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The present invention relates to an improved animal collar of the type which can be used on large dogs, cattle, bulls and the like.
By way of background, large animals, such as watch dogs, cattle or bulls frequently have to be tethered by a rope or chain attached to its collar. Animals of the foregoing type are extremely strong and are capable of breaking their collars. Furthermore, animals, such as dogs, will apply jerking forces to their collars which may either break the collars or which may jar the buckles open. | {
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1). Field of the Invention
This invention relates to a computer system and method for transacting bitcoin.
2). Discussion of Related Art
The Bitcoin network is a peer-to-peer payment system having a plurality of nodes that are connected to one another. Bitcoin exchange computer systems allow for users to exchange local currency into or out of bitcoin. Users send payments by broadcasting digitally signed messages to the Bitcoin network. Users may, for example, send and receive payments using mobile applications on mobile devices, client software or a web browser.
Transactions do not explicitly identify the payor and payee by name or wallet. Instead, a bitcoin transaction transfers ownership to a new address, referred to as a “Bitcoin address”. The Bitcoin address is derived from the public portion of one or more cryptographic key pairs. The private portion of a key pair is not disclosed to the public. To send bitcoin sent to an address, a user broadcasts a payment message that is digitally signed with the associated private key.
Participants known as “miners” at miner computer systems verify and timestamp transactions into a shared public database called a “block chain”. The miners are rewarded with transaction fees and newly minted bitcoin for their effort. The miner computer systems are specialized computers that append blocks of transactions to the block chain. Solving a cryptographic puzzle required to append a block carries a reward plus fees included in transactions in the block.
Host computer systems reside at various nodes and may host accounts or “wallets” that allow users to make and accept payments using bitcoin. The wallet stores the public key of the Bitcoin address and its associated private key.
The transfer of bitcoin may be an onerous task if the entire public key of the Bitcoin address has to be copied and transmitted.
When a transaction is made between two wallets at the same or different host computer systems, the transaction is broadcast to the Bitcoin network for block chain verification. Such a block chain verification may take a long time to complete. Miner fees are also associated with such a transfer and have to be paid by a host computer system requesting the transfer.
It may be a security concern for users that their Bitcoin addresses may be stolen from their wallets. Existing systems do not provide a solution for maintaining security of Bitcoin addresses while still allowing the users to use Bitcoin addresses within their wallets for transacting with other users.
A merchant computer system often has an online store and a website. A customer at a customer computer system may use a browser to access the online store via the website. Items are displayed for purchase in a local currency. Exchange rate between bitcoin and local currency changes over short periods of time. The price in local currency may thus change between the time that the local currency is displayed to the customer and the time that the customer decides to make the purchase. As a result, the customer or the merchant may incur a loss in local currency. The customer or merchant may then be reluctant to purchase using bitcoin.
In order for a user to access their wallet, the user may log into their account through the website using a user name and password. If the user name and password become compromised then it may be possible for bitcoin to be stolen out of the wallet. Users may therefore be reluctant to store bitcoin in their wallets without any additional security features.
Bitcoin transacting requires the use of a public key and a private key. The private key is used to sign an authorization and the public key is used to verify the signature. Some users may require control over their private keys in order to ensure to such users that bitcoin transacting will not take place without their express authorization.
Content creators often put a lot of time and energy into their blog posts. These efforts are rarely rewarded because efficient technology does not exist for rewarding bloggers for their efforts. | {
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This invention relates generally to sensor fault detection and more particularly to sensor fault detection in redundant sensor feedback control systems.
Many engineering systems use sensors to monitor and control the operation of the system. That is, the sensors are used to measure one or more system variables such as speed, temperature, pressure and the like. The sensor outputs are then used as feedback in a closed-loop operation to ensure that the system is being operated at the desired conditions, that safety bounds are being observed, and that performance is being optimized.
Although sensors are generally designed to be robust, sensor failure is still a possibility that is often addressed through use of redundant sensors. In such redundant sensor systems, control logic is used to determine which sensor output is used in the feedback loop. Current selection schemes do not fully consider the expected system response relative to command inputs. They also fail to adequately detect certain failure signatures of the sensors in some instances. These failure modes are characterized by either intermittent noise bursts, which occur at levels too small to detect currently, and/or slow gain changes (e.g., drift), which are not observable with current selection schemes. Furthermore, current selection schemes tend to use very complex algorithms comprising multiple layers of logic.
It would be desirable, therefore, to provide a redundant-sensor, feedback control system that considers expected system response and has a sensor selection scheme that can better detect noise burst and gain drift failures in the sensors. It would further be desirable to achieve sensor selection using relatively compact logic.
The above-mentioned need is met by the present invention, which provides a system and method for controlling operation of a component. The system includes at least two sensors that are arranged to sense an operating condition of the component and a controller that controls the component in response to feedback signals output by one or more of the sensors. The controller also determines how the sensor feedback signals are to be used in controlling the component. To this end, the controller includes a model-based statistical filter for each one of the second sensors.
The present invention and its advantages over the prior art will become apparent upon reading the following detailed description and the appended claims with reference to the accompanying drawings. | {
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Such droplet dispensing devices, as those of the present invention, are also sometimes called atomizers, nebulizers and the like. They normally contain a nozzle body on a support part, in particular, a nozzle body of a liquid droplet spray device which dispenses a liquid substance as a liquid droplet spray from the device through the nozzles of the nozzle body. They further consist of an actuator based on a vibrating element which generally causes the liquid to vibrate, to be accelerated and expelled as droplets. They further consist of elements such as liquid space, liquid feed and fluid interface to a reservoir, a reservoir as well as electrical connections between the vibrating element and a corresponding electronic circuitry. Such elements may be contained in the aforementioned support part, in a further support part or they may be contained in a number of support parts. The liquid may be for example an ambient fragrance, a perfume, an insecticide, a liquid pharmaceutical formulation, aqueous based liquids and flammable or combustible liquids.
Such nozzle bodies are sometimes called aperture plates, nozzle arrays, dosing apertures, orifice plates, vibratable membrane members, dosing aperture arrangements, aerosol generators and the like. These terms are hence to be understood as being interchangeable throughout the present document.
Such nozzle bodies and droplet spray devices are well known as such. For example, the document WO2007/062698, in the name of the present Applicant, describes a liquid droplet spray device having a top substrate formed of a main body and of a nozzle body. The nozzle body contains a nozzle array of liquid droplet outlet means allowing a liquid substance contained in the liquid droplet spray device to exit the device, in this case as a spray of droplets. Liquid may be supplied from a replaceable reservoir by way of a wick using capillary flow. Generally, the reservoir is a dispensable refill that needs to be replaced regularly.
The document U.S. Pat. No. 7,017,829 describes a liquid droplet spray device having a wicking apparatus with a wick for use in a replaceable reservoir assembly that contains liquid to be atomized by a vibratory aperture plate configured to dispense the liquid from the reservoir assembly through the orifices of the vibratory plate. In this device, the wick must contact the vibratory plate to allow for capillary flow of liquid from the reservoir to the plate for ejection of the liquid.
Thus, in order to ensure capillary flow, typically, the wick is too long, so that any fabrication tolerance, which might lead to a wick that would be too short, will be overcompensated.
Furthermore, in order to obtain an acceptable draining ratio of the reservoir, the wick should fully contact the inner bottom surface of the reservoir for it to be capable to substantially drain and empty the reservoir. Indeed, if the wick does not reach the plate, no spray can be generated or ejected.
To ensure such contact, again, the wick is typically over-sized so as to compensate for manufacturing tolerances.
However, when a wick that is too long than actually designed is inserted into the reservoir, and positioned below the orifice plate, the wick will inevitably be compressed against the plate and against the inner bottom surface of the reservoir. This compression of the wick then leads to unreliable priming and irregular ejection of liquid each time a reservoir is changed.
In fact, by compressing the wick, which is thus forced into contact to the plate, a so-called squeezing effect is obtained which leads to an increased flow rate of liquid when the wick is first inserted into a replacement reservoir. However, after a certain moment in time, as shown by curve a in FIG. 1, the wick and plate assembly will stabilize in the new position and the flow rate will drop from the increased rate to the intended rate.
Clearly, this is highly undesirable for a consumer, as s/he will have to adjust and re-adjust the flow rate each time the reservoir is replaced in order to have a constant flow rate over time.
Document WO 2005/097349 describes a similar liquid droplet spray device with a wicking apparatus. The wick is formed of two different materials with a rigid main section and a compliant top section. The top compliant section is thus compressible and is pressed into contact with the vibratory orifice plate to allow liquid to flow from the reservoir to the plate by capillary action, and may then be expelled.
Thus, again, the wick is compressed against the plate thus resulting in a squeezing effect, albeit more moderate as compared with the previous document mentioned above, so that here too, an unstable flow rate will occur when inserting a new reservoir.
As for the draining ratio, in this device the rigid main section of the wick would also have to be longer than designed to compensate for manufacturing tolerances and to ensure a full contact with the inner bottom surface of the reservoir.
It is also known to use wick holders so as to correctly and/or securely fix a wick in a reservoir. For example, the document U.S. Pat. No. 6,896,196 describes a liquid droplet spray device with a wicking apparatus that has a wick holder 8 for receiving a wick. The holder is positioned onto a reservoir's bottleneck, and holds the wick in place by way of clamping fingers so as to allow for easy insertion of the wick into the reservoir, while at the same time preventing accidental removal of the wick. However, this document is silent about flow rate or draining ratios.
In view of the above, it is an object of the present invention to provide an innovative wicking apparatus for a droplet spray device that overcomes the inconveniences presented by the prior art documents. | {
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1. Field of the Disclosure
The present disclosure is directed to a piston for use in diesel and other internal combustion engines, and more particularly, a piston comprising two pieces precision cast of steel or similar materials and friction-welded into a complete piston.
2. Description of Related Art
Present diesel and other high performance internal combustion engines are being operated at extremely high combustion pressures and temperatures. For example, many on- and off-road diesel applications operate with diesel fuel injection at pressures in excess of 30,000 psi and exhaust gas turbo-charging which can create intake manifold pressures in excess of 50 psi. In addition, government mandated exhaust emission standards in developed countries and markets including, but not limited to, the United States, Japan, and the EEC require strict control of the combustion processes and strict control of emissions in service, as well as specific performance and emissions control longevity of the engines during on-road, off-road, and marine applications.
The foregoing conditions have resulted in multiple strategies employed to cool the pistons of such engines, the most common of which is to precisely inject substantial amounts of engine oil into chambers formed in the pistons to remove combustion heat.
Presently known piston designs, which are commercially practiced, do not adequately address several extremely critical aspects of piston manufacturing and performance including but not limited to the foregoing. For example, current piston designs struggle to obtain proper dimensional attributes to generally maintain required operational and long-term durable performance of the piston to cylinder bore sealing rings at presently required operating temperatures and pressures as well as minimizing combustion gas blow-by and resultant increased exhaust emissions without costly and extensive machining operations and other additional manufacturing steps. Additionally, current piston designs have problems incorporating an integral reservoir for cooling oil into the piston crown area with adequate volume and highly consistent piston-to-piston volume without the incorporation of separate sealing dams or rings that are mechanically attached to the piston in various manners, all of which require additional machining and manufacturing steps to prepare the piston to accept the separate sealing dams or rings, the inserting and fixing of the sealing rings in the manufacturing process, and the separate manufacture of the sealing dams or rings themselves. Further, current piston designs also have problems with the mechanical failure of the cooling oil reservoir dams or rings and/or the failure of the fixing means of such devices to the piston, causing physical separation from the piston and the resulting loss of cooling oil in one or more pistons and introduction of foreign materials into the interior of the engine and subsequent severe engine damage or failure.
The absence of adequate mechanical support of the piston to cylinder bore sealing ring area of typical pistons including, but not limited to, the flexure of the lower parts of the sealing ring areas and the area where the ring sealing area joins the piston crown often results in cracking and failure of such areas of the piston that incorporate the sealing rings and result in severe engine damage or failure. Also, the absence of adequate mechanical support of the sealing ring area of typical pistons results in the reduction and/or loss of sealing ring performance that causes gas blow-by, which leads to lubricating oil infiltration into the combustion chamber and coating the ring lands with partially combusted lube oil in a process termed “coking.” Each of these conditions increases exhaust emissions and/or causes mechanical failure of the sealing rings and severe engine damage or failure.
It is also known in the art to friction weld two or more previously machined parts of a piston together to permit various configurations to be made that would otherwise be commercially impractical or impossible. Typical two-piece pistons consist of a steel forged crown and a separate skirt, usually forged of the same or a compatible steel alloy which guides the piston assembly in the combustion cylinder of an engine. Prior to friction welding the mating surfaces of the crown and skirt, the crown requires extensive and costly machining operations to provide opposing, axially-aligned bores that are configured to accept a steel pin which joins the piston with a connecting rod. This known piston design is configured to provide a heat and pressure resistant steel crown incorporating the sealing rings and an attached lower member comprised of the skirt. The separate pieces presently start out in as-forged or as/rough-cast condition and are subsequently machined to close tolerances prior to joining by way of friction or inertia welding or another suitable method. However, in each of these processes for producing a piston, precision machining the joining or connecting surfaces that are to be welded together is a costly and additional required prior step/operation to prepare the two piston pieces for the friction welding process.
Known two-piece friction welded pistons also incorporate a cooling oil reservoir which can consist of a recess in the piston crown and/or separate reservoirs in the skirt. Alternatively, a reservoir is formed in the crown and is closed off with a plate assembly, wherein the composite reservoirs communicate with oil spray jets located in the engine block to introduce cooling oil to the underside of the piston crown to reduce the operating temperature of the crown and thus prolong piston life and ensure proper operation of the piston to cylinder bore sealing rings.
Such pistons as described above tend to be very heavy and their configurations are limited by the possible need to join three separate parts to form a complete piston: (1) the steel crown and sealing ring groove section, (2) the skirt section by friction welding and (3) the machining of a receptacle for and the mechanical insertion of an oil dam or plate. Similarly, such piston designs often require multiple methods of forming a cooling oil reservoir/gallery including machining and the mechanical insertion of dams or plates to form such reservoirs.
