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A planetary steering differential which has been particularly effective for continuously driving the opposite output members of a track-type tractor at equal speeds for straight-ahead operation, or at different speeds for steering operation is disclosed in U.S. Pat. No. 4,434,680 issued Mar. 6, 1984 to C. W. Riediger, et al. However, the planetary steering differentials disclosed in that patent are not as compact as desired, and have a number of assembly, disassembly and serviceability disadvantages. One disadvantage resides in the orientation of the steering motor and associated input pinion on a horizontal, transverse axis. With such orientation, the steering motor is relatively inaccessibly located within the vehicle case and it is difficult to service it or the associated hydraulic lines connected to it. One solution to this resides in mounting the steering motor in a radial orientation external to the vehicle case as is disclosed in U.S. Pat. No. 4,557,157 issued Dec. 10, 1985 to E. D. Oestmann. But while the steering motor is accessible in that solution, major portions of the steering differential are added to the vehicle case through different openings so that considerable service time is required for assembling or disassembling the remainder thereof.
Another disadvantage with the steering differential of U.S. Pat. No. 4,434,680 is that the planetary steering differential is partly assembled or disassembled within the vehicle case by a mechanic leaning through an access opening. Still another problem is that it is difficult to disconnect the opposite axle shafts in order to allow removal of the planetary steering differential located therebetween.
Accordingly, what is needed is a compact planetary steering differential having a radial orientation of the steering motor at an external accessible location, and an efficacious mounting arrangement for rotatably supporting the elements of the planetary steering differential so that the majority thereof can be handled as a modular assembly capable of being easily connected to the vehicle frame. Specifically, it is preferred that the two bevel gear and pinion sets thereof be preadjusted in an effective manner as a subassembly before installation on the vehicle.
The present invention is directed to overcoming one or more of the problems as set forth above. | {
"pile_set_name": "USPTO Backgrounds"
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Heretofore, in most article packaging operations, a plurality of manual operations have been required and usually the articles to be packaged will vary widely in number, weight and volume so that in businesses that ship a variety of products, a plurality of different sizes of preformed shipping containers are required. This number of different shipping containers can be extremely large when a variety of packages and articles are being shipped, and a large inventory of different size boxes, containers or container blanks is required and the particular shipper enclosure is manually selected for size and than has the articles to be shipped manually placed therein. Furthermore, an appreciable amount of storage space is required for the large number of packaging units, shipping containers or boxes that must be stored and appreciable inventory costs are incurred in these prior packaging operations.
Manual operations of a repetitive nature in packaging operations can be quite costly as well as being tedious to perform. Hence, any automation that can be provided in packaging actions is quite desirable while any reduction in inventory costs and storage space provides savings of packaging costs. | {
"pile_set_name": "USPTO Backgrounds"
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It is known in the art relating to accessories for automobiles to provide storage compartments within the vehicle. In the past, storage compartments have been located in various different areas of an automotive vehicle. One location is the glove box in the instrument panel area of the vehicle. Other locations have included armrests with storage compartments, side pockets of doors and overhead consoles. Some vehicles include floor consoles located between the seats of a vehicle which also include storage areas for miscellaneous items. These compartments take up valuable space such as headroom, floor height and wheel well space. Also, some of these compartments may "advertise" that something is hidden from view, thus drawing attention to hidden items and inviting theft. There is a need to provide a large storage area in a vehicle that does not draw attention to itself and invite theft. | {
"pile_set_name": "USPTO Backgrounds"
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Field of the Invention
The present invention relates to machines for automatically manipulating small liquid samples in a chemical analysis setting. More particularly, it relates to improvements in sample carousels and the use of these carousels in combination with improved pipette tips for transferring liquid to or from these carousels. | {
"pile_set_name": "USPTO Backgrounds"
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In recent years, technologies for combining a computer graphic (CG)-drawn image with a captured image of the real world photographed with a camera or the like by a photographer using CG and displaying the combined image on a display device have been developed. In particular, technologies, which combine photographed individual imaging data of the real world with CG image data registered (set) and designated in advance, have been popularized.
As known technology information in this field, for example, there is a technology disclosed in Non-patent Document 1.
Non-patent Document 1 describes a method of combining a virtual object with a video of the real world by measuring the 3-dimensional position and the posture of an object using markers disposed at apexes of a parallelogram.
Patent Document 1 manifests a mixed reality display device and method, a storage medium, and a computer program. Specifically, a CG image can be combined with an image photographed with a camera, and is displayed by installing a design-drawn marker or a blinking LED light source at a specific place of the real world. Thus, for example, a simulation of a scene in which a piece of furniture installed in a specific place in the real world can be viewed on a display device. This demonstrates an application of the mixed reality display method as a disposition simulation in a real world space of furniture or an electronic appliance.
Patent Document 2 shows a portable augmented reality device and method and describes an embodiment in which the above-described display system is applied to a portable game device.
Patent Document 3 shows an entertainment device, system, and method and discloses an embodiment in which a die-shaped object is used as the above-described proper object.
Patent Document 4 describes a target position search device, a target position search method, and a program. This patent document is an earlier filed patent application technology and describes a search display system of an individual, a target facility, or the like by AR (Augmented Reality).
Specifically, a graphic indicating the position of a target object is combined with a real video and is displayed based on a display method using a simple graphic without execution of discrimination by a search target. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to delay discarding sabot projectiles which are well known in the field of ordnance and may be defined as a discarding sabot projectile comprising in part a subcaliber core or projectile coacting with a full caliber pusher (sometimes referred to as a carrier) and including further means for delaying the axial separation between the pusher and the projectile until the assembled pusher/projectile has been shot from the muzzle of a rifled gun barrel and traveled a predetermined distance from the muzzle. A delay discarding sabot projectile is used as ammunition for automatic guns carried on aircraft. It is important, to prevent damage and/or destruction to the aircraft, to keep the pusher/sabot/projectile assembly intact until the assembly is a safe predetermined distance ahead of and/or away from the aircraft, whereat the pusher and projectile axially separate with the penetrator continuing its trajectory and with the parts of the carrier and sabot following a predictable flight to the ground without risk of collision with the aircraft from which the assembly was fired.
A significant problem with prior art delay discarding sabot projectiles has been difficulty in maintaining predictability of the time of separation, i.e., the distance traveled by the assembled pusher/sabot/projectile from the aircraft before the axial separation of the pusher and the penetrator. Those skilled in the art recognize that the pusher has relatively high aerodynamic drag. Thus, the relatively high velocity of the full caliber pusher and assembled projectile at the time of ejection from the gun barrel immediately begins diminishing as the assembled pusher/detonator/penetrator travels through the air. If the axial separation between the pusher and the penetrator occurs too quick or early, i.e., prior to the desired separation point, then there are two adverse results. The first is, as aforesaid, the debris of separation, i.e., the metal pusher and/or discarding sabot may strike the delivery aircraft, e.g., being ingested into the engines or otherwise causing harm and possible destruction to the aircraft. The second problem associated with early axial separation of the pusher and the penetrator is that the penetrator (following separation) will have a higher velocity than planned or intended and accordingly will probably miss the target, i.e., will probably overshoot the target. If the axial separation between the pusher and the penetrator occurs too late, i.e., after the desired separation point, then the assembled pusher/penetrator will have decreased substantially in velocity so that the penetrator velocity, after separation, will be too slow and the penetrator will fall short of the intended target.
Thus, a key object of this invention is to provide an improved delay discarding sabot projectile having significantly increased hitting accuracy by accurately controlling the time/distance from the aircraft of the actual axial separation between the pusher and the penetrator, a collateral object being to provide a safe apparatus so that there will not be danger for the delivery aircraft all as aforesaid.
Prior art delay discarding sabot projectiles has typically taken the form of a metal pusher having a forward facing recess surrounding a high density metal penetrator, both pusher and penetrator typically being right circular cylindrically shaped members. The prior art pusher typically had a pyrotechnic delay column and expulsion charge adapted to explode after the assembled pusher/penetrator has been ejected from the gun barrel so as to axially separate the penetrator from the pusher. The inherent problem with the prior art configuration was that there could, because of normal machining/manufacturing variations, be significant differences in dimensions between the outer diameter of the penetrator and the inner diameter of the aforesaid recess. The difference in dimensions vary from round to round and hence result in a substantial variation of release forces, i.e., the forces tending to hold the penetrator within the pusher. This uncontrollable variation in release force accordingly would dramatically and significantly change the separation point from one round of ammunition to another, greatly reducing the overall accuracy, i.e., failing to produce a projectile having a low dispersion factor. My invention has solved this problem in a unique manner, i.e., producing a projectile that can be made on a low cost mass production basis and having a very high accuracy, i.e., a low dispersion factor. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of Invention
This invention relates generally to the packaging of golf balls, and more particularly to a multi-module golf balls sleeve for packaging a set of golf balls to create separable modules each housing an individual ball which may be pushed out of the module.
2. Status of Prior Art
The game of golf involves hitting a small hard ball whose outer white spherical casing has an array of dimples formed therein. The ball is hit with specially made clubs or irons over an outdoor course, called links. The full complement of clubs is normally stored in a golf bag carried by the player or his caddy, the bag being provided with a pocket to store a supply of golf balls.
Golf balls are usually packed in a box containing a set of three or more balls. Each time a player wishes to obtain a ball, he must open the box to remove a ball therefrom and then close the box. And if the player wishes to load his golf bag with golf balls, he must first remove the balls from the box and insert them in the pocket of the bag.
If the golf bag is heavily used, its golf ball pocket may become dirty, and the balls stored therein may become soiled. Also, when the balls are so stored, they are not adequately protected, and their surfaces may become abraded or scratched.
A golf player who is serious about his game requires golf balls in pristine condition. He also requires a quick access to the balls. These requirements are not met by existing golf ball boxes or packages. | {
"pile_set_name": "USPTO Backgrounds"
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In data center and other environments, a large number of computing peripherals are usually organized in such a way as to efficiently use the physical space available for them. For instance, many such peripherals are rack-mounted. Rack-mounted peripherals have a standard width that enables them to be inserted into industry-standard racks. Racks may themselves be seven feet or more in height, allowing a large number of rack-mounted peripherals to be inserted into a single rack.
A hard disk enclosure blade is a rack-mounted peripheral that accepts a number of trays of hard disk drives. Therefore, in a relatively small space, a large number of hard disk drives can be stored. For instance, one type of hard disk enclosure blade accepts eight trays. Each tray can hold three hard disk drives, such that the hard disk enclosure itself can store a total of twenty-four hard disk drives.
Such a hard disk enclosure blade that is fully populated with twenty-four hard disk drives can be relatively heavy, however. For instance, a fully populated hard disk enclosure blade can weigh more than twenty kilograms, or more than forty-four pounds. Administrators who are responsible for managing such rack-mounted peripherals may not realize that such hard disk enclosure blades are so heavy. Therefore, they may try to remove a fully populated hard disk enclosure blade from a rack, not realizing the full weight of the fully populated blade.
As a result, there is a real potential for the blade accidentally dropping to the floor. While dropping any type of rack-mounted peripheral can potentially cause damage to the peripheral, the chance for damage is heightened with hard disk enclosure blades, because hard disk drives are sensitive to extreme force impacts, which can occur on their being dropped and hitting the floor. For this and other reasons, therefore, there is a need for the present invention. | {
"pile_set_name": "USPTO Backgrounds"
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In the related art, a self-registration system is known as a system that can simplify a purchase transaction. In the self-registration system, a customer launches a self-registration program on a hand-held computing device and registers data of commodities to be purchased through the computing device. As the data registered are transmitted to a point-of-sale (POS) terminal, a process required to complete the transaction at the POS terminal can be simplified.
In the related art, an electronic receipt system is also known as a system that can digitalize contents of a purchase transaction. In the electronic receipt system, a customer launches an electronic receipt program on a computing device and sends a request for electronic receipts related to purchase transactions made by the customer.
Usually, for each of the above computer-based commerce systems, a customer needs a customer (user) ID to log into the system and an authentication process of the system is separately established. It would be desirable if a plurality of computer-based commerce systems can be used in a single purchase transaction in a more convenient manner. | {
"pile_set_name": "USPTO Backgrounds"
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The basic function of a communication system is to send information from a source that generates the information to one or more destinations. In a radio communication system, a number of obstacles must be overcome to successfully transmit and receive information including channel distortion which may cause, for example, intersymbol interference (ISI) and additive noise. The receiver must compensate for the effects of channel distortion and the resulting intersymbol interference. This is usually accomplished by means of an equalizer/detector at the receiver.
A number of different equalization schemes have been used in the past to eliminate or minimize intersymbol interference. The most commonly used approaches include decision feedback equalization (DFE) and maximum likelihood sequence estimation (MLSE). In a maximum likelihood sequence estimation equalization scheme, a detector produces the most probable symbol sequence for the given received sample sequence . An algorithm for implementing maximum likelihood sequence detection is the Viterbi algorithm, which was originally devised for decoding convolutional codes. The application of the Viterbi algorithm to the problem of sequence detection in the presence of ISI is described by Gottfried Ungerboeck in "Adaptive Maximum Likelihood Receiver for Carrier Modulated Data Transmission Systems," IEEE Transactions on Communications, Volume COM-22, #5, May 1974. This MLSE approach employs a matched filter followed by a MLSE algorithm and an auxiliary channel estimation scheme.
A major drawback of using maximum likelihood sequence detection for communications channels which may experience intersymbol interference is that the computational complexity grows exponentially as a function of the span of the intersymbol interference and the number of interfering users. Consequently, maximum likelihood sequence detection is practical only for single user signals where the intersymbol interference spans only a few symbols. Therefore, there is great interest in finding new approaches to sequence estimation which reduce the computational complexity associated with maximum likelihood sequence detection. | {
"pile_set_name": "USPTO Backgrounds"
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Light-emitting diodes (LED) are becoming increasingly used over other types of lights because of advantages in heat and power dissipation, as well as operational life. For example, LEDs are being used in various aerospace applications, including interior instrumentation lights of aircraft for providing flight control information to pilots, and exterior aircraft warning lights (e.g., anti-collision lights) for alerting others as to the aircraft's position and location.
In such flight-critical applications, the degradation or failure of LEDs that occurs over time is a concern. Without adequate monitoring of the operational health of such LEDs, the potential exists for unpredicted malfunctions. Such malfunctions may include overall failure (e.g., a short circuit or open circuit condition), or illumination at a level which is substantially below that dictated by flight regulations.
However, existing LED-based lights are mainly dependent on passive, open-loop control systems. Such control systems do not regulate the lights based on key factors that affect LED operation, e.g., current and diode junction temperature. Also, these previous lighting systems lack the “intelligence” to monitor the key LED parameters in order to estimate remaining operational life and predict future performance of the installed LEDs. In addition, such systems do not provide a way to test for failure conditions while the LEDs are turned off. | {
"pile_set_name": "USPTO Backgrounds"
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In aircraft and launch vehicle construction, various surfaces, such as the skin of an aircraft, may be attached to structural support members known as stringers or stiffeners. In aircraft fuselage, stringers are attached to the fuselage skin run in the longitudinal direction of the aircraft. They are primarily responsible for transferring the aerodynamic loads acting on the skin onto internal structures including frames. In the wings or horizontal stabilizer of an aircraft, stringers attach to the wing skin and their primary function here also is to transfer the bending loads acting on the wings onto internal structures such as ribs and spars.
Traditional manufacturing of stiffening members on composite parts can be tooling intensive. Given the scale of aircraft wings and fuselages, forming and handling equipment for these parts can be expensive, heavy, and require extensive factory floor space. Use of such equipment can also incur undesirable amounts of time and labor.
Thus there exists a need for improved systems and methods for manufacturing aircraft support structures that reduce the need for labor, extensive tooling, factory space, and material handling equipment. | {
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1. Field of the Invention
This invention relates to an apparatus and method for skin tightening. More specifically, the present invention provides an apparatus and method for introducing thermal and mechanical injury to skin via electrodes carrying an electric current.
2. Description of the Prior Art
Achieving a younger looking skin having tight and well defined contours is commonly desired. Traditional devices tighten the skin by applying radio frequency (RF) energy to the surfaced of the skin. An example of a device used to tighten the skin by applying RF energy to the surface of the skin is disclosed in U.S. Pat. No. 5,755,753 to Knowlton (the '753 patent). The '753 patent discloses a device connected to an RF generator. The device includes a porous membrane which is inflated with an electrolytic solution. Once inflated, the membrane conforms to the surface of the skin. The membrane imparts a cooling effect to the skin. A plurality of electrodes are positioned at various locations in the membrane. The generator is coupled to the electrodes and a source for the electrolytic solution is coupled to the membrane. The electrodes impart radiant energy to the layers of the skin. This energy heats the skin and the underlying collagen tissue. As a result of the application of the energy to the surface of the skin, the collagen transforms its structure and contracts.
However, there exists a need for a skin tightening device which combines the benefits of applying thermal and mechanical injury. | {
"pile_set_name": "USPTO Backgrounds"
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A microprocessor is an electronic device capable of performing the processing and control functions for computing devices such as desktop computers, laptop computers, server computers, cell phones, laser printers, and so on. Typically, a microprocessor comprises a small plastic or ceramic package that contains and protects a small piece of semiconductor material that includes a complex integrated circuit. Leads connected to the integrated circuit are attached to pins that protrude from the package allowing the integrated circuit to be connected to other electronic devices and circuits. Microprocessors are usually plugged into or otherwise attached to a circuit board containing other electronic devices.
While a microprocessor integrated circuit typically includes only one computing unit, i.e., one processor, it is possible to include multiple processors in a microprocessor integrated circuit. The multiple processors, which are often referred to as “cores,” are included in the same piece of semiconductor material and connected to the microprocessor package pins. Having multiple cores increases the computing capability of the microprocessor. For example, a microprocessor with four cores can provide almost the same amount of computing capability as four single core microprocessors.
There has been an increase in the use of multiple microprocessors and multiple-core microprocessors in traditional computing devices. Traditional computing devices are capable of running only one instance of an operating system. Even traditional computing devices that contain multiple core microprocessors, multiple microprocessors, or multiple multiple core microprocessors are only capable of running one instance of an operating system. Still, harnessing the increased computing capability that multiple core microprocessors provide allows computing functions, that were previously executed by multiple computing devices, to be executed with fewer computing devices.
For example, a server is a computing device connected to a network that provides a service or set of services to other entities connected to the network. A server comprising 32 traditional computing devices, i.e., a 32 way server, may be comprised of eight microprocessors, each having four cores. Taking the concept one step further, if each individual core is eight times more capable than one of the 32 computing devices, the 32-way server's capabilities can be provided by the four core microprocessor. A clear advantage of such a four core server is that computing resource redundancy is more affordable than that provided by traditional servers. In addition, reducing the number of microprocessors reduces the cost of the server, the amount of energy required to power the server, and the amount of maintenance the server requires.
It is possible to use “partitions” to take greater advantage of the computing capabilities of multiple core microprocessors A partition is an electrically isolatable set of electronic devices, e.g., processors, memory, etc., within a computing device that can run an independent instance of an operating system, i.e., a local operating system. A partitionable computing device is a computing device that can be divided into partitions and thus is able to run multiple local operating systems. A partitionable server is a server that is a partitionable computing device and thus able to run multiple local operating systems. A partition of a partitionable server may also be referred to as a “logical server.” That is, to other entities on a network a logical server appears to be a stand-alone server, even though it is not. It also possible to assemble a plurality of servers, logical or otherwise, into a “server cluster.” A server cluster is a plurality of servers that behave as a unit to provide a service or set of services.
The advantages of using multiple core microprocessors is driving a trend toward “server consolidation.” Server consolidation is the process of replacing multiple servers, for example in a server cluster, with fewer servers, e.g., one server. A server that replaces multiple servers typically contains computing capability that equals or exceeds the capabilities of the multiple servers. While reducing costs, energy, and maintenance, server consolidation has the effect of putting all of one's eggs into one basket. Server consolidation may increase the impact of a server failure. For example, if multiple applications, which used to run on multiple servers, are all run on the same server, and that server fails, the impact is likely to affect all of the applications. In the worst case, this means application downtime. To guard against such an impact, many high end servers, i.e., servers with a large amount of computing capability, apply a portion of their capabilities to reliability features.
One such reliability feature is “failover” capability. Failover is the ability of a first entity to pass the information the first entity contains onto a second similar entity preferably before the first entity completely fails. Techniques have been developed for traditional servers, i.e., servers based on traditional computing devices, to perform failover in a controlled and orderly fashion to ensure that no data is lost and no ongoing processes are interrupted during the transition from the failing server to the replacement server.
In order to create multiple core microprocessor servers that are as robust and reliable as traditional servers, similar techniques that operate at the processor level are useful. Preferably, these techniques are able to run on a plurality of “platforms.” A platform is a combination of hardware, firmware, and software that provides a framework on which higher level software operates and into which other hardware, firmware, and software may be added. | {
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1. Field of the Invention
The present invention relates to the field of portable power cutting tools and to an apparatus which facilitates the ease and safety of handling the portable power cutting tool during the operation of the tool.
2. Description of the Prior Art
Portable power circular saws, jig saws, and other power cutting tools are widely used. Most conventional circular saws come with a flat plate attached to the bottom of the circular saw. When the circular saw is in use to cut a workpiece, the bottom plate of the circular saw comes in contact with the workpiece and slides on the workpiece as the circular saw is moving forward along the cutting direction.
The problem with the conventional flat plate device is that during the cutting operation, extra effort is required from the user of the circular saw to overcome the friction between the bottom plate attached to the circular saw and the work-piece. In addition, the standard attachment plates are heavy and have a tendency to slide in a side-to-side motion which often reduces the accuracy of the cut.
In addition, rotatory power cutting tools such as a rotary power saw can create a dangerous situation called kick-back. The heavy weight of the saw causes the saw blade to move out of the linear motion due to an unstable frictional binding of the flat attachment plate against the workpiece. As a result of this veering of the blade off a straight line motion, the blade may bind with the workpiece and subsequently kick back against the worker, thereby possibly causing serious injury to the worker.
The problem has been address by the present inventor in his U.S. Pat. No. 6,568,088 issued on May 27, 2003 for “Wheel Attachment For Portable Power Cutting Tools”. While that was a fine invention, it was learned by the present inventor that the invention as embodied in the previous patent has several drawbacks. First, the wheel attachment devices must be individually placed on the saw bracket which is time consuming and results in extra effort. In addition, the wheels are not replaceable and if one wheel is broken or is worn, it may affect the operation of the rotary power saw.
The present inventor created certain improvements in the device as disclosed and claimed in U.S. Pat. No. 6,568,088, which improvements are described and claimed in co-pending patent application Ser. No. 11/413,994 filed on Apr. 28, 2006. The present inventor has now made additional significant improvements to the device as disclosed and claimed in patent application Ser. No. 11/413,994 which substantially increases the ease of operation of the tool and provide significant advantages in the operation of the tool.
The following twenty-seven (27) patents and published patent applications are also relevant to the field of the present invention:
1. U.S. Pat. No. 1,753,959 issued to Alfred Wikstrom on Apr. 8, 1930 for “Guide Wheel For Woodworking Tools” (hereafter the “Wikstrom Patent”);
2. U.S. Pat. No. 1,808,228 issued to Eugene Hulack et al. on Jun. 2, 1931 for “Attachment For Electric Drills” (hereafter the “Hulack Patent”);
3. U.S. Pat. No. 2,676,624 issued to Arthur C. Gecmen on Apr. 27, 1954 for “Guide Carriage For Power-Driven Hand Tools” (hereafter the “Gecmen Patent”);
4. U.S. Pat. No. 2,728,141 issued to Martin Green on Dec. 27, 1955 for “Foot Plate Or Base For Cloth Cutting Machine” (hereafter the “Green Patent”);
5. U.S. Pat. No. 2,800,933 issued to Don L. Michael on Jul. 30, 1957 for “Rip Guide For Portable Electric Saws” (hereafter the “Michael Patent”);
6. U.S. Pat. No. 2,839,098 issued to Whitfield Moretti et al. on Jun. 17, 1958 for “Cut-Line Indicator For Portable Circular Saw” (hereafter the “Moretti Patent”);
7. U.S. Pat. No. 3,097,430 issued to Julius Lewinski et al. on Jul. 16, 1963 for “Cutter” (hereafter the “Lewinski Patent”);
8. U.S. Pat. No. 3,344,824 issued to Anthony Greco on Oct. 3, 1967 for “Guide Device For Portable Electric Saws” (hereafter the “Greco Patent”);
9. U.S. Pat. No. 3,839,789 issued to John E. Valkosky on Oct. 8, 1974 for “Easy Rolling Circular Saw” (hereafter the “Valkosky Patent”);
10. U.S. Pat. No. 4,087,914 issued to Arthur Edward Bates on May 9, 1978 for “Guide Assembly For Portable Saws” (hereafter the “Bates Patent”);
11. U.S. Pat. No. 4,275,501 issued to Darrell w. Haire and assigned to Michael Herr et al. on Jun. 30, 1981 for “Laminate Cutting Assembly” (hereafter the “Haire Patent”);
12. U.S. Pat. No. 4,414,745 issued to Gerhard Kuhlman et al. and assigned to Robert Bosch GmbH on Nov. 15, 1983 for “Guiding Arrangement For A Hand Tool” (hereafter the “Kuhlman Patent”);
13. U.S. Pat. No. 4,619,170 issued to Peter Maier et al. on Oct. 28, 1986 for “Guide For A Hand Power Tool” (hereafter the “Maier Patent”);
14. U.S. Pat. No. 4,928,662 issued to Edward Chiuminatta et al. on May 29, 1990 for “Skid Plate For Cutting Unhardened Concrete” (hereafter the “Chiuminatta Patent”);
15. U.S. Pat. No. 5,433,008 issued to David L. Barger, Jr. et al. and assigned to Porter-Cable Corporation on Jul. 18, 1995 for “Circular Saw With Variable Adjustment Stops” (hereafter the “Barger Patent”);
16. U.S. Pat. No. 5,815,931 issued to Todd Cleveland and assigned to Robert E. Cummings on Oct. 6, 1998 for “Cutting Guide For Controlling The Direction And Cut Of A Hand Held Power Cutting Tool” (hereafter the “Cleveland Patent”);
17. U.S. Pat. No. 5,901,450 issued to Thomas Paul James and assigned to Milwaukee Electric Tool Corporation on May 11, 1999 for “Rip Guide For A Circular Saw” (hereafter the “James Patent”);
18. U.S. Pat. No. 6,202,311 issued to Richard C. Nickels, Jr. and assigned to Black & Decker Inc. on Mar. 20, 2001 for “Circular Saw With Bevel Angle Adjustment Mechanism” (hereafter the “Nickels Patent”);
19. U.S. Pat. No. 6,397,716 issued to Andrea Garuglieri and assigned to Black & Decker Inc. on Jun. 4, 2002 for “Bevel Saw Angle Indicator” (hereafter the “Garuglieri Patent”);
20. U.S. Published Patent Application No. 2002/0066190 issued to Michael Fey et al. on Jun. 6, 2002 for “Guide Means For A Circular Saw” (hereafter the “Fey Published Patent Application”):
21. U.S. Published Patent Application No. 2003/0070306 issued to Jon Anthony McDonald on Apr. 17, 2003 for “Apparatus For Supporting A Cutting Saw About A Substrate” (hereafter the “McDonald Published Patent Application”);
22. U.S. Pat. No. 6,568,088 issued to Mathias Am Ende on May 27, 2003 for “Wheel Attachment For Portable Power Cutting Tools” (hereafter the “Ende Patent”);
U.S. Pat. No. 6,757,981 issued to Philip W. Hampton on July 6, 2004 for “Universal Rip Guide For Circular Saw” (hereafter the “Hampton Patent”);
24. U.S. Published Patent Application No 2005/0000338 issued to Joseph Wascow on Jan. 6, 2005 for “Circular Saw Having Bevel And Depth Of Cut Detent System” (hereafter the “Wascow Published Patent Application”);
25. U.S. Pat. No. 7,159,323 issued to Alex Petrenko on Jan. 9, 2007 for “Circular Saw For Facilitating Straight Cuts And/Or Cuts At A Desired Angle Relative To A Workpiece Edge” (hereafter the “Petrenko Patent”);
26. U.S. Pat. No. 7,714,641 issued to Masaki Kondo et al. and assigned to Maktia Corporation on Feb. 13, 2007 for “Cutting Tool” (hereafter the “Kondo Patent”);
27. Patent Abstract of Japan No. 2002370202 issued to Kakimoto Kazuhiro on Dec. 24, 2002 for “Circular Saw” (hereafter the “Kazuhiro Patent Abstract of Japan”).
The Wikstrom Patent discloses the concept of having a guide wheel 16 which moves ahead of the saw to assist the saw blade 18 in cutting a straight line.
The Hulack Patent discloses an attachment for electric drills including a plurality of rollers 5 which are adapted to have rolling contact with the work piece. It also shows the ability to adjust the angle of the work piece by rotatable member 35 having a channel 38.
The Gecmen Patent discloses a guide for a power driven hand tool. It discloses the concept of having the frame member C which causes the saw to move in a straight line as the guide goes against the side of the work piece as best illustrated in FIG. 1.
The Green Patent is a foot plate or base for a cloth cutting machine. It discloses the concept of having the rolling wheel assembly as best illustrated in FIG. 1. Specifically, the patent states: “The material supporting rollers also include a central rearward material supporting roller 39, which is mounted in connection with the rear or heel end portion of the foot plate or base 10 behind the central rearward traction roller 31. In addition to said central rearward material supporting roller 39, it is preferred to also provide idler material supporting rollers 40, which are aligned with said central rearward material supporting roller 39 respectively adjacent opposite ends of the latter. A shaft 41, common to said rearward material supporting rollers 39 and 40, serves to rotatably support said rollers in such disposition that the top peripheries thereof project through an opening 14 of the foot plate or base 10, whereby to intersect the top surface of the latter, thus being operative to engage and support the material moving over said top surface during operation of the cutting machine.”
While this patent discloses the concept of the rollers, it is placed in a different way and in a different orientation from the present invention.
The Michael Patent is a rip guide for portable electric saw and discloses the concept of having the transverse member 18 attached with a saw frame so that its vertically orientated portion 38 can be placed against the work piece to assist in guiding the saws to cut in a straight line.
The Moretti Patent discloses a guide member for guiding the straight cut of a saw. Slide 22 is provided with a rip guide being 32 mounted thereon for automatic shifting adjustment as the angle of a blade 5 is changed. Specifically, “The beam 32 is fitted in a longitudinal channel indicated at 33 and cut in the underside of the slide 22. On its upper surface the beam is suitably marked as at 34 (FIG. 2) to indicate the correct measurements from the line indicator edge 27 to a conventional type of rip guide shoe indicated at 35 (FIG. 3). The rip guide shoe as will be readily appreciated in the art is for guiding the saw along the edge of a workpiece in making a cut. The beam 32 is adjustably locked on the slide 22 as by means of a clamping knob 36 in which the upper end of a clamping screw 37 extends from a recess adjacent channel 33. In the recess an eccentric foot 38 of the screw is provided to turn against the edge of the beam and releasably bind the same in the position to which it may be adjusted.”
The Lewinski Patent embodies the concept of having the rolling members contacting the plate to assist in the cutting guide feature. Specifically, “A contact plate 20 extends under the base and has openings 21 therein in which transverse rollers 22 are rotatably mounted on axles 23 secured to the upper surface of the plate in such a manner that the rollers project through the openings in the plate and engage the material being cut. This enables the device to be moved over the material being cut easily and without any tendency for the material to move laterally as an incident thereto.”
The Greco Patent as best illustrated in FIG. 1 once again discloses a cutting guide member with a transverse section 19 and a vertical section 22 for rolling movement to assist the saw in a cutting mode.
The Valkosky Patent discloses an easy rolling circular saw. It does disclose the concept of having rolling members in the front and back of the plate to assist in the guiding of the saw in a horizontal line. However, the overall structure of this invention is different from the present invention.
The Bates Patent is a guide assembly for portable saws. This includes: “A guide for enabling straight-line tracking of handheld portable power saw over a work-piece having a clamp adapted to be secured at the forward edge of the sole plate of the saw, the clamp having at least one roller mounted thereon providing roller support for the saw on the work-piece, the roller having axially spaced apart work-piece engaging sections so as to inhibit angular deviation of the saw as it is moved over the work-piece.”
The Haire Patent discloses a laminate cutting assembly. There are wheels 58 but the wheels are on swivels and therefore in addition can orient to cut the tool in various orientations because of the swivel features of the wheels.
The Kuhlman Patent discloses the concept of having a transverse guide 6 and loop shaped projection 18 which can go against the work piece to assist in guiding the cutting saw.
The Maier Patent is a guide for a hand power tool assembly and discloses a foot plate that has a recess thereon which enables it to completely straddle the guide plate while giving lateral guidance. In the recess, there are spring loaded rollers or shoes pressing on the guide plate. “As will be seen in FIG. 3, the recess 11 is widened out in steps near the bar members 14 so that the guide plate 4 bridges over the recess 11 like a gantry or portal. In the wider part of the recess 11 there are spring loaded wheel members 19 or sliding shoes 20, that run on the topside of the guide plate 7 and give the desired loading pressure. The use of wheel members or sliding shoes means that the foot plate 4 is able to run on the guide plate 7 with little friction.”
Therefore, this invention does disclose the concept of having the spring loaded rollers in the guide plate.
The Chiuminatta Patent is a skid plate for a concrete cutting saw which discloses the concept of rollers to assist in rolling the saw along the concrete. It also discloses: “The pivot block 60 is spaced apart from the base plate 12 by a boss 62 so that the pivot block 60 is above the surface of the base plate 12. On the boss 62 is mounted a selector bracket 64 which comprises a piece of metal roughly resembling a sector gear in shape. The selector bracket 64 has a narrow edge extending in the direction of the extendable handle 58. Into this edge are cut recesses or notches 66. These notches 66 are shaped and located so that the can mate with a tip 68 of a plunger 70 of a solenoid 72. The solenoid 72 is mounted on, and is substantially parallel to, the extendable handle 58.”
Therefore, this patent does disclose the concept of the orienting pivot block.
The Barger Patent discloses a circular saw which includes a means to adjust the orientation of the saw through the variable adjustment stops. Specifically, the patent states: “In the preferred embodiment, the adjustment means includes a base member with an elongated arcuate opening. First and second stops are positioned at opposite ends of the opening. A first stop engagement member is attached to the housing of the saw and is received within the elongated arcuate opening of the base member. A second stop engagement member is selectively mounted on the first engagement member in a first position and a second position. In the first position, the first engagement member engages the first and second stops to define the limits of the planar position of the blade and in its second position, the second engagement member engages the first and second stops to define the limits of the planar positioning of the blade.”
The Cleveland Patent discloses a cutting guide for the purpose of assisting the guiding of the saw as it cuts the workpiece. Specifically, the patent states: “Guide arms 25 and 26 (of FIG. 1) are each formed from an elongated metal rod. Each arm 25 and 26 has a leading end portion 33, a follower portion 35, and an elbow portion 34 located between the leading end and follower portions 33 and 35. The leading end portion 33 of each guide arm 25 and 26 is sufficiently long so that the follower portion 35 can reach an edge of the workpiece. Each elbow portion 34 has a pair of bends to position the follower portion 35 about ½ inch below and in perpendicular alignment with the leading end portion 33. Thus, when the leading end portion 33 of guide arm 25 is inserted through the apertures of guide ears 27 and 29, it may be lockably positioned to allow the follower portion 35 to be selectively distanced from the saw blade 5 so as to be able to engage and ride along a side of the workpiece, thereby controlling the cutting path of the power saw 1 in a direction parallel to the side of the workpiece that is engaged by the follower portion 35 of the guide arm 25.”
The James Patent discloses another configuration for a rip guide for a circular saw. It discloses: “The guide member 108 also includes a second guide surface 124 spaced from and facing opposite to the first guide surface 112. The guide member 108 also includes a second rear surface 128. The second guide surface 124 and the second rear surface 128 define a second guide surface edge 132 therebetween. When the rip guide 10 is supported by the shoe plate 40, the first and second guide surfaces 112 and 124 are generally parallel to the lateral side portions 64 and 68 of the shoe plate 40. Also, when the shoe plate 40 is orientated in the non-beveled, horizontal position perpendicular to the vertical saw blade 22, the first and second guide surfaces 112 and 124 are generally parallel to a vertical plane defined by the saw blade 22. The guide member 108 also includes connecting member 136 between the first guide surface 112 and the second guide surface 124. As best shown in FIG. 3, the guide member 108 is substantially U-shaped. The connecting member 136 is connected at one end to the first guide surface 112 and defines a first smooth, curved or arcuate edge 140 therebetween. At the other end, the connecting member 136 is connected to a second guide surface 124 and defines a second smooth, curved or arcuate edge 144 therebetween.”
The Nickels Patent is a circular saw with bevel angle adjustment member. The bevel angle adjustment mechanism pivotally interconnects the base to the housing such that the circular saw blade is adjustable relative to the base through a range of beveled angles. Therefore, this patent also discloses the concept of orienting the blades at different angles by the mechanism as shown in the front portion of the saw.
The Garuglieri Patent also discloses a beveled angle adjustment mechanism to adjust the angle and cut of the saw blade. It discloses: “A bevel angle indicator for a saw is disclosed. The saw 10 consists of a table 16, a pivot support 26 pivotally mounted with respect to the table 16 about a bevel axis 92 and a mechanical saw blade pivotally mounted with respect to the pivot support 26 about a second axis 28. The pivot support 26 pivots on a pivot block 27 attached to the table 16. A gearing mechanism couples the pivot block 27 and the pivot support 26 to a dial which indicates the angle between the surface of the table 16 and the plane of the saw blade. The gearing mechanism comprises a rack 50 attached to the pivot block 27 and a pinion 54 rotatably journaled in the pivot support 26. Adjustment of the bevel angle of the saw 10 causes the pinion 54 to advance along the rack 50 and therefore rotate relative to the pivot support 26. The pinion 54 is attached to a sleeve 52, the free end of which carries a pointer 56; the pivot support 26 carries a scale 58. The pointer 56 and scale 58 indicate with accuracy the current bevel angle of the saw.”
The Fey Published Patent Application for a guide means for a circular saw was published in 2002. It discloses a pair of wheels on the front and back of the plate to assist the saw in its movement. As set forth in Section 24, the patent states: “The surface region 15 of the one-piece, cylindrical guide roller 12 is in contact with the surface 3 of the workpiece 4, thereby forming a contact region. The contact region extends over the entire length 1 of the guide roller 12. The surface region 15 has an anti-slip coating 16 made of an elastic material, such as rubber. This avoids an uncontrolled sliding of the hand-held power tool on the surface 3. The guide roller 12 extends crosswise to the working direction A over the entire width of baseplate 2.”
The McDonald Published Patent Application again discloses the concept of having the roller assembly to assist a saw and the guide adjustment pivot mechanism 17 to adjust the angle of the saw.
The Hampton Patent is a rip guide for a circular cutting saw. It discloses a guide member which goes against the face 53 which is placed against the face of the workpiece to assist in the straight cutting of the saw.
The Wascow Published Patent Application was published in 2005 and discloses a device to assist in the angle and depth of the saw blade cut. The assembly has a bunch of notches 72 on its outer surface with a mating mechanism enabling it to lock in place through the ratchet teeth 101 as the item is adjusted by the adjusting mechanisms 96 and 99 to enable the angle of the saw to be cut at different angles.
The Petrenko Patent is a guide plate for a circular cutting saw that has a multiplicity of wheels on the bottom and in fact sites your above-discussed patent. It does disclose the concept of having straight line wheels and a multiplicity of wheels in different locations on the guide plate.
