in accordance with a preferred embodiment of the present invention, a method for switching packets in a network, including:
providing a forwarding database containing information indicating a destination port for each of the packets that is received at one of a plurality of ports of a switch in the network;
copying a subset of the information in the forwarding database to a forwarding database cache in a cache memory associated with each of one or more of the ports of the switch;
reading the information from the cache memory at one of the ports, responsive to receiving one of the packets at the port, in order to determine the destination port for the packet; and
passing the packet through the switch to the destination port.
The present invention will be more fully understood from the following detailed description of the preferred embodiments thereof, taken together with the drawings in which: | {
"pile_set_name": "USPTO Backgrounds"
} |
Slips are known in the downhole drilling and completions industry for anchoring components in a borehole. Slips are generally wedge-shaped devices that have teeth or other protrusions for “biting” into a tubular wall, typically a casing, as load is applied to the slips by components that are being anchored by the slips. When no longer needed, it is common to remove the components by milling or drilling operations. Current slip assemblies may include, e.g., a sleeve or series of segmented wedges made of cast iron or other materials that are difficult to remove by drilling or milling. The drilling/milling operations are time consuming and damaging to the bits used. Also, large chunks of cast iron or other materials often remain in the borehole after milling and are very difficult to fish out. As a result of the above, advances in slip assemblies are well received by the industry. | {
"pile_set_name": "USPTO Backgrounds"
} |
Dielectrically isolated island structures are commonly employed in integrated circuit architectures for supporting a variety of circuit components, such as bipolar transistor devices, junction field effect devices, DMOS circuits, etc. In a typical (NPN) bipolar configuration, shown in FIG. 1, a high impurity concentration (N+) buried subcollector region 11 is formed at the bottom of an island (e.g. silicon) region 10 that is dielectrically isolated from a support substrate 12 (e.g. silicon) by means of a layer of insulator material (e.g. silicon oxide) 14 therebetween. The thickness of subcollector region 11 may be on the order of five to fifteen microns, depending on how heavily doped it is and to what magnitude of Dt product it is subjected during wafer processing. The thickness of the N- island 10, in the upper surface of which a P base region 15, an N+ emitter region 16 (formed in base region 15) and an N+ collector contact region 17 are formed, must be sufficiently large to support the base-collector depletion region layer without causing the peak field in the depletion layer to exceed the field at which the transistor goes into collector-emitter breakdown with the base open circuited, BVCEO. For a 100 V BVCEO NPN device having an HFE of 400, an N-thickness beneath the base, on the order of ten microns, is required. The minimum resistivity for such a device is about 10 ohm-cm. With a collector-base junction depth in the range of two to eight microns, minimum island thickness will therefore be relatively large (on the order of 22 microns) and therefor costly to manufacture.
The large size of such thick islands is also due to the fact that their sidewalls are sloped or inclined as a result of the application of an anisotropic etchant through a photolithographic mask the size of which defines the bottom of the island. The minimum front surface dimension of the finished island cannot be less that the minimum bottom dimension plus two times cot a times the island thickness, where a is the angle between the island sidewall and the island surface. This angle for typical dielectric isolation fabrication techniques using <100> oriented wafers is on the order of 55 degrees. As a consequence, in the case of the above-referenced island having a minimum thickness of 22 microns, the minimum island width will be 31 microns, plus a minimum bottom dimension on the order of 10 microns, yielding a minimum lateral island dimension of 41 microns for a 100 V buried layer NPN transistor. As this width is considerably greater than that normally attributed to small components, it effectively represents wasted space. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to a method and apparatus for controlling a crimping process serving for the connection of a contact with a conductor, wherein a crimping tool of a crimping press is movable from a starting position into a crimping position and subsequently into an end position.
Equipment for producing a crimped connection has become known from U.S. Pat. No. 5,966,806. A motor drives an eccentric shaft which moves a carriage with crimping tools up and down. An encoder driven by means of the motor shaft serves for positional determination of the crimping tool. The crimp contact to be connected with a conductor end lies on a stationary anvil, wherein lugs of the crimp contact are plastically deformed on downward movement of the crimping tool and produce the connection to the conductor. The position of the crimping tool in the crimping region is measured by means of a height sensor, wherein the sensor signal is used independently of the encoder signal. At the same time the crimping force is measured on the basis of the motor current. The measurement values are compared with reference values. The comparison enables a statement about the crimp quality.
Although an encoder and a height sensor are present, only a relatively imprecise statement about the crimp quality can be made, because external influences as well as the degree of elasticity or rigidity of the mechanical driven elements are not taken into consideration.