The incorporation of cooling oil reservoirs or galleries in a piston is also commonly known. This is typically done with the employment of separate dams or plates of various materials which are inserted and fixed beneath the crown area. Alternatively, such reservoirs may also be partially incorporated in one or more of the two-piece friction welded pistons by machining such reservoirs in rough castings or rough forgings prior to joining them in a friction welding process.
Other known piston designs are made of rough cast or as-rough forged as one-piece configurations. However, these designs have several disadvantages including the requirement of extensive post-forging or post-casting machining, the absence of a closed oil gallery formed integrally with the crown, and the absence of lateral/axial support of the lower portion of the sealing ring carrying portion of the piston crown. These design and manufacturing limitations result in requiring a separate oil dam inserted in the crown and the absence of axial and radial support to prevent flexure of the sealing ring portion of the piston. This lack of axial and radial support is known to cause premature flexure failures of the piston crown and the degradation of the piston to cylinder bore sealing ring performance during the service life of the piston which can increase the exhaust emissions of an engine so equipped and can result severe engine damage or failure thereof. The flexure of the lower part of the piston which contains the piston to cylinder bore sealing ring grooves leads to the loss of long-term complete sealing between the piston and the cylinder bore seating rings which, in turn, results in higher oil consumption, combustion blow-by, higher operating temperatures, coking, reduction in service life and increased exhaust emissions which can render the operation of the engine unlawful under certain rules and regulations.
In presently employed friction welded pistons comprising a closed oil gallery, three sealing rings are employed; the first and most adjacent to the piston crown is a one piece compression ring which seals the piston to the cylinder bore during the four cycles of operation. The second and next adjacent ring is also a one piece compression ring which complements the first ring and completes the seal of the piston to the cylinder bore in a similar manner. The third ring is an oil scraper ring which comprises one or more parts which function solely to remove the cooling and lubricating oil from between the piston the cylinder wall during each of the piston strokes
In each of the foregoing configurations of pistons, it is critical to provide a means by which lubricating and cooling oil removed by the third ring during the movements of the piston can be immediately returned to the engine crankcase by way of the cylinder bore and through certain interruptions in the cylindrical piston body as described below
Accordingly, there is a need for a piston that facilitates the passage of the foregoing oil to the cylinder bore and thence the engine crankcase after it is wiped and/or scraped from the cylinder wall. There is also a need for a piston that eliminates additional post-casting and/or post-forging machining including but not limited to that which incorporates and/or affixes separate oil reservoir sealing dams. There is also a need for eliminating post-casting and/or post-forging machining of contact or joining surfaces prior to an inertia or friction welding process for joining at least two separate pieces of a piston. | {
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Well known current steering digital-to-analog converters (DACs) utilize a plurality of current cells for providing a set of well defined currents (i.e. bit currents) controlled by a digital input code, and a plurality of current switches for selectively switching individual ones of the bit currents generated by the current cells through an output resistor such that the weighted sum of currents passing through the output resistor results in an analogue output voltage proportional to the number of current switches which are enabled (i.e. the number of logic high bits of the digital input code).
MOS-based self-calibrated current cells have been in use in current-steering digital-to-analog converters to copy a reference current to several current cells. This basic technique is attractive because of its simplicity, but suffers from several limitations. These limitations include errors due to charge injection and clock feed-through from the digital switches incorporated in the current cells, leakage current from the switches, finite output resistance due to channel length modulation in the output transistors, etc. Some prior art current cells utilize a cascode device to increase the output resistance of the cell and to reduce the coupling of output back to the storage node of the output transistor. However, it has been found that this approach reduces the available voltage swing for the output transistor.
According to one aspect of the present invention, a CMOS-based current cell is provided having higher output resistance than prior art MOS-based current cells, as well as smaller minimum voltage and improved accuracy.
According to one alternative embodiment of the invention, the self-calibrated current cell is implemented using BiCMOS circuitry.
As discussed above, the constant current generated by respective current cells in a current-steering DAC are selectively switched through the output resistor via respective current switches. Prior art bipolar current switches are known to suffer from error in the output current due to the finite current gain of the bipolar switch transistors. As a result, the output current of these prior art current switches differs from the actual bit current generated by its associated current cell by an amount equal to the base current of the bipolar switching transistor. One prior art approach to minimizing this error is to use a Darlington-connected pair of bipolar transistors. However, this approach tends to significantly degrade the switching speed of the circuit.
On the other hand, MOS-based current switches are known to have the advantage of avoiding non-linearity due to base-current mismatches in prior art bipolar transistor switches. However, the MOS devices have a substantially lower transconductance than the bipolar devices for the same current and area, which means it takes a larger voltage swing at the input to switch the current. Since the bit line which carries the input digital code can be loaded with large parasitic capacitance, the overall switching speed of such prior art MOS-based current switches can be significantly degraded.
Therefore, according to another aspect of the present invention, a BiCMOS current switch is provided having no base current error, and which achieves approximately twice the switching speed when compared to prior art MOS current switches. | {
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1. Field of the Invention
The present invention relates in general to tools which are utilized to align railroad rails, and in particular to tools which are utilized to align abutting rails in order to allow welding of the rails together.
2. Description of the Prior Art
All railroads have a considerable investment in their infrastructure. However, the infrastructure requires continuous attention and repair. For example, as rail becomes worn or damaged, it must be replaced. Currently, rail is in relatively long continuous sections; however, these sections must be butt welded together in order to allow for safe and efficient locomotion over the rail. In the prior art, in order to get a good weldment between the end pieces of rail sections, work crews have utilized manual equipment, such as mauls, hammers, and wedges to align the ends of the rails prior to welding. Having railroad crews operate this heavy equipment inherently carries a risk of injury to the employee. For example, when aligning rails with wedges, metal chips may fly off of the wedges when they are struck by hammers during the hammering and wedging operations, resulting in injuries to the workers. Additionally, using the heavy equipment is also inherently risky. Any new rail equipment which can reduce the risk of injury to rail crews is typically quickly and readily adopted by the industry.
It is one objective of the present invention to provide a rail alignment tool which replaces the utilization of mauls, hammers, and wedges in order to align rail ends prior to welding.
It is another objective of the present invention to provide an improved rail alignment tool which allows rail pieces to be aligned, but which only requires the work crew to apply torque to a plurality of threaded bolt members, which is far safer than utilizing mauls, hammers, and wedges.
It is yet another objective of the present invention to provide an improved rail alignment tool which is durable, lightweight, and which requires little or no maintenance, but which is safe to operate and which provides for good alignment of rail sections to allow for good welds to be made between adjoining rail sections. | {
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Microorganisms, such as the Gram-positive microorganism that are members of the genus Bacillus, have been used for large-scale industrial fermentation due, in part, to their ability to secrete their fermentation products into their culture media. Secreted proteins are exported across a cell membrane and a cell wall, and then are subsequently released into the external media. Secretion of polypeptides into periplasmic space or into their culture media is subject to a variety of parameters, which need to be carefully considered in industrial fermentations.
Indeed, secretion of heterologous polypeptides is a widely used technique in industry. Typically, cells are transformed with a nucleic acid encoding a heterologous polypeptide of interest to be expressed and secreted to produce large quantities of desired polypeptides. This technique has been used to produce large quantities of polypeptides. Expression and secretion of desired polypeptides has been controlled through genetic manipulation of the polynucleotides that encode the desired proteins. Despite various advances in protein production methods, there remains a need in the art to provide efficient methods for extracellular protein secretion. | {
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Granulating devices for thermoplastic materials having cutting blades on a cutting head are disclosed in DE-PS 14 54 888 and DE-PS 26 46 309.
In these granulating devices, an alignment of the cutting surfaces of the cutting blades in the cutting head is conducted prior to the actual granulating process by installing the cutting head so that the cutting blades are under slight pressure against the front face of the die plate attached to the granulating head of an extruder.
In this way, the cutting blades are brought in totality into exact alignment on the precision surface of the die plate and any deviations due to tolerances or the like are taken up. This is necessary in order to obtain a satisfactory granulate of uniform grain size.
The same initial conditions can be achieved in the same way after changing individual cutting blades in order to prevent changes in the quality of the granulate over a period of time of operation of the granulating device.
In order to prevent retraction of the cutting blades under the pressure produced by their alignment, the cutting blades are attached to the cutting head at a slight angle of incidence. Since the cutting blades can be removed individually, they can be reground at any time for a separate adjustment and future use. However, this is in fact only of conditional advantage since the new adjustment of the cutting blade after it is attached to the cutting head in a position of alignment with the die plate, a so called "cutting-in" operation, is very time consuming and requires a shutdown of several hours of granulate production. | {
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1. Field of the Invention
The present invention relates generally to memory systems and, more particularly, to a system and method for simultaneously and independently accessing any of a variety of configurations of a data memory and a cache status memory.
2. Related Art
In complex computing environments, difficult computing tasks may be divided into sub-tasks for parallel processing by multiple processors. Typically, at least one processor is designated as a scheduling processor for scheduling tasks to be performed by the other processors.
In a multi-processing system, individual processors may be provided with local memory for storing necessary data and applications software for processing assigned tasks. Often, one processor has access to data and applications software for performing one or more specific type or group of specific types of tasks while other processors have access to different data and software applications programs for performing other types of tasks. This type of system permits specialization of processors and division of labor according to the type of task to be performed.
One drawback of a specialized multi processing system is that when a series of similar tasks must be performed, one or more processors may lack the necessary data or software for processing those tasks. As a result, one or more processors may sit idle while others struggle to process the tasks alone.
In more advanced multi-processing systems, a shared memory is provided for storing necessary data and software for performing one or more anticipated tasks. A shared memory is accessible by most, if not all, processors or requesters within the system so that each processor is capable of performing any assigned task. A central controller or scheduler divides the tasks equally among all processors, thus insuring that the tasks are completed as quickly as possible.
In a shared memory system, however, conflicts may arise if different processors or requesters attempt to access the same location of shared memory. A shared memory system must, therefore, include a conflict resolution method for determining which requestor should be granted access. A conflict resolution device may at times, have to provide a particular requestor with sole access to the requested memory location. Sole access may be required where a processor is assigned a task which requires repeated access to specified data or applications software, especially where the requester may change the value stored in the shared memory.
A typical method of restricting access to specified memory locations is to assign ownership of individual memory locations to particular requesters. A simple ownership scheme may provide only one level of ownership. In such a system, if a requester has ownership over a particular memory location, it has full authority to access, i.e., read from or write to, that location and no other processor is permitted access to that location. More complicated ownership schemes may provide multiple levels of ownership, each higher level providing a higher degree of control. Multiple levels of ownership may be based on priority levels assigned to individual requesters or other factors.
Regardless of the specific type of ownership protocol employed, a shared memory system must provide for storing and updating ownership data.
Typically, ownership data is stored in a reserved portion of the memory which it tracks. The ownership-storing portion of memory is often referred to as cache-status memory or status memory while the tracked-memory is typically referred to as data memory. Because each data memory location requires an associated status data location for storing status data for that data memory location, however, half of the memory device must be reserved for status data. Thus, implementation of such an ownership scheme requires that the system memory capacity be doubled.
A second problem encountered in shared memory systems concerns reading and updating cache status memory. Typically, when a memory controller accesses data memory, it must also read the associated cache status memory. This is to insure that ownership rules are not violated and to determine whether ownership status must be updated for that location. If ownership data requires updating, then the memory controller must also write to the cache status memory. Each data memory access, thus, is always accompanied by a corresponding status memory access to read, and possibly to write, to the cache status memory. Because there is only a single set of address and control signals to the memory device, there is no way to access the data memory concurrently with the cache status memory. Instead, a cache status access must be executed prior to, or after, a data memory access. As a result, memory access times are effectively doubled in a shared memory environment.
Yet a further drawback to typical shared memory systems is their inability to accommodate multiple or various memory configurations. Multi-processor systems are employed for a variety of different types of tasks, some of which are unforeseen at the time of manufacture. Some tasks may be memory intensive, requiring vast amounts of memory for storing data or applications, while other tasks may be speed or space sensitive, where only minimal memory capacity is desired. Typical multi-processor systems, however, incorporate fixed designs with little ability for memory reconfiguration.
This is due, in part, to memory controllers which generate addressing, timing and control signals for the data and cache status memories. These memory controllers are typically designed for specific memory devices having a specified memory size and addressing scheme. Once a memory controller is chosen for incorporation into a memory system, the memory system is limited to employing only memory devices which are compatible with the provided memory controller.
A shared memory system, therefore, generally requires twice the memory capacity required for storing the data and software and twice the access time of conventional systems, yet does not provide sufficient memory reconfiguration capabilities. These drawbacks may, in some circumstances, outweigh the advantages of parallel or simultaneous processing.
What is needed, therefore, is an improved memory system where, in order to reduce access time, a data memory portion is concurrently accessed with a cache status memory portion and where, in order to reduce space requirements and costs, the cache status memory portion is significantly smaller than the data memory portion, and where, in order to provide greater flexibility, programmable control logic is provided, possibly within a memory controller, for concurrently accessing the data memory and the cache status memory, regardless of the size or configuration of the memories. | {
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Peroral delivery of therapeutics is generally considered to be the most popular method of drug delivery for patients since this route, in general, increases patient compliance, decreases the number of side effects associated with injections, and provides convenience for the user. Such an administration route is greatly favored for dosing chronically ill patients.
Carotenoids are a class of hydrocarbons consisting of isoprenoid units. The backbone of the molecule consists of conjugated carbon-carbon double and single bonds, and can also have pendant groups. Crocetin and trans sodium crocetinate (TSC) are known to increase the diffusivity of oxygen in aqueous solutions.
U.S. Pat. No. 6,060,511 relates to trans sodium crocetinate (TSC) and its uses. The patent covers various uses of TSC such as improving oxygen diffusivity and treatment of hemorrhagic shock.
U.S. patent application Ser. No. 10/647,132 relates to synthesis methods for making bipolar trans carotenoid salts (BTC) and methods of using them.
U.S. patent application Ser. No. 11/361,054 relates to improved BTC synthesis methods and novel uses of the BTC.
U.S. patent application Ser. No. 12/081,236 relates to the use of bipolar trans carotenoids as a pretreatment and in the treatment of peripheral vascular disease.
U.S. patent application Ser. No. 12/289,713 relates to a new class of therapeutics that enhance small molecule diffusion.