The Kondo Patent is a cutting tool which was assigned to Makita Corporation and issued in February 2007. As described in the abstract: “The present invention provides a technique for improving the workability of a cutting tool. According to the present invention, a cutting tool may comprise a body, a base, a sub-base and a parallel ruler. The body may have a blade that can be rotationally driven. The base may be connected to the body, while the base is placed in contact with the upper surface of the workpiece. The body may tilt in a pivotal movement about an axis substantially parallel to the cutting direction such that a cutting operation can be performed with the blade projecting laterally outward from a side of the base. The sub-base may be removably attached to the base on the side from which the blade projects. The parallel ruler may be removably attached to the base on the side on which the sub-base is attached or on the opposite side of the base, together with the sub-base or in the state in which the sub-base is not attached.”
Finally, the Japanese Published Application English abstract reads: “A plurality of guide rollers 12a and 12b are provided to a side edge 8a along a longitudinal direction of the base 8 of the circular saw. Since the guide rollers 12a and 12b guide the floor plate by abutting against the wall when the floor plate and the like are cut with the circular saw, the wall is not stained with the impulse marks.”
Therefore, there is a significant need for an improved device to assist in the safe operation of a rotary cutting tool and which overcomes the deficiencies in the present inventor's previous inventions. | {
"pile_set_name": "USPTO Backgrounds"
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An electronic still camera, which is now well known, uses an electronic photographing element instead of a photographic film. The electric output signal of the element is electronically processed so that image information is magnetically recorded on a recording medium such as a magnetic disk. The photographing element is often made of an image sensor of 1/2 or 2/3 inch in size. The photographed image area (which is hereinafter referred to as image area) of the element is much less than that of the ordinary photographic film. However, the magnetic disk of the electronic still camera has a size of 54 mm.times.60 mm which is larger than that of the image sensor. The size of a magnetic disk means for driving the magnetic disk is yet larger than that of the disk. When an optical finder is provided in the camera, it is necessary to make the ratio of enlargement high enough to provide such an angle of view as to enable natural viewing. In that case, the volume of an optical system increases as a general rule. Since it is necessary that the still camera can be naturally operated, it is often made nearly equal in size and form to a conventional single-lens reflex camera which employs 35 mm film. Since the optical system and the magnetic disk system of the electronic still camera are large in size, the whole circuit is also large in size and the cost of the camera is likely to be high. If the cost of the electronic still camera is higher than that of the conventional single-lens reflex camera employing the photographic film, the user of the electronic still camera demands that the electronic still camera has a higher functionality. Although the electronic still camera has advantages that the image photographed by the camera can be immediately confirmed and the magnetic disk can be repeatedly used, the camera has a major disadvantage that the quality of the image is considerably lower than that of an image photographed on the photographic film. For that reason, the electronic still camera has not become as popular as the conventional single-lens reflex camera employing the photographic film.
Since the quality of the image photographed by the electronic still camera which sends out a standard television signal is lower than that of the image photographed on the photographic film, the range of objects to be photographed by the electronic still camera is limited. Therefore, if an image of high quality is to be obtained, the camera employing the photographic film needs to be used for photographing.
Since the size of the image made on the image sensor of the electronic still camera is usually smaller than that of the image made on the photographic film, the electronic still camera needs a special lens for the size of the image made on the image sensor. For that reason, if the electronic still camera is of the lens exchange type, an exchangeable lens different in type from that of the conventional single-lens reflex camera needs to be prepared for the electronic still camera.
Since the conventional camera employing the photographic film has an optical finder, the photographer cannot observe the photographed image if he is at a distance from the camera. | {
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Flexography is a method of printing that is commonly used for high-volume runs. Flexography is employed for printing on a variety of substrates such as paper, paperboard stock, corrugated board, films, foils and laminates. Newspapers and grocery bags are prominent examples. Coarse surfaces and stretch films can be economically printed only by means of flexography. Flexographic printing plates are relief plates with image elements raised above open areas. Generally, the plate is somewhat soft, and flexible enough to wrap around a printing cylinder, and durable enough to print over a million copies. Such plates offer a number of advantages to the printer, based chiefly on their durability and the ease with which they can be made.
Corrugated board generally includes a corrugating medium which is typically a layer of pleated or multi-grooved paperboard, called “flute”, adjacent to a flat paper or paper-like layer called a “liner.” A typical corrugated board construction comprises a flute layer sandwiched between two liner layers. Other embodiments may include multiple layers of flute and/or liner. The fluted interlayer provides structural rigidity to the corrugated board. Since corrugated board is used as packaging and formed into boxes and containers, the liner layer forming an exterior surface of the corrugated board is frequently printed with identifying information for the package. The exterior liner layer often has slight indentations due to the uneven support of the underlying flute layer.
A problem that may be encountered when printing on corrugated board substrates is the occurrence of a printing effect referred to as “fluting” (and which is also known as “banding” or “striping” or “washboarding”). Fluting may occur, when printing the liner on the exterior surface of the corrugated board, after the corrugated board has been assembled. The fluting effect is visible as regions of dark printing, i.e., bands of higher density, alternating with regions of light printing, i.e., bands of lighter density that correspond to the underlying fluting structure of the corrugated board. The darker printing occurs where uppermost portions of the pleated innerlayer structure support the printing surface of the liner. The fluting effect can be apparent in areas of a printed image having tones or tint values where the inked areas represent a fraction of the total area as well as in areas of the printed image where the ink coverage is more complete. This fluting effect is typically more pronounced when printing with a flexographic printing element produced using a digital workflow process. Furthermore, increasing the printing pressure does not eliminate striping, and the increased pressure can cause damage to the corrugated board substrate. Therefore, other methods are needed to reduce striping or fluting when printing on corrugated board substrates.
A typical flexographic printing plate as delivered by its manufacturer is a multilayered article made of, in order, a backing, or support layer; one or more unexposed photocurable layers; a protective layer or slip film; and often a protective cover sheet.
The support sheet or backing layer lends support to the plate. The support sheet, or backing layer, can be formed from a transparent or opaque material such as paper, cellulose film, plastic, or metal. Preferred materials include sheets made from synthetic polymeric materials such as polyesters, polystyrene, polyolefins, polyamides, and the like. Generally the most widely used support layer is a flexible film of polyethylene teraphthalate. The support sheet can optionally comprise an adhesive layer for more secure attachment to the photocurable layer(s). Optionally, an antihalation layer may also be provided between the support layer and the one or more photocurable layers. The antihalation layer is used to minimize halation caused by the scattering of UV light within the non-image areas of the photocurable resin layer.
The photocurable layer(s) can include any of the known photopolymers, monomers, initiators, reactive or non-reactive diluents, fillers, and dyes. The term “photocurable” refers to a composition which undergoes polymerization, cross-linking, or any other curing or hardening reaction in response to actinic radiation with the result that the unexposed portions of the material can be selectively separated and removed from the exposed (cured) portions to form a three-dimensional or relief pattern of cured material. Preferred photocurable materials include an elastomeric compound, an ethylenically unsaturated compound having at least one terminal ethylene group, and a photoinitiator. Exemplary photocurable materials are disclosed in European Patent Application Nos. 0 456 336 A2 and 0 640 878 A1 to Goss, et al., British Patent No. 1,366,769, U.S. Pat. No. 5,223,375 to Berrier, et al., U.S. Pat. No. 3,867,153 to MacLahan, U.S. Pat. No. 4,264,705 to Allen, U.S. Pat. Nos. 4,323,636, 4,323,637, 4,369,246, and 4,423,135 all to Chen, et al., U.S. Pat. No. 3,265,765 to Holden, et al., U.S. Pat. No. 4,320,188 to Heinz, et al., U.S. Pat. No. 4,427,759 to Gruetzmacher, et al., U.S. Pat. No. 4,622,088 to Min, and U.S. Pat. No. 5,135,827 to Bohm, et al., the subject matter of each of which is herein incorporated by reference in its entirety. More than one photocurable layer may be used.
The photocurable materials generally cross-link (cure) and harden through radical polymerization in at least some actinic wavelength region. As used herein, actinic radiation is radiation capable of effecting a chemical change in an exposed moiety. Actinic radiation includes, for example, amplified (e.g., laser) and non-amplified light, particularly in the UV and violet wavelength regions. One commonly used source of actinic radiation is a mercury arc lamp, although other sources are generally known to those skilled in the art.
The slip film is a thin layer, which protects the photopolymer from dust and increases its ease of handling. In a conventional (“analog”) plate making process, the slip film is transparent to UV light. In this process, the printer peels the cover sheet off the printing plate blank, and places a negative on top of the slip film layer. The plate and negative are then subjected to flood-exposure by UV light through the negative. The areas exposed to the light cure, or harden, and the unexposed areas are removed (developed) to create the relief image on the printing plate. Instead of a slip film, a matte layer may also be used to improve the ease of plate handling. The matte layer typically comprises fine particles (silica or similar) suspended in an aqueous binder solution. The matte layer is coated onto the photopolymer layer and then allowed to air dry. A negative is then placed on the matte layer for subsequent UV-flood exposure of the photocurable layer.
In a “digital” or “direct to plate” plate making process, a laser is guided by an image stored in an electronic data file, and is used to create an in situ negative in a digital (i.e., laser ablatable) masking layer, which is generally a slip film which has been modified to include a radiation opaque material. Portions of the laser ablatable layer are ablated by exposing the masking layer to laser radiation at a selected wavelength and power of the laser. Examples of laser ablatable layers are disclosed for example, in U.S. Pat. No. 5,925,500 to Yang, et al., and U.S. Pat. Nos. 5,262,275 and 6,238,837 to Fan, the subject matter of each of which is herein incorporated by reference in its entirety.
After imaging, the photosensitive printing element is developed to remove the unpolymerized portions of the layer of photocurable material and reveal the crosslinked relief image in the cured photosensitive printing element. Typical methods of development include washing with various solvents or water, often with a brush. Other possibilities for development include the use of an air knife or heat plus a blotter. The resulting surface has a relief pattern that reproduces the image to be printed. The relief pattern typically comprises a plurality of dots, and the shape of the dots and the depth of the relief, among other factors, affect the quality of the printed image. After the relief image is developed, the relief image printing element may be mounted on a press and printing commenced.
Photocurable resin compositions typically cure through radical polymerization, upon exposure to actinic radiation. However, the curing reaction can be inhibited by molecular oxygen, which is typically dissolved in the resin compositions, because the oxygen functions as a radical scavenger. It is therefore desirable for the dissolved oxygen to be removed from the resin composition before image-wise exposure so that the photocurable resin composition can be more rapidly and uniformly cured.
The removal of dissolved oxygen can be accomplished, for example, by placing the photosensitive resin plate in an atmosphere of inert gas, such as carbon dioxide gas or nitrogen gas, overnight before exposure in order to displace the dissolved oxygen. A noted drawback to this method is that it is inconvenient and cumbersome and requires a large space for the apparatus.
Another approach that has been used involves subjecting the plates to a preliminary exposure (i.e., “bump exposure”) of actinic radiation. During bump exposure, a low intensity “pre-exposure” dose of actinic radiation is used to sensitize the resin before the plate is subjected to the higher intensity main exposure dose of actinic radiation. The bump exposure is applied to the entire plate area and is a short, low dose exposure of the plate that reduces the concentration of oxygen, which inhibits photopolymerization of the plate (or other printing element) and aids in preserving fine features (i.e., highlight dots, fine lines, isolated dots, etc.) on the finished plate. However, the pre-sensitization step can also cause shadow tones to fill in, thereby reducing the tonal range of the halftones in the image.
The bump exposure also requires specific conditions that are limited to only quench the dissolved oxygen, such as exposing time, irradiated light intensity and the like. In addition, if the photosensitive resin layer has a thickness of more than 0.1 min, the weak light of the low intensity bump exposure dose does not sufficiently reach certain portions of the photosensitive resin layer (i.e., the side of the photosensitive layer that is closest to the substrate layer and furthest from the source of actinic radiation), at which the removal of the dissolved oxygen is insufficient. In the subsequent main exposure, these portions will not cure sufficiently due to the remaining oxygen. Other efforts have involved special plate formulations alone or in combination with the bump exposure.
For example, U.S. Pat. No. 5,330,882 to Kawaguchi, the subject matter of which is herein incorporated by reference in its entirety, suggests the use of a separate dye that is added to the resin to absorb actinic radiation at wavelengths at least 100 nm removed from the wavelengths absorbed by the main photoinitiator. This allows separate optimization of the initiator amounts for the bump and main initiators. Unfortunately, these dyes are weak initiators and require protracted bump exposure times. In addition, these dyes sensitize the resin to regular room light, so inconvenient yellow safety light is required in the work environment. Lastly, the approach described by Kawaguchi employs conventional broadband-type sources of actinic radiation light for bump exposure, and thereby also tends to leave significant amounts of oxygen in the lower layers of the resin.
U.S. Pat. No. 4,540,649 to Sakurai, incorporated herein by reference in its entirety, describes a photopolymerizable composition that contains at least one water soluble polymer, a photopolymerization initiator and a condensation reaction product of N-methylol acrylamide, N-methylol methacrylamide, N-alkyloxymethyl acrylamide or N-alkyloxymethyl methacrylamide and a melamine derivative. According to the inventors, the composition eliminates the need for pre-exposure conditioning and produces a chemically and thermally stable plate.
Other efforts have focused on adding an oxygen scavenger to the resin composition to suppress the action of the oxygen. The use of oxygen scavengers in resin systems is described, for example, in U.S. Pat. No. 3,479,185 to Chambers, Jr. and in U.S. Pat. No. 4,414,312 to Goff et al., the subject matter of each or which is herein incorporated by reference in its entirety.
However all of these methods are still deficient in producing a relief image printing element that produces a superior dot structure, especially when designed for printing corrugated board substrates.
Thus, there is a need for an improved process for preparing relief image printing elements with an improved relief structure similar to or better than the relief structure of a typical analog workflow process for printing on corrugated board substrates. | {
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Magnetic discs with magnetizable media are used for data storage in most computer systems. Current magnetic hard disc drives operate with the read-write heads only a few nanometers above the disc surface and at rather high speeds, typically a few meters per second.
Generally, the discs are mounted on a spindle that is turned by a spindle motor to pass the surfaces of the discs under the read/write heads. Spindle motors generally include a shaft, a base plate, a sleeve, and a hub. The shaft may be separate from and attached to the hub or incorporated in the hub. The shaft and the sleeve rotate relative to each other. Either the shaft rotates and the sleeve remains stationary, or vice versa. Permanent magnets attached to the hub interact with a stator winding on the base plate to rotate the shaft or the sleeve. To facilitate relative rotation of the shaft and the sleeve, one or more bearings are usually disposed between the shaft and the sleeve.
FIG. 1 shows a schematic of a magnetic disc drive with a spindle motor that commonly utilizes a fluid dynamic bearing. Fluid bearings use a thin layer of liquid or gas fluid between the bearing faces. Referring to FIG. 1, a disc drive typically includes a housing having a base sealed to a cover with a seal. The disc drive has a spindle to which are attached one or more discs having surfaces covered with a magnetic media (not shown) for magnetically storing information. A spindle motor (not shown in this figure) rotates the discs past read/write heads, which are suspended above surfaces of the discs by a suspension arm assembly. In operation, the spindle motor rotates the discs at high speed past the read/write heads while the suspension arm assembly moves and positions the read/write heads over one of a several radially spaced tracks (not shown). This allows the read/write heads to read and write magnetically encoded information to the magnetic media from and to the surfaces of the discs at selected locations.
As illustrated in the spindle motor embodiment of FIG. 2, spindle motors can include a shaft having an outer surface that abuts a sleeve. The shaft rotates relative to the sleeve or vice versa. In this embodiment, the shaft is separate from the hub; however, the hub and shaft may have a one-piece construction.
Fluid dynamic bearings are commonly located between the hub/shaft (which refers to a one-piece hub-shaft embodiment and an embodiment with separate hub and shaft) and the sleeve of the motor, which typically move relative to each other. The fluid used in the bearing is commonly an oil, and fluid type choices are usually based on the fluid's viscosity, as well as its equilibrium vapor pressure and the coefficient of gas phase diffusion. The fluid is also referred to herein as lubricant. Fluid dynamic bearing designs are known to use a capillary seal to contain a volume of lubricant necessary for continuous and proper motor operation. FIG. 3 illustrates a vertical cross section of a prior art spindle motor having a fluid dynamic bearing with a capillary seal. This spindle motor embodiment includes a one-piece hub and shaft. Typical bearings lubricants are optimized to have lower viscosity, which decreases motor power consumption and enhances motor performance. In addition, the lubricant preferably has a low equilibrium vapor pressure to reduce fluid loss by evaporation. However, lower viscosity lubricating fluids typically have higher vapor pressure that results in a substantial amount of lubricant being lost from the capillary seal by evaporation and oil vapor diffusion in the gas phase over the life of the motor.
To compensate for lubricant loss, capillary seal are often designed to hold a larger amount of lubricating fluid. The available reservoir volume is, however, limited by motor size constraints and requirements for seal splash robustness during shock events. It is advantageous to minimize the amount of fluid that evaporates from the capillary seal over the life of the motor. This is preferably done without negatively affecting spindle motor performance afforded by low viscosity fluids. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention concerns an aluminum alloy material having a surface of excellent zinc phosphate processability and it relates to a surface treated aluminum alloy material suitable to such an application use that coating is applied after pretreatment with zinc phosphate processing, in particular, to automobile panel materials.
2. Description of the Prior Art
Aluminum alloys have been employed in recent years to automobile parts with an aim of reducing weight and a pretreatment for coating such as with chronic chromate has been necessary in such an application use requiring filmform corrosion resistance such as in panel materials.
Although zinc phosphate processing has been employed for the pretreatment in usual automobile coating lines, no sufficient effect can yet be obtained at present as the pretreatment for aluminum alloys in view of the filmform corrosion resistance.
As the aluminum alloy materials for automobile panels, Al--Mg--Cu type alloys have been used predominantly, because the aluminum alloys of this type tend to readily cause deposition of zinc phosphate and are excellent in the filmform corrosion resistance as compared with Al--Si--Mg type alloys.
Although the Al--Si--Mg type alloys have high strength after baking of the coating and have excellent properties as the automobile panel material, since they cause less deposition of zinc phosphate and can not provide sufficient filmform corrosion resistance as described above, they have been scarcely used at present for the application use of automobile panels using the zinc phosphate processing as the pretreatment.
On the other hand, an attempt of improving the zinc phosphate processability by applying Zn plating to the surface of an aluminum alloy plate has already been conducted, for example, in Japanese Patent Laid-Open Sho 61-157693. Such a technique has an aim of improving the zinc phosphate processability and preventing dissolution of aluminum ions into a zinc phosphate bath by means of a Zn plating layer. Accordingly, about 1 g/m.sup.2 of amount is required as coating weight of plating and Zn plating has to be applied as far as inner panels not requiring the coating surface finishing property or the filmform corrosion resistance. However, if the processing area or the average amount per unit area is increased, the processing cost is increased which is not desirable industrially. Further, if the Zn layer is left after the zinc phosphate processing, it tends to cause swelling in the coating layer and hence is not preferred.
Further, in the prior art, although the filmform corrosion resistance can be improved, for example, in a case of the chronic chromate treatment, the following steps are necessary, and exclusive processing facilities are required, as well as there is a problem that a processing cost including that for waste water disposition is increased. | {
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The present disclosure relates to a separator for disinfecting raw milk or whey. The separator includes a rotatable drum having a vertical axis of rotation, a disk stack, at least two outlets and an inlet. The present disclosure also relates to a method of operating such a separator.
In many food processing businesses, separators are used for numerous different applications and capacity spectrums. The separators generally have to be adapted to these applications and capacity spectrums with respect to their construction and design. Although they can therefore be used within a predefined work area or process, they react sensitively or often with disturbances to deviations from the defined scope and thus to capacity changes or changes of the composition of the products to be processed.
In the area of the disinfecting separators, milk is clarified from spores and/or germs. Within the past few years, the rated capacity of the used disinfecting separators has continuously increased. Separators of many different capacities of, for example, 500 l/h to 50,000 l/h are currently available on the market. For larger machines, the disk diameter currently reaches up to 500 mm.
For a good disinfecting efficiency, it is important that a sufficiently large liquid flow transports bacteria into a centrifugal field. In order to ensure this, a recirculation of an entraining liquid is known from the state of the art. In this case, the entraining liquid is diverted at a point with sufficient centrifugal force and is then removed by way of a separating disk. As a rule, this entraining liquid, which is recirculated into the inlet of the separator, bacteriologically corresponds approximately to the raw milk and is guided back directly into the inlet of the separator. Relative to the inflow quantity, the returned quantity amounts to approximately 3-5%. The amount of entraining liquid can be controlled and should not have more than twice the amount of germs of the raw milk. In contrast, by way of a solids discharge, the actual concentrate of spores and bacteria is discharged.
Such a method, as suggested above, has been successful. However, it is problematic that, despite the recirculation, particularly in the case of machines of a greater rated capacity, there is the effect that a particularly clear reduction, such as a reduction by half of the inflow capacity to half the rated capacity can impair the result of the disinfection. This effect, which does not occur in the case of smaller machines or occurs only to an extent which is not disturbing, has the result that, although the larger machines can be used well in the range of their rated capacity, they can only be used to a more restricted extent in clearly lower capacity ranges.
In contrast to the above-described state of the art, the present disclosure relates to increasing the clarifying effect of clarifying separators when disinfecting raw milk or whey.
Thus, the present disclosure relates to a separator for disinfecting raw milk or whey. The separator includes a rotatable drum having a vertical axis of rotation. The separator also includes a disk stack, at least two outlets and an inlet. Further included are a first and a second recirculation circuit located between the at least two outlets and the inlet. The present disclosure also relates to a method of operating a separator to disinfect raw milk or whey. The separator includes a rotatable drum having a vertical axis of rotation and further includes a disk stack, at least two outlets, an inlet, and a controlling device located between the at least two outlets and the inlet. The method steps include: providing a product to be processed to the separator; operating the separator; regulating the product quantity processed by controlling an amount of a recirculated product phase into the inlet such that the separator operates independently of variations of an inflow of the product quantity to be processed; and, further operating the separator within a range of an optional clarifying effect by recirculating a portion of a disinfected milk phase with an entraining liquid to the inlet.
As noted above, the present disclosure provides a separator having two recirculation circuits between the two outlets and the inlet of the separator drum.
One of the recirculation circuits is designed for the recirculation of an entraining liquid during the disinfecting of milk. That recirculation circuit has a recirculation pipe extending from the outlet of the centrifuge for entraining liquid to the inlet of the centrifuge. The other recirculation circuit is designed for the recirculation of a portion of the disinfected milk phase during the disinfecting of milk and has another recirculation pipe from the outlet of the centrifuge for disinfected milk to the inlet of the centrifuge. A valve is integrated in the recirculation circuits and pipes, which can be controlled and/or regulated.
According to an embodiment of the present disclosure, a controlling or regulating device is also provided for keeping the product quantity processed by the separator constant by regulating the recirculation circuits.
It is within the scope of the present disclosure to supplement the advantageous recirculation circuit for entraining liquid, which is known, by another recirculation pipe or recirculation circuit for clarified or disinfected milk or whey, by which the clarified milk or whey is guided back into the inlet. The additional recirculation circuit has, for example, the following advantage. When the throughput capacity becomes lower, the disinfecting effect is stabilized or even improved at a high level as a result of the separator and method of the present disclosure. When the capacity is reduced, for example, to half, this could theoretically be even by a “double disinfection”, because the flow through the drum takes twice as long as in the case of the “single disinfection”.
In practice, an improvement of the disinfection according to the known art, can take place only if the construction of the drum, i.e., the parts through which the flow passes, is also adapted to the reduced capacity. That is because the product may otherwise be damaged, the milk may be degassed in the inlet area, and a resulting partial blocking of the milk flow may take place. In order to avoid these problems, it would therefore be necessary to adapt the discharge, the grippers, the distributors, the inlet and outlet area, the concentrate output, etc. of the separator to the changed capacity. All these disadvantages are avoided in a simple manner by the second recirculation pipe.
Thus, by the second recirculation pipe, in the case of a disinfecting separator, the inflow capacity can be reduced. Or, under certain circumstances, in the case of smaller machines, a type of “double disinfection” can be carried out, in which case, for keeping the inflow volume of whey stable, the second recirculation pipe can be activated. Here, the pipe is selected such that a reduction of the inflow quantity is compensated by the recirculation. This ensures that the pressure range which was set is not left. The grippers or centripetal pumps always deliver in the optimal range. As a result of the same inflow conditions by the double flowing of the liquid through the drum, a stabile and improved disinfection of below 50 spores per liter is achieved also at low capacities.
In addition, the present disclosure relates to a method of operating a clarifying separator. By a controlling or regulating device, a regulating of the product quantity processed by the separator takes place. This is done by a controlling or regulating of the quantity of recirculated product phase into the inlet of the separator drum such that the separator operates independently of variations of the inflow quantity of milk product under hydraulically constant conditions, that is, the same flow conditions exist in the drum. The separator is operated within the range of an optimal clarifying effect by a recirculation of clarified milk diverted from the separator drum, with an optional return of an entraining liquid.
The following references relate to different methods of processing milk products but do not relate to the solution of the initially mentioned problems occurring during the disinfection by separators.
From German Patent Document DE 100 36 085, it is known to separate the raw whey into the cream, skimmed whey (skimmed milk) and solids (sludge with germs) constituents by a clarifying separator. When disinfecting whey, the centrifugal separation in the separator takes place such that the fat content in the cream amounts to more than 45%. Subsequently, the skimmed milk is disinfected and is then returned into the cream which was subjected to no further disinfection. The cream/skimmed milk mixture created by returning the skimmed milk into the cream is pasteurized. As a result of this method, a high pasteurization of up to 135° C. will not be necessary.
From German Patent Document DE 198 07 294, a skimming station with a clarifying separator and a skimming separator connected on the output side of the clarifying separator is known. A recirculation pipe for skimmed milk leads from the outlet of the skimming separator to the inlet of the clarifying separator, i.e., a bypass pipe, in order to minimize the loss of fat and to improve the quality of the obtained cheese powder.
German Patent Document DE 198 20 870 suggests that, during the skimming of whey by a separator, a partial quantity of from 0.5% to 2% of the outflowing whey cream, thus of the fraction containing more fat, be returned into the raw whey fed to the separator in order to improve the product quality.
Other aspects of the present disclosure will become apparent from the following descriptions when considered in conjunction with the accompanying drawings. | {
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Commonly employed fabrication techniques for displays and polymer based devices or other semiconductor electronic devices involve several imaging steps. A substrate coated with a resist or other sensitive material is exposed to radiation through a photo-tool mask to effect some change. By nature these fabrication processes involve a large number of separate steps, each step commonly having a finite risk of failure, thus reducing the overall process yield and increasing the cost of fabricating the finished article. A specific example is the fabrication of color filters for flat panel displays. Color filter fabrication can be a very expensive process because of the high cost of materials and low process yield. Traditional photolithographic processing involves applying color resist materials to a substrate using various coating techniques such as spin coating, slit and spin and spin-less coating. The material is then exposed via a photo-tool mask followed by a development process.
Direct imaging has been proposed for use in the fabrication of displays and in particular color filters. U.S. Pat. No. 4,965,242 to DeBoer et al. describes a dye transfer process for making a color filter element. A dye receiving element is overlaid with a dye donor element which is then imagewise heated to selectively transfer the dye from the donor to the receiver. The preferred method of imagewise heating is by means of a laser beam. Diode lasers are particularly preferred for their ease of modulation, low cost and small size.
Direct imaging has the potential for replacing a multiplicity of steps associated with traditional photolithographic processes with a single imaging step. A downside of direct imaging is that the laser beam is required to scan over the entire surface of the substrate. This necessitates very fast imagewise scanning of the substrate in order to preserve the advantages of direct imaging over flood exposure. Flood exposure through a photo-tool mask is by nature a very fast imaging process because a small substrate may be exposed at once, or a series of quick step repeat exposures may be used for larger substrates. One way to increase the speed of the direct imaging is to expose the substrate simultaneously with a plurality of laser beams. U.S. Pat. No. 6,146,792 to Blanchet-Fincher et al. describes the production of a durable image on a receiver element, such as a color filter. The laser head suggested in the examples consists of thirty-two 830 nm laser diodes, each having approximately 90 mW of single-mode output.
Imaging heads with even more channels are now commonly available, exemplified by the SQUAREspot® thermal imaging heads manufactured by Creo Inc. of Burnaby, British Columbia, Canada. These imaging heads are available with up to 240 independent imaging channels each channel having upwards of 100 mW of optical output power per channel. Such imaging heads offer imaging of a small 370×470 mm color filter substrate in around 3 minutes for a media sensitivity of 450 mJ/cm2.
Further improvement in imaging speed is often frustrated by the trade-off between imaging resolution and speed. Color element edge definition requirements dictate that a small pixel size be used (i.e. high resolution imaging). However, the smaller the pixel, the longer it takes to scan over the substrate to effect the imagewise exposure. The availability of imaging heads with progressively more channels does not entirely address this problem since the required number of channels are difficult to provide in an economical and practical imaging system.
The speed/resolution trade-off, coupled with the industry trends towards processing larger and larger substrates presents a unique challenge for direct imaging systems. Larger substrates are not only of application in producing larger displays but also in improving the economy and yield of smaller display panel fabrication. A large substrate may be processed and later separated into a number of smaller panels. Having more panels per processed substrate reduces the chance that an entire substrate that has been processed will be un-unusable (2 faults on a 4 panel substrate is a 50% yield while the same 2 faults on a 12 panel substrate is an 83% yield). In the display fabrication industry, so-called “sixth generation” flat panel display substrate sizes are around 1500×1800 mm. For the example above having 450 mJ/cm2 media sensitivity the imaging time with the 240 channel imaging head would be in the region of 45 minutes, which is prohibitively long, particularly when compared to flood exposure, which is only marginally slower for a larger substrate where relatively large areas are imaged in a series of step and repeat exposures.
There remains a need for higher productivity direct imaging techniques used in the fabrication of color filters and other polymer based electronic devices. | {
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Nuclear reactor instrumentation systems include a multitude of sensors for monitoring various nuclear reactor system parameters, e.g., pressure, temperature, liquid level, and neutron flux. The data measured by the sensors in the reactor instrumentation system are generally transmitted to a control room and displayed on meters, gauges, or display screens to nuclear reactor operators. The operators rely on data provided by reactor instrumentation systems to safely operate the nuclear reactor system and to identify and respond to potential emergency situations.
With respect to nuclear reactor systems, issues may arise beyond the design of the nuclear power plant, including external events or accidents such as seismic events, aircraft impacts, a complete loss of power, or accidents directly affecting a control room and not the reactor (e.g., fire in the control room). While these types of accidents may not directly affect a nuclear reactor such as to trigger design basis protection systems, they may affect an operator's ability to monitor the reactor. For example, a fire in a control room, a complete loss of electrical power, or an aircraft impact may be isolated from the reactor but may nonetheless impair the reactor monitoring systems or the control room. Alternatively, such events may also directly affect the reactor or the buildings or locations where the events occur, thereby creating conditions that are hazardous to safe human habitability and which may impede the ability to monitor conditions locally.
The invention as described below is directed to a remote monitoring system which, in some versions, may prevent reactor operators or emergency personnel from having to enter a hazardous environment in order to determine critical reactor parameters necessary to verify proper operation or reactor safety systems (e.g., decay heat removal systems and containment systems) upon the occurrence of such accidents or events. | {
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The invention relates to soft tissue repair and reconstruction. More particularly the invention relates to the fixation of a graft within a bone tunnel.
The repair and reconstruction of torn or damaged soft tissues is a common surgical procedure. For example, replacement graft ligaments may be secured at the site of the original ligament. The procedure generally involves drilling bone tunnels into adjacent bones at the site of the original ligament and securing within these bone tunnels a graft ligament. In many applications, such as in the knee joint, such procedures may be performed arthroscopically. The graft ligament may be an autograft, an allograft, a xenograft, and/or it may be totally artificial and synthetic. The most common types of graft ligaments include, for example, bone-tendon-bone grafts and soft tissue grafts such as semitendinosus and gracilis tendons. Both types are harvested by techniques well known to those skilled in the art. For example, repair of the anterior cruciate ligament (ACL) of the knee is often performed arthroscopically in a procedure which involves drilling a bone tunnel through the proximal tibia and into the distal femur. A variety of different types of graft ligaments may be secured in the bone tunnels in the femur and the tibia to replace the ACL.
Various fixation methods are used to secure the graft ligament within the femur and within the tibia. It is desirable that the fixation method be able to satisfactorily engage the bone in the wall of the bone tunnel or on the cortical bone surface. Consideration must be given to the fact that the bone may have only a thin layer of relatively hard cortical bone, such as in the anterior proximal surface and tibial plateau of the tibia. The bone may be otherwise relatively soft, cancellous bone. Depending upon the patient, the quality of the bone may vary considerably, particularly the cancellous bone. It would, therefore, be desirable to have a device capable of achieving fixation of the graft while eliminating the variability of fixation caused by the varying strength and density of cancellous bone.
Another consideration is that for biological graft fixation, that is, fixation resulting from tissue growing between the bone tunnel wall and the graft, some consideration should be given to facilitating such growth by enabling direct contact between the graft and the surrounding bone. | {
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This invention is in the field of battery chargers and power supplies. In particular, a preferred embodiment of the present invention comprises a programmable power supply and battery charger for a portable computer.
Using an alternating current ("AC") to direct current ("DC") adapter to power a portable computer is known. It is also known to use the adapter to power the computer and simultaneously charge the battery for the portable computer. However, known adapters and charging systems are very limited in the number and type of batteries they can recharge. Although many different types of batteries can be used with any given computer; a separate battery charger is needed for each of these different types, as the charger is preset to charge at a specific rate and for a specific amount of time. Known chargers are also passive devices which cannot vary the charging current or time in response to the battery's actual condition.
Known attempts to integrate the mechanisms of an AC adapter and a battery charger have resulted in units that are somewhat awkward to use. Typically, the battery charger is a separate unit from the AC adapter. This increases the number of devices that a user must own and manipulate and prevents the battery charger from being used conveniently with the adapter.
Given the limitations of known AC adapters and battery chargers, a single AC adapter/battery charger that could recharge several different types of battery packs and that could actively monitor the charging status of the battery pack and modify the charging process to accommodate individual variations in the battery pack would be very desirable. If these qualities could be realized in a compact and physically well-designed package, the device would be even more desirable. | {
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The subject matter of the present invention relates generally to oscilloscope sweep systems, and in particular to a dual time-base sweep system for accurate differential time measurements down to and including zero time, defined herein as the time base triggering event.
Conventional dual time base oscilloscopes have two sweep generators in which the starting point of a so-called delayed, or B, sweep may be selected at any time point along a so-called delaying, or A, sweep to permit expanding selected A sweep segments or making differential time measurements between certain events. It is imperative in oscillography that the time base sweep signal be linear so that the trace-producing spot is driven across the screen of the cathode-ray tube (CRT) at a constant rate of speed. For the most part, modern oscilloscopes have very linear sweeps over a specified region which excludes a short period of time following sweep initiation. The reason for this is, of course, that sweep start up immediately following sweep initiation is non-linear due to the inherent bandwidth and non-linearity of the devices of the sweep system at turn on. This nonlinear sweep startup precludes accurate differential time measurements beginning with the A-sweep triggering event because the nonlinear startup portion is necessarily included in the measurement when the delay reference is set at zero. Moreover, in most cases, the triggering event is not even visible on the delayed sweep because of the inherent delays in the A and B sweeps.
Another problem in prior art oscilloscopes is that the displayed sweep trace is shifted to the right at higher sweep speeds because the unblanking pulse must be delayed to hide the non-linear sweep startup. | {
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Document GB 863 085 describes a lifting device which comprises lifting means directly mounted on structural tubes of a helicopter frame. A supporting structure, immobilization means securing the supporting structure to the frame are also disclosed.
Document U.S. Pat. No. 3,380,688 describes a device for mounting and/or dismounting in particular helicopter engines. The device comprises a support member coupled to the rotor head of the helicopter and a carriage member movable horizontally on said support member. | {
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Conventional vehicle communication systems, in order to send a message to a control unit, are designed to attach, to the message to be sent, an address identifying the control unit.
In addition, in vehicle diagnosis monitoring, an operator communicably connects, to an in-vehicle communication network, a diagnosis monitoring device, such as a diagnosis monitoring tool. Next, the operator operates an enter key and the like of the diagnosis monitoring device to enter, into the diagnosis monitoring device, information indicative of a control unit (target control unit) in which a target function is installed beforehand and of descriptions associated with diagnosis monitoring of the target function. The descriptions are to instruct the target control unit what the operator wants to monitor and diagnose regarding the target function.
In response to the information entry, the diagnosis monitoring device sends, to the target control unit, request messages identifying the target control device as its destination and requesting it to execute diagnosis monitoring of the target function in accordance with the descriptions.
Note that the request messages for diagnosis monitoring include a data request message that requests a target control unit to execute a function of returning control data stored therein and/or a drive request message that requests a target control unit to execute a function of forcibly driving an actuator. The actuator is configured to put in-vehicle devices into automatic action, such as force or motion.
Techniques associated with routers that connect a plurality of different networks to each other are disclosed in European Unexamined Patent Publication No. EP1039725A2 corresponding Japanese Unexamined Patent Publication No. 2000-244549.
In the conventional vehicle diagnosis monitoring set forth above, an operator to manipulate the diagnosis monitoring device, in other words, an operator to perform vehicle diagnosis monitoring needs to previously grasp which functions are installed in advance in which of the control units. This may cause the diagnosis monitoring work to become complicated.
Specifically, hardware standardization among communication systems installed in vehicles is being promoted, which produces an improvement in the portability of applications to realize various types of functions.
For these reasons, even if the functions are the same as each other, they may be installed in different control units depending on the vehicle models. In addition, even if vehicles have the same model, depending on their different grades and/or their different options, they may have different functions installed therein and/or may have different numbers of functions installed therein. | {
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1. Field of the Invention
The present invention relates to a digital multifunction peripheral, which is a computer peripheral unit, and more particularly, to a digital multifunction peripheral that has a fingerprint reader capability using a scan function provided for the digital multifunction peripheral.
2. Description of the Related Art
Japanese Official Gazette, JP-A-2003-123060 discloses an invention that relates to a method and an apparatus for biometrically identifying the user of an MFP (Multifunction Peripheral). The MFP proposed in this invention identifies the user by reading his fingerprint using the scanner function provided for the MFP itself. Before the user uses the MFP, he places his finger on the fingerprint read position provided on the top of the scanner cover of the MFP. Upon judging that the user's finger is placed on the read position with the use of a light or pressure sensor, the MFP reads the user's fingerprint using its own scanner function. The MFP then checks the fingerprint thus read against the fingerprints of the pre-registered authorized users.
In the related art as described above, however, the carriage of the scanner has to be moved to the specified position for reading the fingerprint first, and then the fingerprint is read as the carriage moves. Hence, the user has to keep his finger placed immovably in a reliable manner while the carriage is moving since the user places his finger at the read position until the fingerprint reading ends. The user therefore needs to become aware of the instant at which the fingerprint reading starts and the instant at which the reading is completed. In the related art, however, it is difficult for the user to become aware of the instant at which the fingerprint reading starts because the fingerprint reading starts when it is triggered by the automatic detection of the finger by the sensor. Moreover, in the related art, it takes time from when the sensor detects the finger with the lamp indicating an operating state being lit ON until the carriage reaches the effective image region (that is, in the vicinity of the finger) because the fingerprint is read using the scanner function of the MFP.
This makes it more difficult for the user to become aware of the instant at which the fingerprint reading starts. Under these circumstances, the reading may fail because the user unintentionally moves his finger during the fingerprint reading or before or after the reading starts.
In addition, the read surfaces are not necessarily the same for the case of reading the fingerprint and for the case of reading normal documents. Hence, there is a problem that when the focus of the optical system in the scanner is adjusted to one of the read surfaces, the correct focus is not achieved on the other read surface. | {
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The present invention relates generally to a motor vehicle, and in particular to a system and method for estimating a composition of the fuel mixture in the vehicle.
