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This invention relates to a system including a variable rate modulator for (1) varying the rate at which signals are modulated in accordance with variations in the rate of introduction of digital data to the system and (2) for processing the modulated signals to provide output signals at a fixed sampling frequency.
In recent years, a number of different applications have arisen in which digital signals representing data are processed and the processed signals are then converted to analog signals. For example, such applications have included the transmission of television signals through coaxial lines to homes. In such systems, the digital data is converted to analog signals and the analog signals are then transmitted through coaxial lines to homes of subscribers. Other applications are in microwave links and satellite communications.
In a number of the different applications involving the processing of digital data and the conversion of the processed digital data to analog signals, the digital data is provided at a variable input frequency or rate and the analog signals are provided at a fixed sampling frequency different from the variable input frequency or rate. For example, the digital data may be provided in the range of approximately 0.1-20 megabits per second and the analog signals may be sampled at a fixed frequency in the range of approximately 100-200 megahertz.
In the above example, the variable rate digital signals in the range of 0.1-20 megabits/second are converted to a modulated analog intermediate frequency signal having a fixed sampling frequency. For example, the digital signals in the range of 0.1-20 megabits/second may be converted to signals at a fixed sampling frequency of approximately 100-200 megahertz. The signals at the sampling frequency are then modulated onto a programmable carrier frequency in the range of approximately 5-65 MHz. at the fixed sampling frequency of approximately 100-200 megahertz.
As will be seen from the above discussion, a considerable range of frequencies (e.g. 0.1-20 megabits/second) have to be converted to a single fixed frequency (e.g. 120 megahertz). This is not easy. If the conversion is not accurate, the signals at the fixed sampling frequency jitter. When the signals illustratively provide television information, the jitter produces a significant deterioration in the quality of the television image.
This invention provides a system for, and method of, converting digital data signals variable through a wide range of frequencies or rates into signals at a fixed sampling frequency. This conversion occurs without any jitter in the signals at the fixed sampling frequency. When the system of this invention is illustratively used to provide television images, the television images have a high resolution.
In one embodiment of the invention, digital data signals at a variable input frequency are converted by a numerically controlled oscillator and an interpolator to a signal at a fixed sampling frequency. The conversion of the variable input frequency to the fixed output sampling frequency may be by a factor other than an integer.
The interpolated digital data signals at the output sampling frequency are then modulated onto a pair of trigonometric signals at a programmable carrier frequency, one signal having a cosine function and the other signal having a sine function.
The modulated pair of trigonometrically related signals at the fixed sampling frequency are then combined to create a modulated signal at a carrier frequency determined by the frequency of the sine and cosine signals. The modulated signal is sampled at the fixed sampling frequency and converted to a corresponding analog signal using a digital-to-analog converter. | {
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This invention relates to measurement of uterine contrations or other biological phenomena involving displacement of an external body surface.
A tocodynamometer for making such measurements typically involves a movable patient contacting member and a transducer for converting displacement into an electrical output. | {
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The present invention relates to ultrasonic flow metering. Ultrasonic flow metering, or the determination, using ultrasonic energy, of flow velocity through a conduit, such as a pipeline, is based on determining the effect of fluid flow on the upstream versus downstream transmission time of an ultrasonic signal passing diagonally through the fluid in the pipeline. Ultrasonic flow metering is particularly advantageous because it can be performed non-intrusively, i.e., without requiring intrusion into the pipeline. The ultrasonic flow meter transmitting and receiving transducers are suitably clamped on to the pipeline and ultrasonic signals are injected through the pipewall. The flow rate is determined by measuring the difference in transit time between upstream and downstream ultrasonic signals. Since the effect of flow on transit-time, even at high flow velocities, is small, it is essential to avoid even small uncertainties in this measurement. Unfortunately, the ultrasonic signal which is used for detection is of low resolution relative to the needed time detection resolution, since it generally consists of waves of periods of from hundreds to thousands of nanoseconds, while the needed detection resolution is of the order of from picoseconds to only a few nanoseconds at best.
In addition, to detect the arrival time of the sonic signal implies that there is a detectable "beginning" of the signal. Unfortunately, the signal does not arrive with a sharp front edge, but rather is a relatively slow buildup of a basically sinusoidal waveshape, due to the high "Q" of the ultrasonic transmitter, as well as the sonic resonance of the pipe wall or other structure through which the wave must pass in order to enter the liquid stream. These metallic structures are generally highly resonant, and contribute to the slow buildup of the waveshape. Thus at best, the beginning of the signal is hard to detect, and an error in detecting the arrival by even only one cycle of the receive signal frequency has a disastrous effect on the measured flow due to this effect on the apparent upstream versus downstream detection time difference.
Furthermore, even if the first arrival cycle is robust, it must be recognized that there is a background level of noise, much of it at the frequency of the receive signal itself, and therefore unfilterable. Accordingly, in present systems, detection of the actual arrival time of the beginning of the receive signal is either very difficult, uncertain as to its arrival time, or simply impossible in any real way, depending on the actual character of the signal and the ambient noise present when it arrives. | {
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The present invention relates to computer-aided design (CAD) tools for analyzing integrated circuits and, more particularly, to analyzing power Vdd and ground nets in integrated circuits for electromigration, voltage drop and ground bounce.
Aggressive development within the semiconductor industry keeps electronic products moving on a brisk course forward. With each new generation of integrated circuit (IC) chips, device geometries and supply voltages are decreasing while the clock frequencies are increasing. Typical ICs today contain more than three million transistors and include three to five layers of metal interconnects that supply power and transport signals.
Along with smaller device geometries come narrower metal lines and larger resistances. Also, as more devices are interconnected, the lines are getting longer, further increasing the interconnect resistance. The substantial voltage drops that develop across metal power nets cause the circuits to malfunction, especially when the supply voltage is reduced below 3 volts. For example, a 1 volt drop in a 3 volt system would have a much more severe impact on circuit functionality than a proportional drop in a 5 volt system. So, in deep submicrometer designs (feature sizes less than 0.5 .mu.M), voltage drop analysis is crucial. Additionally, the narrower metal lines have undesirable wear-out of metal wiring caused by electromigration.
Ground bounce is due to the inductance in the IC package pins and bonding wires and the current switching (dI/dt) in the integrated circuit. Ground bounce noise may affect circuits in various ways. For example, ground bounce noise may degrade the performance of the circuit. Additionally, ground bounce noise may cause the circuit to malfunction due false latching in receiving chips.
In deep submicron design, the circuit consumes more power which means that dI/dt is even greater than in nonsubmicron designs. The ground bounce problem in the past was more significant in output buffers than on-chip circuits. However, the ground bounce noise in on-chip circuits is becoming more important with today's technologies.
Numerous CAD tools exist for simulating transistor networks of ICs (e.g., SPICE). An innovative system is described in U.S. patent application Ser. No. 08/040,531, entitled "Transistor-Level Timing and Power Simulator and Power Analyzer", filed Mar. 29, 1993 by Huang et al., and U.S. patent application Ser. No. 08/231,207, entitled "Power Diagnosis for VLSI Designs", filed Apr. 21, 1994 by An-Chang Deng, which are both hereby incorporated by reference for all purposes. However, none of the prior art systems allow the user to simulate the power nets of an IC and display power net characteristics like voltage drop, current density and ground bounce. The present invention fulfills this and other needs. | {
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In gas turbines, during operation, heavy thermo acoustic (i.e. pressure) pulsations can occur in the combustion chamber, because of an incorrect combustion of the fuel (such as gas or oil).
These pulsations subject the hardware of the combustion device and the turbine to heavy mechanical vibrations that can result in the damage of individual parts of the combustion device or turbine.
In order to absorb such pulsations, combustion devices are usually provided with dampers, such as the Helmholtz dampers.
Helmholtz dampers consist of a resonance chamber that is connected via a damping tube to the interior of the combustion chamber (or the medium surrounding the combustion chamber).
When the volume of the chamber, the length of the tube and the area of the tube are in a defined ratio with each other, such a system is able to damp acoustic pulsations (i.e. pressure pulsations) in a certain frequency band.
Usual reheat combustion devices have one Helmholtz damper with the tube connected to the inner of the combustion chamber.
Nevertheless, as these systems only have one single Helmholtz damper for each device (therefore the damping area, corresponding to the cross section of the tube, is very small when compared with the total area of the device exposed to acoustic pulsations), their damping effect is very poor.
US2005/0229581 describes a reheat combustion device that has a mixing tube followed by a combustion chamber; the mixing tube has at its front panel an acoustic screen provided with holes and, parallel to it, an impingement plate also provided with holes.
The acoustic screen and the impingement plate define a chamber connected to the inner of the combustion chamber (via the holes of the acoustic screen) and to the outer of the combustion chamber (via the holes of the impingement plate).
During operation, air (from the compressor) passes through the holes of the impingement plate, impinges on the acoustic screen and then enters the combustion chamber; this lets the acoustic screen and the impingement plate be cooled.
Moreover, the chamber between the impingement plate and acoustic screen defines a plurality of Helmholtz dampers such that, since a plurality of dampers are associated to each reheat combustion device, the damping effect is improved.
Nevertheless, also this damping system has a plurality of drawbacks.
In fact, during operation hot gases may enter from the combustion chamber into the chamber between the impingement plate and the acoustic screen and go out again, coming back into the combustion chamber.
Usually when this occurs, the hot gases recirculate passing through two adjacent holes of the acoustic screen; this phenomenon is known as ingestion.
If ingestion occurs, the hot air flow that recirculates makes the acoustic screen and impingement plate burn in a very short time.
This could be prevented by increasing the air entering from the outside into the chamber between the impingement plate and acoustic screen through the holes of the impingement plate, but this would cause the air within the combustion chamber, that does not take part in the combustion, be increased and, consequently, the NOx emissions be increased.
A further drawback of ingestion is that of detuning of the acoustic damper.
In fact, as the temperature increases in case of hot gas ingestion, the speed of sound also increases in the damping device and, for a given geometry, the range of efficient damping is shifted off the target pulsation frequency. This makes the damper acoustically inefficient.
Moreover, as the air flow within the chamber between the impingement plate and the acoustic screen is not guided, the cooling efficiency is not optimised; this makes different parts of the combustion chamber to be cooled in different way and to operate at different temperatures.
In addition, manufacturing is very hard. | {
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There are some applications that are designed to assist people in scheduling appointments, meetings and social events, such as birthday parties, etc.
For example, a calendar application running on a personal digital assistant (PDA) may allow a user to schedule an appointment on the calendar presented on the PDA device. The user may type in a description of the location of the appointment, a subject for the appointment, and a note for the appointment. The user may specify the starting time and the ending time of the appointment, and select an option to receive, from the PDA device, an alert about the appointment prior the appointment.
Some calendar applications allow the user to invite participants. For example, the user may select email addresses from a list as invitees of a meeting and type in a description about the location of the meeting and type in a separate message about the meeting. An email program integrated with the calendar application then sends email invitations to the invitees.
There are web based services that allow a user to compose a message and to invite participants to an event. A web-based user interface allows the user to type in a description of the location of the event, the email addresses of the invitee, and an invitation message. The web-based application then sends email invitations to the invitees based on the information received from the web-based user interface. | {
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Applicators for applying various materials to a substrate, such as liquid coatings, solvents, adhesives, or other materials, are well known, including applicators which are incorporated into the cover or lid of a jar or other container, as the applicator brush incorporated into the lid of a glue or rubber cement jar. Such applicators, however, are limited in their use, as the glue brush usually doesn't quite reach the bottom of the container, and the lid to which it is attached fits only on a single diameter container opening, and does not fit onto a container with a different diameter opening. Also, when a separate applicator is used to apply a coating, it must be cleaned after use and stored separately from the container, which leads to the applicator becoming grimy or gritty before a subsequent use. It is also possible that the applicator can become separated from the container, misplaced or lost, which requires the operator additional time to locate it. Coatings commonly are packaged in cans, normally one quart or one gallon, or similar variations. Such cans are provided with an opening, neck, or spout. It is desirable that a lid be provided to a manufacturer that can be used on the two most popular sizes of cans, and that are interchangeable between the can spout diameters of such cans. Thus, there is a need for an applicator that can be extended to reach the lowermost portion of a container, that is integral with the container lid, and will fit more than one diameter of container opening. | {
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1. Field of the Invention The present invention relates to an alternator driven by an internal combustion engine, for example, and in particular, relates to a stator construction for an automotive alternator mounted to an automotive vehicle such as a passenger car or a truck.
2. Description of the Related Art
In recent years, compact high output and improvements in quality have been increasingly required of alternators. In order to achieve compact high output, it is important to design constructions which distribute magnetic loading and electrical loading in the most appropriate manner, and with the highest possible density within a limited volume.
For example, as engine compartments become progressively smaller, mounting space for automotive alternators is becoming less and less free, but at the same time, improvements in alternator output are required because of increases in automotive vehicle loads. Furthermore, there is increased need for noise reduction both inside and outside automotive vehicles, and although engine noise has been reduced, noise from automotive alternators, which run constantly to generate electricity in order to supply the electrical load for the vehicle, has remained a problem. Fan noise and magnetic noise in particular have been problems in automotive alternators which operate in a wide range of rotational frequencies from low to high speed.
Because automotive alternators are constantly generating electricity, they generate a lot of heat due to the joule heat of the output electric current and are subjected to a severe heat environment, requiring extremely high heat resistance.
Furthermore, within the engine compartment, an automotive alternator is often mounted directly onto an engine, where it is exposed to liquids such as engine oil and antifreeze, in addition to rain water, salt water, mud, etc., conditions where the corrosive environment is extremely severe. There are problems due to corrosion which lead to interruptions in power generation, etc., but most causes of interruption to power generation are the result of damage to insulation on a winding which occurs during the process of manufacturing a stator, or due to electrical short-circuiting in structurally exposed portions of the winding.
For compact high output by alternators, in particular, it is necessary to increase the space factor of electrical conductors housed within magnetic circuits of the stator, and to line up and increase the density of bridge portions of the stator winding (bridge portions outside a stator core are called coil ends), and in addition to this, various improvements have been proposed in order to answer the requirements for low noise, heat-resistance, corrosion resistance, etc., mentioned above. Constructions aimed at increasing the space factor of the electrical conductors using short conductor segments for the electrical conductors in the stator or aimed at lining up and increasing the density of the coil ends have been proposed in the publication of WO 92/06527 and in Japanese Patent No. 2927288, for example.
FIG. 37 is a side elevation showing part of a stator of a conventional automotive alternator such as described in Japanese Patent No. 2927288, for example, FIG. 38 is a perspective showing a conductor segment used in the stator of the conventional automotive alternator shown in FIG. 37, and FIGS. 39 and 40 are perspectives from a front end and a rear end, respectively, of part of the stator of the conventional automotive alternator shown in FIG. 37.
In FIGS. 37 to 40, the stator 50 includes: a stator core 51; a stator winding 52 wound onto the stator core 51; and insulators 53 mounted inside slots 5a, the insulators 53 insulating the stator winding 52 from the stator core 51. The stator core 51 is a cylindrical laminated core laminated by stacking thin steel plates, and has a number of slots 51a extending axially disposed at even pitch circumferentially so as to be open on an inner circumferential side. In this case, ninety-six slots 51a are formed so as to house two sets of three-phase winding portions such that the number of slots housing each phase of the winding portions corresponds to the number of magnetic poles (sixteen) in a rotor (not shown). The stator winding 52 is constructed by joining a number of short conductor segments 54 in a predetermined winding pattern.
The conductor segments 54 are formed into a general U shape from an insulated copper wire material having a rectangular cross section, and are inserted two at a time from an axial rear end into pairs of slots 51a six slots apart (a pitch of one magnetic pole). Then, end portions of the conductor segments 54 extending outwards at a front end are joined to each other to constitute the stator winding 52.
More specifically, in pairs of slots 15a six slots apart, first conductor segments 54 are inserted from the rear end into first positions from an outer circumferential side within first slots 51a and into second positions from the outer circumferential side within second slots 51a, and second conductor segments 54 are inserted from the rear end into third positions from the outer circumferential side within the first slots 51a and into fourth positions from the outer circumferential side within the second slots 51a. Thus, within each slot 15a, four straight portions 54a of the conductor segments 54 are arranged to line up in a row in a radial direction.
Then, end portions 54b of the conductor segments 54 extending outwards at the front end from the first positions from the outer circumferential side within the first slots 51a and end portions 54b of the conductor segments 54 extending outwards at the front end from the second positions from the outer circumferential side within the second slots 51a six slots away in a clockwise direction from the first slots 51a are joined to form an outer layer winding having two turns. In addition, end portions 54b of the conductor segments 54 extending outwards at the front end from the third positions from the outer circumferential side within the first slots 51a and end portions 54b of the conductor segments 54 extending outwards at the front end from the fourth positions from the outer circumferential side within the second slots 51a six slots away in a clockwise direction from the first slots 51a are joined to form an inner layer winding having two turns.
In addition, the inner layer winding and outer layer winding constituted by the conductor segments 54 inserted into the pairs of slots 51a six slots apart are connected in series to form one phase of the stator winding 52 having four turns.
A total of six phases of the stator winding 52 each having four turns are formed in this manner. Then, two sets of three-phase stator winding portions are constructed by connecting three phases each of the stator winding 52 into alternating current connections.
In the conventional stator 50 constructed in this manner, at the rear end of the stator core 51, turn portions 54c of the pairs of conductor segments 54 inserted into the same pairs of slots 15a are lined up in rows in a radial direction. As a result, the turn portions 54c are arranged in two rows circumferentially to constitute a rear-end coil end group.
At the front end of the stator core 51, on the other hand, joint portions formed by joining the end portions 54b of the conductor segments 54 extending outwards at the front end from the first positions from the outer circumferential side within the first slots 51a and the end portions 54b of the conductor segments 54 extending outwards at the front end from the second positions from the outer circumferential side within the second slots 51a six slots away, and joint portions formed by joining the end portions 54b of the conductor segments 54 extending outwards at the front end from the third positions from the outer circumferential side within the first slots 51a and the end portions 54b of the conductor segments 54 extending outwards at the front end from the fourth positions from the outer circumferential side within the second slots 51a six slots away are arranged to line up radially. As a result, joint portions formed by joining end portions 54b to each other are arranged in two rows circumferentially to constitute a front-end coil end group.
In the stator 50 of the conventional automotive alternator, as explained above, the stator winding 52 is constructed by inserting short conductor segments 54 formed in the general U shape into the slots 51a of the stator core 51 from the rear end, and joining end portions 54b of the conductor segments 54 extending outwards at the front end.
Thus, because the front-end coil end group is constructed by circumferentially arranging the joint portions formed by joining the end portions 54b, which have lost their insulation due to soldering or welding, the coil-end construction is easily corroded by exposure to moisture, making corrosion resistance extremely low.
Furthermore, because the front-end coil end group is composed of two rows of ninety-six joint portions, i.e., 192 joint portions, the construction facilitates short-circuiting between the joint portions, increasing the likelihood of short-circuiting accidents.
A large number of the short conductor segments 54 must be inserted into the stator core 51 and their end portions 54b must be joined by welding, soldering, etc., significantly reducing operability. Furthermore, the amount of each conductor segment 54 which is inserted into the slots 51a must be greater than the length of the stator core 51, facilitating damage to the insulation and reducing the quality of the finished product. In addition, when joining the end portions 54b, short-circuiting often occurs between the joint portions due to spilt solder or weld melt, significantly decreasing mass-producibility.
The end portions 54b of the conductor segments 54 are joined to each other by clamping a portion thereof in a jig, and soldering or welding the tips thereof. Thus, because clamping area is required for the jig and expansion of the soldered portions or welded portions occurs, the height of the coil ends is increased and space between the joint portions is reduced. As a result, coil leakage reactance in the coil end portions is increased, causing output to deteriorate, and wind resistance is increased, exacerbating wind noise.
Furthermore, as a measure against magnetic noise, mutual cancellation of magnetic pulsation forces by winding two sets of three-phase windings into slots in positions offset by an electrical phase difference of 30xc2x0 has been proposed in Japanese Patent Laid-Open No. HEI 4-26345, for example. However, when attempts are made to adopt this example of improvement of magnetic noise in small stators, the slot spacing becomes extremely narrow because twice as many slots are required. Thus, it was not possible to apply general winding methods in which a stator winding is constructed by preparing an annular coil by winding continuous wire into an annular shape, then, preparing a star coil by deforming this annular coil into a star shape, then installing straight portions of the star coil into the slots of the stator core. Furthermore, the above-mentioned winding method using the conductor segments 54 could not be applied because buckling, etc., of the conductor segments 54 occurs during insertion into the slots. Additionally, when welding the end portions 54b of the conductor segments 54 to each other, the conductor segments 54 are softened by temperature increases during welding, reducing the rigidity of the stator and decreasing the effective reduction in magnetic noise.
In addition, it is necessary to answer the various demands of automotive alternator output with electromagnetic design. In particular, in order to improve output of an alternator in a low-speed frequency region in response to idling frequency in an automotive engine, it is necessary to shift an output commencement frequency to the low-speed side. To this end, it is necessary to improve the voltage induced by the alternator by increasing magnetomotive force, that is, electric current supplied to a field coil, or by increasing the total conductor count, that is, the number of turns in the stator. Now, with the former, the output commencement frequency can be shifted to the low-speed side by increasing the supply of electric current to the field coil, but this is limited by reductions in the saturation of the magnetic circuits. With the latter, the output commencement frequency can be shifted to the low-speed side by increasing the number of turns, but when attempts are made to increase the total conductor count in a winding based on conductor segments 54, the number of joint portions increases proportionately, leaving no space for joining, and excessive increases in the number of turns cannot be practically applied.
The present invention aims to solve the above problems with the conventional art and an object of the present invention is to provide an alternator having both high serviceability and productivity, capable of satisfying the performance and quality commonly required of today""s alternators.
An additional object of the present invention is to provide an alternator applicable to automotive use which has compactness, high output, and low noise.
In order to achieve the above object, according to one aspect of the present invention, there is provided an alternator comprising:
a rotor for forming north-seeking (N) and south-seeking (S) poles about a rotational circumference;
a stator comprising:
a stator core disposed facing the rotor; and
a polyphase stator winding installed in the stator core; and
a bracket supporting the rotor and the stator,
wherein the stator core comprises a laminated iron core formed with a number of slots extending axially at a predetermined pitch in a circumferential direction,
the polyphase stator winding comprises a number of winding subportions in each which a long strand of wire is wound so as to alternately occupy an inner layer and an outer layer in a slot depth direction within the slots at intervals of a predetermined number of slots, the strand of wire folding back outside the slots at axial end surfaces of the stator core to form turn portions,
the turn portions align in a circumferential direction to constitute coil end groups at both axial end portions of the stator core, and
the turn portions constituting the coil end groups at both axial end portions of the stator core are formed in the generally identical shape in a circumferential direction. | {
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In recent years, an automobile requires various information such as a load acting on a vehicle wheel or a rotation speed of the vehicle wheel in order to carry out a driving control in a traveling mode. In order to obtain such information, there is proposed a technique in which a sensor is provided in a vehicle-wheel rolling bearing attached with a vehicle wheel of an automobile.
As the known vehicle-wheel rolling bearing, there is a bearing including a cylindrical fixed ring which is fixed to a vehicle body; a rotary ring which is provided in the fixed ring in an inner radial direction so as to attach a vehicle wheel thereto; and plural rows of rolling elements which are provided between the fixed ring and the rotary ring so as to roll. In the bearing, the above-described sensor is provided in the fixed ring, and the information of the rotary ring is obtained from the sensor.
In the bearing, a through hole is formed through the fixed ring in a radial direction, and the sensor is inserted into the through hole. In addition, a measurement portion of the sensor is opposed to the outer peripheral surface of the rotary ring so that the sensor acquires the information of the rotary ring.
However, in the vehicle-wheel rolling bearing, it is necessary to form plural through holes in the fixed ring in order to provide plural sensors in the fixed ring. In this case, another penetration process is required in the manufacture process of the fixed ring, and the through holes are respectively required to be equipped with the sensors, thereby complicating the assembling process. In addition, it is necessary to adjust a gap between the sensor and the rotary ring in every sensor. As a result, a problem arises in that the number of assembling processes increases. | {
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The present invention, in some embodiments thereof, relates to closures, and more particularly but not exclusively to closures for items such as jewelry, especially rings, bracelets and earrings and including Huggie earrings.
Rings with closures are useful in the case of fingers whose sizes change over the course of a lifetime, not an uncommon phenomenon. As well as change in size, arthritic joints can make it painful to allow closely fitting rings or bracelets to slide over.
Huggie earrings are a popular style of earring and are so-called because the setting hugs the earlobe. Many custom jewelers make huggie earrings because of the many varieties of setting that can be used. For example, stones may be channel set in huggie earrings. Settings for huggie earrings may come in different shapes and sizes, including hearts, rectangles, ring shapes and horseshoes.
Huggie earrings generally have closure mechanisms which provide an open position in which the pin is exposed for insertion or removal from the piercing, and a closed position for holding the earring in position once inserted.
FIG. 1A shows a basic ring-shaped huggie earring in profile and seen side on. The setting is hinged so that the earring can be opened. The earring is then inserted into the piercing and may then be closed to hold the earring securely in place. A catch holds the hinged part in position in the closed position and may be released in order to open the earring.
FIG. 1B shows a profile and perspective view of a huggie earring with five rows of gemstones in the setting, placed using an invisible setting technique.
FIG. 1C shows a profile and side-on view of another huggie earring with gemstones set in two rows using an invisible setting technique.
The closure mechanism in each case consists of a sprung catch with a release mechanism. The catch and release mechanism consists of several moving parts, each of which can be a separate cause of failure so that each moving part reduces the overall life expectancy of the product. In addition the catch and release mechanism is intrinsically awkward to use since it must be operated whilst on the ear of the wearer, a position which the wearer is unable to see so must work on touch alone. | {
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The present invention relates to a catalyst having a porous support, buffer layer and interfacial layer; methods of making the catalyst; and catalytic processes utilizing the catalyst.
Hydrogen and hydrocarbon conversion reactions including such as steam reforming, water-gas shift reactions, methanol synthesis and catalytic combustion are well known. These reactions are usually carried out at temperatures between 150 and 1000xc2x0 C. Currently these reactions are industrially run using catalyst pellets which consist of an active catalytic metal or metal oxide deposited on high surface area ceramic pellets.
Foam or monolith catalysts are known that have three layers (1) porous support, (2) interfacial layer, and (3) catalyst metal as described in [1]. In making these catalysts, the interfacial layer has been deposited by various methods including solution impregnation techniques. The catalyst layer may be deposited by solution impregnation techniques. The interfacial layer has greater surface area than the porous support whereas the porous support has greater mechanical strength than the interfacial layer.
The porous support may be a metal or ceramic foam. Metal foams are highly thermally conductive and easy to machine. The sponge-like mechanical properties allow convenient sealing in a reaction chamber via mechanical contact. The closely matched thermal expansion between the metal foam and the housing reaction chamber minimizes cracking of the porous support and minimizes gas channeling around the porous support at higher reaction temperatures. Pestryakov et al prepared metal foam supported transition metal oxide catalysts with [1] and without [2] an intermediate gamma-alumina layer for the oxidation of n-butane. Kosak [3] examined several approaches to disperse precious metals on various metal foams where the surface was pre-etched with HCl solution, and reported that electroless deposition provides the best adhesion of precious metals to the foam supports. Podyacheva et al. [4] also synthesized foam metal supported LaCoO3 perovskite catalyst with a porous alumina intermediate for methane oxidation. Despite all of the potential advantages with metal foam supported catalysts, metal foam has low corrosion resistance and its nonporous and smooth web surfaces have provided poor adhesion to ceramic materials, and these materials are prone to spalling of interfacial layers after thermal cycling because of the mismatch in thermal expansion.
In order to increase corrosion resistance, methods such as diffusion alloying with Al, Cr, and Si have been used to fabricate ferritic steels, which are typically used for the manufacturing of high temperature furnace elements (about 1200xc2x0 C.) [5]. When the aluminum containing ferritic steels are appropriately heat-treated, aluminum migrates to the alloy surface and forms a strongly adhering oxide film which is resistant to oxygen diffusion. Such ferritic steel foils have been used to fabricate metal monoliths with greater than 10 ppi (pores per inch) open cells [6]. However, the search for the similar alloy foams with pores suitable for catalytic applications ( less than 20 ppi, 80 ppi preferred) has been fruitless. This has been attributed to both the immature methods for making the finer Al-ferritic steel foams and the lack of the alloy precursors for making the foams.
Hence, there is a need in the art of supported catalysts for a porous support of a foam that is resistant to corrosion or oxidation and resists cracking of the interfacial layer.
References
1. A. N. Pestryakov, A. A. Fyodorov, V. A. Shurov, M. S. Gaisinovich, and I. V. Fyodorova, React. Kinet.Catal.Lett., 53 [2] 347-352 (1994).
2. A. N. Pestryakov, A. A. Fyodorov, M. S. Gaisinovich, V. P. Shurov, I. V. Fyodorova, and T. A. Gubaykulina, React.Kinet.Catal. Lett., 54 [1] 167-172 (1995).
3. J. R. Kosak. A Novel Fixed Bed Catalyst for the Direct Combination of H2 and O2 to H2O2, M. G.Scaros and M. L.Prunier, Eds., Catalysis of Organic Reactions, Marcel Dekker, Inc. (1995), p115-124.
4. O. Y. Podyacheva, A. A. Ketov, Z. R. Ismagilov, V. A. Ushakov, A.Bos and H. J.Veringa, React.Kinet.Catal.Lett., 60 [2] 243-250 (1997).
5. A. N. Leonov, O. L. Smorygo, and V. K. Sheleg, React.Kinet.Catal.Lett., 60 [2] 259-267 (1997).
6. M. V. Twigg and D. E. Webster. Metal and Coated-Metal Catalysts, A Cybulski and J. A. Moulijn, Eds., Structured Catalysts and Reactors, Marcel Dekker, Inc. (1998), p59-90.
The present invention includes a catalyst that has at least three layers, (1) porous support, (2) buffer layer, (3) interfacial layer, and optionally (4) a catalytically active layer. In some embodiments, the buffer layer, which is disposed between the porous support and the interfacial layer, contains at least two compositionally different sublayers. The buffer layer typically provides a transition of thermal expansion coefficient from the porous support to the interfacial layer thereby reducing thermal expansion stress as the catalyst is heated to and cooled from high operating temperatures. The buffer layer also reduces corrosion and oxidation of the porous support, and minimizes side reactions catalyzed by the surface of the porous support.
The invention also provides a catalyst having a porous support, a buffer layer disposed between the porous support and an interfacial layer; and wherein the catalyst possesses oxidation resistance such that, if it is heated at 580xc2x0 C. in air for 2500 minutes the catalyst increases in weight by less than 5%. Alternatively, the catalyst may also be characterized by its resistance to flaking during thermal cycling.
The invention further provides a process of converting at least one reactant to at least one product in which the reactant is passed through a reaction chamber containing the catalyst.
The method of the present invention for making the multi-layer catalyst (at least three layers) has the steps of (1) selecting a porous support, (2) depositing a buffer layer on the porous support, (3) depositing an interfacial layer thereon, and optionally (4) depositing a catalytically active layer onto or integral with the interfacial layer; wherein the buffer layer is disposed between the porous support and the interfacial layer. Better results can be obtained where the buffer layer is vapor deposited. The catalytically active layer can be deposited after or during the deposition of the interfacial layer.
Advantages of the present invention, that include a porous support with a buffer layer and an interfacial layer, may include: better match of thermal expansion coefficients and better stability to temperature changes, reduction of side reactions such as coking, desired metal-oxide interactions, strong bonding to a high-surface-area interfacial layer, and enhanced protection of the underlying porous support.
The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation, together with further advantages and objects thereof, may best be understood by reference to the following description taken in connection with accompanying drawings wherein like reference characters refer to like elements. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to an image heating apparatus for heating an image on a recording material. As such image heating apparatus, mention can be made, for example, a fixing apparatus for fixing an unfixed image on a recording material, a gloss improving apparatus or the like for heating an image fixed on a recording material to thereby improve the gloss of the image. Also, such an image heating apparatus is used, in an image forming apparatus such as, for example, a copying machine, a printer, a facsimile apparatus or a compound machine provided with a plurality of functions of these.
2. Description of the Related Art
Heretofore, in an image forming apparatus of an electrophotographic printing method, a technique of forming a toner image on a recording material such as paper by a technique called the Carlson process, and thereafter fixing the toner image as a permanent image has been popular.
As fixing methods therefore, various methods have been proposed, but from the viewpoint of fixability, a method of heating and fixing a toner image (heat-fixing method) is popular. Above all, a method of directly bringing a toner image into contact with a rotary member containing a heating source therein to thereby fix the toner image is widely used.
In this heat-fixing method, it is important to uniformize the temperature distribution or a heating rotary member such as a roller or film, including an area through which a recording material (hereinafter referred to as the paper) passes, relative to an axial direction. For if there is a portion in which the temperature is lower than a predetermined temperature, there is the possibility of faulty fixing occurring, and on the other hand, if the temperature is too high, there is the possibility of the heating rotary member or a member proximate thereto receiving thermal damage. Further, if the temperature of a non-sheet passing portion has become too high as compared with the temperature of a sheet passing portion, the temperature of the end portion of the sheet passing portion becomes too high as compared with a proper fixing temperature, and this gives rise to the fear that hot offset should occur.
In recent years, there is a demand for an image forming apparatus which copes with various paper sizes from paper of a relatively large size such as, for example, A3 size to paper of small sizes such as A4R and B5 size usually used. Therefore, it is necessary to construct the axial lengths of the heating rotary member and a pressure rotary member so as to correspond to a relatively large size such as, for example, A3 size. However, in a case where the construction as previously described is adopted, when paper of a small size such as A4R or B5 passes through a fixing apparatus, a non-sheet passing area through which the paper does not pass increases in the effective fixing area of the heating rotary member. When copying is continuously effected on the paper of a small size, heat is not taken away from the surface of the heating rotary member corresponding to the non-sheet passing area by the paper and therefore, the surface temperature of the non-sheet passing area becomes very high.
In order to solve the above-noted temperature rise of the non-sheet passing portion, the following propositions have been made.
Conventional Example 1: the supply of heat to the heating rotary member is stopped between sheets, and idle rotation or the like is effected so that the surface temperature of the heating rotary member in the non-sheet passing area may become the same as the surface temperature of the sheet passing area to thereby cope with the problem.
Conventional Example 2: there is adopted a technique of changing the light distribution ratio of heating means such as a heater contained in the heating rotary member so that the quantity of heat supplied to the non-sheet passing area may be smaller than the quantity of heat supplied to the sheet passing area for effecting the fixing of paper of a small size.
The above-described conventional examples, however, suffer from the following problems. In Conventional Example 1 described above, during the continuous supply or the like of small size paper, idle rotation for the cooling of the heating rotary member is necessary between sheets, and this gives rise to the problem that the productivity when the paper of a small size is supplied becomes bad. In recent years, a user's requirement for the productivity of the apparatus has gradually become higher, and it may lead to the possibility of becoming unable to satisfy the product specification required by the user to lower the productivity during the mixed loading of various sizes.
Next, when a construction like Conventional Example 2 is adopted, to cope with a plurality of paper sizes, it is necessary to dispose a heater having a plurality of light distributions, and this leads to the fear of an increased cost.
Also, in order to prevent the rise of the surface temperature of the non-sheet passing area during the supply of small size paper, there has been proposed a construction for cooling the non-sheet passing area by cooling air, as described in Japanese Patent Application Laid-open No. S60-136779 and Japanese Patent Application Laid-open No. H05-181382.
In a fixing apparatus described in Japanese Patent Application Laid-open No. S60-136779, the surroundings of a pressure roll is partitioned into a sheet passing area side and a non-sheet passing area side by a partition plate, and cooling air is blown from a cooling fan disposed in the interior of the fixing apparatus to the outer peripheral member of the pressure roll on the aforementioned non-sheet passing area side.
In Embodiment 1 (FIG. 21) described in Japanese Patent Application Laid-open No. H05-181382, a cooling fan 4 is disposed above a top plate 5 covering the upper part of a fixing roll 1; and normally air is blown to the upper side of the top plate 5 to thereby prevent the temperature rise around a fixing device. When paper passing through a fixing area is small size paper, a window 6 as a guide device provided in the top plate 5 is opened to thereby let cooling air flow to the surface portion of the fixing roll 1 rotated through the non-sheet passing area.
However, the apparatuses described in Japanese Patent Application Laid-open No. S60-136779 and Japanese Patent Application Laid-open No. H05-181382 suffers from the following problems.
In the conventional examples wherein cooling air is blown to the heating rotary member, a cooling fan is provided in the interior of the fixing apparatus and therefore, it is necessary to use a cooling fan of high heat resistance, and this leads to the fear of an increased cost. Also, a cooling fan having a relatively great air flow amount becomes necessary, and the fixing apparatus itself becomes bulky. Also, there is the problem that even if a partition plate is provided, cooling air flows from the non-sheet passing area side into the sheet passing area, and the temperature is lowered near the boundary between the sheet passing area and the non-sheet passing area and the fixing temperature of the partition boundary portion becomes low to thereby cause faulty fixing.