The present invention avoids the disadvantages of the known equipment and is accordingly directed to a method and apparatus in which the crimp quality of a crimped connection can be improved.
The advantages achieved by the invention are essentially to be seen in that alteration of the crimping press is not necessary for processing different crimp contacts by different tool strokes. The crimping height and the crimping stroke are adjustable. Moreover, the crimping press control recognizes the exact tool position each time the press is activated, whereby a simple evaluation of the crimping force versus crimping stroke can be made and other machines participating in the crimping process can be synchronized.
The crimping press according to the invention operates with two measuring systems, by means of which a regulation of the drive with respect to position or crimping height regulation can be obtained. A rotative measuring system is coupled with a linear measuring system. The rotative measuring system enables a high positioning dynamic, because no dead times, caused by play in gears, levers or slides, are present. The linear measuring system enables precise crimp height regulation. Mechanically-caused tolerances of the crimping press, which may be due to, for example, crimping force or temperature fluctuations, are compensated for by the crimp height regulation. With the crimp height regulation the eccentric of the crimping press moves an angular range between 0xc2x0 and 180xc2x0 as limits. The crimping press stops at the lower dead center and subsequently reverses. Upper and lower dead center positions can be moved to as desired within the 0xc2x0-180xc2x0 angular range according to the respective crimping tool and crimp contact utilized. Intermediate stop positions are also possible. For realization of this feature only a regulated axis is necessary, and the carriage stroke or crimping height can be programmed. Moreover, the course of the crimping force as a function of the crimping stroke can be represented exactly and is usable for quality control purposes. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to generally a machine for winding coils and inserting the same into the slots of a magnetic core of a rotary electric machine and more particularly a machine for winding coils and inserting the same along with wedges into the slots of a magnetic core of a rotary electric machine.
The assembly of magnetic cores such as stators of rotary electric machines includes a step of inserting into the slots of a stator the coils which have been previously wound and a step of inserting the wedges into the slots.
It has been well known in the art that especially when the coils consisting of many turns of a fine conductor are inserted into the stator core of a motor, it is by far preferable to insert both the coils and wedges simultaneously than separately because better performance or qualities of the coils may be maintained; that is, the disconnection of the coil may be minimized; the degradation of the insulation due to the damage to the conductor may be prevented; and the coils may be securely held in the slots by the wedges.
There has been devised and demonstrated a machine capable of simultaneously inserting all the coils and wedges into a stator core. This machine is provided with a plurality of blades which are extended through a stator core and contact the inside peripheral surface thereof so as to guide the coils towards the slots and a plurality of wedge guides which contact with one of the end faces of the stator core so as to guide the wedges towards the slots. The coils to be inserted are previously wound by a separate winding machine and are inserted between the blades according to a predetermined pattern. Thereafter they are inserted into the slots along with the wedges in the manner described above.
However the coil and wedge inserting machine of the type described above has some defects to be described below. When the edgewise wound coil is removed from the bobbin of the winding machine and inserted into the insertion tooling of the coil insertion machine, the coil is disturbed so that when the coil is inserted into the slots, the conductor of the coil is trapped between the stator core and an inserting means and is cut off and the coil cannot be snugly inserted into the slots and securely held by the wedge, thus resulting in the rejection of the finished product. In addition, manual labor is needed to remove the coil from the bobbin and mount it on the insertion tooling. Furthermore, the productivity is low because the connections between the crossover leads are needed after the insertion.
As disclosed for instance in U.S. Pat. No. 2,934,099, there has been invented and used a machine capable of winding a coil and directly inserting it into the slots of a stator core. With this machine, the coils for respective poles are formed individually around bobbins. As a result, the simultaneous insertion of the coils and wedges is impossible. In addition, after the coils and wedges are inserted, the connection between the crossover leads is needed. Furthermore the winding step and the insertion step must be alternately carried out for respective poles. Thus, this machine has a low productivity and a low rate of operation.
As disclosed for instance in U.S. Pat. No. 3,817,295, there has been also invented and used a machine wherein there is provided an inserter tooling consisting of a plurality of blades with different heights and supporting means disposed radially outwardly of the inserter tooling; and a coil is wound around a bobbin formed by two of the blades and one of the supporting means, the wound coil being directly inserted into the slots of a stator core.