Vehicles that can operate using mixtures of different fuel types have been previously proposed. Some vehicles are able to operate on mixtures of gasoline and ethanol. Due to the different combustion properties of gasoline and ethanol, the operation of an engine can be varied according to different types of fuel mixtures. It has previously been proposed to use properties associated with the blended fuel to estimate its composition, such as air-fuel ratio meters or gauges that read the voltage output of a lamda or oxygen sensor exposed to exhaust immediately after combustion of the fuel. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to an electric bus bar assembly and, more particularly, to a bus bar assembly that is especially adapted for use as the low voltage bus bar assembly of a polyphase distribution transformer.
In certain polyphase distribution transformers, it is conventional to provide low-voltage electric bus bars extending across the top of the core and coil assembly for electrically interconnecting the coils with each other and with the usual terminal bushings for the transformer. These bus bars must be rigidly supported to maintain them in their desired positions despite high displacement forces, e.g., short-circuit produced magnetic forces, and the support means must be compact to conserve the limited available space. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a disk cartridge capable of recording and reproducing contents of information, a method of manufacturing the same, and to a recording/reproducing system for recording and reproducing the contents of information to and from such a disk cartridge.
2. Description of the Related Art
Recently, it is being realized to record and/or reproduce contents of TV programs to and from a disk cartridge typically represented by a DVD-RAM having therein a large capacity disk such as an optical disk, a magneto-optical disk and the like. | {
"pile_set_name": "USPTO Backgrounds"
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The invention relates generally to distributed, shared-memory multiprocessor systems.
Many multiprocessor systems employ a shared bus to connect multiple processors, memory modules, and I/O devices. Such multiprocessors are usually called symmetric multiprocessors (SMP) since the latency for any processor accessing any portion of memory is uniform. An SMP system usually equips each processor with a cache and provides a snoopy cache coherence protocol to reduce the traffic on the bus. It has been shown that the shared bus is a cost-effective interconnect for attaching more processors owing to simplicity of the SMP architecture. See, for example, W. K. Dawson et al., "A Framework for Computer Design," IEEE Spectrum, pp. 49-54, October 1986; and D. B. Gustavson, "Computer Buses--A Tutorial," IEEE Micro, pp. 7-22, August 1984.
Although the shared bus architecture is simple and effective, the system's performance does not scale well. As the number of processors increases beyond a certain point, the shared bus, due to is limited bandwidth, becomes the major performance bottleneck. Furthermore, given the speed at which processor technology is rapidly progressing, it will be even more difficult in the future for shared bus architectures to provide adequate bandwidth in a multiprocessor system.
Lately, scalable networks have been proposed as an interconnect for multiprocessor systems. Scalable networks, such as rings, meshes, and trees, provide a multiprocessor system with higher bandwidth as the number of processors increases. With scalable networks, a large-scale parallel machine can be built for a number of nodes. Each node can be either a single-processor system or an SMP system.
FIG. 1 shows an example of a scalable multiprocessor system based on the ring network. In general, each node 10 on the ring network 12 includes a CPU 14 with cache memory 16, local memory 18, and a local bus 20, over which CPU 14 can access local memory 18. The node is connected to the ring network 12 through an interface module 22.
For multiprocessors based on scalable networks, it is important to be able to run a wide variety of applications without excessive programming difficulty. A single address space greatly aids in the programmability of multiprocessors by reducing the problems of data partitioning and dynamic load distribution, two of the more difficult problems in programming parallel machines. The shared address space also provides better support for parallelizing compilers, standard operating systems, multiprogramming, and incremental tuning of parallel machines. For further details see D. Lenoski et al., "The DASH Prototype: Logic Overhead and Performance," IEEE Transactions on Parallel and Distributed Systems, pp. 41-61, January 1993.
In multiprocessor systems, it is feasible to physically partition the shared memory into several portions and distribute those portions among the nodes. These shared memory portions can be accessed by all the nodes in the system as described by D. Lenoski et al. in the above-identified reference and as further described by D. Kuck et al., in "Parallel Supercomputing Today and the Cedar Approach," Science, vol. 231, pp. 967-974, February 1986 and by G. Pfister, et al., in "The IBM Research Parallel Processor Prototype (RP3): Introduction and Architecture," International Conference on Parallel Processing, pp. 764-771, August 1985. Such systems are called distributed shared memory multiprocessors. The shared memory will also be called global memory interchangeably in the following. A cache coherence protocol can be included in distributed shared memory multiprocessors in order to improve the performance on shared memory access (see D. Lenoski, above).
Although many distributed shared memory multiprocessor systems can use off-the-shelf microprocessors directly, the interconnect is typically proprietary and cannot connect existing workstations (or personal computers) in a "pay-as-you-go" fashion. Alternatively, multiprocessor clustering has been proposed as an approach to constructing scalable multiprocessors efficiently. With multiprocessor clustering, commodity workstations or personal computers can be grouped together to form a distributed shared memory machine.
As noted above, the performance of multiprocessor systems with a shared bus is limited due to the bottleneck of the bus. Hence, to provide higher bandwidth in such systems, hierarchical buses have been proposed in many machines. See, for example, the above-referenced article by D. Kuck and also U.S. Pat. No. 5,237,673. FIG. 2 shows a representative shared memory multiprocessor system with hierarchical buses. In such systems, each local bus 30 connects its associated processors 32 and local memory 34. Separate shared memory 36 resides on a global bus 38, which can be accessed by the processors 32 on any local bus 30. Although hierarchical buses help improve the bandwidth of shared memory multiprocessors, they still do not scale very well since the global bus causes a performance bottleneck.
Many shared memory multiprocessors based on scalable networks have been proposed or implemented. In addition to the above-referenced articles by D. Leonski and G. Pfister, also refer to A. Gottlieb et al., "The NYU Ultracomputer--Designing an MIMD Shared Memory Parallel Computer," IEEE Transactions on Computers, pp. 175-189, February 1983; KSR, "KSR-1 Overview," Internal Report, Kendall Square Research Corporation, 1991; and U.S. Pat. No. 5,297,265. Some of these machines include a cache coherence protocol to improve its performance on accessing shared memory. However, these machine architectures are not open enough in the sense that their interconnects are proprietary designs, although they may use off-the-shelf processors. With proprietary architectures, the system cost is usually high due to the limited volume of sale. Alternatively, multiprocessor clustering has been proposed to overcome this problem by connecting a group of existing workstations. In a clustered shared memory multiprocessor system, each cluster node has one or more processors, and the global shared memory is partitioned and distributed among the nodes. With multiprocessor clustering, systems can be expanded in a "pay-as-you-go" fashion.
FIG. 3 shows the configuration of a typical cluster node. In such a cluster node, there can be more than one processor 42 (with its local cache memory) on a shared bus 40. There exist two types of memory on the bus: private memory 50 and global memory 52. The private memory 50 can only be accessed by the processors 42 in the local cluster node, while the global memory 52 can be accessed by any processor in the whole system. A memory control unit 43 controls accesses to private memory 50 and a cluster cache and directory 54, which is usually associated with each node, contains the line copies from remote clusters and keeps track of the states of the memory lines and the cache lines in the associated node. A cluster interface 56 is a controller which is in charge of translating transactions between the shared bus 40 and the intercluster networks. It also maintains cache coherence over the intercluster network. A routing switch 58 is used to transmit and receive transaction packets to and from other cluster nodes.
The major problem with the architecture in FIG. 3 is that the additional memory required for the global memory in the system increases the cost of clustering. A separate global memory in the cluster node makes memory utilization inefficient. As described below, a solution to this problem is to borrow a portion of the existing memory in the cluster node for the global memory. | {
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For many years, it has been well known to perforate products manufactured from webs such as paper towels, bath tissue and the like to thereby facilitate the removal of sheets from a roll by tearing. There have been proposed a variety of types of mechanical apparatuses and numerous different methods for forming the perforations for these products. Typically, a moving blade has been utilized to perforate a web as it passes between the moving blade and a stationary anvil wherein the moving blade extends perpendicular to the direction of travel of the web.
While this conventional operation has been widely adopted, there are a number of well known drawbacks in terms of the overall reliability, manufacturing costs, flexibility, and perforation quality. Among the drawbacks is the fact that the interaction of the moving blade and the stationary anvil is known to impose a speed limitation since vibrations produced at high speeds adversely affect the overall quality of the perforations formed in a web. Further, the vibrations caused by the interaction of the moving blade and stationary anvil may result in costly web breaks or equipment malfunctions requiring a shutdown of the manufacturing operation.
For instance, it is known that the teeth on the moving blade become dull or broken after a period of use. This not only will result in an inferior and unacceptable level of perforation quality, but it will also require a temporary shutdown of the manufacturing operation to replace the moving blade and to discard inferior product produced immediately prior to shutdown. As will be appreciated, this results in unacceptable waste and significantly increased manufacturing costs.
In addition, another drawback to conventional equipment has been the inability to quickly change from one perforation pattern format (or sheet length) to another without significant down time for the changeover. It has typically been the case that this type of changeover requires the manufacturing operation to be shut down for at least several hours. While the changeover is occurring, there is obviously no product being produced and personnel must be actively engaged in implementing the changeover, all of which leads to significantly increased manufacturing costs.
In another respect, there has been a continuing need for greater flexibility in order to produce products having enhanced consumer desirability. For instance, it would be desirable to be able to produce both linear and nonlinear perforations as well as perforations extending in both the cross and machine directions. While various approaches have been suggested, none have offered the requisite level of perforation quality that would result in a fully acceptable product.
Additionally, it would be desirable to have perforations that are sufficiently strong to withstand winding of a web but also sufficiently weaken the web at least at the edges to facilitate the separation of one sheet from the next. Further, it would be desirable to have a wound or rolled perforated web product which is manufactured in such a manner that is possible for a line of perforations to complement, register with, or match an embossed or printed pattern on the web.
While various efforts have been made in the past which were directed to overcoming one or more of the foregoing problems and/or to providing one or more of the foregoing features, there remains a need for perforating apparatuses and methods and perforated web products having improved reliability, lower manufacturing costs, greater flexibility, and higher perforation quality. | {
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Generally, a communications platform that transforms audio into an integrated streaming audio webcast is known in the art. End-users are able to participate in the audio webcasts from anywhere on the Internet using just a standard web browser, with the audio being streamed to the user. Streaming media is a type of Internet content that can be played while still in the process of being downloaded. A user's computer can play the first packet of an audio stream, decompress the second, while receiving the third. As such, an end-user can listen to a webcast without waiting until the end of content transmission. Streaming media quality can vary widely according to the type of media being delivered, the speed of the user's Internet connection, network conditions, content encoding, and the format used.
Typically, the media's server, client, and production and encoding tools developed by a streaming software vendor are collectively referred to as a format, Streaming media encoded in a particular format is provided by that format's media server and can be replayed using that format's client. Media clients are also often referred to as ‘players’, and typically exist as plug-ins to Web browsers. Example players include, but are not limited to, Windows Media®, Real Player®, Apple QuickTime® and Adobe Flash®.
Audio webcasts have been used for several years by companies to communicate with investors and security analysts. For example, on Oct. 23, 2000, the Securities and Exchange Commission (SEC) adopted Regulation FD (Fair Disclosure) which provides that when an issuer, or person acting on its behalf, discloses material nonpublic information to certain enumerated persons (in general, securities market professionals and holders of the issuer's securities who may well trade on the basis of the information), it must make public disclosure of that information. Various companies have conformed to Regulation FD by disclosing material nonpublic information to the public using audio webcasts.
Turning now to FIG. 1, a typically audio webcast will be discussed. To begin, at step 10, a customer wishing to initiate a webcast contacts a call provider to schedule an event. At step 12, the call provider, who typically operates an event registration system for scheduling the event, enters the event information into the registration system. Then, at step 14, the call provider confirms the event information and sends the customer a provider Web site address, an event identifier, and a user name and password to use to initiate the conference call. At step 15, either the vendor and/or call provider transmits invitation messages to prospective end-users. The messages are typically included in an e-Mail and include the event identifier sent to the customer, as well as a link to a content distribution Web site. At step 16, the prospective end-users receive the notification. Lastly, at step 18, to access the event, an end-user selects the link included in the e-Mail (or enters a URL manually) to launch his or her browser's media player to listen to the event. To connect and listen to an event, the end-user typically requires a computer with a hardware sound card and Internet connection, an Internet browser (Internet Explorer or Netscape Navigator, or the like), streaming media player (e.g., Windows Media Player, RealPlayer or the like) and the Web site address of the event. At the Web site address of the event, the end-user may enter the event identifier, user name (if required) and password (if required) to access the event. Of course, one or more of the above-described steps can be carried out in a different manner. At any one point in time, several hundred individuals may participate in an audio webcast and multiple audio webcasts, as described in connection with FIG. 1, can occur simultaneously to disseminate material nonpublic information and other information.
Traditional webcast systems, however, have several deficiencies. For example, these systems typically operate on a single computer server, which represents a single point of failure and limits scalability, i.e., the number of users that can listen to the audio of the event. Moreover, the prior art systems require advanced setup for the content streams requiring a significant investment in both computer and telephony infrastructure equipment. Such systems and resources required include, without limitation, racks of telephony equipment, media encoders, storage, network connectivity, and the like. Moreover, this infrastructure is required to be maintained twenty four (24) hours, seven (7) days a week for three hundred and sixty five (365) days in readiness for service. Furthermore, the capacity of this infrastructure needs to exceed the highest possible peak of demand, even if average demand only utilizes a fraction of the equipment. As a consequence, prior art webcast systems require physical production facilities that have inherent cost and scaling issues.
These and other problems of prior art webcast systems are addressed by the present invention. | {
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Electrochemical fuel cells convert reactants, namely fuel and oxidant fluid streams, to produce electric power and reaction products. Solid polymer electrochemical fuel cells generally employ a membrane electrode assembly ("MEA") comprising a solid polymer electrolyte or ion-exchange membrane disposed between two porous electrically conductive electrode layers. The anode and cathode each comprise electrocatalyst, which is typically disposed at the membrane/electrode layer interface, to induce the desired electrochemical reaction.
At the anode, the fuel moves through the porous anode layer and is oxidized at the electrocatalyst to produce protons and electrons. The protons migrate through the ion exchange membrane towards the cathode. On the other side of the membrane, the oxidant moves through the porous cathode and reacts with the protons at the cathode electrocatalyst. The electrons travel from the anode to the cathode through an external circuit, producing an electrical current.
Electrochemical fuel cells can operate using various reactants. For example, the fuel stream may be substantially pure hydrogen gas, a gaseous hydrogen-containing reformate stream, or methanol in a direct methanol fuel cell. The oxidant may be substantially pure oxygen or a dilute stream such as air containing oxygen.
The fuel stream may contain impurities which do not contribute to, and may actually inhibit, the desired electrochemical reaction. These impurities may, for example, originate from the fuel stream supply itself, or may be generated in situ in the fuel cell, for example, as intermediate species during the fuel cell reactions. Further, impurities may enter the fuel stream from elsewhere in the system. Some of these impurities may be chemically adsorbed or physically deposited on the surface of the anode electrocatalyst, blocking the active electrocatalyst sites and preventing these portions of the anode electrocatalyst from inducing the desired electrochemical fuel oxidation reaction. Such impurities are known as electrocatalyst "poisons" and their effect on electrochemical fuel cells is known as "electrocatalyst poisoning". Electrocatalyst poisoning thus results in reduced fuel cell performance, where fuel cell performance is defined as the voltage output from the cell for a given current density. Higher performance is associated with higher voltage for a given current density or higher current for a given voltage.
In the absence of countermeasures, the adsorption or deposition of electrocatalyst poisons may be cumulative, so even minute concentrations of poisons in a fuel stream, may, over time, result in a degree of electrocatalyst poisoning which is detrimental to fuel cell performance.
Reformate streams derived from hydrocarbons or oxygenated hydrocarbons typically contain a high concentration of hydrogen fuel, but typically also contain electrocatalyst poisons such as carbon monoxide. To reduce the effects of anode electrocatalyst poisoning, it is known to pre-treat the fuel supply stream prior to directing it to the fuel cell. For example, pre-treatment methods may employ catalytic or other methods to convert carbon monoxide to carbon dioxide. However, known pre-treatment methods for reformate streams cannot efficiently remove 100% of the carbon monoxide. Even trace amounts less than 10 ppm can eventually result in electrocatalyst poisoning which causes a reduction in fuel cell performance.
Substances other than carbon monoxide are also known to poison fuel cell electrocatalysts. Depending on the type of fuel and the fuel processing methods, impurities in the fuel stream may be present in quantities sufficient to poison the electrocatalyst and reduce fuel cell performance. Fuel cell components and other fluid streams in the fuel cell system may also be a source of impurities which may result in poisoning of the electrocatalyst. For example, fuel cell separator plates are commonly made from graphite. Organic impurities in the graphite may leach out and poison the electrocatalyst. Other poisons may be generated by the reaction of substances in the reactant streams with the fuel cell component materials.
What constitutes a poison may depend on the nature of the fuel cell. For example, whereas methanol is the fuel in a direct methanol fuel cell, in a hydrogen fuel cell operating on a methanol reformate stream, traces of unreformed methanol can be detrimental to the electrocatalyst performance.
Conventional methods for addressing the problem of anode electrocatalyst poisoning include purging the anode with an inert gas such as nitrogen. However, such purging methods involve suspending the generation of power by the fuel cell, thus a secondary power source is needed to provide power while the fuel cell anode is being purged.
Another approach for removing poisons from an electrocatalyst comprises introducing a "clean" fuel stream containing substantially no carbon monoxide (or other poisons) to a poisoned fuel cell anode. Where the adsorption is reversible, an equilibrium process results in some rejuvenation of the electrocatalyst. However, a disadvantage of this approach is that it is generally not effective against irreversibly adsorbed poisons. Furthermore, the recovery of the anode electrocatalyst by such an equilibrium process can be very slow, during which time the fuel cell is not able to operate at full capacity.
Another approach to counteract carbon monoxide electrocatalyst poisoning is to continuously introduce a low concentration of oxygen into the fuel stream upstream of the fuel cell, as disclosed by Gottesfeld in U.S. Pat. No. 4,910,099. However, there are several disadvantages to Gottesfeld's method which influence fuel cell performance and efficiency. For example, an oxygen bleed results in parasitic losses, undesirable localized exothermic reactions at the anode, and dilution of the fuel stream.
It is apparent from the prior art that there is a need for an improved method and apparatus for rejuvenating a fuel cell anode electrocatalyst by removing poisons therefrom, which does not involve suspending the availability of the fuel cell to generate power. | {
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Information technology (IT) systems are generally monitored so that remedial action can fix issues that arise. An information technology system administrator is notified of the system's issues usually through graphs, gauges, dash boards, or other visual indicators that depict the system's conditions. Upon notice of such an issue in the system, the administrator searches for the issue's root cause to resolve the issue as quickly as possible. | {
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Field of the Invention
Embodiments of the present invention relate to the field of manufacturing technologies of display devices, in particular, to a pair of sampling scissors.
Description of the Related Art
In a manufacturing technology of a liquid crystal display (LCD), a rubbing process is typically used to pre-process an aligned film. The rubbing process mainly comprises steps of: placing a substrate coated with a polyimide (PI) film on a bearing platform; rolling, on the bearing platform, a rubbing roller pre-wrapped with rubbing cloth on its surface at a predefined rotation speed so as to drive the rubbing cloth to roll over the PI film of the substrate at a certain pressure; forming an aligned film having slots therein through an interaction between piles on the surface of the friction cloth and the surface of the PI film during the rolling of the rubbing cloth. Once the rubbing process is completed, the substrate is assembled with another substrate, and liquid crystals are poured into a space between the two substrates. An anchoring energy is generated between liquid crystal molecules and the aligned film, thus the liquid crystal molecules are arranged in sequence along the slots, so that an arrangement of the liquid crystal molecules in the aligned film meets the requirement of a pretilt angle.
During the rubbing process, uniformity of the directional arrangement of the liquid crystal molecules and thus a display quality of the LCD display directly depend on the rubbing effect, which is in turn determined by a quality of the rubbing cloth. During manufacture, test and transportation, the rubbing cloth may be damaged such that some impurities in a weaving and dyeing process may present in the rubbing cloth, or the rubbing cloth may have a non-uniform thickness or some other objects may present in the surface of the rubbing cloth, for example. These defects may affect a quality of the piles of the rubbing cloth for forming the slots, which leads to an insufficient resilience of the piles. If the piles are unable to recover during a continuous rubbing, the aligned film at a corresponding rubbing position has a poor uniformity, and an aligned performance is thereby affected.
An existing method for testing the quality of the rubbing cloth comprises steps of: shearing off a sample from the rubbing cloth; placing the sample in a cyclic compressing and recovering device; testing the resilience of the piles of the sample after being compressed repeatedly to determine whether a predefined threshold is met. It is determined that the rubbing cloth corresponding to the sample is able to meet the requirement of the uniformity when performing the rubbing process with the rubbing cloth, if the predefined threshold is met. In prior arts, the sampling is performed through a commonly used scissor. During the shearing process, a pair of scissors are needed to continuously shear the rubbing cloth, so that the piles of the rubbing cloth around the sample will be pressed and thus deformed. And in the same time, during the shearing process, the rubbing cloth needs to be pulled, which further affects the positions and the sequence of the piles, so that the rubbing cloth will not meet the requirement of the uniformity of rubbing alignment. | {
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1. Field of the Invention
This invention relates to an improvement in the tandem liquid pressure control device for an anti-look brake which is used in a motor vehicle, etc.
2. Description of the Prior Art
If the wheels of a motor vehicle are locked by receiving an excessively large braking force as compared with the force of friction occurring between the rim surfaces of the tires and the ground surface, there is every likelihood that a dangerous situation may arise, as the vehicle requires a longer distance before stopping, or it loses its directional stability or proper steerability.
Various kinds of liquid pressure control devices for anti-lock brakes have been proposed to prevent such wheel locking. This type of device mainly comprises a sensor for detecting an increase or decrease in the rotational speed of the wheels, and a control unit adapted for receiving the output of the sensor and producing an appropriate output signal to cause a reduction or rise in the pressure of a liquid which is applied to the distal ends of the brake system.
Canadian Patent No. 1,256,966 discloses a liquid pressure control device for an anti-lock brake which is constructed as shown in FIG. 7 of the accompanying drawings. This device has the advantage that the liquid pressures of the first and second liquid pressure control chambers 2 and 3 forming a tandem arrangement can be controlled simultaneously by a single differential pressure-responding member (driving member) 1. The first and second control valves 7 and 8 which are closed to cut off the supply of liquid pressure from the tandem master cylinder 4 to the front left wheel brake 5 (one of the distal ends of the brake system) and the front right wheel brake 6 (the other distal end of the brake system), respectively, are, however, operationally connected with the liquid pressure control piston 9 (first liquid pressure control piston) and the floating piston 10 (second liquid pressure control piston), respectively. The sequence of the anti-lock operation by the device is, therefore, such that it is only after the upward movement of the differential pressure-responding member 1 and the subsequent upward movement of the liquid pressure control piston 9 and the floating piston 1 that the first and second control valves 7 and 8 are closed.
This arrangement gives rise to a number of problems. If there is a great delay in the response of the differential pressure-responding member 1 which initiates the anti-lock operation, and if the tandem master cylinder 4 has a high rate of liquid supply, the first and second liquid pressure control chambers 2 and 3 and the front left and right wheel brakes 5 and 6 have a great increase in liquid pressure before the first and second control valves 7 and 8 are closed. If the seals 12, 13 and 14 slidably provided about the liquid pressure control piston 9 and the floating piston 10 along the inner wall surface of the braking liquid pressure controlling cylinder 11 are of the V-shaped type, the increase in liquid pressure of the first and second liquid pressure control chambers 2 and 3 brings about an increase in sliding resistance of the seals 12 to 14 to the extent that the liquid pressure control piston 9 and the floating piston 10 fail to follow quickly the vertical movement of the differential pressure-responding member 1. The failure of the floating piston 10 to follow the movement of the differential pressure-responding member 1 leads to a delay in the recovery of a balance of liquid pressure between the first and second liquid pressure control chambers 2 and 3 and in the opening or closing of the first and second control valves 7 and 8. This delay combines with the delay in response of the differential pressure-responding member 1 and makes it still more difficult for the device to achieve any satisfactorily quick control of the liquid pressure which is applied to the brakes. | {
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In recent years, in the art of photomechanical process, it has been desired to use a photographic light-sensitive material excellent in original reproducibility and a processing system which can operate with a reduced amount of waste liquid to be disposed so as to cope with diversification and complexity of printed matters and the increase in environmental awareness.
In order to obtain good reproduction of a halftone image in continuous gradation or of a line work, an image formation system exhibiting an ultrahigh contrast (particularly having a .gamma. value of 10 or more) photographic property is required.
For forming a high contrast image, a lithographic development system employing a so-called "infectious development effect" has been commonly used. However, the lithographic development system is disadvantageous in that the developer is too unstable to be used. An image forming system has been desired in which the photographic light-sensitive material is developed with a processing solution having a good storage stability to obtain an ultrahigh contrast. Examples of such an image forming system are described in U.S. Pat. Nos. 4,166,742, 4,168,977, 4,221,857, 4,224,401, 4,243,739, 4,269,922, 4,272,606, 4,311,781, 4,332,878, 4,618,574, 4,634,661, 4,681,836 and 5,650,746. In this image forming system, a surface latent image type silver halide photographic light-sensitive material comprising a hydrazine derivative incorporated therein is developed with a stable MQ or PQ developer having a Ph value of from 11.0 to 12.3 to obtain an ultrahigh negative image having a .gamma. value of more than 10. In accordance with the method, an ultrahigh contrast and a high photographic sensitivity can be obtained. Further, since a sulfite can be added to the developer in a high concentration, the developer thus obtained exhibits a remarkably improved stability against air oxidation as compared with the conventional lith developers.
The above described method makes it possible to use a sulfite preservative in a high concentration to increase the stability of the developer. However, in order to obtain an ultrahigh contrast photographic image, it is necessary to employ a developer having a relatively high pH value. Such a developer having a relatively high pH value is liable to air oxidation. Thus, it is necessary that the developer be replenished at a high rate. Therefore, some attempts have been made in order to realize an ultrahigh contrast photographic image forming system comprising the nucleation development with a hydrazine compound by using a developer having a lower pH value.
U.S. Pat. No. 4,269,929 (corresponding to JP-A-61-267759 (the term "JP-A" as used herein means an "unexamined published Japanese patent application")), U.S. Pat. No. 4,737,452 (corresponding to JP-A-60-179734), U.S. Pat. Nos. 5,104,769, 4,798,780, 4,998,604 and 4,994,365, JP-A-1-179939, JP-A-1-179940 and JP-A-8-272023 describe a process which comprises the use of a hydrazine nucleating agent having high activity and a nucleation accelerator in order to obtain an ultrahigh image with a stable developer having a pH value of less than 11.0. It is also described that a chemically-sensitized silver halide emulsion having a high silver chloride content has high nucleation activity.
However, another problem encountered when the above described highly active hydrazine nucleating agent, highly active nucleation accelerator or highly active emulsion is employed is the occurrence of a so-called processing unevenness which is density unevenness caused in outputting at defined dot area.
Also, the photographic light-sensitive material containing the highly active hydrazine nucleating agent described above is troublesome in the preservation thereof for a long period of time since the highly active hydrazine nucleating agent is disadvantageously liable to decompose.
Further, although the amount of replenishment for developer and the amount of waste liquid in processing decrease to a certain extent using the stable developer having a pH value of less than 11.0, still further reduction is required. Therefore, a photographic light-sensitive material having higher processing stability, which has less change in photographic properties due to fluctuation of pH of a developer has been desired.
The incorporation of a hydrazine nucleating agent into fine polymer particles to add to a coating solution is described in JP-A-2-948. However, a purpose of the technique is prevention of deposition of the hydrazine nucleating agent. | {
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1. Field of the Invention
The present invention relates to an optical medium such as optical recording media with which the recording of information or the playback of information recorded on an optical disk or the like can be performed.
2. Description of the Related Art
In an effort to increase recording capacity, a new type of optical disk called a bonded optical disk has been proposed in recent years, in which two disk substrates are used, each comprising a recording layer formed on a transparent resin substrate, and these two disk substrates are bonded with an adhesive layer sandwiched therebetween.
Hot-melt adhesives and radical polymerizable UV-curing adhesives, for example, have been used as the material for the adhesive layer that holds the disk substrates together in these bonded optical disks, but these could not be considered practical because of their poor heat resistance and warping of the disk substrates.
In view of this, the use of a liquid cationic polymerizable UV-curing adhesive has been proposed, as discussed in, for instance, Japanese Laid-Open Patent Application H7-126577. These cationic polymerizable UV-curing adhesives are expected to provide a huge improvement to the manufacturing process because the curing reaction proceeds upon irradiation with UV rays even in the air or in the dark, and because of the less shrinkage during the reaction, other benefits are less warping of the disk substrates and sufficient adhesive strength after curing.
Thereupon, the applicant proposed adding a so-called ion catcher (or ion exchanger) to a resin composition in an effort to prevent corrosion of the recording layer in high temperature and humidity environments when one of these cationic polymerizable UV-curing adhesives is used (Japanese Patent Application H8-59555).
This addition of an ion catcher allows ionic substances in the adhesive layer to be trapped, so the effect is better corrosion resistance.
However, because of the high light-proof property of the ion catcher, the UV rays cannot pass sufficiently into the interior of a UV-curing resin if the ion catcher is added in too large an amount, so the reaction efficiency is poor in the curing of the adhesive agent.
In order to solve the above problems, the present invention provides an optical medium with better corrosion resistance, which is accomplished by using an adhesive agent that has no detrimental effect on the recording layer in an optical medium.
The optical medium of the present invention has a recording layer and an adhesive layer between at least two substrates, wherein the adhesive layer contains (A) a cationic polymerizable resin, (B) a photo-initiator, and (C) an anion catcher.
In another aspect of the present invention, the weight ratio of the photo-initiator (B) and the anion catcher (C) in the above-mentioned optical medium is from 3:1 to 3:24.
In another aspect of the present invention, the weight ratio of the photo-initiator (B) and the anion catcher (C) in the above-mentioned optical medium is from 3:1 to 3:12.
With the above structure of the present invention, because the adhesive layer contains a cationic polymerizable resin (A) and a photo-initiator (B), the curing reaction proceeds upon irradiation with UV rays or other light, and there is also less shrinkage during the reaction.
Furthermore, because the anion catcher (C) is contained, chlorine ions and other ions contained in the resin can be removed more effectively, and this suppresses the corrosion of a reflective layer or recording layer by these ions.
Corrosion of a reflective layer or recording layer of the optical medium by ions can be suppressed particularly well when the weight ratio of the photo-initiator (B) and the anion catcher (C) is from 3:1 to 3:24.
Moreover, if the weight ratio of the photo-initiator (B) and the anion catcher (C) is from 3:1 to 3:12, an adhesive layer with good reactivity will be obtained, so this optical medium can be produced more efficiently in the manufacturing process. | {
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This invention relates to a self-sustaining solenoid in which a plunger is retracted by a supply of an operating current and held at its retracted position even after cutting off of the operating current and moved back upon application of a return current.
In conventional types of self-sustaining solenoids, when an operating current is applied to a coil, the plunger is attracted into the coil to butt against a permanent magnet fixed to one inner end of the coil and, even after cutting off of the operating current, the plunger is retained on the permanent magnet by its magnetic attractive force. By applying to the coil a current reverse in direction from the operating current to apply to the permanent magnet a magnetic field opposite to the direction of magnetization of the permanent magnet the attractive force of the permanent magnet is reduced and the plunger is pulled out of the coil to its original position, for example, by the force of a return spring imparted to the plunger beforehand.
Since the prior art self-sustaining solenoid has such a construction that during operation the plunger makes direct contact with the permanent magnet as described above, the permanent magnet is liable to be broken. Further, an oxide magnet has been used, as the permanent magnet, which has a relatively large coercive force and a Curie temperature above 450.degree. C. and is difficult of demagnetization. The magnetization of such a permanent magnet is not affected by the application thereto of the magnetic field based on the operating current or return current. Accordingly, when the plunger stays in its restored state, it is likely to be attracted by the permanent magnet if moved a little by mechanical vibration or shock towards the permanent magnet. If the force of the return spring is made large to avoid the possibility of such accidental attraction of the plunger by the permanent magnet, it is necessary to increase the number of turns of a coil for attracting the plunger against the return spring during operation, and further, means for holding the plunger at its restored position inevitably becomes bulky, resulting in the overall size of the device being increased.
It is an object of the present invention to provide a self-sustaining solenoid which is long-lived even if used frequently.
Another object of the present invention is to provide a self-sustaining solenoid which can be constructed small.
Another object of the present invention is to provide a self-sustaining solenoid which stably maintains its restored states even if subjected to mechanical vibration or shock and which can be constructed small.
Yet another object of the present invention is to provide a self-sustaining solenoid which is hardly affected by an ambient temperature change or power source voltage fluctuation. | {
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1. Technical Field
The present invention relates to an object identifying method, an object identifying device, and a mobile phone for shooting an object to be shot such as the face, the iris or the palm mark of a human being to identify the object.
2. Related Art
As a system for identifying the person himself or herself, various kinds of identifying systems have been hitherto proposed. For instance, exemplified are a face identifying system for shooting a face to identify the face of the person himself or herself, an iris identifying system for shooting an iris to identify the iris of the person, a palm mark identifying system for shooting a palm mark to identify the palm mark of the person, etc.
These identifying systems serve to identify the person himself or herself by shooting an object to be shot such as the face, the eye or the hand. Thus, an impersonation by photographs or a wrong recognition needs to be rejected.
As a method for rejecting the impersonation or the wrong recognition, an individual identifying device for matching a plurality of objects is proposed (see JP-A-2003-36442). In the individual identifying device, not only a plurality of matching is matched, but also a matching process is carried out again when there is an indefinite part so as to suppress a wrong recognition rate to a low level.
However, when a plurality of matching processes is performed, a problem arises that not only much processing time, but also a labor is required for a user. | {
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The background description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent the work is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
Voltage regulators are used in electronic devices to maintain relative steady supply voltages to drive load devices. In an example, an AC power supply is provided to an electronic device. The electronic device includes a rectifier to rectify the AC voltage, and a voltage regulator to regulate the rectified AC voltage to generate a steady DC voltage. The DC voltage is used to drive, for example, integrated circuits (IC) in the electronic device. | {
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The invention relates to a railway track tamping machine, especially a track levelling and aligning machine which is equipped with at least one ballast tamping unit which is longitudinally movably mounted on the machine frame and has at least one pair of co-operating tampers which are vertically adjustable.
Track tamping machines which proceed with a uniform velocity and on which intermittently working longitudinally movable tamping units are mounted are already known, see German published application No. 1,067,837 and U.S. Pat. No. 3,455,249. These machines are different from conventional track tamping machines which move in steps from tie to tie and, therefore, need to be accelerated very quickly as well as decelerated very quickly. Machines of which the frame is uniformly moved and on which only the tamping units have to move periodically, have the advantage that the masses to be accelerated and to be decelerated at each tamping cycle are considerably smaller than the step moving machines and the necessary energy and forces to move these masses are consequently smaller. Known uniform movement track tamping machines have tamping units longitudinally movable along the machine frame. Such arrangements are afflicted with adjustment problems. After completing the tamping of one tie and having lifted the tamping tools above the level of the rails, the tamping units have to be moved from the rear end position of the track travel on the machine chassis quickly into the front end position on the machine frame and be lowered into the track. During the succeeding tamping cycle the tamping units must be moved relative to the frame backwardly at a speed appropriate to the forward speed of the machine frame. The control of such relative movement and the adjustment of the tamping unit into the correct working position presents difficulties, particularly if the tamping unit is suspended in guides for sliding movement on the machine frame.
The same disadvantages are found in principle with another known track tamping, levelling and aligning machine see Austrian Patent No. 350,612 which comprises a main frame and an additional frame which is coupled to the main frame by a longitudinal moving device so that part of the machine can be moved with uniform speed and another part of the machine can be moved in step-wise sequence.
The present invention seeks to simplify the machine as well as the control of the workheads. | {
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Imaging devices are used to support a diagnosis and therapies of many medical diseases. New imaging techniques like Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) are becoming more and more popular. X-ray technology and devices which have been known in their basic principles since 1890, are still being used because they provide medical images very fast and with high resolution. The disadvantage of these traditional X-ray systems is the lack of digital and/or 3D image capabilities.
Approximately in 1980 the first digital angiographic X-ray imaging systems came into use. Such an X-ray system is disclosed in U.S. Pat. No. 4,504,858 “X-Ray Diagnostic System for Angiographic X-Ray Examination”. One of the first commercial products was the Digitron from Siemens in 1983.
Approximately since 1995 the first angiographic X-ray imaging system has been in use which allows 3D imaging of static objects, in particular of humans organs. Parts of such an X-ray system are disclosed in U.S. Pat. No. 5,963,613 “C-arm Calibration Method for 3 D Reconstruction in an Imaging System”. These systems use an X-ray source and an X-ray detector mounted on a C-arm which rotates within a predetermined angle (usually around 220 degrees) around the patient to collect a number of two-dimensional X-ray projections. Before acquiring this data, a contrast agent is injected into a vessel of an organ which will be examined, for example the vessels of the brain. The two-dimensional X-ray projections are transferred to a special processor, usually an additional computer workstation, for reconstruction of a 3D volume image.
In the 1990s the X-ray detectors were image intensifiers, which since the beginning of the century have been more and more replaced by flat-panel X-ray detectors, usually based on amorphous silicon (aSi). The benefit of the flat-panel detectors are larger image size, a better access to the patient and a better image quality. Although the lower weight of the flat-panel detector allows faster rotating speed of the C-arm, these possibilities have not been really used. A typical product which allows 3D high contrast imaging is the AXIOM Artis dTA, with the syngo InSpace 3D Workstation from Siemens.
In 2006 the first C-arm X-ray system which provided CT-like imaging, particular low contrast imaging, was introduced to the medical market by the Siemens AG and called DynaCT. This solution is disclosed in US2006/0120507, “Angiographic X-ray Diagnostic Device for Relational Angiography”. This document, however, does not disclose any clinical protocols and procedures. A clinical protocol and/or a procedure comprises any medical method and/or means including a method for anamnesis, diagnostics, prophylaxis, treatment and monitoring of a patient.
DE 10 2005 016 472 A1 “Betriebsverfahren für eine Röntgenanlage, korrespondierendes Betriebsverfahren für einen Rechner und entsprechende Gegenstände” discloses an X-ray system which allows through a particular synchronization with the ECG of the patient, that CT-like imaging of the heart particular low contrast imaging can be reconstructed.
These above mentioned X-ray systems are having an user interface and several control elements to select technical parameters of the system. The drawback is that the user needs to have a technical understanding of the system to operate it properly. In most cases the user even needs to set on different subsystems and components specific parameters e.g. the voltage and current on a generator control, the parameters for 3D high-contrast imaging on an imaging subsystem, the parameters for 3D low contrast imaging on a separate computer workstation and a parameter for a injection protocol on a contrast media injector.
This situation today is close to the first cars, if the driver wanted a specific performance, e.g. during cold and moist weather, he had to reduce the gap of the electrodes in the spark plug and change additionally the ignition timing during the driving. | {
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It has heretofore been realized that speech recognition circuitry coupled with a computer can be used to great advantage in a wide variety of tasks. Typically, the interface between a computer and a human operator has been a mechanical keyboard. Prior art keyboard interfaces had a number of disadvantages including slow speed, expense, the need for training for the operator and the limitations that the operator's hands were fully occupied and could not be used for other purposes. Thus, despite the apparent advantages of human-machine speech-display real time interaction, only limited success has been achieved to date. Numerous obstacles must be overcome before a successful speech recognition process can be implemented at a reasonable cost. A number of problems in designing such a system include the variability of speech from one person to another, the need to produce an accurate template representing each speech unit and the need for a high speed computer having rapidly accessible mass memory to handle the size of vocabulary needed for a useful application.