As means for solving the above-noted problem, a fixing apparatus of the following construction has been proposed. That is, the fixing apparatus is provided with a cooling device having a non-sheet passing area cooling duct having an air blowing port formed in opposed relationship with the surface of the non-sheet passing area of a heating rotary member in order to cool the surface of the non-sheet passing area of the heating rotary member, and an air blowing fan for blowing cooling air to the duct. It has a shutter (closure plate) for adjusting an area for blowing the cooling air to the abovementioned non-sheet passing area to an optimum width in accordance with the width of small size paper. The fixing apparatus further has an opening width adjusting member for adjusting the opening width by the shutter in accordance with the width of the aforementioned small size paper.
Also, the cooling fan for blowing the aforementioned cooling air has control means for switching on and off the cooling fan at predetermined timing by the use of the result of the temperature detection of the aforementioned non-sheet passing area. Further, the shutter for adjusting the area blowing the aforementioned cooling air to an optimum opening width in accordance with the width of the small-sized sheet shields the heating rotary member and the cooling fan. Therefore, there can be provided a fixing apparatus in which the temperature of the cooling fan portion does not rise, and which can efficiently prevent temperature rise at a low cost/saved space without using a cooling fan of high heat resistance, and is also excellent in safety.
The above-described proposition, however, suffers from the following problem. In a case where a print job in which paper of a large size and paper of a small size are mixedly prevent is executed, if as shown in FIG. 22 of the accompanying drawings, the changeover operation of the position of the shutter is performed each time the paper size changes between the large size and the small size, there will arise the problem that the life of a shutter driving portion becomes short. Also, if the movement of the shutter is carried out at a high frequency, it will lead to an increase in the electric power consumption of the apparatus. | {
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1. Field of the Invention
This invention relates to an exposure time control device which is arranged to correct an exposure error resulting from overlapping of the curtains of a focal plane shutter, and the like.
2. Description of the Prior Art
Generally, exposure time control for a camera having a focal plane shutter is performed as follows: An exposure time controlling timer circuit is actuated to perform a time counting operation while a leading shutter curtain is allowed to travel by a shutter release of the camera; upon termination of an exposure time counted by the timer circuit, say, 1/1000 sec., 1/500 sec., etc., a trailing shutter curtain is allowed to travel. However, in a focal plane shutter, the leading and trailing curtains of the shutter must be partially overlapped at the time of shutter charging and before commencement of a shutter operation. Besides, there is some response delay of the magnet arranged to hold the trailing curtain. Accordingly, the starting positions of the leading and trailing shutter curtains differ from each other, while the response delay of the magnet makes it impossible to have the actual length of film exposure time coincide with the counted length of exposure time. Therefore, it has been impossible to accomplish precise exposure control through the mere arrangement of starting a time counting operation concurrently with the travel of the leading shutter curtain, and allowing the trailing shutter curtain to travel upon completion of the time counting operation.
To solve this problem, in the conventional cameras using focal plane shutters, an adjusting time Tx is arranged in addition to the exposure time. More specifically, the delay time Tmg of the magnet, the overlapping time Tg of the shutter curtains, the exposure count time Te and the actual length of film exposing time TA are in the following relation: TA+Tg =Te+Tmg. The film exposing time TA, therefore, can be expressed as follows: TA=Te+Tmg-Tg. It is impossible to obtain a relation of TA=Te. The exposure count time and the film exposing time thus never coincide with each other. Accordingly, it is necessary to obtain the relation of TA=Te by adjusting the travelling time of the shutter curtains and the counting time. However, to accomplish this adjustment in a mechanical manner is difficult because the overlapping degree of shutter curtains and the response delay of the magnet of one camera differ from those of another. To overcome this difficulty, in the conventionally practiced method, an adjusting time Tx is added to the count time Te through a timer circuit; and the relation of TA=Te is obtained by actuating the trailing curtain holding magnet after the lapse of a length of time Te+Tx (hereinafter this method will be called the plus exposure time adjusting method).
In other words, the conventional devices are arranged to have a relation of Te+Tx+Tmg=Tg+TA and the Tx is adjusted to become Tg-Tmg through the timer circuit. A relation of Te=TA is realized by equalizing the count time Te with the film exposing time TA through the above stated adjustment.
The adverse effect which is caused to take place to uneven degrees in cameras, by the overlapping time Tg of the shutter curtains and the response delay time Tmg of the magnet, thus has been simply coped with by equalizing the count time and the film exposing time to each other through the adjustment time Tx=Tg-Tmg provided by the timer conduit.
However, even with the above stated method, the relation of Te=TA becomes hardly realizable, and there arises an exposure error in cases where the shutter curtain overlapping time Tg is shorter than the response delay time Tmg of the magnet. In other words, since the adjustment time Tx is Tg-Tmg, in the case of Tg<Tmg, the adjustment time Tx becomes Tx<0 which makes the adjustment hardly possible. To solve this problem, an exposure control circuit has recently been proposed as disclosed in a U.S. patent application, Ser. No. 144,981, filed Apr. 30, 1980. In accordance with the method of this exposure control circuit (hereinafter called the minus exposure time adjusting method), the count time Te for the exposure is arranged to be shorter than the film exposing time TA for exposing the film surface to a proper degree, such as 1/1000, 1/500, etc., by a predetermined length of time Tc, such as 0.5 msec. In short, the above stated problem is solved by obtaining a relation of TA-Tc=Te.
More specifically stated, in the formula given above, Te+Tmg+Tx=Tg+TA, Te is arranged to be TA-Tc to obtain a relation of TA-Tc+Tmg+Tc. With this arrangement employed, even when an increase in the shutter curtain travelling speed results in a relation of Tg<Tmg, time adjustment can be accomplished through the adjustment time Tx so long as the relation does not become Tg+Tc<Tmg. Therefore, in accordance with the minus exposure time adjusting method, the exposure error due to the adjustment time Tx can be corrected. Even when an increase in the travelling speed of the shutter curtains causes the delay time of the magnet to become longer than the overlapping time of the shutter curtains, the exposure error due to the overlapping of the shutter curtains and the response delay of the magnet can be corrected by the adjustment time Tx.
However, since the exposure count time Te is arranged to be shorter than the exposure time TA by a certain predetermined length of time Te in accordance with the proposed method, there is a certain limit to the predetermined time Tc. For example, the limit to the time Tc is 1 msec where the highest shutter speed or time is 1/1000 sec and is 0.5 msec where the highest shutter speed is 1/2000. The time Tc is thus limited by the highest shutter operating speed. Accordingly, adjustment becomes impossible and an exposure error inevitably arises if this limit is exceeded. | {
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With the development of science and technology, the market has placed increasing requirements on various types of display devices. For example, ultra-thin, narrow frames, etc. have become the desired characteristics for many display devices. To this end, it is usually required to improve the design for relevant components of the display device. For example, the backlight module needs to be made thinner to occupy as little space as possible. Therefore, components such as the rubber frame in the backlight module are typically designed to be thinner and narrower. However, the thinner rubber frame is easy to soften, causing trouble in the usage and maintenance for the backlight module, meanwhile it is advantageous for the mechanical strength of the backlight module. To overcome this drawback, some backlight modules are also provided with a backplate structure. However, adding a backplate structure does not coincide with the thinning requirement on the backlight module. | {
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This invention relates generally to popcorn machines and more particularly concerns individual serving popcorn machines operable on demand.
Old time popcorn vending machines relied on the use of a hot plate on which the unpopped kernels were heated until they popped. Machines of this type generally required the use of oil or other lubricants on the surface of the hot plate to prevent sticking or burning of the kernels. To eliminate this problem, more recent popcorn vending machines employ hot air circulatory systems rather than a hot plate. However, presently known hot air vending machines employ such extremely complex measuring and delivery systems, cooking apparata and control circuitry as to be impractical and unmarketable. Moreover, many, though not all, of these systems prepop large quantities of corn for later dispensation of small portions on demand. Consequently, the consumer is not always getting the freshest product. Attempts to devise single-serving-on-demand hot air circulating poppers, have only further complicated the machines, increasing breakdown frequency, raising the cost of the product and requiring large cabinets to house the system.
It is therefore an object of this invention to provide an individual serving, hot-air-circulating popcorn popper. A further object of this invention is to provide a popcorn popper which will rapidly prepare individual servings of popcorn upon demand. It is also an object of this invention to provide a popcorn popper that is small in size, low in cost and easy to maintain. | {
"pile_set_name": "USPTO Backgrounds"
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Intravascular ultrasound (IVUS) imaging is widely used in interventional cardiology as a diagnostic tool for assessing a vessel, such as an artery, within the human body to determine the need for treatment, to guide intervention, and/or to assess its effectiveness. An IVUS imaging system uses ultrasound echoes to form a cross-sectional image of the vessel of interest. Typically, IVUS imaging uses a transducer on an IVUS catheter that both emits ultrasound signals (waves) and receives the reflected ultrasound signals. The emitted ultrasound signals (often referred to as ultrasound pulses) pass easily through most tissues and blood, but they are partially reflected at impedance discontinuities arising from tissue structures (such as the various layers of the vessel wall), red blood cells, and other features of interest. The IVUS imaging system, which is connected to the IVUS catheter by way of a patient interface module, processes the received ultrasound signals (often referred to as ultrasound echoes) to produce a cross-sectional image of the vessel where the IVUS catheter is located.
One preferred type of ultrasound transducer for IVUS imaging is the piezoelectric micromachined ultrasound transducer (PMUT), which is a microelectromechanical system (MEMS) device, typically fabricated in large batches on a silicon wafer substrate. MEMS fabrication techniques are used to produce thousands of PMUTs on a single silicon wafer. Typically, a PMUT may be formed by depositing a piezoelectric polymer onto a micro-machined silicon substrate. The silicon substrate may also include electronic circuitry used to provide an electrical interface to the transducer. Alternatively, the electronic circuitry associated with the PMUT may be contained in a separate application-specific integrated circuit (ASIC) which is located in close proximity to the PMUT device and connected by electrical leads. The PMUT MEMS device with its associated electronic circuit (either included on the same substrate or located on a separate adjacent ASIC), with an attached length of electrical cable is referred to as a tadpole assembly based on its configuration consisting of a somewhat bulbous transducer assembly coupled to a long tail-like electrical cable. Currently, PMUT tadpole assemblies are coated with Parylene to insulate the front electrode and other electrical connections from contact with fluids (e.g., saline or blood). This is inconvenient, since it is complicated to introduce a large number of tadpole assemblies into the Parylene chamber and to protect the attached electrical cables from being coated.
Therefore, while conventional wafer fabrication techniques and methods of coating a protective layer on transducer assemblies at the tadpole stage are generally adequate for their intended purposes, they have not been entirely satisfactory in every aspect. | {
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The invention relates to supporting substrates in a near vacuum or other low-pressure processing environments using thermally conductive as well as temperature-regulating chucks for transferring heat to or from the substrates.
Vacuum processing operations take place in vacuum chambers that provide near vacuum or other low-pressure environments for processing substrates. Chucks support the substrates within the processing chambers. Some such chucks merely provide a substrate support platform and rely on gravity to hold the substrates in place. Others actively secure the substrates with either mechanical or electrostatic clamps.
Some chucks are also involved with the processing of the substrates by producing electrical or magnetic fields or by regulating heat transfers to or from the substrates. Such electrical fields (e.g., bias) can be used to generate or enhance a plasma as well as to direct plasma ions impinging on the substrate. Such magnetic fields can be used to also influence the plasma or to magnetically orient films during plasma-assisted deposition or thermal anneals. Heat transfers are used to remove excess heat from the substrates produced by such processing operations or to provide a controlled amount of substrate heating for assisting such processing operations. Some operations are best performed at fixed substrate temperatures or at substrate temperatures that are adjusted throughout different stages of the operations. Plasma sputtering operations such as chemical-vapor deposition (CVD) and metal-organic chemical-vapor deposition (MOCVD) require active substrate heating, while other sputtering operations require active substrate cooling. During operations like thermal annealing, elevated temperatures actually accomplish the substrate processing.
However, controlling substrate temperatures in near vacuum or other low-pressure environments is quite difficult because heat does not transfer well between objects in such environments. For example, the conduction of heat between contiguous surfaces of a chuck body and the substrate in a low-pressure environment is slow and inefficient because actual contact on an atomic scale between the surfaces is limited to a small fraction of their common areas, and gaps that separate the remaining common areas of their surfaces prevent effective heat transfer by conduction.
Heating and cooling of substrates through radiational heat transfers are possible in low-pressure environments, particularly at elevated substrate and chuck temperatures, but radiational heat transfers are generally too slow to maintain substrates at desired processing temperatures. Below 500xc2x0 C., which includes most chuckbased fabrication processes, radiational heat transfers are too inefficient to regulate substrate processing temperatures.
Faster transfers are possible by pumping a gas, preferably an inert gas such as helium or argon or another gas such as nitrogen or hydrogen, between the chuck body and the substrate. Although still at much less than atmospheric pressure (e.g., 1 Torr to 20 Torr), the gas (referred to as xe2x80x9cbackside gasxe2x80x9d) sufficiently fills the small gaps between the chuck body and the substrate to support significant heat transfer through thermal conduction between them. A seal formed between the mounting surface of the chuck body and the substrate resists significant leakage of the gas into the rest of the processing chamber, which could disturb substrate processing operations.
U.S. Pat. No. 4,680,061 to Lamont, Jr. discloses chucks having heating or cooling elements for regulating substrate temperatures. One of the chucks has a ceramic heating element mounted in a cavity between a chuck body and a substrate. The heating element is mounted close to a back side of the substrate but not in contact. Argon gas is introduced into the cavity to promote heat exchanges between the heating element and the substrate. A raised rim of the chuck body on which the substrate is mounted contacts a peripheral portion of the substrate""s back side forming a seal that inhibits leakage of the gas out of the cavity.
Another of Lamont, Jr.""s chucks has a chuck body that functions as a heat sink with coolant channels for removing heat from the sink. A similar cavity is formed by a raised rim in the chuck body so that the remaining heat sink is positioned close but not in contact with the back side of a substrate. Argon gas is similarly trapped within the cavity by contact between the raised rim of the chuck and the back side of the substrate. Thus, the raised rim that supports the substrate also functions as a seal for inhibiting leakage of the gas into the rest of the processing chamber.
U.S. Pat. No. 4,949,783 to Lakios et al. also discloses a chuck using gas pressure against a back side of a substrate to promote substrate cooling. A similar cavity is formed in the chuck body and surrounded by a raised rim for contacting the back side of the substrate. However, instead of merely pumping backside gas into the cavity, Lakios et al. circulate the backside gas both into and out of the cavity by establishing a gas flow. Part of the heat transfer from the substrate is due to gas-conducted heat exchanges with the chuck body, and another part of the heat transfer is due to the removal of heated gas from the cavity.
The chucks of both Lamont, Jr. and Lakios et al. include raised rims on their chuck bodies that function as both mounting surfaces and seals. Mechanical clamps press the substrates against the raised rims of their chuck bodies to tighten the seals and to reduce leakage of backside gas into their processing chambers. Lakios et al. also use an O-ring seal next to their raised rim to provide an even tighter seal for further reducing leakage. However, such O-ring seals are normally not useable for elevated substrate-temperature processing (e.g., above 200xc2x0 C.) because of thermal limitations of elastomer seals.
The raised rims of the prior chucks separate conductive portions of the chuck body from the substrate, which reduces efficiency of heat transfers between them. Also, some leakage of substrate backside gas can occur through the raised rims, particularly through rims made to withstand elevated temperatures during substrate heating operations. Substrate back side surface roughness can also reduce the effectiveness of the raised rim seals and lead to excessive leakage of backside gas into the processing region of the processing chamber.
This invention in one or more of its embodiments improves chucks that use gas or other fluid as a medium for transferring heat to or from substrates in a vacuum processor by providing a two-stage sealing system that reduces leakage of the gas from between the chucks and the substrates into the processing region of the vacuum processor. A first sealing stage confines the gas between preferably contiguous first portions of the chucks and substrates for supporting transfers of heat. A second sealing stage collects gas escaping through the first sealing stage into an intermediate space between second portions of the chucks and substrates at a reduced pressure with respect to the pressure at which the gas is confined within the heat-transfer interface.
The processing region of the vacuum processor is a first pressure-regulatable space. The first sealing stage together with the first portions of the chuck and substrate forms a second pressure-regulatable space, and the second sealing stage together with the second portions of the chuck and substrate forms a third pressure-regulatable space. Pressure in the third pressure-regulatable space is reduced with respect to pressure in the second pressure-regulatable space to further inhibit leakage of gas from the second pressure-regulatable space into the first pressure-regulatable space.
One particular embodiment includes a chuck body having a mounting surface that supports the substrate for processing within the first pressure-regulatable space of the processing chamber. The mounting surface forms together with the substrate a second pressure-regulatable space for assisting transfers of heat between the chuck body and the substrate. A clamp presses the substrate against the mounting surface and forms together with the chuck body and the substrate a third pressure-regulatable space that extends beyond a periphery of the substrate between the first and second pressure-regulatable spaces.
The substrate includes a front surface (usually comprising devices in various stages of fabrication) exposed to pressure in the first pressure-regulatable space and a back surface exposed to pressure in the second pressure-regulatable space. The mounting surface contacts the back surface of the substrate for inhibiting flows of fluid (e.g., backside gas) between the second and third pressure-regulatable spaces. The clamp contacts the front surface of the substrate and the chuck body (or an extension of the chuck body) for inhibiting flows of fluid between the first and third pressure-regulatable spaces.
The mounting surface and the back surface of the substrate are preferably contiguous over most of their common overlapping areas to enhance transfers of heat between them. Channels in the mounting surface interrupt a central portion of the common area to circulate gas within the second pressure-regulatable space, while a surrounding portion of the common area remains uninterrupted to provide the first-stage seal.
A recess in the clamp or the chuck body provides an enclosed cavity or manifold for collecting gas within the third pressure-regulatable space. One second-stage seal joins the clamp to the front surface of the substrate, and another second-stage seal joins the clamp to the chuck body. One of the second-stage seals is preferably mounted from a flexible portion of the clamp to assure contact at both second-stage seals of the clamp as well as the first-stage seal between the mounting surface of the chuck body and the substrate.
Inlet and outlet conduits preferably provide a continuous flow of gas through the second pressure-regulatable space. Separately controlled outlet conduits can be used to remove gas from the third pressure-regulatable space for reducing the pressure in the third pressure-regulatable space with respect to the pressure in the second pressure-regulatable space and for minimizing substrate backside gas leakage into the processing portion of the processing chamber (i.e., the first pressure-regulatable space).
Another embodiment can be described as having first and second substrate mounting components for mounting a substrate for processing in a first pressure-regulatable space and for forming together with the substrate second and third pressure-regulatable spaces. The first substrate mounting component, which is in thermal communication with a temperature-regulating (e.g., heating or cooling) element, has a first-stage seal surrounding a central portion of the substrate for confining fluid (e.g., backside gas) within the second pressure-regulatable space. A second substrate mounting component, which is at least partially thermally isolated from the temperature-regulating element and the first substrate mounting component, has at least one second-stage seal surrounding the second pressure-regulatable space for confining fluid within the third pressure-regulatable space in substantial isolation from the first pressure-regulatable space. A control system reduces pressure in the third pressure-regulatable space with respect to pressure in the second pressure-regulatable space to inhibit leakage of fluid from the second pressure-regulatable space into the first pressure-regulatable space.
The first substrate mounting component can include a chuck body having a mounting surface that supports the substrate for processing within the first pressure-regulatable space of the processing chamber. The second substrate mounting component can take various forms including a mechanical clamp as described above or a peripheral support surrounding the chuck body. In the latter case, the mounting surface can be built up from alternating layers of electrically conductive and non-conductive films patterned as electrodes to form an electrostatic clamp for pressing the substrate against the chuck body as well as the peripheral support. A first second-stage seal joins the peripheral support to the back surface of the substrate, and a second second-stage seal joins the peripheral support to the chuck body or an extension of the chuck body. The second second-stage seal can join the peripheral support directly to a heat-conducting portion of the chuck body or indirectly through a thermal insulator. Particularly during heating operations, the peripheral support is preferably constructed to minimize transmissions of heat with either the substrate or the chuck body.
Since the second substrate mounting component (e.g., peripheral support) is interposed between the heat-conducting portion of the chuck body and the first second-stage seal, more options are available for regulating temperatures at the first second-stage seal. For example, the second substrate mounting component can function as a thermal insulator during heating operations to lower temperatures at the first second-stage seal. The area of the second substrate mounting component exposed to gas within the third pressure-regulatable space and the proximity of the second substrate mounting component to the heat-conducting portion of the chuck body are other design variables that can be used to regulate thermal conduction of the second substrate mounting component. | {
"pile_set_name": "USPTO Backgrounds"
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An Electro-Photography (EP) printing device forms an image on media typically by first selectively charging a photoconductive drum in correspondence with the image. Colorant is applied to the photoconductive drum where the drum has been charged, and then this colorant is transferred to the media to form the image on the media. Liquid Electro-Photographic (LEP) printing devices employ liquid ink that contains a carrier fluid and pigment solids which are suspended in the carrier. During printing, the carrier fluid allows the solid particles to be mixed, transported, and deposited on the photoconductive drum. The liquid ink is applied to the photoconductive drum where the drum has been charged. Before the solid particles are deposited on the substrate, the majority of the carrier fluid is extracted. A large percentage of the carrier fluid is captured and recycled. However, during the printing process excessive carrier accumulates in the printing system and is discarded.
Throughout the drawings, identical reference numbers designate similar, but not necessarily identical, elements. | {
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The present invention concerns detection of phase shift modulation in amplitude modulated optical radiation. Such phase shift modulation is employed in laser communications and in laser ranging.
In laser communications systems of this type a laser beam is amplitude modulated by a lower frequency signal, typically in the radio frequency (RF) signal range. Information is imparted to the RF modulation signal by phase shift modulation relative to a stationary signal. The information is extracted at the receiver by demodulation of the phase shift modulation signal.
Laser ranging systems include the so called "three dimensional" laser imaging systems. These systems permit the detection of the range to every picture element of a scene. In such systems the scene to be imaged is illuminated by a laser and the reflected signal is received and detected via a sensor. Typically the laser and the sensor with their accompanying optics are disposed side-by-side or along the same optical axis so that the laser illuminates the same small area of the scene as viewed by the sensor. The scene to be imaged is scanned by moving this combination or by using moving reflectors.
Modulation of the laser source enables range information to be obtained. The laser source is modulated with an RF signal. This modulation signal is extracted from the reflected signal received by the sensor. The modulation signal in the reflected signal is phase shifted from the original modulation signal by an amount equal to the round trip transit time.
In the prior art the received signal is detected via a photosensor. The photosensor output is amplified and the signal demodulated to extract the modulation signal. The extracted modulation signal is compared with the signal of the original modulation source to determine the phase difference. This phase difference corresponds to the information imparted in a communication system. In a three dimensional laser imaging system this phase difference is a measure of the range to the area currently viewed by the sensor. In three dimensional laser imaging systems the modulation frequency is selected so that the range measurements of interest, which may be the relative ranges of a feature rather than the total range, are less than the 360 degree phase ambiguity inherent in this technique.
There is a problem with such a system that causes the accuracy of phase difference detection to be reduced. The magnitude of the received signal can vary by several orders of magnitude. In communications systems this variation is primarily due to variations in range or alignment between the transmitter and the receiver, or due to attenuation along the propagation channel. In three dimensional laser imaging systems the amplitude of the received signal may vary due to regions of differing reflectivity within the scene, or by random interference effects within the reflected radiation which is known as speckle. The electronic amplifier coupled to the photosensor typically has a differing phase shift dependent upon the magnitude of the signal received. Thus the strength of the received signal interferes with the accuracy of the phase difference measurement. This problem is called amplitude-phase crosstalk. There have been previous attempts to reduce this amplitude dependent phase shift in the amplifier or to measure and correct for this crosstalk with limited success.
There is therefore a need for a phase difference detector which has a minimum of amplitude-phase crosstalk. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to inexpensive process and reactor modifications for the reduction of nitrogen oxides (NOx) emissions from catalytic cracking regenerators. More specifically, this invention relates to operating the regenerator such that up to about 1% carbon monoxide (CO) exits the dense catalyst zone, and to modifications that provide for the introduction of secondary oxygen-containing gas streams and, optionally, shield gas stream or streams into the dilute phase of the regenerator, thereby eliminating the majority of NOx emissions without producing significant CO emission and reducing temperature rise due to afterburn.
In the fluid catalytic cracking (FCC) process, hydrocarbon feedstock is injected into the riser section of a hydrocarbon cracking reactor where it cracks into lighter, valuable products on contacting hot catalyst circulated to the riser-reactor from a catalyst regenerator vessel. As the endothermic cracking reactions take place, the catalyst is covered with coke deposits. The catalyst and hydrocarbon vapors are carried up the riser to the disengagement section of the reactor where they are separated. Subsequently, the catalyst flows into the stripping section where the hydrocarbon vapors entrained with the catalyst are stripped by steam injection, and the stripped catalyst flows through a spent catalyst standpipe and into the catalyst regenerator vessel.
The regenerator vessel is operated as a fluid bed reactor with the catalyst forming a dense phase in the lower section of the reactor and a dilute phase above the dense phase. Air or oxygen-enriched air is introduced through an air grid located in the dense phase near the bottom of the vessel. When the coke-laden catalyst comes in contact with the air the coke is burned forming CO and carbon dioxide (CO2), which, along with the nitrogen in the air, pass upwards through the dense phase, into the dilute phase, and then exits the regenerator. These gases constitute the majority of the flue gas. During the coke combustion process, any nitrogen containing species present in the coke also react with oxygen to form mostly elemental nitrogen (N2) and a small amount of NOx. These species, along with any sulfur oxides (SOx) formed by the combustion of sulfur present in the coke, also travel with the CO/CO2/N2 through the regenerator. The region of the reactor near the air grid, within the dense phase, has a high oxygen concentration that constitutes the oxidizing zone. Away, or downstream from the air grid, as oxygen is depleted, a reducing zone forms, where the CO concentration is significant. The CO continues to react with the remainder of the oxygen to form CO2. In the reducing zone, NOx species also react with CO to form elemental nitrogen. Depending on the concentration of CO and CO2 in this zone, more or less NOx will react.
The catalyst regeneration vessel may be operated in the complete CO combustion mode, which has now become the standard combustion mode, or in partial CO combustion mode. In the complete combustion operation, the coke on the catalyst is oxidized completely to form CO2. This is typically accomplished by conducting the regeneration in the presence of excess oxygen, provided in the form of excess air. The exhaust gas from a complete combustion operation comprises primarily nitrogen, CO2, H2O and excess oxygen, but also contains NOx and SOx.
In the partial CO combustion mode of operation, the catalyst regeneration vessel is operated with insufficient oxygen to fully oxidize all of the coke in the catalyst to CO2. Consequently the coke is combusted to a mixture of CO and CO2. The remaining CO is oxidized to CO2 in a downstream CO boiler. When the regeneration vessel is operated in the partial CO combustion mode, less NOx is produced, and that which is produced reacts with CO in the reducing zone to form elemental nitrogen. Instead, nitrogen species in the coke leave the regeneration vessel as reduced nitrogen species, such as, ammonia and HCN. However, the reduced nitrogen species are unstable in the CO boiler, where they are converted to NOx. Thus the effluent from the CO boiler comprises primarily nitrogen, CO2 and H2O, but also contains NOx and SOx.
Recently, there has been considerable concern about the amount of NOx and SOx being released to the environment in refinery flue gases. It is now the accepted view that most of the NOx present in catalyst regenerator exhaust comes from coke nitrogen, i.e., nitrogen contained in the coke in the form of hetero-compounds, such as, condensed cyclic compounds, and that little or none of the NOx contained in the exhaust gas is derived from the nitrogen contained in the air feed to the regeneration vessel.
Several approaches have been used in industry to reduce NOx in FCC regenerator vessel exhaust gases. These include capital-intensive and expensive options, such as pretreatment of reactor feed with hydrogen, and flue gas post-treatment options, such as Selective Catalytic Reduction (SCR), as well as the use of in-situ FCC catalyst additives. A number of other methods have also been contemplated for NOx reduction, as discussed below.
U.S. Pat. No. 5,268,089 discloses that NOx can be reduced by operating the regenerator xe2x80x9con the brinkxe2x80x9d, i.e., in a region between conventional partial CO combustion operation and complete combustion operation with less than 2 mol % CO in the flue gas. The patent claims NOx reduction by operating in this mode. However, a CO boiler is still required to burn the CO exiting from the regenerator, as is the case in the partial combustion mode of operation. Furthermore, while U.S. Pat. No. 5,268,089 discloses the existence of afterburn as a result of operating xe2x80x9con the brinkxe2x80x9d, a solution to avoid or mitigate the overheating in the dilute phase due to afterburn is not disclosed.
Several patents disclose the reduction of NOx in FCC regenerators by means of promoters, segregated feed cracking, post treatment of exhaust gas, etc. These patents are discussed in detail in U.S. Pat. No. 5,268,089, the disclosure of which is incorporated herein by reference.
U.S. Pat. Nos. 5,705,053, 5,716,514, and 5,372,706 each disclose variations of the basic idea of controlled air addition to flue gas from a regenerator operated in the partial combustion mode, before the CO boiler, to convert part of the NOx precursor species (HCN, NH3) selectively to N2 rather than NOx. Consequently, in the CO boiler, less NOx is generated. In U.S. Pat. No. 5,705,053 an additional catalytic step is suggested for NOx/NH3 reaction. In U.S. Pat. No. 5,372,706, the thermal conversion of NOx precursors is claimed at temperatures between 2000 and 2900xc2x0 F. In U.S. Pat. No. 5,716,514 flue gases are specifically removed from the regenerator and comprise at least 2.5% carbon monoxide. These gases are reacted in a separate turbulent flow reactor. In all of these patents, the secondary air addition is aimed at reacting part of the NH3/HCN formed due to the partial combustion operation.
U.S. Pat. No. 5,240,690 suggests a partial combustion mode of operation and the addition of air to the regenerator off-gas comprising at least 1% carbon monoxide to oxidize NH3/HCN and preferentially produce N2 prior to the CO boiler.
Efforts are continuously underway to find new and improved methods of reducing the concentrations of NOx and SOx in industrial flue gases, such as, FCC regeneration vessel exhaust gases. Notably absent from the prior art is the introduction of secondary oxygen-containing gases, optionally with shielding gases, into the dilute phase of the regeneration vessel, which is primarily operated in a complete combustion mode, whereby the majority of NOx is eliminated, CO is converted to CO2, and the temperature rise due to after burn is controlled.
The present invention provides inexpensive regeneration vessel modifications that significantly reduce NOx emissions by concurrently introducing secondary oxygen-containing gases, optionally with shielding gases, into vessel which is operated in a manner that does not require the use of a CO boiler. The present invention provides means to eliminate the majority of NOx emissions from a FCC regenerator.
The present invention is directed to a process for substantially reducing the emission of nitrogen oxide from a regeneration reactor during the regeneration of a spent catalyst, such as, a hydrocarbon cracking catalyst, having coke deposits thereon, which comprises the steps of:
(a) contacting the spent catalyst with a primary oxygen-containing gas in the dense phase of the reactor, thereby combusting the coke and forming a combustion gas comprising nitrogen oxide and carbon monoxide which further react in said dense phase, thus reducing a majority of the nitrogen oxides to form elemental nitrogen, thereby forming a nitrogen-enriched combustion gas; and
(b) contacting the nitrogen-enriched combustion gas in the dilute phase of the reactor with a secondary oxygen-containing gas, wherein the carbon monoxide is oxidized to form carbon dioxide.
The amount of the primary oxygen-containing gas in step (a) is adjusted so that the nitrogen-enriched combustion gas prior to step (b) comprises up to 1% carbon monoxide. As a result of this process, nitrogen oxide emissions from the regeneration reactor are significantly reduced while the temperature rise due to afterburn in the dilute phase is minimized and controlled by the introduction of a shield gas or heat removal devices.
The present invention also employs one or more nozzles configured to allow the secondary oxygen-containing gas, and, optionally, a shield gas, to be introduced into the dilute phase of the regeneration reactor so as to provide combustion conditions, and control the temperature rise due to afterburn in the dilute phase.
The secondary oxygen-containing gas introduced to the reactor oxidizes the residual CO exiting the dense phase. Steam or water may be added to the secondary oxygen-containing gas stream as a shield gas to assist in the even distribution of oxygen across the regenerator vessel and to reduce the temperature rise in the dilute phase due to the combustion of CO. The location of the one or more nozzles feeding the steam or water is selected such that there is minimal contact of steam with the majority of the catalyst, thereby avoiding catalyst deactivation. The excess heat generated in the dilute phase due to the exothermic CO oxidation may also be removed by other means, such as, for example, with a cooling coil located in the dilute phase.
The present invention may also be configured in such a manner that the secondary oxygen-containing gas is introduced in different stages at different vertical heights in the reactor vessel. For example, a portion of the secondary oxygen-containing gas may be introduced to the reactor at or just above the interface between the dense phase and the dilute phase, prior to introducing the main secondary oxygen-containing gas, as described above. The secondary oxygen-containing gas introduced at the interface is in an amount sufficient to combust the small amount of residual reduced nitrogen species, such as, NH3 and HCN, contained in the combustion gas to form nitrogen oxides, which are subsequently reacted with CO to form elemental nitrogen. The secondary oxygen-containing gas is then staged or introduced to the dilute phase of the vessel at a point downstream in order to perform the process as described above. The secondary oxygen containing gas may be introduced to the interface between the dense and dilute phases of the reactor with one or more nozzles. Additionally, a shield gas may be introduced with the secondary oxygen-containing gas to assist in the even distribution of oxygen across the vessel and to avoid catalyst deactivation by creating a gas barrier between the steam introduced above that point and the catalyst.
In another embodiment of the present invention, to further eliminate the small amount of CO that may escape from the dilute phase of the regenerator vessel, the secondary oxygen-containing gas is staged or introduced to the exhaust flue of the vessel after carrying out the processes as described above. The oxygen-containing gas oxidizes any remaining CO that may be present in the flue gas, thus forming CO2. The secondary oxygen-containing gas may be introduced to the exhaust flue with one or more nozzles. Additionally, a shield gas may also be introduced to assist in the even distribution of oxygen across the exhaust duct and control the temperature rise due to afterburn.
Significant cost savings relative to the large reduction in NOx occur since no separate NOx removal equipment is required downstream. In addition, the process of the present invention is advantageous since it involves minimal modifications to the existing regeneration vessel and associated equipment, compared to installation of a secondary air grid. Furthermore, because there is virtually no CO exiting the reactor, no downstream carbon monoxide boiler is required.
The present invention is also directed to a catalyst regeneration vessel having a dense phase and a dilute phase comprising:
(a) a means for introducing a primary oxygen-containing gas into the dense phase of the regeneration vessel; and
(b) a means for introducing a secondary oxygen-containing gas into the dilute phase of the regeneration vessel.
In one embodiment of the present invention, the regeneration vessel is a reactor. Preferably, a means for introducing a primary oxygen-containing gas to the reactor is an air grid located in the dense phase. In addition, preferably, one or more means for introducing a secondary oxygen-containing gas, and optionally a shield gas, into the reactor is in the form of nozzles, which are located in the side walls and/or the dome of the reactor at various angles and heights. In another embodiment of the present invention, the reactor has a means for staging the introduction of the secondary oxygen-containing gas to the dilute phase of the reactor at or just above the interface with the dense phase. In yet another embodiment of the present invention, the reaction vessel has a means for staging the introduction of the secondary oxygen-containing gas to the exhaust flue of the vessel. | {
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1. Technical Field
The present invention relates to storage systems and, more particularly, to access-based enumeration of shared resources in such systems.
2. Background Information
A storage system typically includes one or more storage devices, such as disks, into which information may be entered, and from which information may be obtained, as desired. The storage system may also include a storage operating system that may implement a high-level module, such as a file system, to logically organize the information stored on the disks as a hierarchical structure of data containers, such as files and directories. In addition, the storage system may be configured to operate according to a client/server model of information delivery to thereby allow many clients to access the data containers stored on the system. Each client may request the services of the storage system by issuing messages (in the form of packets) to the system using storage (e.g., file-based) access protocols, such as the conventional Common Internet File System (CIFS) protocol.
To facilitate client access to the information stored on the storage system, the storage operating system typically exports units of storage, e.g., (CIFS) shares. As used herein, a share is equivalent to a mount point or shared storage resource, such as a folder or directory that stores information about files or other directories served by the system. A client access feature of the storage system may be to provide an ordered listing or “enumeration” of data containers within a share, or a portion of the share, served by the storage system. Typically, a client issues an enumeration request on behalf of a user to solicit enumeration of the data containers within a directory of the share. In response, the storage system returns a list of descriptors for those data containers included in the directory specified in the enumeration request. The response typically contains only those descriptors for which the user making the enumeration request has sufficient access permission.
Conventionally, access permission is determined per export unit, e.g., per share, as a property of the whole share. Consequently, a user with permission to access the share may have sufficient permission to view a descriptor of any file or folder served by the share, even if that user has insufficient permission to access the files or folders themselves. Security problems may arise for enumeration requests when descriptors of files and folders are visible to a user who doesn't have sufficient permission to access those files and folders. For example, the name of a file or folder may describe confidential information, such as the name of a customer or a new product under development. To remedy this problem, access permission may be determined using access-based enumeration (ABE), which lists descriptors of enumerated data containers based on a user's access permission to those data containers. A user without sufficient permission to access a data container is deemed to have insufficient permission to access a descriptor of the data container.