The last mentioned machine of the type described above has also a low productivity or a low efficiency because of the following reasons. Firstly, each time a coil for one pole is formed, it must be immediately inserted into the stator. As a result, many insertion steps are needed. In addition, the connection between the crossover leads is still needed. Furthermore since the blades are not uniform in height, the wound coils are increased in length. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The invention relates to a method of impregnating porous work-pieces pieces, i.e. filling the pores of the workpiece with a medium which is liquid at least during the impregnation. More specifically, the invention relates to the impregnation of sintered workpieces of ceramic or in particular of carbon material, for example graphite, which are used as sliding bearings or as electrical sliding contact members such as carbon brushes or collectors. The workpiece may be impregnated with a great variety of impregnating agents for various purposes, for example with oil or grease for improving the sliding properties, with synthetic resin for improving the mechanical strength, or with metal or metal alloy for improving the electrical conductivity.
2. Description of the Related Art
The usual method of impregnating porous workpieces consists of dipping the workpiece into the liquid impregnating agent, the impregnating agent being sucked into the pores of the workpiece. If the impregnating agent is not naturally liquid, it is used in the form of a liquid solution or in the form of a melt.
Vacuum-pressure impregnating is an improvement of immersion impregnating in which the workpiece, prior to immersion into the impregnating agent, is exposed to a vacuum to make the pores void of air. After immersing the workpiece the impregnating agent is subjected to pressure to force the impregnating agent into the pores of the workpiece. This prior art impregnating method has at least the following disadvantages:
The impregnating, including the necessary preparation, for example arranging the workpieces in layers in the impregnating container, requires a great deal of time (typically for about 2 to 8 hours).
In spite of using vacuum and pressure it is difficult to obtain a pore filling which is uniform over the entire volume of the workpiece, i.e. homogeneous and complete.
Following the impregnation a complicated subsequent cleaning is necessary to remove impregnating agent residues from the surface of the workpiece. The necessary mechanical and/or chemical cleaning steps are expensive, time-consuming and frequently involve considerable environmental contamination.
Briefly stated, one preferred embodiment of the method in accordance with the present invention places the porous workpieces into a divided, tightly closable die tool, similar to that used for injection moulding or diecasting. Cavities for the porous workpieces in the die tool are configured to closely surround the workpiece on all sides. Impregnating material is injected into the clamped die tool under sufficient pressure to fill the pores of the workpiece.
It has surprisingly been found that a usual injection moulding machine or a diecasting machine can be employed to impregnate a porous workpiece arranged in the injection mould or diecast mould with a liquid or fluid impregnating agent. It has been found that with relatively short treatment times of the order of magnitude of about 1-3 minutes a substantially complete filling of the pores of the porous workpiece can be achieved. It has further been found that when using a mould having a mould cavity adapted to the shape of the workpiece and enclosing the workpiece substantially clearance-free, substantially no excess impregnating agent remains on the surface of the workpiece, making subsequent cleaning either superfluous or substantially simpler.
In a preferred method according to the invention, the cold or preheated workpiece is placed into a mould cavity of a divided, tightly closable die tool (clamping unit) of an injection moulding or diecasting machine. The clamping or closing unit is closed and the impregnating agent (liquid or brought to liquefaction temperature) is injected into the closed mould under pressure by means of the injection or diecasting unit of the machine. The mould is subjected to the pressurised liquid impregnating agent until the pores of the workpiece are completely filled, the period necessary to do this being selected based on experience.
Depending on the nature of the impregnating agent used the workpiece remains in the mould until for example the molten metal has solidified or the resin has partially or completely cured. On completion of the impregnating process, the mould is opened and the impregnated workpiece ejected by means of an ejector, after which a new cycle can begin.
By making the mould cavity an exact fit corresponding to the shaping of the workpiece, the workpiece is enclosed substantially free of clearance on all sides by the mould cavity. The gap between the workpiece and the inside surface of the mould cavity is preferably less than 100 xcexcm and more preferably smaller than the pore size of the workpiece. It can thus be ensured that the impregnating agent injected into the mould cavity flows only into the pores and not into a gap between the workpiece and the mould cavity. Consequently, the surface of the workpiece, except for the sprue (injection) point, is not contaminated with impregnating agent. This minimises the subsequent treatment of the workpiece to the breaking off and possible grinding of the sprue.
An impregnating method according to the invention can also be carried out using a diecasting machine configured for so-called squeeze casting, or using an injection moulding machine adapted for carrying out compression moulding or injection stamping. Squeeze casting or injection stamping are terms denoting methods in which at the start of the casting or injection process the two halves of a diecasting mould or injection mould are not pressed against each other with the full clamping force. Although in this state the mould cavity is already sealed, it still has a certain excess dimension compared with the dimensions when the mould halves are completely pressed against each other. The mould halves can move apart slightly under the pressure of the injected melt. The complete pressing together of the mould halves takes place after completion of the casting or injection operation.