There exists a need for a human-machine interactive instructional process in which the process is essentially independent of the speaker, and in which the student is able to proceed at his or her own rate sequentially through rote learning and testing steps.
It is an object of the present invention to devise a method of human-machine voice-display interactive instruction with the aid of a digital computer which is quite flexible, and can be used as easily for first graders as for college seniors or workers. It is a further object of the present invention to devise a method which can be used for either individualized or generalized tutoring, practice and testing and which motivates students to desire to study and learn. It is a further object of the present invention to develop a method which frees instructors from the task of teaching by rote, affording the opportunity of additional time for individual instruction or lesson planning, and yet which requires no expensive computer training in order for the instructor to design computer lessons. It is a further object of the subject invention to introduce children to computers in an unobtrusive manner and to provide a process whereby students can talk to the computer in their plain language. It is a further object of the present invention to produce a method which provides positive reinforcement at each step of the lesson for the students and which monitors the student's progess, providing a report card for the instructor. | {
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1. Field of the Invention
The present invention relates to a reproducing circuit of a wobble signal recorded on a recordable disk of an optical disk.
2. Description of the Related Art
At present, a write once optical disk such as a CD-R/DVD-R, and a recordable optical disk such as a CD-RW/DVD-RW or DVD-RAM, in addition to a read-only optical disk such as a CD or a DVD-RAM, are put on the market. At the time of recording of these recordable optical disks, clock signal generation from a reproduction signal, which is performed in a conventional read-only disk, can not be performed. Thus, a groove as a portion where information is recorded on a disk is wobbled at a constant period, and a clock signal at the time of recording is generated from a wobble signal obtained by reproducing this wobbling (hereinafter referred to as wobble) by a push-pull system.
FIG. 2 shows a conventional example of a wobble signal reproducing circuit. Reflected light from a laser spot irradiated on a disk forms a far field pattern 2 on an optical detector 1 divided in two. Two outputs of the optical detector are subtracted by a subtracting circuit 17 to take out a push-pull component. From the obtained push-pull signal, a wobble frequency is extracted by a band pass filter (BPF) 18. A wobble signal reproduced from a CD-R/RW is a continuous signal of a frequency of 22.05 KHzxc2x11 KHz. In the CD-R/RW, since address information called ATIP (Absolute Time In Pregroove) is superimposed on the wobble signal by FM modulation, it has a width in frequency band. FIG. 3 is a view showing a disk surface of a DVD-R/RW. Reference numeral 301 in the drawing designates a groove in which data is recorded and which is wobbled similarly to the CD-R/RW. A wobble signal reproduced in the DVD-R/RW is a continuous signal of a single frequency of 140.65 KHz different from the CD-R/RW, and address information is not superimposed. Instead thereof, a pit called a land pre-pit (hereinafter referred to as an LPP) designated by 302 is recorded in a land portion which is between a groove and a groove and in which information is not recorded. The LPP exists in a region from the head of maximum amplitude position of a wobble to the third, and address information is recorded by this three bits.
In order to stably extract the wobble signal from the push-pull signal, it becomes necessary to reduce leakage of an RF signal to the push-pull signal. Thus, as disclosed in Japanese Patent Unexamined Publication No. Hei. 8-194969, it is conceivable that an automatic gain control circuit (AGC circuit) is provided at a front stage of the subtracting circuit of FIG. 2.
Besides, in recent years, as the capacity of a disk is increased, doubling of the speed of disk reproduction becomes active.
In double speed reproduction, it becomes necessary to change over the pass band of the BPF of wobble in connection with the double speed. As a method of causing this connection, although it is conceivable that setting of the pass band of the BPF is changed over by a microcomputer according to the reproducing speed of a disk, since access to the microcomputer becomes necessary each time the speed is changed, the processing becomes troublesome. In the case where CAV reproduction is performed with an increase in speed of disk reproduction, a deviation in band setting of the BPF occurs by the restriction on the number of accesses to the microcomputer, and this becomes a factor of a drop in S/N of the wobble signal and an increase in clock jitter due to that. With respect to this problem, as disclosed in Japanese Patent Unexamined Publication No. Hei. 11-203681, it is conceivable to use pass band automatic tracking by a dummy filter and a phase comparison circuit.
As set forth above, in the case where double speed reproduction of various disks is realized by one optical disk reproducing device, since the specifications of the respective disks are different, various problems occur. The problems of a wobble signal reproducing circuit are as follows:
1. Leakage of a Land Pre-pit Signal of a DVD-R/RW into a Wobble Signal
Here, in the case where the AGC (AUTOMATIC GAIN CONTROL) circuit is disposed at the front stage of the subtracting circuit of FIG. 2 as disclosed in Japanese Patent Unexamined Publication No. Hei. 8-194969, at the time of reproduction of a DVD-R/RW, an LPP signal leaks into an RF signal, and an AGC (AUTOMATIC GAIN CONTROL) gain is varied in accordance with the amplitude variation. Thus, there is a fear that the RF signal at the time of passing through the LPP leaks into the wobble signal.
2. The Processing for Lack of a Wobble Signal in an Address Information Region of a DVD-RAM
FIG. 4 is a view showing a disk surface of a DVD-RAM. Reference numeral 403 in the drawing designates a groove; and 404, a land. In order to raise recording density, the DVD-RAM adopts a land groove recording system in which signals are recorded in both the groove 403 and the land 404. Thus, address information in the DVD-RAM is recorded in a staggering manner with respect to respective tracks of the land and the groove as indicated by 401 and 402 of the drawing. The portion where the address information is recorded is called a PID (Physical Identification Data) region.
Although a wobble signal reproduced in the DVD-RAM has a single frequency of 157 KHz similarly to the DVD-R/RW, since the address information is recorded in the staggering manner in the PID region, when a push-pull component is detected and is subtracted, it lacks a signal at one side before the subtraction. Thus, similarly to the above item 1, in the case of considering provision of the AGC (AUTOMATIC GAIN CONTROL) circuit at the front stage of the subtracting circuit, it is conceivable that the AGC (AUTOMATIC GAIN CONTROL) is saturated in the PID region.
Besides, the wobble signal reproduced in a CD-R/RW has a band width, and the amplitude is varied. In order to reduce an offset due to that at binarization at a later stage, as disclosed in Japanese Patent Unexamined Publication No. Hei 11-161961, it is conceivable that an AGC (AUTOMATIC GAIN CONTROL) circuit is provided at a later stage of the BPF 18. However, in the DVD-RAM, since the groove does not exist in the PID region, it lacks the wobble signal at the time of reproduction of the PID region. Thus, similarly to the above, it is conceivable that this AGC (AUTOMATIC GAIN CONTROL) circuit is saturated in the PID region.
3. BPF Pass Band Setting
In the technique disclosed in Japanese Patent Unexamined Publication No. Hei 11-203681, there are a problem of accuracy of wobble signal band detection in the dummy filter and the phase comparison circuit, and a problem that a circuit scale is increased in order to improve the accuracy of the circuit. In the case where band setting of the BPF is made to follow a clock signal reproduced from a wobble signal, it becomes a problem that a ratio of a wobble signal frequency to a clock frequency is different according to the kind of a disk.
Like this, since the specifications of the wobble signals are different according to the disks, there has been a problem that in the case where the wobble signal reproducing circuits corresponding to the respective disks are provided, a circuit mounting area is increased.
In order to solve the above problems, in a wobble signal reproducing circuit for reproducing a wobble signal recorded by wobbling a groove formed on a disk, the wobble signal reproducing circuit includes an arithmetic circuit for calculating a push-pull signal, a band pass filter for extracting a wobble frequency component from an output of the arithmetic circuit, an AGC (AUTOMATIC GAIN CONTROL) circuit disposed at a front stage or inside of the arithmetic circuit, and land pre-pit detection means for detecting a land pre-pit region where a pit is formed in a land portion which is between the groove and a groove and in which information is not recorded, and a structure is such that a gain of the AGC (AUTOMATIC GAIN CONTROL) circuit is fixed or a response time constant of the AGC (AUTOMATIC GAIN CONTROL) circuit is changed over by a detection signal of the land pre-pit detection means at a time of reproduction of the land pre-pit region.
Besides, there is provided address information recording region detection means for detecting an address information recording region where an address is formed in a portion in which the groove is divided on a track into a land portion, and a structure is such that a gain of the AGC (AUTOMATIC GAIN CONTROL) circuit is fixed or a response time constant of the AGC (AUTOMATIC GAIN CONTROL) circuit is changed over by a detection signal of the address information recording region detection means at a time of reproduction of the address information recording region.
Further, there is provided a second AGC (AUTOMATIC GAIN CONTROL) circuit at an output of the band pass filter for extracting the wobble signal from the push-pull signal, and a structure is such that a gain of the AGC (AUTOMATIC GAIN CONTROL) circuit and a gain of the second AGC (AUTOMATIC GAIN CONTROL) circuit are fixed or a response time constant of the AGC (AUTOMATIC GAIN CONTROL) circuit and a response time constant of the second AGC (AUTOMATIC GAIN CONTROL) circuit are changed over at a time of reproduction of the address information recording region.
Besides, there is provided means for detecting a scratch or a finger print of a disk to be reproduced, and a structure is such that a gain of the AGC (AUTOMATIC GAIN CONTROL) circuit is fixed or a response time constant of the AGC (AUTOMATIC GAIN CONTROL) circuit is changed by an OR operation output of a detection signal of the means and a detection signal of the land pre-pit detection means.
Further, a structure is such that a gain of the AGC (AUTOMATIC GAIN CONTROL) circuit and a gain of the second AGC (AUTOMATIC GAIN CONTROL) circuit are fixed or a response time constant of the AGC (AUTOMATIC GAIN CONTROL) circuit and a response time constant of the second AGC (AUTOMATIC GAIN CONTROL) circuit are changed by an OR operation output of a detection signal of means for detecting a scratch or a finger print of a disk to be reproduced and a detection signal of the address information recording region detection means.
Besides, the land pre-pit detection means detects a land pre-pit recording region by a detection signal corresponding to a land pre-pit region position or the signal generated from the detection signal of the means and a clock obtained in synchronization with a rotation speed of the disk.
Further, the address information recording region detection means detects an address information recording region by a detection signal corresponding to an address information recording region position, the signal generated from the detection signal and a wobble signal, or the signal generated from the detection signal of the means and a clock obtained in synchronization with a rotation speed of the disk.
Besides, a pass frequency band of the band pass filter is substantially in proportion to a frequency of a clock obtained in synchronization with a rotation speed of the disk, and a proportionality coefficient between the pass frequency band and the frequency of the clock can be changed. Further, there are provided a scratch detection circuit for detecting a scratch or a finger print of the disk, and a function for fixing the pass frequency band of the band pass filter at a time of detection of the scratch.
Besides, there is provided a function in which a frequency of a clock obtained in synchronization with a rotation speed of the disk is measured and a pass frequency band of the band pass filter is fixed when the frequency is largely varied at a time of normal reproduction.
Besides, an arithmetic circuit for calculating a push-pull signal has a band for permitting a land pre-pit signal of a land pre-pit region to pass, and there is provided land pre-pit detection means for making the output of the arithmetic circuit the land pre-pit signal.
Further, a wobble signal reproducing circuit includes an arithmetic circuit for calculating a push-pull signal, a band pass filter for extracting a wobble signal frequency component from an output of the arithmetic circuit, and a subtracting circuit for subtracting an output of the band pass filter from the output of the arithmetic circuit, and a structure is such that the arithmetic circuit and the subtracting circuit have bands for permitting a land pre-pit signal of a land pre-pit region to pass, and there is provided land pre-pit detection means for making the output of the subtracting circuit the land pre-pit signal. | {
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1. Field of the Invention
The present invention relates generally to fasteners and more specifically to fastening systems accommodating a variability in fastening position.
2. Disclosure Information
In the automotive fastening arts, the wide variability in the positioning of structures to be fastened together necessitates the accommodation of a stack-up of tolerances between automotive body structure and the components that are assembled to an automotive body. One exemplary area is that of the fastening of steering column support bracketry to instrument panel structure. A very early example of such fastening is found in U.S. Pat. No. 1,611,302 to Bourgon which shows a rigid mounting technique used early in the industry. A modern approach is that illustrated in U.S. Pat. No. 3,373,965 to Bien et al. in which axial flexibility is given to the mounting of a clamp suspended with respect to a fixed bracket below an instrument panel.
The steering columns illustrated in these older patents and other automotive componentry generally uses brackets or other attaching devices which must be joined to a panel structure of the vehicle by insertion of some axial locking fastener through an aperture formed through the panel. None of the prior art devices have been found suitable for accommodating variability in positioning of the componentry in the panel with respect to the three mutually perpendicular axes of a Cartesian coordinate system. | {
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A portion of the disclosure of this patent document contains command formats and other computer language listings, all of which are subject to copyright protection. The copyright owner, EMC Corporation, has no objection to the facsimile reproduction by anyone of the patent document or the patent disclosure, as it appears in the Patent and Trademark Office patent file or records, but otherwise reserves all copyright rights whatsoever.
The invention relates generally to management of multiple volumes of data distributed throughout a data storage environment, and more particularly to a system and method for management of device labels used by host systems that interact with data storage systems, when such labels are written as data and distributed over more than one device.
As is known in the art, computer systems generally include a central processing unit (CPU), a memory subsystem, and a data storage subsystem. According to a network or enterprise model of the computer system, the data storage system associated with or in addition to a local computer system, may include a large number of independent storage devices, typically disks housed in a single enclosure or cabinet. This array of storage devices is typically connected to several computers or host processors over a network or via dedicated cabling. Such a model allows for the centralization of data that is available to many users but creates a critical hub for operations.
Recently, disk redundancy has evolved as an alternative or complement to historical backups of the information stored on this critical hub. Generally speaking, in a redundant system, two storage devices, such as disk storage devices, data is copied and stored in more than one place. This allows the data to be recovered if one storage device becomes disabled. In a basic approach, a first disk storage device stores the data and a second disk storage device stores a point-in-time copy of that data. Whenever a data transfer is made to the first disk storage device, the data is also transferred to the second disk storage device. Typically, separate controllers and paths interconnect the two disk storage devices to the remainder of the computer system.
While mirroring has important advantages, it may lead to problems in certain circumstances when all of data including some that is unique to the physical storage device itself is replicated. In particular some host computers use a proprietary operating system that internally manages data storage devices by using xe2x80x9clabels,xe2x80x9d which are typically host-written character strings or some other technique to internally identify disks. For example hosts operating under the Microsoft Windows NT operating system does not allow duplicate labels. This creates problems when data is replicated from one device to another and the labels are replicated as well. When the label is so replicated to at least one other device, the host can encounter two devices carrying the same identification information and treat that as an error.
What is needed is a way to prevent such errors occurring at a host interacting with a data storage system in which data is distributed over one or more disks but while still allowing mirror copying of data to occur.
The present invention is a system and method for management of device identification that is treated as device data, when such data is replicated from one storage device to at least one other storage device.
In one aspect of the invention, the data storage system is configured with logic that enables a method of changing a host-written label, denoted as xe2x80x9cre-labelingxe2x80x9d for a logical volume. Such a logical volume in a preferred embodiment may be one created for continuing business operations while other activities occur that use a copy of the data on the logical volume, wherein such logical volumes may be denoted as a xe2x80x9cbusiness continuance volume (BCV).xe2x80x9d
Re-labeling changes the label originally written by the host on one device and replicated to another device, which received a point-in-time copy of the first device""s data. The re-labeling takes place during a certain operation that takes the BCV offline to a host computer in communication with the data storage system. In the preferred embodiment, the operation that takes the BCV offline is referred to as a xe2x80x9csplit with re-labelxe2x80x9d operation. This re-labeling avoids labeling errors that could arise when duplicate labels result from at least one of the following situations: (i) following a split operation, wherein the BCV has a copy, i.e., an exact replica, of the data from a standard device which has been copied to the BCV; including the identifying label, or (ii) following an operation to xe2x80x9crestorexe2x80x9d the standard device from a device (such as a BCV) having a copy of data originally copied from the standard device. This invention is also useful when a single host encounters two volumes, each distributed, respectively, over a local and remote system. | {
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Field of the Invention
The present disclosure relates to a touch technology, and more particularly to a touch device and fabrication method thereof.
Description of the Related Art
In recent years, touch devices have been widely applied in a variety of electronic products such as mobile phones, personal digital assistants (PDA) or pocket personal computers (PC) and the like. Currently, there exist thin and light touch devices, which comprise a protective cover and a touch component that is directly attached onto a side of the protective cover. The side of the protective cover is provided for users to touch for inputting information or controlling the electronic product. Thus, the protective cover provides a protective function and also a new carrying function for the touch component, thereby omitting the touch substrate that was originally used for carrying the touch component. The touch panel has become more and more popular because it is thin and light.
The foregoing thin and light touch device generally comprises a sensing area for users to manipulate, and a peripheral area surrounding the sensing area. A black shading layer is first formed on the peripheral area of a protective cover, a sensing electrode layer is then formed on the sensing area of the protective cover and a part of the peripheral area, and then a signal transmission line layer, electrically connected with the sensing electrode layer, is formed on the black shading layer to transmit electrical signal produced on the sensing electrode layer to an external detecting circuit through the signal transmission line layer. Touch positions are next determined by the external detecting circuit. Due to certain thickness of the black shading layer, the sensing electrode layer disposed on the peripheral area, and the sensing electrode layer disposed on the sensing area have a certain height difference, namely, the sensing electrode layer in the peripheral area is overlaid on the black shading layer as a ladder, resulting in resistance of the sensing electrode layer, which impacts the touch detection precision. | {
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The present invention relates to hinges, and more particularly relates to a book cover hinge assembly for connecting the front cover of a book or the like to its back cover.
FIG. 1 illustrates a book cover hinge assembly according to the prior art, which is generally comprised of a casing 11 with hooks 111, a clip holder 12 with hook holes 121. The hooks 111 on the casing 11 are respective hooked in the hook holes 121 on the clip holder 12, and therefore the clip holder 12 is fastened to the casing 11. The clip holder 12 further comprises two opposite pairs of knuckles 122, into which pivot pins 13 are respectively inserted and partly engaged into knuckles 31 on the book covers 3 to be fastened. The knuckle 31 of each book cover 3 has gaps 32 on two opposite ends thereof, which allow the knuckle 31 to be expanded as respective pivot pins 13 are inserted. One disadvantage of this structure of book cover hinge assembly is that the pivot pins 13 may easily disconnect from the knuckles 122,31. Another disadvantage of this structure of book cover hinge assembly is that the casing 11 and the clip holder 12 are made for fastening book covers of a specific size. Therefore, different casings 11 and clip holders 12 must be used for fastening book covers of different sizes. | {
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The present invention relates to a spark ignition type stratified charge combustion internal combustion engine.
When injecting fuel in a diesel engine, part of the fuel immediately evaporates and forms a preliminary air-fuel mixture while the remaining fuel is made to diffuse in a combustion chamber in the form of fuel droplets. Next, the preliminary air-fuel mixture is made to self-ignite. This forms a heat source for successive combustion of the fuel vaporizing from the fuel droplets. That is, diffusion combustion is performed. In this case, if the ratio of the preliminary air-fuel mixture becomes too great, explosive combustion will occur, so the combustion temperature will sharply rise and therefore a large amount of NOx will be produced.
Therefore, known in the art is a diesel engine designed so that a combustion pressure sensor and spark plug are arranged in the combustion chamber, the ratio of the preliminary air-fuel mixture is found from the detected combustion pressure, when the ratio of the preliminary air-fuel mixture becomes greater than an optimum value, the spark timing is advanced to cause the spark plug to make the preliminary air-fuel mixture ignite before the amount of generation of the preliminary air-fuel mixture increases excessively, and when the ratio of the preliminary air-fuel mixture at the time of ignition by the spark plug becomes smaller than the optimum value, the spark timing is delayed to make the preliminary air-fuel mixture ignite by the spark plug when the amount of generation of the preliminary air-fuel mixture increases to a suitable amount (see Japanese Unexamined Utility Model Publication (Kokai) No. 2-141648).
On the other hand, in a spark ignition type internal combustion engine as well, when the pressure and temperature in the combustion chamber become extremely high, self-ignition occurs. If self-ignition occurs in a spark ignition type internal combustion engine, however, the entire preliminary air-fuel mixture will burn all at once, so the pressure and temperature in the combustion chamber will rapidly rise and as a result not only will knocking occur, but also a large amount of NOx will be produced. Therefore, in the past, spark ignition type internal combustion engines have been designed as much as possible so as not to allow self-ignition and so that the air-fuel mixture is made to burn by the flame of ignition by a spark plug.
If self-ignition occurs, however, as explained above, knocking occurs and a large amount of NOx will be produced. Combustion by self-ignition, however, is completed in a short time. Therefore, if combustion by self-ignition is caused, the thermal efficiency rises. Therefore, if it were possible to cause combustion by self-ignition without causing knocking and the production of a large amount of NOx, a practical internal combustion engine with a high thermal efficiency could be obtained.
Whether or not knocking and production of a large amount of NOx are caused when combustion by self-ignition occurs, however, depends on the amount of the preliminary air-fuel mixture able to be burned by self-ignition and the combustion time. That is, if the entire preliminary air-fuel mixture is burned all at once, as explained above, knocking and production of a large amount of NOx will occur. If however not all of the preliminary air-fuel mixture, but only part of the preliminary air-fuel mixture is made to burn by self-ignition and the preliminary air-fuel mixture is made to burn by self-ignition little by little with a time lag, the pressure and temperature in the combustion chamber will not rise that much and therefore knocking and production of a large amount of NOx will no longer occur. If the amount of the preliminary air-fuel mixture burned by self-ignition in this case is too small, however, no improvement in the thermal efficiency can be expected. Therefore, there is a lower limit to the amount of the preliminary air-fuel mixture which should be made to be burned by self-ignition.
That is, to improve the thermal efficiency while preventing knocking and production of a large amount of NOx, it is necessary to maintain the ratio of the preliminary air-fuel mixture burned by self-ignition in an optimum range and ensure that the preliminary air-fuel mixture burns successively by self-ignition with a time lag.
An object of the present invention is to provide a spark ignition type stratified charge combustion internal combustion engine causing part of the preliminary air-fuel mixture to burn by self-ignition and thereby improving the thermal efficiency, reducing torque fluctuation, and enabling a reduction in the amount of production of unburnt hydrocarbons.
According to the present invention, there is provided a spark ignition type stratified charge combustion internal combustion engine arranging a spark plug in a combustion chamber, said spark ignition type stratified charge combustion internal combustion engine forming by stratification a self-ignitable preliminary air-fuel mixture in the combustion chamber to give a spatial distribution to the density of the preliminary air-fuel mixture in the combustion chamber, igniting part of the preliminary air-fuel mixture formed in the combustion chamber by the spark plug to cause combustion by flame propagation, then successively making the remaining preliminary air-fuel mixture burn by self-ignition with a time lag, and setting the ignition timing so that the ratio of the preliminary air-fuel mixture made to burn by self-ignition becomes more than a predetermined lower limit and less than a knocking generation limit. | {
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The invention relates to an evaporation system for handling aqueous radioactive wastes. More specifically, the invention relates to a disposable evaporation system using standard 30 and 55 gallon drums as containment vessels for an adiabatic saturation process wherein moisture is absorbed by hot dry air moving through cascading spray and over standing liquid.
Recently, considerable interest has been generated in the handling of toxic nuclear waste materials. Certain commercial evaporation systems for reducing the volume of moderate quantities of low level nuclear wastes require personnel exposure to radioactive material during repair and servicing making such work difficult if not impossible. A disposable unit would require fewer handling operations; and consequently, less personnel exposure to radioactive material. Present commercial units are too large and expensive to be treated in a disposable manner. | {
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U.S. Pat. No. 6,298,824, incorporated by reference herein, discloses a control system for a fuel injected engine provides an engine control unit that receives signals from a throttle handle that is manually manipulated by an operator of a marine vessel. The engine control unit also measures engine speed and various other parameters, such as manifold absolute pressure, temperature, barometric pressure, and throttle position. The engine control unit controls the timing of fuel injectors and the injection system and also controls the position of a throttle plate. No direct connection is provided between a manually manipulated throttle handle and the throttle plate. All operating parameters are either calculated as a function of ambient conditions or determined by selecting parameters from matrices which allow the engine control unit to set the operating parameters as a function of engine speed and torque demand, as represented by the position of the throttle handle.
U.S. Pat. No. 6,322,404, incorporated by reference herein, discloses a Hall effect rotational position sensor is mounted on a pivotable member of a marine propulsion system and a rotatable portion of the rotational position sensor is attached to a drive structure of the marine propulsion system. Relative movement between the pivotable member, such as a gimbal ring, and the drive structure, such as the outboard drive portion of the marine propulsion system, cause relative movement between the rotatable and stationary portions of the rotational position sensor. As a result, signals can be provided which are representative of the angular position between the drive structure and the pivotable member.
U.S. Pat. No. 7,156,709, incorporated by reference herein, discloses the calibration procedure allows an upward maximum limit of tilt to be automatically determined and stored as an operator rotates a marine propulsion device relative to a marine vessel with a particular indication present. That indication can be a grounded circuit point which informs a microprocessor that at calibration procedure is occurring in relation to an upward trim limit. When the ground wire is removed or disconnected from the circuit point, the microprocessor knows that the calibration process is complete. During the rotation of the outboard motor or marine propulsion device in an upward direction, both the angular position of the outboard motor and the direction of change of a signal from a trim sensor are stored.
U.S. Pat. No. 7,416,456, incorporated by reference herein, discloses an automatic trim control system changes the trim angle of a marine propulsion device as a function of the speed of the marine vessel relative to the water in which it is operated. The changing of the trim angle occurs between first and second speed magnitudes which operate as minimum and maximum speed thresholds.
U.S. Pat. No. 8,762,022, incorporated by reference herein, discloses a system and method is provided for efficiently changing controlled engine speed of a marine internal combustion engine in a marine propulsion system for propelling a marine vessel. The system responds to the operator changing the operator-selected engine speed, from a first-selected engine speed to a second-selected engine speed, by predicting throttle position needed to provide the second-selected engine speed, and providing a feed forward signal moving the throttle to the predicted throttle position, without waiting for a slower responding PID controller and/or overshoot thereof, and concomitant instability or oscillation, and then uses the engine speed control system including any PID controller to maintain engine speed at the second-selected engine speed.
U.S. Pat. No. 8,011,982, incorporated by reference herein, discloses a support system for an outboard motor provides a restricted member that is attached to a bottom portion of the outboard motor and a restricting member that is attached to a support structure that is, in turn, attached to a transom of a marine vessel. The restricted member is prevented from moving in a starboard or port direction by a magnitude greater than a preselected magnitude that is defined by a gap between restricting and restricted surfaces that move into contact with each other when forces on the outboard motor cause a lower portion of the outboard motor to move by a magnitude greater than a predefined limit in either the port or starboard directions. Preselected gaps between restricting and restricted surfaces are sized to allow nominal vibration at low operating speeds of the outboard motor while restricting excessive lateral movement during operation at high speed.
U.S. Pat. No. 8,457,820, incorporated by reference herein, discloses a method is provided by controlling the operation of a marine vessel subject to porpoising. The method includes sensing an operational characteristic of the marine vessel which is indicative of porpoising of the marine vessel, and responding to the sensing of the operational characteristic with a response that is representative of the operational characteristic of the marine vessel as being indicative of the porpoising of the marine vessel.
Unpublished U.S. patent application Ser. No. 14/684,952, filed Apr. 13, 2015, and assigned to the Applicant of the present application, incorporated by reference herein, discloses a method for setting an engine speed of an internal combustion engine in a marine propulsion device to an engine speed setpoint includes receiving an operator demand from an input device and learning an adapted maximum engine speed. An engine speed setpoint is calculated by scaling the adapted maximum engine speed relative to the operator demand. The method includes predicting a position of a throttle valve of the engine that is needed to achieve the engine speed setpoint, and determining a feed forward signal that will move the throttle valve to the predicted position. A marine propulsion system has an electronic control unit that learns the adapted maximum engine speed, calculates the engine speed setpoint by scaling the adapted maximum engine speed relative to the operator demand, predicts the position of the throttle valve, and determines the feed forward signal that will move the throttle valve to the predicted position.
Unpublished U.S. patent application Ser. No. 14/873,803, filed Oct. 2, 2015, and assigned to the Applicant of the present application, incorporated by reference herein, discloses systems and methods disclosed herein control position of a trimmable drive unit with respect to a marine vessel. A controller determines a target trim position as a function of vessel or engine speed. An actual trim position is measured and compared to the target trim position. The controller sends a control signal to a trim actuator to trim the drive unit toward the target trim position if the actual trim position is not equal to the target trim position and if at least one of the following is true: a defined dwell time has elapsed since a previous control signal was sent to the trim actuator to trim the drive unit; a given number of previous control signals has not been exceeded in an attempt to achieve the target trim position; and a difference between the target trim position and the actual trim position is outside of a given deadband.
Unpublished U.S. patent application Ser. No. 15/003,326, filed Jan. 21, 2016, and assigned to the Applicant of the present application, incorporated by reference herein, discloses a method for controlling a trim system on a marine vessel includes receiving an actual trim position of a trimmable marine device at a controller and determining a trim position error by comparing the actual trim position to a target trim position with the controller. The method also includes determining an acceleration rate of the marine vessel. In response to determining that the trim position error exceeds a first error threshold and the magnitude of the acceleration rate exceeds a given rate threshold, the controller commands the marine device to the target trim position. In response to determining that the trim position error exceeds the first error threshold and the acceleration rate does not exceed the given rate threshold, the controller commands the marine device to a setpoint trim position that is different from the target trim position. An associated system is also disclosed.
Unpublished U.S. patent application Ser. No. 15/003,335, filed Jan. 21, 2016, and assigned to the Applicant of the present application, which is incorporated by reference herein, discloses a method for controlling a trim system on a marine vessel includes receiving an actual trim position of a trimmable marine device at a controller and determining a magnitude of a trim position error by comparing the actual trim position to a target trim position with the controller. The method also includes determining a magnitude of an acceleration rate of the marine vessel. The controller determines the activation time of a trim actuator coupled to and rotating the marine device with respect to the marine vessel based on the magnitude of the trim position error and the magnitude of the acceleration rate. The controller then sends a control signal to activate the trim actuator to rotate the marine device toward the target trim position. The method includes discontinuing the control signal once the activation time expires to deactivate the trim actuator. A corresponding system is also disclosed. | {
"pile_set_name": "USPTO Backgrounds"
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In an imaging environment, such as an imaging or a photograph editing application (e.g., Adobe® Photoshop®), pixel colors or color adjustments are frequently determined using undefined pixels where some information associated with those pixels is not initially known. For instance, in some cases, certain images are incomplete and result in portions of the image that are unclear, missing, and/or otherwise lack information. By way of example, images received over a network or captured via a camera may degrade and lack information for all pixels of the image resulting in unclear, blurry and/or other incomplete images. These images include a number of undefined pixels where information for those respective pixels is not known and a number of defined pixels where information for those respective pixels is known.
In other cases, compositing images or pasting an image over a background can utilize initially undefined pixels that lack color difference information to blend or transition the pixel colors. By way of example, a user may desire to paste an image, or portion thereof (e.g., foreground image) over a background image. In such a case, color modifications may be made in association with pixels, such as foreground pixels, in an effort to blend the images. The color modifications can be determined using a number of undefined pixels where color difference information for those respective pixels is not known and a number of defined pixels where color difference information for those respective pixels is known.
In some instances, a system of linear equations may be used to mathematically derive the unknown information of the undefined pixels. The mathematically derived information may then be filled into the undefined pixels to complete the degraded image. Deriving and solving the system of linear equations can require significant computing resources and can require an excessive amount of time to solve for the undefined pixels.
Further, in conventional implementations used to derive color modification information for initially undefined pixels, the transition in color of pixels across a boundary between a foreground image pasted in association with a background image can be visually recognized, that is, the seam can be observed between the images. For example, the pixel modifications made from the border of the foreground image inward may change too quickly thereby inhibiting a smooth transition. Such an apparent transition between images is oftentimes an undesirable result as a seamless transition between the pasted region and the background image is desired by a user so that the resulting image appears unaltered. | {
"pile_set_name": "USPTO Backgrounds"
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Three-dimensional vertical NAND strings having one bit per cell are disclosed in an article by T. Endoh et al., titled “Novel Ultra High Density Memory With A Stacked-Surrounding Gate Transistor (S-SGT) Structured Cell”, IEDM Proc. (2001) 33-36. | {
"pile_set_name": "USPTO Backgrounds"
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This disclosure relates to systems and methods for joint resurfacing, replacement, and the like. While the examples in the present disclosure relate to the knee joint, the systems and methods are applicable to other synovial joints in the body.
Arthroplasty procedures seek to replace a natural joint that has deteriorated in its functionality, range of motion, weight bearing, and most, if not all, other performance and a lifestyle attributes. Joint resurfacing typically involves removal of at least a portion of a natural articular surface of a bone in order to replace the removed tissue with a prosthesis having an articular surface that replicates at least the removed portion of the natural articular surface. Joint replacement may involve more extensive bone removal and subsequent replacement with a more substantial prosthesis. In this disclosure, remarks about resurfacing are to be considered equally relevant to replacement, and vice versa.
Arthroplasty procedures may involve one or more articular surfaces of a joint. In the knee, for example, the medial femoral condyle, the lateral femoral condyle, the medial tibial condyle, the lateral tibial condyle, the trochlear groove, and/or the patella may be resurfaced or replaced. A procedure may be described as unicondylar if one condyle of the joint is treated, such as the medial tibial condyle. Bicondylar procedures may treat two condyles of a bone, such as the medial and lateral tibial condyles. A procedure may be described as unicompartmental if one compartment of the joint is treated, such as the medial compartment of the knee. Bicompartmental procedures may treat two compartments, such as the medial and lateral compartments of the knee. A procedure may be described as a total joint procedure if most or all opposing articular surfaces of the joint are resurfaced or replaced. A procedure may be described as a hemiarthroplasty procedure if the prosthetic component articulates against an opposing natural articular surface, such as the prosthetic medial tibial component articulating against the natural medial femoral condyle. | {
"pile_set_name": "USPTO Backgrounds"
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Described herein is a process for using amphiphilic compounds, such as cationic surfactants. This process involves combining sources of oxides with amphiphilic compounds and solvent under conditions where aggregates of these amphiphilic compounds form. The mesoporous oxide products produced by the process have certain structural characteristics observed for liquid crystals of the amphiphilic compounds. | {
"pile_set_name": "USPTO Backgrounds"
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In armed conflicts, land mines are a serious threat to people or vehicles traveling on the ground. In recent conflicts around the world, attacks from improvised explosive devices (IED) are becoming more common. IEDs may also include some form of armored penetrator, including explosively formed penetrators (EFP). Armored vehicles, such as the Mine Resistant Ambush Protected (MRAP) vehicle, have been designed to help withstand these attacks and minimize harm to the vehicle's occupants. | {
"pile_set_name": "USPTO Backgrounds"
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In the area of producing a sinusoidal control frequency of the above type it has been known to employ a control frequency generator which in its structure resembles a dynamo which is driven synchronously with respect to the running of the movie camera.
The last mentioned type control frequency generator requires a very high driving energy and also requires substantial space, thus consequently it will contribute to the cost of the apparatus. Such control frequency generators are, therefore, not practical for amateur movie cameras. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to optical communication equipment and, more specifically but not exclusively, to optical signal-transmission techniques.
2. Description of the Related Art
This section introduces aspects that may help facilitate a better understanding of the invention(s). Accordingly, the statements of this section are to be read in this light and are not to be understood as admissions about what is in the prior art or what is not in the prior art.
Optical fibers that are typically used in optical communication systems have a relatively low threshold for nonlinear optical effects. This characteristic of optical fibers becomes especially pronounced with wavelength-division-multiplexing (WDM) transmission formats, where many closely spaced wavelength channels populate the same optical fiber. As a result, the total light intensity in the fiber core becomes relatively high, which facilitates inter-channel nonlinear optical effects. As the modulation speed in each wavelength channel increases, the optical power needed for each channel tends to increase, which tends to promote intra-channel nonlinear optical effects in addition to the inter-channel effects.
One prior-art approach to dealing with adverse nonlinear effects in the optical fiber is to attempt to suppress all nonlinear effects by placing a relatively low limit on the optical power in the fiber. For example, a representative commercial 128-channel WDM system operating at a bit rate of 10 Gb/s per channel may limit the optical power to approximately −5 dBm/channel, for a total optical power of about 16 dBm. However, a relatively low channel power may result in a relatively low optical signal-to-noise ratio, which disadvantageously increases the bit-error rate (BER). The low optical signal-to-noise ratio may also limit the achievable spectral efficiency per channel and thus the total transmission capacity of the communication system. In addition, optical nonlinearities can be very useful for some applications, such as distributed in-fiber amplification, wavelength conversion, optical-pulse regeneration, dispersion compensation, and optical-signal monitoring. Hence, a more-balanced approach is needed that, on the one hand, enables mitigation of the adverse nonlinear effects and, on the other hand, takes advantage of the useful ones. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates generally to the field of bulk fluid container sensors and, more particularly, to an in-situ container sensor system and method for obtaining real-time temperature and pressure readings used in calculating the actual density of a liquid material in a container.
2. Technical Background
Container sensors are known in the art and typically include capacitance probes, float actuated electro-mechanical devices, hydrostatic (pressure), ultrasonic or manual sensors. These sensors usually provide only the height or level of the liquid material in a container, not the true density of that liquid material at known or various temperatures. Density determinations are in accurate because they are based upon assumptions as to the overall liquid material temperature, and stated specific gravity which may be inaccurate.
In addition to the minimum data acquisition provided by the current container sensors, it is well known that the use of these container sensors provide a safety concern as well. For example, when using a physical measurement system, an individual has to open a hatch on top of the container to use a physical measuring tool, which can not only have environmental concerns but also health and safety concerns. Sensors, such as strain, radar, or ultrasonic, to be used on the exterior of the container to measure the liquid weight or fluid height, e.g., volume of liquid remaining in the tank, appear to solve this concern, however, they only return a single measurement value. Once attached to the exterior of the container, these sensors are difficult to remove or calibrate. Moreover, in instances where two sensors may be used it is difficult to determine the separation distance between the sensors on the outside of the container, due to expansion and contraction of the assembly that holds the two sensors, a slight variation in the distance span between the two sensors could dramatically affect the accuracy of the temperature readings, and thus, the density calculations.
Further, real-time, in-situ density information cannot be provided when using these sensors. For instance, when using an acoustic system, pressure sensors are inserted in the container to measure the volumetric change as a function of the distance to the fluid surface. Thus, use of the current sensors provide no mechanism within which to determine two measurements that indicate actual fluid material inside the container, or the actual steady-state temperature of the material inside the container.
What is needed, therefore, and currently not available in the art, is a sensor that can be inserted into a container to provide real-time measurements of not only the differential pressure exerted by the level of a liquid in a container, but also the temperature of a liquid. In addition, once these measurements are obtained, what is needed is a method by which these measurements are used in the accurate real-time calculation of the density (e.g. specific gravity) of the liquid. Further, the sensor must not only be accurate and easy to use but also provide a means for determining whether leakage (loss of actual level) is occurring from within the container. Additionally, what is further needed is a method of transmitting the data obtained from the container sensor to a data management system to determine real-time density based on differential pressure measurements. It is to the provision of such a container sensor system and method that the present invention is primarily directed.
One aspect of the present invention is to provide a configuration for a container sensor which measures real-time temperature and differential pressure based on two known points in distance.
Another aspect of the present invention relates to a container sensor that can be inserted into the interior of a container to measure at more than one location, the temperature and pressure of the liquid contained therein.
Yet another aspect of the present invention relates to a container sensor that provides not only the height of the liquid in a container, but also the true density (converted to specific gravity) of that liquid based on actual temperature and extrapolated for any temperature.
Yet another aspect of the present invention is to provide a method of using the sensor to determine whether any leakage of the liquid in the container has occurred.