U.S. Provisional Application Ser. No. 61/213,575 relates to the use of diffusion enhancing compounds with thrombolytics.
A variety of bipolar trans carotenoids formulations have been disclosed. See commonly owned application U.S. patent application Ser. No. 10/647,132 and U.S. patent application Ser. No. 11/361,054. | {
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Methods and apparatus for aerating turf are shown and described.
The conception of a pair of tine shafts driven through a differential shaft in a turf aerator as taught in U.S. Pat. No. 6,708,773, which is hereby incorporated herein by reference, represented a major innovation in the turf field. In particular, the ability to operatively connect and clutch one or the other or both of the tine shafts, whether done mechanically, hydrostatically, or in other manners or combinations, allow the operator to make turns while the tines are still in contact with the turf. However, once turning was a possibility, operators desired further ability in directing the turf aerator during operation.
As an example, in an alternate approach by others to this major innovation, outer tine assemblies were rotatably mounted at the two end portions of a single driven shaft including inner tine assemblies secured to the single driven shaft intermediate the outer tine assemblies. Although increasing turning ability relative to conventional turf aerators existing prior to U.S. Pat. No. 6,708,773, this alternate approach did not have the turning ability achieved by the turf aerator of U.S. Pat. No. 6,708,773.
Further, during normal operation of the turf aerator, the tines need servicing such as the result of blockage and breakage. Such servicing was performed from underneath the conventional turf aerator which was often held in a tilted condition. Furthermore, replacement of tines was difficult to accomplish by the operator, and tine reel assemblies utilized were difficult and expensive to manufacture and assemble.
Likewise, to provide penetration of the tines into the turf, weights are removably attached to the sides of the chassis in conventional turf aerators. It can then be appreciated that such removable weights increased the overall mass which resulted in increased operator fatigue and apparatus wear as well as reduced maneuverability.
Additionally, conventional turf aerators utilized various arrangements to position transport wheels relative to the chassis to allow transport without tine engagement as well as to control the depth of tine penetration. However, such arrangements were relatively complicated in design increasing cost and maintenance as well as requiring tools for adjustment.
Thus, need for improvement in methods and apparatus for aerating exists in the field of turf management. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to television apparatus and, more particularly, is directed to a television apparatus of the type including a television receiver and a video tape recorder integrally incorporated therein.
2. Description of the Prior Art
It is known to provide a television receiver with a video tape recorder integrally incorporated in the cabinet of the television receiver which also houses or supports a speaker or speakers. Such arrangement provides a convenient and compact assembly. Moreover, with such assembly, a television signal received by a tuner of the television receiver is recordable in a tape cassette by the video tape recorder while the video information and audio information included in the television signal are respectively displayed by the display screen and reproduced by the speakers of the television receiver. Similarly, the video and audio information recorded in a tape cassette can be reproduced therefrom by the video tape recorder for display and reproduction by the display screen and speakers, respectively, of the television receiver.
However, when a television receiver has a video tape recorder incorporated therein, as described above, it is usually unavoidable that, as the level of the audio output of the speakers is increased, the cabinet, chassis, component parts and the like are made to vibrate at inherent resonant frequencies thereof which are included in the reproduced sound, and this may cause noise or distortions in the reproduced picture, particularly when a mechanical resonant vibration frequency of the video tape recorder is included in the reproduced sound during a recording operation. Such noise or distortion results from a harmful effect exerted on the transport of the tape by mechanical vibration of the video tape recorder during its recording operation, as when the video information and audio information of a television signal are being recorded simultaneously with the monitoring of the television signal by the television receiver and there is a high-level audio output from the speakers thereof which includes substantially a mechanical resonant vibration frequency of the video tape recorder. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates in general to digitally controlled oscillators. More particularly, the present invention relates to an offset (non-symmetrical) digitally controlled oscillator which is capable of functioning in a linear mode and is especially desirable for use in phase locked loop circuitry.
2. Description of the Prior Art
Various configurations of circuitry have previously been used in phase locked loop circuitry to generate the necessary output frequency. The first and most common configuration is the voltage controlled oscillator (VCO) as used in the analog phase locked loop. The input signal to the VCO is a time varying voltage and is converted by the VCO to a proportional frequency. The output of the VCO is fed back to an appropriate point as a reference signal. A typical VCO in this type of configuration includes a varactor, the impedance of the feedback network is changed and thus the resonant frequency of the oscillator is changed. The use of the varactor introduces slight non-linearity to the transfer function of the VCO.
Various other configurations employ the use of a symmetrical digitally controlled oscillator (DCO). In prior versions of DCO circuit implementation, frequency generation has been accomplished through the use of a divide by n, n-1 or n+1 symmetrical configuration. In this type of circuit, the center frequency is:
f.sub.c =f.sub.HS /n, where n is the high speed divide ratio. Frequencies greater than f.sub.c are generated by dividing f.sub.HS by n-1 and frequencies less than f.sub.c are generated by dividing f.sub.HS by n+1. In order to linearize the transfer function of this configuration, a ROM or other programmable device was used to distort the input to the DCO.
The present invention as claimed is intended to provide an offset digitally controlled oscillator which eliminates many of the prior art deficiencies which include the need to introduce predistortion into the input signal to the DCO. Many of the prior art implementations are not sufficiently reliable and are not sufficiently repeatable regarding their operation. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates to a coreless motor.
Recently, a coreless motor of the type in which a coreless rotor having a pancake coil on an insulating substrate in a one-layer or multi-layer fashion, has been developed. The rotor of this type is formed, for example, by printing a coil pattern, or attaching a coil pattern of electroconductive foil, onto a light-weight insulating coil such as synthetic resin etc. Since such coreless rotor is light in weight and small in inertial force, if it is used, for example, in a tape driving motor of a tape recorder calling for such features, a rise in the rotation of a capstan apindle during the starting of the motor as well as a rapid stopping of a tape in a desired position can be smoothly effected. However, if the center of gravity of the rotor is deviated due to, for example, the eccentricity of a rotor shaft, an irregular rotation of the rotor tends to occur to a great disadvantage. In order to compensate for such irregular rotation, an attempt is made to attach a balance weight on the rotor. In so doing, a clearance for the balance weight is provided between the rotor and a housing, thus making the housing bulkier.
An irregular rotation of the rotor often occurs due to, for example, a variation in input voltage to the motor. To avoid such disadvantage, a servo mechanism is provided by which the number of rotations of the rotor is controlled through its detection. The number of rotations of the rotor is normally detected by a permanent magnet mounted on the rotor and a detection coil mounted on that surface of the housing which oppositely faces the permanent magnet. This requires a spacing for such electrical parts or elements within the housing, resulting in a bulkier motor. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a method of removing an organic film adhered to a substrate, enabling the surface of an electronic device substrate or the like to be cleaned, and also relates to an organic film removal apparatus and a resist film removal reagent. In particular the invention relates to the removal of photoresist films used during the processing of semiconductor wafers or liquid crystal substrates. Furthermore, the invention also relates to the removal of organic contaminant films or fine particles from such substrates. In addition, the present invention can also be applied to the removal of more typical organic films such as oil films or paint films from a substrate.
2. Description of the Prior Art
The removal of photoresists used during the ultra fine processing of oxide films or polysilicon films typically employs a method wherein the substrate is immersed in a mixed solution of sulfuric acid (3 or 4 parts by volume) and hydrogen peroxide (1 part by volume) (known as piranha) and heated at 110 to 140xc2x0 C. for 10 to 20 minutes. In those cases in which a high concentration ion implantation has been performed using a resist mask, the resist itself degenerates and cannot be easily removed using a piranha solution, and consequently ashing with plasma excited oxygen is typically employed. Resists which have suffered surface degeneration following dry etching are also removed in this manner. However, if an entire photoresist is subjected to ashing, organic decomposition residues, fine particles and minute quantities of metal derived from the resist remain, and films of decomposed material also remain on the side walls of channels which have undergone processing. In addition, because the ashing process requires a high energy plasma, the surface of the wafer is also exposed to damage which could harm a semiconductor device. Consequently, ashing is typically performed so that a minute quantity of the resist film remains, and this residual resist is subsequently removed using either piranha treatment, or treatment with an organic solvent such as n-methylpyrolidone (NMP), dimethylsulfoxide (DMSO) or an amine in the case of a metal wiring film process.
Piranha treatment discharges large quantities of sulfuric acid, and similarly treatments which use organic solvents also consume large quantities of solvent, and consequently both types of treatment cause large environmental problems. As a result, resist removal using ozone water has recently been tested. The solubility of ozone in water increases as the temperature is lowered, and if a gas containing a high concentration of ozone (hereafter referred to as ozone gas) is used, then the solubility of ozone in cold water of approximately 0xc2x0 C. reaches 70 to 100 ppm. However, with this type of ozone water treatment, the stripping rate for a novolak resin based positive resist film used with i-line radiation, which is a widely used configuration in LSI production, is slow, at not more than 0.1 xcexcm/minute, meaning the treatment is not entirely practical. Recently, methods involving treatment with a combination of a high concentration ozone gas and water vapor, and methods involving treatment with a high concentration ozone water utilizing pressurized ozone have also been developed, but the stripping rates with these methods is still slow at approximately 1 xcexcm/minute, and in the case of a substrate comprising a metal wiring film of Cu, W or Mo or the like, damage to the film also becomes a problem.
Regardless of whether piranha treatment or organic solvent treatment is used, from a productivity perspective, the process involves the treatment of a plurality of wafer containing carriers which are inserted in a liquid contained within a cleaning vessel. In the former treatment, hydrogen peroxide decomposes forming water, and the solution gradually becomes diluted, requiring the addition of more hydrogen peroxide, although there is a limit to the amount of additional hydrogen peroxide that can be added. Accordingly, the usable lifespan of the chemical solution in the cleaning vessel is surprisingly short, and large volumes of sulfuric acid need to be discharged, resulting in considerable costs associated with environmental measures. In the case of the latter treatment, repeated use results in an accumulation of dissolved resist within the solvent, which leads to an increase in reverse contamination of the wafer and places a larger load on the rinse solution. Accordingly, the solvent within the cleaning vessel needs to be changed quite regularly. Certainly, neither treatment can be claimed to be economical.
Resists which have undergone strong dry etching or high concentration ion implantation and have suffered considerable degeneration are impossible to remove using conventional wet treatments, and these types of resists are currently removed using ashing methods. However as described above, ashing has a considerable number of associated problems, and also requires a subsequent wet treatment.
In a wet treatment using an organic solvent, metal impurities within the resist migrate into the treatment liquid, and as the treatment liquid is used repeatedly the concentration within the liquid of metal derived from the resist increases. If this metal is a metal with a larger oxide formation enthalpy than silicon, such as iron, zinc or aluminum, then there is a danger of substitution via Sixe2x80x94O linkages occurring at the resist removal surface, resulting in contamination of the surface.
Furthermore, resist removal using organic solvents is used almost exclusively in cases in which the substrate is a metal wiring film. Removal solvents with a strong stripping performance typically contain an amine, and if a rinse with pure water is performed immediately after treatment then strongly alkaline sections are generated, and there is a considerable danger of damage being caused to the metal film of the substrate. Accordingly, the treatment solvent is exchanged with isopropyl alcohol prior to rinsing with pure water, making increases in the organic solvent consumption unavoidable.
A photoresist stripping liquid composition formed from 4-methoxy-1-butanol, 3-methoxy-1-butanol or a mixture of 4-methoxy-1-butanol and 3-methoxy-1-butanol, together with propylene carbonate is disclosed in Japanese Patent Publication No. 2679618 (JP 2679618 B), although no mention is made of the use of only propylene carbonate, and similarly no mention is made of ozone use.
Furthermore, U.S. Pat. No. 5,690,747 discloses a method for removing a photoresist in an ultrasonically agitated solvent comprising (a) 40 to 50 vol % of an aprotic cyclic carbonate ester such as ethylene carbonate, (b) an aprotic polar compound such as ethylene diacetate and ethylene dibutyrate, as well as the solvents N-methyl-2-pyrrolidone and triethanolamine. In addition, the cleaning effect of ethylene carbonate and propylene carbonate on ink and the like has also been reported. However, there have been no reports regarding the use of only ethylene carbonate or propylene carbonate for photoresist removal, nor on their combined use with ozone.
An object of the present invention is to provide a method and an apparatus for effectively removing not only resists, but also other organic films such as oil films and paint films, which are capable of achieving an extremely rapid stripping rate of 20 xcexcm/minute for a typical resist film, and are also capable of removing even resist films which have undergone considerable degeneration as a result of ion implantation or the like at a satisfactorily productive stripping rate of several ttm/min, and which moreover do not damage the surface of the substrate beneath the film, do not suffer from the types of environmental problems described above, and are extremely economical.
A first aspect of the present invention provides a method for removing an organic film on a surface of a substrate, comprising:
bringing a treatment liquid comprising liquid ethylene carbonate, propylene carbonate, or both of them into contact with said substrate to remove said organic film, thereby allowing material constituting said organic film to migrate into said treatment liquid,
decomposing said material in said treatment liquid into low molecular weight material by ozone, thereby said ozone treated treatment liquid being regenerated as a treatment liquid, and
recycling the treatment liquid thus regenerated for treating another substrate.
A second aspect of the present invention provides a method for removing an organic film on a surface of a substrate, comprising:
bringing a treatment liquid containing ozone dissolved in a liquid comprising ethylene carbonate, propylene carbonate, or both of them into contact with said substrate with an organic film on a surface thereof to remove said organic film, wherein said organic film is dissolved said treatment liquid and decomposed into low molecular weight material, and
using the treatment liquid after removal of said organic film for treating another substrate.
In a preferred embodiment of the second aspect of the present invention, said treatment liquid after removal of said organic film is recycled as a treatment liquid as it is for treating another substrate.
In another preferred embodiment of the second aspect of the present invention, said treatment liquid after removal of said organic film is further subjected to treatment with ozone, and then recycled as a treatment liquid for treating another substrate.