A further security problem arises with access-based enumeration of junctions or mount points. As used herein, a junction or mount point is an identifier that redirects access to a data container to a storage location referenced by the junction rather than the location containing the junction or mount point; however, permission to access the data container may appropriately reside at the reference location. For example, the administrator may alter the access permission of the data container at the reference location leaving any permission stored at the location of the junction or mount point unaltered. Failure to apply the appropriate user access permission of the data container at the reference location, in response to an enumeration request, may result in a security breach in which a descriptor of a junction or mount point is provided to a user with insufficient permission to access the contents of the data container referenced by that junction or mount point. The problem may be compounded when further indirection is employed, such as when a junction references a data container at another storage location and that data container includes another junction that references yet another data container at yet another storage location, and so on.
Accordingly, there remains a need for a method and system for secure access-based enumeration of junctions or mount points on a server. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a method of producing stacks of sheets printed with individual prints, in particular stacks of securities sheets, such as banknotes, from stacks of unprinted sheets, the unprinted sheets running into a printing machine one after another in order to be provided with the individual prints.
The present invention likewise relates to a printing machine for the implementation of the method according to the invention. | {
"pile_set_name": "USPTO Backgrounds"
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Metal halide lamps began with the addition to the high pressure mercury lamp of the halides of various light-emitting metals in order to modify its color and raise its operating efficacy as proposed by U.S. Pat. No. 3,234,421--Reiling, issued in 1966. Since then metal halide lamps have become commercially useful for general illumination; their construction and mode of operation are described in IES Lighting Handbook, 5th Edition, 1972, published by the Illuminating Engineering Society, pages 8-34.
The light-emitting metals favored by Reiling for addition to the arc tube fill were sodium, thallium and indium in the form of iodides. This combination had the advantage of giving a lamp starting voltage almost as low as that of a mercury vapor lamp, thus permitting interchangeability of metal halide with mercury lamps in the same sockets. A later U.S. Pat. No. 3,407,327--Koury et al issued in 1968, proposed as additive metals sodium, scandium and thorium; that fill is now favored because it produces light of somewhat better spectral quality. Unfortunately, it also entails a higher starting voltage so that the lamp is not generally interchangeable with mercury vapor lamps.
In the earlier thallium-containing metal halide lamps, the electrodes used comprised tungsten coils carrying thorium oxide in the turns. In operation, the thorium oxide is believed to decompose slightly and release free thorium to supply a monolayer film having reduced work function and higher emission. Unfortunately, this cathode cannot be used in a scandium-containing lamp because the ScI.sub.3 is converted to Sc.sub.2 O.sub.3, resulting in loss of essentially all the scandium in a relatively short time. Instead a thorium-tungsten electrode is used which is formed by operating a tungsten cathode, generally a tungsten rod having a tungsten coil wrapped around it to serve as a heat radiator, in a thorium iodide-containing atmosphere. Under proper conditions the rod acquires a thorium spot on its distal end which serves as a good electron emitter and which is continually renewed by a transport cycle involving the halogen present which returns to the cathode any thorium lost by any process. The thorium-tungsten electrode and its method of operation are described in Electric Discharge Lamps by John F. Waymouth, M.I.T. Press, 1971, Chapter 9.
We find that the proper operation of the thorium transport cycle is suppressed when excess iodine is present. In a cool lamp at room temperature the excess iodine is present as HgI.sub.2. When the lamp operates, this mercury iodide decomposes and the free iodine reacts with the thorium at the electrode. The thorium concentration at the electrode tip is governed by the equilibrium expression: EQU Th(c)+4I(g).revreaction.ThI.sub.4 (g)
In the presence of high iodine concentrations, the forward reaction favoring the formation of ThI.sub.4 predominates. At sufficiently high iodine concentrations, no thorium is deposited on the electrode at all, and the result is a high work function electrode. The electrode must then run hotter to sustain the arc current and this entails lower efficiency most noticeable in the smaller sizes of lamps. The higher temperature makes the lamp blacken due to tungsten evaporation and the result is a poor maintenance lamp.
In one manufacturing process, the lamps are dosed with mercury as liquid and with the iodides of Na, Sc, and Th in pellet form. In this process, it is practically unavoidable that some hydrolysis reaction occurs due to absorption of moisture from the atmosphere by the pellets in transferring them to the lamp envelope. The metal halide dose comprising NaI, ScI.sub.3 and ThI.sub.4 is extremely hygroscopic and even very low levels of moisture will result in some hydrolysis. The hydrolysis results in conversion of the metal halide to oxide with release of HI, for example: EQU 2ScI.sub.3 +3H.sub.2 O.fwdarw.Sc.sub.2 O.sub.3 +6HI
The HI reacts with mercury to form HgI.sub.2 which is relatively unstable at high temperatures, and when the lamp warms up, the HgI.sub.2 decomposes and releases free iodine. Some excess iodine also is frequently found in the dosing materials, possibly as a byproduct of the synthesis of these materials. The result is a lamp which frequently contains excess iodine from the start.
In another manufacturing process, part of the mercury and the halogen component of the charge are introduced into the lamp envelope in the form of HgI.sub.2 and scandium and thorium are added as elements. By varying the ratio of Hg to HgI.sub.2, the iodine may be made substoichiometric relative to the Sc or Th present, in which case the lamp begins its life with no excess iodine. However we have found that a slow reaction between the scandium and thorium iodides and the fused silica arc tube gradually frees iodine during the course of the lamp's life. As the free iodine concentration builds up, a point is reached where thorium ceases to be deposited on the electrode at all and the result is a high work function electrode.
Thus prior art lamps, no matter by what process made and even when they begin life without an excess of iodine, eventually arrive at a condition of excess iodine concentration which reduces lamp efficacy and results in an increased rate of blackening and lumen depreciation. The object of the invention therefore is to provide control of excess iodine throughout the full period of the lamp's life in order that the lamp have higher efficiency, better maintenance and a longer useful life. | {
"pile_set_name": "USPTO Backgrounds"
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(i) Field of the Invention
This invention relates to novel phosphoric esters and more particularly, to phosphoric esters of the general formula (I) ##STR2## in which R.sub.1 represents a saturated or unsaturated, linear or branched and substituted or unsubstituted hydrocarbon group having from 8 to 32 carbon atoms, R.sub.2, R.sub.3 and R.sub.4 are the same or different and represent a saturated or unsaturated hydrocarbon group having from 1 to 4 carbon atoms, R.sub.5 represents a hydrogen atom a saturated or unsaturated hydrocarbon group having from 1 to 4 carbon atoms, and n is an integer of from 0 to 56.5.
The invention also relates to a method for preparing the phosphoric acids of the type indicated above.
(ii) Description of the Prior Art
As phosphoric esters having quaternary ammonium salts in one molecule thereof, there are known phospholipids, typical of which is natural lecithin. These phospholipids have surface activity, emulsifiability and physiological characteristics and are thus used in various fields.
A number of substances are currently used as detergents, including alkylsulfates, polyoxyethylene alkylsulfates, alkylbenzenesulfonates, alphaolefinsulfonates, monoalkyl phosphates, acylglutamic acid salts, and the like. These surface active agents, in most cases, bring about chapping of skin. For the purpose of low skin irritations, there are now used monoalkyl phosphates and acylglutamic acid salts.
As is well known, a number of phosphoric ester derivatives such as phospholipids exist in living body, so that it will be expected that substances having structures similar to those of phosphoric ester derivatives, e.g. phosphoric esters having quaternary ammonium salts in one molecule thereof, have low irritations against living body.
However, it is usually very difficult to prepare phospholipids: the preparation generally needs a number of steps, resulting in a low yield of an intended product (see, for example, E. Baer et al; J. Amer, Chem. Soc. 72, 942(1950), and "Lipids" edited by Tamio Yamakawa and published by Kyoritsu Pub. Co., Ltd. (1973)).
The results of several studies on synthesis of compounds having structures similar to those structures of phospholipids have been reported. However, these reactions comprise a number of complicate steps, or may, in some cases, need starting materials which are difficult to prepare. Alternatively, an intended product obtained after the reaction may often be very difficult to separate and yield of which is low. In addition, final products have not necessarily adequate surface activity (see, for example, Japanese Patent Publication Nos. 42-23330 and 48-1654, and U.S. Pat. No. 3507937). | {
"pile_set_name": "USPTO Backgrounds"
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With the development of wireless multimedia service, the demands of people for high data rate and user experience are gradually increased and thus higher requirements are raised to system capacity and coverage of the traditional cellular network. In another aspect, the popularization of applications such as social network, near-field data sharing and local advertisement enable people to understand nearby interested people or things and communicate the people, i.e., the demands for proximity services are gradually increased. The traditional cell-based cellular network has obvious limitations in the aspects of support of high data rate and proximity services. Under the background of this demand, a Device-to-Device (D2D) technology which represents a new development direction of future communication technology emerges. By adopting the D2D technology, the burden of the cellular network can be relieved, the battery power consumption of user equipments can be reduced, the data rate can be improved, the robustness of network infrastructure can be improved and the requirements of high data rate service and proximity services are well satisfied.
The D2D technology can work at authorized frequency bands or unauthorized frequency bands and allows a plurality of user equipments which support a D2D function, i.e., D2D User Equipment (UE) to directly discover or directly communicate under the situation that there is network infrastructure or there is no network infrastructure. The application scenarios of D2D mainly include three types:
1) UE1 and UE2 perform communication under coverage of a cellular network, e.g., mode 1 illustrated in FIG. 1, in which user plane data do not pass through network infrastructure;
2) UE in weakly covered areas or non-covered areas perform communication through UE relay covered by a network, e.g., mode 2 illustrated in FIG. 1, in which UE4 with poor signal quality is allowed to communicate with a network through proximity UE3 covered by the network, such that an operator can be helped to expand coverage and improve capacity;
3) Direct communicate between UEs are allowed under a situation that a cellular network cannot normally work in case of earthquakes or emergency situations, e.g., mode 3 illustrated in FIG. 1, in which a control plane and a user plane between UE5, UE6 and UE7 perform one-hop or multi-hop data communication not through network infrastructure.
The D2D technology usually includes a D2D discovery technology and a D2D communication technology:
1) The D2D discovery technology refers to a technology which is used for judging or determining that two or more D2D user equipment are proximity with one another (e.g., within a range that D2D direction communication can be performed) or is used for judging or determining that a first D2D user equipment is proximity to a second D2D user equipment.
2) The D2D communication technology refers to a technology that partial or all communication data between D2D user equipment can be directly communicated not through the network infrastructure.
In D2D communication, in one aspect, D2D UE needs to avoid missing D2D communication data which possibly need to be received, in another aspect, since the D2D UE receives D2D Scheduling Assignment (SA) by adopting a blind detection mode, if a D2D SA receiving resource pool which needs to be monitored is greater, a great amount of UE power consumption will be caused. In addition, when the D2D UE monitors the D2D SA receive receiving resource pool, cellular communication or D2D sending cannot be simultaneously performed, and thereby the cellular communication or D2D sending will be influenced since monitoring time of D2D SA is too long. | {
"pile_set_name": "USPTO Backgrounds"
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A user account may be managed by a server system and accessed from one or more client devices. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a training device utilized to teach a baseball batter to improve his or her swing.
U.S. Pat. No. 4,225,133 to Kiray discloses a device for teaching batting techniques which includes a base platform having a well for the batter's aft or rear foot, an arm that provides a yieldable barrier for the batter's forward foot, and a cord or cable that checks the batter's swing at levels above his strike zone. U.S. Pat. No. 4,577,868 to Kiyonaga discloses a golf swing training device which includes a plurality of aligned pressure sensors for detecting the golfer's shifting weight during the golf swing and memory circuits that are utilized to issue alarms advising the golfer of the proper weight shifts during the golf swing. U.S. Pat. No. 4,955,608 to Dougherty discloses an athletic movement trainer used by tennis players. The trainer has straps that attach to the ankles of the tennis player and a cord extending from those ankle straps to a loop on a belt around the waist of the tennis player. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates generally to valves, and, in particular, to a portable apparatus for machining a valve seat.
2. Description of the Prior Art
A valve seat provides the surface upon which a valve rests to regulate the flow of fluids in piping systems. As such, valve seats are a very important component of a valve system, because failure or erosion of a valve seat results in leakage of the fluid being conveyed. In applications such as power plants, a solid metal valve seat is required because of the extreme pressures and temperatures of the steam, oil, and gases being conveyed. However, even metal valve seats become worn over time, resulting in seepage or leakage.
Valve leakage also results because of the repeated pressure of the valve disk on the seat. As a result, the shape of the valve seat tends to become flattened. Deterioration of the valve seat also occurs because of corrosion, steam and water. In addition, deposits may build up on the valve seat, preventing a tight seal with the disk.
In some applications, replaceable valve seat rings may be utilized, but these types of valve seats also tend to erode and deteriorate. In addition, replaceable seat rings are specially manufactured for only a limited number of valve designs and are simply unavailable for a great many applications.
Therefore, it is typically necessary to replace the entire valve when the valve seat wears away and causes leakage problems. Replacing the entire valve body and interior valve assembly is expensive, time-consuming, and inconvenient. Typically, the valve body is connected with the pipeline by means of welding, and the welds must be taken out in order to remove the valve assembly. Rewelding must then be performed in order to install the new valve assembly, a process which is labor-intensive and expensive.
As an alternative to complete replacement of the valve assembly, it is possible to repair the valve seat by rewelding the seat and machining it to the desired shape, or to simply remachine the valve without welding it first. However, the machining process cannot be accomplished in-line with conventional tools; it is necessary to take out the welds which interconnect the pipe and valve body, lift the valve body out of the line, and transport the valve to and from the machine shop or original equipment manufacturer. This process is very time-consuming and results in substantial shut-down time.
The present invention addresses these and many other problems associated with currently available methods and apparatus for replacing and repairing valve seats. | {
"pile_set_name": "USPTO Backgrounds"
} |
Rilpivirine hydrochloride, chemically 4-[[4-[[4-(2-cyanoethenyl)-2,6-dimethylphenyl]amino]pyrimidinyl]amino]benzonitrile hydrochloride and has the structural formula:
Rilpivirine (TMC278) is an investigational new drug, developed by Tibotec, for the treatment of HIV infection. It is a second-generation non-nucleoside reverse transcriptase inhibitor (NNRTI) with higher potency, longer half-life and reduced side-effect profile compared with older NNRTIs.
Rilpivirine and its hydrochloride salt were disclosed in U.S. Pat. No. 7,125,879.
Process for the preparation of rilpivirine was disclosed in U.S. Pat. No. 7,399,856 ('856 patent). According to the '856 patent, rilpivirine can be prepared by reacting the (E)-3-(4-amino-3,5-dimethylphenyl)acrylonitrile hydrochloride of formula II with 4-(4-chloropyrimidin-2-ylamino)benzonitrile of formula III-a in the presence of potassium carbonate and acetonitrile under reflux for 69 hours. The synthetic procedure is illustrated in scheme I, below:
According to the '856 patent, 4-(4-chloropyrimidin-2-ylamino)benzonitrile of formula III-a can be prepared by reacting the 4-[(1,4-dihydro-4-oxo-2-pyrimidinyl)amino]benzonitrile with phosphorus oxytrichloride in the presence of methylene chloride and 2-propanone.
Process for the preparation of rilpivirine was disclosed in U.S. Pat. No. 7,705,148 ('148 patent). According to the '148 patent, rilpivirine can be prepared by reacting the 4-[[4-[[4-bromo-2,6-dimethylphenyl]amino]-2-pyrimidinyl]amino]benzonitrile with acrylonitrile in the presence of palladium acetate, N,N-diethylethanamine and tris(2-methylphenyl)phosphine in acetonitrile.
According to the '148 patent, rilpivirine can be prepared by reacting the compound of formula IV with 4-(4-chloropyrimidin-2-ylamino)benzonitrile formula III-a in the presence of hydrochloric acid and n-propanol to obtain a compound of formula VII, and then the compound was treated with acetonitrile and potassium carbonate under reflux for 69 hours. The synthetic procedure is illustrated in scheme II, below:
According to the '148 patent, 4-(4-chloropyrimidin-2-ylamino)benzonitrile of formula III-a can be prepared by reacting the 4-[(1,4-dihydro-4-oxo-2-pyrimidinyl)amino]benzonitrile with phosphorus oxytrichloride in the presence of methylene chloride and 2-propanone.
U.S. Pat. No. 7,563,922 disclosed a process for the preparation of (E)-3-(4-amino-3,5-dimethylphenyl)acrylonitrile hydrochloride. According to the patent, (E)-3-(4-amino-3,5-dimethylphenyl)acrylonitrile hydrochloride can be prepared by reacting the 4-iodo-2,6-dimethyl-benzenamine in N,N-dimethylacetamide with acrylonitrile in the presence of sodium acetate and toluene, and then the solid thus obtained was reacted with hydrochloric acid in 2-propanol in the presence of ethanol and diisopropyl ether.
An unpublished application, IN 1415/CHE/2011 assigned to Hetero Research Foundation discloses a process for the preparation of rilpivirine. According to the application, rilpivirine can be prepared by reacting the 4-(4-chloropyrimidin-2-ylamino)benzonitrile with (E)-3-(4-amino-3,5-dimethylphenyl)acrylonitrile hydrochloride in the presence of p-toluene sulfonic acid monohydrate and 1,4-dioxane.
It has been found that the rilpivirine produced according to the prior art procedures involves higher number of chemical steps and results in low yields. According to the present invention rilpivirine can be obtained in higher yields and in fewer number of reaction steps than the prior art processes.
We have found a novel process for the preparation of rilpivirine and its pharmaceutically acceptable acid addition salts thereof using novel intermediate.
The process of present invention is simple, inexpensive and reproducible and is well suited on an industrial scale.
Thus, an object of the present invention is to provide a novel process for preparing rilpivirine and pharmaceutically acceptable acid addition salts thereof in high yields using novel intermediate. | {
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In application, the streamers are usually towed behind a vessel, either a ship or submarine. In active sensing, an acoustic noise source insonifies an area and the streamer detects reflections from any targets in the area. In passive sensing the streamer merely "listens" for any noise generated by targets. This invention describes techniques that may be applied to streamers used in either application.
An axial section of a prior art streamer structure is given in FIG. 1 and will be familiar to those skilled in the art. Connector 1 mechanically, electrically and optically connects each streamer section to the one before it and thence ultimately to the towing vessel. The signal from hydrophone 2 (only one hydrophone is shown) is taken to connector 1 via wires 3. Strength members 4 run from connector to connector and provide the axial mechanical strength. A core material, either solid or liquid, fills the space 5 to provide buoyancy (and in some cases desirable acoustic properties). The streamer section is enclosed with a continuous skin 6, which protects the in-streamer components from water ingress.
A critical performance criterion of streamers is the self noise of the streamer. That is, the unwanted acoustic signal that is detected by the hydrophones when the streamer is towed through the water. The self noise has two major components, that caused by the turbulence generated by towing the streamer through the water (flow noise) and that induced by the vibration of the streamer structure. A large part of the vibration coupled into the streamer originates from the tow vessel and is transmitted to the hydrophone section via the towing cable and strength members. Other sources of vibration may also be present, but are usually less important.
In liquid filled streamers the vibration noise is dominated by a single propagating wave and can be reduced by designing a group of hydrophones which are spaced in the direction of propagation, the spacing being a function of the wavelength of the propagating wave. The signals from the group of hydrophones are then summed into a single channel and the wave effects thus cancel each other. Although this technique is successful at noise reduction over a limited frequency range at the design temperature, the performance cannot be sustained for the temperature range over which the seismic streamer has to operate due to changes in the characteristics of the propagating wave. Typically the jacket material has to be changed to sustain the performance.
Hitherto, liquid filled streamers have been used since the liquid fill has been shown to have favourable properties with regard to self noise, but liquid filled streamers are fragile and can be inconvenient in operation. For example, damage to one section of the streamer during steady state towing can lead to a "knock-on effect" whereby all the sections fail progressively as the streamer sinks. Damage to a section of solid-filled streamer will not necessarily lead to failure of that particular section or any other section and, accordingly, solid-filled streamers are generally preferred.
Liquid filled streamers are also susceptible to damage during recovery and deployment which is normally achieved by winching. In order to minimise this damage streamers are recovered at low boat speeds and winching speeds. The low recovery speeds and susceptibility to damage during winching can lead to loss of valuable survey time with a consequent loss of revenue. This becomes more evident when data is being collected using multiple streamers. The use of solid streamers allows recovery at the normal operating speeds with loss of data only from the streamer being recovered. The recovery time is also reduced by winching at line speeds higher than that which can be achieved with liquid filled streamers.
Efforts at replacing liquid filled with more robust solid filled streamers have been frustrated by difficulties in reducing the self noise of solid streamers to acceptable levels.
In conventional streamer structures such as that shown in FIG. 1, vibration at the head of the streamer couples via the strength members 4 and connector plates 1 into the core material 5 of the streamer which is liquid. This then generates a slow speed bulge or breathing wave of high amplitude, compared with the acoustic signals normally received by the hydrophones, thus increasing the overall self noise of the streamer. If the core material 5 is solid the performance is usually worse, unless the carrier disclosed herein is incorporated. | {
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1. Field of the Invention
The present invention relates to product feed apparatus and associated equipment for the manufacture of food products.
2. Description of the Prior Art
The particular problem in the prior art which prompted development of the present product feed apparatus is the difficulty of automatically transferring a plurality of cookies from a single cookie holder to a plurality of conveyor lines for subsequent combination of the cookies with other cookies to form ice cream sandwiches. However, as will be seen the present invention is also adapted to handle products other than cookies.
Ice cream cookie sandwiches are very popular and a number of dairies of modest size compete for this market. Typically, dairy employees arrange cookies on large trays, perhaps four cookies wide, and operate an ice cream machine having feed spouts or nozzles to deposit a layer of ice cream on each of the cookies. Other employees then manually place other cookies on top of the ice cream layers to form the desired sandwiches, exercising care to make the overall height of the sandwiches uniform to fit within standard size packages. The operation is tedious and time-consuming and requires an inordinately high number of employees. In addition, the uniformity and quality of the finished ice cream sandwiches occasionally suffer because of the manual character of the operation.
More complex equipment is available to form ice cream sandwiches, but such equipment is quite expensive and is not adapted to handle round cookies. In addition, the size and consequent lack of mobility render the equipment unsuitable for the average small dairy or like user. Moreover, such equipment is usually characterized by a feed mechanism having a number of product holders corresponding to the number of conveyor lines involved. Stacks of the products are held in these holders adjacent the conveyor lines, respectively, and a number of transfer devices are employed to move the products from each holder to the adjacent conveyor line. The equipment attendants must thus exercise care to ensure that all of the holders are kept filled during operation of the equipment.
Aside from the deficiencies of the product feed apparatus of the prior art, there is also a need for a relatively simple and inexpensive machine for manufacturing ice cream sandwiches or the like, particularly round sandwiches, in a rapid, uniform, and reliable manner. | {
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The present invention relates to a folding collapsible jogging exerciser, and more particularly to such a folding collapsible jogging exerciser which enables the track unit to be maintained in a substantially horizontal position and closely attached to the ground.
FIG. 1 shows a folding collapsible jogging exerciser according to the prior art. This structure of folding collapsible jogging exerciser comprises a rack 13, and a track unit turned about a pivot axis 11 between a horizontal namely the operative position and a vertical namely the collapsed position. When the track unit is set in the operative (horizontal) position, the distance S between the pivot axis 11 and the front edge of the track unit must be smaller than the distance H between the floor and the bottom side wall of the track unit, so that the track unit can be turned about the pivot axis 11 between the horizontal position and the vertical position. However, because the distance H is greater than the distance S, the track unit is suspended above the floor at a height when set in the operative (horizontal) position. The user may feel uncomfortable and unsafe when running on the track of the track unit, which is suspended above the floor at a height. | {
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In EMG, the electrical activity of muscle tissue is recorded and interpreted. When a muscle fibre contracts, a potential is generated. Signals from a given muscle, or group of muscles, can be detected by use of an appropriately situated electrode. This is generally achieved by use of a needle probe having a conducting inner core fixed within a conducting outer cannula, the two being insulated from each other by an intervening insulating layer. The conductive parts of the needle are connected to separate pins of a plug for attachment to the recording equipment. Conventionally, this is achieved by use of separate connecting pins attached to the outer cannula and attached to the inner core, which generally consists of a metal wire.
During an EMG procedure, it is often necessary to use such a probe to take a number of measurements for a single patient. However, to reduce risk of infection to patients, it is desirable to dispose of a needle altogether after it has been used for one patient. This is an expensive procedure if conventional needle probes are used, as several manufacturing stages are required to produce the needle probe, which comprises not only a needle but also an electrical plug. It is thus desirable to provide a new design of needle probe in which new needles can be used for each patient without there being a need to replace an expensive part each time that this is done.
A potential line of development is to simplify the disposable part. This however poses difficulty, because of the need to provide reliable electrical connection between the plug of the probe and, separately, the inner core and the outer cannula. | {
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1. Field of the Invention
The present invention relates to a waterproof joint for wireharness, and in particular to a waterproof joint for improving waterproofness at a wire connecting portion of wires of the wireharness.
2. Description of the Prior Art
Conventionally, various types waterproof structures for use in a wire connecting portion of wires of wireharness (herein after referred to as "joint section") have been proposed, since if water enters the joint section of the wireharness there may be caused many problems such as heating of resistors and ill-conduction because of generation of rust, or the like.
FIGS. 1 to 3 show one of such conventional waterproof structures for a joint section of a wireharness. In this waterproof structure, the joint section 150 in which a branch electrical wire 130 is connected to a main electrical wire 100 is embedded in a synthetic resin by injection molding so as to prevent water from entering therein.
Specifically, as shown in FIG. 1, in this joint section 150, an exposed conductor 140 of the wire 130 which is formed by partially stripping an insulating cover of the wire 130 is connected through a joint metal 200 to an exposed conductor 120 of the main wire 100 which is also formed by partially stripping an insulating cover 110 of the wire 100. The thus formed joint section 150 which is constituted from a connecting portion of the conductors and a part of the insulating cover of each of wires connected together is put into injection mold dies 300 and 300' as shown in FIG. 2. Thereafter, a synthetic resin that is softened by heat is poured into the dies 300 and 300', and then cooled and hardened, so that the joint section 150 is embedded in the synthetic resin 400 to form a waterproof joint as shown in FIG. 3.
FIGS. 4(a) and (b) show another conventional waterproof joint structure, in which a joint section of a wireharness is covered with a sealing member 500. In this waterproof structure, a joint section 150 of the main wire 100 and the branch wire 130 of the wireharness is formed in the same manner as the above prior art. Thus formed joint section 150 is covered with the sealing member 500 which includes an insulating sheet 510 and viscous and elastic waterproof compound 520 applied inside the insulating seat 510 in such a manner that the viscous and elastic waterproof compound 520 is placed on the inner side of the sealing member 500 when it is attached to the joint section 150.
FIG. 5 shows yet another conventional waterproof joint structure. Such type of waterproof joint structure is, for example, disclosed in Japanese Laid-open Patent Publication No. 52-17686 or Japanese Laid-open Utility Model Publication No. 62-123072. In this conventional waterproof joint, a joint section which has the same structure as those of the conventional joint sections as described above is covered with a thermal shrinkable tube 600. The thermally shrinkable tube 600 comprises an elastic thermal plastic adhesive 700 such as a heat fusion seal material or a butyl rubber applied on the inner side of the heat shrinkable tube 600. When the thermally shrinkable tube 600 is heated, the thermal plastic adhesive 700 is melted and then penetrates around the joint section 150 and into gaps or spaces between the wires 100 and 130 to achieve a seal of the joint section 150.
However, in the first conventional waterproof joint, although a sealing ability thereof is good, it requires to prepare molding equipment such as molding dies and an injection molding apparatus, thus leading to high costs in manufacturing the waterproof joints. Further, in this waterproof joint, it is necessary to prepare different type mold dies according to the types or sizes of wires to be connected, thus leading to troublesome parts control for the waterproof joints. Furthermore, there is another problem in that many branch wires can not be connected to the main wire due to space limitations in the dies. Moreover, in this waterproof joint, since it was required to put the joint section at the center of the dies in order to give a good sealability to the joint section, it was also necessary to accurately position the joint section with respect to the dies. This positioning operation is also troublesome.
Further, in the second conventional waterproof joint, it is necessary for the insulating sheet 510 to be massaged manually in order to fill the viscous waterproof compound 520 into spaces between the cables 100 130 when it is attached to the joint section 150. This means that productivity of the waterproof joint is not so good and that there is a possibility that some spaces or gaps would remain around the joint section, which deteriorates the sealability, so that quality stability may also be deteriorated.
Furthermore, in the third conventional waterproof joint employing the thermally shrinkable tube, there is a problem that if the number of wires to be connected is increased, the thermal plastic adhesive may not completely penetrate into spaces between the wires, thus resulting in unfavourable spaces therein. Further, according to this waterproof joint, since the thermally shrinkable tube is likely to be displaced with respect to the joint section 150 before heat is applied, there is a possibility that a part of the joint section 150 would be exposed from the tube. Furthermore, when the thermally shrinkable tube is attached to the joint section, the positioning of the tube with respect to the joint section is performed visually by an operator. Therefore, there is an unfavourable possibility that the joint section 150 would not be entirely covered by the thermally shrinkable tube, thus leaving a part of the joint section exposed or that uneven distribution of the thermal plastic adhesive would be caused in the tube, thus leasing to deterioration of the waterproofness of the waterproof joint. | {
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This invention relates to attachments for securing snap fastener components to the exposed edge of a boat windshield.
Many pleasure boats in use today have windshields that project upwardly from the gunwales and front deck. Often the exposed edge of the windshield is covered with a protective resilient trim. Most pleasure boats also have removable covers to protect the boat when it is not in use or during inclement weather. These covers, typically formed of flexible material such as canvas, are fastened to the exposed edge of the windshield. To this end, attachments are placed at spaced locations along the exposed edge of the windshield. Each attachment carries a conventional snap fastener component that mates with a corresponding component that is affixed to the cover.
The windshield attachments bear significant stresses each time the cover is attached to, or removed from, the windshield. Furthermore, since most flexible covers are designed to fit tautly when fastened, the windshield attachments are usually under some stress when the cover is in place. Accordingly, windshield attachments must be configured to withstand these stresses to avoid breakage, while remaining securely attached to the windshield. | {
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It is known to construct tubular members for vehicles such as automotive vehicles. The tubular members are typically extruded from aluminum or magnesium and have a constant wall thickness. However, it is occasionally desirable to have a tubular member that has an increased stiffness, wherein the stiffness is increased away from the ends of the tubular member.
It is known to hydroform tubular components or members. Hydroformed tubular members are becoming increasingly popular in automotive body structural applications. During vehicle body manufacturing, many of the hydroformed tubular members are used in vehicle body and chassis applications. However, vehicle strength, stiffness, and/or impactworthiness often necessitate the need for local areas of structural reinforcement to meet their design goals.
It is further known to make “T” fittings such as for plumbing tube connectors using an axial feed hydroforming process. In this process, a die is constructed to have two opposing end seals and a piston situated in a center and perpendicular to the straight cylindrical cavity of the die. A straight tubular member is placed in the die. The die is closed and the ends seals are brought into contact with the ends of the tubular member. Fluid is filled into the tubular member. The hydroforming process proceeds by progressively increasing the internal fluid pressure in the tubular member while the end seals are pushed toward one another, compressing the tubular member axially. Concurrent with the end seals moving toward each other, the central piston, which was initially flush with the die cavity wall, is progressively retracted to allow a sidewall of the tubular member to bulge into a shaft of the piston and create a “T” shape of the T fitting. The resulting hydroformed dome of the T fitting will have a portion of its sidewall that is straight and of length in contact with the shaft of the central piston. However, there are circumstances in which the requirements for length of the straight side of the hydroformed dome of the “T” fitting is inadequate for sufficient overlap of an attaching tubular member to produce a reliable lap weld condition.
As a result, it is desirable to provide a method of increasing a straight sidewall of a dome on a T fitting. It is also desirable to provide a hydroformed “T” shaped tubular member having sufficient overlap for an attaching tubular member to produce a reliable lap weld condition. Therefore, there is a need in the art to provide a new hydroformed tubular member and cost effective method that meets at least one of these desires. | {
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1. Field of the Invention
This application relates to the drilling of wells in the production of oil, gas, and other fluids from underground formations, and particularly to the stabilization of boreholes drilled for the production of hydrocarbons. It includes the treatment of shale and clay in situ to prevent swelling caused by the absorption of water from drilling fluids.
2. Description of the Related Art
A good description of the problem which this invention addresses in the context of formation drilling may be found in an article by Thomas W. Beihoffer, et al. in the May 16, 1992 Oil & Gas Journal, page 47 et seq., entitled “Cationic Polymer Drilling Fluid Can Sometimes Replace Oil-based Mud.” As stated therein, “(S)hales can become unstable when they react with water in the drilling fluid. These reactive shales contain clays that have been dehydrated over geologic time by overburden pressure. When the formation is exposed, the clays osmotically imbibe water from the drilling fluid. This leads to swelling of the shale, induced stresses, loss of mechanical strength, and shale failure.” Shale crumbling into the borehole (“sloughing”) can ultimately place a burden on the drill bit which makes it impossible to retrieve.
Salts such as potassium chloride have been widely used in drilling treatments to convert the formation material from the sodium form by ion exchange to, for example, the potassium form which is less vulnerable to swelling. Also, the use of high concentrations of potassium salts affects the osmotic balance and tends to inhibit the flow of water away from the high potassium salt concentrations into the shale. However, it is difficult to maintain the required high concentrations of potassium salts in the drilling fluids. In addition, the physical introduction of such salts causes difficulties with the preparation of the viscosifying materials typically used for drilling. Inorganic salts can also have a harmful effect on the environment if released.
As background for the present disclosure, I have assembled prior art references representative of three general types of amine and quaternary ammonium cation sources which have been suggested for clay treatment in hydrocarbon recovery. These are (a) single-site quaternaries and amines, (b) compounds having a few (two to about six) amine or quaternary ammonium cation sites, which I have called “oligocationic”, and (c) quaternary ammonium or amine polymers, which may have from about six to thousands of cationic sites. The entire specifications of all of the patents set forth below are incorporated by reference, as the cationic materials described therein are useful in my invention.
A. Single-Site Quaternaries and Amines: Brown, U.S. Pat. No. 2,761,835; Brown, U.S. Pat. No. 2,761,840; Brown, U.S. Pat. No. 2,761,836; Himes, et al., U.S. Pat. No. 4,842,073; Thomas and Smith, U.S. Pat. No. 5,211,239.
B. Oligocationics: Brown, U.S. Pat. No. 2,761,843; Krieg, U.S. Pat. No. 3,349,032.
C. Polycationics: Borchardt, et al., U.S. Pat. No. 4,447,342; McLaughlin, et al., U.S. Pat. No. 4,374,739; McLaughlin, et al., U.S. Pat. No. 4,366,071. | {
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Plastic boards are common used in furniture manufacturing. The plastic boards can be used to make table top, chair seat and back, horizontal, perpendicular, clap board, drawer board of bookrack and cabinet, etc. Plastic boards are more and more common. Existing plastic boards used to make above products are manufactured by injecting, blowing and absorbing. For injecting, the plastic boards are limited, particularly for table top with large size, the manufacturing needs high-level equipments and the process is difficult. For blowing, although the blowing plastic boards have clean appearance and are easy to clean, the boards are thick, especially large size products, the production period is long and the production efficiency is low, large quantity of devices and dies are needed, the manufacturing process is complicated, making the cost high and influencing the product competitiveness. For absorbing, the plastic board is compositing by two or more plastic boards, leading to large dosage of plastic, moreover, the strength of this kind of the plastic board has some limitation. | {
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1. Field of the Invention
The present invention relates to a water base ink set for ink-jet recording to be used for an ink-jet recording apparatus, the ink-jet recording apparatus including the same, and an ink-jet recording method.
2. Related Art
The ink-jet recording system is a recording system that inks of several colors, which constitute basic colors, are converted into minute droplets of several picoliters to several tens of picoliters by using an ink discharge method including, for example, the bubble method in which the ink is discharged from a minute nozzle in accordance with the action of bubbles generated by rapid heating, and the piezoelectric method in which the ink is discharged from a minute nozzle in accordance with the action of a piezoelectric element that is deformable depending on an applied voltage so that the minute droplets are selectively landed on a paper surface to form an image thereby.
The ink-jet recording system is excellent in that it is possible to reproduce colors approximate to those of the full color and form an image having no granular texture by highly accurately controlling the discharge of minute droplets, making it possible to realize a high text printing quality and a high photographic printing quality. However, in order to discharge the minute droplets with such a high degree of accuracy, it is required to use a highly accurate landing control technique based on the use of a sufficiently thin discharge nozzle. Further, it is required to remove any dust and impurities from the ink. Therefore, it is necessary that the water base ink for ink-jet recording is subjected to precision filtration, and sufficiently washed materials are used for all parts which make contact with the ink.
Most of typical full color ink-jet printers, which use the ink set composed of four colors of black, yellow, magenta, and cyan, use the ink containing the anionic dye in view of the coloring performance on the paper and the toxicity. However, the ink containing the anionic dye is insufficient in vividness, for example, especially in the case of the yellow color. It is demanded to obtain a more vivid color. In order to satisfy such a demand, it is preferable to use the cationic dye which is used for a marker pen or the like and which has vivid color development performance. On the other hand, each of single colors of the inks containing the cationic dyes is vivid. However, if the inks containing the cationic dyes are used for all inks, it is hard to say that they are suitable in view of the balance of colors. Therefore, in order to obtain an image which is vivid and which is excellent in color balance, it is preferable to use the ink containing the anionic dye and the ink containing the cationic dye in combination.