Another aspect of the present invention is to provide a safe and reliable means of measuring the temperature and pressures inside the liquid in a container.
Yet another aspect of the present invention is to provide a method of transmitting the data obtained from the container sensor to a data management system to determine real-time density measurements.
Yet a further aspect of the present invention is to provide a sensor or sensing array that can be easily inserted into the container regardless of the fluid chemistry.
The container sensor invention as disclosed and taught here provides a number of advantages over other container sensors known in the art. For example, having in-situ readings of the temperature and pressure of the liquid inside the container provides greater reliability and accuracy of that data. Since the temperature readings are taken inside the container, the exact liquid pressure (differential pressure between two absolute reference points within the array) and temperature can be determined from the sensors and thus, provide for a more accurate density calculation. In addition, since the container sensor can make several real-time readings of the temperature and pressure at different levels within the liquid, these readings can be used together to determine a more accurate reading. By using the container sensor, one is able to determine whether any leaks exist inside a container, and if so, the flow-rate of those leaks. The container sensor can easily be inserted through a small pipe opening in the container, rather than opening a hatch on top of the container.
These and additional features and advantages of the invention will be set forth in the detailed description which follows, and in part will be readily apparent to those skilled in the art from that description or recognized by practicing the invention as described herein. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a system and a method for communication using an IP (Internet Protocol), and more particularly to a system and a method for communicating by using different IPs according to a specific service by a UE.
2. Description of the Related Art
As generally known in the art, an IP refers to an Internet layer protocol devised to provide wired communication devices with various types of packet services. Development of IP communication technology is followed by discussion of schemes for allocating an IP to a UE to support a packet service in a mobile communication system.
An IP allocated to a UE is maintained the same in a subnet managed by a gateway that has allocated the IP. However, if the UE moves or if the gateway is changed by a specific communication situation, a new IP is generally allocated to the UE by a new gateway. Then, the service that has been provided through the previous IP is interrupted or terminated.
In other words, use of a fixed IP has a problem in that the continuity of the service provided to the UE is not generally guaranteed if the UE moves or if the communication situation of the UE varies.
This will be explained with reference to an example. It is assumed that a UE supports a VoIP (Voice of Internet Protocol) service by using an IP. The UE supports voice communication with another UE by using an allocated IP. If the user moves (e.g. by mass transportation, by car, or on foot), the gateway of the IP allocated to the UE may move out of the area under management. In this case, the UE is assigned a new IP from a new gateway. This means, in this situation, the UE cannot support the VoIP service any more by using the previously allocated IP.
As a result, the voice communication between both UEs is interrupted, and the UE must dial again, i.e., the voice communication-related call setup signaling must resume from the beginning.
In an attempt to solve the above-mentioned problem, a mobile IP has been proposed. According to this scheme, a UE is assigned two IPs, i.e. a fixed IP that remains unchanged regardless of mobility of the UE, and a mobile IP that varies as the UE moves. The fixed IP is referred to as a HA (Home Address), which is made known to the outside when the UE is to use a service. The mobile IP is referred to as a CoA (Care of Address).
When the mobile IP is applied to a UE supporting the VoIP service, the UE has a HA and a CoA. If the UE moves, the CoA is varied, but the HoA is retained, so that the voice communication service is maintained continuously.
As explained above, a specific service in a communication system must have its continuity guaranteed, considering the service characteristics. This is crucial for satisfying the demand of service users. The specific service includes, for example, a VoIP service, a FTP (File Transfer Protocol) service, a streaming service, etc.
The service continuity is becoming a major issue in the next-generation mobile communication system, and the mobile IP needs to be adopted in connection with support for the service continuity. This necessitates discussion of a detailed method regarding how and which IP is to be used for communication in connection with service continuity in the next-generation mobile communication system. | {
"pile_set_name": "USPTO Backgrounds"
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Conventionally pneumatic rubber vehicle tires are produced by molding and curing a green or uncured and unshaped tire in a molding press. The green tire is pressed outwardly against a mold surface by means of an inner fluid-expandable bladder. By this method the green tire is shaped against the outer mold surface which defines the tire tread pattern and configuration of the sidewalls. By application of heat and pressure the tire is molded and cured at elevated temperatures.
In general practice, the expansion of the bladder is accomplished by application of internal pressure to the inner bladder cavity which is provided by a fluid such as gas, hot water and/or steam which also participates in the transfer of heat for the curing or vulcanization of the tire. The tire is then conventionally allowed to cool somewhat in the mold, sometimes aided by adding cold or cooler water to the bladder. Then the mold is opened, the bladder is collapsed by removal of its internal fluid pressure and the tire is removed from the tire mold. Such use of tire curing bladders is well known to those having skill in the art.
It is recognized that there is substantial relative movement between the outer contacting surface of the bladder and the inner surface of the tire during the expansion phase of the bladder. Likewise, there is considerable relative movement between the outer contacting surface of the bladder and the cured inner surface of tire during the collapse and the stripping of the bladder from the tire after the tire has been molded and vulcanized.
The bladder surface can tend to stick to a tire's inner surface after the tire is cured and during the bladder collapsing part of the tire cure cycle. This adhesion may cause roughening of the bladder surface if it is not controlled. This reduces bladder durability and can produce defective tires. For this reason, it is conventional practice to precoat the bladder and/or the inner surface of the green or uncured tires with a lubricant in order to provide lubricity between the outer bladder surface and inner tire surfaces during the entire molding operation. This lubricant has also been called a bladder lubricant, and is often a silicone polymer dispersed in a solvent or water.
It is to be appreciated that the release of the tire from its cure bladder in an industrial manufacturing setting is intimately associated with both the phenomenon of release (to prevent sticking) and the phenomenon of lubrication (to enhance slipping) between the bladder and the adjacent tire surfaces. The release aspect refers to the basic ability to avoid adhesion, or release and the aspect of lubrication relates to enhancing the ability of the surfaces to slip and enable a movement of the bladder with respect to the tire.
Butyl rubber is commonly used in tire curing bladders. Butyl rubber is a copolymer of predominantly isobutylene with small amounts of diene monomers usually isoprene to give sufficient unsaturation to allow the butyl rubber to be crosslinked. Copolymers of isobutylene and para-methylstyrene which are subsequently brominated are being manufactured by Exxon. These copolymers of isobutylene and para-methylstyrene are useful in applications where butyl rubber is used.
Fluorinated ethylene polymers have been added to thermoplastic and thermoset polymers in patents such as U.S. Pat. No. 3,002,938 where it was added at concentrations from 0.75 to 2.5 weight percent to provide ozone resistance; U.S. Pat. No. 3,600,309 where poly(tetrafluoroethylene) was added at concentrations from 0.05 to 0.45 parts per 100 parts rubber to solve extrusion related problems; U.S. Pat. No. 3,940,455 where oriented Teflon.TM. fibers were formed within an elastomer to enhance the apparent tensile strength; and U.S. Pat. No. 5,238,991 where poly(tetrafluoroethylene) and/or poly(fluoroethylene) compatibilizer was used in a tire side wall to enhance ozone resistance. The examples therein showed that ozone resistance is decreased in dynamic ozone tests when 10 parts poly(tetrafluoroethylene) per 100 parts rubber was used without a compatibilizer. The use of a compatibilizer allowed the use of larger amounts of poly(tetrafluoroethylene) in the composition.
U.S. Pat. No. 4,863,650 disclose the use of fillers such as kaolin, chalk, rock dust, silicas, carbon black and graphite in silicone release agent films to result in mat finishes. U.S. Pat. No. 4,310,427 disclosed the use of dry powders such as mica, talc, and graphite which were dusted onto the interior surfaces of "green" tires to provide lubrication and release. U.S. Pat. No. 3,967,978 disclosed the use of fine solid particles such as mica or graphite in the lubricant.
Phenolic resin curatives are accelerated (i.e. the curing rate is accelerated) by trace amounts of halogens typically added as a halogen containing rubber or attached to the phenolic resin. In the past the use of brominated phenolic resins such as Schenectady International's (Schenectady, N.Y.) SP1055 or 1056 in butyl rubber bladder compositions resulted in sticky compositions which adhered to the mixing equipment (e.g. Banbury.TM.). Thus, the advantages of the faster cure rates of SP-1055 and 1056 were not available for butyl bladder applications. Further conventional processing aids for rubber compositions were not effective in solving the adherence problem.
Accordingly, it is desired to provide a faster curing rate (e.g. more bladders produced per mold) and curing bladders with increased lubricity, decreased adhesion of the bladder to cured tires, increased flex life, and improved heat stability. | {
"pile_set_name": "USPTO Backgrounds"
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Air separation by rectification (at cryogenic temperatures) is well known. Typically, in such methods the air is separated in a double rectification column comprising a higher pressure rectification column, a lower pressure rectification column and a condenser-reboiler placing the higher pressure rectification column in heat exchange relationship with the lower pressure rectification column. Such an arrangement enables an oxygen product to be withdrawn from a bottom region of the lower pressure rectification column. In addition, a nitrogen product is typically taken from the top of the lower pressure rectification column.
Normally, a relatively high yield or recovery of oxygen from the incoming air can be achieved by rectification of the air in a double rectification column. However, various demands may be placed on the separation such that the oxygen recovery will fall. Such demands include the production of liquid products in an amount in excess of 5% of the total oxygen production when refrigeration of the process is provided by turboexpansion of air into the lower pressure rectification column; a requirement for a liquid nitrogen product; and a requirement for a gaseous nitrogen product not only from the lower pressure rectification column but also from the higher pressure rectification column. The demands on the separation process are increased if an argon product is formed by withdrawing an oxygen stream containing argon from the lower pressure rectification column and separating argon from it in a side rectification column. Further, if an argon product is produced, co-production of a nitrogen product from the higher pressure rectification column or co-production of relatively large proportions of liquid products can have a drastic effect on the argon recovery.
U.S. Pat. No. 5,469,710 relates to an air separation method employing a double rectification column and a side column in which an argon product is produced, wherein oxygen-enriched liquid is taken from the bottom of the higher pressure rectification column, is passed through a throttling valve into a condenser in which argon is condensed, the oxygen-enriched liquid thereby being vaporised, and a stream of the resulting vapour is expanded with the performance of external work and introduced into the lower pressure rectification column. Such an arrangement is advantageous in that it is a useful way of providing additional refrigeration for the separation, thereby adding to the flexibility of the method in being able to provide liquid products without unacceptable product recoveries or unacceptable power consumption. The method is, however, limited by the fact that the argon condenser needs to be operated at a pressure less than 2 bar in order to provide the necessary temperature difference for the condensation of argon; therefore the amount of refrigeration that can be produced by expansion to the pressure of the lower pressure rectification column is strictly limited.
It is an aim of the present invention to provide a method and apparatus which enables oxygen recovery, and, if separated, argon recovery to be enhanced. | {
"pile_set_name": "USPTO Backgrounds"
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In a conventional suspension system, a road wheel is mounted for movement upwardly and downwardly relative to the body. A coil spring and a shock absorber are typically arranged between the body and the supporting structure on which the wheel is mounted. The shock absorber controls the flow of fluid between two chambers, and functions to dampen the velocity of relative movement between the body and the road wheel.
In recent years, there has been considerable interest in developing an "active" vehicle suspension system. See, e.g.: "Lotus' active suspension", Automotive Engineer (Febrary/March 1984) [pp. 56-57]; McCosh, "no-springs, no-shocks suspension", Popular Science (July 1986) [pp. 60-63]; and McCosh, "Springless Corvettes", Popular Science (Sept. 1986) [p.12]. In these "active" systems, the conventional spring and shock absorber are replaced by a servocontrolled double-acting hydraulic actuator. Suitable sensors, such as accelerometers and the like, are used to sense and determine certain parameters, such as body attitude and acceleration. The signals generated by these sensors are appropriately tailored and used as command signals to servovalves, which control the flow of fluid to the actuators. Thus, rather than merely responding passively and reactively to various forces acting on the vehicle, the "active" systems may be used to affirmatively correct and compensate for the effects of such forces. For example, during braking, the conventional vehicle will "nose down". However, with an actively-controlled system, the various servos may be operated, either independently or in combination with one another, to maintain the body level and horizontal during braking, acceleration and cornering.
In some hybrid or semi-"active" systems, the conventional spring remains, but the shock absorber is replaced by a servocontrolled actuator. Such spring and actuator may be arranged either in parallel or in series with one another.
In any event, in such "active" and "semi-active" systems, and in still other level- and attitude-control systems (e.g., those employing variable-rate shock absorbers having fluid damping characteristics which vary with position), it is often desired to known the relative positions between the wheel and body. Such data may, for example, be used as a feedback signal in a closed-loop servocontrol system. There are many devices available for sensing position and converting it into an analog electrical signal. One such device is a linear variable differential transformer (LVDT), which has a core movable relative to a sensing coil. Such devices could, of course, be connected directrly to the body and the wheel. However, the typical stroke of relative movement between the wheel and the body is relatively long, and this would require the use of a correspondingly long-stroke LVDT. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to managing taxonomic information.
With modern advances in computer technology and network and Internet technologies, vast amounts of information have become readily available in homes, businesses, and educational and government institutions throughout the world. Indeed, many businesses, individuals, and institutions rely on computer-accessible information on a daily basis. This global popularity has further increased the demand for even greater amounts of computer-accessible information. However, as the total amount of accessible information increases, the ability to locate specific items of information within the totality becomes increasingly more difficult.
The format with which the accessible information is arranged also affects the level of difficulty in locating specific items of information within the totality. For example, searching through vast amounts of information arranged in a free-form format can be substantially more difficult and time consuming than searching through information arranged in a pre-defined order, such as by topic, date, category, or the like. Due to the nature of certain on-line systems much of the accessible information is placed on-line in the form of free-format text. Moreover, the amount of on-line data in the form of free-format text continues to grow very rapidly.
Search schemes employed to locate specific items of information among the on-line information content typically depend upon the presence or absence of key words (words included in the user-entered query) in the searchable text. Such search schemes identify those textual information items that include (or omit) the key words. However, in systems, such as the World Wide Web (“Web”), or large Intranets, where the total information content is relatively large and free-form, key word searching can be problematic, for example, resulting in the identification of numerous text items that contain (or omit) the selected key words, but which are not relevant to the actual subject matter to which the user intended to direct the search.
As text repositories grow in number and size and global connectivity improves, there is a need to support efficient and effective information retrieval (IR), searching, and filtering. A manifestation of this need is the proliferation of commercial text search engines that crawl and index the Web, and subscription-based information mechanisms.
Common practices for managing such information complexity on the Internet or in database structures typically involve tree-structured hierarchical indices such as the Internet directory Yahoo!™, which is largely manually organized in preset hierarchies. Patent databases are organized by the U.S. patent office's class codes, which form a preset hierarchy. Digital libraries that mimic hardcopy libraries support subject indexing inspired by the Library of Congress Catalogue, which is also hierarchical.
Querying or filtering by key words alone can produce unsatisfactory results, since there may be many aspects to, and often different interpretations of, the key words, and many of these aspects and interpretations may be irrelevant to the subject matter that the searcher intended to find.
For example, if a wildlife researcher is attempting to find information about the running speed of the jaguar by submitting the query “jaguar speed” to an Internet search engine, a variety of responses may be generated, including responses relating to Jaguar® cars and a Jaguar sports team, as well as responses relating to the jaguar animal.
If an index such as Yahoo!™ is used, the user can seek documents containing “jaguar” in the topical context of animals. It is labor- and time-intensive to maintain such an index as the Web changes and grows.
Biocentric information is information associated with at least one instance of something that is or was alive (“biotic entity” or “organism”), and, as illustrated in FIGS. 1-2, may include human observations recorded to physical media, physical specimens, and other biocentric data items that libraries store and that museums collect, including photographs, slides, and annotations on physical specimens. Libraries house vast collections of publications, many of which refer to the observations and recordings about the natural world (see, e.g., FIG. 3).
As shown by example in FIG. 4, biocentric data items can be electronic objects that represent biocentric information in an electronically accessible way. Biocentric data items can be derived from biocentric information in a variety of formats.
Biocentric files may be served through applications, as illustrated by examples in FIG. 5. Observations may be recorded in tables that are served via database management tools. A suite of software tools may allow table data to be flexibly delivered to the Web. Accordingly, information on specimen collections, bibliographic references, and field observations of organisms can be recorded and retrieved.
Multimedia objects having audio, illustrations, photographs, or video (sometimes referred to as “binary large objects” or “BLOBs”) may be served by many applications. FIG. 6 illustrates an example of a combination of database and image server used to serve photos to the Web. The images are served through the image data server, which communicates with the database server to locate and serve the associated text annotations.
Full-text documents represent a resource of biocentric information. Books, journals, monographs, and manuscripts are historic means of communicating and storing knowledge of the natural world. The recording, parsing, and serving of full-text is a complicated endeavor. Technologies known as Standard Generalized Markup Language (SGML) and Extensible Markup Language (XML) offer a flexible infrastructure for serving full-text data, as diagrammed in FIG. 7.
Applications reside on host computers that serve that biocentric data through network protocols. Often these hosts are specialized for a particular task or group of tasks, as illustrated by examples in FIG. 8. One server may supply many different services or the services may reside on more than one machine. The information that is served may reside at a particular location to take advantage of services on the host or proximity to a data manager to facilitate management.
Multiple hosts can be organized within logical subnetworks that can be viewed as a logical entity known as a domain, as shown by example in FIG. 9. A domain may represent a collection of hosts, each with its own collection of applications, each with its own collection of biocentric data.
FIG. 10 illustrates by example that relationships exist between domains and applications within domains concerning the biocentric data. A domain is a user-defined arbitrary collection of applications. For example, an institution may have a library catalog application and an on-line encyclopedia application, both of which rely on animal names.
Scientific interest in the creation of a unified catalog of the 1.75 million known species of living organisms has been recognized by Species 2000 and North America's Integrated Taxonomic Information Systems (ITIS).
Such an attempt to organize biocentric information is put forth in the context of the large number of species, the variation within species, and the expression of individual and species information with historical and geographical dimensions, from scales ranging from the molecular to the ecosystem, and modified as a function of a myriad of potential biotic and abiotic interactions. Furthermore, much of the known information was collected in a pre-electronic format, and the ranks of the custodians of much of that information (primarily taxonomists) are not being fully replenished as the custodians retire. Bioinformatics tools such as GenBank® are available to deal with molecular data. However, data on biodiversity can be difficult to assemble. The challenge of making biodiversity information available electronically is of such a magnitude that it has been described as requiring a “mega science” response. Federal and intergovernmental programs such as Global Biodiversity Information Facility (GBIF), Partnerships for Enhancing Expertise in Taxonomy (PEET), Australian Biological Resources Study (ABRS), and Species 2000 have emerged to address this problem. One strategy is based on assembling large databases.
Facilities that have been proposed include the following. A GBIF connects smaller databases and creates a directory of the three billion specimens in museums and seed banks. GBIF is an initiative of the United Nations Environment Programme/Organization for Economic Cooperation and Development (UNEP/OECD) and inter-governmental programs committed to documenting the diversity of life. GBIF includes Species 2000 and the Expert Taxonomy Institute (ETI) as associates.
Species Analyst is a biodiversity site that provides access to natural-history databases to promote taxonomy in the United States. Species Analyst seeks to integrate biodiversity information through the Web.
Species 2000, which aims to index all the world's known species, has data on 250,000 species in a rigid database structure. Species 2000 is a focal point for many biodiversity enterprises.
Deep Green presents data on the genetics and evolution of plants. | {
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The present invention relates generally to a turbo-code decoding apparatus and method. In particular, the invention relates to an improved turbo-code decoding apparatus and method for decoding a convolution encoded data frame using symbol-by-symbol trace back and an approximation into HR-SOVA to improve bit error rate (BER) performance with fewer iterations.
In 1948 Shannon published a paper entitled xe2x80x9cA Mathematical Theory of Communicationxe2x80x9d in the Bell System Technical Journal, Vol. 27, pp. 379-423 and pp. 623-656, 1948. Shannon showed that the system capacity, C, of a channel perturbed by additive white Gaussian noise power (AWGN) is a function of the average received signal power, S, the average noise power, N, and the bandwidth, W. The system capacity is given by the following formula:
C=W log2(1+S/N)
This equation promises the existence of error correction codes that enable information transmission over a noisy channel at any rate, R, where Rxe2x89xa6C, with an arbitrarily small error probability. Shannon""s work showed that the values of S, N, and W, set a limit on the transmission rate, not on the error probability.
In a subsequent paper entitled xe2x80x9cCommunication Theory of Secrecy Systems,xe2x80x9d Bell System Technical Journal, Vol. 28, pp. 656-715, 1949, Shannon showed that the maximum amount of information that can be transmitted over a noisy channel is limited by the following formula, known as the Shannon limit:
Eb/N0=W/C(2C/Wxe2x88x921)=xe2x88x921.59 db
where Eb represents the bit energy of the transmitted information bits; N0 represents a proportionality constant of the noise power N, such that N0=N/W; and Eb/N0 is the signal to noise ratio.
Shannon""s work established the benchmark by which the performance of all error control coding techniques, in terms of bit error rate (BER), are measured. However, it was not until the discovery of a new class of convolution codes that the BER of an error control coding technique came close to the Shannon limit. In the paper C. Berror, A. Glavieux, and P. Thitimajshima, xe2x80x9cNear the Shannon Limit Error-Correcting Coding and Decoding: Turbo-Codes(1),xe2x80x9d in Proc., IEEE Int. Conf. on Communications (Geneva, Switzerland, May 1993), p. 1064-1070, such a Turbo-Code encoder is described. The Turbo Code encoder, built using a parallel concatenation of two Recursive Systematic Convolution Codes (RSC) and the associated decoder, using a feedback decoding rule, is implemented as P pipelined identical elementary decoders. Simulation results of the Turbo-Code decoder achieved a Eb/N0=0.7 dB. However the hardware implementation of the decoder required a huge interleaver of 64,500 bits, 18 iterations to decode each symbol, and some ad hoc fine tuning factors of the updating rule.
In Joachim Hagenauer, Elke Offer, and Lutz Papke, xe2x80x9cIterative Decoding of Binary Block and Convolutional Codes,xe2x80x9d IEEE Trans. on Information Theory, 42(2):429-445, 1996, (Hagenauer et al) a decoder is described that accepts soft inputsxe2x80x94including a priori valuesxe2x80x94and delivers soft outputs that can be split into three terms: the soft channel, and a priori inputs, and the extrinsic value. The extrinsic value is used as an a priori value for the next iteration. The iterations are controlled by a stop criterion derived from cross entropy, which results in a minimal number of iterations. The decoder applies a soft output Viterbi algorithm (SOVA) to decode turbo codes. SOVA modifies the conventional Viterbi algorithm to generate soft decisions, rather than hard decisions (0/1), based on the updating rule described in Hagenauer et al. Details regarding the Viterbi algorithm are described in xe2x80x9cError control systems for digital communication and storagexe2x80x9d by Stephen B. Wicker published 1995 by Prentice Hall, Inc., Englewood Cliffs, N.J. 07632, ISBN 0-13-200 809-2.
Hagenauer""s updating rule (typically called the HR rule) is a low complexity approximation algorithm for turbo decoding. Its lower complexity makes it suitable for hardware implementation. However the HR rule still requires significant resources of memory when an entire block or frame of data has to be processed with a single traceback step. In addition, an HR-SOVA decoder using the HR rule is sub-optimal due to the fact that the a priori or confidence value grows very rapidly (too rapidly) following each iteration. The HR rule erroneously overestimates the confidence value and thereby eliminates the opportunities to recognize and correct bit errors.
In Lang Lin and Roger S. Cheng, xe2x80x9cImprovements in SOVA-Based Decoding for Turbo Codes,xe2x80x9d In Proceedings of the ICC, 1997 (Lang et al), the authors proposed a modification to the HR-SOVA decoder to thereby limit the reliability/confidence values to a small range to compensate for the defect brought by overestimating those values in the original SOVA. However, it is unclear whether this fixed saturation technique creates an upper bound for an extrinsic likelihood value generated from the modified confidence values.
What is needed is an improved Turbo-code decoder that results in Bit Error Rate (BER) performance comparable to full-length traceback BER performance even when using small, fixed-length traceback (symbol-by-symbol traceback). A need also exists for a Turbo-code decoder that results in a steeper convergence in the initial few iterations, thereby allowing the use of fewer iterations for the same BER performance. Consequently, the use of fewer iterations reduces the time required for computing a result. A need also exists for a Turbo-code decoder that results in lower power consumption or can allow higher data rates to be processed at the same clock speeds when compared to fixed-saturation or non-saturation techniques. The technique must be robust enough to sustain a loss of the least significant bit (LSB) of the likelihood values without deterioration in BER performance to reduces storage requirements.
The present invention overcomes the problems associated with the prior art systems by disclosing a method and apparatus that (a) improves the Bit Error Rate (BER) performance of a priori SOVA (APRI-SOVA) based on the updating rule as described in Hagenauer et al (henceforth referred to as HR-SOVA); (b) does so in fewer iterations, hence impacting favorably on computational requirements; and (c) remains very suited for hardware implementation. The present invention introduces an approximation into delta and likelihood values produced by a decoder utilizing the HR-SOVA algorithm in the form of two new saturation algorithms resulting in an improved Turbo code decoder.
One embodiment of the present invention is an apparatus which includes a first SOVA decoder that generates a first path reliability value from a channel value and a parity symbol of the encoded frame, and a first a priori likelihood value. A first decorrelation unit then generates a first extrinsic symbol reliability value by decorrelating the channel value and the first a priori likelihood value from the first path reliability value. A first symbol reliability saturation unit saturates the first extrinsic symbol reliability value to generate a first saturated extrinsic symbol reliability value. A first interleaver interleaves the first saturated extrinsic symbol reliability value to generate a second a priori likelihood value for a second stage of the decoder. A second interleaver interleaves the channel value to generate an interleaved channel value for the second stage of the decoder. A second SOVA decoder then generates a second path reliability value from an interleaved parity symbol of the encoded frame, the second a priori likelihood value, and the interleaved channel value. A second decorrelation unit generates a second extrinsic symbol reliability value by decorrelating the interleaved channel value and the second a priori likelihood value from the second path reliability value. A second symbol reliability saturation unit saturates the second extrinsic symbol reliability value to generate a second saturated extrinsic symbol reliability value. A first de-interleaver de-interleaves the second saturated extrinsic symbol reliability value to generate the first a priori likelihood value as an input to the first SOVA decoder. The decoder is completed by a second de-interleaver that de-interleaves the second extrinsic symbol reliability value to generate a decoded message of the convolution encoded data frame.
In a further embodiment, the apparatus further includes a first path reliability saturation unit that saturates the first path reliability value received from the first SOVA decoder to generate a first saturated path reliability value as an input to the first decorrelation unit. A second path reliability saturation unit saturates the second path reliability value received from the second SOVA decoder to generate a second saturated path reliability value as an input to the second decorrelation unit and the second de-interleaver. Moreover, the saturation technique of the present invention is sufficiently robust to sustain the loss of the LSB of the first and second a priori likelihood values in the interleaver memories.
Advantages of the invention include ease of hardware implementation. Moreover, hardware implementations employing the saturation technique of the present invention benefit by having improved BER characteristics. Furthermore this saturation technique results in faster convergence, thereby requiring fewer decoding iterations to generate a result as compared to fixed-saturation techniques and non-saturating techniques. This can help reduce the power consumption or handle higher data rates as necessary. Compared to non-saturating schemes, the saturation technique of the present invention requires a smaller word size for the first and second extrinsic symbol reliability values, resulting in a reduced memory sizes for the interleaver memories. | {
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Technical Field
The present disclosure relates to electronic devices on flexible substrates. The present disclosure relates more particularly to the field of wearable electronic devices on thin flexible substrates.
Description of the Related Art
There is increasing demand for electronic devices on flexible substrates. Electronic devices which can be worn on a person's clothing in particular are implemented on flexible substrates. Typically, these flexible substrates are at least 50 μm thick. One reason for this is that high temperature processing is often required for the fabrication of devices such as amorphous silicon thin film transistors, organic materials, CMOS devices, Memristors, thin film memories, precision thin film resistors, gas sensors, temperature sensors, thin film batteries, etc.
The maximum deposition temperature is based in part on the type of flexible substrate used. For example, many kinds of flexible substrates have maximum temperature allowances of 250° C. or below. If the maximum temperature is exceeded during processing, there will be deterioration of the properties of the substrate. This deterioration can include change in curvature, shape, or other deformation. | {
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The present invention relates to a high-pressure discharge lamp lighting apparatus system and, more particularly, to a high-pressure discharge lamp lighting apparatus system including a lighting apparatus for lighting a high-pressure discharge lamp such as a headlight of a vehicle, a high-pressure discharge lamp lighting apparatus, a lighting unit comprising the high-pressure discharge lamp lighting apparatus, and a vehicle in which the lighting unit is loaded.
In a conventional lighting apparatus used as a headlight of a vehicle to light a high-pressure discharge lamp, for example, luminous flux emitted from the high-pressure discharge lamp is made to rise quickly by supplying overcurrent to the high-pressure discharge lamp in a period immediately after the start of lighting until the lamp voltage rises adequately.
In addition, the conventional high-pressure discharge lamp lighting apparatus is constituted to supply a constant power to the high-pressure discharge lamp, in order to reduce the variation of the luminous flux emitted from the high-pressure discharge lamp in accordance with the irregularity in the characteristics or the characteristic variation based on the lifetime and the like in the high-pressure discharge lamp, in a stable state.
Incidentally, in the high-pressure discharge lamp of this kind, when turning on and turning off are repeated, its temperature variation causes the vapor pressure of a luminescent metal sealed therein to be varied and thereby the characteristics are varied.
For this reason, in the high-pressure discharge lamp for a headlight of a vehicle as described in, for example, Jpn. Pat. Appln. KOKAI Publication No. 10-41075 (prior art), the power to be supplied to the lamp is controlled in accordance with a state of a cold lamp (a cold state) or a state of a hot lamp (a hot state).
As shown in FIG. 6, a high-pressure discharge lamp lighting apparatus 40 of the prior art comprises a lighting control circuit 41, a charging/discharging circuit 42 that is a series circuit constituted by a resistor R and a capacitor C, a stable lighting discrimination circuit 43, a power supply resetting circuit 44 and a level resetting circuit 45.
The charging/discharging circuit 42 constitutes a time measurement circuit for measuring the ON/OFF time of the power supply.
The lighting control circuit 41 adjusts the power to be supplied to a lamp (not shown) by a lighting circuit (not shown) on the basis of a value of terminal voltage Vc of the capacitor C.
The stable lighting discrimination circuit 43 discriminates whether the lamp is in the hot state or not. When the terminal voltage Vc is higher than the discrimination reference value, i.e. when the lamp is in the hot state, the stable lighting discrimination circuit 43 outputs stable lighting discrimination signal Ss that is to be at high level to the level resetting circuit 45.
The power supply resetting circuit 44 operates the lighting control circuit 41 if a predetermined resetting period has passed, when the power supply is turned on.
The level resetting circuit 45 charges the capacitor C during the resetting period when the stable lighting discrimination signal Ss is at high level.
That is, when the power supply is turned on (or when the lamp is lit up again), if the lamp is in the hot state, the capacitor C is charged and the lighting control circuit 41 restricts the power to be supplied to the lamp on the basis of the terminal voltage Vc of the capacitor C, during a predetermined resetting period.
The high-pressure discharge lamp lighting apparatus 40 of the above-described prior art can restrict the supply of the power in quantities more than necessary ones to the lamp when turning on and off the power supply (or turning on and off the lamp) is repeated in a short time, after the high-pressure discharge lamp has been in the stable state.
However, the discrimination reference value is used to discriminate whether the lamp is in the hot state or not, and the power to be supplied to the lamp at the voltage near the terminal voltage Vc is varied in stages.
If the terminal voltage Vc of the capacitor C is higher than the discrimination reference value, the capacitor C is charged during a predetermined resetting period even when the value of the terminal voltage Vc is a value near the discrimination reference value or a value at which the capacitor C is fully charged, and therefore the power to be supplied to the lamp is substantially the same, which means the power in the stable state.
On the other hand, if the terminal voltage Vc of the capacitor C is lower than the discrimination reference value, the overvoltage is supplied to the lamp even when the value of the terminal voltage Vc is near the discrimination reference value at which the lamp is in the hot state.
As described above, the high-pressure discharge lamp lighting apparatus 40 has the drawback that the power supplied to the lamp is varied in stages with reference to the discrimination reference value and thereby an optimal power responding to the lamp temperature cannot be supplied. | {
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The present invention relates to grain-oriented silicon steel sheets having an easy magnetization axis <100> in the rolling direction of the steel sheets and <110> on the sheet surface.
Grain-oriented silicon steel sheets have been mainly used for iron core of electric apparatus, such as converter and the like as soft magnetic materials and in particular, it has been recently strongly demanded to increase the properties of the electric apparatus and the like, to make the size of said apparatus small and to make the noise lower and the electric steel sheets having more improved magnetic properties have been demanded in view of energy saving.
The magnetic properties of steel sheets are generally evaluated by both iron loss property and magnetization property. The improvement of magnetizing property (represented by the magnetic induction B.sub.10 value at a magnetizing force 1000 A/m) is particularly effective for increasing the designed magnetic induction and making the size of apparatus smaller. On the other hand, the improvement of the iron loss property (represented by iron loss W.sub.17/50 per 1 kg when being magnetized to 1.7T (Wb/m.sup.2) with 50 Hz) reduces the loss of heat energy when used as the electric apparatus and is effective in view of saving of consumed electric power. Since not only the magnetizing property but also the iron loss property can be improved by enhancing the orienting property of the products, that is by highly aligning the axis <100> of the crystal grains to the rolling direction, many investigations have been made particularly in this view and the products having B.sub.10 of more than 1.90T have been produced.
As well known, the iron loss is roughly classified into hysteresis loss and eddy current loss. As the physical factors influencing upon these losses, there are the purity and inner strain of the material other than the above described crystal orientation with respect to the hysteresis loss and there are the electric resistance (for example Si amount), sheet thickness and magnetic zone size (crystal grain size) of the steel sheet and the tension applied on the steel sheet with respect the eddy current loss. In usual grain-oriented silicon steel sheets, the eddy current loss is more than 3/4 of the total loss, so that it is more effective for reducing the total iron loss to reduce the eddy current loss than to reduce the hysteresis loss. Therefore, various attempts for reducing the eddy current loss have been made. As one of them, it has been proposed to increase Si content but when Si content is increased to 4.0%, the cold rolling ability is noticeably deteriorated, so that there is a limitation and such a means is not practical. As a means for applying tension on a steel sheet, a means utilizing a difference of thermal expansion coefficient between a base coating or a face coating and a base iron has been known but there is limitation in the tension obtained from the commercially utilized coating and there is also limitation in view of the uniformity, cohesion, appearance of the coating and the like and it is impossible to expect the satisfactory reduction of iron loss. It has been recently proposed to form scratches in perpendicular direction to the rolling direction on the surface of the produced sheet to make the magnetic zones fine whereby the eddy current loss is reduced. But, in this method, the effect may not be necessarily fully developed depending upon the shape, average crystal gain size and sheet thickness of the produced sheet and when a strain relief annealing is applied to the produced scratched sheet, the lowered iron loss is returned to the original unimproved value, so that this method is not practical. | {
"pile_set_name": "USPTO Backgrounds"
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Dust collectors are typically used in tandem with hand-held drilling tools such as rotary hammers to collect dust and other debris during a drilling operation to prevent dust and other debris from accumulating at a worksite. Such dust collectors may be attached to a rotary hammer to position a suction inlet of the collector proximate a drill bit attached to the rotary hammer. Such dust collectors may also include an on-board dust container in which dust and other debris is accumulated. Such dust containers are often removable from the dust collector to facilitate disposal of the accumulated dust and debris. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a liquid container.
2. Description of the Related Art
As one of liquid ejection apparatuses that eject liquid on a target, an ink-jet type printer is widely used. This ink-jet type printer includes a carriage and a recording head mounted on the carriage. The ink-jet type printer discharges ink from nozzles formed in the recording head to perform printing on a recording medium while moving the carriage with respect to the recording medium. In addition, in such an ink-jet type printer, an ink cartridge serving as a liquid container for storing ink is provided replaceably, and the ink discharged from the recording head is supplied from the ink cartridge.
Incidentally, in recent years, in the ink-jet type printer described above, printing has been performed on a large print sheet such as an AO size sheet. In such a case, since an amount of ink consumption increases, there is a demand for an ink cartridge that can store a large quantity of ink. If such a large capacity ink cartridge is mounted on a carriage, weight of the carriage increases, and it is likely that a great deal of load is applied to a carriage motor or the like. Therefore, a structure in which an ink cartridge is not mounted on a carriage (so-called off-carriage type) has been generally adopted.
In recent years, it has also been proposed to adopt the off-carriage system for an ink-jet type printer, which is reduced in size and thickness, in addition to the large ink-jet type printer described above.
In the off-carriage system described above, ink packs provided with ink leading members are contained in a container case including a case main body portion and a lid case to form an ink cartridge. In the ink packs contained as described above, the ink leading members are positioned by support portions formed on a front surface of the container case. Reception openings are provided in the centers of the support portions such that needle-like ink introducing members (ink supply needles), which are arranged in a cartridge inserting portion on a recording apparatus side, are relatively stuck into the ink leading members through the reception openings (see JP-A-10-217499).
If the ink supply needles remain stuck in the ink leading portions of the ink packs as described above, there is no leakage of ink. On the other hand, when an ink pack is empty, the ink cartridge is detached from the ink cartridge inserting portion and the ink pack is replaced. When the ink cartridge is detached, leakage of ink occurs because surfaces of exposed ink supply needles are wet with ink or a slight amount of ink scatters in a transition period of the detachment of the ink cartridge. If a user repeats such detachment and attachment of the ink cartridge for a more number of times than normal, the ink leaked as described above accumulates to an amount enough for allowing the ink to flow. Then, the ink flows in a gap part between the case main body portion and a fitting portion of the lid case due to the capillarity to reach a place apart from the support portions.
When the user holds and detaches the ink pack from which the ink flow described above has occurred, a hand of the user is smeared with the ink or the ink smear reaches even to the cartridge inserting portion of the apparatus.
Note that the above-mentioned problem is a problem that should be solved not only in the ink-jet type printer of the off-carriage system but also in an ink-jet type printer of a form for inserting an ink cartridge, which is formed by containing ink packs provided with ink leading members in a container case including a case main body portion and a lid case, into a cartridge inserting portion formed in a carriage.
The invention has been devised in order to solve such a problem, and it is an object of the invention to provide a liquid container that can prevent leaked liquid from invading along the liquid container.
In addition, it is another object of the invention to provide a liquid container that can prevent flow of liquid due to the capillarity.
The ink-jet type printer described above has been diversified in that a range of application thereof has been expanded and higher definition print image quality has been demanded. In accordance with the diversification, types of ink used in the ink-jet type printer have also been diversified, and for example, a cartridge is replaced according to contents of printing, and the printing is executed. In the ink-jet type printer in which an operation for replacing an ink cartridge according to contents of printing is performed, an ink cartridge provided with information on ink is required. Thus, proposals have been made for an ink cartridge mounted with semiconductor storing means that is capable of reading out and writing data in order to manage types of ink and a remaining amount of ink in the ink cartridge (see JP-A-2002-1979 and JP-A-2002-19135).
In addition, a proposal has been made for an ink cartridge that includes, in addition to a circuit board storing ink information, an ink pack serving as a bag for ink and a waste ink collector for collecting waste ink such that printing according to a characteristic of ink can be performed surely (see Japanese Patent No. 3222454).
However, the ink cartridge has a problem in that, since the circuit board is close to a position to which ink is supplied and a position from which the ink is discharged, the ink adheres to the circuit board due to scattering, dripping, or the like of the ink. More specifically, the scattering, the dripping or the like of the ink is caused from an ink supply port for supplying the ink or a waste ink collecting port for collecting waste ink when the ink cartridge is attached to and detached from a printer body. Therefore, when the scattering, the dripping, or the like of the ink occurs, the ink adheres to the circuit board that is provided in a position adjacent to the ink supply port or the waste ink collecting port.