A third aspect of the present invention provides an apparatus for removing an organic film from a surface of a substrate comprising:
(A) a treatment liquid delivery means for transporting a treatment liquid comprising liquid ethylene carbonate, propylene carbonate, or both thereof to a treatment area,
(B) a film contact means for bringing the treatment liquid into contact with the surface of said organic film of the substrate within the treatment area,
(C) a treatment liquid circulation means for recycling treatment liquid used and discharged from the treatment area back to said treatment area via one or more temporary storage means, and
(D) an ozone-containing gas contact means for bringing an ozone-containing gas into contact with the treatment liquid discharged from said treatment area within said treatment area and/or within at least one of said temporary storage means. | {
"pile_set_name": "USPTO Backgrounds"
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The traditional method of replication of antique wind instruments and similar objects takes a material and shapes it to the dimensions of the original object. Such objects are traditionally measured by calipers. Reamers and drills are created from the measurements and raw materials are fashioned into a replica of the object using these tools. This process requires a highly-trained craftsman, is very time-consuming and has the potential to damage the instrument being copied. Further, such a process introduces small, but potentially cumulative errors at each step of the replication process. All of this makes the process expensive and limits production.
The disclosure contained herein is in the general field of systems for detailed and sophisticated analysis of the structure, construction and materials of various objects, such as period instruments. Disclosed herein are methods for non-destructive analysis and replication of period musical instruments and parts using an x-ray microtomography device and additive manufacture methods. Although the discussion herein focuses on the non-destructive analysis and replication of period musical instruments, these methods are equally applicable to the non-destructive analysis and replication of almost any three-dimensional object. | {
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Dielectric materials have high polarizability and are able to store electrostatic energy through charge separation of electric charges of opposite sign. Typically, capacitors are composed of metal electrodes or plates that are separated by a layer of dielectric material. An applied potential difference is used to ‘charge’ the capacitor by transferring electric charge from one electrode to the other. High voltage capacitors typically exist in cylindrical sandwiching of dielectric material and metal foil electrode. The dielectric material must be capable of holding an electric field across the electrodes without discharging it. When the electrical field within a dielectric medium changes, the momentary delay in change of the dielectric permittivity is referred to as the dielectric relaxation.
Commonly, dielectric materials have included inorganics such as mica and ceramics, although these materials suffer from brittleness and other insufficiencies. As a consequence, the use of polymeric materials has been explored, including high-polymer films such as polypropylene, polycarbonates, and polyimides. Enticing properties of such compounds include, for example, transparency, ductility, and low weight. Further polycarbonates are amorphous, glassy, non-crystalline materials ideally suited to film formation necessary for wound film capacitors. However, these materials often suffer from low glass transition temperatures making them impractical for many applications. Additionally, each type of material is limited by the temperatures at which it is able to sustain its breakdown voltage, inherent ability to be processed, and inherent dielectric permittivity. Commercial polycarbonate (BPA-PC) itself has been utilized many years in capacitors; however, it is desirable to develop polycarbonates with superior dielectric properties for use in energy dense capacitors. The use of polymeric materials with substitutions to the polymer backbone has been explored. For example, bis[4′-(3-fluoro-4-hydroxyphenyl)-phenyl]propane (DiF TABPA) has fluorine substituted onto the benzene rings located within the polymer backbone. See Bendler et al., Electrical Properties of a Novel Fluorinated Polycarbonate, 48 EURO. POLYMER J. 830-840 (2012). However, such compounds were found to either lack sufficient dielectric permittivity or to suffer from dielectric loss at temperatures that were too high, i.e., the loss would occur to close to room temperature. Substitutions of tethered nitrile groups onto the polymer backbone have also been explored. For example, 4,4-bis(4-hydroxyphenyl)pentanenitrile homopolycarbonate (CN-PC) was prepared and tested. See Bendler et al., Dielectric Properties of Bisphenol A Polycarbonate and Its Tethered Nitrile Analogue, 46 MACROMOLECULES 4024-4033 (2013). It was found that tethered nitrile groups created an encumbrance in rotation, which prevented adequate dipole rotation. Further, it was found that the nitrile substitutions were unable to exert the calculated effect of their dipoles, owing to restricted rotation on account of their size. Additionally, losses were into the working range of the capacitor.
Accordingly, it is an objective of the claimed invention to develop monomeric bisphenols containing one or more fluoromethyl groups in order to enhance the compounds dielectric constant.
A further object of this invention is to develop compounds having enhanced dielectric constants and low temperature dielectric losses suitable for pulsed power and other capacitors.
Still a further object of this invention is to dielectric materials, including, for example capacitors, comprising polycarbonates of homopolymers, copolymers, terpolymers, analogs, and/or other derivatives of bisphenols substituted with one or more fluoromethyl group; wherein such dielectric materials possess enhanced dielectric properties. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a welding mask put on by a user during a welding process for protecting user's eyes and face, and more particularly to a welding mask employing a connecting structure of an LCD shielding screen, in which the LCD shielding screen is easily attached to and detached from a welding plane of the welding mask and the LCD shielding screen is safely connected to the welding plane.
2. Description of the Related Art
Generally, various welding operations generate several dangers, such as strong harmful rays and splashing of base metal onto a user's face due to momentary heat of a high temperature and resistance. Accordingly, it is well known that a welding mask for protecting user's eyes and face from the above dangers during welding is used.
As shown in FIG. 1, a welding mask comprises a welding plane 10 having a transparent window 12 formed through the front surface thereof for covering a user's whole face, a wearable band 20 put on by a user at his/her head and connected to the welding plane 10 using a rotary shaft 22 for rotating the welding plane 10 up and down at a designated angle, and an LCD shielding screen 30 installed in the rear of the transparent window 12 of the welding plane 10 for protecting user's eyes from harmful rays generated from a welding operation.
The LCD shielding screen 30 comprises an LCD panel installed in a case for allowing a user to look outside therethrough and shielding harmful rays, a control unit for detecting the harmful rays generated during welding to operate the LCD panel, and a power supply unit for supplying power to the LCD panel and the control unit.
Accordingly, the LCD shielding screen 30 contacts the rear surface of the transparent window 12 of the welding plane 10, as described above, and is simultaneously fixed to the welding plane 10 using bolts so that the LCD shielding screen 30 is not easily detached from the welding plane 10.
The above-mentioned connecting structure of the LCD shielding screen 30 to the welding plane 10 of the welding mask causes an inconvenience in replacing the LCD shielding screen 30 with a new one. That is, when the LCD shielding screen 30, which is damaged, needs to be replaced with a new one or the transparent window 12 of the welding plane 10, which is used for a long time, needs to be replaced with a new one, the LCD shielding screen 30 must be separated from the welding plane 10, thereby causing an inconvenience in loosening and fastening a plurality of the bolts. Accordingly, an improved connecting structure of an LCD shielding screen for a welding mask has been required. | {
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The present invention relates to a route guide, and in particular relates to a route guide between buildings or inside buildings, and a method of providing route guidance to a destination through the inside of the building. In further detail, the present invention relates to a technique for providing a route guide using building information modeling (BIM) data.
A navigation system is a system that supports movement to a destination by presenting to a user a route to a destination along with a map, when a user inputs a destination and a starting point if necessary. Navigation systems were first developed as automotive navigation systems, and then as personal navigation devices (PND).
In recent years, in conjunction with enhanced functionality of mobile terminals such as smart phones, mobile phone, tablet terminals, mobile game devices, and the like, communication type navigation systems that transmit maps and route guide information from an information distribution server (possibly a route search server) to the mobile terminal have become popular as navigation systems for pedestrians. With these communication type navigation systems, application software installed in the mobile terminal (hereinafter also simply referred to as “application”) provides navigation functions to the user of the mobile terminal in cooperation with an application related to navigation that is installed in the information distribution server.
For example, Google® Maps, Ekipedia, NAVITIME®, MapFan® eye, Docomo® DriveNet, and Its-mo Navi are known applications that provides navigation functions to the mobile terminal.
Google Maps provides an indoor map function (known as “Indoor Google Maps” in addition to maps, local (regional) search functions, and route and transfer guidance functions. Indoor Google Maps enables viewing of indoor maps of some commercial facilities such as airports, train stations, department stores, shopping centers, malls, and the like using Google Maps. Furthermore, Google is publishing “Google Maps Floor Plant Marker” application on the Internet. With “Google Maps Floor Plan Marker”, the application collects GPS, mobile base station, and Wi-Fi data and the like while the user walks around inside the building, and can enhance navigation precision based on this collected data.
Ekipedia provides barrier free transfer maps in addition to train route searching functions.
Navitime® provides a TOTALNAVI® function that searches and displays the optimal route from a starting point to a destination, as well as a GURUTTONAVI® function that also searches for an optimal route by setting a midpoint in addition to a destination and starting point. Navitime Japan which is the developer of Navitime uses Navitime and is participating in verification testing of barrier free route guidance (Refer to nonpatent literature 4).
MapFan® eye is an AR pedestrians route guide application where the direction of travel can be intuitively understood simply by pointing an iPhone® in the forward direction.
Japanese Unexamined Patent Application 2011-21971 discloses an indoor guidance system that includes a plurality of marker devices provided at predetermined positions in a building, and a portable user terminal that can wirelessly transfer data with the marker devices. (Paragraph 0009).
Japanese Unexamined Patent Application 2006-250792 discloses a route information control system in which route information is transferred and recorded between a plurality of position marking devices that are attached along the route and a terminal device carried by a pedestrian (claim 1).
In order to achieve appropriate route guidance even in an indoor environment (paragraph 0012), Japanese Unexamined Patent Application 2010-286271 discloses a route guiding device that stores information that identifies a plurality of rooms and map information that includes information that identifies the contact point that a person travels through between each room and the rooms adjacent to each room, ranking is applied to each combination of the plurality of rooms and the plurality of contact points, and information that identifies one or more guidance information distribution points that define the direction is stored, and at least one guidance photograph data is stored for each of the one or more guidance information distribution points (claim 1).
Japanese Unexamined Patent Application 2011-75402 discloses that a storage part of a navigation server provides facility information recording means that associates and records coordinates for each facility, a building ID for each building where the facility exists, and a floor ID of the floor of the building where the facility exists (claim 1).
Japanese Unexamined Patent Application 2011-145164 discloses a navigation device having a recording part that stores outdoor map data indicating the condition of outdoor space, facility data that includes facilities provided at the starting point and the destination, structured data that expresses the indoor space of the structure, network data that includes link information between a node and another node required for route searching, structure and facility corresponding data that includes the relationship between structures and the facility, and data corresponding to structures and notes that include the corresponding relationship between notes and structures (claim 1).
Japanese Unexamined Patent Application2000-97721 discloses an indoor movement control device for a traveler that detects position using an indoor PHS and antenna technology, displays a travel route from a current position to a destination of the traveler on a terminal carried by the traveler, and announces route information while controlling entry by introducing and distinguishing security distinguishing events based on the security level of the destination (paragraph 0001).
Japanese Unexamined Patent Application 2006-133903 discloses an integrated information service system that provides integrated information support indoors and outdoors (paragraph 0004).
Japanese Unexamined Patent Application 2006-017647 discloses a communication navigation system that can effectively search for routes across floors even in underground malls and inside buildings (paragraph 0025).
Japanese Unexamined Patent Application 2008-33043 discloses a map information distribution system that efficiently distributes indoor route guiding maps even to terminal devices with a small display screen and a relatively small transfer capacity such as a mobile phone or PDA or the like (paragraph 0013).
Japanese Unexamined Patent Application 2012-128779 discloses a virtual object display device that generates a virtual object in three-dimensional virtual space, and displays the virtual object to a viewer (paragraph 0001). | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a method and a device for dividing up a total amount of fuel, which is to be injected into a combustion chamber of a cylinder during a combustion cycle, into a plurality of injections, as well as a method and a device for dividing up a total amount of fuel, which is to be injected into a combustion chamber of a cylinder during a combustion cycle and includes a first amount of fuel, a second amount of fuel, and a third amount of fuel, into a first injection, a second injection, and a third injection of the combustion cycle of the cylinder.
In common-rail injection systems for internal combustion engines, a high-pressure pump is used to build up a pressure of up to 2000 bar in a pressure chamber, which contains the fuel to be injected and is referred to as the common rail. The common rail is connected to all of the injection devices of all engine cylinders. Metering valves, usually solenoid valves or piezoelectric systems, are used as injection devices, through which fuel is injected into the combustion chamber of the cylinder, when they are in the open state.
In contrast to direct-injection systems, in which a pressure must be built up anew for each combustion cycle or injection cycle of each cylinder, the pressure in the common rail of the common-rail injection system remains in a constant range, regardless of the combustion sequence.
Since this high-pressure is applied to all of the solenoid valves of all engine cylinders, the fuel can therefore be injected into the combustion chambers of the cylinders, by controlling the opening of the respective solenoid valve in a simple manner, i.e. by controlling a lift, an opening and/or closing time, and an opening and/or closing speed of the solenoid valve.
However, the high pressure in the combustion chamber, up to 160 bar, and the speed at which the pressure increases during combustion cause these direct-injection systems and common-rail injection systems to be very loud.
In order to reduce the noise emissions, pre-injection is implemented in common-rail systems. In this context, a small amount of fuel is injected into the combustion chamber of the cylinder and ignited up to a few milliseconds prior to the main injection. This preheats the combustion chamber and creates improved conditions in the combustion chamber for the main combustion during the main injection.
In this regard, DE 198 60 398 proposes the implementation of a pre-injection, a main injection, and/or a post-injection, which can be divided up into a plurality of pre-injections, main injections, and/or post-injections, respectively.
U.S. Pat. No. 5,402,760 describes a fuel-injection control device, which provides various control-current waveforms for a solenoid valve, in order to minimize the effects of residual magnetic flux in this valve.
However, the mutual dependence of the injection amount and the injection times causes the individual injections of a combustion cycle in the described injection systems to affect each other. This can result, for example, in injection amounts not adjusted to each other being injected in the respective injection occurrences of a combustion cycle, or in control starting points not adapted to the specific injection amounts being used for the individual injection occurrences. This results in irregular combustion, along with unacceptable pressure gradients in the engine, which in turn lead to an increase in the noise and pollutant emissions.
The present invention is based on the problem of reducing noise emissions and pollutant emissions of the internal combustion engine.
This problem is solved by the features specified in claims 1, and 7, 12, and 13.