However, if the ink containing the anionic dye and the ink containing the cationic dye are used in combination, it is feared that the inks may be mixed with each other at the head discharge portion, and any insoluble inorganic salt may be produced, or any deposit may be formed due to the deposition or precipitation of the dye, because the head discharge portions for the respective colors of the ink-jet printer are arranged closely on an identical plane, and an identical wiper is used for the head discharge portions for the respective colors in order to clean the head discharge portions. The amount of produced deposit differs depending on, for example, the type and the concentration of the dye and the type and the concentration of the solvent. However, when the deposit is formed, then any clog-up occurs at the head discharge portion, and it is impossible to highly accurately control the discharge landing.
An ink-jet recording apparatus, which has only a single head, is provided with a single ink tank (or an ink cartridge) as well. Therefore, such an ink-jet recording apparatus can use only unicolor ink in ordinary cases. When the ink contained in the ink tank is consumed, it is necessary that the empty ink tank is exchanged with another tank filled with an ink. For example, when an ink contained in the tank filled with the anionic dye ink is exhausted, an user intends to use a cationic dye ink next time in some cases. In such a situation, it is necessary that the ink container, which was filled with the anionic dye ink, is detached from the ink-jet head, and the ink container, which is filled with the cationic dye ink, is attached thereto. During this process, if any anionic dye ink remains in the ink-jet head, it is feared that the anionic dye ink may be mixed with the cationic dye ink allowed to inflow into the head, and any insoluble inorganic salt may be produced, or any deposit may be formed due to the deposition or precipitation of the dye. The amount of produced deposit differs depending on, for example, the type and the concentration of the dye and the type and the concentration of the solvent. However, when the deposit is produced, then any clog-up occurs at the head filter and the nozzle, and it is impossible to highly accurately control the discharge landing.
In the case of the conventional method, when the problem as described above occurs, it has been necessary to perform a treatment such that the ink (or the ink tank) is exchanged after substituting the interior of the head with a washing solution or the like so that the anionic dye ink and the cationic dye ink are not mixed with each other. However, such a procedure takes a long period of time. Further, another problem arises such that large amounts of the ink and the washing solution or the like are required.
The present invention has been made in order to solve the problems involved in the conventional technique as described above, a first object of which is to provide a water base ink set for ink-jet recording which makes it possible to perform stable discharge without any occurrence of clog-up at the head discharge portion and which makes it possible to perform vivid recording with high reliability, high accuracy, and good color balance even when an ink containing an anionic dye and an ink containing a cationic dye are used in combination, and an ink-jet recording apparatus which accommodates the ink set.
A second object of the present invention is to provide an ink-jet recording method which makes it possible to perform stable discharge without any occurrence of clog-up at the head filter and the nozzle and which makes it possible to perform highly reliable and highly accurate recording even when an anionic dye ink and a cationic dye ink are used in combination.
According to a first aspect of the present invention, there is provided a water base ink set for ink-jet recording comprising:
a first ink which contains an anionic dye; and
a second ink which contains a cationic dye, wherein:
at least one of the first and second inks contains at least two glycols selected from the group consisting of diethylene glycol, triethylene glycol, and polyethylene glycol, polyvinyl pyrrolidone, and water.
In the water base ink set for ink-jet recording, the first ink and the second ink may have different colors. The ink set may further comprise third and fourth inks. In this case, the first to fourth inks may have mutually different colors. For example, the second ink may have a yellow color, and the first ink may have a black, magenta, or cyan color.
In the water base ink set for ink-jet recording, the first ink and the second ink may have an identical color. In this case, an user can select the ink containing the anionic dye and the ink containing the cationic dye depending on the information to be recorded, for example, depending on the combination of colors. The water base ink set for ink-jet recording may further comprise a third ink which contains an anionic dye having a color different from that of the first ink, and a fourth ink which contains a cationic dye having the same color as that of the third ink, wherein at least one of the third and fourth inks contains at least two glycols selected from the group consisting of diethylene glycol, triethylene glycol, and polyethylene glycol, polyvinyl pyrrolidone, and water. For example, the ink set may comprise the inks containing the anionic dyes having four colors of black, yellow, magenta, and cyan, and the inks containing the cationic dyes having four colors of black, yellow, magenta, and cyan. In this case, an user can appropriately select the ink containing the anionic dye and the ink containing the cationic dye for each of the colors.
According to a second aspect of the present invention, there is provided an ink-jet recording apparatus comprising:
an ink-jet head which ejects an ink onto a recording medium;
a carriage which holds the ink-jet head and which is movable opposingly with respect to the recording medium; and
an water base ink set for ink-jet recording, wherein:
the ink set comprises a first ink which contains an anionic dye, and a second ink which contains a cationic dye, and at least one of the first and second inks contains at least two glycols selected from the group consisting of diethylene glycol, triethylene glycol, and polyethylene glycol, polyvinyl pyrrolidone, and water.
In the ink set and the ink-jet recording apparatus of the present invention, the ink set may be in a form of ink cartridge which is connectable to the ink-jet head and which is replaceable. The first ink and the second ink may have different colors. Alternatively, the first ink and the second ink may have an identical color. The ink cartridges may be independent containers for the respective inks. Alternatively, the ink cartridge may be one container provided with compartments for accommodating the inks of different colors, respectively.
According to a third aspect of the present invention, there is provided an ink-jet recording method for discharging an ink contained in an ink container onto a recording medium from an ink-jet head, the method comprising:
performing recording by connecting, to the ink-jet head, one of a first ink container filled with a first ink containing an anionic dye and a second ink container filled with a second ink containing a cationic dye; and
performing recording by connecting, to the ink-jet head, the other of the first and second ink containers in place of the one ink container, wherein:
at least one of the first and second inks contains at least two glycols selected from the group consisting of diethylene glycol, triethylene glycol, and polyethylene glycol, polyvinyl pyrrolidone, and water. According to the ink-jet recording method of the present invention, the first ink can be replaced with the second ink contained in the second ink container, depending on the situation to perform the recording or after the first ink is exhausted. During this process, it is unnecessary to wash the ink flow passage in the head. The first ink and the second ink may have different colors. Alternatively, the first ink and the second ink may have an identical color. | {
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The invention relates to sensor systems and, more particularly, to non-imaging, scanning sensor systems which simultaneously correct sensor output signal distortion caused by random sensor noise and temporal instabilities in the sensor scanning mechanism.
Non-imaging, scanning sensor systems are employed in many applications where it is desired to detect the presence of objects. For example, non-imaging scanning sensor systems employing an array of infrared detector elements positioned in a focal plane of a scanning optical system are used to passively detect the presence of objects at extended distances. The array is typically mounted on a gimballed sensor unit to scan a portion of a field of view and produce sensor output signals which are sampled and multiplexed for further processing by on-gimbal and off-gimbal circuitry.
Sensor output signals from the gimballed sensor unit can be degraded by distortion from a number of sources. Two of the largest and most common sources of sensor output signal distortion are timing, or temporal, instabilities in the sensor scanning mechanism, and random noise inherent in the sensor.
Temporal instabilities can arise in the output signal of scanning system sensor units from environmental stresses which induce undesired spatial displacement in the sensor scanning mechanism. Uncompensated spatial displacements can interrupt the linear scanning process of the scanning mechanism in the sensor unit. These discontinuities in the otherwise linear scanning process then cause temporal instabilities in the sensor output signal. Similarly, timing errors in the sampling circuitry of the sensor unit cause temporal instabilities in the sensor output signal. As a result, the actual view angle (.theta.) for the sensor unit can be expressed by: EQU .theta.(t)=kt+.DELTA.(t), (Eq. 1)
where k is a desired linear scan rate, and .DELTA. is a jitter angle error component measured as a function of time, t.
Conventional signal processing typically employs one of two methods to derive a desired linear representation of the output signal provided by the sensor unit when it scans an actual (nonlinear) view angle. The two compensation methods use phase shifting of Fast Fourier Transforms (FFT) frequency components and interpolation between signal samples, respectively, to, in effect, remove the jitter angle error component .DELTA.(t) from equation 1.
The method of phase shifting FFT frequency components is very complex. Actual signal samples are grouped into short "blocks" and processed through an FFT processor. The resulting FFT frequency components are phase rotated by a phase angle proportional to the product of the prevailing jitter angle and the FFT frequency component. After phase shifting has been applied to each FFT frequency component, an inverse FFT is performed to produce a desired "linear scan rate" representation of the sensor output signal.
This method, however, cannot compensate for rapidly changing jitter angle values, and the process of grouping the signal samples into blocks produces undesired "end-effects" which are difficult to accommodate. Accordingly, the method of phase shifting FFT frequency components is not practical in many scanning system applications.
Time interpolation between signal samples is a less complex method of compensating for temporal signal distortion and is adaptable to a greater range of scanning system applications. In this method, the actual sensor view angle is again denoted by: EQU .theta.(t)=kt+.DELTA.(t), and (Eq. 1)
a desired linear view angle is denoted by: EQU .theta.'(t)=kt, (Eq. 2)
for a scanning system with a sensor output signal sampled at a constant rate to produce signal samples S(t). For each desired linear view angle .theta.', the two closest actual view angles are determined, e.g., (.theta.'-a) which occurred at time t.sub.n and (.theta.'+b) which occurred at time t.sub.n+1.
The compensated signal sample output for the desired linear view 8, is computed by two-point linear interpolation as shown below: EQU S'=S(t.sub.n)+(1-X) S(t.sub.n+1) (Eq. 3)
where S' is a desired signal sample corresponding to .theta.', and X is the degree of interpolation defined as X=b (a+b) for coefficients a and b discussed above.
This particular computation method of interpolation is satisfactory for processing conditions where the observed signal amplitude varies linearly with time, but yields poor results when the observed si9nal varies nonlinearly with time. To partially overcome this limitation, the interpolation process has been extended to include parabolic (or higher order) smoothing between three (or more) sample values. However, poor results remain for conditions where the observed signal amplitude is a highly nonlinear function of time.
An exemplary conventional circuit for performing interpolation is shown in FIG. 1. Data samples V.sub.i are taken, for example, from a sensor output signal at a sampling rate sufficient to satisfactorily depict regions of nonlinear variation in the sampled signal waveform. The number of data samples selected for interpolation is kept low, e.g. 2, to reduce circuit complexity, and because interpolation between greater than four data samples is usually ineffective. Data samples V.sub.i are sequentially received and shifted through locations 101, 103, 105, and 107 of data memory 100. Multiple sets of coefficients, according to the degree of interpolation required, are selected and stored in a coefficient register 120. Each set of coefficients contains N coefficients per set. For example, for linear interpolation between two data samples, N will equal 2, and the coefficients are computed as X and 1-X, where X is the degree of interpolation desired. In other cases, N is made equal to 4 and coefficients are calculated to yield quadratic smoothing over four data samples. Higher order smoothing requires N to be even higher.
If the degree of interpolation required is constant, the set of coefficients is also constant. However, if the degree of required interpolation changes with time, the selected set of coefficients is made to change with time. This change is typically accomplished by shifting the coefficient register 120 to the left or right according to the change in the degree of interpolation.
The data samples, V.sub.1, V.sub.2, V.sub.3, V.sub.i shifted into data memory locations 101, 103, 105, 107 are multiplied by coefficients selected from coefficient register 120 in multipliers 131, 133, 135, 137, respectively. The resulting multiplicative results are then summed in summer 140 to form an interpolation output.
This method, referred to here as "dancing" interpolation does not, however, work as well as desired. Perfect interpolation would provide a frequency transfer function of: EQU 1.0 e .sup.(j2.pi.XfT) (Eq. 4)
where X is the degree of interpolation, f is the frequency of the input signal and T is the sample period. The results of this transfer function would leave the amplitude of a frequency component unchanged while shifting its phase by (.beta.=2.pi.XfT). In contrast, the two point linear interpolation method (N=2) discussed above provides an amplitude gain of EQU [X.sup.2 +(1-X).sup.2 +2X(1-X) cos .beta.]1/2
and a phase shift of ##EQU1## Other interpolation methods also fail to provide the desired frequency transfer function.
In addition to distortion caused by temporal instabilities in the sensor scanning unit, sensor output signals are degraded with random noise. To suppress this noise and thereby better define the desired sensor output signal waveform, data samples V.sub.i are typically processed through a conventional convolution filter.
An exemplary circuit of a conventional sampled data convolution filter is shown in FIG. 2. Data samples V.sub.i are sequentially received and shifted through data memory 200. In operation, data samples V.sub.1, V.sub.2, V.sub.3 ... V.sub.i stored in data memory locations 201, 203, 205, 207 are multiplied by corresponding weighting coefficients W.sub.1, W.sub.2, W.sub.3 ... W.sub.n stored in coefficient memory locations 221, 223, 225, 227 in respective multipliers 231, 233, 235 237. The resulting multiplicative results are then summed in summer 240 to provide the convolution filter output.
Conventional convolution filters perform weighting and summing operations on successive input data samples to produce filtered replicas, y(n), of the input data samples, generally defined by the equation ##EQU2## The factors a.sub.i and b.sub.i are weighting coefficients applied to delayed input and output samples V(n-i) and y(n-i), respectively, where i connotes the number of sample delay periods. Equation 5 defines the transfer function of a recursive filter. If the rightmost term of the equation is eliminated, the equation defines the transfer function of a non-recursive filter herein called a convolution filter.
The convolution filter of FIG. 2 is known to suppress the random noise component of an input waveform and thereby produce a reduced noise output waveform. It will be readily appreciated that the transfer function of the convolution filter of FIG. 2 can be altered by changing the values of the weighting coefficients W.sub.n, which correspond to a.sub.i in equation 5. In convolution filters, the time phase of a frequency component in the output waveform is related, in a known way, to the time phase of that frequency component in the input waveform. In other words, the output waveform is deterministically related to the input waveform and, so long as the sample rate satisfies the Nyquist theorem, this relationship is independent of the phasing of data samples taken from the input waveform.
For sensor output signals containing distortion caused by temporal instabilities and random noise, conventional signal processing methods require the sensor output signal to serially pass through interpolation and convolution filtering circuits, as shown in FIG. 3. Such a cascade of circuits, however, realizes imperfect interpolation and substantially increases overall circuit complexity.
In light of the foregoing discussion, it is desirable to provide a scanning sensor apparatus and method incorporating a system which simultaneously compensates for sensor output signal distortion produced by temporal instabilities and suppresses random sensor noise. It is further desirable to provide a method whereby improved interpolation of the sensor output signal is achieved when performed integral to a sampled-data convolution filter process. Additionally, it is desirable to provide an apparatus which is more convenient to implement and which provides improved jitter compensation for all spatial frequencies despite the presences of a rapidly changing jitter error angle.
Additional advantages of the invention will be set forth in part in the description which follows and in part will be obvious from the description, or may be learned by practice of the invention. The invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims. | {
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The use of cryptographic keys involves trust. When A encrypts data with B's key, A expects that only B will be able to decrypt the data. And when A verifies a signature that was created with B's key, A expects the existence of a valid signature to mean that B actually signed the data over which the signature was calculated. Therefore, when A uses B's key, it is legitimate for A to want to know how A can be sure that B's key really belongs to B, and how can A be sure that B's key has not been compromised.
Trust in keys is generally established through certificates. When an entity creates a key, the entity submits the key to an authority for certification. The authority determines whether the key and its owner meet the authority's standards for certification. If so, the authority issues a certificate for the key, which contains the key signed by the authority. Authorities are entities that are known to the community that they serve, and that the community trusts to certify the keys of other entities. If a recognized authority certifies a key, then the community that trusts the authority will trust the certified key. For example, browsers periodically receive updated lists of authorities, and the browsers will trust certificates issued by authorities on the list. An organization (e.g., a company) may have a certificate authority that is recognized and trusted by machines within that organization.
A trusted platform module (TPM) is a piece of hardware that can be used to provide various forms of security for a machine. One thing that a TPM can do is maintain hardware security around a key, thereby providing a high measure of assurance that the key will not be misused. In some cases, a certificate authority may be willing to certify only a key that is bound to a particular TPM, since this binding ensures that the key will only be used on the machine that contains that particular TPM. Therefore, in order to certify such a key, the certificate authority has to verify that the key is actually bound to the TPM on a particular machine, and cannot be migrated to other machines. Normally, the process of certifying such a key involves several round-trip exchanges between the certificate authority and the client that is requesting to have the key certified. When a client wants to certify a new non-migratable key that is secured by the client's TPM, the client requests that the TPM create a key called an Attestation Identity Key (AIK) for the new key. The client then asks the certificate authority to certify the AIK, which the certificate authority does after verifying that the AIK was actually generated by the TPM on the client's machine. The client then asks the TPM to sign the new key with the AIK, which the TPM will only do if the key is non-migratable. The client then submits the new key and the AIK-generated signature to the certificate authority. The certificate authority trusts the TPM, and has certified the AIK as belonging to the TPM. Therefore, the certificate authority will trust that the new key is non-migratable based on the TPM's having signed it with the AIK, so the certificate authority will issue a certificate for the new key.
A problem with this process, however, is that it involved multiple round trips between the client and the certificate authority: one trip to certify AIK, and another to certify the new key that the client is trying to certify. | {
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The 3GPP LTE (3rd Generation Partnership Project Long Term Evolution) is a project for improving the UMTS (Universal Mobile Telecommunication System)-standard, in order to cope with future requirements in terms of improved services, such as higher data rates, improved efficiency, and lower costs. The radio access network of an LTE system is commonly referred to as an E-UTRAN (Evolved Universal Terrestrial Radio Access Network), and the UTRAN is the radio access network according to the UMTS.
In a UTRAN, a user equipment, UE, is connected to a radio base station commonly referred to as a Node B, and the Node B is connected to a network node, typically an RNC (Radio Network Controller). The RNC is connected to a core network, which comprises both a circuit switched service domain and a packet switched service domain.
In a radio access network according to the 2nd generation, e.g. a GERAN (Global System for Mobile communication, GSM, Edge Radio Access Network), the radio base station is referred to as a BTS (Base Transceiver Station), which is connected to a core network via a network node, typically a Base Station Controller (BSC), the core network also comprising both a circuit switched service domain and a packet switched service domain.
However, in the above-mentioned E-UTRAN, a UE is connected to a radio base station commonly referred to as an eNodeB (evolved NodeB), which is connected to the core network node, and the core network comprises only a packet switched service domain.
Thus, the E-UTRAN in the LTE uses a RAT (Radio Access Technology) that is not CS (Circuit Switched) capable. Instead, CS-based services, e.g. conventional circuit-switched voice calls, is replaced e.g. by VoIP in and LTE system.
For this reason, an LTE-capable UE that is attached to an E-UTRAN and wishes to initiate a CS service, e.g. a conventional voice call, has to transfer to a radio access network, RAN, with a CS-capable radio access technology, RAT, e.g. a UTRAN or a GERAN. Thus, the serving eNodeB will transfer the UE to a CS-capable radio access network in which the UE has radio coverage, and this RAN will provide the requested CS-service to the UE.
FIG. 1 schematically illustrates an UE 11 having an overlapping UTRA-radio coverage and E-UTRA-radio coverage. The figure shows a NodeB 14 of a UTRAN and an eNodeB 15 of an E-UTRAN. The NodeB 14 is connected to a network node of the UTRAN, i.e. an RNC 16, and the eNodeB is connected to a core network node 18. The UE 11 is located within an overlapping area of the UTRAN cell 12 and the E-UTRAN cell 13, wherein the UE may transfer from the E-UTRAN to the UTRAN, when it requests a CS service.
The transfer of the UE to the UTRAN due to the UE requesting a CS service could be performed e.g. according to a standardized CSFB (Circuit Switched Fall Back)-mechanism, which uses a PS HO (Packet Switched Hand Over) or a RRC Release operation. However, no specific mechanism is standardized for transferring the UE back to E-UTRAN after a CSFB, when the CS service has ended. Instead, when the CS service is terminated, and no PS (Packet Switched) session is ongoing, the UE is expected to go to Idle mode, and return to the E-UTRAN using e.g. a standardized LTE Cell Reselection. The Cell Reselection can also take place if the UE is in a CELL_PCH-state or in a URA_PCH-state, but not in a CELL_FACH-state.
Besides from the above-described situation, in which an LTE capable UE is connected to an UTRAN because a requested CS service is not available in E-UTRAN, other situations may exist in which an LTE capable UE may be connected to a UTRAN instead of to an E-UTRAN, such as e.g. when the UE does not have any LTE coverage, or due to operator strategies or load issues in the LTE network. However, when the reason for the connection to the UTRAN is not valid anymore, the UE should normally return to E-UTRAN as soon as possible.
Various methods exist for transferring a UE between two radio access network with different radio access technologies, such as e.g. from UTRAN to E-UTRAN, and different methods may apply for different UE states. The conventional method for a UE to transfer from a non-preferred RAT to the preferred RAT, in case the UE is in Idle mode or is connected on a common channel, is the above-mentioned LTE Cell Reselection, which requires that the UE is in the Idle mode, in a URA_PCH state or in a CELL_PCH state, i.e. that the UE has stopped transmitting data over the air, since the UE at this point is free to search for the most suitable available cell, with the highest prioritized radio access technology.
There is a need to improve handover between UTRAN and E-UTRAN. | {
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Numerous wood products in use today, such as fence posts, railroad ties, and dimensional lumber are dependent upon diminishing forest reserves as a source of material. For numerous applications, wood products are especially vulnerable to rot and decay from excessive exposure to moisture, insects, dry-rot and other conditions that cause deterioration to the product. Wood products must be coated with preservatives of various types when they are to be exposed to the environment. For example, railroad ties and fence posts have long been treated with creosote under pressure to protect the wood from moisture and boring insects. Special treatments and application of protective coatings of paints and oil add appreciably to the cost of wood materials, and none are known to offer indefinite protection. The use of petroleum based preservatives tend to add some pollution to the environment.
Products have been made utilizing waste materials such as old automobile tires, waste plastics, and resinous thermoplastic materials. Products made from these materials are made utilizing heat and pressure to extrude products. Examples of such processes are defined in U.S. Pat. Nos. 4,028,288 and 4,191,522. The heat and extrusion process usually involves temperature in excess of 450 degrees Fahrenheit. This presents problems when the waste products include polyvinyl Chloride (PVC). PVC materials are volatile, explode, and produce gases when exposed to heat at elevated temperatures. Even small amounts of PVC, as small as one percent, can be disastrous. Since it is difficult to separate PVC materials from waste recycled materials, extruding products from recycled material is not desirable. | {
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1. Field of the Invention
The present invention relates to an image signal processing apparatus and an image display each having a function of detecting a black band region included in an image signal, and an image display method performing such a black band detecting process.
2. Description of the Related Art
Image displays such as television receivers (TVs) typically have an image processing function which makes image quality correction to an input image (for example, functions such as luminance or contrast control, and contour correction). Such an image processing function is performed by acquiring, for example, the average peak level (APL) of an input image signal or the histogram distribution of a luminance level, and is effectively applied, because gradation is improved by preventing an image from appearing too dark or preventing poor reproduction of black.
Among image signals from DVDs containing Cinemascope size images or image signals transmitted from broadcast stations, there are a signal called a letterbox including black band regions above and below an image region, and a signal called a side panel including black band regions on the right and the left of an image region. When the above-described image processing is performed on such an image signal including the black band regions, the image processing is performed also on the black band regions which are independent of the contents of the image region, so image quality is not appropriately corrected, and the effect of the image processing is reduced.
Therefore, to effectively detect a black band region included in an input image signal in such a manner, various methods are proposed (for example, refer to Japanese Patent No. 3429842 and Japanese Unexamined Patent Application Publication Nos. H05-27736 and 2005-203933. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to battery charging and transfer systems. More particularly, the present invention relates to battery charging and transfer systems which enable the automated exchange and charging of electric vehicle batteries, including batteries for automobiles, motorscooters and other electrically powered motor vehicles.
U.S. Pat. No. 4,334,819 discloses a continuous battery charging system wherein batteries are removed from an electrical vehicle at a battery transfer station. A fresh battery is installed at the transfer station, and the spent battery is placed in a charging system to be charged and returned to the transfer station.
That system contemplates the existence of a need for capability to charge a large number of exchangeable batteries, say, following adoption and acceptance by the motoring public of the concept of electric powered vehicles. One disadvantage of electric powered vehicles is the relatively short range that can be achieved using known battery technology. In order to provide a practical electric vehicle system, battery transfer capabilities must exist at numerous locations, so that the range of travel, without requiring the driver to recharge a battery, may be substantial. This is to say that if the range of an electric vehicle, without recharge of the battery or battery pack is 100 miles, then the user is limited to excursions of 50 miles. However, if at 75 or 100 mile intervals, the user can conveniently replace the partially spent battery with a fresh or fully charged battery, the limit of safe travel is extended.
Thus, the prior patent discloses an invention which enables longer range use of electric vehicles, because charged or fresh batteries can be expeditiously installed in the vehicle at locations along a course of a length greater than the round trip capability of the vehicle battery. Notwithstanding the foregoing, there remains a need for an electric battery charging and transfer system which enables the convenient removal of discharged batteries from a vehicle and replacement with a fully charged battery. The batteries and the charging system must be adapted to efficiently handle the battery during the removal, charging, and installation procedures. | {
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Field of the Invention
The invention relates to a method of producing three-dimensional, selectively metallized parts, and three-dimensional, selectively metallized part.
The metallization of plastics using the electrodeposition technique enables the product to be completely metallized without additional measures. However, for most applications only partial metallization of the product is desired. There are various options for selective metallization. For example, a product can be injection-molded in two steps using two different plastics (two-component injection molding), in which case one plastic is metallizable and the other plastic is not metallizable. In that case, first of all a part is injection-molded from one plastic, and the part is then placed into a mold and completed by the injection molding of the other plastic. If the product is then metallized using a specific method, one plastic is metallized and the other is not metallized. Selective metallization can also be achieved by using light-sensitive resists. In this case, the entire product is initially provided with a thin, conductive metal layer by means of a chemical process. Then, a photoresist is applied and a pattern is produced in the resist by selective exposure and development. This pattern is reinforced by electrodeposition, and the photoresist can then be removed. It is now possible to remove the initial layer in an etching process, so that what remains is the pattern which has been grown on. A further possibility for selective metallization is made possible by the use of lasers. In that case, after metallization of the entire surface, the undesired metal layers can be removed locally by laser ablation (see, Report on the 15th Ulm Meeting on May 6 and 7, 1993 in Neu-Ulm, Eugen G. Leuze Verlag, Saulgau, pages 114-20, A. F. P. M. van Veggel xe2x80x9cHaftfeste Metallisierung von technischen Kunststoffenxe2x80x9d [Strongly adhering metallization of industrial plastics]).
In a variant of the production of selectively metallized products by two-component injection molding, a first core-catalyzed plastic and a second non-core-catalyzed plastic are used. The fact that the seeds have already been admixed with the first plastic means that in this case there is no need for wet chemical seeding of the injection-molded part. The subsequent metallization in a chemical metal deposition bath then results in selective deposition of metal in those regions which consist of the core-catalyzed plastic.
It is accordingly an object of the invention to provide a selectively metallized three-dimensional part and a production method, which overcome the above-mentioned disadvantages of the heretofore-known devices and methods of this general type and which allows simple and economical selective metallization of the three-dimensional parts.
With the foregoing and other objects in view there is provided, in accordance with the invention, a method of producing three-dimensional, selectively metallized parts from electrically insulating material, which comprises the following method steps:
producing three-dimensional parts by two-component injection molding, the parts having first regions to be metallized formed of a first plastic and second regions that are not to be metallized formed of a second plastic;
seeding an entire surface of the part;
selectively removing the seeding in the second regions that are not to be metallized aided by a solvent in which the first plastic is at least substantially insoluble and in which the second plastic is at least substantially soluble; and
depositing metal by electroless metal deposition in the first regions that are to be metallized.
The invention is based on the discovery that seeding of the entire surface of parts produced by two-component injection molding can be selectively removed by a solvent. This solvent must not attack the first plastic used in the regions which are to be metallized while it should readily dissolve the second plastic used in the regions which are not to be metallized, so that the seeding is selectively removed again in these regions. Then, subsequent electroless deposition of metal results in selective metallization of the regions which consist of the first plastic, since seeding is still present in those regions.
In accordance with an added feature of the invention, the electrolessly deposited metal layers are reinforced by electrodeposition. Reinforced metallization of this nature is particularly expedient for conductor patterns.
In accordance with an additional feature of the invention, seeding in a palladium system allows particularly effectively catalyzed electroless metal deposition in the regions which are to be metallized.
In accordance with another feature of the invention, the seeding is selectively removed using lye solution as the solvent. In this case, the fact that a first group of plastics is resistant to lye while a second group of plastics is soluble in lye is exploited. According to further refinements, PA and PS are preferably used as the first plastic which is resistant to lye. Similarly, LCP, PEI, PET, and PBT are good candidates for the second plastic, which is soluble in lye. Solvents based on KOH or NaOH are preferably used for the selective removal of the seeding. It is thereby possible to use pure KOH and pure NaOH, as well as mixtures of solvents which contain KOH or NaOH as the crucial component.
In accordance with a further feature of the invention, the seeding is selectively removed with acid as the solvent. In this case, the fact that a first group of plastics is resistant to acid while a second group of plastics is soluble in acid is exploited. In a preferred group, LCP, PEI, PET or PBT is preferably used as the first plastic, which is resistant to acid. Similarly, PA or PS is preferably used as the second plastic, which is soluble in acid. Furthermore, solvents based on HCl or H2SO4 or mixtures of C3O3 and H2SO4 or mixtures of CCl3xe2x80x94COOH and H2SO4 are preferably used for the selective removal of the seeding. It is thereby possible to use substantially pure HCl or pure H2SO4, or solvent mixtures which contain HCl or H2SO4 as the crucial components.
With the above and other objects in view there is also provided, in accordance with the invention, a three-dimensional, selectively metallized part which in the metallized regions consists of a first plastic and in the non-metallized regions consists of a second plastic. The first and second plastics have particular properties which are defined by the solubility in a predetermined solvent. The first plastic is at least substantially insoluble in a predetermined, specific solvent, while the second plastic is at least substantially soluble in the same solvent. For example, the first plastic is able to withstand lye, while the second plastic is soluble in lye. However, the first plastic may also be able to withstand acid while the second plastic is soluble in acid. These materials properties allow selective removal of seeding in lye or in acid during the production of the three-dimensional, selectively metallized parts.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a process for producing three-dimensional, selectively metallized parts, and three-dimensional, selectively metallized part, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. | {
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Not Applicable
Not Applicable
Communications systems using phase shift keying (PSK) modulation schemes are known. Such systems use the phase of a transmitted/received signal to transmit/receive intelligent data. The transmitted/received signal can be represented as a series of data vectors originating at the origin and having end points at data point values on a circle of an orthogonal system. Each data vector, accordingly, has an in phase component, known as the I coordinate or value of the data vector, and a quadrature component, known as the Q coordinate or value of the data vector. The transmissions from the transmitter of the communications system to a receiver of the communications system are often in the form of bursts of data, particularly in point-to-multipoint communications systems.
A PSK system in which data is represented by n points or vectors on the circle is known as an nPSK system. In nPSK systems there are xe2x80x9cnxe2x80x9d number of (usually equally spaced) data points along the vector circle, each point representing transmitted/received data. I and Q vectors change their relation with each other to control the data sent in nPSK systems. The relationship is referred to as a rotation of the composite phase vector V in an I and Q orthogonal system. This relationship is depicted in FIG. 1.
In QPSK (Quadrature Phase Shift Keying) systems, four data points are used. The I and Q vectors form xe2x80x9csymbolsxe2x80x9d of information, each symbol being one of the four digital states represented by the I and Q vectors, taken as 2 bits and relating to the four points seen on the circle of FIG. 1 and labeled 00, 01, 10, 11. QPSK systems offer an advantage in that the data points are few in number. As such, any phase error in the QPSK receiver causing the vector V to improperly move from position V to V1 of FIG. 1 will have to be substantial before the receiver has difficulty resolving whether it is the data point representing, for example, data state 00 of vector V1 or the data point representing data state 01 of vector V2. This phase error is most often caused by slips and shifts in time of the I and Q at the beginning and ending edges of a symbol period. These slips and shifts are frequently a function of phase errors between the received signal after it has been down converted to an intermediate frequency, IF, and the IF signal used to demodulate the QPSK symbols.
Referring to FIG. 2, there is shown the I and Q signals represented by lines 20 and 25 of a received signal that has been down converted to an intermediate frequency. As shown, the I and Q signals change states in accordance with the data transmitted during each symbol period. As such, the received sinusoidal IF that was used to develop the I (line 20) and the Q (line 25) envelope depicted by line 30, unless it is absolutely phased to the signal used in the modulation of the I and Q signal, will have inaccuracies during the times designated at E and F. This inaccuracy in the envelope will cause phase errors. The higher the ratio between the IF frequency and the I and Q signal transition frequencies, the better the resolution and hence less phase error.
One manner of synthesizing the signal used to demodulate the I and Q signals is to synthesize the demodulating signal using direct digital synthesis (DDS) of the entire IF waveform, keeping the received IF signal and synthesized demodulating signal completely in phase at all times. The present inventors, however, have recognized that such DDS schemes are often quite complicated and costly to implement. As such, they have set forth an nPSK burst communications system and receiver architecture which is less costly to implement than its DDS counterpart while still being highly reliable and accurate. Additionally, the inventors have set forth a clock generator/data decoding circuit that improves the integrity of the received data.
An nPSK communications system is set forth. The communications system includes a transmitter for transmitting phase shift key modulated burst signals, including I and Q components, on a transmission medium. The burst signals include a prefix portion and a data portion. The I and Q components of the prefix portion are maintained at a predetermined relationship during at least a portion of the prefix portion. The communications system also includes a receiver for receiving the phase shift key modulated burst signals from the transmission medium. The receiver includes an IF section for mixing received burst signals to an intermediate frequency signal, the intermediate frequency signal having a phase. The receiver further includes an I-Q demodulator that comprises a demodulator frequency generator for generating a demodulating signal having a frequency equal to or an integer multiple of the intermediate frequency signal to thereby extract the I and Q components of the received burst signals. A phase adjustment circuit, responsive to the I and Q components that are maintained at the predetermined relationship, is used for adjusting the phase of the demodulating signal so that it is substantially in phase with the intermediate frequency signal.
In accordance with a further aspect of the disclosed invention, a receiver for receiving phase shift key modulated signals that are transmitted at a symbol rate in which a circuit for determining the respective states of baseband I and Q signals of the phase shift key modulated signals is set forth. The circuit comprises a transition detector for detecting a state transition of at least one of the baseband I and Q signals and for generating a state transition signal in response to the state transition. A peak detector circuit detects the occurrence of the peak amplitude of at least one of the baseband I and Q signals and generates a peak detected signal in response to occurrence of the peak amplitude. A clock generator circuit generates the symbol clock signal at the symbol rate in response to the state transition signal and the peak detected signal to adjust the phase of the symbol clock signal. An analog-to-digital converter samples each of the baseband I and Q component signals at a predetermined rate to generate a first digital sample output stream from the baseband I component and a second digital sample output stream from the baseband Q component. Each digital data sample of the first digital sample output stream is indicative of a logic state of the baseband I component at a respective sample time and each digital data sample of the second digital sample output stream is indicative of a logic state of the baseband Q component at a respective sample time. The predetermined rate is at least twice the Nyquist frequency of the baseband I and Q component signals. A voter circuit receives the first and second digital data sample streams, and, in response to occurrence of the symbol clock signal, compares a current digital data sample of the first digital data sample output stream to prior and subsequent digital data samples of the first digital data sample output stream to provide an I state signal output and, in response to occurrence of the symbol clock signal, compares a current digital data sample of the second digital data sample output stream to prior and subsequent digital data samples of the second digital data sample output stream to provide a Q state signal output. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to packet transmission in multiple access communication systems.
In this patent document, the references referred to in square brackets, eg [1], are listed at the end of the disclosure.
The 3G CDMA system is supposed to support simultaneous voice/packet data/circuit data operations [1] with different QoS requirements. Since the traffic characteristics and the quality of service requirements for packet data services are quite different from those of voice traffic, system re-design in certain essential aspects is necessary for an integrated voice-data system without impacting voice quality or sacrificing data performance.
Packet-type services are designed for on-off sources, which generate no information during often prolonged, but unpredictable, off intervals. For many data applications the intermittent nature of the traffic is orders of magnitude greater than that of voice signals as shown in FIG. 1. The system capacity can be greatly increased if no signal is transmitted during the off period, since the CDMA system is interference limited.