The invention has been devised in order to solve the problem, and it is an object of the invention to provide a liquid container that does not affect an electronic device even in the case in which ink drips or scatters from a liquid supply port or a liquid collecting port. | {
"pile_set_name": "USPTO Backgrounds"
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1. Technical Field
The present invention relates generally to optical character recognition and computer security.
2. Description of the Background Art
Electronic mail (“email”) has become a relatively common means of communication among individuals with access to a computer network, such as the Internet. Among its advantages, email is relatively convenient, fast, and cost-effective compared to traditional mail. It is thus no surprise that a lot of businesses and home computer users have some form of email access. Unfortunately, the features that make email popular also lead to its abuse. Specifically, unscrupulous advertisers, also known as “spammers,” have resorted to mass electronic mailings of advertisements over the Internet. These mass emails, which are also referred to as “spam emails” or simply “spam,” are sent to computer users regardless of whether they asked for them or not. Spam includes any unsolicited email, not just advertisements. Spam is not only a nuisance, but also poses an economic burden.
Previously, the majority of spam consisted of text and images that are linked to websites. In the last few years, spammers are sending spam with an image containing the inappropriate content (i.e., the unsolicited message). The reason for embedding inappropriate content in an image is that spam messages can be distinguished from normal or legitimate messages in at least two ways. For one, the inappropriate content (e.g., words such as “Viagra”, “free”, “online prescriptions,” etc.) can be readily detected by keyword and statistical filters (e.g., see Sahami M., Dumais S., Heckerman D., and Horvitz E., “A Bayesian Approach to Filtering Junk E-mail,” AAAI'98 Workshop on Learning for Text Categorization, 27 Jul. 1998, Madison, Wis.). Second, the domain in URLs (uniform resource locators) in the spam can be compared to databases of known bad domains and links (e.g., see Internet URL <http://www.surbl.org/>).
In contrast, a spam email where the inappropriate content and URLs are embedded in an image may be harder to classify because the email itself does not contain obvious “spammy” textual content and does not have a link/domain that can be looked up in a database of bad links/domains.
Similarly, other messages (besides email) may also have embedded images with sensitive text content. It may be desirable to filter the messages for such image-embedded text content, for example, for data leakage or compliance applications.
Extracting text content from images can be a difficult problem, especially for identifying languages with large alphabets (character sets) such as Chinese, Japanese, and other languages with large numbers of characters. The large alphabets (character sets) for Chinese and Japanese each include over two thousand distinct characters. Such languages cause automatic content filtering software to be less useful when dealing with images. For example, an anti-spam engine may fail to detect a spam email with only a picture in it and what the spam email want to say are represented by image format.
Using OCR (optical character recognition) techniques to identify spam images (i.e., images having embedded “spammy” content) have been proposed because OCR can be used to identify text in images. In general, use of OCR for anti-spam or other content-sensitive message filtering applications would involve performing OCR on an image to extract text from the image, and comparing the extracted text with pre-defined spammy or other content-sensitive terms to determine if the image contains that content. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a lockout system which is particularly useful on electrical control safety switches arranged on door-like closures which cover openings in fence-like enclosures that are used to guard electrically powered industrial equipment in order to restrict access to such equipment.
Safety switches are frequently used on door-like closures in factories so that when the closures are opened, the electrical power supply to the enclosed equipment is interrupted and remains interrupted until the closures are returned to their closed positions. Thus, workmen entering an enclosed area to maintain or to service or to otherwise contact the enclosed equipment are protected against movement of the equipment or electrical shocks while they are within the enclosure or guarded area.
A problem encountered is that if the closure is inadequately or accidentally closed, the switch on the closure may be inadvertently activated and complete the safety circuit to the equipment allowing equipment to operate in an unsafe manner. Hence, the invention herein relates to a lockout system which prevents an open closure from being inadvertently closed so that the door switch is inadvertently activated when someone is within the enclosure. The lockout system prevents the safety switch from completing the safety circuit when the door is opened and prevents the door from being unintentionally closed.
In more detail, the use of walls or fences or other restraining barriers around equipment within a factory is common. Particularly where robots or other electrically powered equipment are used, it is common to erect a protective fence or wall or other enclosure around the equipment. The electrical power supplied to the equipment, as a safety measure, may be interrupted whenever a door-like closure is opened so that someone may enter the enclosure and contact the equipment without fear of hazardous motion or of electrical shocks. However, there remains a possibility that someone may inadvertently close the door or that the door may otherwise swing shut when a workman is within the enclosure and does not want to have the electrical current actuated or the equipment in operation or any type of motion by the equipment.
The term door is intended here to encompass closures, such as doors, hatches, gates, etc., whether of a swinging or sliding type, which is used to close an opening in some sort of wall or fence or other restraining barrier. Thus, the term “door” is used in a generic sense herein.
A common type of electrical safety switch for such doors may be formed with two components, one mounted on the edge of a door and the other mounted on the frame or edge of the opening which the door normally closes. The two components cooperate to control the flow of power to equipment or other power using paraphernalia. Such two-part or two-component switches may be operated to allow current flow by having cooperating sensing devices which sense or signal when the two components are aligned and are closely adjacent. Conversely, when the two components are not aligned and/or are spaced apart widely, the switch is deactivated and interferes with the flow of current. Thus, sensing devices, for example, may be in the form of photoelectric cells, or magnetic sensors, or radio signals, or induction sensors or mechanical contacts, or key lock devices, or the like.
For practical use, the sensors that are used should operate to control or switch on the flow of current when the sensors are properly aligned and the door is closed relative to the door frame or the edge of the opening and, conversely, to switch off to prevent the flow of current when that condition is not present. Thus, the lockout system is intended to normally assist in locking the door in its closed position and, conversely, to prevent the door from closing after it is opened until someone manually operates the lockout system to again close the door. Hence, unless the door lockout system is manually and deliberately operated, the door will not close and, accordingly, the switch components will not be properly aligned so that electrical current flow to the enclosed equipment is prevented. The lockout system preferably includes an arrangement whereby the workmen must manually unlock the door to open the door, and once the door is open, the system prevents the door from closing until a deliberate manual act is performed. Hence, the lockout system will automatically keep the door from closing until it is deliberately intended to be closed.
The lockout system provides a simple, inexpensive construction which may be installed on pre-existing enclosures.
Thus, it is intended to be “fool proof” so that it may not be accidentally or inadvertently deactivated when the door is in open position. Consequently the system prevents the accidental flow of electrical current to enclosed electrically powered equipment when the door to the enclosure is not deliberately closed. | {
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The brain is one example of a network (i.e., a neural network). Neural disorders are ultimately manifested as abnormal interactions in neural networks controlling specific functions. Very little is known about the workings of neural networks. Although a wealth of knowledge has been accumulated concerning the morphology, biochemistry, electrophysiology, synaptic activity and development of individual neurons, much less is known about how they work together in small or larger ensembles to accomplish their function. There are three main reasons for this lack of knowledge. First, there has been so much preoccupation with individual cells and chemicals (e.g., neurotransmitters) that neural networks as carriers of information have been overshadowed. Second, technology for studying neural networks has been largely absent. And third, the theoretical background for studying neural networks has not yielded any rigorous and robust measure of neural network function. | {
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Integrated circuit memory devices typically include address inputs for receiving address signals to identify a memory location which is to be accessed for storing or retrieving data. The received address signals are decoded and used to access memory cell locations. In conventional memory devices, memory cells are accessed through access, or isolation Transistors. These Transistors are activated by a signal provided on a "wordline" coupled to a gate of the Transistor. As such, the signal on the wordline must remain valid while the memory cell is accessed. Because the wordline signal is typically generated using the address signals, if the address signals are changed during an access operation, memory data read or write operations may be prematurely interrupted resulting in a memory operation error.
For the reasons stated above, and for other reasons stated below which will become apparent to those skilled in the art upon reading and understanding the present specification, there is a need in the art for a memory device which latches a wordline signal to maintain access to memory locations while allowing externally provided address signals to change. In particular, memory devices which contain multiple banks of memory cells and share common address inputs will experience faster data access by allowing address signal changes to occur for a first memory bank while simultaneously maintaining access to a second memory bank. | {
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The Java Platform Enterprise Edition (Java EE) provides an industry-standard specification by which Java software applications can be developed for use within an enterprise environment. Such software applications can then be run in an appropriate application server, for example, an Oracle WebLogic Server.
Application servers which conform to the Java EE specification are generally designed to be extensible, by providing interfaces that allow for embedding of third-party components. Embedded components benefit from the infrastructure provided by the application server, for example its clustering, transaction, and security support. Such embedded components can be used to augment the capabilities of the application server with additional functionality and services, such as portals, business process management, and cloud support.
Technologies such as OSGi also enable third-party components to be integrated into the application server environment in a modular fashion.
A typical enterprise environment supports clustering of a plurality of application server instances, which can then be managed as a logical domain. Preferably, the configuration of embedded components should be similar among all clustered instances within a domain. This allows the functionality and services provided by the embedded components to be distributed throughout the cluster, which in turn enables fault-tolerance and improved throughput.
However, in some application server environments, an embedded component may be required to use its host's proprietary configuration synchronization interface to replicate its configuration to other clustered instances. This creates lock-in of the embedded component implementation with its host application server. In other environments, the host application server may not provide interfaces for synchronization of configuration across its clustered instances, in which cases an embedded component developer is forced to either use a proprietary interface, or not support clustering. These are generally the types of environment in which embodiments of the invention can be used. | {
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The present disclosure relates generally to backlights for displays, and more particularly to light emitting diode based backlights.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Liquid crystal displays (LCDs) are commonly used as screens or displays for a wide variety of electronic devices, including portable and desktop computers, televisions, and handheld devices, such as cellular telephones, personal data assistants, and media players. Traditionally, LCDs have employed cold cathode fluorescent light (CCFL) light sources as backlights. However, advances in light emitting diode (LED) technology, such as improvements in brightness, energy efficiency, color range, life expectancy, durability, robustness, and continual reductions in cost, have made LED backlights a popular choice for replacing CCFL light sources. However, while a single CCFL can light an entire display; multiple LEDs are typically used to light comparable displays.
Numerous white LEDs may be employed within a backlight. Depending on manufacturing precision, the light produced by the individual white LEDs may have a broad color or chromaticity distribution, for example, ranging from a blue tint tint to a yellow tint or from a green tint to a purple tint. During manufacturing, the LEDs may be classified into bins with each bin representing a small range of chromaticity values emitted by the LEDs. To reduce color variation within a backlight, LEDs from similar bins may be mounted within a backlight. The selected bins may encompass the desired color, or target white point, of the backlight.
High quality displays may desire high color uniformity throughout the display, with only small deviations from the target white point. However, it may be costly to utilize LEDs from only one bin or from a small range of bins. Further, the white point of the LEDs may change over time and/or with temperature, resulting in deviations from the target white point. | {
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1. Field of the Invention:
This invention relates to a fire-retardant gel electrolyte which can be employed in a lithium-type secondary cell or the like instead of a non-aqueous electrolyte solution and a cell using the fire-retardant gel electrolyte.
2. Prior Art:
Recently, an intense attention has been paid to a lithium secondary cell which is composed of a positive electrode made of a lithium-containing compound, a negative electrode made of a material such as lithium, a lithium alloy and a carbonaceous material capable of occluding lithium, and a non-aqueous electrolyte solution composed of a non-aqueous solvent and a salt of an electrolyte dissolved in the non-aqueous solvent, because the lithium secondary cell exhibits a relatively large electromotive force (output) and a relatively high energy density as compared with aqueous electrolyte solution-type secondary cells such as a lead cell, a nickel-cadmium cell or the like.
In order to further improve a performance of such a lithium secondary cell, it is important to take into account a property of the electrolyte which gives an influence on an ionic conductivity between the positive and negative electrodes, in addition to selection of materials used for the negative positive electrodes. As a consequence, a variety of proposals concerning non-aqueous solvents and electrolyte salts has been made to obtain an electrolyte having a high ionic conductivity and an enhanced resistance to a high voltage.
For example, the non-aqueous solvent used conventionally includes a carbonate-series solvent such as propylene carbonate, ethylene carbonate, methyl-ethyl carbonate and dimethyl carbonate, .gamma.-butyl lactone, 1, 2-dimethoxy ethane, methyl propionate, butyl propionate and the like.
Further, the electrolyte salt reported and used conventionally includes LiPF.sub.6, LiClO.sub.4, LiBF.sub.4, LiCF.sub.3 SO.sub.3, LiAsF.sub.6, LiN(CF.sub.3 SO.sub.2).sub.2, LiC(CF.sub.2 SO.sub.2).sub.3, or the like.
However, the non-aqueous electrolyte solution composed of the non-aqueous solvent and the electrolyte salt enumerated above has a relatively small heat capacity, as described in Japanese patent laid-open publication No. 184870/92. As a result, in the event that the cell is accidentally placed in the flame, the solvent is caused to be evaporated in association with an increase of the ambient temperature, so that there is a risk that the solvent vapor fires.
One measure for preventing the above-mentioned problem has been proposed in Japanese patent laid-open publication No. 184870/92 in which a fire-retardant phosphoric acid ester is added to the electrolyte solution to eliminate the possible firing.
However, an organic ester compound such as phosphoric acid ester has such a problem that an electrochemical resistance to an oxidation/reduction reaction is relatively small. If such phosphoric acid ester is applied to a lithium secondary cell having an advantageously high terminal voltage, for example, 4 volts or higher, phosphoric acid ester is subjected to an undesired oxidation/reduction reaction in association with repeated charging and discharging cycles, which results in deterioration of a discharging capacity of the cell. | {
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The present invention relates to a control method for computers, and more particularly to a method of running a plurality of operating systems (OSs) on a single computer.
A general computer runs only a single OS which manages computer resources such as a processor, a memory and a secondary storage and performs resource scheduling in order to realize an efficient operation of the computer.
There are various types of OSs, some excellent in batch processing, some excellent in time sharing system (TSS), and some excellent in graphical user interface (GUI).
There are needs of using a plurality of OSs on a single computer. For example, a mainframe is desired to operate both OS for executing practical online transaction processings and OS for research and development. There is also a requirement for running both OS having comparative GUI and OS excellent in real time.
However, each OS is assumed to manage computer resources by itself and a concurrent presence of a plurality of OSs is impossible unless some measure is incorporated.
As a measure for operating a plurality of OSs on a single computer, a virtual machine system realized by a mainframe is known (refer to “Modern Operating Systems”: Andrew S. Tanenbaum, Prentice Hall, 1992 (pp. 21 to 22). In a virtual machine system, a virtual machine control program dominantly manages all hardware resources, and virtualizes these resources to configure the virtual machine system. A controller of a virtual machine system virtualizes physical memories, input/output (I/O) devices, external interrupts and the like.
For example, each divided physical memory is handled by each virtual machine as if it is a memory starting form the address “0”. Device numbers identifying I/O devices are similarly virtualized. In addition, a magnetic disk is also virtualized by dividing its memory area.
Each OS is scheduled by the control program so that OS runs on a virtual machine configured by the control program. However, in a virtual machine system of a mainframe, since computer resources are completely virtualized and divided, the controller of a virtual machine becomes complicated.
Setting a control register from an OS running a virtual machine and a privilege instruction such as an I/O instruction issued by the OS, are required to be emulated by a virtual machine control program if there is no specific hardware support. A problem of a large overhead therefore occurs. In practice, this overhead is reduced in a mainframe which configures virtual machines, by adding hardware realizing processor functions and micro codes specific to the virtual machine.
The virtual machine system aims at completely virtualizing computer resources, so that the system becomes complicated. Furthermore, to realize a high performance of a virtual machine, specific hardware is required.
A mircokernel is known as techniques for providing a single computer with interface with a plurality of OSs (refer to “Modern Operating Systems”: Andrew S. Tanenbaum, Prentice Hall, 1922 (pp. 637 to 641)). If a microkernel is used, an operating system server is configured on the microkernel, the server providing an OS function transparent to a user which utilizes computer resources via the server. If each OS is provided with such a server, a user is provided with various OS environments.
With the microkernel system, however, it is necessary to newly configure an operating system server compatible with a microkernel. In many cases, currently existing OSs are modified so as to run on the microkernel. The core portion of each OS such as scheduling and memory management is required to be modified. There are many portions to be modified. In addition, these modified portions are related also to the main part of each OS, so that the modification work is complicated and difficult.
Still further, although the operating system server utilizes services of the microkernel, this operation is not used by a general OS so that an overhead increases and the system performance is degraded. | {
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The invention concerns a hinge with a hinge cup which can be inserted into a boring in a furniture part, with a damper housing fixed onto the hinge cup.
Hinges fitted with a damper which brakes furniture doors during closing are known in the art from EP 1 199 433 A2, from the Austrian utility model AT 005 477 U1 and the German utility models DE 201 15 250 U and DE 202 05 905 U. The problem addressed by the present invention is to create a hinge with a damper such that the damper can be used universally. | {
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The search for processes to provide alternate feedstocks for fuels and chemicals, and particularly high quality diesel fuels and high value mixed linear alpha-alcohols, has been prompted due to the potential shortage of traditional petroleum reserves, and the increasing instability of international hydrocarbon resources.
Almost as old as the Fischer-Tropsch process for making hydrocarbons is the Fischer-Tropsch process for making alcohols. The Fischer-Tropsch process is carried out by passing a mixture of CO and H2 over a catalyst for the hydrogenation of CO. Numerous catalysts and catalytic methods have been studied in an attempt to provide a viable method for the production of aliphatic alcohols from synthesis gas.
Three main types of processes have been proposed for preparing alcohols from gaseous mixtures comprising carbon monoxide and hydrogen. One of these is a modified Fischer-Tropsch process which involves the use of alkali metal-containing iron based catalysts. Generally, this process suffers from poor selectivity and low productivity. Another process is the iso-butyl synthesis as used in Europe between 1935 and 1945. This process is analogous to the methanol synthesis process and utilizes a similar catalyst, i.e. zinc chromite, modified by addition of an alkali metal salt, at high temperature and high pressure. Typically, the main products from this process comprise methanol (50%), ethanol (20-40%), n-propanol, and higher alcohols which are predominantly non-linear primary and secondary alcohols. The third process was originally assigned to Dow Chemical Company, in which primarily C1 to C4 mixed alcohols are produced in good yield over a supported catalyst based on molybdenum disulfide.
A typical review article related to alcohols preparation is R. B. Anderson et al. “Industrial and Engineering Chemistry” vol. 44, No. 10, pp. 2418-2424. A number of catalysts containing zinc, copper, chromium, manganese, thorium and iron, occasionally promoted with alkali or other materials for making various alcohols are listed in this article.
U.S. Pat. No. 4,504,600 provides a CO hydrogenation process for producing alcohols utilizing thallium-promoted iron-based catalysts. A mixture of CO and H2 is selectively converted to liquid C6˜C12 hydrocarbon containing C6˜C12 alcohols hydrocarbons in an amount of 4˜8 wt. %, and methane in an amount of 1 wt. %, relative to the total produced hydrocarbons, with a CO2 selectivity of 12˜18 mol. %.
U.S. Pat. No. 4,513,096 discloses a method for reacting carbon monoxide and hydrogen in a slurry phase to form light hydrocarbons and alcohols, in the presence of iron-containing activated carbon.
U.S. Pat. Nos. 4,551,444 and 4,886,651 provide a modified copper based methanol synthesis catalyst, especially a thoria and zirconia promoted copper catalyst, over which higher yields of C1 to C6 mixed alkanols and hydrocarbons are formed from synthesis gas at reaction conditions.
U.S. Pat. No. 4,562,174 discloses a catalyst comprised of copper and zinc oxides, and optionally manganese oxide or manganese and cobalt oxides and a stabilizer such as chromic, ceric, magnesium or aluminum oxides, over which C1 to C6 mixed alcohols and light hydrocarbons are produced through CO hydrogenation.
U.S. Pat. No. 4,780,481 describes a process for manufacturing a mixture of saturated primary alcohols by reacting carbon monoxide with hydrogen in the presence of a catalyst formed essentially of copper, cobalt and zinc, promoted by alkali and alkaline earth metals and optionally zirconium and rare earth metals.
U.S. Pat. No. 4,943,551 describes a catalyst composition for the production of methanol and higher saturated aliphatic alcohols from synthesis gas. The catalyst consists essentially of copper, thorium, zirconium and an alkali metal.
U.S. Pat. No. 4,725,626 discloses a catalyst and a process for the production of alcohols from CO and H2. The catalyst has the formula: RuCuaMbAcN2Ox, wherein A is an alkali metal or an alkaline earth metal or mixture thereof, and M is Mo and W or mixtures thereof.
U.S. Pat. No. 4,751,248 discloses a process for converting synthesis gas (H2/CO) to aliphatic alcohols containing at least 2 carbon atoms, comprising the steps of passing the synthesis gas firstly through a catalyst zone wherein the catalyst comprises (a) Co metal and/or Co oxide and (b) MgO and/or ZnO (preferably MgO), and then through a catalyst zone wherein the catalyst comprises (c) Cu metal and/or Cu oxide and (d) ZnO.
U.S. Pat. Nos. 4,980,389 and 4,983,638 disclose a catalyst and a method for preparing a mixture of lower aliphatic alcohols. The method includes reacting a mixture of CO and H2 under suitable conditions of temperature and pressure, in the presence of a catalyst composition comprising rhodium, cobalt, molybdenum and a combination of potassium and rubidium.
U.S. Pat. No. 4,749,724 describes a process for forming an alcohol fraction boiling in the boiling range of motor gasoline that is enriched in higher alcohols, comprising the step of contacting a mixture of H2 and CO, and a lower alkanol with a catalyst comprising (1) molybdenum, tungsten or a mixture thereof in free or combined form; (2) an alkali or alkaline earth element; and (3) a support.
U.S. Pat. Nos. 4,675,344 and 4,775,696 state that a method for controlling the ratio of methanol and higher alcohols produced in a process for making mixed alcohols by contacting a H2/CO mixture with a catalyst which contains molybdenum, tungsten or rhenium, said method comprising adjusting the concentration of a sulfur releasing substance in the feedstock.
U.S. Pat. Nos. 4,661,525, 4,752,622, 4,824,869 and 4,825,013 disclose that mixed alcohols are produced from a mixture of CO and H2 using an easily prepared catalyst which comprises a catalyst metal, a co-catalyst metal, and a support, wherein the catalyst metal is molybdenum, tungsten or rhenium, the co-catalyst metal is cobalt, nickel or iron, and the catalyst is promoted by an alkali or alkaline earth metal.
U.S. Pat. Nos. 4,752,623, 4,831,060 and 4,882,360 disclose a process for selectively making C1-C6 alcohols from synthesis gas, comprising the step of contacting a mixture of H2/CO with a catalytic amount of a catalyst wherein the catalyst is consisted of (1) a catalytically active metal, such as molybdenum, tungsten or rhenium; (2) a co-catalytic metal, such as cobalt, nickel, or iron; (3) an alkali or alkaline earth metal; (4) an optional support. The catalyst has to be sulfidized before the contact.
More recently, U.S. Pat. Nos. 6,248,796 and 6,753,353 disclose a method for the production of mixed alcohols by using a sulfidized transition metal catalyst selected from Group VI metals, such as molybdenum or tungsten; nano-sizing the metal catalyst during its synthesis; suspending the catalyst in solvents to form a slurry; adding a sulfur-containing material to extend the catalyst life; and contacting this slurry with a mixture of CO and H2.
Previous catalytic methods have been notably effective for converting CO and H2 feedstocks into hydrocarbons and C1 to C6 alcohols, but none has been particularly effective for providing a substantial yield of a higher aliphatic C2 to C18, especially C6 to C18 alcohols at a moderate temperature and pressure.
An extensive amount of works have been carried out in order to modify and improve the selectivity of a process for producing C6-C18 alcohols, especially C6-C18 linear alcohols, particularly under conditions that low methane and CO2 are produced. Such a process is desired since C6-C18 linear alcohols are industrially important and used in detergents, surfactants, lubricants and plasticizers.
Thus far, no one has disclosed an activated carbon supported cobalt based catalyst which affords improved yields of paraffins and mixed linear alpha-alkanols from the reaction between carbon monoxide and hydrogen, which minimizes the need for an additional step for the separation of products from the catalyst and which permits the use of high space velocities.
There are two processes for the production of synthetic linear alcohols which are (a) ALFOL® process and EPAL® process, based on the work of Prof. Dr. Ziegler, using organic aluminum compounds and (b) an oxo-process (hydroformylation). The former process involves five steps of: hydrogenation, ethylation, growth reaction, oxidation and hydrolysis, while the latter process consists of the reaction of olefins with a H2/CO gas mixture, in the presence of a suitable catalyst, wherein alpha-olefins yield approximately equal amounts of linear and branched aldehydes, and branched alkenes can also be used in this process due to double-bond being isomerized in the presence of the same catalyst. For a long time, paraffin-based processes were predominant for the production of olefins, especially used for detergents, now ethylene has became a preferable raw material. The principal steps in oxo-process are ethylene oligomerization, isomerization and metathesis.
Naphtha is the most common feedstock sent to naphtha cracking units for the production of ethylene. A typical naphtha feedstock contains a mixture of paraffinic, naphthenic, and aromatic hydrocarbons with varied molecular weight and molecular structure. The compositions of naphtha feedstocks vary considerably, while the composition has a significant impact on ethylene and byproduct yields. Normal and branched paraffins convert to ethylene in a cracker, but the ethylene yield from n-paraffin is much greater than those from others. Naphtha is also used primarily as feedstocks for producing a gasoline component having high octane value via a catalytic reforming process. The naphtha distillates produced from Fischer-Tropsch process contains predominantly n-paraffins having 5 to 11 carbon atoms, which are excellent feedstocks for the production of ethylene.
Clean diesel fuels that contain no or almost no sulfur, nitrogen, or aromatics, are or will likely be demanded largely as diesel fuels or in blending diesel fuels. Clean diesel fuels with some mixed alcohols, having relatively high cetane number, are particularly valuable. Typical petroleum-derived distillates are not clean, in that they typically contain significant amounts of sulfur, nitrogen, and aromatics, and they have relatively low cetane numbers. Clean diesel fuels can be produced from petroleum-derived distillates through severe hydrotreating at great expense. The production of clean, high cetane number distillates from Fischer-Tropsch waxes has been discussed in various literatures, but it is reported in few literatures that the catalyst can be used to directly convert synthesis gas to diesel distillates with high quality and with some level mixed alcohols.
Thus, there is a need for an activated carbon supported cobalt based catalyst that cut off the heavier end of the Schultz-Flory distribution, over which mixed linear alpha-alcohols (C2-C18) and the middle distillates (naphtha distillates and diesel fuels) with sulfur-free, nitrogen-free or aromatics-free can be directly synthesized from synthesis gas under moderate condition. | {
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With multi-core cable, core connections have been made in practice, for example, by offsetting or penciling the core insulations, applying the core connector, wrapping with high voltage insulation tapes, applying an electrically conductive outer shielding, and filling the splice case or enclosure with insulating material. The wrapping of the insulating tapes has to be performed with care while keeping to relatively close dimensional tolerances to obtain the desired stress control. With single core cable connections, this does not normally cause any particular difficulties. With multi-core cable connections, however, when wrapping the insulation tape, the other cores must be worked around. Relatively long end portions of the cores have to be exposed to permit spreading the cores apart far enough to permit the winding to be performed with the necessary accuracy. But often, in cable manholes, there is little cable length available to make the connection; in that case only relatively short end portions of the cores may be exposed, and the winding is very difficult, and often inaccurate.
There are other types of core connections known in which the stress control shielding consists of a prefabricated sleeve-like elastomeric body which, similar to the above-described outer splice case, may be kept in readiness on one of the core ends to be connected and after the conductor connector has been applied, may be pushed over the connection area into a position in which it extends from core insulation to core insulation being seated thereon in sealed relationship. Such prefabricated elastomeric bodies may include an electrically conductive cylindrical lining and an external conductive coating, so that the lining will form an equipotential area in contact with the connector, and the conductive coating may be connected to the protecting layers of the two core ends as disclosed in U.S. Pat. No. 3,485,935. When using these known core connections for making the overall cable connection of multi-core cables, at least one core end must be so long that the elastomeric body may be pushed therealong into a position in which the spreading apart of the core ends as much as necessary and the fitting of the conductor connectors are not obstructed. In most applications the space required for this is not available in the longitudinal direction of the cable, because medium voltage multi-core cables are mainly used as buried cables for 12 to 20 kV 3-phase current power supply mains, for example in densely populated areas. It has, therefore, been necessary in this principal field of application to use the above-described tape wrapping technique, although this is particularly difficult, particularly in restricted spaces. | {
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Sintered members are used as machine parts in various applications, such as automobiles, OA equipment, and home appliances. Sintered members are suitable as materials of complex three-dimensional products because sintered members can be produced to have good mechanical properties, such as strength and abrasion resistance, and have shapes similar to final products.
With the trend toward reduction in weight of machine parts, there is a need for sintered members formed of more lightweight materials, and thus materials containing aluminum alloys have been proposed. For example, PTL 1 discloses a liquid phase sintered aluminum alloy formed so as to contain hard particles in an aluminum alloy for the purpose of achieving high strength and high abrasion resistance. This liquid phase sintered aluminum alloy is produced by compacting a mixed powder of an aluminum alloy powder and hard particles to form a green compact, subjecting the green compact to liquid phase sintering to give a sintered body, and further subjecting the sintered body to sizing and heat treatment. | {
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Modern computer systems place a high importance on maintaining data and application security. In a modern distributed and/or virtual computer system where a plurality of users, services, applications, virtual machines, controlling domains and hosts may have access to a computer system, maintaining data and application security may be a difficult problem. In a distributed and/or virtual computer system environment, for example, where the computer system resources may be provided by a computing resource service provider, customers may also wish for additional security for confidential data and/or privileged applications, safeguarding such data and/or applications from others and even from the computing resource service provider.
Encrypting data and/or applications may help ameliorate the security risks, but the owners of the data and/or applications often desire additional assurances. For example, customers may desire assurances that users, services, applications, virtual machines, controlling domains and hosts may not access confidential data that the customer has saved in a data storage repository on a computer system accessible by one or more users, services, applications, virtual machines, controlling domains or hosts. Without such assurances, customers may be reluctant to use the computer system services provided by the computing resource service provider and, likewise, such computing resource service providers may be apprehensive about hosting such sensitive data on hosts accessible to other customers. Furthermore, application of additional security measures for protecting sensitive data, such as additional and/or more computationally intensive encryption techniques, may be costly to both the customer and the computing resource service provider and may lead to decreased system performance, decreased resource availability, and a degradation in customer satisfaction. | {
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A wide variety of soil release agents for use in domestic and industrial fabric treatment processes such as laundering, fabric drying in hot air clothes dryers, and the like are known in the art. Various soil release agents have been commercialized and are currently used in detergent compositions and fabric softener/antistatic articles and compositions. Such soil release polymers typically comprise an oligomeric or polymeric ester "backbone".
Soil release polymers are generally very effective on polyester or other synthetic fabrics where the grease, oil or similar hydrophobic stains spread out and form a attached film and thereby are not easily removed in an aqueous laundering process. Many soil release polymers have a less dramatic effect on "blended" fabrics, that is on fabrics that comprise a mixture of cotton and synthetic material, and have little or no effect on cotton articles. The reason for the affinity of many soil release agents for synthetic fabric is that the backbone of a polyester soil release polymer typically comprises a mixture of terephthalate residues and ethyleneoxy or propyleneoxy polymeric units; the same or closely analogous to materials that comprise the polyester fibers of synthetic fabric. This similar structure of soil release agents and synthetic fabric produce an intrinsic affinity between these compounds.
Extensive research in this area has yielded significant improvements in the effectiveness of polyester soil release agents yielding materials with enhanced product performance and formulatability. Modifications of the polymer backbone as well as the selection of proper end-capping groups has produced a wide variety of polyester soil release polymers. For example, end-cap modifications, such as the use of sulfoaryl moieties and especially the low cost isethionate-derived end-capping units, have increased the range of solubility and adjunct ingredient compatibility of these polymers without sacrifice of soil release effectiveness. Many polyester soil release polymers can now be formulated into both liquid as well as solid (i.e., granular) detergents.
In contrast to the case of polyester soil release agents, producing an oligomeric or polymeric material that mimics the structure of cotton has not resulted in a cotton soil release polymer. Although cotton and polyester fabric are both comprised of long chain polymeric materials, they are chemically very different. Cotton is comprised of cellulose fibers that consist of anhydroglucose units joined by 1-4 linkages. These glycosidic linkages characterize the cotton cellulose as a polysaccharide whereas polyester soil release polymers are generally a combination of terephthalate and oxyethylene/oxypropylene residues. These differences in composition account for the difference in the fabric properties of cotton versus polyester fabric. Cotton is hydrophilic relative to polyester. Polyester is hydrophobic and attracts oily or greasy dirt and can easily be "dry cleaned". Importantly, the terephthalate and ethyleneoxy/propyleneoxy backbone of polyester fabric does not contain reactive sites, such as the hydroxyl moieties of cotton, that interact with stains in different manner than synthetics. Many cotton stains become "fixed" and can only be resolved by bleaching the fabric.
Until now the development of an effective cotton soil release agent for use in a laundry detergent has been elusive. Attempts by others to apply the paradigm of matching the structure of a soil release polymer with the structure of the fabric, a method successful in the polyester soil release polymer field, has nevertheless yielded marginal results when applied to cotton fabric soil release agents. The use of methylcellulose, a cotton polysaccharide with modified oligomeric units, proved to be more effective on polyesters than on cotton.
For example, U.K. 1,314,897, published Apr. 26, 1973 teaches a hydroxypropyl methyl cellulose material for the prevention of wet-soil redeposition and improving stain release on laundered fabric. While this material appears to be somewhat effective on polyester and blended fabrics, the disclosure indicates these materials to be unsatisfactory at producing the desired results on cotton fabric.
Other attempts to produce a soil release agent for cotton fabric have usually taken the form of permanently modifying the chemical structure of the cotton fibers themselves by reacting a substrate with the polysaccharide polymer backbone. For example, U.S. Pat. No. 3,897,026 issued to Kearney, discloses cellulosic textile materials having improved soil release and stain resistance properties obtained by reaction of an ethylene-maleic anhydride co-polymer with the hydroxyl moieties of the cotton polymers. One perceived drawback of this method is the desirable hydrophilic properties of the cotton fabric are substantially modified by this process.
Non-permanent soil release treatments or finishes have also been previously attempted. U.S. Pat. No. 3,912,681 issued to Dickson teaches a composition for applying a non-permanent soil release finish comprising a polycarboxylate polymer to a cotton fabric. However, this material must be applied at a pH less than 3, a process not suitable for consumer use nor compatible with laundry detergents which typically have a pH greater than 7.5.
U.S. Pat. No. 3,948,838 issued to Hinton, et alia describes high molecular weight (500,000 to 1,500,000) polyacrylic polymers for soil release. These materials are used preferably with other fabric treatments, for example, durable press textile reactants such as formaldehyde. This process is also not readily applicable for use by consumers in a typical washing machine.
U.S. Pat. No. 4,559,056 issued to Leigh, et alia discloses a process for treating cotton or synthetic fabrics with a composition comprising an organopolysiloxane elastomer, an organosiloxaneoxyalkylene copolymer crosslinking agent and a siloxane curing catalyst. Organosilicone oligomers are well known by those skilled in the art as suds supressors
Other soil release agents not comprising terephthalate and mixtures of polyoxy ethylene/propylene are vinyl caprolactam resins as disclosed by Rupert, et alia in U.S. Pat. Nos. 4,579,681 and 4,614,519. These disclosed vinyl caprolactam materials have their effectiveness limited to polyester fabrics, blends of cotton and polyester, and cotton fabrics rendered hydrophobic by finishing agents.
Examples of alkoxylated polyamines and quaternized alkoxylated polyamines are disclosed in European Patent Application 206,513 as being suitable for use as soil dispersents, however their possible use as a cotton soil release agent is not disclosed. In addition, these materials do not comprise N-oxides, a key modification made to the polyamines of the present invention and a component of the increased bleach stability exhibited by the presently disclosed compounds.
It has now been surprisingly discovered that effective soil release agents for cotton articles can be prepared from certain modified polyamines. This unexpected result has yielded compositions that are effective at providing the soil release benefits once available to only synthetic and synthetic-cotton blended fabric.
The present invention provides for soil release agents that are effective on articles that comprise cotton as well as articles that comprise blends of cotton and certain synthetic fibers. The present invention also provides for laundry detergent compositions that are solid or liquid. The solid laundry detergents may be in the form of granules, flakes, pastes, gels or laundry bars. The liquid detergents can have a wide range of viscosity and may include heavy concentrates, pourable "ready" detergents, or light duty fabric pre-treatments.
The compounds of the present invention are compatible with other laundry detergent additives and adjuncts and when formulated with polyester soil release agents, now provide soil release on all fabrics. | {
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Olefins are traditionally produced from petroleum feedstock by catalytic or steam cracking processes. These cracking processes, especially steam cracking, produce light olefin(s) such as ethylene and/or propylene from a variety of hydrocarbon feedstock. Ethylene and propylene are important commodity petrochemicals useful in many processes for making plastics and other chemical compounds. Ethylene is used to make various polyethylene plastics, and in making other chemicals such as vinyl chloride, ethylene oxide, ethylbenzene and alcohol. Propylene is used to make various polypropylene plastics, and in making other chemicals such as acrylonitrile and propylene oxide.
The petrochemical industry has known for some time that oxygenates, especially alcohols, are convertible into light olefin(s). There are numerous technologies available for producing oxygenates including fermentation or reaction of synthesis gas derived from natural gas, petroleum liquids, carbonaceous materials including coal, recycled plastics, municipal waste or any other organic material. Generally, the production of synthesis gas involves a combustion reaction of natural gas, mostly methane, and an oxygen source into hydrogen, carbon monoxide and/or carbon dioxide. Syngas production processes are well known, and include conventional steam reforming, autothermal reforming or a combination thereof.
Methanol, the preferred oxygenate for light olefin production, is typically synthesized from the catalytic reaction of hydrogen, carbon monoxide and/or carbon dioxide in a methanol reactor in the presence of a heterogeneous catalyst. For example, in one synthesis process methanol is produced using a copper/zinc oxide catalyst in a water-cooled tubular methanol reactor.
The preferred oxygenate to olefin conversion process is generally referred to as a methanol-to-olefin(s) process, where the oxygenate, e.g. methanol, is converted in a reactor to primarily ethylene and/or propylene in the presence of a catalyst—typically a molecular sieve catalyst made from a molecular sieve catalyst composition. The oxygenate to olefin reaction uses a catalyst that is maintained under operating conditions with carbonaceous deposits thereon. The carbonaceous deposits are often referred to as coke. Catalyst, for the purpose herein, is classified according to the size of the catalyst. Catalyst particles are larger than catalyst fines. Catalysts particles are typically retained in the reactor by the particle size separators that disengage or separate the catalyst particles from the effluent stream, which effluent stream passes through the particle size separators into the product recovery train. Catalyst fines are carried into the effluent stream.
Typically catalyst particles above 40 microns are added to the reactor to catalyze a reaction. During the reaction, the catalyst develops carbonaceous deposits. Withdrawing a portion of the catalyst from the reactor and burning the carbonaceous deposits off of the catalyst particles controls the aggregate amount of the carbonaceous deposits on catalyst in the reactor. As the catalyst particles travel through the reactor, they break down into smaller particles due to contact with the various parts of the reactor. As they break down in size, they eventually become catalyst fines. Catalyst fines will have the same overall amount of carbonaceous deposits as catalyst particles. Particle size separators, such as cyclones, are placed in the reactors and regenerators to retain useful catalyst particles in the reactor/regenerator system. Catalyst fines (typically less than 40 microns) are generally not retained by the particle size separators and leave the regenerator through the flue. Catalyst fines in the reactor become carried into the effluent with the product.