When the impregnating method according to the invention is carried out on a diecasting or injection moulding machine configured for this procedure, there is advantageously still a small gap present between the wall of the mould cavity and the inserted workpiece at the start of the casting or injecting operation. This gap permits the liquid impregnating agent to spread uniformly over the surface of the workpiece. On final clamping of the mould halves this gap disappears and the liquid impregnating agent is mechanically forced into the pores of the workpiece.
With the method according to the invention the cycle time is substantially reduced when compared with conventional impregnating methods. Both the actual impregnating operation and the pretreatment (insertion of the workpiece into the mould cavity and closing the mould) as well as the subsequent treatment (opening the mould, removing the workpiece and if necessary removing the sprue) can be carried out in a very short time. A cycle time of 3 minutes can be achieved, for example, compared with the conventional method in which for each of the three phases requires about 1 to 4 hours.
According to another aspect of the invention, a method of impregnating can easily be automated. Depending on the nature of the workpiece, a multiple die with several mould cavities may also be employed, thereby again considerably reducing the processing time. Fundamentally, the method can be carried out with commercially available injection moulding or diecasting machines as generally employed for the injection moulding of plastics and the diecasting of metals.
A further advantage of the method according to the invention resides in that many impregnating agents, such as waxes, resins and the like, which in the prior art could only be used in the form of a solution with a solvent, can be employed free of solvent. This makes it possible to carry out the method according to the invention in a manner substantially more compatible with the environment than prior art impregnating methods. Additionally, workpieces having very different porosities can be impregnated, for example porosities in the range of from 2% to 90%.
The method is preferably employed for workpieces of carbon which are to be used as sliding bearings or electrical sliding contacts in the form of carbon brushes or collectors. Preferably, the carbon bodies are made by mixing one or more of the components natural graphite, electrographite, pyrographite, carbon fibre, coke and carbon black with a binder such as coal or petroleum tars and pitches as well as resins. The workpieces are subsequently shaped by means of pressing, ramming or extruding. Usually, the workpieces are subjected to a multistage temperature treatment taking place at between 100xc2x0 C. and 3200xc2x0 C. (for sintering, hardening, carbonising or graphitisation). The workpiece can also be made by preforming carbon fibre strands, mats, fabrics or knitted products, possibly including binding, as necessary for dimensional stability, with coal or petroleum tars or pitches or plastic resin, and subsequent temperature treatment between 100xc2x0 C. and 3200xc2x0 C.
The impregnating agents that can be used include:
natural or synthetic oils, fats, greases or waxes;
natural or synthetic resins, including synthetic resins made by modifying natural resins, such as by esterification or saponification;
plastics which have been made by polymerisation, polyaddition or polycondensation and can be brought into the flowable state necessary for impregnation;
all metals or metal alloys;
pretreated or untreated pitches.
The impregnating agent can be supplied to the closed mould containing the workpiece at one supply point or at several supply points. Mouldings which have been made for example from a pulverulent carbon material by compression or extrusion and subsequent sintering frequently have a preferred direction of the porous structure, the preferred direction lying perpendicular to the pressing direction or parallel to the extrusion direction. With such workpieces, it may be preferred to arrange the supply point of the impregnating agent on the mould in such a manner that the propagation direction of the impregnating agent in the mould cavity or through the bores of the workpiece extends substantially parallel to the preferred direction.
However, it has been found that this is not necessary as a rule. With workpieces having an anisotropic or preferred direction of the porosity the impregnating agent can be supplied at any point of the workpiece and the movement of the impregnating agent in the workpiece will take place in any direction relatively to the preferred direction. The resulting impregnation is just as uniform and homogeneous as with isostatically compressed mouldings not having any preferred direction.
An object of the present invention is to provide a new and improved method of impregnating porous workpieces.
Another object of the present invention is to provide a new and improved method of impregnating porous workpieces that requires a short treatment time to produce a very homogeneous and complete pore filling.
A further object of the present invention is to provide a new and improved method of impregnating porous workpieces which substantially eliminates the need for mechanical and/or chemical cleaning steps following impregnation.
These and other objects, features and advantages of the invention will become readily apparent to those skilled in the art upon reading the description of the preferred embodiments, in conjunction with the accompanying drawings. | {
"pile_set_name": "USPTO Backgrounds"
} |
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