The efficient provision of packet-type services is particularly difficult on reverse links (from mobile to base station) of CDMA systems, because of the need to rapidly regain synchronization of spreading sequences when the source resumes transmission after a period of silence. One possible solution to the link maintenance problem when bursty transmission is required on reverse links of CDMA systems is to assign a separate low bit rate physical control channel (created using code division multiplex) to each portable in a given cell. This approach, proposed by some investigators [2], can be called a continuous transmission medium access control scheme (CTX-MAC), and it unfortunately causes increased multi-user interference introduced by continuously transmitted maintenance signals. Increased interference naturally leads to reduced traffic capacity. Also its implementation is characterized by significantly increased complexity of base station receivers, where each physical control channel (serving one portable) would require a separate despreading correlator. If the duty cycle (ratio of the on-period to off-period of the mobile""s transmitter) as shown in FIG. 1 is small, then considerable savings in both base station hardware and system capacity may be achieved if transmission is discontinued during the off-periods and the hardware is shared among different users. This is the discontinuous transmission medium access control (DTX-MAC) scheme. With the DTX-MAC scheme, when a particular user has a data packet to send, the base station needs to be notified by the mobile of its intention to transmit, and synchronization needs to be quickly resumed. To achieve that an access request message (ARM) is transmitted from the mobile to base station to acquire synchronism, and to inform the base station of the mobile""s identity. An access reservation channel (ARC) is allocated for such a purpose. All mobiles in a cell (or sector) use the same PN code to send their ARMs on the ARC; this avoids the need to have a separate receiver for each mobile, even in the off mode. If the number of sources is large, then more than one ARC may be used.
A MAC protocol is required on the ARC for the mobiles to access the base station with individual ARMs. One possible approach is to allow the mobile units to send ARMs in an asynchronous fashionxe2x80x94ADTX-MAC protocol. Another is a synchronous approachxe2x80x94SDTX-MAC protocol, in which a slotted frame structure is used for the access control of ARMs from all users.
Since the user sending a transmission request has already been registered and has acquired synchronization before, the timing ambiguity is mainly caused by the propagation delay uncertainty due to the movement of the mobile in a cell during the silent period. Hence, it is relatively easier to synchronize again than to acquire initial synchronization during the registration phase involving the access channel. On the other hand, the synchronization needs to be regained very quickly so that the arriving data burst can be transmitted without undue delay. Due to these reasons, the specific structure of the IS-95 access channel [3] which is used by the mobile station to initiate communication with the base station and to respond to paging channel messages, is no longer suitable, since its access probe occupies several 20 ms frames in time. Instead, much shorter access request messages are used within the access reservation channel structure significantly different from the IS-95 access channel. Such an approach dramatically reduces access delay and increases throughput.
SDTX-MAC Protocol
In the SDTX-MAC system, a time-slotted frame structure is used to accommodate access requests from different users on the access reservation channel (ARC). Specific time slots in the frame equal in length to the duration of the access request message (if necessary, a small guard time may be added) are assigned by the base station to mobile users after registration (one slot per user). Collision is thus avoided and there is no need of inserting an identifier appendix after the synchronizing part of the ARM. A method of step-increase of power is used for ARMs. After each ARM, the mobile monitors the paging channel for an acknowledgment (ACK) from the base station. If the elapsed time before the ACK is received is longer than the prescribed maximum, the corresponding ARM is regarded as a failure, and next one is sent at a power level increased by a fixed step. For each user, a fixed number of ARMs of increasing powers form an ARM sequence. If the synchronization is still not acquired after the sequence of ARMs is sent, a new sequence is started, with the transmitting power starting from the lowest level. Identical ARM sequences are repeated up to a maximum allowed number of repetitions, which is assumed large enough to ensure acquisition. The synchronism acquired through the ARC may be coarse, but it is sufficiently accurate to receive data packets from the user in question on a dedicated data channel. Each data packet sent on that channel is preceded by a short synchronizing preamble to refine synchronism.
The number of slots in one slotted frame of the access reservation channel (ARC) is designed to accommodate the expected number of registered users in a cell or sector. Once a user is registered, a slot is assigned to him on the ARC, and the base station subsequently uses that assignment to identify a user sending an access request. An example is shown in FIG. 2 wherein there are four slots within one frame, Tp, TF are the slot and frame lengths, respectively, and there are three ARMs within one access message sequence.
ADTX-MAC Protocol
The asynchronous discontinuous transmission medium access control (ADTX-MAC) protocol is in general terms similar to that used in the IS-95 access channel. It is a spread slotted ALOHA [4]-[6] with p-persistence [7] (plus sequence back-off) between ARM sequences. As shown in FIG. 3 a fixed number of ARMs forms an ARM sequence (three ARMs within an ARM sequence in this figure), with the transmission power increasing consecutively by a fixed increment. There is a random back-off TR between ARMs in the sequence, if the ACK is not received before time-out, TA. If the second ARM sequence is required, there is a random back-off TS before a p-persistence test, for the next ARM sequence to start. To reduce the probability of collision, the exact transmission time of each user is pseudo-randomly delayed from the slot start time, the delay being known to the base station.
Since all the users use the same PN code to spread their ARMs, each ARM consists of one synchronization preamble and an appendix for user identification. This appendix is designed to have the same length as the preamble, and is block-coded to provide the necessary error protection. The ARM for ADTX-MAC is of twice the length of an ARM in SDTX-MAC protocol.
SDTX-MAC can provide delay characteristics superior to those of the ADTX-MAC, but ADTX-MAC""s throughput may be larger or smaller than that of the SDTX-MAC depending on the offered traffic and the selected maximum value of the randomization delay. This is also intuitive, since ADTX-MAC""s access request message (ARM) must include an appendix, which increases the access delay. On the other hand, due to PN spreading and randomization procedure, more than one ADTX-MAC""s ARM within one time slot can be received successfully without collision, and clearly only one ARM can be transmitted per slot in SDTX-MAC. Even if the time slot is normalized to enable fair comparison, ADTX-MAC may still provide better throughout characteristics. The reason is that, although SDTX-MAC does solve the collision problem, and takes advantage of TDMA structure, it does not take advantage of the interference suppression capabilities of spread spectrum, and thus its performance is not optimal. On the other hand, ADTX-MAC does take advantage of spread spectrum, but it does not solve the potential collision problem.
When the transmitted signal propagates through a multipath fading channel, its replicas will arrive at the receiving end at different times spread over the maximum excess delay interval. If we denote the maximum excess delay expressed in chip intervals by xcfx84M, it is reasonable to assume that when the temporal separation of signals arriving from different users is larger than (xcfx84M+1) chip intervals, collisions will not occur. If we assume that the start times of transmitted packets form a Poisson point process with the arrival rate xcex packets/s, and denote the duration of a packet in seconds as Tp, the offered channel traffic G (in packets) will be:
G=xcexTp
The present invention provides for an improved multiple access protocol that improves upon the ADTX-MAC protocol and the SDTX-MAC protocol.
The limitations in the SDTX-MAC and ADTX-MAC discussed above are addressed by the following invention, which has been called minislotted SDTX-MAC, or M-SDTX-MAC.
Accordingly, there is provided a method of transmitting packets in a telecommunications system. Packets are transmitted from multiple terminals, in which the packets are spread with an identical spreading sequence for each terminal. The packets are transmitted in frames. An aspect of the invention includes allocating a respective mini-slot in each frame to a particular terminal as an identification reference for a packet transmitted from the particular terminal in the respective time slot. Further, at each terminal, packets are transmitted from the terminal beginning at a time within the mini-slot allocated to that terminal, with the packet being longer than the mini-slot.
In one aspect of the invention, the method is used to gain access to packet data transmission channels in a cellular radio CDMA system. The packets may thus be access request messages (ARMs). The packets may also be data packets.
In a further aspect of the invention, there is provided a method of transmitting ARMs to gain access to a packet data telecommunications channel, comprising the steps of:
transmitting ARMs from multiple terminals as overlapping packets, where each identical packet contains several repetitions of an identical spreading sequence for each terminal; the ARMs corresponding to different terminals being arranged into frames;
allocating a respective mini-slot in each frame to a particular terminal as an initial synchronization and identification reference for an ARM transmitted from the particular terminal; each ARM being longer than its associated mini-slot, but the ARM beginning inside the mini-slot; and
at each terminal, beginning to transmit data from the terminal after a base station allocates to it a packet data transmission channel upon successful receipt of an ARM.
Each mini-slot should be sufficiently long to avoid a collision between ARMs sent from different terminals.
In a further aspect of the invention, the data packet, or ARM, is transmitted within a cell over a radio channel, the channel has a cell-size dependent propagation delay and a maximum excess delay, and each mini-slot has a length at least equal to the maximum excess delay plus twice the maximum expected propagation delay plus guard time.
The mini-slot may be allocated to a terminal upon registration of the terminal in a telecommunications system.
These and other aspects of the invention, including apparatus for implementing the invention, are described in the detailed description of the invention and claimed in the claims that follow. | {
"pile_set_name": "USPTO Backgrounds"
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Autosomal dominant polycystic kidney disease (ADPKD) is an exceptionally common hereditary nephropathology with an incidence of about 1 in 800 live births. The disease is progressive, phenotypically characterized by bilaterally enlarged polycystic kidneys, and typically resulting in end-stage renal disease (ESRD) by the age of 65 years. The more common complications include hypertension, macrohaematuria, urinary-tract infection, cardiac-valve abnormalities, and hernia of the anterior abdominal wall. Cyst formation is also commonly observed in the liver, although the occurrence is not associated with functional impairment of the organ. Although not as frequently reported, additional extrarenal manifestations include pancreatic cysts, connective tissue abnormalities, and cerebral-artery aneurysms.
The typical age of onset is in middle life, but the range is from infancy to 80 years. The clinical presentation of ADPKD differs between and within families as partly explained by the genetically heterogeneous nature of the disorder. Mutations in two genes, PKD-1 and PKD-2, account for nearly all cases of ADPKD (e.g., for reviews, see Arnaout, 2001, Annu Rev. Med. 52:93-123; Koptides and Deltas, 2000, Hum. Genet. 107:115-126). PKD-1 and PKD-2 encode integral membrane proteins whose functions have not been fully elucidated. The major gene responsible for ADPKD, PKD-1, has been fully characterized and shown to encode an integral membrane protein, polycystin 1, which is thought to be involved in cell-cell and cell-matrix interaction. PKD-2 gene encodes polycystin-2 which is a predicted integral membrane protein with non-selective cation channel activity. Based on sequence homology with the alpha 1 subunit component of voltage-activated calcium channels, it has been postulated that polycystin-2 may play a role in ion channeling. The C-terminal cytoplasmic tails of polycystin-1 and polycystin-2 have been shown to interact using in vitro binding assays and in a directed two-hybrid interaction. The interaction occurs via a coiled-coil domain in PKD-1 and a region near R872 in PKD-2. Although the biological relevance of the interaction between the polycystins is not yet understood, it does suggest that PKD-1 and PKD-2 are likely to function along a common pathway.
Both ADPKD type 1 and type 2 share the entire range of renal and extrarenal manifestations, but type 2 appears to have a delayed onset relative to type 1. The common phenotypic complications observed for ADPKD including hypertension, hematuria, and urinary tract infection seem to be clinically milder in type 2 patients. The median age at death or onset of ESRD has been reported as 53 years in individuals with PKD-1 and 69 years in those with PKD-2. Women have been reported to have a significantly longer median survival of 71 years than men (67 years). No sex influence is apparent in PKD-1. Mutations in the PKD-1 gene are the cause of ADPKD in approximately 85% of the cases tested, while those in PKD-2 account for 15%. Although a small subset of families with ADPKD fail to demonstrate genetic linkage to either PKD-1 or PKD-2, raising the possibility of a third gene for ADPKD, the existence of a third disease-associated locus has been strongly challenged.
Despite the discovery of strong links between genetic alterations in PKD genes and the onset of ADPKD, the development of a genetic testing method for ADPKD predisposition for routine clinical use has been hindered by several technical obstacles.
One serious obstacle for developing a DNA-based testing method for ADPKD is that sequences related to the PKD transcript, for example, PKD-1, are duplicated at least three times on chromosome 16 proximal to the PKD-1 locus, forming PKD-1 homologues. Another obstacle is that the PKD-1 genomic interval also contains repeat elements that are present in other genomic regions. In addition, the sequences of PKD genes are extremely GC rich and a large number (15,816 bp) of nucleotides need to be analyzed for a thorough evaluation.
There is a need for the identification of segments of these sequences that are unique to the expressed PKD genes and not are present in the duplicated homologous sequences. There is also a need for developing a sensitive and specific genetic testing method for mutational analysis of PKD genes. The development of such genetic testing method would facilitate the diagnosis and management of ADPKD. | {
"pile_set_name": "USPTO Backgrounds"
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Conventional microwave ovens, though possessing many advantages, suffer from an inability to heat items placed within them evenly at all points on their surface. The unevenness of the microwave oven prepared comestible is in part the result of the unevenness of the incident microwave energy. This problem can be circumvented by varying the cooking process or by incorporating an energy moderator. By varying the cooking process to periodically reposition the article being cooked, cooking evenness can be improved. However, varying the process inevitably means that greater attention is required. Thus a variety of moderators have been proposed to avoid the requirement of attention to the cooking comestible.
One approach has been to provide a mechanism which automatically repositions the food item within the microwave energy field. Rotating shelves, for example, that described in U.S. Pat. No. 3,428,773 issued Feb. 18, 1969 to Waldenfels, have been introduced to lessen the effects of nonuniform fields of microwave energy in microwave ovens. In a converse approach, the food is kept stationary and the field is "moved" or "stirred". Rotating mode stirrers, such as that disclosed in U.S. Pat. No. 3,819,900 issued June 15, 1974 to Ironfield, have been provided to lessen the non-uniformity of the field of microwave energy in microwave ovens.
Another approach has been to partially or selectively shield the item being cooked with a specially designed food container. For example, U.S. Pat. No. 3,547,661 which issued Dec. 15, 1970 to P. N. Stevenson discloses a container and food heating method where apertures of various sizes are provided on the top and bottom in registered relation. Such apertures may also be partially masked by microwave reflective material as indicated in FIGS. 1 and 3, areas 25-28. Various sizes of apertures or of partial masking ostensibly provide means for selectively heating different items at different temperatures simultaneously. U.S. Pat. No. 4,013,798 which issued Mar. 22, 1977 to Costase also discloses a selectively shielded microwave cooking structure comprising registered openings of various sizes. The use of apertures of various sizes and shapes in the top of a microwave cooking food tray which is otherwise microwave reflective is disclosed in U.S. Pat. No. 3,672,916 which issued June 27, 1972 to H. J. Vernig and U.S. Pat. No. 3,219,460 which issued Nov. 23, 1965 to E. Brown.
The prior art also includes means in the form of a cooking container for moderating the incoming microwave energy. For example, U.S. Pat. No. 4,144,438 issued on Mar. 13, 1979 to Gelman describes a microwave energy moderating bag with a foil lamina 23 perforated by an array of apertures 30 which are sufficiently large and numerous to render the bag 20 substantially transparent to microwave energy of a predetermined frequency. However, the apertures are sufficiently small that such microwave energy which passes into the bag in a microwave oven will be sufficiently moderated to precipitate uniform cooking of a foodstuff disposed therein.
Water has been used in the past to improve the evenness of the cooked foodstuff. For example, Soviet Pat. No. 501,748 issued Feb. 5, 1976 discloses a cooking bag for meat or fish which involves surrounding the food with two closed, unvented cellophane bags having water between the two bags in an amount up to 15% of the weight of the food. The food is cooked by a series of 2 to 3 minute heating cycles separated by 2 to 3 minute cooling cycles. A similar approach is to convey the food item through a water bath where it is exposed to microwave energy. Examples of such devices are disclosed in German Offenlegungsschrift Pat. No. 2,704,563 issued Aug. 25, 1977 and U.S. Pat. No. 3,809,845 issued May 7, 1974 to Stenstrom. Stenstrom discloses a thick water layer (2.5 mm.) above and below the food portion. In addition, it is known that the Litton Company of Minneapolis, Minn. is currently marketing a device known as a "Simmer Pot" which is a porous clay pot with a water absorbent clay lid which is soaked in water for 30 minutes to overnight. After soaking the lid, the food item is placed within the closed clay pot and cooked. A similar device is marketed by El Camino Products, Inc. of Penoga Park, California under the brandname Olde World Roaster.
The prior efforts to make the cooking of food items within a microwave oven more uniform are subject to a variety of shortcomings. Devices which require oven redesign are of little use to current oven owners. Devices using metallic elements are prone to arcing problems which must be avoided with concommitant increase in the cost of the product. Devices using water baths are not suitable for use in the home, and bags with water requiring short cooking cycles or long soaking cycles are inconvenient. Most importantly the prior practice in this field is subject to improvement in terms of the extent of evenness of the cooked comestible which is accomplished. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to pipe laying apparatus, and more particularly it is concerned with a pipe laying apparatus suitable for laying pipes of relatively small diameter.
Nowadays, a propulsion process is becoming more popular as a process for laying pipes of relatively small diameter or a diameter of less than 1000 mm than an opencut process that has hitherto been adopted. In the propulsion process, propulsion means, such as hydraulic cylinders, are installed in a starting pit for pressing pipes to be laid at a rear end thereof to propel same while forcing the earth ahead of the pipes to be compacted, to thereby lay the pipes underground. This propulsion process is specifically referred to as a compaction type system. Some disadvantages are associated with the compaction type system. That is, the pipes to be laid under ground are merely pressed at the rear thereof by the hydraulic cylinders, so that a resistance of high magnitude is offered to the movement of the pipes by a force of friction acting between the pipes and the earth through which they are propelled. This makes it necessary to use hydraulic cylinders capable of producing a pressing force of high magnitude. Also, the pipes tend to be damaged because of a force of high magnitude exerted thereon, and the pipes propelled tend to be deflected from the designed path of movement with a low degree of directional precision.
Proposals have been made to develop improved pipe laying apparatus by obviating the aforesaid disadvantages of the prior art. They include a pipe laying apparatus of a rotation excavation type as disclosed in Japanese Patent Application Laid-Open No. 29797/82, which includes an excavator equipped with a rotary excavating tool and excavates the earth by the excavator while propelling pipes to be laid by hydraulic cylinders to thereby lay the pipes underground and a pipe laying apparatus of a lateral vibration excavation type as disclosed in Japanese Patent Application Laid-Open No. 123393/82 and No. 135299/83, which incudes a vibration excavator attached to a formed end of the leading pipe and excavates the earth by the vibration excavator while propelling pipes to be laid by hydraulic cylinders, the vibration excavator having a shaft mounting eccentric weights located at right angles relative to the center axes of the pipes to be laid to produce lateral vibration with rotation of the shaft.
In the pipe laying apparatus of the rotation excavation type the earth is excavated by rotating the rotary excavating tool while a viscosity imparting liquid is being injected into the earth in the vicinity of the surface at which excavation is carried out, and at the same time the soil as excavated is mixed with the viscosity imparting liquid and agitated to produce a viscosity imparting liquid containing soil which is conveyed under pressure toward the starting pit through an annular passage defined between a hole formed by excavation and the pipes to be laid. In the pipe laying apparatus of the vibration excavation type, a forward end portion of the excavator is caused to vibrate to crush the earth into minuscule particles while a viscosity imparting liquid is being injected into the earth in the vicinity of the surface at which excavation is carried out, and at the same time the soil as excavated is mixed with the viscosity imparting liquid and agitated by the vibration of the excavator to produce a viscosity imparting liquid containing soil which is conveyed under pressure toward the starting pit through an annular passage defined between the hole formed by excavation and the pipes to be laid.
The pipe laying apparatus of the rotation excavation type can have application in the earth layers such as sand, clay, etc., but when it is a gravel layer including solid particles such gravels, the problem arises that it is difficult to convey the excavated soil toward the starting pit for discharging thereof. Meanwhile, the pipe laying apparatus of the vibration excavation type offers the advantage that even if the earth contains solid materials such as gravel, they can be embedded in the earth by the vibration while allowing only the viscosity imparting liquid containing soil of high viscosity to be discharged to the starting pit. However, this type encounters the problem that when the earth layer is clay, it is difficult to improve operation efficiency and achieve a high excavation speed unless the amplitude of vibration of the excavator is increased, while if the amplitude is increased, the vibration of the ground surface increases in magnitude.
Proposals have been made, as described in Japanese Patent Application Laid-Open No. 44194/83, for example, to use a pipe laying apparatus which possesses the merits of both the rotation excavation type and the vibration excavation type by mounting a vibrator in the excavator body having a rotary excavating tool for allowing rotation and vibration excavations to be effected, so that the apparatus can cope with a wide range of earth layers including sand, clay, gravel, etc.
Meanwhile, the pipe laying apparatus of the above-mentioned vibration excavation type also suffers the disadvantage that since the excavator body vibrates as a whole, the vibration of the excavator is transmitted to the pipes to be laid which are rigidly connected to the excavator body. Thus, the pipes to be laid are caused to vibrate simultaneously as the excavator body vibrates, and therefore it becomes necessary to increase the size of the excavator to increase the magnitude of the vibration produced.
The pipe laying apparatus of the combined rotation and vibration excavation type as disclosed in Japanese Patent Application Laid-Open No. 44194/83, noted hereinabove, has the same disadvantage as the pipe laying apparatus of the vibration excavation type since the vibrator mounted inside the excavator body causes the excavator body to vibrate as a whole.
On the other hand, vibratory excavators have been developed which are provided with means for avoiding transmission of vibration to pipes to be laid. This type of excavator is disclosed in Japanese Patent Application Laid-Open No. 146896/82, for example, which comprises a cylindrical support, a vibrator generally of a cylindrical shape and having a conical forward end portion, the cylindrical portion being coaxially inserted in the cylindrical support, a plurality of shock absorbing small-diameter rods mounted between a rearward end of the vibrator and a forward end of the support to connect them together in such a manner that the small-diameter rods are arranged in a circle concentric with the support and the cylindrical portion of the vibrator, and a bellows of resilient material mounted between the forward end of the support and a back surface of the conical forward end portion of the vibrator. The vibrator has a rotary shaft journalled in the cylindrical portion thereof coaxially therewith, and an eccentric weight is mounted on the rotary shaft which is connected to a drive motor. A pipe laying apparatus equipped with this type of vibratory excavator offers the same advantages as the first-mentioned pipe laying apparatus of the vibration excavation type of the prior art.
Moreover, the vibrator excavator noted hereinabove is equipped with shock absorbing small-diameter rods interposed between the support and vibrator. This causes a thrust applied to the pipes to be laid by hydraulic cylinders to be transmitted to the vibrator, while, the vibration of the vibrator (vibration which is at right angles to the axes of the support and the cylindrical portion of the vibrator) is absorbed by the small-diameter rods which are flexed at right angles to the axes of the support and the cylindrical portion of the vibrator, so that the vibration of the vibrator is prevented from being transmitted to the pipes to be laid through the support. Stated differently, the vibrator and the pipes to be laid are connected together in flexible coupling through the small-diameter rods and support. This makes it possible to provide improvements in the first-mentioned vibratory excavator of the prior art which suffers the disadvantage that the excavator should be large in size to develop a vibration of high magnitude due to the vibration to be transmitted to the pipes to be laid.
The problem raised with regard to this type of vibratory excavator is that the arrangement whereby a plurality of small-diameter rods are mounted between the support and vibrator to bear the thrust applied by the hydraulic cylinders has the risk that the small-diameter rods might be ruptured when the thrust applied thereto is high in magnitude. | {
"pile_set_name": "USPTO Backgrounds"
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As disclosed in Patent Document 1, an image forming apparatus, such as a laser printer, includes a toner container as a toner case to be attached to an apparatus main body. The apparatus main body is provided with an image forming portion including a developing portion.
The toner container includes a case body in which a toner as a developer is contained. The case body is provided with a toner supplying portion which supplies a toner to the developing portion of the apparatus main body. Further, at an inside of the case body, a screw portion which conveys the toner to the toner supplying portion and a stirring mechanism which stirs the toner are provided.
The stirring mechanism includes a shaft driven to rotate at the inside of the case body, and a stirring sheet attached to the shaft. The screw portion includes a screw shaft driven to rotate at the inside of the case body, and a spiral conveying blade formed on an outer face of the screw shaft and elongated along an axial direction of the screw shaft. One end of the screw shaft is rotatably supported by a bearing formed at the inside of the case body. Meanwhile, another end of the screw shaft is supported by a driving member, which transmits a driving force of a motor, at the inside of the case body.
Further, the toner contained at the inside of the case body is stirred by the stirring mechanism and is conveyed to the screw portion. The toner having been conveyed to the screw portion is conveyed to the toner supplying portion by the screw portion. Thus, the toner is supplied from the toner supplying portion to the developing portion outside the case body.
[Patent Document 1] Japanese Unexamined Patent Application, Publication No. 2010-176033 | {
"pile_set_name": "USPTO Backgrounds"
} |
The use of intra-aortic balloon assemblies for assisting the pumping action of the heart are well-known. Recently, research efforts have placed emphasis upon facilitating the insertion and placement of such balloon assemblies. One of the major objectives is to obtain reductions in balloon profile, i.e. outer diameter, in order to achieve the aforementioned results. Early efforts to achieve such results led to the technique of evacuating the balloon and wrapping the evacuated balloon about an elongated member substantially coaxial with the longitudinal axis of the balloon. This technique is disclosed in U.S. Pat. No. 3,939,820 issued on Feb. 24, 1976 to Grayzel et al. Another technique adopted to achieve substantially similar results utilizes a twistable, elongated stylet coaxial with the longitudinal axis of the balloon, one end of the balloon being rotatable relative to the opposing end, and being twisted about the stylus in order to reduce the balloon profile. This technique is disclosed in U.S. Pat. No. 4,261,339 issued Apr. 14, 1981 in the name of Hanson et al. A novel improvement on this technique is disclosed in application Ser. No. 253,680, filed Apr. 13, 1981 now U.S. Pat. No. 4,422,447 issued Dec. 27, 1983 in the name of the inventor of the present invention, and disclosing an intra-aortic balloon assembly having a stylet rotatable through a manually operable control knob arranged remote from the balloon, for wrapping the balloon.
The balloons of the above techniques which employ a flexible stylet may be introduced into the body through a percutaneous technique such as, for example, the Seldinger technique, wherein an introducer sheath is initially introduced into the body and the balloon is thereafter introduced into the body by insertion into and through said introducer sheath, which may then be either partially or totally removed after the balloon has been properly placed.
Still another technique for reducing the profile of the balloon but without either wrapping or twisting, is disclosed in U.S. Pat. No. 4,327,709 issued on May 4, 1982, to Hanson et al, and describing a technique in which the balloon is evacuated to form a flat tape-like cross-section with the stylet lying along the central axis thereof. The two halves of the balloon lying on either side of the stylus are folded over to form first and second longitudinal folds. The balloon is thereafter inserted into one end of an insertion sheath used in the performance of the Seldinger technique. This technique assumes that the balloon will form a sufficient number of additional longitudinal folds to enable its insertion into the insertion sheath.
Although all of the above-mentioned techniques tend to reduce the profile of the balloon, they nevertheless exhibit certain disadvantages. For example, the balloon assemblies which rely upon twisting techniques create a large number of folds to generate a non-uniform helical pattern which may damage the introducer sheath and/or the patient or the balloon itself, which is greatly stressed by such wrapping. The balloon assemblies adapted for folding and/or wrapping techniques also create a large number of folds, due to their geometry and thus all of the above techniques fall short of reaching a minimal outer profile and without introducing additional disadvantages. In addition thereto, none of the above techniques teach a pre-wrapped balloon, or a method or means for maintaining a pre-wrapped balloon in the fully and tightly wrapped state, until it is ready for insertion. | {
"pile_set_name": "USPTO Backgrounds"
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In recent years a number of industries have adopted the FIBC or bag-in-box concept for storing and transporting liquid and particulate commodities in relatively large quantities. For example, the FIBC or bag-in-box concept has been employed for transporting in bulk such diverse products as vegetable oils, salad dressings, syrups, soy sauce, peanut butter, pharmaceuticals, talc, motor oil, industrial chemicals, detergents in liquid or powder form, and toiletry products or ingredients.
The FIBC concept is a bulk container system comprising a flexible liner in a flexible or semi-flexible bag. In one embodiment, a FIBC bag is made of a woven material (e.g., woven polymer, TYVEX®, canvas, wire mesh or net). The flexible liner is typically chemically resistant and impermeable to water and air and serves as the container for a selected commodity. The FIBC bag serves as a protective container for the liner and its contents. A FIBC bag is described in U.S. Pat. No. 4,596,040 to LaFleur et al., which issued Jun. 17, 1986, and is hereby incorporated by reference in its entirety.
The bag-in-box concept comprises a flexible liner and a rigid or semi-rigid box. The flexible liner is typically chemically resistant and impermeable to water and air and serves as the container for a selected commodity. The box may be made of plywood or other wood materials, cardboard, fiberboard, metal or plastic. The box serves as a protective container for the liner and its contents. A box for a bag-in-box system is disclosed in U.S. Pat. No. 6,533,122 to Plunkett, which issued Mar. 18, 2003, and is hereby incorporated by reference in its entirety. A bag for use in a bag-in-box system is described in U.S. patent application Ser, No. 10/818,882, which was filed Apr. 6, 2004, is entitled “Bag With Flap For Bag-In-Box Container System” and is hereby incorporated by reference in its entirety.
By way of example, a liner used for shipping commodities in bulk, via a FIBC or bag-in-box system, typically may have a volume in the order of 60 cubic feet. In one embodiment, the liner will include at least a drain fitting near the bottom of the liner whereby the liner's contents may be removed. In other embodiments, the liner will include at least a filler fitting near the top of the liner whereby the liner may be filled with its contents. In other embodiments, the liner will include both a filler fitting near the top of the liner and a drain fitting near the bottom of the liner. In one embodiment, the drain fitting is on the gusseted side as described in U.S. Patent Application Ser. No. 60/720,855, which was filed Sep. 26, 2005, entitled “Flexible Liner With Fitting On Gusseted Side” and which is hereby incorporated by reference in its entirety.
The liner may be of any suitable configuration. For example, the liner may be generally shaped like a cube. It also can be configured so that a cross-section that is generally parallel to the top and bottom of the liner is square, rectangular, circular, or any other suitable geometry.
In embodiments of the liner with at least a drain fitting, the outer container (i.e., the bag of a FIBC system or the box of a bag-in-box system) is provided with a discharge opening near or at the bottom end of the outer container through which the liquid or particulate contents can be discharged from the liner via its drain fitting. The discharge opening of the outer container may be fitted with a drain fitting that mates with or accommodates the drain fitting of the liner. This mating arrangement between drain fittings of the liner and outer container ensures that material discharged from the liner will be directed to the intended receiving facility and prevents the material from accumulating in the bottom of the outer container.
In embodiments of the liner with at least a filler fitting, the outer container usually comprises a cover or top panel that is removable to permit access to the liner and the filler fitting.
One consideration of the FIBC or bag-in-box mode of shipment of materials in bulk is that the outer container can be a non-returnable or one-way container. For example, where the outer container is a box for a bag-in-box system and is generally made of a corrugated fiberboard or the like, the box can be discarded after use. Alternatively, the box may consist of interlocking panels of metal, wood, or a stiff or rigid plastic material, in which case the box may be disassembled and returned to the shipper after the associated liner has been emptied of its contents.
Where the outer container is a bag for a FIBC system and is made of a low cost woven material, the bag can be discarded after use. Alternatively, where the material of the bag is more expensive, the bag may be collapsed and returned to the shipper after the associated liner has been emptied of its contents.
With respect to the FIBC and bag-in-box concepts as applied to bulk shipment of commodities, the plastic flexible liners have taken various forms. One common form is the so-called “pillow” type, which consists of at least two sheets of film sealed together at their edges. An example of this is described with respect to U.S. patent application Ser. No. 11/361,691, which was filed Feb. 24, 2006, entitled “Flexible Liner For FIBC Or Bag-In-Box Container Systems With Improved Flex Crack Resistance” and is hereby incorporated by reference in its entirety. Another common form is the six-sided flexible liners (e.g., liners that take the shape of a cube or rectangular parallelepiped when filled) made from a plurality of sheets of film.
Regardless of the form the liner takes, the liner can be formed via a registration and tracking process. The registration and tracking can be performed using an optical scanner or any type of device that is capable of reading or detecting a marking placed on an item (or a section of an item), or of noticing differences in shape, size, texture, height or other physical variation in an item (or the absence of an item). The device uses the information obtained from the item to determine the position of the item. When multiple sections of an item are being combined from multiple locations, the information obtained by the device may be used to aid in combining the sections at the correct places.
The items are transported on transportation devices/conveyors to a desired location to be combined. The registration and tracking system uses the position information of the sections of the item and accordingly increases, decreases, or maintains the speed of the transportation devices so that when the multiple sections of an item are combined they are combined at the correct place.
Another method of forming the liner is through the use of a nip drive. The nip drive rotates a desired amount of revolutions in order to produce a desired amount of material to be processed. The nip drive eliminates the need for optics and can be useful if the item does not contain a registration mark. Furthermore, liners can be formed by hand without the use of large or complex machinery.
Traditionally, all the sections of a flexible liner are composed of polyethylene layers. Polyethylene tends to stretch and is limited in the amount of heat that can be applied to it. When sections of polyethylene stretch, the registration and tracking process, or nip drive operator, may not detect the stretching, causing misalignment of the item when the sections are combined. Also, when the sections are sealed together, the polyethylene is weakened by the heat used to form the seal and is susceptible to tearing. When multiple plies or layers of polyethylene are used to form the sections, the heat needed to seal the sections together is generally higher than the heat needed to seal sections comprised of a single ply or layer of polyethylene. As the heat used to seal the polyethylene layers together increases, the susceptibility of the polyethylene layers to tearing also increases. Therefore, polyethylene layers are generally weakened more in multiple layer applications than single layer applications. This is particularly the case where there are multiple layers joined together, such as at the apex of the liner. All of these difficulties increase the cycle time of the manufacturing process and decrease the quality of the liner. Some flexible liners use high heat threshold materials, e.g., nylon, on all sides of the liner. The nylon is used to strengthen the seals of the liner and prevent tearing and stretching of the liner. Nylon, however, is expensive.
There is a need in the art for a system and method of reducing the cycle times and costs, and improving quality, of manufacturing liners in a FIBC or bag-in-box container system. | {
"pile_set_name": "USPTO Backgrounds"
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A fiducial marker is an object placed in the field of view of an imaging system which appears in the image produced, for use as a point of reference or a measure. It may be either something placed into or on the imaging subject, or a mark or set of marks in the reticle of an optical instrument.
Several exemplary fiducial markers are illustrated in FIGS. 1A, 1B and 1C. In particular, FIG. 1A illustrates a binary ID marker, which usually provides a small range of data. For example, ArUco (a BSD licensed open source software library) provides 1024 different patterns, each associated with an ID between 0 and 1023, and each pattern can be used to represent different information. FIG. 1B illustrates two circular markers, which also usually provide a small range of data. FIG. 1C illustrates binary data markers (for example, QRCode, DataMatrix, PDF417), which can store more information, for example, QR code can provide a data storage up to 2936 bytes.
In general, the more data is to be embedded into a marker, the more detailed the marker will be, and thus the detection of the marker from a distance becomes more difficult. | {
"pile_set_name": "USPTO Backgrounds"
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In both commercial and industrial facilities, particularly those that process food, the interior surfaces, such as the walls, are subject to frequent cleaning. The surfaces are cleaned with hot water, typically at least 140° F. and often as much as 160° F. Detergents, often containing chlorine, are used in the hot water to emulsify grease and kill bacteria. Over time, the combination of chemicals and hot water deteriorate the finishes on these interior surfaces. For example, a paint finish begins to crack, peel and chip or may be marred. The walls, often constructed of insulated metal panels in those facilities that process foods at colder temperatures, may have begun to rust and corrode. There may also be holes or dents in the walls or seams between various construction materials that trap water and bacteria, and are difficult to clean.
The facility owner may then decide, perhaps urged by health inspectors, to recondition the facility. Often reconditioning is limited to simple and traditional painting because a prolonged shutdown of production operations for more extensive reconditioning efforts is prohibitive. Eventually, the facility may become so deteriorated that complete reconditioning is required, assuming that the facility can be reconditioned at all.
There is thus a need for a way to recondition such facilities that is more durable than traditional and simple painting but which can be completed without loss of production time so as not to impede facility operations. | {
"pile_set_name": "USPTO Backgrounds"
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Traditional methods for treating certain injuries to a body (e.g., humans, animals) involve setting and immobilize the injured member to allow natural healing of the injury. Often, it is desirable that natural healing will restore damaged structures to their original uninjured condition without significant inconvenience to a patient. Traditional problems in injury treatments have been associated with the inability of the patient's body to heal correctly or rapidly and the inability of the healed part to regain fall strength and freedom of movement. These problems are especially acute in patients with suboptimal health and reduced healing capacity such as elderly, bedridden or patients with multiple disorders.
Attempts to address these problems and to promote more rapid healing have led to the use of pulsed electromagnetic fields. It is generally known that electromagnetic fields applied to a body can produce favorable biological effects. For example, FDA approved pulsed electromagnetic field (PEMF) apparatuses are available for use in bone healing. These apparatuses are used to augment and accelerate the natural healing process. PEMF is also effective in the treatment of severe injuries and fractures which are not otherwise treatable using conventional techniques.