The advantages attained by the features listed in claim 1 include, in particular, that the amount of fuel for the last of the three injections of a combustion cycle does not fall below a minimum value. In this manner, it is ensured that, during the third injection of the combustion, sufficient fuel is supplied for satisfactory combustion, and therefore, a sudden drop in the combustion intensity due to insufficient fuel supply is prevented in the third injection. This advantageously prevents a sudden fall in the magnitude of the torque of the cylinder in relation to the total torque of the internal combustion engine. Consequently, a smoother characteristic curve of the pressure gradient in the engine, i.e. a characteristic not having, for example, a sharp fall, is attained. This ensures reduced noise and pollutant emissions.
An advantageous refinement of the present invention is specified in claim 2. The refinement according to claim 2 advantageously allows the fuel amount to be exactly determined, since the third fuel amount is calculated by subtracting the ascertained, first fuel amount, which is to be injected into the combustion chamber of the cylinder during a first injection of the combustion cycle, from the total fuel amount that is to be injected into the combustion chamber of the cylinder during a combustion cycle. Since the third fuel amount is calculated by simple subtraction, this refinement allows the computational time for the individual fuel amounts to be minimized.
A further advantageous refinement of the present invention according to claim 1 is specified in claim 3. The refinement according to claim 3 advantageously prevents a double calculation of the fuel amounts, since the total fuel amount is initially calculated, then the first fuel amount, then a second fuel amount that is to be injected into the combustion chamber of the cylinder during a second injection of the combustion cycle, and then the third fuel amount is calculated as a function of the three previously determined quantities. Therefore, the first injection has priority over the second injection.
The advantages attained by the features of claim 7 include, in particular, that the first position for the first injection and the second position for the second injection are checked in light of first limiting values and second limiting values, before the injections are carried out. This ensures that the injections are executed in the correct position, so that the individual injection occurrences do not mutually affect each other in a disadvantageous manner.
Further advantageous developments of the present invention ensue from the dependent claims. | {
"pile_set_name": "USPTO Backgrounds"
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The goal of vegetable breeding is to combine various desirable traits in a single variety/hybrid. Such desirable traits may include greater yield, resistance to diseases, insects or other pests, tolerance to heat and drought, better agronomic quality, higher nutritional value, enhanced growth rate and improved fruit properties.
Breeding techniques take advantage of a plant's method of pollination. There are two general methods of pollination: a plant self-pollinates if pollen from one flower is transferred to the same or another flower of the same genotype. A plant cross-pollinates if pollen comes to it from a flower of a different genotype.
Plants that have been self-pollinated and selected for a uniform type over many generations become homozygous at almost all gene loci and produce a uniform population of true breeding progeny of homozygous plants. A cross between two such homozygous plants of different varieties produces a uniform population of hybrid plants that are heterozygous for many gene loci. The extent of heterozygosity in the hybrid is a function of the genetic distance between the parents. Conversely, a cross of two plants each heterozygous at a number of loci produces a segregating population of hybrid plants that differ genetically and are not uniform. The resulting non-uniformity makes performance unpredictable.
Tomato cultivars may be grouped by maturity, i.e. the time required from planting the seed to the stage where fruit harvest can occur. Standard maturity classifications include ‘early’, ‘midseason’ or late-maturing’. Another classification for tomatoes is the developmental timing of fruit set. ‘Determinant’ plants grow foliage, then transition into a reproductive phase of flower setting, pollination and fruit development. Consequently, determinant cultivars have a large proportion of the fruit ripen within a short time frame. Growers that harvest only once in a season favor determinant type cultivars. In contrast, ‘indeterminate’ types grow foliage, then enter a long phase where flower and fruit development proceed along with new foliar growth. Growers that harvest the same plants multiple times favor indeterminate type cultivars. In response to more recent consumer demands for dietary diversity, tomato breeders have developed a wider range of colors. In addition to expanding the range of red colored fruits, there are cultivars that produce fruits that are creamy white, lime green, yellow, green, golden, orange and purple. Additionally, there are multi-colored varieties exemplified by mainly red fruited varieties with green shoulders, and both striped- and variegated-colored fruit.
Tomato Grafting has been utilized worldwide in Asia and Europe for greenhouse and high tunnel production and is gaining popularity in the United States. In tomatoes, increases in fruit yield are likely due to increased water and nutrient uptake among vigorous rootstock genotypes. The main advantage of grafting is that rootstocks can be used which provide or enhance resistance against soil-borne diseases, especially when genetic or chemical approaches for disease management are not available or not sufficient. Thus, disease susceptible tomato scions can be grafted onto disease resistant rootstocks for tomato production. Apart from providing resistance against fungi and viruses, the use of grafting can also increase tolerance against different abiotic stresses such as cold/low temperature tolerance, drought tolerance, salinity tolerance, flooding/water tolerance and can have beneficial effects on e.g. growth, yield, nutrient uptake, plant vigor, fruit size and fruit quality. There are several methods for grafting tomatoes each with its own advantages and disadvantages. The most common methods are described in Davis et al. (2008), Critical Reviews in Plant Sciences Vol. 27, “Cucurbit Grafting”, page 50-74, and are amongst others the following:
1) Tongue Approach/Approach Graft,
2) Hole insertion/Terminal/Top Insertion Graft,
3) One Cotyledon/Slant/Splice/Tube Graft and
4) Cleft/Side Insertion Graft
The fruits of tomato plants which are more suitable for processing are generally red colored and have pink to red/crimson fruit flesh. | {
"pile_set_name": "USPTO Backgrounds"
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Wireless data communication systems for transmitting multimedia data, including audio, video and other data, are known. Recently, the explosion in the use of the Internet has dramatically increased multimedia data communication needs, including wireless data communication needs. Internet communications follow a packet-based protocol with wide variance in the size and frequency of packets. Generation of Internet packets generally occurs without regard to the actual physical networks that will carry the data. While this packet-based communication has great advantages, it presents numerous challenges for the efficient transmission of data over a particular physical network.
Known wireless data communication systems that support Internet access are typically a “retrofit” of Internet packets on top of an existing physical network. Unfortunately, these retrofits do not typically efficiently use bandwidth. And, performance is either sacrificed or uncontrolled, where performance includes parameters such as delay and jitter. Most existing systems over engineer the available bandwidth to accommodate a predefined maximum amount of traffic. Although this may be acceptable in wired networks, the limitations on wireless networks do not permit such a luxury. While all wireless packetized data presents some challenge, packetized audio and video streaming data is particularly challenging since the performance, namely, delay and jitter, may inhibit effective communications, in particular in the case of a two-way conversation.
Therefore, a need exists for a new paradigm in the communication of multimedia data over a wireless channel. | {
"pile_set_name": "USPTO Backgrounds"
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Imaging techniques play a key role in biomedical studies and clinical practice. Compared with other imaging modalities, optical methods possess several significant merits. Optical methods utilize non-ionizing and safe radiation to investigate tissue, and thus are especially suitable for screening and monitoring applications. Optical tools are also capable of providing various imaging contrasts, and therefore are versatile in visualizing different structures, physiological functions, and molecule-specific events. For example, blood strongly absorbs light; therefore, morphology of blood vasculature can be readily mapped by optical systems that exploit absorptions contrast. The difference in the absorption spectra of different hemoglobin molecules can be further exploited to evaluate an oxygen saturation level of blood. Also, blood flow can be quantified using optical frequency shifts of scattered light based on the Doppler effect. Further, when commercialized, optical systems can potentially be made compact, portable and inexpensive.
Most current optical imaging techniques can be classified into two groups. The first group, known as ballistic imaging, works in the ballistic regime. It includes early-photon imaging, confocal microscopy, and optical coherence tomography. These modalities rely on unscattered or singly backscattered photons, which are selectively collected using gating techniques based on time-of-flight, spatial collimation or coherence. Although exclusive use of ballistic photons assures high-resolution imaging, ballistic photons attenuate exponentially with penetration. As a result, imaging depth of ballistic imaging is limited to less than approximately 1.0 millimeters (mm) in highly scattering tissue, such as skin.
The second group works in a diffusive regime, and mainly includes diffuse optical tomography. Diffuse optical tomography measures diffused light reemitted from tissue through multiple source-detector pairs. An algorithm, based on a photon propagation model, is adopted to invert measurements to form a spatial map of tissue's optical properties. However, although use of diffused light allows diffuse optical tomography to visualize several centimeters deep inside turbid tissue, achieved spatial resolution is poor, typically about a fraction of a centimeter, as a result of the nature of photon diffusion.
As described above, development of optical imaging faces a major challenge, namely that turbid media, like biological tissue, strongly scatters light. Unlike X-ray photons, optical photons can penetrate approximately 1.0 mm (typical transport mean free path for biological tissue) into biological tissue, and still mostly maintain their original directions. This penetration range is called the ballistic regime. After traveling approximately 1.0 centimeters (cm) inside tissue, photons almost completely lose their memory of their original incidence direction after a large number of scattering events, and enter the so-called diffusive regime. The quasidiffusive regime (between approximately 1.0 mm and approximately 1.0 cm inside tissue) refers to the transition region between the two, where photons experience multiple scattering events and retain only a weak memory of their original directions. | {
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1. Field of Application
The present invention relates to a control system of an electrical generator of a vehicle, and in particular to an electrical generator control system whereby the production of voltage spikes in a supply voltage, resulting from disconnection of an electrical load, can be substantially suppressed.
2. Description of Prior Art
A motor vehicle is equipped with an electrical generator which is in general constituted as an alternator (e.g., 3-phase AC generator) that is driven by the vehicle engine, in combination with a rectifier circuit, to produce an unsmoothed DC output voltage. The electrical generator serves not only for charging the storage battery of the vehicle (referred to in the following simply as the battery) but also for supplying power to various types of electrical load. The level of output voltage of such an electrical generator, and hence the total value of output current that is supplied to the battery and the loads, is controlled through adjustment of the level of field current of the alternator, by varying the duty ratio of successive on/off switching of the field current. This control of the generator voltage is performed by a circuit generally referred to as the regulator.
Japanese patent publication No. 4-12639 describes such a prior art type of electrical generator control system, whereby when one of various electrical loads of that are supplied from the output of the electrical generator is disconnected, the magnitude of a resultant increase in the output voltage of the electrical generator is detected, and control is applied to lower that output voltage of and thereby reduce the level of generated current (by reducing the field current of the alternator) in accordance with the detected amount of voltage increase.
With such a prior art generator control method, a certain amount of delay will occur between the time point at which the electrical load is removed and the point at which control of generator output (reduction of the generated current level) becomes fully effective. Hence, a voltage spike that is of significant amplitude may occur at the time of load disconnection.
This is illustrated in FIG. 4, in which it is assumed that the level of current supplied by the electrical generator is reduced from 70 A to 40, when disconnection of a certain electrical load occurs at the time point t2. As shown, a voltage spike appears in the battery voltage (i.e., the output voltage of the electrical generator), and such voltage transients can have serious adverse effects upon the operation of various equipment of the vehicle, such as an ECU that performs overall control of the vehicle, equipment that controls the power steering system of the vehicle, etc.
In particular, if the level of current being supplied to the electrical load prior to its disconnection is high, and/or the battery is fully charged, or almost fully charged, then such a voltage spike will be large in amplitude. | {
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Devices for capturing and storing bodily fluid intravaginally are commercially available and known in the literature. Intravaginal tampons are the most common example of such devices. Commercially available tampons are generally compressed cylindrical masses of absorbent fibers that may be over-wrapped with an absorbent or nonabsorbent cover layer.
The tampon is inserted into the human vagina and retained there for a time for the purpose of capturing and storing intravaginal bodily fluids, most commonly menstrual fluid. As intravaginal bodily fluid contacts the tampon, it should be absorbed and retained by the absorbent material of the tampon. After a time, the tampon and its retained fluid is removed and disposed, and if necessary, another tampon is inserted.
A drawback often encountered with commercially available tampons is the tendency toward premature failure, which may be defined as bodily fluid leakage from the vagina while the tampon is in place, and before the tampon is completely saturated with the bodily fluid. The patent art typically describes a problem believed to occur that an unexpanded, compressed tampon is unable to immediately absorb fluid. Therefore, it presumes that premature leakage may occur when bodily fluid contacts a portion of the compressed tampon, and the fluid is not readily absorbed. The bodily fluid may bypass the tampon.
To overcome this problem of premature leakage, extra elements have been incorporated into a basic tampon to try to direct and control the flow of fluid toward the absorbent core.
For example, U.S. Pat. No. 4,212,301 (Johnson) discloses a unitary constructed digital tampon having a lower portion compressed preferably in the radial direction to form a rigid, rod-like element, which provides a central rigidified elongated core and an upper portion left substantially uncompressed. After insertion, the uncompressed portion may be manipulated to contact the vaginal wall to provide an immediate seal against side leakage. The uncompressed portion allows for high absorbent capacity immediately upon insertion. While this tampon may allow for a certain amount of protection from bypass leakage, the uncompressed portion may become saturated before the compressed portion has a chance to expand and become absorbent.
U.S. Pat. No. 6,358,235 (Osborn et al.) discloses a “hollow” bag-like tampon that may have an interior projection made from highly compressed absorbent material. The interior projection is preferably attached to the inside surface of the head of the tampon. The hollow tampon portion may include at least one pleat in the absorbent outer surface and is soft and conformable. The tampon is not pre-compressed to the point where the fibers temporarily “set” and re-expand upon the absorption of fluid. The absorbent portions of the tampon can saturate locally, which leads to bypass leakage.
U.S. Pat. No. 6,177,608 (Weinstrauch) discloses a tampon having nonwoven barrier strips which are outwardly spreadable from the tampon surface to reliably close the free spaces believed to exist within a vaginal cavity. The nonwoven barrier strips extend about the tampon in a circumferential direction at the surface or in a helical configuration about the tampon and purportedly conduct menstrual fluid toward the tampon surface. The nonwoven barrier strips are attached to the cover by means of gluing, heat sealing, needle punching, embossing or the like and form pleats. The nonwoven barrier strips are attached to the tampon blank and the blank is embossed, forming grooves extending in a longitudinal direction. While this tampon purports to direct fluid to the core, it attempts to achieve this by forming pockets of absorbent nonwoven fabric. In order to function, it appears that these pockets would have to be opened during use to allow fluid to enter. However, based upon current understandings of vaginal pressures, it is not understood how the described structure could form such an opened volume.