The effluent from an oxygenate to olefins reaction comprises a considerable amount of water when compared to other olefin forming processes. This large amount of water and the presence of catalyst with carbonaceous deposits creates unique challenges for effluent clean up and recovery. Catalyst for an oxygenate to olefin reaction is typically a molecular sieve catalyst. It is formed into catalyst particles. The presence of the catalyst fines and large quantities of water make removal and disposal of both the water and catalyst fines a unique problem in the oxygenate to olefin process.
U.S. Pat. No. 6,403,854 describes a two stage quench for use with the oxygenate conversion process. The first stage quench removes catalyst fines. But there is no guidance on how to dispose of the catalyst fines after it is removed from the effluent.
Therefore, it would be desirable to have a process for the disposal and handling of catalyst fines that improves process efficiency. It would also be advantageous to have a catalyst fines handling process that removes carbonaceous deposits from the catalyst before the catalyst fines are disposed. | {
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1. Field of Invention
The present invention is directed to golf balls, and more particularly to a multilayer golf ball having a center compression, core diameter, mantle hardness and cover hardness that provides superior playability capabilities with respect to softness and spin without sacrificing superior distance capabilities.
2. Description of Related Art
There are a number of physical properties that affect the performe of a golf ball. The core of the golf ball is the source of the ball's energy. Among other things, the core affects the ball's “feel” and its initial velocity. The “feel” is the overall sensation transmitted to the golfer through the golf ball after striking a ball. The initial velocity is the velocity at which the golf ball travels when first struck by the golf club. The initial velocity, together with the ball's trajectory, determine how far a shot will travel.
Until the late 1960's most golf balls were constructed as three-piece wound balls. In the three-piece wound ball, a solid or liquid-filled center is wound with rubber windings to form a core, which is then enclosed within a cover of compounds based on natural (balata or guttta percha) or synthetic transpolyisoprene. During the manufacturing process, after the liquid-filled center is formed, it is frozen to make it as hard as possible so that it will retain its spherical shape while the rubber thread is wrapped around it.
These three-piece wound balls were known and are still known to provide acceptable flight distance and soft feel. Additionally, due to the relative softness of the balata cover, skilled golfers are able to impart various spins on the ball in order to control the ball's flight path (e.g. “fade” or “draw”) and check characteristics upon landing on a green.
In an attempt to produce golf balls with the feel of a traditional three-piece wound golf ball various approaches were taken to duplicate the properties of balata without the materials inherent shortcomings of poor cut and shear resistance and high cost of manufacture. The first attempt at duplicating balata covers was through the use of low modulus ionomers.
These low modulus ionomer polymers produced covers with properties similar to balata but also with the inherent shortcomings of poor cut and shear resistance. Additionally these low modulus ionomer covers tended to go “out of round” quicker than traditional wound three-piece balls with balata covers. The low modulus ionomer covers were improved by blending with higher modulus ionomers but at the expense of loss of feel.
Another approach to providing a golf cover with the properties of balata without its shortcomings was described in U.S. Pat. No. 5,334,673 (the '673 patent) assigned to the Acushnet Company. The '673 patent discloses a cover composition comprising a diisocyanate, a polyol and a slow reacting polyamine curing agent.
With the advent of new materials developed through advances and experimentation in polymer chemistry, two-piece golf balls were developed. The primary difference between a two-piece golf ball and a three-piece golf ball is the elimination of the rubber thread windings found in the three-piece balls. A relatively large solid core in a two-piece ball takes the place of the relatively small center and thread windings of a three-piece ball core having the same overall diameter. With the elimination of the thread windings, there is no need to freeze the core during the manufacturing process of the two-piece golf ball.
Two-piece balls have proven to be more durable than three-piece balls when repeatedly struck with golf clubs and more durable when exposed to a variety of environmental conditions. An example of these environmental conditions is the high temperature commonly experienced in an automobile trunk. In addition, two-piece balls are typically less expensive to manufacture than the three-piece wound balls. However, two-piece balls are, in general, considered to have inferior characteristics of feel and workability when compared to three-piece balls. Generally and historically, two-piece balls use harder cover materials for increased durability. The “hardness” of a golf ball can affect the “feel” of a ball and the sound or “click” produced at contact. “Feel” is determined as the deformation (i.e. compression) of the ball under various load conditions applied across the ball's diameter. Generally, the lower the compression value, the softer the “feel.” The cores in two-piece golf balls are typically larger than the centers in three-piece golf balls.
In contrast, traditional three-piece golf balls with their smaller centers historically use softer cover materials. These softer cover materials result in a lower initial velocity when compared to two-piece golf balls. However, this difference in the initial velocity may be somewhat made up by the windings in the traditional three-piece golf ball.
Ball flight performance is also influenced by dimples formed on the cover. Dimples provide aerodynamic properties that influence flight characteristics. The dimples on a golf ball are important in reducing drag and increasing lift. Drag is the air resistance that acts on the golf ball in the opposite direction from the balls flight direction. As the ball travels through the air, the air surrounding the ball has different velocities and, thus, different pressures. The air exerts maximum pressure at the stagnation point on the front of the ball. The air then flows over the sides of the ball and has increased velocity and reduced pressure. At some point it separates from the surface of the ball, leaving a large turbulent flow area called the wake that has low pressure. The difference in the high pressure in front of the ball and the low pressure behind the ball slows the ball down. This is a primary source of drag for a golf ball.
The dimples on the ball create a turbulent boundary layer around the ball, i.e., the air in a thin layer adjacent to the ball flows in a turbulent manner. The turbulence energizes the boundary layer and helps it stay attached further around the ball to reduce the area of the wake. This greatly increases the pressure behind the ball and substantially reduces the drag.
Lift is the upward force on the ball that is created from a difference in pressure on the top of the ball to the bottom of the ball. The difference in pressure is created by a warpage in the air flow resulting from the ball's back spin. Due to the back spin, the top of the ball moves with the air flow, which delays the separation to a point further aft. Conversely, the bottom of the ball moves against the air flow, moving the separation point forward. This asymmetrical separation creates an arch in the flow pattern, requiring the air over the top of the ball to move faster, and thus have lower pressure than the air underneath the ball. In the early to mid 1900's, almost every golf ball being made had 336 dimples arranged in some form of geometrically repeating pattern. Generally, these balls had about 60% of their outer surface covered by dimples. Over the latter part of the 1900's golf balls were designed with more and more dimples in order to increase surface coverage on the ball. For example, in 1983, Acushnet introduced the TITLEIST 384, which had 384 dimples that were arranged in an icosahedral pattern. About 76% of this balls outer surface was covered with dimples.
A high degree of dimple coverage is beneficial to flight distance, but only if the dimples are of a reasonable size. Golf ball manufacturers have experimented over the years with many different dimple designs, including round, oval, truncated conical, hexagonal, etc. By varying the size, shape and volume of dimples, flight characteristics may be altered. In order to produce more desirable flight characteristics, ball designers have attempted to reduce the surface area on a ball between dimples. This surface area, commonly referred to as land area, can detrimentally effect ball performance. U.S. Pat. No. 4,142,727 to Shaw discloses a dimple pattern using between 240 to 480 dimples to achieve 50 to 60 percent dimple coverage. U.S. Pat. No. 5,957,786 to Aoyama discloses a golf ball dimple pattern based on an icosahedron design. This pattern discloses the use of between 350 to 500 dimples to cover about 80% of the balls surface. As may be seen, dimple patterns and sizes have been widely varied in order to achieve the highest possible dimple coverage on the balls surface.
Most golf balls today use relatively small dimples in order to reduce the amount of land area on the ball surface, and it is not uncommon to have golf balls with over 400 dimples on the surface. However, the only way to increase the number of dimples on a ball is to increase the number of dimple cavities in the ball mold. It is difficult and costly to design and manufacture of molds having high numbers of dimples. Thus, it would be desirable to have a ball with a high percent dimple coverage using larger size and fewer number of dimples on the ball's surface thereby avoiding complex and costly high dimple configuration mold cavities.
Ball manufacturers are bound by regulations of the United States Golf Association (USGA) which control many characteristics of the ball, including the size and weight of the ball, the initial velocity of the ball when tested under specified conditions, the overall distance the ball travels when hit under specified test conditions, and the ball's aerodynamic symmetry. Under USGA regulations, the diameter of the ball cannot be less than 1.680 inches, the weight of the ball cannot be greater than 1.620 ounces avoirdupois, the initial velocity of the ball cannot be greater than 250 feet per second when tested under specified conditions (with a maximum tolerance of +2%), the driver distance cannot exceed 280 yards when tested under specified conditions (with a test tolerance of +6%), and the ball must perform the same aerodynamically regardless of orientation. | {
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PLDs are a well-known type of integrated circuit that may be programmed to perform specified logic functions. One type of PLD, the Field Programmable Gate Array (FPGA), typically includes an array of programmable tiles. These programmable tiles can include, for example, Input/Output Blocks (IOBs), Configurable Logic Blocks (CLBs), dedicated Random Access Memory Blocks (BRAM), multipliers, Digital Signal Processing blocks (DSPs), processors, clock managers, Delay Lock Loops (DLLs), Multi-Gigabit Transceivers (MGTs) and so forth.
Each programmable tile typically includes both programmable interconnect and programmable logic. The programmable interconnect typically includes a large number of interconnect lines of varying lengths interconnected by Programmable Interconnect Points (PIPs). The programmable logic implements the logic of a user design using programmable elements that may include, for example, function generators, registers, arithmetic logic, and so forth.
The programmable interconnect and the programmable logic are typically programmed by loading a stream of configuration data into internal configuration memory cells that define how the programmable elements are configured. The internal configuration memory cells control configurable points, such as CLB functionality or PIPs. The configuration data may be read from memory (e.g., from an external PROM) or written into the FPGA by an external device. The collective states of the individual memory cells then determine the function of the FPGA.
Another type of PLD is the Complex Programmable Logic Device, or CPLD. A CPLD includes two or more “function blocks” connected together and to Input/Output (I/O) resources by an interconnect switch matrix. Each function block of the CPLD includes a two-level AND/OR structure similar to those used in Programmable Logic Arrays (PLAs) and Programmable Array Logic (PAL) devices. In some CPLDs, configuration data is stored on-chip in non-volatile memory. In other CPLDs, configuration data is stored off-chip in non-volatile memory, then downloaded to volatile memory as part of an initial configuration sequence.
For all of these PLDs, the functionality of the device is controlled by data bits provided to the device for that purpose. The data bits can be stored in volatile memory (e.g., static memory cells, as in FPGAs and some CPLDs), in non-volatile memory (e.g., FLASH memory, as in some CPLDs), or in any other type of memory cell.
Some PLDs, such as the Xilinx Virtex® FPGA, can be programmed to incorporate blocks with pre-designed functionalities, i.e., “cores”. A core can include a predetermined set of configuration bits that program the FPGA to perform one or more functions. Alternatively, a core can include source code or schematics that describe the logic and connectivity of a design. Typical cores can provide, but are not limited to, DSP functions, memories, storage elements, and math functions. Some cores include an optimally floor planned layout targeted to a specific family of FPGAs. Cores can also be parameterizable, i.e., allowing the user to enter parameters to activate or change certain core functionality.
Programmable logic devices can be susceptible to functional failure under certain circumstances. The memory cells, for example, that are used to program the PLD's functionality can inadvertently “flip”, or in other words, change their logic state. Such failures may be called single event upsets (SEUs), or radiation induced errors, and can lead to functional failure of the design implemented by the FPGA. | {
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As storage and availability of data grows, a large amount of time is spent identifying data relationships for discovery of new topics. Conventionally, the discovery of new topics is oftentimes performed manually by repetitive work leading to wasting valuable time of users.
Information can have great value. Assembling and maintaining a database to store information involves real costs, such as the costs to acquire information, the costs associated with physical assets used to house, secure, and make the information available, and labor costs to manage the information.
As computer processors are becoming more powerful, it would be particularly useful to save the time that an individual conventionally spends discovering new topics and identifying relationship criteria with existing models, or between the source and the target.
Oftentimes there are simple transformations, or complex topic identification across a large corpus of documents from any subject domain, requiring a lot of user's time for discovery of relationships associated with existing data.
Thus, there is a need for a simple and flexible method which assists users in connection with performing automated discovery of new topics, employing a new topic database for comparison with the existing topics for new application environments. | {
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The present invention relates to electrostatographic image development using magnetic development rollers, and more specifically to a molding assembly for producing electrostatographic magnetic development rollers having precise magnetic development fields.
In the well-known process of electrostatographic printing, a charge retentive surface, typically known as a photoreceptor, is electrostatically charged, and then exposed to a light pattern of an original image to selectively discharge the surface in accordance therewith. The resulting pattern of charged and discharged areas on the photoreceptor form an electrostatic charge pattern, known as a latent image, conforming to the original image. The latent image is developed by contacting it with a fine electrostatically attractable powder known as "toner." Toner is held on the image areas by the electrostatic charge on the photoreceptor surface. Thus, a toner image is produced in conformity with a light image of the original being reproduced. The toner image may then be transferred to a substrate or support member (e.g., paper), and the image affixed thereto to form a permanent record of the image to be reproduced. Subsequent to development, excess toner left on the charge retentive surface is cleaned from the surface.
The process as described above is useful for light lens copying from an original, or for printing electronically generated or stored originals such as with a raster output scanner (ROS), where a charged surface may be imagewise discharged in a variety of ways.
In the process of electrostatographic printing, the step of conveying toner to the latent image on the photoreceptor is known as "development." The object of effective development of a latent image on the photoreceptor is to convey changed toner particles to the latent image at a controlled rate so that the toner particles effectively adhere electrostatically to the image areas on the latent image.
A commonly used technique for development involves the use of a two-component developer material, which comprises, in addition to the toner particles, a quantity of magnetic development carrier granules or beads. The toner particles adhere triboelectrically to the relatively large carrier beads, which are typically made of steel. When the two-component developer material is placed in a magnetic development field, the carrier beads with the toner particles adhering thereto form what is known as a magnetic development brush, wherein the carrier beads form relatively long chains which resemble the fibers of a brush on a developer or development roller. The development roller is typically in the form of a cylindrical sleeve rotating around a fixed assembly of permanent magnets called a magnetic development roller. When the magnetic development brush is introduced into a development zone adjacent the photoreceptor, the electrostatic charge on the photoreceptor will cause the toner particles to be pulled off the carrier beads in the chain and onto the latent image.
Another known development technique involves a single-component developer, that is, a developer which consists entirely of toner. In a common type of single-component system, each toner particle has both an electrostatic charge (to enable the particles to adhere to the photoreceptor) and magnetic development properties (to allow the particles to be magnetic developmentally conveyed to the photoreceptor). Instead of using magnetic development carrier beads to form a magnetic development brush, the magnetized toner particles are caused to adhere directly to a magnetic development roller. In the development zone adjacent the photoreceptor, the electrostatic charge on the photoreceptor will cause the toner particles to be attracted from the magnetic development roller to the photoreceptor. Conventionally, magnetic development rollers each typically includes a plurality of poles for attracting the toner particles. These poles may be positioned on the periphery of the magnetic development roller at such positions to obtain optimum transfer of the toner particles to the photoconductive surface of the drum.
Magnetic development rollers have typically been manufactured with a core or body and magnets positioned on the periphery of the core. Typically the magnets are glued to the periphery of the core. The gluing of magnets to a core contributes to a series of problems. The gluing leads to positioning errors both radially and tangentially, reducing the quality of the roll. Further, added cost may be required to perform subsequent machining of the periphery of the roll to obtain needed accurate tolerances.
More recently, it has been known to mold magnetizable material about a shaft to form a magnetic development roller. The magnetizable material may be one of any suitable moldable materials but, preferably the materials include ferrite, or neodymium iron boron powder. Permanent magnets are imbedded in the molding assembly and are positioned near the periphery of the mold cavity of the assembly where the molded material is to be placed, in an attempt to transfer precise magnetic development fields from the permanent magnets to the magnetizable material within the mold cavity.
The following disclosures may be relevant to various aspects of the present invention. U.S. Pat. No. 5,181,971 discloses a method of manufacturing a magnetic development roller. The method includes the step of disposing a plurality of pairs of magnetic development poles each having the starting magnetic development pole and terminal magnetic development pole of a magnetic development line of force on the peripheral surface of a cavity in a metal mold in which a resin magnet is molded. The lines of flux are in parallel lines
U.S. Pat. No. 5,019,796 discloses an improved bar magnet and method of construction and an improved magnetic development core. An assembly of magnet is shown for use in a processing station of a printing machine. The bar magnet is formed of permanent magnet material having magnetic development domains therein that are magnetized along epicyclical curve segments. The external magnetic development flux density is improved over that of a conventionally magnetized magnet.
U.S. Pat. No. 4,557,582 discloses a magnet roll including magnet pieces adhesively secured to a supporting shaft to increase the magnetic development flux density of a pole. The pieces are disposed so that they have repelling magnetic development forces in the interface between the piece behind the pole and the piece adjacent thereto.
The use of magnetizable material molded about a shaft however is plagued with several problems. Wear of the mold during the molding process, which is attributable to the abrasive nature of the ferrite material within the mold cavity magnets relative to the mold cavity, and which can change the radial positioning of the permanent magnets, thus affecting the strength of the magnetic development fields of a molded roller. Such wear is critical because the effective field of the permanent magnet is reduced as a cubic function of the distance between the permanent magnet and the molded material in the cavity, and because the portion of the mold between the molded material and the magnet must be kept to a minimum.
Further, the circumferential positions of the permanent magnets are critical because those of the poles within the molded magnetic development roller are critical for the proper transfer of the toner within the development unit of the printing machine. The circumferential positioning of the magnetic development fields of the permanent magnets can cause the fields to interact with each other within the mold, thus making it very difficult to predict where to place the permanent magnets within the mold around the mold cavity in order to obtain a magnetic development roller with poles positioned precisely in particular locations about its circumference.
Further, manufacturers may manufacture several different such rolls, rolls with poles in various positions, yet all these rolls must have the same length and diameter in order to fit a particular machine. Such differences in the positioning of the poles requires a separate expensive mold for each particular pole configuration, thus resulting in change-over costs when manufacturing rolls with identical diameters and different pole positions.
Attempts to position the permanent magnets precisely for desired radial and circumferential induced pole positioning, usually require that the positions of the permanent magnets be determined for example by using computer modeling. However, it has been found that even computer modeling is accurate only to approximately plus or minus one to three degrees. Therefore, further trial and error costly, as well as imprecise adjustments are often necessary following even such computer modeling.
There is therefore a need for an efficient, low cost molding assembly for producing electrostatographic magnetic development rollers that have precise magnetic development fields. | {
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Electronic devices and components have found numerous applications in chemistry and biology (more generally, “life sciences”), especially for detection and measurement of various chemical and biological reactions and identification, detection and measurement of various compounds. One such electronic device is referred to as an ion-sensitive field effect transistor, often denoted in the relevant literature as ISFET (or pHFET). ISFETs conventionally have been explored, primarily in the academic and research community, to facilitate measurement of the hydrogen ion concentration of a solution (commonly denoted as “pH”).
More specifically, an ISFET is an impedance transformation device that operates in a manner similar to that of a MOSFET (Metal Oxide Semiconductor Field Effect Transistor), and is particularly configured to selectively measure ion activity in a solution (e.g., hydrogen ions in the solution are the “analytes”). A detailed theory of operation of an ISFET is given in “Thirty years of ISFETOLOGY: what happened in the past 30 years and what may happen in the next 30 years,” P. Bergveld, Sens. Actuators, 88 (2003), pp. 1-20, which publication is hereby incorporated herein by reference (hereinafter referred to as “Bergveld”).
FIG. 1 illustrates a cross-section of a p-type (p-channel) ISFET 50 fabricated using a conventional CMOS (Complementary Metal Oxide Semiconductor) process. However, biCMOS (i.e., bipolar and CMOS) processing may also be used, such as a process that would include a PMOS FET array with bipolar structures on the periphery. Alternatively, other technologies may be employed wherein a sensing element can be made with three-terminal devices in which a sensed ion leads to the development of a signal that controls one of the three terminals; such technologies may also include, for example, GaAs and carbon nanotube technologies. Taking the CMOS example, P-type ISFET fabrication is based on a p-type silicon substrate 52, in which an n-type well 54 forming a transistor “body” is formed. Highly doped p-type (p+) regions Sand D, constituting a source 56 and a drain 58 of the ISFET, are formed within the n-type well 54. A highly doped n-type (n+) region B is also formed within the n-type well to provide a conductive body (or “bulk”) connection 62 to the n-type well. An oxide layer 65 is disposed above the source, drain and body connection regions, through which openings are made to provide electrical connections (via electrical conductors) to these regions; for example, metal contact 66 serves as a conductor to provide an electrical connection to the drain 58, and metal contact 68 serves as a conductor to provide a common connection to the source 56 and n-type well 54, via the highly conductive body connection 62. A polysilicon gate 64 is formed above the oxide layer at a location above a region 60 of the n-type well 54, between the source 56 and the drain 58. Because it is disposed between the polysilicon gate 64 and the transistor body (i.e., the n-type well), the oxide layer 65 often is referred to as the “gate oxide.
Like a MOSFET, the operation of an ISFET is based on the modulation of charge concentration (and thus channel conductance) caused by a MOS (Metal-Oxide-Semiconductor) capacitance constituted by the polysilicon gate 64, the gate oxide 65 and the region 60 of the n-type well 54 between the source and the drain. When a negative voltage is applied across the gate and source regions (VGS<0 Volts), a “p-channel” 63 is created at the interface of the region 60 and the gate oxide 65 by depleting this area of electrons. This p-channel 63 extends between the source and the drain, and electric current is conducted through the p-channel when the gate-source potential VGS is negative enough to attract holes from the source into the channel. The gate-source potential at which the channel 63 begins to conduct current is referred to as the transistor's threshold voltage VTH (the transistor conducts when VGS has an absolute value greater than the threshold voltage VTH). The source is so named because it is the source of the charge carriers (holes for a p-channel) that flow through the channel 63; similarly, the drain is where the charge carriers leave the channel 63.
In the ISFET 50 of FIG. 1, the n-type well 54 (transistor body), via the body connection 62, is forced to be biased at a same potential as the source 56 (i.e., VSB=0 Volts), as seen by the metal contact 68 connected to both the source 56 and the body connection 62. This connection prevents forward biasing of the p+ source region and the n-type well, and thereby facilitates confinement of charge carriers to the area of the region 60 in which the channel 63 may be formed. Any potential difference between the source 56 and the body/n-type well 54 (a non-zero source-to-body voltage VSB) affects the threshold voltage VTH of the ISFET according to a nonlinear relationship, and is commonly referred to as the “body effect,” which in many applications is undesirable.
As also shown in FIG. 1, the polysilicon gate 64 of the ISFET 50 is coupled to multiple metal layers disposed within one or more additional oxide layers 75 disposed above the gate oxide 65 to form a “floating gate” structure 70. The floating gate structure is so named because it is electrically isolated from other conductors associated with the ISFET; namely, it is sandwiched between the gate oxide 65 and a passivation layer 72. In the ISFET 50, the passivation layer 72 constitutes an ion-sensitive membrane that gives rise to the ion-sensitivity of the device. The presence of analytes such as ions in an “analyte solution” 74 (i.e., a solution containing analytes (including ions) of interest or being tested for the presence of analytes of interest) in contact with the passivation layer 72, particularly in a sensitive area 78 above the floating gate structure 70, alters the electrical characteristics of the ISFET so as to modulate a current flowing through the p-channel 63 between the source 56 and the drain 58. The passivation layer 72 may comprise any one of a variety of different materials to facilitate sensitivity to particular ions; for example, passivation layers comprising silicon nitride or silicon oxynitride, as well as metal oxides such as silicon, aluminum or tantalum oxides, generally provide sensitivity to hydrogen ion concentration (pH) in the analyte solution 74, whereas passivation layers comprising polyvinyl chloride containing valinomycin provide sensitivity to potassium ion concentration in the analyte solution 74. Materials suitable for passivation layers and sensitive to other ions such as sodium, silver, iron, bromine, iodine, calcium, and nitrate, for example, are known.
With respect to ion sensitivity, an electric potential difference, commonly referred to as a “surface potential,” arises at the solid/liquid interface of the passivation layer 72 and the analyte solution 74 as a function of the ion concentration in the sensitive area 78 due to a chemical reaction (e.g., usually involving the dissociation of oxide surface groups by the ions in the analyte solution 74 in proximity to the sensitive area 78). This surface potential in turn affects the threshold voltage VTH of the ISFET; thus, it is the threshold voltage VTH of the ISFET that varies with changes in ion concentration in the analyte solution 74 in proximity to the sensitive area 78.
FIG. 2 illustrates an electric circuit representation of the p-channel ISFET 50 shown in FIG. 1. With reference again to FIG. 1, a reference electrode 76 (a conventional Ag/AgCl electrode) in the analyte solution 74 determines the electric potential of the bulk of the analyte solution 74 itself and is analogous to the gate terminal of a conventional MOSFET, as shown in FIG. 2. In a linear or non-saturated operating region of the ISFET, the drain current ID is given as:ID=β(VGS−VTH−½VDS)VDS Equation 1where VDS is the voltage between the drain and the source, and β is a transconductance parameter (in units of Amps/Volts2) given by:
β = μ C ox ( W L ) Equation 2 where μ represents the carrier mobility, Cox is the gate oxide capacitance per unit area, and the ratio W/L is the width to length ratio of the channel 63. If the reference electrode 76 provides an electrical reference or ground (VG=0 Volts), and the drain current ID and the drain-to-source voltage VDS are kept constant, variations of the source voltage Vs of the ISFET directly track variations of the threshold voltage VTH, according to Eq. (1); this may be observed by rearranging Eq. (1) as:
V S = - V TH - ( I D β V DS + V DS 2 ) Equation 3 Since the threshold voltage VTH of the ISFET is sensitive to ion concentration as discussed above, according to Eq. (3) the source voltage VS provides a signal that is directly related to the ion concentration in the analyte solution 74 in proximity to the sensitive area 78 of the ISFET. More specifically, the threshold voltage VTH is given by:
V TH = V FB - Q B C ox + 2 ϕ F Equation 4 where VFB is the flatband voltage, QB is the depletion charge in the silicon and φF is the Fermi-potential. The flatband voltage in turn is related to material properties such as workfunctions and charge accumulation. In the case of an ISFET, with reference to FIGS. 1 and 2, the flatband voltage contains terms that reflect interfaces between 1) the reference electrode 76 (acting as the transistor gate G) and the analyte solution 74; and 2) the analyte solution 74 and the passivation layer 72 in the sensitive area 78 (which in turn mimics the interface between the polysilicon gate 64 of the floating gate structure 70 and the gate oxide 65). The flatband voltage VFB is thus given by:
V FB = E ref - Ψ 0 + χ sol - Φ Si q - Q ss + Q ox C ox Equation 5 where Eref is the reference electrode potential relative to vacuum, ‘ψ0 is the surface potential that results from chemical reactions at the analyte solution/passivation layer interface (e.g., dissociation of surface groups in the passivation layer), and χsol is the surface dipole potential of the analyte solution 74. The fourth term in Eq. (5) relates to the silicon work function (q is the electron charge), and the last term relates to charge densities at the silicon surface and in the gate oxide. The only term in Eq. (5) sensitive to ion concentration in the analyte solution 74 is ψ0, as the ion concentration in the analyte solution 74 controls the chemical reactions (dissociation of surface groups) at the analyte solution/passivation layer interface. Thus, substituting Eq. (5) into Eq. (4), it may be readily observed that it is the surface potential ψ0 that renders the threshold voltage VTH sensitive to ion concentration in the analyte solution 74.
Regarding the chemical reactions at the analyte solution/passivation layer interface, the surface of a given material employed for the passivation layer 72 may include chemical groups that may donate protons to or accept protons from the analyte solution 74, leaving at any given time negatively charged, positively charged, and neutral sites on the surface of the passivation layer 72 at the interface with the analyte solution 74. A model for this proton donation/acceptance process at the analyte solution/passivation layer interface is referred to in the relevant literature as the “Site-Dissociation Model” or the “Site-Binding Model,” and the concepts underlying such a process may be applied generally to characterize surface activity of passivation layers comprising various materials (e.g., metal oxides, metal nitrides, metal oxynitrides).
Using the example of a metal oxide for purposes of illustration, the surface of any metal oxide contains hydroxyl groups that may donate a proton to or accept a proton from the analyte to leave negatively or positively charged sites, respectively, on the surface. The equilibrium reactions at these sites may be described by:AOH⇄AO−+Hs+ Equation 6AOH2+⇄AOH+Hs+ Equation 7awhere A denotes an exemplary metal, HS+ represents a proton in the analyte solution 74. Equation 6 describes proton donation by a surface group, and Equation 7a describes proton acceptance by a surface group. It should be appreciated that the reactions given in Equations 6 and 7a also are present and need to be considered in the analysis of a passivation layer comprising metal nitrides, together with the equilibrium reaction:ANH+3⇄ANH2+H+, Equation 7bwherein Equation 7b describes another proton acceptance equilibrium reaction. For purposes of the present discussion however, again only the proton donation and acceptance reactions given in Equations 6 and 7a are initially considered to illustrate the relevant concepts.
Based on the respective forward and backward reaction rate constants for each equilibrium reaction, intrinsic dissociation constants Ka (for the reaction of Equation 6 and Kb (for the reaction of Equation 7 may be calculated that describe the equilibrium reactions. These intrinsic dissociation constants in turn may be used to determine a surface charge density σ0 (in units of Coulombs/unit area) of the passivation layer 72 according to:σ0=−qB, Equation 8where the term B denotes the number of negatively charged surface groups minus the number of positively charged surface groups per unit area, which in turn depends on the total number of proton donor/acceptor sites per unit area NS on the passivation layer surface, multiplied by a factor relating to the intrinsic dissociation constants Ka and Kb of the respective proton donation and acceptance equilibrium reactions and the surface proton activity (or pHS). The effect of a small change in surface proton activity (pHS) on the surface charge density is given by:
∂ σ 0 ∂ pH S = - q ∂ B ∂ pH S = - q β ox , Equation 9 where βint is referred to as the “intrinsic buffering capacity” of the surface. It should be appreciated that since the values of NS, Ka and Kb are material dependent, the intrinsic buffering capacity βint of the surface similarly is material dependent.
The fact that ionic species in the analyte solution 74 have a finite size and cannot approach the passivation layer surface any closer than the ionic radius results in a phenomenon referred to as a “double layer capacitance” proximate to the analyte solution/passivation layer interface. In the Gouy-Chapman-Stem model for the double layer capacitance as described in Bergveld, the surface charge density σ0 is balanced by an equal but opposite charge density in the analyte solution 74 at some position from the surface of the passivation layer 72. These two parallel opposite charges form a so-called “double layer capacitance” Cdl (per unit area), and the potential difference across the capacitance Cdl is defined as the surface potential ψo according to:σ0=CdlΨ0=−σdl Equation 10where σdl is the charge density on the analyte solution side of the double layer capacitance. This charge density σdl in turn is a function of the concentration of all ion species or other analyte species (i.e., not just protons) in the bulk analyte solution 74; in particular, the surface charge density can be balanced not only by hydrogen ions but other ion species (e.g., Na+, K+) in the bulk analyte solution.
In the regime of relatively lower ionic strengths (e.g., <1 mole/liter), the Debye theory may be used to describe the double layer capacitance Cdl according to:
C dl = k ɛ 0 λ Equation 11 where k is the dielectric constant ∈/∈0 (for relatively lower ionic strengths, the dielectric constant of water may be used), and λ is the Debye screening length (i.e., the distance over which significant charge separation can occur). The Debye length λ is in turn inversely proportional to the square root of the strength of the ionic species in the analyte solution, and in water at room temperature is given by:
λ = 0.3 nm 1 . Equation 12 The ionic strength I of the bulk analyte is a function of the concentration of all ionic species present, and is given by:I=½Σszs2cs, Equation 13where ZS is the charge number of ionic species s and cS is the molar concentration of ionic species s. Accordingly, from Equations 10 through 13, it may be observed that the surface potential is larger for larger Debye screening lengths (i.e., smaller ionic strengths).
The relation between pH values present at the analyte solution/passivation layer interface and in the bulk solution is expressed in the relevant literature by Boltzman statistics with the surface potential ΨO as a parameter:
( pH s - pH B ) = q Ψ 0 k T . Equation 14 From Equations 9, 10 and 14, the sensitivity of the surface potential Ψ0 particularly to changes in the bulk pH of the analyte solution (i.e., “pH sensitivity”) is given by:
ΔΨ 0 Δ pH = - 2.3 kT q a , Equation 15 where the parameter α is a dimensionless sensitivity factor that varies between zero and one and depends on the double layer capacitance Cdl and the intrinsic buffering capacity of the surface Pint as discussed above in connection with Equation 9. In general, passivation layer materials with a high intrinsic buffering capacity βint render the surface potential Ψ0 less sensitive to concentration in the analyte solution 74 of ionic species other than protons (e.g., α is maximized by a large βint). From Equation 15, at a temperature T of 298 degrees Kelvin, it may be appreciated that a theoretical maximum pH sensitivity of 59.2 mV/pH may be achieved at α=1. From Equations 4 and 5, as noted above, changes in the ISFET threshold voltage VTH directly track changes in the surface potential Ψ0; accordingly, the pH sensitivity of an ISFET given by Equation 15 also may be denoted and referred to herein as ΔVTH for convenience. In exemplary conventional ISFETs employing a silicon nitride or silicon oxynitride passivation layer 72 for pH-sensitivity, pH sensitivities ΔVTH (i.e., a change in threshold voltage with change in pH of the analyte solution 74) over a range of approximately 30 mV/pH to 60 mV/pH have been observed experimentally.
Another noteworthy metric in connection with ISFET pH sensitivity relates to the bulk pH of the analyte solution 74 at which there is no net surface charge density σ0 and, accordingly, a surface potential Ψ0 of zero volts. This pH is referred to as the “point of zero charge” and denoted as pHpzc. with reference again to Equation 8 and 9, like the intrinsic buffering capacity βint, pHpzc is a material dependent parameter. From the foregoing, it may be appreciated that the surface potential at any given bulk pHB of the analyte solution 74 may be calculated according to:
Ψ 0 ( pH B ) = ( pH B - pH pec ) ΔΨ 0 Δ pH . Equation 16
Table 1 below lists various metal oxides and metal nitrides and their corresponding points of zero charge (pHpzc), pH sensitivities (ΔVTH), and theoretical maximum surface potential at a pH of 9:
TABLE 1Oxide/Theoretical Ψ0MetalNitridepHpzcΔVTH (mV/pH)(mV) @ pH = 9AlAl2O59.2 54.5 (35° C.)−11ZrZrO25.150150TiTiO25.557.4-62.3201(32° C., pH 3-11)TaTa2O52.9, 2.862.87 (35° C.)384SiSi2N44.6, 6-756.94 (25° C.)251SiSiO22.143297MoMoO31.8-2.148-59396HfHfO27-4-7.650-5881.2WWO20.3, 0.43, 0.550435
Prior research efforts to fabricate ISFETs for pH measurements based on conventional CMOS processing techniques typically have aimed to achieve high signal linearity over a pH range from 1-14. Using an exemplary threshold sensitivity of approximately 50 mV/pH, and considering Eq. (3) above, this requires a linear operating range of approximately 700 mV for the source voltage Vs. As discussed above in connection with FIG. 1, the threshold voltage VTH of ISFETs (as well as MOSFETs) is affected by any voltage VSB between the source and the body (n-type well 54). More specifically, the threshold voltage VTH is a nonlinear function of a nonzero source-to-body voltage VSB Accordingly, so as to avoid compromising linearity due to a difference between the source and body voltage potentials (i.e., to mitigate the “body effect”), as shown in FIG. 1 the source 56 and body connection 62 of the ISFET 50 often are coupled to a common potential via the metal contact 68. This body-source coupling also is shown in the electric circuit representation of the ISFET 50 shown in FIG. 2.
While the foregoing discussion relates primarily to a steady state analysis of ISFET response based on the equilibrium reactions given in Eqs. (6) and (7), the transient or dynamic response of a conventional ISFET to an essentially instantaneous change in ionic strength of the analyte solution 74 (e.g., a stepwise change in proton or other ionic species concentration) has been explored in some research efforts. One exemplary treatment of ISFET transient or dynamic response is found in “ISFET responses on a stepwise change in electrolyte concentration at constant pH,” J. C. van Kerkof, J. C. T. Eijkel and P. Bergveld, Sensors and Actuators B, 18-19 (1994), pp. 56-59, which is incorporated herein by reference.
For ISFET transient response, a stepwise change in the concentration of one or more ionic species in the analyte solution in turn essentially instantaneously changes the charge density σdl on the analyte solution side of the double layer capacitance Cdl. Because the instantaneous change in charge density σdl is faster than the reaction kinetics at the surface of the passivation layer 72, the surface charge density σ0 initially remains constant, and the change in ion concentration effectively results in a sudden change in the double layer capacitance Cdl. From Equation 10, it may be appreciated that such a sudden change in the capacitance Cdl at a constant surface charge density σ0 results in a corresponding sudden change in the surface potential Ψ0. FIG. 2A illustrates this phenomenon, in which an essentially instantaneous or stepwise increase in ion concentration in the analyte solution, as shown in the top graph, results in a corresponding change in the surface potential Ψ0, as shown in the bottom graph of FIG. 2A. After some time, as the passivation layer surface groups react to the stimulus (i.e., as the surface charge density adjusts), the system returns to some equilibrium point, as illustrated by the decay of the ISFET response “pulse” 79 shown in the bottom graph of FIG. 2A. The foregoing phenomenon is referred to in the relevant literature (and hereafter in this disclosure) as an “ion-step” response.
As indicated in the bottom graph of FIG. 2A, an amplitude ΔΨ0 of the ion-step response 79 may be characterized by:
ΔΨ 0 = Ψ 1 - Ψ 2 = σ 0 C dl , 1 - σ 0 C dl , 2 = Ψ 1 ( 1 - C dl , 1 C dl , 2 ) Equation 17 where Ψ1 is an equilibrium surface potential at an initial ion concentration in the analyte solution, Cdl,1 is the double layer capacitance per unit area at the initial ion concentration, Ψ2 is the surface potential corresponding to the ion-step stimulus, and Cdl,2 is the double layer capacitance per unit area based on the ion-step stimulus. The time decay profile 81 associated with the response 79 is determined at least in part by the kinetics of the equilibrium reactions at the analyte solution/passivation layer interface (e.g., as given by Equations 6 and 7 for metal oxides, and also Equation 7b for metal nitrides). One instructive treatment in this regard is provided by “Modeling the short-time response of ISFET sensors,” P. Woias et al., Sensors and Actuators B, 24-25 (1995) 211-217 (hereinafter referred to as “Woias”), which publication is incorporated herein by reference.
In the Woias publication, an exemplary ISFET having a silicon nitride passivation layer is considered. A system of coupled non-linear differential equations based on the equilibrium reactions given by Equations 6, 7a, and 7b is formulated to describe the dynamic response of the ISFET to a step (essentially instantaneous) change in pH; more specifically, these equations describe the change in concentration over time of the various surface species involved in the equilibrium reactions, based on the forward and backward rate constants for the involved proton acceptance and proton donation reactions and how changes in analyte pH affect one or more of the reaction rate constants. Exemplary solutions, some of which include multiple exponential functions and associated time constants, are provided for the concentration of each of the surface ion species as a function of time. In one example provided by Woias, it is assumed that the proton donation reaction given by Equation 6 dominates the transient response of the silicon nitride passivation layer surface for relatively small step changes in pH, thereby facilitating a mono-exponential approximation for the time decay profile 81 of the response 79 according to:
Ψ 0 ( t ) = Δ Ψ 0 ⅇ - 1 / r Equation 18 where the exponential function essentially represents the change in surface charge density as a function of time. In Equation 16, the time constant T is both a function of the bulk pH and material parameters of the passivation layer, according to:
τ = τ 0 × 10 pH / 2 Equation 19 where τ0 denotes a theoretical minimum response time that only depends on material parameters. For silicon nitride, Woias provides exemplary values for τ0 on the order of 60 microseconds to 200 microseconds. For purposes of providing an illustrative example using τ0=60 microseconds and a bulk pH of 9, the time constant r given by Equation 19 is 1.9 seconds. Exemplary values for other types of passivation materials may be found in the relevant literature and/or determined empirically.