Known methods and apparatuses which have been used to treat injuries using PEMF include the use of Helmholtz and toroidal coils to deliver PEMF. These methods and apparatuses have suffered from various deficiencies. For example, Helmholtz coils suffer from field inhomogeneity and field dropouts (e.g., the field drops to zero near the center of the coil). Toroidal coils are inefficient and have a relatively weak field strength. Further, known methods of PEMF treatment have problems associated with system complexity, large size and weight, long treatment times, weak PEMF strength and low efficiencies in promoting healing. Current devices and methods of PEMF treatment further fail to provide adequate mobility during treatment. Other drawbacks also exist. | {
"pile_set_name": "USPTO Backgrounds"
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In applications where high voltage semiconductor devices operating in high voltage conditions are controlled, high breakdown voltage transistors are typically used in corresponding control circuits. For example, in traditional gallium nitride (GaN) power management applications, transistors such as laterally diffused metal oxide semiconductor (LDMOS), bipolar or high voltage metal-oxide-semiconductor field-effect transistors (MOSFETs) can be utilized to control the GaN devices operating in high voltage conditions. Since these control transistors typically have poor figure of merit (FOM), compared to the FOM of the GaN devices, which can thereby, for example, limit the operating frequencies of the GaN devices, the overall circuit (e.g. power management) can be limited in performance by the large, high voltage control transistors which can be difficult to charge and discharge quickly (e.g. their FOM is too high) and therefore the benefit of using the GaN devices can be substantially reduced.
Alternatively, low breakdown voltage transistors may be used to control the high voltage semiconductor devices. The low break down voltage transistors may operate in circuits having different voltage (i.e. supply) domains, such as a first low voltage circuit operating with respect to a fixed reference voltage (e.g. 0 volts) and a second low voltage circuit operating with respect to a flying (i.e., switching) reference voltage, where the reference voltage can switch from a low reference voltage (e.g. 0 volts) to a high reference voltage (e.g. 12-100 volts and higher). One such implementation is described, for example, in the above referenced U.S. Pat. No. 9,484,897, the disclosure of which is incorporated herein by reference.
Prior art implementations using low breakdown voltage transistors use non-galvanic coupling (e.g. capacitive, magnetic, optical) between the first and second low voltage circuits to transmit timing control information from one voltage domain to the other. Due to the nature of the non-galvanic coupling, only an AC component of the timing control information may be transmitted through the coupling.
Accordingly, some prior art implementations with non-galvanic coupling regenerate the timing control signal in the second voltage domain based on a leading and a trailing edge of a pulse signal representing the timing control information in the first voltage domain. This means that the second circuit operating in the second voltage domain must be fast enough to operate on such edges and be immune to side effects of the flying reference voltage with respect to which it operates. If such side effects cause an edge of the pulse signal not being detected, then inefficient and potentially damaging control of the high voltage semiconductor devices may be obtained.
Other prior art implementations with non-galvanic coupling may first generate bursts of a high frequency signal by gating the high frequency signal (e.g. as derived by an oscillator circuit) with a pulse representing the timing control information and transmit the entire burst through the non-galvanic coupling. In turn, the second circuit operating in the second voltage domain can recover the timing information by detecting the envelope of the burst signal, as described, for example in the U.S. Patent Publication US 2009/0206817 A1. Added complexity related to the introduction and manipulation of the high frequency signal, as well as coupling effects of such high frequency signal may render such implementation undesirable in some applications.
Based on the above, it may be desirable to provide methods and devices to control the high voltage semiconductor devices with low break down voltage transistors without the above-mentioned shortcoming of the prior art. | {
"pile_set_name": "USPTO Backgrounds"
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In decentralized networks, for example peer to peer overlay networks based on a distributed hash table, resources are distributed to the individual network nodes in a decentralized manner. It is possible in this process for each individual network node to search for corresponding resources with the aid of keywords. Checking values are used for this purpose, with a unique checking value being generated from a keyword. The checking values are managed by the network nodes, with each network node being responsible for predetermined checking values. Each of the network nodes is allocated a unique identifier from a key space. This can be a binary key space for example with a width of n bits. The checking values, which are likewise formed for example from the key space with a width of n bits, are used by network nodes to direct search requests for example into the network. A network node can also send so-called publication requests for a specific checking value to the network node responsible for the specific checking value. The transmitting network node uses such publication requests to give notice that it wishes to publish, in other words make available to the other network nodes, resources, which are assigned to the specific checking value and as a result to the corresponding keyword, in the network.
The checking values are for example hash values, which are generated using a hash algorithm. The checking values are preferably stored in a table, with each table entry containing a corresponding checking value and data assigned to this checking value, for example a reference to the storage location of corresponding resources.
This data is associated here with the keyword, from which the checking value was generated. The table is preferably distributed in a decentralized manner in the data network, with each network node being responsible for a value range in the table.
The instance can now occur that specific resources, in other words specific checking values, are requested, in particular searched for and/or published, particularly often by means of corresponding requests in the network. This results in overloading of the network nodes responsible for the corresponding checking values. Such network nodes are also referred to as hot spots. When a hot spot is overloaded, it can cause blocking and failure of said network node. As a result the network traffic in the region of this hot spot increases, endangering the stability of the network as a whole. The network also loses capacity.
To resolve the hot spot problem, it is known from the prior art that particularly popular data can be replicated to one or more network nodes. For example the popular data, for which a corresponding network node is responsible, can be replicated directly to adjacent nodes. Replication to any other network nodes, for example those specified by algorithms, is also possible however. However data replication poses the problem that it must always be ensured in the network that the replicated copies are up to date. This requires further specific mechanisms.
It is also known that a further logical network can be provided for the data network, to organize the requests in the network. This has the disadvantage that so-called “keep alive” messages are required, with the result that a relatively extensive transmission capacity bandwidth is taken up by the further logical network alone. It is furthermore necessary to manage connections, using the existing table that is distributed in a decentralized manner in the data network. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to the purification and concentration of synthetically manufactured biological molecules. More particularly, it relates to the purification and concentration of synthetically manufactured biological molecules, such as oligonucleotides, synthetic DNA and synthetic RNA, by ultrafiltration.
Synthetic biological molecules, such as oligonucleotides, synthetic DNA and synthetic RNA are being investigated as therapeutic agents. These molecules would be used in lieu of natural or recombinant molecules. There are a number of reasons for doing so. Some molecules just don't exist in nature or for some reason can't be replicated yet using recombinant technologies. Synthetic synthesis can overcome this limitation. Often, there are variants of eth same molecule. Synthetics allow one to custom tailor the molecule to its desired form. Lastly, synthetics and their manufacture are often less expense to manufacture and often avoid the issues of handling biohazards.
These molecules are typically formed by synthetic chemical precursors and are assembled on various solid substrates within synthesizers.
After formation, they need to be purified and in many instances concentrated, either for further processing or formulation.
The molecules generally are cleared from their solid support and then subjected to a purification step such as ultrafiltration or chromatographic capture to remove impurities.
The desired molecules are relatively small, typically having a molecular weight from about 0.5 to about 5 Kilo Daltons (KD).
As such, they are difficult to purify and concentrate by ultrafiltration as they are often about the same size as the membrane pore used to retain them. This results in relatively low yields of product being obtained Additionally, the membranes, having such small pore sizes, suffer from low fluxes and processing times can be measured in hours. This drives up the cost of the process as well as placing an undue burden on the membranes and the system components.
Due to this limitation, ultrafiltration is not widely accepted for this application and one uses chromatography, precipitation or distillation techniques to purify and concentrate these molecules.
These processes have their own disadvantages. They are biotech-based and most times, especially process scale chromatography, are more expensive than ultrafiltration. The precipitation often introduces an additional chemical that needs to be removed. Distillation may adversely affect the molecules especially any that are heat sensitive.
The present invention provides the means for enabling ultrafiltration in this application. | {
"pile_set_name": "USPTO Backgrounds"
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To provide cellular wireless communication service, a wireless service provider or “wireless carrier” typically operates a radio access network (RAN) that defines one or more coverage areas in which WCDs can be served by the RAN and can thereby obtain connectivity to broader networks such as the public switched telephone network (PSTN) and the Internet. A typical RAN may include one or more base transceiver stations (BTSs) (e.g., macro network cell towers and/or femtocells), each of which may radiate to define a cell and cell sectors in which WCDs can operate. Further, the RAN may include one or more base station controllers (BSCs) (which may also be referred to as radio network controllers (RNCs)) or the like, which may be integrated with or otherwise in communication with the BTSs, and which may include or be in communication with a switch or gateway that provides connectivity with one or more transport networks. Conveniently with this arrangement, a cell phone, personal digital assistant, wirelessly equipped computer, or other wireless communication device (WCD) that is positioned within coverage of the RAN can then communicate with a BTS and in turn, via the BTS, with other served devices or with other entities on the transport network.
Wireless communications between a WCD and a serving BTS in a given coverage area will typically be carried out in accordance with one or more agreed air interface protocols that define a mechanism for wireless exchange of information between the WCD and BTS. Examples of such protocols include CDMA (e.g., EIA/TIA/IS-2000 Rel. 0, A (commonly referred to as “IS-2000” or “1×RTT”), EIA/TIA/IS-856 Rel. 0, A, or other version thereof (commonly referred to as “IS-856”, “1×EV-DO”, or “EVDO”)), iDEN, WiMAX (e.g., IEEE 802.16), LTE, TDMA, AMPS, GSM, GPRS, UMTS, or EDGE, and others now known or later developed.
The air interface protocol will generally define a “forward link” encompassing communications from the BTS to WCDs and a “reverse link” encompassing communications from WCDs to the BTS. Further, each of these links may be structured to define particular channels, through use of time division multiplexing, code division multiplexing (e.g., spread-spectrum modulation), frequency division multiplexing, and/or some other mechanism. The forward link, for example, may define (i) a pilot channel on which the RAN may broadcast a pilot signal to allow WCDs to detect wireless coverage, (ii) system parameter channels (e.g., a sync channel) on which the RAN may broadcast system operational parameters for reference by WCDs so that the WCDs can then seek network access, (iii) paging channels on which the RAN may broadcast page messages to alert WCDs of incoming communications, and (iv) traffic channels on which the RAN may transmit bearer traffic (e.g., application data) for receipt by WCDs. And the reverse link may define, for example: (i) access channels on which WCDs may transmit “access probes” such as registration messages and call origination requests, and (ii) traffic channels on which WCDs may transmit bearer traffic for receipt by the RAN.
In a conventional CDMA wireless network compliant with the IS-2000 standard, each cell employs one or more carrier frequencies, typically 1.25 MHz in bandwidth each, and each sector is distinguished from adjacent sectors by a pseudo-random number offset (“PN offset”). Further, each sector can concurrently communicate on multiple different channels, distinguished by “Walsh codes.” In doing so, each channel is allocated a fraction of the total power available in the sector. When a WCD operates in a given sector, communications between the WCD and the BTS of the sector are carried on a given frequency and are encoded by the sector's PN offset and a given Walsh code.
Wireless service providers typically design their wireless networks to comprise a number of partially-overlapping wireless coverage areas. As a WCD that is subscribed to a wireless service provider moves about, the wireless network may hand off the WCD from one wireless coverage area to another. A goal of performing such handoffs is to provide a substantially continuous wireless coverage to the WCD, so that any communication sessions conducted by the WCD are not dropped or degraded due to loss of wireless coverage. Further, to facilitate handoffs, a WCD may have an “active set” of coverage areas (e.g., sectors) that it can be handed off to.
In another aspect, for certain types of communication, such as voice calls, video calls, and/or other types of calls, a WCD may be able to use two or more different types of codecs when engaging in such communication. However, each codec may have different characteristics that impact the extent of resources used when the WCDs are communicating. | {
"pile_set_name": "USPTO Backgrounds"
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1. Technical Field
The present invention relates in general to disk drives and, more particularly, to a connector for a disk drive. Even more particularly, the present invention relates to an electrical connector for interconnecting a disk drive, a carrier for supporting the disk drive, and a docking bay into which the disk drive is inserted via the carrier.
2. Background Art
Hard disk drives (HDD) that are removable during operation in a computer or peripheral systems environment are sometimes referred to as xe2x80x9chot-pluggable.xe2x80x9d An HDD is typically mounted in a hard disk drive carrier prior to installation in a system. An HDD carrier is a frame-like structure which attaches to the HDD to assist in its insertion or removal from the system. HDD carriers also protect the HDD when it is outside of the systems environment. HDD carriers are typically constructed out of metal and/or polymeric materials.
The system contains several HDD""s, each of which may be readily interchangeable in the system. The HDD""s are mounted in bays in a chassis located within a system enclosure. The system typically has a drive connector and activity lights for each bay. Unfortunately, the connector and lights are usually located at the rear of the enclosure and are not visible once the HDD and carrier assembly is inserted into the bay. Thus, an apparatus and method for interconnecting a hot-pluggable drive in a system and monitoring the activity lights of the system while the drive is in operation is needed.
A carrier for a hot-pluggable disk drive has a frame with a pair of side walls, a front bezel, and a rear connector assembly. The disk drive mounts to the frame within its confines. The carrier also has pipes for transmitting light to the front bezel. The light pipes extend along the side wall from the front bezel to the rear connector assembly. The carrier is installed in the disk drive docking bay of a computer system. The rear end of the docking bay has a docking connector for interconnecting with the rear connector assembly, which also interconnects with the drive. The rear connector assembly is provided with a retainer for supporting the rearward ends of the light pipes. When the carrier is seated in the docking bay, the light pipes precisely align with activity lights at the back of the docking bay. The light emitted by the activity lights is transmitted through the light pipes and displayed at the front bezel for viewing by the user.
The foregoing and other objects and advantages of the present invention will be apparent to those skilled in the art, in view of the following detailed description of the preferred embodiment of the present invention, taken in conjunction with the appended claims and the accompanying drawings. | {
"pile_set_name": "USPTO Backgrounds"
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Combines are large self-propelled vehicles used for harvesting and threshing agricultural crop in the field. A harvesting head is typically disposed across the front of the combine vehicle supported on a feederhouse. This harvesting head is configured to cut and convey the crop into the combine vehicle itself where it is threshed, separated, and cleaned.
Traditional harvesting heads included an elongate rigid frame to which harvesting implements are added such as row units, reciprocating knife assemblies, augers, reels, and endless belt conveyors. One such type of harvesting head is called a “draper platform” or “draper”.
Draper platforms have an elongate frame on which are mounted left and right side endless belt conveyors mounted immediately behind a reciprocating knife. These endless conveyors convey cut crop material inward to a center portion of the draper platform, depositing them on a center conveyor that moves rearward. The center conveyor carries the material to and through an aperture at the rear of the draper platform frame, where it is deposited in an elevating conveyor called a feederhouse, which carries the cut crop material into the combine vehicle for threshing, separating and cleaning. Above the mentioned aperture at the rear of the draper platform frame, a rotationally driven, upper cylindrical conveyor drum with frusto-conical end sections and protruding fingers is usually provided for assisting the crop flow by undershot feeding.
The crop coming from the left and right endless belt conveyors thus needs to change its direction in the center of the platform from a lateral direction into a rearward direction. Under unfavorable circumstances, this area can be due to lack of moving feed elements between the rear end of the center conveyor and the upper conveyor drum subject to crop stalling, which allows crop to leak from the platform, causing crop losses and/or material to lodge in the left and right endless belts with the result of belt stalling. Both issues result in lost time and lost profits for the customer.
This problem is addressed by the arrangement described in the independent claim. Further advantages are provided by the dependent claims. | {
"pile_set_name": "USPTO Backgrounds"
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In recent years, sales for essential oils and other topically applied oils have exploded. Topically applied oils are usually oils which are derived from, or include certain essential components or essences of different substances. Such topically applied oils are generally referred to as essential oils.
Essential oils, known as nature's living energy, are the natural, aromatic volatile liquids found in shrubs, flowers, trees, resins, fruit peels, rhizomes, roots, bushes, and seeds. The distinctive components in essential oils defend plants against sects, environmental conditions, and disease. They are also vital for a plant to grow, live, evolve, and adapt to its surroundings. Essential oils are extracted from aromatic plant sources via steam distillation, cold pressing, and other types of distillation. Essential oils are highly concentrated and far more potent than dry herbs. Other topically applied oils may include olive oil, almond oil, coconut oil, etc. and oils high in esters, such as jojoba oil, and waxes such as beeswax.
While essential oils often have a pleasant aroma, their chemical makeup is complex and their benefits vast—which makes them much more than something that simply smells good. Historically, essential oils have played a prominent role in everyday life. With more than 200 references to aromatics, incense, and ointments throughout the Bible, essential oils are said to be used for anointing and healing the sick. Today, essential oils are used for aromatherapy, massage therapy, emotional health, personal care, nutritional supplements, household solutions, and much more.
Roller-ball applicators have been used in many applications. However, roller-ball applicators generally use a fairly pliable plastic housing to accommodate the ball in a press-fit assembly. Traditional roller-ball assemblies are unsuitable for use with most topical oils, such as essential oils, particularly citrus essential oils, and other similar oils with potent chemical solvents, because the oils tend to impregnate plastics and relax the elasticity, which often causes the roller-ball to become excessively loose and potentially dislodge. Additionally, essential oils tend to work as solvents with plastics and can leach unwanted chemicals and compounds from the plastics into the essential oils. Because of this, applicators for topical oils use different application methods and devices that do not require plastics that retain their material properties, and when using essential oils, avoid plastics altogether. | {
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The U.S. Pat. Nos. of Foote et al. 5,248,349, 5,372,646, 5,470,397 and 5,536,333, which are assigned to the assignee of the present invention and the entire disclosure of which is hereby incorporated by reference, disclose a continuous process for deposition of semiconductor material as a layer of cadmium telluride on a glass sheet substrate. The Foote et al. patents disclose source material troughs in which the cadmium telluride is received within a processing chamber that is heated. Glass sheet substrates are conveyed below the source material troughs such that sublimation of the source material from the troughs produces deposition of the semiconductor material on the upwardly facing surface of the conveyed glass sheets in a continuous manner. This construction requires that the source material troughs be periodically replenished with the cadmium telluride that provides the semiconductor material. The Foote et al. patent also disclose introduction of the source material as a vapor from sources of elemental cadmium and tellurium or from a source of cadmium telluride. | {
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Compact, high voltage capacitors are utilized as energy storage reservoirs in many applications, including implantable medical devices. These capacitors are required to have a high energy density since it is desirable to minimize the overall size of the implanted device. This is particularly true of an Implantable Cardioverter Defibrillator (ICD), also referred to as an implantable defibrillator, since the high voltage capacitors used to deliver the defibrillation pulse can occupy as much as one third of the ICD volume.
Implantable Cardioverter Defibrillators, such as those disclosed in U.S. Pat. No. 5,131,388, incorporated herein by reference, typically use two electrolytic capacitors in series to achieve the desired high voltage for shock delivery. For example, an implantable cardioverter defibrillator may utilize two 350 to 400 volt electrolytic capacitors in series to achieve a voltage of 700 to 800 volts.
Electrolytic capacitors are used in ICDs because they have the most nearly ideal properties in terms of size, reliability and ability to withstand relatively high voltage. Conventionally, such electrolytic capacitors include an etched aluminum foil anode, an aluminum foil or film cathode, and an interposed kraft paper or fabric gauze separator impregnated with a solvent-based liquid electrolyte. While aluminum is the preferred metal for the anode plates, other metals such as tantalum, magnesium, titanium, niobium, zirconium and zinc may be used. A typical solvent-based liquid electrolyte may be a mixture of a weak acid and a salt of a weak acid, preferably a salt of the weak acid employed, in a polyhydroxy alcohol solvent. The electrolytic or ion-producing component of the electrolyte is the salt that is dissolved in the solvent. The entire laminate is rolled up into the form of a substantially cylindrical body, or wound roll, that is held together with adhesive tape and is encased, with the aid of suitable insulation, in an aluminum tube or canister. Connections to the anode and the cathode are made via tabs. Alternative flat constructions for aluminum electrolytic capacitors are also known, comprising a planar, layered, stack structure of electrode materials with separators interposed therebetween, such as those disclosed in the above-mentioned U.S. Pat. No. 5,131,388.
In ICDs, as in other applications where space is a critical design element, it is desirable to use capacitors with the greatest possible capacitance per unit volume. Since the capacitance of an aluminum electrolytic capacitor is provided by the anodes, a clear strategy for increasing the energy density in the capacitor is to minimize the volume taken up by paper and cathode and maximize the number of anodes. A multiple anode stack configuration requires fewer cathodes and paper spacers than a single anode configuration and thus reduces the size of the device. A multiple anode stack consists of a number of units consisting of a cathode, a paper spacer, two or more anodes, a paper spacer and a cathode, with neighboring units sharing the cathode between them. Energy storage density can be increased by using a multiple anode stack configuration element; however, the drawback is that the equivalent series resistance, ESR, of the capacitor increases as the conduction path from cathode to anode becomes increasingly tortuous. To charge and discharge the inner anodes (furthest from the cathode) charge must flow through the outer anodes. With typical anode foil, the path through an anode is quite tortuous and results in a high ESR for a multiple anode stack configuration. By keeping the ESR low, however, the charge efficiency and DSR (delivered to stored energy ratio) of the capacitor are maximized.
The conduction path from the cathode to the inner anodes may be made less tortuous by providing pores in the outer anode foil. In this manner, charge can flow directly through the outer anodes to the inner anodes. Thus, the use of porous anode foil can combat the increase in ESR resulting from the use of a multiple anode stack configuration. U.S. Pat. No. 6,802,954 to Hemphill et al., incorporated herein by reference, describes an electrochemical drilling process for creating porous anode foil for use in multiple anode stack configuration electrolytic capacitors which produces a pore structure that is microscopic in pore diameter and spacing, allowing for increased energy density with a minimal increase in ESR of the capacitor. An etched foil is placed into an electrochemical drilling solution and a DC power supply is used to electrochemically etch the foil in the electrochemical drilling solution such that pores on the order of a few microns diameter are produced through the foil. The electrochemical drilling process creates large diameter “through” type tunnels, or pathways, in the foil that increase the electrical porosity of the foil, thereby improving charge efficiency and DSR. Aluminum Electrolytic Capacitors energy density is directly related to the surface area of the anodes generated in the electrochemical etching processes. Typical surface area increases achieved by etching can be 40 to 1 and represent 30 to 40 million tunnels/cm2. An electrochemical widening step is used to increase the tunnel diameter after etching to ensure that the formation of oxide will not close off the tunnels. Closing off of the tunnels during oxide formation will reduce capacitance and electrical porosity.
Adding Polystyrenesulfonic acid (PSSA) to the widening solution has been shown to improve the foil capacitance by protecting the foil surface form erosion and pitting, allowing the widening current to focus on the etch tunnel enlargement. However, the PSSA molecule has a tendency to combine with aluminum in the solution through flocculation that leads to inefficient use of the molecule to protect the surface during widening. Additionally after widening, the affinity of the PSSA to aluminum decreases the likelihood of efficiently removing the aluminum and PSSA from the tunnel structures. | {
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Tiles are typically held in place by cement, also known as mud, or other suitable adhesives, such as epoxy, mastic, and the like. Grout is a non-adhesive material that is applied between tiles to fill voids between adjacent tiles. Grout typically comprises a mixture of water, cement, sand, and may further include a color tint, and/or fine gravel. It is applied as a thick liquid and hardens over time, much like mortar. Grout is not flexible, and cannot expand and contract with changing temperatures.
To allow sufficient curing time for the adhesive, grout is usually applied at least fourteen to sixteen hours after the tiles have been set.
Excess grout must be removed as soon as application thereof is completed, as it is very difficult to remove excess grout from the surface of the tiles once it has cured. The most common procedure used to remove such excess grout from the surface of the tiles is to manually sponge off the excess material with a wet sponge; a procedure which is labor intensive and time consuming.
Other procedures and tools are known for use in removing excess grout from the surface of floor tiles. A common flat head screwdriver has also been used to scrape grout from tile surfaces. However, this method has drawbacks. Due to the small flat area provided at the tip of the conventional screwdriver, only a small amount of excess grout can be removed at a time.
Another tool in common use has a handle and stem resembling those of a screwdriver, but which terminates at its distal end with a metallic triangularly shaped scraper head. The terminal edge of the blade and corners of the triangle have utility in removing cement.
Another tool known as a grout/caulk packer is used in the manual process to form a concavity along the linear extent of the grout or caulk via a spherical member mounted at a distal end of a handle of the packer.
Another complex manual device used to remove excess grout comprises a wide blade adapted to remove excess grout and caulk, a four-armed cement remover and grout joint spacer, a spherical grout packer and a V-shaped grout and caulk profiler. These structures are adapted to be secured to a hollow handle of the device in varying combinations.
Another device includes a tile adhesive removal system having a handle provided with one or more removable tips. A properly-sized tip is selected for a particular channel width, and is removably attached to the handle. The tip removes any excess adhesive from the channel between tiles, and is then cleaned for use with the next tile. The removal system may include an orienting element, so that the tip is not inserted upside down.
Also, a brush for a rotary floor machine specially adapted to clean grout from tile surfaces has been proposed. The brush includes a disk having a plurality of bores arranged into a plurality of rings disposed about one face of the disk. Each ring defines an arcuate pattern of alternating first and second bores, with the first bores angled radially inwardly and the second bores angled radially outwardly. Tufts of bristles disposed within the first and second bores thus form areas of overlapping bristles.
Even though the above defined devices for applying grout to tiles or for cleaning grout from tile surfaces exist, a single-labor and time-saving grout installation and tile surface cleaning apparatus and method of use are still desired. | {
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1. Field of the Invention
The present invention relates to a fabrication method of a semiconductor device, and particularly to a fabrication method for forming plug electrodes as wiring between MOS field effect transistor (MOSFET) elements having gates, sources, and drains that are converted to a silicide with self alignment. The present invention further relates to a transistor fabrication method in which, when forming a diffusion barrier layer of a plug electrode material, which is wiring between MOS field effect transistor (MOSFET) elements, by a high-temperature sputtering method, the adhesion between a metal silicide film and the diffusion barrier layer of the plug electrode material is improved, and a diffusion barrier layer of a plug electrode material having highly uniform low resistance is formed.
2. Description of the Related Art
One method of fabricating a semiconductor device consists in forming a plug electrode as the wiring between MOS field effect transistor (MOSFET) elements. The procedures of this fabrication method are explained with reference to the sectional views of FIGS. 1A to 1F.
First, as shown in FIG. 1A, n-well 202 is formed in silicon substrate 201 by a known method. Field oxide film 203 is next formed by a selective oxidation method. Gate insulation film 204, for example, a silicon oxide film are made up by turn, and a polycrystalline silicon are successively grown on the active region that is surrounded by this field oxide film 203, and the polycrystalline silicon is doped with phosphorus by a known method to decrease the electrical resistance of the polycrystalline silicon.
The polycrystalline silicon is next patterned by the known methods of photolithography and dry etching to form gate electrode 205, as shown in FIG. 1A. Next, a low-concentration n-type impurity layer (not shown) and a low-concentration p-type impurity layer (not shown) are formed by photolithography and ion implantation. Side wall spacers 206 composed of a silicon oxide film or a silicon nitride film are next formed on the sides of gate electrode 205 using a known CVD method and an etching method.
A source-drain region of an n-type impurity layer and a source-drain region of a p-type impurity layer are next formed by photolithography and ion implantation. By these processes, n-type source-drain region 207 and p-type source-drain region 208 are formed as an LDD (lightly doped drain )structure.
Next, after removing the native oxide film (not shown) on the silicon substrate surface and on the surface of the polycrystalline silicon, which is the gate electrode, cobalt silicide film 209 is formed with self-alignment only over the gate electrode and diffusion layer according to a known method, as shown in FIG. 1B.
An insulating film such as a silicon oxide film is next grown using a known CVD (chemical vapor deposition) method, and the insulating film surface is then leveled using a known CMP (chemical mechanical polishing) method. The insulating film is next patterned using known photolithography and dry etching methods, and plug hole 210 is then formed for forming a plug electrode, as shown in FIG. 1C.
After cleaning the silicon substrate with, for example, a mixed solution of dilute sulfuric acid and hydrogen peroxide, the native oxide film (not shown in the figure) that has formed on the surface of the silicon substrate is removed by a known RF (radio frequency) sputtering method in an RF sputtering chamber which is attached to a sputtering device using plasma in which oxygen is mixed. At this time, a portion of cobalt silicide film 209 that is present at the bottom of plug hole 210 is etched as shown in FIG. 1D.
Titanium film 211 is next grown as shown in FIG. 1E by a sputtering method in an argon plasma atmosphere and under a heating condition of 300xc2x0 C. in a chamber of a sputtering device other than the above-described RF sputtering chamber. Still further, titanium is sputtered using a known reactive sputtering method under a heat condition of at least 300xc2x0 C. in a mixed argon-nitrogen gas plasma atmosphere to form titanium nitride film 212 on the silicon substrate. A Rapid Thermal Annealing process (RTA) is then carried out to form titanium silicide film 213 at the interface of titanium film 211 and cobalt silicide film 209.
After cleaning the silicon substrate with, for example, an aqueous mixed solution of dilute sulfuric acid and hydrogen peroxide, a tungsten film is grown using a known CVD method, following which the surface of the tungsten film is leveled using a known CMP method to form plug electrode 214 as shown in FIG. 1F.
The above-described method of fabricating a semiconductor device was employed to convert the polycrystalline silicon of a p-type electrode that had been doped with boron ions at a high concentration of 3xc3x971015 atoms/cm2 to cobalt silicide and then form a plug electrode above it. Subsequent measurement of the sheet resistance of the plug portion showed that the sheet resistance was at least 11 xcexa9/(unit area), and a comparison of the sheet resistance within the silicon substrate surface revealed a variation of at least 3 xcexa9. Similarly, a p-type diffusion layer electrode was converted to cobalt silicide and a plug electrode then formed above it. Subsequent measurement of the sheet resistance of the plug portion showed a sheet resistance of at least 11 xcexa9/(unit area), while a comparison of the sheet resistance within the silicon substrate surface revealed a variation of at least 6 xcexa9/(unit area).
The above-described method of fabricating a semiconductor device was also employed to convert the polycrystalline silicon of an n-type gate electrode on the silicon substrate that was doped with arsenic ions at a high concentration of 5xc3x971015 atoms/cm2 to cobalt silicide and then form a plug electrode above it. Subsequent measurement of the sheet resistance of the plug portion showed that the sheet resistance was at least 10 xcexa9/(unit area), and a comparison of the sheet resistance within the silicon substrate surface revealed a variation of at least 4 xcexa9/(unit area). Similarly, when a p-type diffusion layer electrode was converted to cobalt silicide and a plug electrode formed above it, subsequent measurement of the sheet resistance of the plug portion showed a sheet resistance of at least 10 xcexa9/(unit area), and a comparison of the sheet resistance within the silicon substrate revealed a variation of at least 4 xcexa9/(unit area).
In the above-described fabrication method of a semiconductor device, the sheet resistance of a plug electrode was high and the variation within the surface was large. It is therefore an object of the present invention to provide a fabrication method of a semiconductor device for forming on a silicide film a refractory metal film having lower resistance than the prior art.
As the result of continued research to realize a fabrication method of a semiconductor device that can achieve the above-described object of the present invention, the inventors of the present invention discovered that the increased sheet resistance of the plug portion and the large variation of sheet resistance within the surface both result from etching a portion of the metal silicide film by the RF sputtering method that is carried out immediately before growing the titanium film that is to serve as the diffusion barrier layer of the plug electrode.
As a result of further research, the inventors of the present invention also discovered that, in a case in which the titanium film is grown without carrying out the above-described RF sputtering method before depositing the titanium film that serves as the diffusion barrier layer of the plug electrode, a titanium silicide film is not formed at the interface of the titanium film and metal silicide film. As a result, the sheet resistance of the plug portion is further increased, variation within the surface becomes larger, and adhesion between the titanium film and metal silicide film is adversely affected, in some cases giving rise to exfoliation of the film.
According to the present invention, a method of fabricating a semiconductor device is provided in which, in a method of fabricating a semiconductor device in which a metal film, which is to serve as a diffusion barrier layer of an inter-element plug electrode of semiconductor elements, is formed over the entire surface of a silicon substrate using a sputter deposition method; wherein before the sputter deposition of the metal film, all portions of the substrate are covered by a photoresist except for portions of plug formation, following which silicon ions are implanted into the substrate, the photoresist is removed, and finally, the substrate is cleaned with a chemical fluid.
The present invention consists in implanting silicon ions in the bottom portion of a plug hole and then depositing a titanium film, which is to serve as the diffusion barrier layer of the plug electrode, whereby a titanium silicide film of low resistance is formed at the bottom of the plug hole without lowering the resistance of the plug electrode and without bringing about peeling of the film.
As for an explanation of this effect, silicon ions are implanted into the silicon substrate after etching the plug hole with the photoresist still in place. The photoresist is next removed and the silicon substrate is cleaned with a chemical fluid and then conveyed to a sputtering device. After growing a titanium film and titanium nitride film by a sputtering method, annealing is performed to form the plug electrode. The sheet resistance of the p-type gate electrode is compared for cases in which the surface etching process by a RF sputtering method is carried out or omitted immediately preceding the above-described titanium sputtering process.
Compared to a case in which surface etching is not performed, the sheet resistance for a case in which surface etching is performed by the RF sputtering method is approximately 10% higher, and the variation in sheet resistance within the surface is approximately 10% larger.
RF etching reduces the film thickness of the cobalt disilicide (CoSi2) film at the bottom of plug holes. Variation in plasma concentration within the silicon wafer surface is considerable when RF etching is carried out, and the thickness of the cobalt disilicide (CoSi2) film at the bottom of plug holes therefore also varies considerably within the wafer surface. As a result, the sheet resistance of the silicide film as a whole becomes high and variation in sheet resistance increases in cases in which the area of the open hole of a plug hole is large. As a result, resistance of the plug electrode increases and variation in resistance also becomes large.
If RF etching is not carried out, however, the thickness of the cobalt disilicide (CoSi2) film does not decrease and the sheet resistance of the silicide film does not become high.
To continue, a plug hole is etched, the photoresist is removed, the silicon substrate is cleaned with a chemical fluid, and the silicon substrate is conveyed to a sputtering device. The titanium film and titanium nitride film are next grown by a sputtering method, annealing is performed, and the plug electrode film is grown to form the electrode.
The shape of the silicon wafer is compared for a case in which the surface etching process is performed by an RF sputtering method immediately before the above-described titanium sputtering process, and for a case in which the surface etching process is not carried out.
In the case in which RF etching is carried out, despite long time heating of the wafer to grow a tungsten film by a CVD method for the purpose of forming a plug electrode, film exfoliation on the silicon substrate surface cannot be observed by the unaided eye and a good shape is maintained. In a case in which RF etching is not carried out, however, film peeling could be observed by the unaided eye in portions of the silicon wafer immediately following the above-described growth of tungsten. Even in cases in which film peeling did not occur, the resistance of the plug electrode in some cases increased markedly (for example, eight times the normal value) in portions of the silicon wafer.
Strong bonding is maintained between cobalt and silicon atoms in the cobalt disilicide (CoSi2) film at the bottom of a plug when RF etching is not carried out. When titanium and silicon react to form titanium silicide, however, the silicon atoms are reaction diffusion xe2x80x9cseeds.xe2x80x9d
Reaction between titanium and silicon therefore tends not to occur when RF etching is not carried out, and a titanium silicide film is therefore difficult to be formed.
Furthermore, cobalt that has undergone conversion to a silicide has a characteristic that impedes formation of an alloy with titanium.
The significance of the foregoing explanation is that little chemical bonding occurs between a cobalt disilicide (CoSi2) film and a titanium film, and adhesion between the two films is therefore extremely poor, and when a titanium film expands during the course of long-term heating, the titanium film therefore tends to peel away from the cobalt disilicide (CoSi2) film. Since a large force is also exerted on the overlying tungsten film, exfoliation of the entire structure tends to occur.
Exfoliation similarly occurs if RF etching is not carried out even in cases in which a titanium nitride film is grown directly on the cobalt disilicide (CoSi2) film. This state arises from the fact that the cobalt and silicon that form the cobalt disilicide (CoSi2) film tend to react with neither the titanium nor the nitride in the titanium nitride film.
In contrast, a portion of the bonds between cobalt and silicon that are present in the cobalt disilicide (CoSi2) film at the bottom of a plug are cut in the plasma atmosphere when RF etching is carried out, and titanium atoms and silicon atoms therefore tend to react relatively easily in the annealing that immediately follows sputtering, whereby a titanium silicide film having high adhesion with the cobalt disilicide (CoSi2) film, is formed. Adhesion between a titanium silicide film and a titanium nitride film is high, and exfoliation therefore does not occur.
In a case in which silicon ions are implanted immediately following hole formation of a plug hole by etching, exfoliation does not occur even if RF etching is not carried out. This state occurs because the cobalt disilicide (CoSi2) film at the bottom of a plug hole becomes non-crystalline due to the ion implantation, and a portion of the bonds between cobalt and silicon that are present in the film are cut, whereby titanium atoms react relatively easily with silicon atoms in the process of annealing that immediately follows sputtering, and a titanium silicide film having high adhesion with cobalt disilicide (CoSi2) film is formed. In addition, the amorphous cobalt disilicide (CoSi2) film is recrystallized during the annealing that immediately follows sputtering. Exfoliation therefore does not occur and resistance does not increase. | {
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In a related art, there is a well-known resistance-change type sensor that detects a change in resistance of a sensor element by a predetermined environmental change to measure a physical property of a target. A pressure sensor in which a so-called piezoresistance effect is utilized may be cited as an example of the resistance-change type sensor. In the piezoresistance effect, a resistance value is changed when a stress is applied to a physical body. The pressure sensor is widely used in various fields, for example, an in-car electronic device such as a sheet sensor and a consumer electronic device such as a blood pressure meter. Specifically, in this kind of resistance-change type sensor, as depicted in FIG. 21, a resistance value of a sensor element Rs is changed when an environmental change such as a stress is fed. A change in resistance ΔRS of the sensor element Rs is converted into a voltage by a current IO supplied from a current source 1, and an amplifier 2 amplifies the converted minute voltage ΔVs(=ΔRs×IO). The amplified output voltage VOUT (see the following equation) is supplied as a signal proportional to the environmental change to a subsequent-stage system (not depicted).VOUT=G×ΔVs=G×ΔRs×IO
where G is a gain of the amplifier 2. A rate of change of the change in resistance ΔRs with respect to the environmental change fluctuates according to a temperature. That is, the change in resistance ΔRs of the sensor element Rs has a predetermined temperature characteristic α. When the change in resistance ΔRs has the temperature characteristic α, the output voltage VOUT fluctuates according to the temperature characteristic α.VOUT=G×ΔRs×α×IO
Therefore, even in the same environmental change (for example, the same pressure change), the output voltage VOUT varies depending on an ambient temperature at that time. This causes an error.