U.S. Pat. No. 6,206,867 (Osborn) suggests that a desirable tampon has at least a portion of which is dry expanding to cover a significant portion of the vaginal interior immediately upon deployment. To address this desire, it discloses a tampon having a compressed central absorbent core having at least one flexible panel attached along a portion of the side surface of the core. The flexible panel appears to provide the “dry-expanding” function, and it extends outwardly from the core away from the point of attachment. The flexible panel contacts the inner surfaces of the vagina when the tampon is in place and purportedly directs fluid toward the absorbent core. The flexible panel is typically attached to the pledget prior to compression of the pledget to form the absorbent core and remains in an uncompressed state.
U.S. Pat. No. 5,817,077 (Foley et al.) discloses a method of preserving natural moisture of vaginal epithelial tissue while a using a tampon where the tampon has an initial capillary suction pressure at the outer surface of less than about 40 mm Hg. This allows the tampon to absorb vaginal secretions without substantially drying the vaginal epithelial tissue. The multiple cover layers can be used to increase the thickness of the cover material. While this represents a significant advancement in the art, this invention does not address by-pass leakage.
Additionally, U.S. Pat. No. 5,545,155 (Hseih et al.) discloses an external absorbent article that has a set of plates separated by spacer elements. The plates may be treated to affect wettability so that fluid will flow easily across the surface. Extending through the upper plate is a plurality of openings, which allow fluid to flow with little restriction into the space between the upper and lower plates. When the fluid flows downward in the z-direction from the upper plate to the lower plate, it will then flow laterally in the x- and y-directions. Therefore, this external absorbent article can contain fluid gushes, but it does not appear to address the problems relating in particular to intravaginal devices, such as a tampon.
While the prior art is replete with examples of sanitary protection articles that capture bodily fluids both externally and intravaginally, these examples do not overcome the problem of premature failure often identified as by-pass leakage that commonly occurs while using internal sanitary protection devices. Many solutions to this problem have involved increasing the rate of expansion of a highly compressed absorbent article.
Surprisingly, we have found a novel way to address the problem of premature failure. This invention is not dependent on the expansion of the compressed absorbent but rather directing the fluid by the use of inter-plate capillary action. In our invention, we minimize local saturation of the fluid storage element. Our invention also is effective for handling highly viscous menstrual fluid. | {
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The present invention provides an improved needle-guard assembly for medical devices which are used, for example, in the administration of drugs or for the withdrawal of blood. More particularly, the invention relates to needle-bearing medical appliances, such as hypodermic syringes, i.v. catheter placement units, phlebotomy (blood-collecting) apparatus and the like, furnished with retractable, tubular shields designed to protect the needle portion of such devices prior to use, and to be locked around the needle after use in order to prevent injury from accidental contact.
Needle-bearing devices which are utilized for the subcutaneous or intramuscular injection of medicaments, or for insertion into a blood vessel are generally manufactured in disposable form so as to reduce the risk of patient infection. One group which remains at risk in dealing with such devices are health care professionals and housekeeping personnel who must handle these skin-puncturing devices after they have been used. Contaminated needles present a substantial health hazard and can result in transmission of a number of potentially life-threatening diseases.
That this problem has been recognized in the art is evidenced by the number of patents which have issued directed to apparatus for shielding needles after use, for example, U.S. Pat. Nos. 3,890,971, 4,139,009, 4,507,117 and 4,592,744. Of particular interest to the background of the present invention are three United States patents which employ retractable, tubular shields adapted to surround the needle portion of a disposable hypodermic syringe after it has been used--U.S. Pat. Nos. 4,425,120, 4,573,976 and 4,631,057.
U.S. Pat. No. 4,425,120 (Sampson et al) describes a hypodermic syringe having a tubular shield which is designed to be locked in either a needle-shielding position or a retracted position. The shield is held in either of these two positions by means of upstanding pins on the syringe body which are adapted to cooperate with tracks formed in the shield. Locking is accomplished by rotating the shield so that the pin is held by an offset at the terminus of the track.
A later Sampson et al patent, U.S. Pat. No. 4,573,976, depicts a syringe having a tubular shield equipped with an upstanding catch which is designed to hold the shield in either a needle-covering or a needle-exposed position. The device shown in this patent is said to be an improvement over the apparatus shown in the patentees' earlier U.S. Pat. No. 4,425,120 patent in that locking and unlocking can be accomplished without rotational movement of the shield.
U.S. Pat. No. 4,631,057 illustrates a third injury-preventing adaptation which permits movement of a tubular guard on a syringe body between needle-covering and needle-exposing positions. The guard is held in either of these positions by means of a collar located adjacent the distal end of the syringe barrel. The collar has circumferential indentations which are adapted to cooperate with projections on the interior of the tubular guard. This design permits easy disengagement of the guard from the latched position when the guard is in the retracted (needle-exposed) position. However, when the guard is in the extended (needle-covering) position, the shield is held in a substantially permanent locked condition. Prior to being used to dispense a liquid medication, a separate shield is required to cover the needle. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to cyanoacrylate tissue adhesives, and more particularly, to bioabsorbable cyanoacrylate tissue adhesive compositions and to methods for making and using these compositions. The compositions are useful in medical applications, including, but not limited to, wound and surgical incision closure, medical device fixation, sealants and void fillers, embolic agents and other general medical applications.
2. Description of the Background
Surgical incisions and wounds may be closed by three general methods, suturing, stapling and adhesive bonding.
U.S. Pat. No. 5,578,046 notes that sutures are bioabsorbable when the material that they are made from is capable of being broken down into smaller constituents, which can be metabolized and excreted by the living organism. Such materials are useful for temporarily holding tissues in a desired position during healing and are absorbed by the organism after a period of time. U.S. Pat. No. 5,578,046 as well as the patents and literature in turn referenced by U.S. Pat. No. 5,578,046 are incorporated herein by reference.
Wound suturing has the advantage of producing bioabsorbable, non-toxic degradation products. However, it also has disadvantages. Suturing requires time and skill. It causes additional trauma to the tissue by piercing and does not provide a hermetic closure.
Cyanoacrylates posses the unique property to bond living tissue. They have been widely and successfully tested for closing wounds and incisions, especially in cases where suturing does not provide satisfactory results. See Lijoi A. et al, "Subacute left ventricular free wall rupture complicating acute myocardial infarction. Successful surgical repair with a sutureless technique", J. Cardiovascular Surgery, 1996 December, 37(6), 627-630; Tebala G. D. et al, "The use of cyanoacrylate tissue adhesive in high-risk intestinal anastomoses", Surgery Today, 1995, 25 (12), 1069-72 and Zaki I. et al, "Split skin grafting on severely damaged skin. A technique using absorbable tissue adhesive", J. of Dermatologic Surgery and Oncology, 1994 December, 20(12), 827-9.
Cyanoacrylate tissue adhesives have the following advantages over suturing: they save time; they can bond difficult to suture tissues; they can provide a hermetic closure; they have hemostatic action; they produce better cosmetic results; and they may be indispensable in emergencies.
A major disadvantage of cyanoacrylate adhesives is that one of the degradation products is formaldehyde, which is toxic to the surrounding tissues (see Pani K. C. et al, "The degradation of n-butyl alpha-cyanoacrylate tissue adhesive. II.", Surgery, 1968 March, 63(3), 481-9). For this reason, cyanoacrylates have not found favor with the FDA for internal tissue closure. Only topical skin closure applications have been FDA approved.
Other disadvantages of cyanoacrylate tissue adhesives are their runniness (low viscosity) in uncured form and stiffness when cured. | {
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Polyester resins are used in a wide variety of applications such as coating materials, adhesives and films. Polyester resins in such applications need to exhibit excellent solubility in generic solvents.
Also, polyester resins made of biomass-derived monomers have been studied to alleviate global warming concerns.
For example, isosorbide is a dihydric alcohol, and is used as a biomass-derived monomer for forming a copolymerized polyester resin described in Patent Literature 1. The obtained polyester resin is soluble in generic solvents and is used in coating materials, adhesives and the like. | {
"pile_set_name": "USPTO Backgrounds"
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A general metal-oxide-semiconductor field-effect transistor (MOSFET) comprises a conductive electrode material formed over a gate dielectric (e.g., silicon oxide), which in turn overlies a semiconductor substrate (e.g., single-crystal semiconductor substrate). The electrode typically includes doped polysilicon, which entails many advantages as a gate electrode, and the underlying gate dielectric of today's commercial integrated circuits is typically a silicon dioxide layer grown out of the substrate.
The gate electrode material may also function as an interconnect. For example, dynamic random access memory (DRAM) word lines may be etched from a polysilicon layer deposited for the gates (often referred to in the industry as "poly-1"). Unfortunately, polysilicon resistivity is considerably higher than that of aluminum or other metals. Additionally, efforts to increase circuit density by scaling down device dimensions lead to polysilicon lines of decreasing width, leaving a small cross-sectional line area through which to conduct current. High polysilicon resistivity combined with small line width results in a high overall interconnect resistance, entailing greater power consumption, long propagation delays and slower access speeds. As integrated circuits are scaled down, access speed becomes a critical issue, so methods of reducing gate/interconnect resistivity are required.
In pursuit of lower overall gate resistance, highly conductive layers (e.g., metal, metal silicide, and/or metal nitride) have been implemented over the gate polysilicon, thus lowering the overall resistivity of the interconnect lines while retaining the gate integrity provided by polysilicon. For example, a layer of tungsten silicide or tungsten nitride may overlie the polysilicon, and another metal layer such as tungsten may overlie the silicide or nitride layer to further boost conductivity. Alternatively, a metal layer may also be deposited directly over the polysilicon, without the intervening metal silicide, depending upon stress and adhesion factors.
FIG. 1 illustrates a typical gate stack 10, comprising a metal layer 12 (e.g., tungsten), a metallic interlayer 14 (e.g., tungsten silicide), and a doped polysilicon layer 16, all overlying a gate oxide 18 which has been grown out of a silicon substrate 20. The interlayer 14 can comprise a metal silicide or metal nitride layer, or can be omitted altogether. An insulating cap layer (not shown) can also be formed at this stage.
After the layers that make up the gate stack 10 have been formed, gate structures are patterned in accordance with an integrated circuit design (e.g., a dynamic random access memory, or DRAM, array). FIG. 2 illustrates the result of patterning. After a resist mask 24 is formed by standard photolithographic processes, the stack 10 must then be etched through, thus producing a gate electrode 26 formed of the patterned polysilicon 28, silicide 30 and metal 32 straps, as shown. In general, plasma etches are utilized to create vertical profiles for the gate structures 26, although the particulars may vary depending upon the stack materials. The polysilicon layer 16 (FIG. 1), which is etched last of the stack materials, is usually etched by fluorine- or chlorine-based plasmas.
In either case, the plasma etch tends to cause considerable damage to the gate oxide 18 immediately subjacent the polysilicon layer 16 (FIG. 1). Such damage may result regardless of efforts to optimize etch selectivity and optical end point measurement techniques. FIG. 3 illustrates a closer view of the gate electrode 26 and physical damage (thinning) resulting from gate oxide 18 exposure to the plasma etch. It should be understood that damage to the chemical integrity of the gate oxide 18 also takes place as a result of photon-assisted and other damage during the ion bombardment generally utilized for anisotropic etching. The etch damage may also extend to the underlying silicon substrate.
A high quality gate insulator is required for reliable operation of the MOSFET device and of the circuit employing the MOSFET. Susceptibility to hot carrier effects and consequent charge trapping, high defect densities, silicon-oxide interface states, pinholes and oxide thinning can all cause punchthrough or tunneling current leakage. In turn, junction leakage results in increased threshold voltage and unreliable circuit operation. Damage to the gate oxide 18 caused by plasma etching may induce many of these problems, particularly at or near corners 35 of the gate 26. Aside from the illustrated physical thinning, plasma etching tends to damage oxide bonds, creating charge trap sites. Such structural damage extends laterally under the gate corners 35 as well as over adjacent source/drain regions. This damage must be repaired to improve the quality and life expectancy of the gate oxide 18. One common manner of repair is by a source/drain reoxidation step, a high temperature step performed in an oxygen environment.
Referring to FIG. 4, this reoxidation can involve wet oxidation at temperatures above 900.degree. C. for a relatively long period (e.g., up to 30 minutes). During this process, the oxide under the gate corners 35 is thickened and corners 35 of the polysilicon gate 28 are rounded. Small bird's beak structures 40 at the thickened corners reduce lateral electric field strength in active areas adjacent the gate 28, thereby reducing hot electron injection through the reoxidized gate oxide 38 during transistor operation.
Unfortunately, conditions during source/drain reoxidation also result in oxidation of exposed gate materials. Thus, for the illustrated example, a layer of tungsten oxide (WO.sub.x) 42 readily forms around tungsten metal straps 32. Similarly, oxides 44 such as tungsten oxide (WO.sub.x) and silicon dioxide (SiO.sub.2) grow out of the metallic interlayer strap 30.
The longer the reoxidation process and the higher the temperature, the more metal, metal nitride and/or silicide are consumed. The oxides 42, 44 formed in consumption of the metal in straps 30, 32 are insulating and so unable to contribute to word line conductivity. Thus, overall resistance can be radically increased by the source/drain reoxidation. Some metals, such as tungsten, are so readily oxidized that overall resistance is increased beyond tolerable levels, rendering such metals impractical for use in gate materials.
Accordingly, a need exists for gate fabrication processes and structures which permit low overall resistance at the gate level while maintaining high quality gate oxide composition. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates generally to a mobile terminal, and in particular, to a method of easily inputting icons that represent emotions (emoticons) of a user.
2. Description of the Related Art
In addition to telephone calls, a mobile terminal can provide a variety of additional functions such as an SMS (Short Message Service). The SMS enables short text messages to be exchanged between terminals (or computers) regardless of whether the terminal of the other party is busy or not. The relatively high cost of voice calls makes the SMS cost-effective enough to substitute for the voice calls. A user inputs a text message using the keys of the keypad on the terminal and transmits it via the SMS.
The SMS, however, limits a Korean text message to 40 characters, as well as limits the text message in other languages. Moreover only a few specific small keys are used to input the text message. Therefore, great amounts of time and effort are needed to input even a short message and often the short message becomes an abbreviation of what a user intends to express in the first place.