Previous efforts to fabricate two-dimensional arrays of ISFETs based on the ISFET design of FIG. 1 have resulted in a maximum of 256 ISFET sensor elements (or “pixels”) in an array (i.e., a 16 pixel by 16 pixel array). Exemplary research in ISFET array fabrication is reported in the publications “A large transistor-based sensor array chip for direct extracellular imaging,” M. J. Milgrew, M. O. Riehle, and D. R. S. Cumming, Sensors and Actuators, B: Chemical, 111-112, (2005), pp. 347-353, and “The development of scalable sensor arrays using standard CMOS technology,” M. J. Milgrew, P. A. Hammond, and D. R. S. Cumming, Sensors and Actuators, B: Chemical, 103, (2004), pp. 37-42, which publications are incorporated herein by reference and collectively referred to hereafter as “Milgrew et al.” Other research efforts relating to the realization of ISFET arrays are reported in the publications “A very large integrated pH-ISFET sensor array chip compatible with standard CMOS processes,” T. C. W. Yeow, M. R. Haskard, D. E. Mulcahy, H. I. Seo and D. H. Kwon, Sensors and Actuators B: Chemical, 44, (1997), pp. 434-440 and “Fabrication of a two-dimensional pH image sensor using a charge transfer technique,” Hizawa, T., Sawada, K., Takao, H., Ishida, M., Sensors and Actuators, B: Chemical 117 (2), 2006, pp. 509-515, which publications also are incorporated herein by reference.
FIG. 3 illustrates one column 85j of a two-dimensional ISFET array according to the design of Milgrew et al. The column 85j includes sixteen (16) pixels 801 through 8016 and, as discussed further below in connection with FIG. 7, a complete two-dimensional array includes sixteen (16) such columns 85j (j=1, 2, 3, . . . 16) arranged side by side. As shown in FIG. 3, a given column 85j includes a current source ISOURCEj that is shared by all pixels of the column, and ISFET bias/readout circuitry 82j (including current sink ISINKj) that is also shared by all pixels of the column. Each ISFET pixel 801 through 8016 includes a p-channel ISFET 50 having an electrically coupled source and body (as shown in FIGS. 1 and 2), plus two switches S1 and S2 that are responsive to one of sixteen row select signals (RSEL1 through RSEL16, and their complements). As discussed below in connection with FIG. 7, a row select signal and its complement are generated simultaneously to “enable” or select a given pixel of the column 85j, and such signal pairs are generated in some sequence to successively enable different pixels of the column one at a time.
As shown in FIG. 3, the switch S2 of each pixel 80 in the design of Milgrew et al. is implemented as a conventional n-channel MOSFET that couples the current source ISOURCEj to the source of the ISFET 50 upon receipt of the corresponding row select signal. The switch S1 of each pixel 80 is implemented as a transmission gate, i.e., a CMOS pair including an n-channel MOSFET and a p-channel MOSFET that couples the source of the ISFET 50 to the bias/readout circuitry 82j upon receipt of the corresponding row select signal and its complement. An example of the switch S11 of the pixel 801 is shown in FIG. 4, in which the p-channel MOSFET of the transmission gate is indicated as S11P and the n-channel MOSFET is indicated as S11N. In the design of Milgrew et al., a transmission gate is employed for the switch S1 of each pixel so that, for an enabled pixel, any ISFET source voltage within the power supply range VDD to VSS may be applied to the bias/readout circuitry 82j and output by the column as the signal VSj. From the foregoing, it should be appreciated that each pixel 80 in the ISFET sensor array design of Milgrew et al. includes four transistors, i.e., a p-channel ISFET, a CMOS-pair transmission gate including an n-channel MOSFET and a p-channel MOSFET for switch S1, and an n-channel MOSFET for switch S2.
As also shown in FIG. 3, the bias/readout circuitry 82j employs a source-drain follower configuration in the form of a Kelvin bridge to maintain a constant drain-source voltage VDSj and isolate the measurement of the source voltage Vsj from the constant drain current ISOURCEj for the ISFET of an enabled pixel in the column 85j. To this end, the bias/readout circuitry 82j includes two operational amplifiers A1 and A2, a current sink ISINKj and a resistor RSDj. The voltage developed across the resistor RSDj due to the current ISINKj flowing through the resistor is forced by the operational amplifiers to appear across the drain and source of the ISFET of an enabled pixel as a constant drain-source voltage VDSj. Thus, with reference again to Eq. (3), due to the constant VDSj and the constant ISOURCEj, the source voltage VSj of the ISFET of the enabled pixel provides a signal corresponding to the ISFETs threshold voltage VTH, and hence a measurement of pH in proximity to the ISFETs sensitive area (see FIG. 1). The wide dynamic range for the source voltage VSj provided by the transmission gate S1 ensures that a full range of pH values from 1-14 may be measured, and the source-body connection of each ISFET ensures sufficient linearity of the ISFETs threshold voltage over the full pH measurement range.
In the column design of Milgrew et al. shown in FIG. 3, it should be appreciated that for the Kelvin bridge configuration of the column bias/readout circuitry 82j to function properly, a p-channel ISFET 50 as shown in FIG. 1 must be employed in each pixel; more specifically, an alternative implementation based on the Kelvin bridge configuration is not possible using an n-channel ISFET. With reference again to FIG. 1, for an n-channel ISFET based on a conventional CMOS process, the n-type well 54 would not be required, and highly doped n-type regions for the drain and source would be formed directly in the p-type silicon substrate 52 (which would constitute the transistor body). For n-channel FET devices, the transistor body typically is coupled to electrical ground. Given the requirement that the source and body of an ISFET in the design of Milgrew et al. are electrically coupled together to mitigate nonlinear performance due to the body effect, this would result in the source of an n-channel ISFET also being connected to electrical ground (i.e., VS=VB=0 Volts), thereby precluding any useful output signal from an enabled pixel. Accordingly, the column design of Milgrew et al. shown in FIG. 3 requires p-channel ISFETs for proper operation.
It should also be appreciated that in the column design of Milgrew et al. shown in FIG. 3, the two n-channel MOSFETs required to implement the switches S1 and S2 in each pixel cannot be formed in the n-type well 54 shown in FIG. 1, in which the p-channel ISFET for the pixel is formed; rather, the n-channel MOSFETs are formed directly in the p-type silicon substrate 52, beyond the confines of the n-type well 54 for the ISFET. FIG. 5 is a diagram similar to FIG. 1, illustrating a wider cross-section of a portion of the p-type silicon substrate 52 corresponding to one pixel 80 of the column 85j shown in FIG. 3, in which the n-type well 54 containing the drain 58, source 56 and body connection 62 of the ISFET 50 is shown alongside a first n-channel MOSFET corresponding to the switch S2 and a second n-channel MOSFET S11N constituting one of the two transistors of the transmission gate S11 shown in FIG. 4.
Furthermore, in the design of Milgrew et al., the p-channel MOSFET required to implement the transmission gate S1 in each pixel (e.g., see S11P in FIG. 4) cannot be formed in the same n-type well in which the p-channel ISFET 50 for the pixel is formed. In particular, because the body and source of the p-channel ISFET are electrically coupled together, implementing the p-channel MOSFET S11P in the same n-well as the p-channel ISFET 50 would lead to unpredictable operation of the transmission gate, or preclude operation entirely. Accordingly, two separate n-type wells are required to implement each pixel in the design of Milgrew et al. FIG. 6 is a diagram similar to FIG. 5, showing a cross-section of another portion of the p-type silicon substrate 52 corresponding to one pixel 80, in which the n-type well 54 corresponding to the ISFET 50 is shown alongside a second n-type well 55 in which is formed the p-channel MOSFET S11P constituting one of the two transistors of the transmission gate S11 shown in FIG. 4. It should be appreciated that the drawings in FIGS. 5 and 6 are not to scale and may not exactly represent the actual layout of a particular pixel in the design of Milgrew et al.; rather these figures are conceptual in nature and are provided primarily to illustrate the requirements of multiple n-wells, and separate n-channel MOSFETs fabricated outside of the n-wells, in the design of Milgrew et al.
The array design of Milgrew et al. was implemented using a 0.35 micrometer (μm) conventional CMOS fabrication process. In this process, various design rules dictate minimum separation distances between features. For example, according to the 0.35 μm CMOS design rules, with reference to FIG. 6, a distance “a” between neighboring n-wells must be at least three (3) micrometers. A distance “a/2” also is indicated in FIG. 6 to the left of the n-well 54 and to the right of the n-well 55 to indicate the minimum distance required to separate the pixel 80 shown in FIG. 6 from neighboring pixels in other columns to the left and right, respectively. Additionally, according to typical 0.35 μm CMOS design rules, a distance “b” shown in FIG. 6 representing the width in cross-section of the n-type well 54 and a distance “c” representing the width in cross-section of the n-type well 55 are each on the order of approximately 3 μm to 4 μm (within the n-type well, an allowance of 1.2 μm is made between the edge of the n-well and each of the source and drain, and the source and drain themselves have a width on the order of 0.7 μm). Accordingly, a total distance “d” shown in FIG. 6 representing the width of the pixel 80 in cross-section is on the order of approximately 12 μm to 14 μm. In one implementation, Milgrew et al. report an array based on the column/pixel design shown in FIG. 3 comprising geometrically square pixels each having a dimension of 12.8 μm by 12.8 μm.
In sum, the ISFET pixel design of Milgrew et al. is aimed at ensuring accurate hydrogen ion concentration measurements over a pH range of 1-14. To ensure measurement linearity, the source and body of each pixel's ISFET are electrically coupled together. To ensure a full range of pH measurements, a transmission gate S1 is employed in each pixel to transmit the source voltage of an enabled pixel. Thus, each pixel of Milgrew's array requires four transistors (p-channel ISFET, p-channel MOSFET, and two n-channel MOSFETs) and two separate n-wells (FIG. 6). Based on a 0.35 micrometer conventional CMOS fabrication process and corresponding design rules, the pixels of such an array have a minimum size appreciably greater than 10 μm, i.e., on the order of approximately 12 μm to 14 μm.
FIG. 7 illustrates a complete two-dimensional pixel array 95 according to the design of Milgrew et al., together with accompanying row and column decoder circuitry and measurement readout circuitry. The array 95 includes sixteen columns 851 through 8516 of pixels, each column having sixteen pixels as discussed above in connection with FIG. 3 (i.e., a 16 pixel by 16 pixel array). A row decoder 92 provides sixteen pairs of complementary row select signals, wherein each pair of row select signals simultaneously enables one pixel in each column 851 through 8516 to provide a set of column output signals from the array 95 based on the respective source voltages VS1 through VS16 of the enabled row of iSFETs. The row decoder 92 is implemented as a conventional four-to-sixteen decoder (i.e., a four-bit binary input ROW1-ROW4 to select one of 24 outputs). The set of column output signals VS1 through VS16 for an enabled row of the array is applied to switching logic 96, which includes sixteen transmission gates S1 through S16 (one transmission gate for each output signal). As above, each transmission gate of the switching logic 96 is implemented using a p-channel MOSFET and an n-channel MOSFET to ensure a sufficient dynamic range for each of the output signals VS1 through VS16. The column decoder 94, like the row decoder 92, is implemented as a conventional four-to-sixteen decoder and is controlled via the four-bit binary input COL1-COL4 to enable one of the transmission gates S1 through S16 of the switching logic 96 at any given time, so as to provide a single output signal VS from the switching logic 96. This output signal VS is applied to a 10-bit analog to digital converter (ADC) 98 to provide a digital representation D1-D10 of the output signal VS corresponding to a given pixel of the array.
As noted earlier, individual ISFETs and arrays of ISFETs similar to those discussed above have been employed as sensing devices in a variety of chemical and biological applications. In particular, ISFETs have been employed as pH sensors in the monitoring of various processes involving nucleic acids such as DNA. Some examples of employing ISFETs in various life-science related applications are given in the following publications, each of which is incorporated herein by reference: Massimo Barbaro, Annalisa Bonfiglio, Luigi Raffo, Andrea Alessandrini, Paolo Facci and Imrich Banik, “Fully electronic DNA hybridization detection by a standard CMOS biochip,” Sensors and Actuators B: Chemical, Volume 118, Issues 1-2, 2006, pp. 41-46; Toshinari Sakurai and Yuzuru Husimi, “Real-time monitoring of DNA polymerase reactions by a micro ISFET pH sensor,” Anal. Chem., 64(17), 1992, pp 1996-1997; S. Purushothaman, C. Toumazou, J. Georgiou, “Towards fast solid state DNA sequencing,” Circuits and Systems, vol. 4, 2002, pp. N-169 to N-172; S. Purushothaman, C. Toumazou, C. P. Ou, “Protons and single nucleotide polymorphism detection: A simple use for the Ion Sensitive Field Effect Transistor,” Sensors and Actuators B: Chemical, Vol. 114, no. 2, 2006, pp. 964-968; A. L. Simonian, A. W. Flounders, J. R. Wild, “FET-Based Biosensors for The Direct Detection of Organophosphate Neurotoxins,” Electroanalysis, Vol. 16, No. 22, 2004, pp. 1896-1906; C. Toumazou, S. Purushothaman, “Sensing Apparatus and Method,” United States Patent Application 2004-0134798, published Jul. 15, 2004; and T. W. Koo, S. Chan, X. Su, Z. Jingwu, M. Yamakawa, V. M. Dubin, “Sensor Arrays and Nucleic Acid Sequencing Applications,” United States Patent Application 2006-0199193, published Sep. 7, 2006.
In general, the development of rapid and sensitive nucleic acid sequencing methods utilizing automated DNA sequencers has significantly advanced the understanding of biology. The term “sequencing” refers to the determination of a primary structure (or primary sequence) of an unbranched biopolymer, which results in a symbolic linear depiction known as a “sequence” that succinctly summarizes much of the atomic-level structure of the sequenced molecule. Nucleic acid (such as DNA) sequencing particularly refers to the process of determining the nucleotide order of a given nucleic acid fragment. Analysis of entire genomes of viruses, bacteria, fungi, animals and plants is now possible, but such analysis generally is limited due to the cost and time required to sequence such large genomes. Moreover, present conventional sequencing methods are limited in terms of their accuracy, the length of individual templates that can be sequenced, and the rate of sequence determination.
Despite improvements in sample preparation and sequencing technologies, none of the present conventional sequencing strategies, including those to date that may involve ISFETs, has provided the cost reductions required to increase throughput to levels required for analysis of large numbers of individual human genomes. The ability to sequence many human genomes facilitates an analysis of the genetic basis underlying disease (e.g., such as cancer) and aging, for example. Some recent efforts have made significant gains in both the ability to prepare genomes for sequencing and to sequence large numbers of templates simultaneously. However, these and other efforts are still limited by the relatively large size of the reaction volumes, as well as the need for special nucleotide analogues, and complex enzymatic or fluorescent methods to “read out” nucleotide sequence. | {
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Tissue-engineering methods for the repair of damaged tissue include (i) forming a tissue from expanded and cultured cells, and transplanting said tissue, (ii) loading expanded and cultured cells at a scaffold and transplanting said scaffold, or (iii) transplanting a scaffold only without cells.
In the case of cartilage regeneration, expanded and cultured cells can be cultured in a chondrogenic medium to form cartilage which is transplanted into a damaged region of cartilage to induce regeneration of cartilage. This method has the advantage of being able to get a definitive therapeutic effect, compared with a method of injecting cells. However, in case the transplanted cartilage tissues do not integrate into the existing tissues, a full therapeutic effect cannot be expected.
This integration (connectivity) may be achieved by carrying out a suture, but in this case the subject tissues must have a structure that can be connected by a suture. It is impossible to apply a suture to a tissue having a structure that cannot be sutured. For example, a tissue that makes up cartilage or bone has limitations for having a suture applied thereon. In particular, when a connection between bone and cartilage is necessary as is in, for instance, the articular cartilage transplantation, it is not easy to carry out such a suture method and there is the shortcoming that a suture area has the potential to cause inflammation. Furthermore, in the case of widely occurring cartilage damage such as degenerative arthritis, it is not easy to find a way to achieve a connection of tissues over a large area.
In order to resolve these problems, a bio-adhesive agent in the form of a paste has been developed which exhibits an adhesive effect between cartilage and cartilage. However, this agent has a major disadvantage due to the fact that the applied adhesive materials formed insulation between the two attached cartilage tissues making it impossible to communicate or exchange the nutrient and/or growth factors and thus two different disconnected cartilage layers are formed bordering the attached surface. Moreover, the previously developed bio-adhesive agents are not effective in achieving a connection (adhesion) between bone and cartilage in the full-thickness wound.
Therefore, there is a need to develop a new bio-adhesive agent that is suitable for the desired tissue regeneration.
Hydroxyapatite is an inorganic substance that constitutes calcified tissues in vivo such as teeth and bone. Hydroxyapatite has the highest crystallinity among calcium phosphate compounds, so its speed of decomposition is accordingly slow, but it has high bio-compatibility as it is a substance comprising natural tissues in vivo. Hydroxyapatite is known to represent the most high bone regeneration effect among various kinds of bone substitutes.
In the previous study, the present inventors devised a method for coating a desired functional group on the surface of hydroxyapatite. Specifically, PCT Publication No. WO 2009/073068, which is an earlier application by the present inventors, disclosed an artificial bone sponge prepared by a process that comprises: modifying the surface of hydroxyapatite using an organic synthesis method so that a functional group such as aldehyde is revealed on the surface of hydroxyapatite; mixing the obtained surface-modified hydroxyapatite with an aqueous solution of chitosan for gellation; and lyophilizing the same. However, WO 2009/073068 teaches only the combination with a second ingredient such as chitosan and does not teach a use of the surface-modified hydroxyapatite alone.
The present inventors have performed continuous study on a use of the surface-modified hydroxyapatite alone without addition of a second ingredient such as chitosan. As a result, they discovered that the surface-modified hydroxyapatite exhibits a satisfactory adhesive strength between bone and cartilage, confirming its potential as a new bio-adhesive agent, and completed the present invention. | {
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1. Field
This invention relates to theater (stage) lighting systems which regulate the luminescence of incandescent lamps. Specifically, this invention provides for a unitized main power unit for use in a theater lighting system wherein the cabinet includes a chassis, main power apparatus drawers, control circuit boards, a power bus unit and equipment rack.
2. State of the Art
A typical theater (stage) lighting system of today is a combination of electrical and electronic components and circuitry. Many of these systems employ solid state electronic circuitry to control the conductivity and, in turn, the power passed by controllable solid state main power apparatus (e.g., silicon-controlled rectifiers (SCR's) and TRIACS) to the incandescent lamps. Normally a plurality of external signal sources supply control signals to a corresponding plurality of control circuits. The control circuits in turn control the conductivity of a corresponding plurality of main power apparatus. The main power apparatus typically supply the power (as regulated by the control circuit) to a selectably variable number of lamps through a patch panel.
Conventionally, each system is made to order (physically and electrically) for a specific application. As constructed, these systems often include a control console which contains the external signal sources and one or more equipment cabinets which contain a plurality of drawers. The drawers, which are removably installed in a chassis contain the control circuitry and the main power apparatus.
The systems as above described are quite costly and difficult to maintain. The main power apparatus generate an appreciable amount of heat which adversely affects the other components and circuitry located in each drawer. Heat induced failures are not uncommon. Notably the drawers are very costly as they contain many components and much circuitry. Thus, many users are inhibited by cost alone from procuring a readily available spare or from acquiring a replacement after failure. In many cases replacement drawers are totally unavailable because the drawers for the particular system were tailor made and have no interchangable counterpart. Similarly, intermediate distributors are prohibited from stocking replacement drawers because of their singular application and/or high cost.
Moreover, it is quite difficult to repair a failed drawer. First, the components and circuitry are fixedly secured (e.g., hard wired) in the drawer, making replacement of defective components difficult. Secondly, sophisticated trouble shooting, often with the drawer energized (hazardous), is needed to diagnose the failure and pinpoint the defect. Accordingly the costly services of a highly skilled technician are needed. Returning a defective drawer to its manufacturer for repair is a feasible alternative; but this too is costly and the time delay may frequently be intolerable by the very nature of the theater business itself.
Many of the dimming systems above described also include direct on-off (non-dim) circuits. A few non-dim circuits are normally provided in each dimming system. These circuits are included because they provide operational flexibility. The non-dim circuits normally include an on-off device in series with a main power apparatus drawer. The on-off device is normally comprised of mercury contacts and holding relays. The voltge applied to the lamps by a non-dim circuit is generally higher (e.g., about 6 volts) than the maximum voltage available from a dimmed circuit. The result is inconsistent maximum illumination between dimmed and non-dim circuits. Operator confusion and error is a frequent result. Further, the cost of providing a non-dim circuit is quite high. An expensive main power apparatus drawer of the same type and configuration as used elsewhere in the system are normally used. Extensive engineering costs arise from the design work needed to provide the non-dim circuit capability. Also additional costs are incurred in obtaining the extra components (e.g., switches and relays) needed for the non-dim circuit. Additional maintenance costs also arise. | {
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This invention relates to expandable arrays of electromagnetic radiating elements and sonar transducers, and more particularly to an expandable array wherein structural rigidity is obtained by urging the radiating elements or transducers against a flexible enclosure.
Arrays of electromagnetic radiating elements and arrays of sonar transducers are sometimes provided with the facility of being stowed in a configuration which is much smaller than the overall dimensions of the array when the radiating elements of transducers are being deployed for the transmission and reception of radiant energy. A situation frequently encountered by sonar transducers is that in which an array of transducers is dropped from an aircraft into the ocean, the array of transducers being stowed in a compact configuration during the airdrop so as to protect the transducers at the time of impact with the surface of the ocean, the transducers then being allowed to move apart from each other under water to provide an array of the transducers having a desired configuration.
A problem arises in that the stowage of transducer elements in a protective housing is best accomplished with a minimum of additional weight and equipment utilized in positioning the trnasducer elements in their respective positions in the underwater array. An additional problem arises in that in certain applications, the array of transducers is required to have a rigid configuration independently of water movement to insure a prescribed pattern of radiation. | {
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The term "to simulate an impulsive causal system" refers to the fact that in generating, collecting and processing seismic information using an impulsive system associated with an earth formation, such systems are based upon the assumption that the responses of the associated elements in the chain are always causal and often precisely or substantially minimum phase. The accuracy of the assumption can be attested to by the fact that processing techniques such as deconvolution yield such accurate results. But in non-impulsive generation of input vibratory waves followed by collection and processing of the received data that include steps related to the cross-correlation of the input and received signals, the elements in the aforementioned chain are not minimum phase. Such realization is seen in the fact that conventional cross-correlated records, the correlation functions are double sided in time; on one side the correlation pulses go forward in time; on the mirror image, the correlation pulses go backward as defined by a series of negative time values. In this regard, see "Reflection Seismology", Kenneth H. Waters, John Wiley & Sons, 1st Ed. at page 80 where a series of typical autocorrelation functions are described.
Likewise, the term "single-sided, with time" refers to the fact that in the non-impulsive system of the present invention, the cross-correlated final records define correlation pulses that begin at time zero exactly coinciding with the time of activation of the non-vibratory source, that is to say, without a mirror image of the correlation pulses being generated about time zero, as heretofore practiced.
The term "distortion-free, after processing" to describe the final records relates to the fact that there should be no undesired or unknown, linear or non-linear change in the waveforms either of the recorded field signals or of the final data after processing has been completed.
Prior to my invention, such distortion could be brought about (i) by the use of generating/recording techniques in the field wherein harmonics of the fundamental dissipate its energy, or (ii) accidentally, where the vibrator pad and the earth do not linearly interface.
Doty et al., U.S. Pat. No. 2,688,124, issued Aug. 31, 1954, for "Method and Apparatus for Determining Travel Time of Signals" describes the well-known VIBROSEIS.RTM. system of Continental Oil Company. In such a system, seismic waves are generated by mechanical vibrators on the earth's surface. Each of the vibrators is firmly anchored to the earth by the combined weight of the source. Peak forces in the neighborhood of 10 to 20 tons (and up to 36 tons) can be developed by the rapid, non-explosive interaction of the base-plate and piston system of each vibrator. Consequently, the weight of each vibrator is proportionally large to maintain the desired, continuous vibrator-earth contact during operations. The waves sent into the earth consist of long, sinusoidal wave trains of predetermined frequency and time duration characteristics rather than the much sharper wave impulses sent into the earth by the explosive sources used prior to the VIBROSEIS.RTM. system, or by "weight drop" methods including those provided by various impulse-coded systems, e.g., the so-called "pulse-coded" techniques.
There may be some confusion as to the differences of the signals produced by the VIBROSEIS.RTM. system and those produced by impulsive sources such as provided by exploding dynamite, exploding mixtures of propane and air, or by "weight drop" methods, including pulse-coded techniques.
It is well known that the capacity of any signal (including seismic signals) to carry information can be measured in a manner analogous to determining the volume of a container. Since volume is the product of height times width times length; similarly, information capacity of a signal is related to a product of amplitude, frequency bandwidth and the length of the signal.
Dynamite as a seismic energy source produces an input signal having considerable amplitude (height) and bandwidth, but has very short length. On the other hand, "non-impulsive" vibrations generated in the manner of a VIBROSEIS.RTM. system have limited amplitude, but such is compensated for by the long length of the input signal and a faithful, continuous reproduction of the control signal over the frequency spectrum of interest. That is to say, in the VIBROSEIS.RTM. system, the amplitude and phase spectra are carefully and continuously controlled so that the resulting energy spectra changes smoothly as a function of time. Thus, a smoothly varying output of desired frequency and duration characteristics is provided in contradistinction to the binary-coded (ON-OFF) square wave output generated by pulse-coded methods in which the energy-per-blow is substantially constant and cannot be so controlled.
A further essential part of the VIBROSEIS.RTM. system lies in the processing of the received data to produce records that tend to show short pulses representing reflections from subsurface interfaces. Such responses are provided by cross-correlating the recorded representation of the vibratory waves sent into the ground with the recorded representation of the waves received subsequently.
There is a further difference between impulsive systems wherein the injected waves are created by explosive sources, and non-impulsive systems. These differences have to do with causation. In the former, the explosion of the source establishes time zero for system operations; in the latter, the vibrations are injected into the earth over a longer time period and then facsimiles of the source output reflected at every interface in the reflection path are identified by cross-correlation. While such process can be regarded as a mechanism for seeking out and marking the individual facsimiles of the input vibrations (signals) in the received signal, the fact that a mirror image in the correlation function often results was heretofore not taken as demonstrating any deleterious effects. This was caused in part by the fact that the correlation process was known to be a convolution, with the signal turned around in time.
The use of cross-correlations, as taught by Doty et al. and many others since, has now become so well known in vibratory seismology that it will be presumed to be well known in the following parts of the present specification; and the description will concern itself only with differences from the prior art.
Erich, U.S. Pat. No. 4,234,053, for "Seismic Exploration Method Using a Rotating Eccentric Weight Seismic Source", describes an exploration method in which a rotating eccentric weight source is used (as a power impactor) to transmit a coded, non-Gaussian impulse input signal into the earth on a substantially constant energy-per-blow basis. An improved representation of the pulsed input signal is correlated with the raw seismic data to provide the field record of interest. But since the impulsive source is also only discontinuously coupled to the earth (i) the interaction of the mass of the eccentric weight source with the spring constant of the earth produces an output dominated by low frequency components and (ii) the pulse shape of the output can vary non-linearly with time. Hence, such a system is limited to those uses where a conventional VIBROSEIS.RTM. system cannot be employed.
Multi-array use of such sources is likewise limited.
Another relevant patent is that of Crook et al., U.S. Pat. No. 3,264,606, issued Aug. 2, 1966, for "Method and Apparatus for Continuous Wave Seismic Prospecting", which teaches driving of vibratory sources (in conjunction with conventional full-wave recording equipment) with pseudo-random codes which, although differing in detail from the preferred codes prescribed here, does share the desirable generic property of "a code sequence which may be represented as a reference time series having a unique auto-correlation function comprising a single major lobe having no side lobes of greater amplitude than the side lobes of the auto-correlation function of statistically unrelated noise components of the composite signal detected at said detecting location" (column 13, lines 32-44).
In my U.S. Pat. No. 4,346,461 for "Seismic Exploration Using Vibratory Sources, Sign-Bit Recording, and Processing That Maximizes the Obtained Subsurface Information", issued Aug. 24, 1982 and assigned to the assignee of the present application, I describe a non-impulsive vibratory system that uses a class of vibrator signals best characterized as Gaussian, zero-mean, and stationary, in conjunction with sign recording of both the injected and received vibrations at the sources and receivers. The stated advantages relate to the channel-capacity economy of sign-bit recording (at both the sources and receivers), and to the distortion-free quality of the final processed records.
I have now discovered that use of the above class of vibrator signals not only does not sacrifice information in the final processed records even though the data is collected by sign-bit recording methods, but such type of vibrator signals also favorably impacts seismic recording and processing operations where vibrator system distortion is present and when full-wave recording is contemplated.
Aside from the above, a paper of A. B. Cunningham, Geophysics, December 1979, Vol. 44, No. 12, pages 1901 et seq., for "Some Alternate Vibrator Signals", works out in mathematical detail expected types of cross-correlation functions from various types of vibrator sweeps, including certain types of pseudo-random sweeps, but not in the context used herein. | {
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Mobile devices are gaining increasing functionality and importance in our daily lives. Accelerometers may be incorporated in these devices for measuring the motion that the device experiences. More and more of these mobile devices have multi-tasking preemptive operating systems that allow the device to run several programs or applications at once. These preemptive operating systems have schedulers to prioritize tasks. In prior implementations, these schedulers based their decision on the priority of each application or function, and occasionally on the time of day. | {
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Many pathogens have the ability to evade the natural defenses of an infected host cell or organism. Consequently, the infected host develops the disease or disorder which is associated with that pathogen.
Treatments for pathogenic infections typically target a distinguishing feature or characteristic of a specific pathogen. For example, acyclovir targets the replication stage of herpesvirus infection, zidovudine/AZT targets the reverse transcriptase of human immunodeficiency virus (HIV), and various protease inhibitors target HIV protease. Generally, however, these therapies have many disadvantages, including limited usefulness for only a specific pathogen, ineffectiveness due to pathogen variation, and toxic side effects. In addition, many of these therapies tend to be slow to develop.
A need exists therefore, for the development of anti-pathogen therapies that are effective for a broad spectrum of pathogens and which overcome disadvantages of existing therapies. | {
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Due to the expanding health consciousness of people around the world, there has been an increasing demand for vitamin C. Also contributing to the demand for ascorbic acid is its widespread use as an antioxidant for preserving food. One approach for satisfying this demand is to achieve increased production of 2-KLG, an intermediate in the production of ascorbic acid. The intermediate, 2-KLG, can be easily converted to ascorbic acid through acid or base catalyzed cyclization. It also has a greater stability and shelf life than ascorbic acid. Therefore, rather than producing ascorbic acid directly, it is more practical to stockpile 2-KLG for subsequent conversion to ascorbic acid.
A number of species of a first group of microorganisms, Erwinia, Acetobacter, and Gluconobacter, can produce 2,5-DKG from D-glucose. A second group of microorganisms from the coryneform group of bacteria (Corynebacterium, Brevibacterium, and Arthrobacter) as well as species of Micrococcus, Staphylococcus, Pseudomonas, Bacillus, and Citrobacter are capable of converting 2,5-DKG, produced by a microorganism of the first group, to 2-KLG. This cofermentation of appropriate microorganisms to produce 2-KLG was simplified by combining the relevant traits of both the Erwinia sp. and the Corynebacterium sp. in a single microorganism (Anderson et al., Science 23: 144 (1985)). This was accomplished by identifying the 2,5-DKG reductase in the Corynebacterium sp. that converts 2,5-DKG into 2-KLG. The gene for this reductase was then cloned and expressed in Erwinia herbicola, a bacterium of the family Enterobacteriaceae that converts D-glucose into 2,5-DKG in a single fermentation. The resulting recombinant bacterial strain, with 2,5-DKG reductase as the pivotal enzyme, was able to convert D-glucose into 2-KLG in a single-fermentation process (Lazarus et al. Fourth ASM Conf. Genet. Molec. Biol. Indust. Microorg., 187-193 (1989)).
Improving the catalytic efficiency of 2,5-DKG reductase, in the single-fermentation process, is a significant way to increase the production of 2-KLG. Also, a purified 2,5-DKG reductase A with increased catalytic activity could be used in an in vitro process for the conversion of 2,5-DKG to 2-KLG. For example, such a process would permit continuous production of 2-KLG through immobilization of the purified enzyme on a solid support.
According to the Michaelis-Menten scheme set out below, the ##STR1## efficiency of an enzymatic reaction can be measured by two kinetic parameters, kcat and Km. The catalytic rate constant, kcat, also known as the turnover number, is a measure of the breakdown of the enzyme-substrate (ES) complex. It also represents the maximum number of substrate molecules (S) converted to product (P) via an ES complex per active site of the enzyme (E) per unit time. Vmax is the maximal velocity or rate of the enzyme catalyzed reaction when the enzyme is saturated with substrate. Therefore, Vmax is constant at saturating substrate concentration and remains unchanged with any increase in substrate concentration. The kcat at saturating substrate concentrations is related to Vmax and the total enzyme concentration, [E.sub.T ], by the following equation: Vmax=kcat [E.sub.T ]. The Michaelis constant, Km, is equal to the dissociation constant of the ES complex. Therefore, Km is a measure of the strength of the ES complex. In a comparison of Km's, a lower Km represents a complex with a stronger, more favorable binding, while a higher Km represents a complex with a weaker, less favorable binding. The ratio, kcat/Km, called the specificity constant, represents the specificity of an enzyme for a substrate, i.e., the catalytic efficiency per enzyme molecule for a substrate. The larger the specificity constant, the more preferred the substrate is by the enzyme.
Impressive yields of 2-KLG have been achieved with a Corynebacterium 2,5-DKG reductase (2,5-DKG reductase A, also known as 2,5-DKG reductase II) (Anderson et al., Science 230: 144-149 (1985); Miller et al., J. Biol. Chem. 262: 9016-9120 (1987)) expressed in appropriate host strains (2,5-DKG producers) such as Erwinia sp. These results have been achieved despite 2,5-DKG reductase A having a low specificity constant for 2,5-DKG. Since Corynebacterium does not naturally encounter 2,5-DKG, it is not surprising that this compound is a poor substrate for 2,5-DKG reductase A.
This low specificity constant for 2,5-DKG reductase A is in contrast to a second, homologous Corynebacterium 2,5-DKG reductase (2,5-DKG reductase B, also known as 2,5-DKG reductase I) that has a greater specificity constant for 2,5-DKG (Sonoyama and Kobayashi, J. Ferment. Technol. 65: 311-317 (1987)). In addition, both 2,5-DKG reductases are homologous to several known aldose and keto-reductases that have greater specificity constants towards their known substrates. Such findings indicate that the active site of 2,5-DKG reductase A is not optimally configured for the catalytic conversion of 2,5-DKG to 2-KLG. Therefore, it appears that in order to optimize 2,5-DKG reductase A specific activity in the single-fermentation process, amino acid substitutions by site-directed mutagenesis must be made to the enzyme's active site.
In addition to improving an enzyme's kinetic parameters, site-directed mutagenesis can increase structural stability by amino acid substitutions, deletions, or insertions. The following are examples of structurally stabilizing mutations. The introduction of new disulfide bonds to create covalent crosslinks between different parts of a protein has been used to improve the thermal stability of bacteriophage T4 lysozyme (Matsumura et al., Nature 342:291-293 (1989)), bacteriophage .lambda. repressor (Sauer et al., Biochem. 25:5992-5998 (1986)), E. coli dihydrofolate reductase (Villafranca etal., Biochem. 26:2182-2189 (1987)), and subtilisin BPN' (Pantoliano et al., Biochem. 26:2077-2082 (1987)). There is a computer program (Pabo et al., Biochem. 25:5987-5991 (1986)) that permits efficient scanning of the crystallographically determined three-dimensional structure of a protein to suggest those sites where insertion of two cysteines might lead to disulfide bonds. Such bonds would not disrupt the larger-scale conformation, while stabilizing the local conformation.
Amino acid substitutions of alanine for glycine in the .alpha.-helix have been shown to increase the thermal stability of the bacteriophage .lambda. repressor (Hecht et al., Proteins : Struct. Funct. Genet. 1:43-46 (1986)) and the neutral protease from Bacillus stearothermophilus (Imanaka et al., Nature 324:695-697 (1986)). An increase in the melting temperature, Tm, for bacteriophage T4 lysozyme was accomplished by the two amino acid substitutions of proline for alanine and alanine for glycine (Matthews etal., Proc. Nat. Acad. Sci. USA 84:6663-6667 (1987)). Replacement of amino acids in the hydrophobic core of a protein with aromatic residues such as tyrosine, especially at positions near preexisting clusters of aromatic side chains, has been shown to promote thermal stability in kanamycin nucleotidyl transferase (Liao et al., Biochem. 83:576-580 (1986)) and bacteriophage .lambda. repressor (Hecht et al., Biochem. 81:5685-5689 (1984)).
Transcriptional and translational control sequences in expression vectors are the key elements required for the high level production of proteins in bacteria. The E. coli Trp, bacteriophage .lambda.P.sub.L, E. coli lac UV5, and the Trp-lacUV5 fusion (Tac) promoters are among the most frequently used prokaryotic promoters (de Boer et al., Proc. Nat. Acad. Sol. USA 80: 21-25 (1983); Sambrook et al., Molecular Cloning, Cold Spring Harbor Press (1989); Remaut et al., Gene 15:81-93 (1981)). There is no way to determine whether a particular protein will be highly expressed upon induction of transcription from these promoters. The translational efficiency of the message, mRNA stability, and the protein's intrinsic stability are the major factors in high-level expression. Therefore, whenever a protein undergoes mutagenesis it is always possible its expression level will be affected.
Site-directed mutagenesis, using synthetic DNA oligonucleotides having the desired sequence, permits substitution, deletion, or insertion of selected nucleotides within a DNA sequence encoding a protein of interest. Recombinant DNA procedures are used to introduce the desired mutation by substituting the synthetic sequence for the target sequence. Development of plasmids containing an origin of replication derived from a filamentous bacteriophage (Vieira and Messing, Methods in Enzymology 153: 3-11 (1987)) permits cloning of fragments into single stranded forms of plasmids capable of autonomous replication. Use of such plasmids eliminates the arduous task of subcloning DNA fragments from plasmids to filamentous bacteriophage vectors. Kits for carrying out site-directed mutagenesis are commercially available.
Mutants of 2,5-DKG reductase A having characteristics which vary from the native enzyme would be useful. In particular, mutants having improved catalytic activity, enhanced thermal stability, and increased expression levels would be useful to extend the commercial utility of the enzyme.
Unfortunately, unless proteins share regions of substantial sequence or structural homology, it is not possible to generalize among proteins to predict, based on a beneficial mutation of one protein, precisely where the sequence encoding another protein should be changed to improve the performance of that protein. Therefore, it is necessary to undertake an analysis of the precise structural and functional features of the particular protein to be altered. This determines which amino acids to alter to produce a desired result, such as increased catalytic activity, thermostability, or expression.
The present invention provides mutated forms of enzymatically active prokaryotic 2,5-DKG reductase A. Analysis of the structure of 2,5-DKG reductase A to select alterations encoding the enzyme to enhance stability, expression, and/or activity of resulting mutants was undertaken. Site-directed mutagenesis of the sequence encoding the enzyme was designed to produce the mutants. | {
"pile_set_name": "USPTO Backgrounds"
} |
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