For example, as disclosed in Japanese Patent Publication Laid-Open Nos. 03-200381 and 2007-097056, the temperature characteristic of the current IO supplied to the sensor element Rs is set to 1/α such that the temperature characteristic α of the change in resistance ΔRs is compensated, which allows production of the output voltage VOUT independent of the temperature characteristic α as follows.VOUT=G×ΔRs×α×IO/α=G×ΔRs×IO
The current having a temperature characteristic that compensates a signal gradient with respect to a signal having a temperature characteristic changed at a predetermined gradient to the temperature change is produced. Specifically, outputs of a plurality of constant current sources having different temperature characteristics are combined to change a gradient of the temperature characteristic of the constant current source, thereby producing the current having the desired gradient. Thus, in the circuits disclosed in Japanese Patent Publication Laid-Open Nos. 03-200381 and 2007-097056, when the temperature characteristic has the gradient that is linearly changed with respect to the temperature change, the temperature characteristic may be compensated (corrected). However, the temperature characteristic of the signal of the correction target may not simply increase or decrease, but sometimes the temperature characteristic is changed in a curved line with respect to the temperature change. For example, in the pressure sensor in which the piezoresistance effect is utilized, as depicted in FIG. 22, the change in resistance ΔRS of the sensor element Rs has the temperature characteristic α in which a high temperature side and a low temperature side of a predetermined temperature Ts differ from each other in the gradient due to an influence of a surface impurity concentration of the sensor element. Even in such cases, the circuits disclosed in Japanese Patent Laid-Open Nos. H03-200381 and 2007-097056 produce only the current having a temperature characteristic β (see alternate long and short dash line of FIG. 22) of the gradient linearly changed with respect to the temperature change. Therefore, a range on the low temperature side of a predetermined temperature T1 where the temperature characteristic α may not be compensated (corrected) is generated even if the gradient of the temperature characteristic β is freely adjusted. In the temperature range, because the influence of the temperature characteristic a may not be removed, the temperature characteristic α of the resistance-change type sensor becomes an error which causes detection accuracy to be lowered. Accordingly, in the complicated temperature characteristic in which the high temperature side and low temperature side of the predetermined temperature differ from each other in the gradient of signal change, it is preferable to produce the current whose temperature characteristic may be corrected with high accuracy.
The resistance-change type sensor is described above only by way of example. A similar problem is generated when the signal of the correction target has an unintended temperature characteristic. | {
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It has been suggested that the requirement for bandwidth in the public telecommunications network doubles about every two years ("Gigabit Networking on the Public Transmission Network", James A. McEachern, IEEE Communications Magazine, Vol. 30, No. 4, April 1992, pp. 70-78). The Synchronous Optical Network (SONET) OC-48 System (2.488 Gb/s) has been in service since 1992 which would imply that a bandwidth of 10 GB/s will be required by 1996 to meet demands. In the aforementioned article by James A. McEachern, it is indicated that in spite of current transmission rates in excess of 2 Gb/s less than 0.1% of the potential capacity of a single mode optical fiber is being exploited. The potential optical bandwidth available on single-mode fiber in the 1200 to 1700 nm low loss window is reported to be as much as 60 Tb/s.
Although bandwidths of up to 10 Gb/s have been demonstrated the practical upper limit of such a system has not yet been determined. Optical transmitters utilizing modulated lasers and optical modulators are capable of bandwidths to 10 Gb/s and beyond but other system elements such as optical detectors and electronic components are seen as potential limiting factors.
Since single-mode fiber has already been widely installed it follows from an economic perspective that it is advantageous to more fully utilize existing networks rather than routing additional fiber links. One method of more fully utilizing existing fiber while operating within the potential bandwidth limitation of 10 Gb/s is to deploy wavelength division multiplexing (WDM). By this process the bandwidth range within the low-loss window of 1200 to 1700 nm is partitioned into a plurality of discrete wavelength channels each potentially carrying a 10 Gb/s bandwidth. Each modulated wavelength carrier is multiplexed at the transmitter end and the composite signal is caused to propagate through the single-mode fiber. At the receiver end the composite signal is demultiplexed into the individual wavelength carriers and transferred to appropriate detectors.
A WDM access network may be established in at least two ways as shown in FIGS. 1A and 1B. According to the network of FIG. 1A, tunable lasers are employed to generate several discrete wavelength channels. Each wavelength channel is modulated by the external modulator and the individual, modulated channels are multiplexed into the fiber via the star coupler. At the receiver end the individual wavelength carriers are separated by preselected narrow band filters and read by photodetectors. The second network shown in FIG. 1B relies on fixed wavelength lasers to generate the wavelength carriers. These carriers are modulated by the external modulators and multiplexed into the fiber. At the receiver end a tunable filter is used to separate individual wavelength carriers.
Because optical fibers have a random polarization property the central carrier wavelength at the receiver end will include both transverse electric TE and transverse magnetic TM polarization modes. Generally, the wavelength selective coupling of the TE polarized mode in a directional coupler wavelength filter occurs at a longer wavelength than does coupling of the TM polarized mode. The difference in wavelength between the two modes can be 30 nm or more and hence an optical filter with a narrow bandwidth is unable to process both modes. | {
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Networks or network segments are often separated by network border control devices including session border controllers (S/BC). Network border control devices such as S/BC's are configured to control and secure delivery of control signaling and media information across separate networks or separate network segments. In some cases, a network service provider may use S/BC's to separate various network segments or two or more network service providers may use S/BC's to separate respective network segments. In such configurations, media communicated across two network segments has to traverse both an originating S/BC corresponding to an originating network or network segment and a terminating S/BC corresponding to another network or network segment. This is known as media anchoring because the media data must be communicated through (e.g., anchored through) the originating S/BC before being communicated to the terminating S/BC. Voice over Internet protocol (VoIP) communications are often subject to media anchoring. | {
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1. Field of the Invention
Jewelry boxes.
2. Description of Prior Art
Heretofore in displaying articles of jewelry, particularly in sets such as a finger ring and earrings to match, or cuff-links and a tie stud, the conventional practice has been to detachably mount the articles in fixed position on an upwardly exposed felt or like decorative display panel, in the bottom of a box so that the articles, when the box is open, are disposed in a position in which the decorative portions are fully displayed. The box, when closed, serves as a package for the articles. In other instances, the parts of a set are mounted on a display standard from which they are removed and packaged in a conventional jewelry box when sold to the customer.
In accordance with the present invention, a combined display and packaging box is provided in which provision is made for displaying one of the articles of the jewelry on the display panel in the bottom of the box in the customary manner, and for suspending one or more matching articles near the upper edge of the open cover of the box in a manner such that they can dangle and swing freely in overhanging relation to the panel when the box is open. When two matching articles are thus suspended and the cover closed, they can accommodate therebetween the article mounted on the panel. | {
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Computer generated graphics are commonly used in various areas of industry, business, education and entertainment. Computer graphics are represented by pixels on a display monitor. However, since the display only contains a finite number of pixels, aliasing may often occur. Aliasing due to having to represent analog data in a digital format, results in a displayed image appearing with jagged edges.
The application of techniques used to reduce aliasing is typically referred to as anti-aliasing. One technique used for full-scene anti-aliasing is known as supersampling. Supersampling is an approach in which an original graphics scene is rendered at a high resolution and subsequently filtered down to the original display resolution. Thus, supersampling essentially shifts the abasing effect up to a higher spatial frequency.
There are, however, performance drawbacks incurred by the computer system while using the supersampling technique. The problem with supersampling is that it requires additional processing and memory storage and bandwidth in order to render an image at higher resolutions, and later filter it down. For example, supersampling two times (2×) in each of an X and Y direction of the display requires four times (4×) the storage and bandwidth. Therefore, an efficient implementation of supersampling without incurring extra memory storage and bandwidth is desired. | {
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In the domain of WebRTC, there are many solutions developed in cloud environments. The main concern and consideration in these solutions is for optimizing for call quality, and routing media through the closest media relay points (closest being based on network topology and not necessarily geographically). In regulated industries or enterprises seeking higher security levels, compliance with regulations and corporate governance, the approach of existing solutions optimizing the call quality is not sufficient.
Existing solutions fail to consider scenarios where the speakers' call must be recorded and stored at a specific location or country, or when the sensitivity or context of the call needs to be governed or analyzed for specific content.
To that end, we have invented a new algorithm designed to work for routing media where more complex decision processes need to be used regarding relay and routing points. These decision processes need to take into consideration data retention, governance, regulation and call quality—as well as other aspects of the call. | {
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Present day telecommunications networks typically include a plurality of switching systems linked via transmission facilities (e.g., trunks and/or channels) that carry "calls" (in the form of voice, video or data) between switching systems. Additionally, these switching systems are typically linked via a signaling (data) network that transmits signaling messages between switching systems. Further, within a given telecommunications network, control information may flow between switching systems and databases, intelligent peripherals, or other specialized resources, as is well known in the art.
A present day switching system includes a switching fabric and a control mechanism as a single integrated system. The control mechanism of a switching system provides the intelligence to operate a specific switching fabric and some (or possibly all) of the intelligence required to interpret and respond to signals. The switching fabric includes devices for the termination of transmission facilities, as well as devices that provide multiple stages of space and time switching as is understood in the art. Additionally, the switching fabric may also include local intelligence, in the form of a processor or the like, for acting upon commands from the control mechanism. Within prior art switching systems, the control mechanism includes one or more special purpose computers that control such functions as connecting communications paths, and to varying degrees, receiving and sending signaling messages, performing operations, administration and maintenance functions, and providing call processing and customer services (e.g., service logic).
The switching fabric of present day switching systems controls call routing. In other words, the switching fabric, under control of its associated intelligence, makes decisions regarding trunk selection in order to transmit calls to another fabric of another switching system. Various techniques presently exist for routing calls and will not be discussed in detail. Examples of call routing techniques include Real-Time Network Routing (RTNR), Success to the Top Routing (STT) as well as Class-Of-Service Routing.
The nature of the switching fabric in present day switching systems is dependent on the nature of the calls carried by that fabric. For example, circuit-switch type switching systems typically utilize one type of fabric for carrying voice calls. In contrast, Asynchronous Transfer Mode (ATM) switching systems typically utilize a packet-type fabric for carrying data calls. Different types of fabrics route calls differently. Even though two different types of fabrics may utilize a particular routing technique, the implementation of that technique within one type of fabric is often necessarily different from its implementation in another type of fabric. Thus, when implementing a new routing technique, different implementations must be provided for different types of fabrics. As a result, development costs for implementing a new routing technique tend to be expensive.
Thus, there is need for a technique for achieving fabric-independent routing. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The invention, in general, relates to a novel method of controlling the movement of a laser engraving or printing head and, more particularly, to a method of controlling energization and discharge of a laser relative to its movement over a work surface to produce therein an undistorted image based on a bitmap.
2. Background of the Invention.
Apparatus utilizing a laser for engraving, or at least writing on, a suitable surface are well known. An example of such an apparatus is disclosed by U.S. Patent (Application No.: 09/508,739 filed Mar. 15, 2000) by Guettler and Penz. The apparatus functions by a tool head supporting a lens connected to a laser being moved relative to a work piece which is supported on a work surface and by periodically aiming pulses of collimated coherent light at the work piece to affect therein an image-wise surface alteration, by a plurality of indentations or pixels selectively placed so that together they form an image. The image may or may not be an inversion of a scanned or stored positive pattern or bitmap. The movement of the tool head may be responsive to signals, either directly or by way of a storage, derived from a device which mechanically or optically scans the pattern. The work piece may, for instance, consist of coated or anodized metals, paper, wood, or rubber etc. which is susceptible to the formation of indicia therein as a result of laser beam treatment.
The number of coherent light or laser beam discharges per inch of displacement of the laser tool head over the work piece and the duration of each pulse may be varied as an incremental position voltage as a function of the square root of the sum of the squares of the components of displacement of the tool head in orthogonal directions.
Basically, laser printing or engraving is carried out by line-scanning a bitmap and focussing a laser beam on a work piece, the laser beam being switched on at every image point (pixel) or off at every blank position, as the case may be, to form what for the sake of convenience may be referred to as a black and white image in the work piece. Gray-scale images are generated by changes in the intensity of the laser beam by modulating its pulse width. An encoder connected to the drive of the laser tool head provides position signals (pulses per angular unit) to a processor which in turn energizes the laser as a function of the pulses. Ideally, the laser is energized on the basis of a signal representative of the actual position of the tool head. The effect of any lag error, i.e. the difference between the desired and the actual position of the laser along a predetermined curve or line, may be insignificant and tolerable.
In processes of engraving rubber for fabricating stamps, a laser tool head may be moved at a velocity of about 30 cm/sec, and the maximum laser output power may not exceed 50 W. For engraving plastic tags or anodized aluminum, for example, the power output of lasers can generally be kept low as minimum power levels are required for the evaporation of anodized or plastic layers. Hence, the laser tool head may be moved at high velocities. In fact, apparatus is known wherein the laser tool head is moved at a velocity exceeding 1 m/sec. The quality of the resultant engravings have, however, been found to be wanting because of what appears to be an insufficient correction of the laser energization or compensation of the head velocity.
The problems inherent in bidirectional engraving processes in particular, are unfortunately readily apparent since pixels are directionally displaced, i.e. they are not aligned in precise vertical columns. In bidirectional engraving processes, the large time constant of the pulsed laser, at high velocities of the movement of the laser tool head, does in fact yield unusable results.
The difficulties inherent in energizing a laser render it difficult to provide high-speed engraving processes of acceptable precision with cost-efficient x-y plotters. The laser may be discharged at a rate of, e.g. of 500 ppi to form 500 pixels per linear inch of surface. In order to obtain an engraving of acceptable quality, the lag in energizing the laser as results from the physically and structurally conditioned response rate has to be adjusted as a function of the laser head velocity relative to the degree of plasma pre-ionization. Unless the lag is adjusted appropriately, a velocity of 1.5 m/sec of head movement and a laser energization period of greater than 100 xcexcsec lead to unacceptable errors greater than +/xe2x88x92150 xcexcm. This is thrice the empirical resolution of 50 xcexcm of the human eye.
It is a primary object of the invention to provide a method of coordinating the intermittent movement of a tool head and the periodic discharge of a laser relative to a signal derived from a scanned pattern or bitmap such that pixels are formed in a work piece so as to result in a distortion-free image.
A more general object resides in a method of line engraving on the basis of a bitmap from a suitable source.
A particular object of the invention is to provide a corrective algorithm for controlling the interaction between the high-velocity intermittent movement of a laser head and the related periodic discharge of the laser to yield engravings of superior quality.
Still another object of the invention is to provide a method of bidirectionally engraving pixels in the surface of a work piece by a laser such that each individual pixel of a pattern is shifted to compensate for the lag of response of the laser.
It is also an object of the invention to correct image points as a function of the instantaneous velocity of the movement of the laser head in accordance with a predetermined velocity profile.
Yet another object of the invention resides in compensating for the inherent lag of laser energization by tool head movement.
A still further object of the invention resides in a method of laser engraving wherein a laser is discharged as a function of a correctional laser head displacement signal.
Other objects will in part be obvious and will in part appear hereinafter.
In accordance with the above and other objects, the invention, in a preferred embodiment thereof, provides for shifting each pixel of an image so as to compensate for the lag in the discharge of the laser either on-line by a corrective process as a function of the instantaneous velocity or off-line on the basis of a preprogrammed velocity profile.
Preferably, the correction or compensation takes place during the acceleration path on the basis of an acceleration profile stored in the memory of a control device or on the basis of acceleration data collected by an encoder and fed to a control device. | {
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Field of the Invention
The present invention is directed to a columbarium system and method for interring cremated remains in individual niches or in a common vault using a single ossuary type repository.
Description of the Prior Art
As cost and space issues have led to fewer conventional burials and to a greater number of people choosing cremation, different systems have been developed for handling cremated remains, commonly referred to as cremains, in a dignified and respectful manner. Above ground columbarium systems have multiple storage compartments, commonly referred to as niches, which are able to store urns in a dignified secure manner and provide durability for withstanding exposure to weather for the extended times required. However, even costs of a columbarium having smaller storage spaces then traditional burials or crypts, may be too great, different options, especially less expensive options may be desirable.
Many columbaria are formed in a substantially cylindrical configuration with a layer of individual niches around an exterior of the columbarium with a center open space. This center space is typically not utilized and remains empty. However, the center space is typically protected from the elements by a capstone and the layer of exterior individual niches. The center interior volume provides suitable long term storage chamber for cremains if it can be accessed.
An ossuary provides for interring multiple separate cremated individual cremains in a single repository vault. Although an ossuary may use a common repository, it is still desirable to have a record of the individuals whose cremains are interred to provide a memorial of their final resting place. Therefore, it is desirable to provide a marker of each individual, preferably at or on the structure housing the cremains.
It can also be appreciated that delivery of the cremated remains to a common storage vault should provide for a respectful and dignified delivery of the remains into the vault. Such a delivery system should ensure that the remains cannot get caught to prevent clogs and/or incomplete delivery and should provide for security as well as being weather proof. Moreover, the delivery system should ensure that the cremains containers are evenly distributed in a common repository space.
Traditional urns may not be suitable for being dropped through a delivery system and landing in a vault with other remains. Traditional rigid urns may generate noise when landing in the repository and striking other urns. Moreover, there may also be a risk of the urn cracking or breaking open and/or releasing the cremains. Therefore, the discrete storage of each individual's remains should be configured for delivery to and interment in a common vault.
It is therefore seen that an improved interment system is needed that provides for delivery and permanent storage of cremated remains in a dignified and reverent manner. Such a storage system should provide a structure giving durable weather proof storage in individual niches or a shared repository. The system should also provide a proper record on the structure for the deceased who have been interred. Moreover, such a system should have a safe and reliable delivery system to the common repository that ensures substantially even distribution about the repository. The present invention addresses these as well as other challenges associated with interment systems for cremains. | {
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Homes, offices and other buildings have one or more systems of pipes that are configured to channel wastewater from the building to a sewer system or septic tank. In a common configuration, one or more toilets, sinks, bathtubs, and showers may be connected to a main waste line which is connected to a drain line or lateral that is then connected to a septic system or to a public sewer line. The lateral or drain line may have one or more cleanout valves that allow maintenance access to the lateral or drain line.
Unfortunately, the drain line or lateral may become clogged or backed up. For example, in systems where a drain line or lateral (or portions thereof, such as the portions exterior to a foundation of a building) is formed of terracotta or clay pipe, the line is susceptible to cracking, separation, disturbance or blocking due to tree roots, soil shifting or settling, or the like. A drain line or lateral may also become clogged or blocked when certain items (such as tampons) are flushed down a toilet. When a drain line or lateral (or portion thereof) becomes clogged, cracked or otherwise blocked, the sewage or wastewater that should drain out to the septic system or sewer system backs up into the house or building. Often, the clog may cause a backup and then wastewater may overflow into the building from its nearest open low point. Such overflows or backups can be unpleasant, unhealthy and expensive to repair. Further, many sewer system backups are not covered under a typical homeowner's insurance policy, nor are they covered by flood insurance.
It would be desirable to provide an alarm system that alerts or warns a homeowner (or other individual or entity) of the undesirable or unexpected pending presence of fluid in a pipe such as an upper lateral pipe or other outflow pipe. Several potential solutions have been proposed. For example, in U.S. Pat. No. 4,973,950, a sewer blockage alarm is described which utilizes a pressure sensor switch mounted to the inside of a cap for a sewer clean out branch. Unfortunately, the pressure sensor switch may provide inaccurate readings as a result of air or air bubbles collecting in the sewer clean out branch. Further, the '950 patent requires that a pressure bell extend into an interior of a pipe to be monitored which allows debris, sewage or other material collecting at the end of the pressure bell which, unfortunately can cause clogs or blockage.
U.S. Pat. No. 7,907,059 describes a similar alarm that is mounted in a cap of a pipe. The '059 patent requires the use of probes that extend into a pipe. Unfortunately, each of these systems requires that probes or other components extend to an interior of a pipe to be monitored which can lead to clogs or blockage. Further, these devices require the use of a drain clean out cap associated with a trap (e.g., in the '059 patent, an entire trap system is required to be retrofitted with the alarm). Most modern home or office fixtures (such as sinks, showers, toilets) have their own trap associated with it, making it undesirable to utilize drain clean out caps for use in positioning a monitoring device. Further, the inventor of the present invention has determined that placement of an alarm sensor device in a drain or cleaning pipe does not allow a pipe blockage to be detected sufficiently early enough to be corrected—instead, when a blockage is severe enough that wastewater is backing up to the cleaning pipe, a drain or other exit point (such as a toilet or the like), it is commonly too late for proactive maintenance action.
Canadian Patent No. 890926 (application number 1,261,940) describes a water backup alarm system which fits within a vertical pipe that leads to a sewer or septic system. The system is constructed of plastic material that fits entirely within a pipe. Unfortunately, installation of the system requires access to the interior of a pipe (such as, for example, through a cap or the like). Unfortunately, the system effectively reduces the interior dimensions of the pipe (which may result in blockage or obstruction of the pipe or a reduction in the capacity of the pipe). Further, the system requires that a user be able to access a section of pipe with a removable cap. Many homes or other buildings do not have drain systems with ready access to a suitable cap or section of pipe with a cap.
Accordingly, it would be desirable to provide a sewer alarm system which does not use a component which extends into the interior of a pipe being monitored. Further, it would be desirable to provide a sewer alarm system that is easily mounted or fitted on an existing drain line or lateral. Further still, it would be desirable to provide a sewer alarm system which does not substantially block or impair the flow of wastewater through the drain line or lateral. | {
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1. Field of the Invention
The present invention relates to an oil pump attachment structure for an engine and more particularly, it relates to an oil pump attachment structure for attaching an oil pump coaxially driven by a crankshaft.
2. Description of the Related Art
As an earlier structure for attaching the oil pump coaxially driven by the crankshaft, there is disclosed an attachment structure where a pump housing is carried inside a front cover for covering a timing chain and disposed between the front cover and a sprocket for a timing chain (Japanese Patent Publication No. 5-059924).
There is also another structure where a pump housing is disposed between the sprocket for the timing chain and a cylinder block, while the pump housing is either projected from the cylinder block for fixture or embedded in a recess formed on a front side of the cylinder block.
However, in case of the attachment structure allowing the front cover to carry the pump housing, the pulsation produced when operating the oil pump directly oscillates the front cover to cause the noise to radiate from the front side of the front cover, so that the engine noise is increased on the front side of the engine disadvantageously.
In case of the structure where the pump housing is disposed between the sprocket for the timing chain and the cylinder block, the running line of the timing chain is apart from the front face of the cylinder block due to the provision of the pump housing. Therefore, the driving force of the timing chain is applied on a camshaft's portion having a large overhang from journals supporting a camshaft while the whole length of the cylinder head is increased. Consequently, there is a possibility of causing the damping performance to be deteriorated due to the reduced rigidity of the camshaft and the journals or causing the weight of the cylinder block to be increased in order to ensure the rigidity of the camshaft and the journals.
In case of the structure where the pump housing is embedded in the front side of the cylinder block, there is produced a problem of causing the cylinder block to be large-sized. | {
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The use of nickel coated graphite particles was taught by Badia et al in U.S. Pat. Nos. 3,753,694 and 3,885,959. The nickel coated graphite particles provided improved machinability and wear resistance to aluminum castings. However, the process of Badia et al has disadvantages resulting from nickel coated graphite being dispersed throughout the aluminum casting. The graphite particles lower strength and related properties throughout the aluminum-base casting. Optimally, graphite particles are only placed at surfaces where increased wear and machinability properties are desired to minimize negative effects arising from graphite.
An additional technique for improving wear resistance of aluminum alloys is disclosed in U.S. Pat. No. 4,759,995 of Skibo et al. Skibo et al teach dispersion of SiC throughout aluminum castings. The SiC particles do not degrade strength properties as much as graphite. However, the process of Skibo et al also has disadvantages. The extremely hard surface of a SiC composite does not hold lubricant well or provide intrinsic lubrication properties. Thus, as a result of SiC composites poor ability to hold lubricant, SiC particles may actually increase unlubricated wear rate.
Another related technology for improving wear resistance relates to pressure injection molding or squeeze casting a preform constructed of a combination of carbon fibers and alumina fibers. The pressure injection method is disclosed by Honda in U.S. Pat. Nos. 4,633,931 and 4,817,578. According to the method disclosed in Honda, a combination of carbon and alumina fibers are dispensed and formed into a preform and placed into the desired area of the casting, i.e. on the inside of a cylinder wall of an internal combustion engine. The desired features of Honda's process are that it provides both a hard phase (Al.sub.2 O.sub.3) for improved wear properties and carbon fiber for improved unlubricated wear properties. Furthermore, any degradation in strength is isolated to regions of the casting containing the fiber proform. However, the process disclosed by Honda requires a pressure of about 20 to 250 MPa applied to molten aluminum metal to infiltrate the preform of alumina and carbon fiber. This high pressure requirement causes the price of pressure injecting a preform to be very expensive.
It is the object of this invention to provide a low pressure method for producing a localized mixture of hard wear resistant particles and a lubricating carbon phase at the wear surface of a light metal casting. | {
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The present invention relates to an electroluminescent device driving circuit used in exposure systems of matrix type electroluminescent display devices and electronic type printing apparatuses. In particular, the present invention relates to a circuit structure of an electroluminescent device driving circuit using amorphous silicon (a-Si) as the semiconductor layer of a film transistor for driving an electroluminescent device. | {
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In tooth decay, also known as dental caries, the enamel and thereafter the dentine are etched away until the internal pulp is reached. Eventually the tooth may die. Caries appear to be caused by acid released when bacteria in the mouth utilise carbohydrates such as sucrose. Examples of the bacteria involved include Streptococcus spp.
It is possible to reduce the incidence of caries by regular exposure of the teeth to fluoride ions. Such ions react with the enamel and render it more resistant to etching by acid. However, there is a strong feeling in the UK and elsewhere that it is not right to enforce mass medication on the population by addition of fluoride to water supplies.
It is accepted that regular cleaning of the teeth can lead to a more healthy dentition. A further way of lessening the chance of tooth decay is to reduce the carbohydrate intake, especially the amount of sucrose in the diet. For this reason there is a growing market for artificial sweeteners which can replace the sucrose and are non-cariogenic (i.e. do not cause caries).
It is important at this stage to distinguish between non-cariogenic and anticariogenic behaviour. A substance is non-cariogenic if it does not contribute to the incidence of caries. Thus, for example, low-calorie sweeteners such as saccharin are non-cariogenic. Low-sugar foodstuffs and related products containing these sweeteners cause less tooth decay because, for the same sweetness, their content of cariogenic material has been largely substituted by the non-cariogen.
A substance is anticariogenic, on the other hand, if it can reduce the cariogenicity of a product by virtue of the addition of the substance to the product. Anticariogenic substances can thus help avoid the need to lower the carbohydrate content of a product in order to lower its cariogenicity.
West German Offenlegungsschrift No. 2700036 is described the use of a group of chlorodeoxysucrose derivatives as artificial sweetening agents. This group comprises sucrose derivatives of the general formula ##STR2## in which R.sup.1 represents a hydroxy group or a chlorine atom;
R.sup.2 and R.sup.3 respectively represent a hydroxy group and a hydrogen atom, a chlorine atom and a hydrogen atom, or a hydrogen atom and a chlorine atom, the 4-position being the D-configuration; PA1 R.sup.4 represents a hydroxy group; or, if at least two of R.sup.1, R.sup.2, R.sup.3 and R.sup.5 represent chlorine atoms, R.sup.4 represents a hydroxy group or a chlorine atom; and PA1 R.sup.5 represents a hydroxy group or a chlorine atom; PA1 provided that at least one of R.sup.1, R.sup.2, R.sup.3 and R.sup.5 represents a chlorine atom. PA1 1. 1'-chloro-1'-deoxysucrose PA1 2. 4-chloro-4-deoxy-.alpha.-D-galactopyranosyl-.beta.-D-fructofuranoside [ie 4-chloro-4-deoxygalactosucrose] PA1 3. 4-chloro-4-deoxy-.alpha.-D-galactopyranosyl-1-chloro-1-deoxy-.beta.-D-fruc tofuranoside [ie 4,1'-dichloro-4,1-4,1'-dideoxygalactosucrose] PA1 4. 1',6'-dichloro-1',6'-dideoxysucrose PA1 5. 4-chloro-4-deoxy-.alpha.-D-galactopyranosyl-1,6-dichloro-1,6-dideoxy-.beta .-D-fructofuranoside [ie 4,1',6'-trichloro-4,1',6'-'-trideoxygalactosucrose] PA1 6. 4,6-dichloro-4,6-dideoxy-.alpha.-D-galactopyranosyl-6-chloro-6-deoxy-.beta .-D-fructofuranoside [ie 4,6,6'-trichloro-4,6,6'-trideoxygalactosucrose] PA1 7. 6,1',6-trichloro-6,1',6'-trideoxysucrose PA1 8. 4,6-dichloro-4,6-dideoxy-.alpha.-D-galactopyranosyl-1,6-dichloro-1,6-dideo xy-.beta.-D-fructofuranoside [ie 4,6,1',6'-tetrachloro-4,6,1',6'-tetradeoxygalactosucrose] PA1 9. 4,6,1',6'-tetrachloro-4,6,1',6'-tetradeoxysucrose. PA1 R.sup.6 is a hydroxy group or, if at least one of R.sup.4.alpha., R.sup.4.beta. or R.sup.1' is a chlorine atom, then it is a hydroxy group or a chlorine atom; PA1 R.sup.1' is a hydroxy group or a chlorine atom; and PA1 R.sup.6' is a hydroxy group or, if at least one of R.sup.4.alpha., R.sup.4.beta. or R.sup.1' is a chlorine atom, then it is a hydroxy group or a chlorine atom. PA1 (i) Saline, negative control for endogenous metabolism PA1 (ii) Sucrose, positive control PA1 (iii) 6,1',6'-trichloro-6,1',6'-trideoxysucrose, compound no. 7. PA1 (iv) Compound no. 7 plus sucrose. PA1 (v) 1',6'-dichloro-1',6'-dideoxysucrose, compound no. 4 PA1 (vi) Compound no. 4 plus sucrose PA1 (vii) 4,1',6'-trichloro-4,1',6'-trideoxygalactosucrose, Compound no. 5. PA1 (viii) Compound no. 5 plus sucrose PA1 (ix) 4,6,6'-trichloro-4,6,6'-trideoxygalactosucrose, Compound no. 6 PA1 (x) Compound no. 6 plus sucrose PA1 (xi) 1'-chloro-1'-deoxysucrose, compound no. 1 PA1 (xii) Compound no. 1 plus sucrose
The hope was that these compounds could be used to replace at least part of the sucrose in the diet, and thereby act as non-cariogenic materials.
Particular examples of compounds of the above general formula (I) are as follows (the systematic name is given first, followed by a trivial name using "galactosucrose" in those cases where an inverted 4-chloro substituent is present):
Unexpectedly, I have now found that not only do compounds such as the compounds no. 1 to no. 9 appear to fulfil the hope of non-cariogenicity, but also they exhibit an anticariogenic effect when retained in the mouth.
More specifically, I have found that there is a group of chlorodeoxysucroses which can reduce the amount of acid produced by mouth bacteria and which can reduce the adhesion of bacterial cells to dental surfaces. | {
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Typically, a wafer comprising a plurality of semiconductor dice are mounted on an adhesive film during singulation wherein each individual die is separated while it adheres to the adhesive film. Detaching and picking up of a die from an adhesive film is thus a common process involved in die bonding and flip chip bonding processes for assembling an electronic package. One trend for the development of high density electronic devices is to multiply its density on the same footprint by stacking up the dice comprised in an electronic package. The thickness of each die being stacked in the package has to be reduced in order to minimize the final height of the package.
It becomes a challenging task to detach a die from an adhesive film without damaging the die when the thickness of the die is reduced to below 4 mils (about 100 microns). Dice with thicknesses of 3-4 mils (75-100 microns) have been used for mass production for some time. Mass production of dice at 2-3 mils (50-75 microns) thick is currently under preparation. Experiments for research and development in electronic packaging designs are ongoing for dice of 0.8-2 mils (20-50 microns) thick. Hence, an apparatus that is capable of reliably detaching very thin dice from adhesive films is becoming a critical machine in the realm of electronic assembly equipment.
Typically in a die bonding process, a die is detached and picked up from an adhesive or dicing film by ejecting and pick-up tools before the die is transferred to a substrate such as a lead frame, a printed wiring board (PWB) substrate or a surface of another die in stacking die applications. In a die pickup process, a designated die on a dicing film is aligned with an ejecting tool with push-up pins which raises the die from the underside while the dicing film is held down by vacuum suction. A collet or a pick-up tool is then positioned just above the top surface of the partially detached die while the die is being lifted from the dicing film when the push-up pins rise to an appropriate level. The collet provides vacuum suction to hold the die during the detachment process, as well as transfers the detached die from the dicing film to a bonding substrate.
There are various forms of die detachment and pick up tools for facilitating detachment of a die from a dicing film to which it is mounted. The conventional tools include a needle-type ejector pin design, which is a traditional design for detaching a small die from a dicing film. Other forms of detachment tools are pyramidal-type detachment tools and slide-type detachment tools.
FIG. 1 is an illustration of a conventional die detachment and pick-up tool 100 with needle-type ejector pins 102. The die detachment part of the tool 100 has an ejector comprising an ejector chuck 104, ejector pins 102 and an ejector cap 106. The pick-up part of the tool 100 has a collet 108 mounted on a collet body 109 and positioned above a die 110 located on a dicing film 112 which is in contact with an upper platform surface 107 of the ejector cap 106. Vertical movement of the ejector chuck 104 is driven by a motorised mechanism. The ejector pins 102 are positioned on top of the ejector chuck 104 and are movable with the ejector chuck 104. For small dice of dimensions such as 2×2 mm2, a single ejector pin 102 positioned at the center of the die 110 to be detached suffices to detach the die 110. Multiple ejector pins 102 are preferred for larger dice, and the ejector pins 102 are evenly distributed to achieve a uniform push-up force on the die 110 so as to reduce a pinching effect by the ejector pins 102.
The ejector chuck 104 and ejector pin/pins 102 are positioned within the ejector cap 106. A vacuum channel 114 is enclosed by the ejector cap 106 in order to provide vacuum suction for aiding in the delamination of the die 110 from the dicing film 112.
When the thickness of a die is reduced to less than 100 microns, the die becomes less rigid. To detach a die, peeling energy is applied to the die being detached via push-up motion of ejector pins and the vacuum suction on the dicing film in order to overcome a critical interfacial adhesion strength between the die and a dicing film. Deformation of the die may arise due to the pinching effect by the ejector pins and the bending of the die. When the applied peeling energy reaches the critical interfacial adhesion strength, the die may be detached from the dicing film. However, the die will crack or break when the process of deformation of the die also reaches the critical strength of the die. The critical strength of the die depends on various characteristics of the die, such as the material of the die, wafer thinning, pattern on the surface of die and sawing of the die. For conventional die pick-up using ejector pin or pins, the pinching effect and bending deformation are affected by the number, arrangement and geometry of the ejector pins. Furthermore, for a large die, the ejector pins located at the periphery of the die inhibit propagation of the detachment to the center of die. Therefore, a conventional pick-up tool using ejector pins may not be suitable for detaching a thin die from a dicing film.
The pyramidal-type detachment tool includes a plurality of annular connection members to detach a semiconductor chip from a dicing film by stages; from an outer circumferential portion of the semiconductor chip towards a central portion of the semiconductor chip. The annular connection members are sequentially raised commencing from an outer connection member to a central connection member to form a pyramidal shape. Like the conventional needle-type detachment tool, the raised annular connection members in a pyramidal shape apply stress to the semiconductor chip which may crack or damage as a result of the stress. For this reason, it may also be undesirable to apply the pyramidal-type pickup apparatus for the separation of a thin semiconductor chip from a dicing film.
The slide-type detachment tool includes a slide that moves from side to side and attracts a semiconductor chip by vacuum suction so that the semiconductor chip is separated from a dicing film. Since the slide forms a vacuum while the slide moves from side to side, the distance through which the slide is configured to move increases when the size of the semiconductor chip increases. Also, productivity is low when using the slide-type pickup detachment tool due to the low moving speed of the slide.