In an attempt to solve this problem, a mobile terminal may provide a variety of special characters along with the standard characters and digits. The characters and digits would vary with the programmed language, e.g., Korean, English, etc. FIG. 1 illustrates input modes supported by the conventional mobile terminal. As shown in FIG. 1, the mobile terminal displays available characters/digits in each input mode.
The illustrated mobile terminal of FIG. 1 also has a shortcoming in that a user must input a special character in a very complicated procedure (i.e., mode conversion, entry of an intended special character, input of key [CONFIRM], and etc.). Therefore, the conventional mobile terminal has limitations in the input of characters or symbols which can readily represent the emotions of a user in the form of an icon. | {
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Plant viruses are a continuing problem in the agricultural industry. Viral infection in plants causes a variety of undesirable effects including stunted growth, altered morphology, reduced yield, diminished quality and increased susceptibility to damage by other pests. The use of chemicals to control viruses is not always desirable and the use of biological agents, e.g. infection of plants with an attenuated strain of a virus, has not been always effective or desirable.
Damage to plants by insects is also a significant problem in agriculture. Crop yield can be significantly decreased and crop quality can be compromised if infested with insects. Control of insects can be obtained by insecticides, introduction of natural predators of the insect pest, crop rotation, or by genetic modification of plants to express an insect specific toxin.
Scientists have recently developed means to produce virus resistant plants using genetic engineering techniques. Such an approach is advantageous in that the means for providing the protection is incorporated in the plant itself and can be passed to its progeny. Most prominently, incorporation of a gene encoding the capsid protein (coat protein) of a plant virus in a plant has conferred resistance to the virus and related viruses. (Beachy et al. 1990). Even though coat-protein mediated viral resistance has proved to be useful in a variety of situations, it may not always be the most effective or most desirable means for providing viral resistance. In such instances, it would be advantageous to have other methods for conferring viral resistance in plants that also incorporate the advantages of a genetic engineering approach.
It has been suggested that pokeweed antiviral protein, an enzyme that is naturally expressed in pokeweed, functions as an antiviral defense mechanism in such plant. (Ready et al. 1986). This protein is one of a family of ribosome inhibiting proteins which inhibit translation by inactivating ribosomes. These proteins are potent ribosome inhibitors and are known to inactivate both homologous and heterologous plant ribosomes. (Schonfelder et al. 1990). Pokeweed antiviral protein is known to inhibit viral infection if applied exogenously to a plant surface or placed in direct contact with a virus. (Irwin et al. 1980; Tomlinson et al. 1974; Wyatt et al. 1969). Despite the antiviral function suggested for pokeweed antiviral protein in pokeweed and its exogenous effect, the pokeweed plant is itself still susceptible to infection by a variety of plant viruses including some potyviruses e.g. watermelon mosaic virus II and some potexviruses e.g. Hydrangea ringspot virus. (Klinkowski 1977) Therefore, the extent to which this protein is capable of providing protection against viral infection and which viruses it is capable of protecting against when expressed in planta was not known. This is especially true with respect to the expression of the protein in plants other than pokeweed. Furthermore, in pokeweed, the protein is found primarily sequestered in the cell walls and does not significantly inhibit the normal translation activities of the cell. (Ready et al. 1986) Whether pokeweed antiviral protein could be expressed in a plant other than pokeweed and not interrupt the normal translation activities of that plant was not known. | {
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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 S and 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 MOM-ET, the operation of an BEET 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:
I D = β ( V GS - V TH - 1 2 V DS ) V DS , ( 1 ) where 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 ) , ( 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 ) ( 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 ∅ F , ( 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 work functions 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 , ( 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 workfunction (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+ (6)AOH2+⇄AOH+HS+ (7)where A denotes an exemplary metal, HS+ represents a proton in the analyte solution 74. Eq. (6) describes proton donation by a surface group, and Eq. (7) describes proton acceptance by a surface group. It should be appreciated that the reactions given in Eqs. (6) and (7) 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+ (7b)wherein Eq. (7b) describes another proton acceptance equilibrium reaction. For purposes of the present discussion however, again only the proton donation and acceptance reactions given in Eqs. (6) and (7) 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 Eq. (6)) and Kb (for the reaction of Eq. (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, (8)where 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 int , ( 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 Ψ0 according to:σ0=cdlΨ0=−σdl (10)where 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 ( 11 ) Where k is the dielectric constant ε/ε0 (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 I ( 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 = 1 2 ∑ s z s 2 c s , ( 13 ) Where zs is the charge number of ionic species s and cs is the molar concentration of ionic species s. Accordingly, from Eqs. (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 Ψ0 as a parameter:
( pH s - pH B ) = q Ψ 0 kT ( 14 ) From Eqs. (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:
Δ Ψ 0 Δ pH = - 2.3 kT q α , ( 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 βint as discussed above in connection with Eq. (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., a is maximized by a large βint). From Eq. (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 Eqs. (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 Eq. (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 pHpze. With reference again to Eqs. (8) and (9), like the intrinsic buffering capacity βint, pHpze 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 pzc ) Δ Ψ 0 Δ pH . ( 16 ) Table 1 below lists various metal oxides and metal nitrides and their corresponding points of zero charge (pHpze), pH sensitivities (ΔVTH), and theoretical maximum surface potential at a pH of 9:
TABLE 1ΔVTHTheoretical Ψ0MetalOxide/NitridepHpzc(mV/pH)(mV) @ pH = 9AlAl2O39.254.5−11(35° C.)ZrZrO25.150150TiTiO25.557.4-62.3201(32° C.,pH 3-11)TaTa2O52.9, 2.862.87384(35° C.)SiSi3N44.6, 6-756.94251(25° C.)SiSiO22.143297MoMoO31.8-2.148-59396HfHfO27-4-7.650-5881.2WWO20.3, 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 8, 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 Eq. (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:
Δ Ψ 0 = Ψ 1 - Ψ 2 = σ 0 C d L 1 - σ 0 C d L 2 = Ψ 1 ( 1 - C d L 1 C d L 2 ) , ( 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 Eqs. (6) and (7) for metal oxides, and also Eq. (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 Eqs. (6), (7), and (7a) 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 Eq. (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:Ψ0(t)=ΔΨ0e−1/τ, (18)where the exponential function essentially represents the change in surface charge density as a function of time. In Eq. (16), the time constant τ is both a function of the bulk pH and material parameters of the passivation layer, according to:τ=τ0×10pH/2, (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 τ given by Eq. (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, 8: 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, 8: 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 8: 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 Mil grew 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 MOM-ET of the transmission gate is indicated as S11P and then—channel MOSFET is indicated as S1IN. 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 at. 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 PET 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 then-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 BEET, 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 ach 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 Barak, “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. Chern., 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. IV-169 to IV-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: Che_mical, 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. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates generally to the field of implant dentistry, and in particular to a new and useful pick-up implant abutment.
Impression copings are used to register the position of a dental implant placed into a patient's jaw. Two types of impression copings are used for implant level indexing.
The first type of impression coping is called a transfer coping which remains on an implant after the impression material is removed from the mouth. It is then removed from the implant, attached to the implant analog and inserted back into the impression. This technique is called the “closed tray method.” There are several factors which influence the accuracy of the closed tray method.
One factor is that it is impossible to machine the implant engaging parts of the impression coping and the implant abutment to be the same. A second factor is that it is impossible to machine the abutment engaging parts of the implant analog and the implant to be the same. Thirdly, some degree of impression material distortion always occurs during removal and re-insertion of the coping into the hardened impression material. This prevents accurate seating of the coping inside the impression.
A fourth factor is due to manufacturing tolerances. It is impossible to mate the implant analog with the implant abutment in exactly the same position as will be done with the implant and implant abutment later in the patient's mouth. A fifth factor is due to severe distortion of the impression material that occurs upon removal of the impression tray when multiple angulated implants are present.
The second type of implant impression or indexing is called the “open tray method” which eliminates the third and fifth factors. Impression coping used in this method is called pick-up coping, since it stays inside the impression material after the impression is removed from the mouth. The use of an elongated fastener and the hole made in the impression tray provide the means to disengage the coping from the implant and allow the removal of the impression from patient's mouth. The coping remains inside the impression material.
Though more accurate than the closed tray method, the open tray method still does not solve the three other problems noted above.
There is a need for a new abutment and method for taking an implant level impression which would eliminate the negative effect of size discrepancy between implant and implant analog, abutment and abutment analog and would also have the benefits of an open tray impression method.
The use of pick-up or transfer copings can be especially detrimental with locking taper implants (an example is described in the inventors co-pending international patent application PCT/US2007/074847 filed Jul. 31, 2007, and his U.S. patent application Ser. Nos. 11/615,131 filed Dec. 22, 2006, and 12/092,900 filed May 7, 2008) due to the sliding nature of the mating components. Discrepancies in diameter between the internal locking taper bore of the impression coping and the locking taper bore of the abutment will be multiplied several times due to sliding nature of the locking taper connection. A difference of only 6 microns will lead to a 100 microns difference in a vertical dimension (distance between the abutment or the impression coping, and the implant shoulder) between the impression coping/implant assembly and abutment/implant assembly. Current machining tolerances are much greater than 6 microns. If conventional impression methods are used, the discrepancy can be as high as 0.3 mm.
U.S. Pat. No. 5,106,300 to Voitik teaches the use of impression coping that is attached to the implant abutment and is picked up together with the abutment in the impression tray during an impression taking step. The open tray impression method is advocated by the inventor. Although more accurate then other described methods, this method also presents multiple challenges. Impression coping has to be used; impression coping has to be stocked in different sizes for abutments of different diameters and lengths; impression coping has to be properly attached to the abutment; and impression coping can separate from the abutment during impression removal because the fastener connecting the impression coping to the abutment and the implant has to be removed.
Known locking taper connection systems use conventional impression methods which produce inaccurate and unpredictable results.
An implant known as the Nobel Active external, was introduced in 2007 by Nobel Biocare AB, of Göteborg, Sweden, the largest implant manufacturer in the world. It has a 3 degree locking taper post and an indexing element in the form of a hex positioned on its end. The mating abutment has an internal 3 degree tapered bore and an internal indexing hex. The manufacturer realized that the use of impression coping would not yield an accurate result, so the standard crown and bridge impression method was advocated. The abutment is prepared by the dentist, tapped over the implant and an impression of the abutment is then taken and is sent to the laboratory for prosthesis fabrication. It is universally accepted that the use of implant level impression coping is much preferred in implant dentistry over the standard crown and bridge method.
Impladent Ltd. of Holliswood, N.Y., is an external locking taper implant manufacturer that also relies on the standard crown and bridge impression method.
The Bicon implant system (from Bicon Dental Implants of Boston, Mass.) uses implants having an internal locking taper bore and abutments with an external locking taper post. Bicon introduced the use of a plastic impression post which is tapped into the bore of the implant and is picked up by the impression material. The implant analog is than tapped over the post, and the abutment is tapped into the implant analog. During the prosthesis delivery appointment the abutment is tapped into the implant while the custom made acrylic jig restricts the rotational movement of the abutment. Many factors make accurate indexing impossible, however, the most critical ones being the inability of the operator to control tapping force and the difference in diameter between the implant analog and the implant, which affects the vertical positioning of the abutment. The abutment may seat more or less into the implant well, up to 0.1-0.2 mm, when compared to the implant analog.
It has been shown that accurate (i.e. within 0-10 microns range) repeated vertical connection between locking taper abutments and implants can only be achieved if:
1) the same abutment is mated with the same implant; and
2) the same amount of force is applied to activate the locking taper connection.
Accordingly a need remains for an improved pick-up implant abutment and the new method of implant position indexing that avoid the problems of the prior art. | {
"pile_set_name": "USPTO Backgrounds"
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Electrocardiography provides a set of standardized tests that are used for diagnosing abnormalities in the heart function of a patient. The standardized measurements record the potentials between various standard locations on the patient's body by placing electrodes in contact with the standard locations on the patient's body and recording potentials at the standard locations as a function of time. Most physicians are trained to read these graphs, which are often referred to as traces, as part of regular checkups or when a patient is exhibiting symptoms that may be caused by an underlying heart problem.
The standard twelve leads in an ECG test are divided into two groups, referred to as the standard leads and the precordial leads. The leads are generated by connecting ten electrodes to the patient's body and measuring the potentials between various ones of the leads or combinations of the leads as a function of time. In a clinical setting, the electrodes have adhesive pads for attaching the electrodes to the patient's body on the hands, feet, and six locations on the patient's chest, and the test is administered by a trained professional.
Unfortunately, the patient is often away from the clinical setting when a cardiovascular event is suspected. There are basically two solutions to this problem. The first involves connecting the electrodes to the appropriate locations on the patient's body adhesively and providing the patient with a portable unit that records the ECG traces. This type of solution generates traces that are essentially the same as those generated in the clinical setting; however, wearing the electrodes over a significant period of time presents numerous challenges if the patient also wishes to pursue a normal life.
The second solution involves providing the patient with a handheld unit that the patient uses to record various traces by holding the unit in the patient's hands and touching electrodes on the outside of the unit to various locations on the patient's body during the recording of the signals. Numerous devices have been proposed in which the handheld unit includes either three or four electrodes on the outer surface of the unit which the patient holds such that either one or both hands touch the electrodes while the patient places the remaining electrode at various points on the patient's body that are determined by the specific test or group of tests that are to recorded.
While these handheld devices allow the patient to perform one or more tests without having to affix electrodes adhesively to the patient's body, the resulting tests are not always a good approximation to the standard tests and present challenges when attempting to diagnose the patient based on these tests; however, even in the case of non-standard tests, these devices can be used to provide data on whether or not the patient's heart function has changed from the last tests performed with the handheld device.
All of these devices require the patient to maintain the electrical connection between the patient's skin and the electrodes on the handheld device for a period of seconds while the potentials on the electrodes are recorded. If the device loses contact between an electrode and the patient's skin, an abnormal recording will result. Since the patient is typically not a trained medical technician operating in a clinical setting, guaranteeing that the required pressure is applied between the patient's body and the electrodes in question presents significant challenges. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to a novel electrical insulating oil composition. More particularly, the invention relates to an electrical insulating oil composition which comprises compounds having biphenyl skeletons and is characterized in that the composition is excellent in low temperature characteristics and suitable for use in impregnating capacitors.
2. Description of the Prior Art
The compounds having biphenyl skeletons such as isopropylbiphenyl have been widely used as electrical insulating oils, especially those for capacitors.