Examples of prior art for thin die detachment applications are highlighted as follows. US Publication Number 2007/0228539A1 entitled “Method For Detaching A Semiconductor Chip From A Foil And Device For Mounting Semiconductor Chips” discloses a method for detaching a chip from a dicing film such as a foil using a ramping surface with a stripping edge and ejector pins. The stripping edge is next to a groove area with the ejector pins. When detaching a die, the stripping edge moves up the surface of an ejector cap while vacuum suction is applied to the said ejector cap. The detached semiconductor is curved to form a concave shape when it is transported to the stripping edge by the movement of a wafer table. The detached chip is pushed to the groove and is picked up by ejector pins. A disadvantage of this detachment tool is having to move the wafer table to the stripping edge. In order to move the wafer table, vacuum suction force that is applied between the dicing film and the surface of the ejector cap must be low as the vacuum suction force would drag and distort the wafer. A lower vacuum suction however reduces the applied peeling energy. Furthermore as the detachment of the die is not on a controllable stage, the die may flip. Also, in the final pick-up stage, ejector pins are used which as discussed above are not suitable for picking up thin die.
US Publication Number 2002/0129899A1 entitled “Die Pickup Method And Die Pickup Apparatus” discloses a movable plate which may move horizontally or in both a horizontal plane and a vertical direction to detach a die from a dicing film. The shortcoming for this method is that there is no supporting structure underneath the die being picked when the movable plate is moved to detach the die. This may cause the die to crack at locations where the die is not detached. Additionally, neighbouring dice surrounding the die being picked are affected by the movable plate.
US Publication Number 2008/0092360A1 entitled “Thin Semiconductor Chip Pickup Apparatus and Method” discloses a die detachment apparatus with a stage for supporting a dicing film. An advantage over the movable plate discussed above is that the die detachment process is faster and the neighbouring dice are also not affected by the detachment process. However, this apparatus involves the motion of a suction member along a vertical axis at a level below the surface of the ejector cap which means the die is not pushed up very much away from the ejector cap. Furthermore, the initial detachment requires a dicing film to conform to the initial lowering of the suction member by applying suction vacuum. This greatly limits the applied peeling energy to the die being detached. Therefore, it would be desirable to achieve an effective method of detaching thin chips which provides support to the chip and reduces the pinching effect on the chip while avoiding the disadvantages of the prior art as discussed above. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to the recording of information on film and particularly to the production of negative or positive film transparencies useful in the production of proof copies or for imaging printing plates.
2. Description of the Prior Art
Recently, many systems for imaging printing plates with laser beams have been proposed. U.S. Pat. No. 3,964,389 to John O. H. Peterson, which is herein incorporated by reference, discloses a method of making an imaged printing plate using a transparent substrate coated with (a) particles which absorb laser energy, (b) a self-oxidizing binder, and (c) a cross-linking agent or a cross-linking agent in combination with a cross-linkable resin. The coated side of the substrate is placed in intimate contact with a lithographic printing surface and subjected to a laser beam directed through the transparent substrate which by writing in the configuration of an image selectively transfers portions of the coating to the lithographic printing surface. The transferred coating is then rendered durable by heating the binder or resin to cross link it.
The transferred coating leaves a clear area on the transparent substrate which corresponds to the image areas on the lithographic printing surface. The laser-imaged transparent film thus constitutes a negative transparency of the image produced by the laser beam on the plate. Such a negative transparency is useful as a mask in the production of proof copies or for imaging conventional photo lithographic printing plates.
The Peterson patent discloses the use of carbon black particles in the coating to absorb laser energy. The Peterson coating can be transferred to the lithographic printing surface satisfactorily with acceptable laser power requirements, but more coating residue may be left behind on the transparent film than desirable for forming good negative masters. Increasing the power of the laser or slowing down the writing speed leaves less residue behind, but this is undesirable for obvious reasons. | {
"pile_set_name": "USPTO Backgrounds"
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Many woodworking operations, particularly cutting finger joints, slots, and decorative trims, require precise location of the cut, especially for tightly-fitting adjacent components. Plunge routers are widely used by woodworkers in order to accomplish such precisely located cuts in manufacturing fitting joints, slot mortising, horizontal boring, and over-arm routing operations.
Router tables are also widely used because of their ability to make more precise cuts than can be made by hand. A router table is typically a horizontal work surface under which a conventional router may be mounted in order to use it as a shaper by moving a workpiece relative to the router bit, rather than moving the router bit relative to the workpiece. Often, such router tables are inconvenient to use because adjustment of router bit position must be accomplished by adjusting the router on its base, which is difficult to do with the router mounted upside down underneath a router table.
In some types of woodworking, such as mortise and tenon work, it is desirable to allow universal variation of the main table and router bit with respect to the workpiece. To maintain the workpiece in position relative to the cutter bit, some prior art router tables are provided with elongated fences that are connected to the top of the main table so that they can be moved laterally toward and away from the cutter bit. In this type of arrangement, it may be cumbersome and potentially dangerous for a user to attempt certain horizontal end cuts while manually holding the workpiece against the fence in a position perpendicular to the main table.
Accordingly, it is desirable to provide a router table which allows safe and convenient positioning and securing of a workpiece in positions perpendicular to the main table while allowing simple and accurate adjustment of the router bit with respect to the workpiece. | {
"pile_set_name": "USPTO Backgrounds"
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Businesses are continually trying to improve the services that they provide to their customers. To better address their customer needs, businesses often provide “customer service departments.” These departments typically employ individuals (sometimes referred to as “agents” or “representatives”) who answer questions, inquiries, complaints and/or other sales and service issues. At a most basic form, an agent communicates with customers via a telephone to orally answer sales/service inquiries of customers who call the customer service department.
Customer relationship management (CRM) systems have become popular in recent years to automate interactions between businesses and customers. Using hardware and software, many tasks traditionally performed by agents may be performed electronically. For instance, customers may listen to prerecorded messages in automated voicemail systems (a form of CRM) and make menu selections using a telephone keypad.
However, businesses, products, and customers may vary greatly from one situation to another. What works very well for one business may not work as well for another. Given this, CRM systems are often customized for each business. This customization may be expensive and lengthy, involving several groups of individuals to provide to businesses with, for example, customized software code, customized hardware, customized applications, and the like.
For example, to allow a business to access client account information via the web, a web application customization may involve a web application developer, a web designer and a database application developer. The web application developer may be responsible for taking business requirements and for developing the complete web application. The web application developer may ask a web designer to create a user interface (UI) mock up.
The web application developer or the designer may be familiar with web development. Either may create files using hypertext markup language (HTML), Active Server Page (ASP) and/or JavaServer Page (JSP) scripting, for example. However, most web application developers and web designers are unfamiliar with the configuration of underlying database(s) and/or database application(s) (e.g. a CRM application) that may provide information and functionality relevant to the application. Therefore, a third group of developers, e.g. database application developers, often help create the custom application.
The database application developer may reconfigure database(s) and/or database application(s) to meet the specific business requirements. For example, a database application developer may configure and/or create templates, applets, repository views, business objects, business components, data services and network services. To accomplish these tasks, the database application developer is usually specially trained in skills specifically relating to a particular database and/or database application. For example, a Siebel® application developer may be trained to work with eScript/Siebel VB™, BrowserScript™, Siebel® object configurations and Siebel® templates.
Once the database(s) and/or the database application(s) are configured and useful interfaces or objects created, the database application developer may then communicate instructions to the web application developer on how to access the interfaces and/or objects. Using these interfaces and objects, the web application developer may create a front end (e.g. a GUI) to provide user access to the database.
This customization process may take weeks, if not months, causing delays in deployment of the application. For example, the web application developer may be unfamiliar with new and/or existing database application interfaces, as well as with the database(s) structure. This unfamiliarity may make it difficult to request the proper modifications. This unfamiliarity may also add development time to allow the web developer to learn how to access and interact with the interfaces in the application code. Even if a web application developer is familiar with the interfaces, the developer may have to write and debug code to create the proper custom application.
Also adding to deployment time is the database application developer's tasks of configuring the database application to support the custom application, e.g. modifying an existing feature, adding a feature, updating a component, installing components, or the like. Thus, what is needed is an improved system and method for generating a custom application. | {
"pile_set_name": "USPTO Backgrounds"
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Conventionally, when a customer calls a customer service representative, agent support system, and the like for various reasons, the call agent or agent phone support system has a combination of a phone and computer database interface to assist the caller by identifying the caller and reference account information to assist the caller.
As the types of customer subscriptions continues to evolve, the types of call agent services and call center services continues to evolve as well. For instance, a user calling a support center is often utilizing a smartphone with applications aimed at providing such support. Also, emails, short message service (SMS) messages and live calls are all available during a communication session. However, most services are limited to only one service communication medium at a time.
FIG. 1 illustrates a conventional prior art communication network configuration 100. Referring to FIG. 1, the consumer 102 may utilize a communication device 110, such as a phone, mobile phone, smartphone, Internet enabled computing device, tablet computing device, etc., to initiate a communication to a customer call center over a network or PSTN 130. The service provider 120 may be located at a remote service site managed by call database servers 124. The service agent 122 typically resides at a workplace location and answers a phone 123 as the calls and requests are received.
However, this approach does not enable multiple modes of communication to alleviate customer needs and to satisfy customer inquiries and concerns and to provide a far better customer experience by delivering requested and prescient information. | {
"pile_set_name": "USPTO Backgrounds"
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1. The Field of the Invention
The present invention relates to projectiles and, more specifically, projectiles including a non-discarding sabot for discharge from a rifled barrel.
2. Present State of the Art
Guns, such as hand guns and rifles, are designed to interact with a cartridge for discharging a projectile, commonly referred to as a bullet. A cartridge includes a metal case which houses a charge such as gun powder. Mounted at one end of the case is a primer. The projectile is crimped or otherwise secured to the opposing end of the case.
During operation, the cartridge is positioned within the chamber of a gun. By depressing a trigger, a hammer strikes against the primer. In turn, the primer ignites the gun powder which burns at an extremely fast and almost instantaneous rate. As the gunpowder burns, it produces a gas. The rapid expansion of the gas detaches the projectile from the case and pushes the projectile down and out the end of the barrel.
It has long been known that imparting an axial rotation to the projectile significantly improves the accuracy in which the projectile can be fired. Several approaches have been used to impart rotation to the projectile. The most common approach is to form a series of spiral grooves that longitudinally extend along the interior surface of the barrel. The projectile is configured to engage the grooves and thus rotate as the projectile travels the length of the barrel. Momentum allows the projectile to continue to spin after the projectile leaves the barrel.
Depending on the type of projectile used, different approaches have been used to engage the projectile and the grooves. For example, some projectiles are made from relatively soft lead alloys. During discharge, the force of the expanding gas causes the projectile to obterate and radially expand, thereby engaging the grooves. Where the projectile is made of a harder material, the projectile is configured having a diameter slightly larger than the inner diameter of the barrel. As a result, the projectile is forced into the grooves as the projectile travels within the barrel.
Although the operation of guns has become a refined science, there are still several shortcomings associated with conventional projectiles. For example, extended firing of a gun, such as commonly encountered in the military, results in pressure from the expanding gases wearing or deteriorating the interior surface of the gun barrel. Significant wear on the barrel occurs much earlier when hard projectiles are used. The resulting wear on the barrel can produce irregular flight paths in the projectile and can reduce the speed and distance which the projectile travels. In such cases, it is necessary to replace the gun or at least the barrel thereof.
The problem with using lead alloy bullets is that they produce lead build-up on the interior surface of the barrel. Lead build-up increases the resistance on the projectile and can radically increase pressures as well as offset the flight path of the projectile. One approach to solving this problem has been to use various cleaning materials to remove the lead build-up from the interior surface of the barrel. This cleaning process, however, requires the use of toxic solvents that produce a harmful lead waste.
Discarding sabots have been used as another approach to overcoming some of the above problems. A discarding sabot is simply a plastic jacket that is placed over the projectile. During firing, the expanding gas results in expansion of the projectile and sabot such that the sabot, rather than the projectile, engages the grooves of the barrel. By engaging the grooves, the sabot rotates which in turn imparts a rotational movement to the projectile. As the projectile exits the barrel, the sabot is caught by the surrounding air and peeled off of the projectile, allowing the projectile to freely travel. The discarding sabot thus eliminates and prevents the need for the metal projectile to engage the interior surface of the barrel. As a result, wear on the barrel is minimized. Furthermore, there is no metal fouling or buildup in the barrel.
Although sabots produce some advantages, conventional discarding sabots also produce significant problems. For example, as a discarding sabot leaves the barrel, it rapidly expands to release the projectile. In some instances, the sabot breaks apart resulting in a fouled bore. The discarding sabot can produce bore fouling. Specifically, the discarding sabot can clog or otherwise obstruct such systems as sound suppressors, flash suppressors, gas recoil systems, recoil reduction systems, and bore evacuators. Furthermore, if the sabot does not evenly release the projectile, the projectile can become imbalanced and subsequently tumble. | {
"pile_set_name": "USPTO Backgrounds"
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I. Field
The present invention relates generally to systems and methods for performing surgical procedures and, more particularly, for accessing a surgical target site in order to perform surgical procedures.
II. Description of Related Art
A noteworthy trend in the medical community is the move away from performing surgery via traditional “open” techniques in favor of minimally invasive or minimal access techniques. Open surgical techniques are generally undesirable in that they typically require large incisions and high amounts of tissue displacement to gain access to the surgical target site, which produces concomitantly high amounts of pain, lengthened hospitalization (increasing health care costs), and high morbidity in the patient population. Less-invasive surgical techniques (including so-called “minimal access” and “minimally invasive” techniques) are gaining favor due to the fact that they involve accessing the surgical target site via incisions of substantially smaller size with greatly reduced tissue displacement requirements. This, in turn, reduces the pain, morbidity and cost associated with such procedures. The access systems developed to date, however, fail in various respects to meet all the needs of the surgeon population.
One drawback associated with prior art surgical access systems relates to the ease with which the operative corridor can be created, as well as maintained over time, depending upon the particular surgical target site. For example, when accessing surgical target sites located beneath or behind musculature or other relatively strong tissue (such as, by way of example only, the psoas muscle adjacent to the spine), it has been found that advancing an operative corridor-establishing instrument directly through such tissues can be challenging and/or lead to unwanted or undesirable effects (such as stressing or tearing the tissues). While certain efforts have been undertaken to reduce the trauma to tissue while creating an operative corridor, such as (by way of example only) the sequential dilation system of U.S. Pat. No. 5,792,044 to Foley et al., these attempts are nonetheless limited in their applicability based on the relatively narrow operative corridor. More specifically, based on the generally cylindrical nature of the so-called “working cannula,” the degree to which instruments can be manipulated and/or angled within the cannula can be generally limited or restrictive, particularly if the surgical target site is a relatively deep within the patient.
Efforts have been undertaken to overcome this drawback, such as shown in U.S. Pat. No. 6,524,320 to DiPoto, wherein an expandable portion is provided at the distal end of a cannula for creating a region of increased cross-sectional area adjacent to the surgical target site. While this system may provide for improved instrument manipulation relative to sequential dilation access systems (at least at deep sites within the patient), it is nonetheless flawed in that the deployment of the expandable portion may inadvertently compress or impinge upon sensitive tissues adjacent to the surgical target site. For example, in anatomical regions having neural and/or vasculature structures, such a blind expansion may cause the expandable portion to impinge upon these sensitive tissues and cause neural and/or vasculature compromise, damage and/or pain for the patient.
This highlights yet another drawback with the prior art surgical access systems, namely, the challenges in establishing an operative corridor through or near tissue having major neural structures which, if contacted or impinged, may result in neural impairment for the patient. Due to the threat of contacting such neural structures, efforts thus far have largely restricted to establishing operative corridors through tissue having little or substantially reduced neural structures, which effectively limits the number of ways a given surgical target site can be accessed. This can be seen, by way of example only, in the spinal arts, where the exiting nerve roots and neural plexus structures in the psoas muscle have rendered a lateral or far lateral access path (so-called trans-psoas approach) to the lumbar spine virtually impossible. Instead, spine surgeons are largely restricted to accessing the spine from the posterior (to perform, among other procedures, posterior lumbar interbody fusion (PLIF)) or from the anterior (to perform, among other procedures, anterior lumbar interbody fusion (ALIF)).
Posterior-access procedures involve traversing a shorter distance within the patient to establish the operative corridor, albeit at the price of oftentimes having to reduce or cut away part of the posterior bony structures (i.e. lamina, facets, spinous process) in order to reach the target site (which typically comprises the disc space). Anterior-access procedures are relatively simple for surgeons in that they do not involve reducing or cutting away bony structures to reach the surgical target site. However, they are nonetheless disadvantageous in that they require traversing through a much greater distance within the patient to establish the operative corridor, oftentimes requiring an additional surgeon to assist with moving the various internal organs out of the way to create the operative corridor.
The present invention is directed at eliminating, or at least minimizing the effects of, the above-identified drawbacks in the prior art. | {
"pile_set_name": "USPTO Backgrounds"
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This application claims the priority of Japanese Patent Application No. 4-93772 filed on Mar. 19, 1992, which is incorporated herein by reference.
1. Field of the Invention
This invention relates in general, to an endermic liniment for the body which characteristically contains a fennel extract, and, more specifically, to an invigorating herbal gel for supple skin which is effective in increasing lipase activity and thus accelerating lipid metabolism.
2. Description of Related Art
In order to reduce excess fat in the body and thus maintain a well-defined body, various exercises and restrictive diets have been used and cosmetics gels and creams have also been used for body massage to accelerate internal metabolism. Thus far, however, no endermic liniment has been discovered with weight reducing effects which targets lipase, an enzyme which aids in lipid metabolism.
It is therefore an object of the invention to provide a substance which increases lipase activity in the body and thus accelerate lipid metabolism. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates generally to computer security and more particularly but not exclusively to methods and systems for redirecting data to a cloud scanning service.
2. Description of the Background Art
Data may be scanned for various reasons relating to computer security including to detect computer viruses, unauthorized transfer of sensitive data, communication with prohibited servers, violation of security policies, and other computer security threats. Scanning data to perform security checks is especially troublesome for private computer networks with a relatively large number of users because of the volume of traffic traversing the network. A private computer network may maintain an on-premise, i.e. within the private computer network, scanning device to scan all network traffic transferred between computers within the private computer network and computers on the Internet. However, on-premise scanning devices typically have a fixed feature set that needs to be continually upgraded to accommodate additional users. | {
"pile_set_name": "USPTO Backgrounds"
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Semiconductors devices such as memory devices reside in many computer and electronic products. Memory devices store data. Input data is stored into a memory device in a write operation. Output data is outputted from the memory device in a read operation.
Most memory devices have data (input/output) pins and data strobe pins. The data pins carry the input and output data to and from the memory device. The data strobe pins carry timing information of the data.
Some memory devices have two separate sets of data strobe pins: write data strobe pins and read data strobes pins. The write data strobe pins carry timing information of the input data. The read data strobe pins carry timing information of the output data.
In most cases, the write data strobe pins are unused during the read operation; and the read data strobe pins are unused during the write operation.
Leaving some pins unused in some operations wastes resources. | {
"pile_set_name": "USPTO Backgrounds"
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Numerous decaffeination techniques are known in the art. One widely practiced decaffeination method is disclosed in U.S. Pat. No. 2,309,092 to Berry et al. Green coffee beans are moistened and subsequently extracted with a caffeine-deficient green coffee extract, with the extraction typically taking place in a countercurrent extraction battery Caffeine-laden extract withdrawn from the extraction battery is then decaffeinated by contact with a caffeine solvent. While the method of Berry et al. is quite effective, it is only applicable to the decaffeination of green coffee beans and is not suitable for the decaffeination of extracts of roasted coffee.
The art has generally continued to progress along lines of decaffeination of green extracts. Relatively little progress has been made in technology looking toward the direct decaffeination of the extract of roasted and ground coffee. To be sure, certain patents like that to Adler et al., U.S. Pat. No. 2,933,395 issued Apr. 9, 1960, have offered to the art workers the approach of decaffeinating the extract of roasted and ground coffee; but such arts have not materially advanced until recently to the point of providing a brew quality equal to or exceeding that recoverable by decaffeination of green beans.
Thus, techniques are known for decaffeinating roasted coffee extracts, but the methods are not without certain drawbacks. Belgian Patent Disclosure No. 865,488 of Bolt et al. describes a process in which roasted coffee extract is first decaffeinated with the solvent, the solvent is then contacted with water to transfer the caffeine and unavoidably some non-caffeine solubles, the decaffeinated solvent is returned to the coffee extract and subsequently stripped therefrom; and the caffeine is crystallized from the water phase, which is then discarded. The water phase unavoidably contains an amount of noncaffeine solubles which would contribute important flavor notes but which are instead discarded. The particular flavor notes which are lost with the discarded water phase are the "body" notes which contribute to the overall balance of coffee extract flavor. Without these body notes, the coffee extract and the soluble coffee made therefrom are typically characterized as weak and thin.
A similar decaffeination method is disclosed in U.S. Pat. No. 4,409,253 to Morrison et al. The improvement is said to be in recycling the water phase from which the caffeine has been crystallized back to the incoming caffeinecontaining extract. It appears that the water phase cannot be combined with the decaffeinated extract because of the substantial amounts of caffeine remaining in the water after crystallization. This inefficient recycling of the water phase, with the corresponding increase in the amount of caffeine to be removed, would appear to increase the volume of extract to be decaffeinated, inflating operating costs.
Accordingly, it is an object of the present invention to provide an efficient method for decaffeinating aqueous roasted coffee extracts.
Another object of the invention is to provide a method of decaffeinating aqueous roasted coffee extracts which minimizes the amount of flavor notes lost during decaffeination.
Such improvements as have been noted in the production of decaffeinated extract produced from roasted and ground coffee leave much to be desired from the standpoint of flavor. It would be desirable to provide a decaffeination process which uses roasted and ground coffee, instead of green; is relatively applicable to current processing techniques; and yields a product that can match or exceed the quality extracts derived from decaffeinated green beans. The present invention relates to just such a product. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to a gas supplying apparatus for supplying high pressure gas flowing from gas containers to chemical processing apparatus by reducing said gas pressure.
Moreover, this invention relates to a vapor-phase growth plant comprising a dopant gas conduction means for supplying high pressure dopant gas flowing from dopant gas containers to vapor-phase growth apparatus by reducing said dopant gas pressure.
2. Description of the Prior Art
A well known prior art gas supplying apparatus is configured such that chemical processing gas, filled as compressed gas or liquefied gas in a gas container or gas cylinder, is supplied through piping system via pressure reducing valve to chemical processing apparatus.
FIG. 4 illustrates the schematic configuration of a vapor-phase growth plant as an example of such conventional gas supplying apparatus.
According to the drawings, the vapor-phase growth plant has a gas supplying container(or gas cylinder) 61 which is filled up with dopant gas (for example, H.sub.2 diluted B.sub.2 H.sub.6 : diborane gas) 62. The dopant gas flows through a dopant gas supply piping 64 via a pressure reducing valve 63 to a thin film growth chamber 65a disposed in a vapor-phase growth apparatus 65. In the thin film growth chamber 65a, the dopant gas is supplied on a substrate which is loaded in the chamber for growing thin film by vapor-phase growth on the surface of the substrate.
For the purpose of removing any contaminants in the dopant gas supply piping 64 which may intrude from surroundings, a gas purging apparatus is connected to the dopant gas supply piping 64. The gas purging apparatus is equipped a purging gas supplying conduit 66 and a purging gas discharge conduit 67 respectively therewith.
As for purging gas, nitrogen gas (N.sub.2) or rare gas (Ar, He etc.) are adopted. The part which is closed by a dotted line in the FIG. 4 shows cylinder cabinet 68 for storing the gas supplying container 61.
As shown above, in the prior art, the cylinder cabinet 68 is disposed on one-for-one correspondence to the vapor-phase growth apparatus 65. The reason for this is that a gas supplying container commonly used, as usual, has some variance in dopant gas concentration. Therefore, upon replacing of the dopant gas supplying container, dopant gas concentration may vary for some extent, which may result in variance on atomic concentration of the grown thin film produced in the vapor-phase growth apparatus 65, though operated in the same situation or the same film growing condition.
In consequence, to avoid undesirable variance of dopant concentration in the grown thin film caused by replacing the dopant gas supplying container, thin film growth condition by the vapor-phase growth apparatus must be adjusted respectively in accordance with the dopant gas concentration of each dopant gas supplying container.
However, since the cylinder cabinet 68 is disposed on one-for-one correspondence to the vapor-phase growth apparatus 65 in the conventional vapor-phase growth plant, the following problem arise:
(1) As the number of vapor-phase growth apparatus 65 increases, the number of cylinder cabinet 68 must be increased, which results in the increase of plant installation cost. PA0 (2) In order to avoid variance in grown thin film quality (dopant concentration) upon replacing of gas supplying containers, the production condition must be adjusted, which result in the lesser productivity because of the increase of adjusting time. PA0 (3) Upon replacing of gas supplying containers, such troublesome operations as the substituting of residual gas in the dopant gas supplying pipe with the purging gas would be required. PA0 (4) Ever since the gas supplying container is rather small in volume, duration on continuous operation is short. | {
"pile_set_name": "USPTO Backgrounds"
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Increasingly, people would like to utilize mobile devices in commercial and information-seeking transactions. Recently, texting via short messaging service (SMS), alternately referred to as “simple message service,” has become a popular format for social and commercial communications. However, limitations imposed by the SMS protocol sometimes hamper dissemination of rich details in SMS texts. Therefore, the current practice of sending multiple text messages to communicate more in-depth information sometimes fails to provide a satisfying user experience. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to frequency sweeps, and, more particularly, to a multi-arm frequency sweep generator operating at radio frequency.
Many communication devices utilize frequency sweeps, e.g., demodulators, swept receivers and spectrum analyzers. A frequency sweep is a waveform with a monotonic frequency function of time. Typically, linear frequency sweeps are desired.
Frequency sweeps can be generated by time dispersing a pulse as a function of frequency. The pulse is selected to have frequency components over the desired output range of the sweep.
A reflective array compressor (RAC) is one device used to produce such dispersion. The RAC may be manufactured by etching plural slits in a large quartz crystal. The size and placement of the slits determine the dispersion characteristics of the RAC. For example, a RAC can be designed to provide a linear or other specific sweep. RACs are well-known in the art and are described for example in "The Use of Surface-Elastic Wave Reflection Gratings in Large Time-Bandwidth Pulse Compression Filters", R. C. Williamson et al, I.E.E.E. Transactions on Microwave Theory and Techniques, Vol. MTT-21, No. 4, April, 1973, pp. 195-205.
In one application, a surface acoustic wave (SAW) demodulator can incorporate three or three sets of RACs. The input to the demodulator can be a frequency division multiple access (FDMA) signal. For each symbol or bit period of the FDMA signal, a first or input RAC time-staggers the individual frequency bands that make up the multiplexed signal. A second frequency sweep RAC converts pulses, synchronized to the input bit periods, to sweeps. The sweeps are combined with the staggered frequency channels to produce a series of sweeps. A third or output RAC compresses these sweeps into pulses which represent the time division multiplexed (TDM) decoding of the FDMA input.
While RACs perform quickly and reliably, they are difficult to manufacture precisely. A RAC designed to produce a linear frequency sweep, for example, will generally have some characteristic non-linearities. The cost of manufacturing each RAC typically prohibits large scale rejection of deviating devices. In addition, the characteristics of a RAC can change due to temperature. For RACs to be used in environments such as space with temperature extremes, it is desirable to be able to calibrate a RAC to maintain linearity.
In many applications, an error signal can be obtained which when zeroed indicates a linear frequency sweep. More specifically, a sweep can be applied to a known input signal, and the result compared to the expected output. In the SAW demodulator described above, a constant known input should produce a series of pulses with very little spreading. Any spreading can be analyzed as a function of frequency to identify points of non-linearity in the frequency sweep and allow for correction.
However, in applying corrections device encounter performance constraints which limit the slope and repetition rate of sweeps that can be corrected reliably. Device technology continues to ease these limits, but desired objectives remain distant. What is needed is an approach that can greatly extend the frequency slopes and repetition rates that can be reliably corrected with current technology. | {
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Various classes of block diagrams describe computations that can be performed on application specific computational hardware, such as a computer, microcontroller, FPGA, and custom hardware. Classes of such block diagrams include time-based block diagrams, such as those found within Simulink®, from The MathWorks, Inc. of Natick, Mass., state-based and flow diagrams, such as those found within Stateflow®, from The MathWorks, Inc. of Natick, Mass., data-flow diagrams, and software diagrams, such as those found in the Unified Modeling Language.
Historically, engineers and scientists have utilized time-based block diagram models in numerous scientific areas such as Feedback Control Theory and Signal Processing to study, design, debug, and refine dynamic systems. Dynamic systems, which are characterized by the fact that their behaviors change over time, are representative of many real-world systems. Time-based block diagram modeling has become particularly attractive over the last few years with the advent of software packages, such as Simulink®. Such packages provide sophisticated software platforms with a rich suite of support tools that makes the analysis and design of dynamic systems efficient, methodical, and cost-effective.
A dynamic system (either natural or man-made) is a system whose response at any given time is a function of its input stimuli, its current state, and the current time. Such systems range from simple to highly complex systems. Physical dynamic systems include a falling body, the rotation of the earth, bio-mechanical systems (muscles, joints, etc.), bio-chemical systems (gene expression, protein pathways), weather and climate pattern systems, etc. Examples of man-made or engineered dynamic systems include: a bouncing ball, a spring with a mass tied on an end, automobiles, airplanes, control systems in major appliances, communication networks, audio signal processing, nuclear reactors, a stock market, etc. Professionals from diverse areas such as engineering, science, education, and economics build mathematical models of dynamic systems in order to better understand system behavior as it changes with the progression of time. The mathematical models aid in building “better” systems, where “better” may be defined in terms of a variety of performance measures such as quality, time-to-market, cost, speed, size, power consumption, robustness, etc. The mathematical models also aid in analyzing, debugging and repairing existing systems (be it the human body or the anti-lock braking system in a car). The models may also serve an educational purpose of educating others on the basic principles governing physical systems. The models and results are often used as a scientific communication medium between humans. The term “model-based design” is used to refer to the use of block diagram models in the development, analysis, and validation of dynamic systems.
In designing models of modern systems, the size of the models is being increased to a stunning level of complexity. Hundreds of thousands of components may be included in the models. In order to manage the complexity of the models, the technologies of hierarchy, abstraction, and partitioning are utilized. The hierarchy is typically captured by so-called ‘subsystems.’ Because subsystems may contain their own subsystems, they provide a mechanism for the hierarchical structure of the models. Abstraction allows dismissing system behavior in the models if it is not important to the problem that needs to be addressed and for which the models are designed. Including arbitrary detail often complicates and hampers the design, analysis, and/or synthesis of the model. Partitioning is used to create separate and independent modules (or ‘units’) in the models. The partitioning facilitates engineers to work on engineering projects where each engineer (or a group of engineers) is responsible for one unit of the models. The aforementioned technologies may help design models that have a high level of complexity. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of Invention
The present invention relates to a monitoring method. More particularly, the present invention relates to a hard disk system state monitoring method.
2. Description of Related Art
A server or a large-scale computer system generally comprises lots of hard disk to meet the requirement of large amount of data storage. Backplane and the expander are the devices design for connecting multiple hard drives with multiple device slots. However, in such a complex hard disk system, the user has to manually establish the relation between the hard disk addresses and the device slots, which is a time-consuming process. Further, in order to monitor the hard disk system to make the data access more efficient, it's necessary to build a real time monitoring mechanism.
Accordingly, what is needed is a hard disk system state monitoring method to establish a real time database of the hard disks automatically to perform the monitoring mechanism. The present invention addresses such a need. | {
"pile_set_name": "USPTO Backgrounds"
} |
The present invention relates to a method for manufacturing an optical fiber preform and an apparatus therefor which can manufacture optical fibers exhibiting a reduced transmission loss caused by hydroxyl groups in the region of wavelengths between 1280 nm and 1600 nm.
Hydroxyl groups that are present in glass used in forming optical fiber cause absorption in the wavelength vicinity of 1385 nm, which is one of the causes of transmission loss of the optical fibers.
For this reason, conventionally, a dehydration step has been used in the process for manufacturing an optical fiber preform to reduce hydroxyl groups contained in optical fiber preforms, as taught in Japanese Patent Application, First Publication No. S57-17433.
This dehydration method includes placing a porous glass preform obtained by vapor-phase deposition methods, such as the VAD method or the OVD method, in a dehydration apparatus; supplying a dehydrating agent containing a chlorine-based compound gas, such as Cl2, SOCl2, or CCl4, to this dehydration apparatus; and heating the optical fiber preform at about 1000° C.-1300° C. to remove water absorbed in the porous glass.
However, the effect of dehydration by this conventional dehydration method may be insufficient, and an improvement thereof has been desired.
Such improvements include, for example, methods disclosed in Japanese Patent Application, First Publication No. H11-171575 and Japanese Patent Application, First Publication No. 2002-187733.
However, these methods have shortcomings and are less practical since these methods require special equipment, such as a plasma etching apparatus, for example, or these methods make it difficult to manufacture a large optical fiber preform, or these methods entail complex operating conditions.
Furthermore, other than the above-identified technique, there are a number of related art patents relating to such a dehydrating treatment of optical fiber preforms, including those disclosed in U.S. Pat. No. 6,131,415 and U.S. Patent Application, Publication No. 2002-0073741.
Accordingly, the present invention provides a method for manufacturing an optical fiber preform and an apparatus therefor which can reduce hydroxyl groups in an optical fiber preform to a sufficient level without requiring any special equipment or operating conditions. | {
"pile_set_name": "USPTO Backgrounds"
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Storage tanks of flammable liquids, such as petroleum products are commonly grouped or clustered together in an area referred to as a "tank farm". Should one of the tanks become ruptured and the contents become involved in a fire, huge quantities of heat are generated. The heat generated in the fire radiates into the surrounding tanks and their contents.
The radiated heat weakens anearby tank's outer shell and creates internal pressures, especially as the tank's contents rise in temperature. Then the rise in temperature makes the tank more vulnerable to rupture.
The most common fire fighting technique is to cool the external shell of any surrounding tanks in the tank farm which might be susceptible to extreme heat.
The most frequent cooling technique conducted is to spray large quantities of water on the tank shel. The cooling water (fire stream) is sprayed directly under high pressure onto the side of the tank.
However, the high pressure water hits the tank with such force that the wate immediately bounces back off the face of the tank. As a result, the water is in contact with the tank skin for only a short time and is very inefficient in transferring heat because of this limited contact with the tank skin.
Moreover, the fire fighter must position himself as directly as possible between the tank that is on fire and the tank that is to be cooled. Such as position is necessary in order for the fire fighter to direct his cooling water (fire stream) directly at the face of the tank skin that is receiving most of the radiated heat from the tank that is on fire.
Some of the prior provides the following references:
U.S. Pat. No. 1,220,106, Hartenberger, Mar. 20, 1917 PA1 U.S. Pat. No. 2,955,686, Blomeley et al, Oct. 11, 1960 PA1 U.S. Pat. No. 2,994,383, Gorand et al, Aug. 1, 1961 PA1 U.S. Pat. No. 4,044,517, Schroter, Aug. 30, 1977 PA1 U.S. Pat. No. 4,177,863, Simon, Dec. 11, 1979 PA1 GB No. 2,000,022, Winkler, Jan. 4, 1979 PA1 WIPO No. 83/01200, Sobrinho, Apr. 14, 1983
U.S. Pat. No. 1,220,106 to Hartenberger describes a wooden silo having a double wall construction comprising an inner lining and an outer sheathing constructed so that there is a space between them to provide for free circulation of air from air inlet doors in the bottom of the silo upwardly to an exit space provided in the conical roof of the silo.
U.S. Pat. No. 2,955,686 to Blomeley et al described a double-walled insulating structure for gasoline, fuel oil, chemicals, and similar products. In the enclosed space between the two walls, insulating material is inserted to be held in place by a series of supporting members and distance members. The insulating material, such as fiberglass or the like, also fills the space provided in the domed roof which is secured to the walls.
U.S. Pat. No. 2,994,383 to Gorand et al describes a fire protection system for an elevated structure, such as a tower, vessel, or building. The system includes a fixed nozzle, mounted generally at ground level, attached to a high pressure water system, and directed at a "chute", or water receiving member. The chute has an enlarged water receiving inlet and a restricted water outlet. The water outlet of the chute is connected to a water distribution pipe which receives the water which had been directed into the chute and permits the water to exit the pipe through a series of opening in the pipe so that water will be distributed over the surface of the elevated structure.
U.S. Pat. No. 4,044,517 to Schroter describes a tank jacketing system for a cylindrical tank comrpising a series of circular track components to which are attached individual panel members, vertically attached and with each panel member insulated with a rigid insulating member adhesively attached to the inner side of the panel. The arrangement is for heat-protecting the storage tank. The panel members and wall of the storage tank are loosely secured at the top of each by a coping disposed over the exterior of the insulating wall and innermost upper portion of the wall of the storage tank.
U.S. Pat. No. 4,177,863 to Simon describes a safety liquid dispenser which provides a combination a double walled tank body comprising an intermediate container of flammable liquid and an inner tank disposed within the intermediate container and containing pressurized carbon dioxide positioned to smother any flame condition occurring within the tank.
GB No. 2,000,022 to Winkler describes a fire-resistant container for combustibles comprising a double-walled container with the space between the walls filled with fire-extinguising material.
WIPO No. 83/01200 to Sobrinho describes a trough-like collar affixed to an upper external rim of a fuel tank which includes a plurality of overflow holes. A water supply pipe is in position to supply water to the trough of the collar from which the water may exit the holes and flow down the side of the tank. | {
"pile_set_name": "USPTO Backgrounds"
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