There are three position isomers of o-isomer, m-isomer, and p-isomer in isopropylbiphenyls. The p-isomer is liable to separate out as crystals, so that it is proposed in U.S. Pat. No. 4,266,264 to increase the content of m-isomer. According to this proposal, the separating out of p-isomer is suppressed and, in this sense, the low temperature characteristic can be surely improved.
The isopropylbiphenyls are widely used as described above, however, the viscosity of them at low temperatures is high and the hydrogen gas absorbing capacity is not always good.
The evaluation of capacitors and the electrical insulating oils for impregnating them is done by testing partial discharge phenomenon. It is considered that the mechanism of the occurrence of this partial discharge correlates to hydrogen gas absorbing capacity. That is, hydrogen gas is generated prior to the occurrence of partial discharge. The hydrogen gas generated in the relevant portion is locally saturated in due course to produce bubbles of hydrogen gas and then the partial discharge occurs. In this procedure, when the quantity of hydrogen gas generation exceeds the capacity of the absorption or diffusion of hydrogen gas, bubbles are produced and finally the partial discharge is caused to occur as described above. Accordingly, in order to increase the quantity of absorption or diffusion, it is required of electrical insulating oils that hydrogen gas absorbing capacity is large and the diffusion of hydrogen gas is good enough.
The hydrogen gas absorbing property itself relates to the molecular structures of insulating oils. The absorption and diffusion of hydrogen gas relates to the viscosity of liquid rather than molecular structures. That is, if an electrical insulating oil is of high viscosity, mass transfer is inhibited and, as a result, the absorption and diffusion of hydrogen gas are suppressed.
The isopropylbiphenyls are characterized in that the viscosity seriously increases a low temperatures. For example, it is said that the isomer mixture of isopropylbiphenyls containing much m-isomer difficultly causes the separating out of crystals, however, its viscosities are 4.6 cSt at 40.degree. C., 1500 cSt at -40.degree. C. and as high as 12,000 cSt at -50.degree. C. The absorption and diffusion of locally generated hydrogen gas are retarded seriously under such high viscosity conditions, therefore, the hydrogen gas is locally saturated to produce bubbles and finally vital dielectric breakdown is brought about.
Therefore, in view of only the viscosity, it cannot always be said that the isopropylbiphenyls are good in low temperature characteristic.
Accordingly, it is eagerly desired to propose an electrical insulating oil which has low viscosity at low temperatures and is excellent in hydrogen gas absorbing capacity. | {
"pile_set_name": "USPTO Backgrounds"
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This invention relates generally to social networking, and in particular to searching topics by highest ranked page in a social networking system.
In recent years, social networking systems have made it easier for users to share their interests and preferences in real-world concepts, such as their favorite movies, musicians, celebrities, soft drinks, hobbies, spoils teams, and activities. Tools have been designed to create nodes on the social networking system that represent web pages that embody these real-world concepts on different domains external to the social networking system. As a result, multiple pages may exist about equivalent real-world concepts.
At the same time, users of social networking systems have shared their interests and engaged with other users of the social networking systems by expressing their interests in these concepts on web pages on different domains external to the social networking system. The amount of information gathered from users is staggering—information describing interests in sports, music, movies, and the like. Social networking systems have recorded this information to personalize the user experience, but social networking systems have lacked tools to enable third-party developers to use this user preference information because of the duplicative pages that have been created on equivalent topics.
Specifically, the information available on social networking systems about users' interests has not been organized to present a singular object for equivalent concepts expressed across different domains. Information about users' interests and preferences is very valuable to third-party developers that seek to drive traffic and increase engagement with their websites. Advertisers may also benefit from this information in marketing interest-based goods and services to users of the social networking system. However, existing systems have not provided efficient mechanisms of organizing and sharing this valuable user preference information. | {
"pile_set_name": "USPTO Backgrounds"
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1. The Field of the Invention
This invention relates to rotating wing aircraft, and, more particularly to rotating wing aircraft relying on autorotation of a rotor to provide lift.
2. The Background Art
Rotating wing aircraft rely on a rotating wing to provide lift. In contrast, fixed wing aircraft rely on air flow over a fixed wing to provide lift. Fixed wing aircraft must therefore achieve a minimum ground velocity on takeoff before the lift on the wing is sufficient to overcome the weight of the plane. Fixed wing aircraft therefore generally require a long runway along which to accelerate to achieve this minimum velocity and takeoff.
In contrast, rotating wing aircraft can take off and land vertically or along short runways inasmuch as powered rotation of the rotating wing provides the needed lift. This makes rotating wing aircraft particularly useful for landing in urban locations or undeveloped areas without a proper runway.
The most common rotating wing aircraft in use today are helicopters. A helicopter typically includes a fuselage, housing an engine and passenger compartment, and a rotor, driven by the engine, to provide lift. Forced rotation of the rotor causes a reactive torque on the fuselage. Accordingly, conventional helicopters require either two counter rotating rotors or a tail rotor in order to counteract this reactive torque.
Another type of rotating wing aircraft is the autogyro. An autogyro aircraft derives lift from an unpowered, freely rotating rotor or plurality of rotary blades. The energy to rotate the rotor results from a windmill-like effect of air passing through the underside of the rotor. The forward movement of the aircraft comes in response to a thrusting engine such as a motor driven propeller mounted fore or aft.
During the developing years of aviation aircraft, autogyro aircraft were proposed to avoid the problem of aircraft stalling in flight and to reduce the need for runways. The relative airspeed of the rotating wing is independent of the forward airspeed of the autogyro, allowing slow ground speed for takeoff and landing, and safety in slow-speed flight. Engines may be tractor-mounted on the front of an autogyro or pusher-mounted on the rear of the autogyro.
Airflow passing the rotary wing, alternately called rotor blades, which are tilted upward toward the front of the autogyro, act somewhat like a windmill to provide the driving force to rotate the wing, i.e. autorotation of the rotor. The Bernoulli effect of the airflow moving over the rotor surface creates lift.
Various autogyro devices in the past have provided some means to begin rotation of the rotor prior to takeoff, thus further minimizing the takeoff distance down a runway. One type of autogyro is the “gyrodyne,” which includes a gyrodyne built by Fairey aviation in 1962 and the XV-1 convertiplane first flight tested in 1954. The gyrodyne includes a thrust source providing thrust in a flight direction and a large rotor for providing autorotating lift at cruising speeds. To provide initial rotation of the rotor, jet engines were secured to the tip of each blade of the rotor and powered during takeoff, landing, and hovering.
Although rotating wing aircraft provide the significant advantage of vertical takeoff and landing (VTOL), they are much more limited in their maximum flight speed than are fixed wing aircraft. The primary reason that prior rotating wing aircraft are unable to achieve high flight speed is a phenomenon known as “retreating blade stall.” As the fuselage of the rotating wing aircraft moves in a flight direction, rotation of the rotor causes each blade thereof to be either “advancing” or “retreating.”
That is, in a fixed-wing aircraft, all wings move forward in fixed relation, with the fuselage. In a rotary-wing aircraft, the fuselage moves forward with respect to the air. However, rotor blades on both sides move with respect to the fuselage. Thus, the velocity of any point on any blade is the velocity of that point, with respect to the fuselage, plus the velocity of the fuselage. A blade is advancing if it is moving in the same direction as the flight direction. A blade is retreating if it is moving opposite the flight direction.
The rotor blades are airfoils that provide lift that depends on the speed of air flow thereover. The advancing blade therefore experiences much greater lift than the retreating blade. One technical solutions to this problem is that the blades of the rotors are allowed to “flap.” That is, the advancing blade is allowed to fly or flap upward in response to the increased air speed thereover such that its blade angle of attack is reduced. This reduces the lift exerted on the blade. The retreating blade experiences less air speed and tends to fly or flap downward such that its blade angle of attack is increased, which increases the lift exerted on the blade.
Flap enables rotating wing aircraft to travel in a direction perpendicular to the axis of rotation of the rotor. However, lift equalization due to flapping is limited by a phenomenon known as “retreating blade stall.” As noted above, flapping of the rotor blades increases the angle of attack of the retreating blade. However, at certain higher speeds, the increase in the blade angle of attack required to equalize lift on the advancing and retreating blades results in loss of lift (stalling) of the retreating blade.
A second limit on the speed of rotating wing aircraft is the drag at the tips of the rotor. The tip of the advancing blade is moving at a speed equal to the speed of the aircraft and relative to the air, plus the speed of the tip of the blade with respect to the aircraft. That is equal to the sum of the flight speed of the rotating wing aircraft plus the product of the length of the blade and the angular velocity of the rotor. In helicopters, the rotor is forced to rotate in order to provide both upward lift and thrust in the direction of flight. Increasing the speed of a helicopter therefore increases the air speed at the rotor or blade tip, both because of the increased flight speed and the increased angular velocity of the rotors required to provide supporting thrust.
The air speed over the tip of the advancing blade can therefore exceed the speed of sound even though the flight speed is actually much less. As the air speed over the tip approaches the speed of sound, the drag on the blade becomes greater than the engine can overcome. In autogyro aircraft, the tips of the advancing blades are also subject to this increased drag, even for flight speeds much lower than the speed of sound. The tip speed for an autogyro is typically smaller than that of a helicopter, for a given airspeed, since the rotor is not driven. Nevertheless, the same drag increase occurs eventually.
A third limit on the speed of rotating wing aircraft is reverse air flow over the retreating blade. As noted above, the retreating blade is traveling opposite the flight direction with respect to the fuselage. At certain high speeds, portions of the retreating blade are moving rearward, with respect to the fuselage, slower than the flight speed of the fuselage. Accordingly, the direction of air flow over these portions of the retreating blade is reversed from that typically designed to generate positive lift. Air flow may instead generate a negative lift, or downward force, on the retreating blade. For example, if the blade angle of attack is upward with respect to wind velocity, but wind is moving over the wing in a reverse direction, the blade may experience negative lift.
The ratio of the maximum air speed of a rotating wing aircraft to the maximum air speed of the tips of the rotor blades is known as the “advance ratio. The maximum advance ratio of rotary wing aircraft available today is less than 0.5, which generally limits the top flight speed of rotary wing aircraft to less than 200 miles per hour (mph). For most helicopters, that maximum achievable advance ratio is between about 0.3 and 0.4.
In view of the foregoing, it would be an advancement in the art to provide a rotating wing aircraft capable of vertical takeoff and landing and flight speeds in excess of 200 mph. | {
"pile_set_name": "USPTO Backgrounds"
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Preschool children and others learning to draw or write may utilize tools, guides or the like to aid in their development. Such tools, guides or the like may help to develop the user's writing instrument control skills, visual motor control skills, fine motor control skills, visual perception skills and bilateral coordination skills. The development of these skills helps to advance and improve the user's writing and drawing skills. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The present invention relates to a machine tool having a working space in which a receptacle for workpieces to be machined, which are exchanged after completion of a machining process, is provided.
2. Related Prior Art
Machine tools of this kind are known from the related art.
The known machine tools generally have cover panels by means of which the working space is closed off from the outside, in order to protect the environment and operating personnel from flying chips and cutting fluid. Provided in the cover panels is an opening, which can be closed off by an operator door, through which the workpieces to be machined are exchanged with already machined workpieces.
The known machine tools generally have a workpiece table on which a receptacle is provided for clamping the workpieces to be machined. When a machining process is complete, the operator door is opened either automatically or by an operator, the receptacle being opened either automatically or by manipulations on the part of the operator so that the workpiece can be removed.
The operator then first cleans the workpiece, still located on the receptacle, using a manually operated spray gun, and then removes it from the working space. Chips are then cleaned off the receptacle by the operator before a new workpiece is then, in a third operation, placed on the receptacle.
The operator must therefore reach into the working space a total of three times in order to exchange a workpiece. These operations are not only physically strenuous, but are also associated with considerable soiling, since the flushed workpiece must be removed by the operator directly from the receptacle and taken out of the working space. This results in soiling not only of the operator but also of the environment outside the machine tool, due to drips of cutting fluid.
In addition to physical exertion and soiling, a further disadvantage with machine tools of this kind is the fact that the aforementioned three operations are necessary in order to exchange a machined workpiece with a workpiece that is yet to be machined. Since these three manipulations are performed by hand, they constitute the speed-limiting step in determining workpiece-to-workpiece time. In the case of piecework in particular, this additionally places the operator under severe performance pressure, so that errors and negligence are unavoidable, especially in cleaning the workpiece and the receptacle.
A further disadvantage thus results because of manual operation in that when receptacles are not completely cleaned, remaining chips, for example, can prevent the newly clamped-in workpiece from sitting correctly in the receptacle, so that deviations in machining accuracy occur.
Some of these disadvantages can be avoided by using automatic workpiece changing mechanisms, although these are associated with a whole series of disadvantages. In addition to the very high cost factor, these workpiece changing mechanisms also constitute a disadvantage in that they require highly qualified personnel, the acceptance of these highly automated machine tools being, in practice, relatively low.
A further disadvantage with automatic workpiece changers lies in the fact that said workpiece changers operate through the usual operator door, so that in the event of maintenance work on the machine tool, there is not only the danger of collisions with the workpiece changing mechanism, but the accessibility of the working space is also considerably degraded by such mechanisms. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention generally relates to a bicycle wheel. More specifically, the present invention relates to a bicycle wheel having a tire retainer for preventing a clincher tire from disengaging from a rim, even if the tire is punctured.
2. Background Information
There are many different types of bicycle wheels, which are currently available on the market. Most bicycle wheels have a hub, a plurality of spokes and an annular rim. The hub is attached to a part of the frame of the bicycle for relative rotation. The inner ends of the spokes are coupled to the hub and extend outwardly from the hub. The annular rim is coupled to the outer ends of the spokes and has an outer portion for supporting a pneumatic tire thereon. Typically, the spokes of the bicycle wheel are thin metal wire spokes.
Generally speaking, there are two main types of bicycle rims. The first main type of a bicycle rim is called a clincher type rim in that the rim has flanges that define annular grooves such that a wire or aramid (Kevlar) fiber bead of a tire interlocks with flanges in the rim. The above types of wheels have been, designed for use with tube tires or tubeless tires. Typically, tubeless tire wheels have an annular seal arranged to seal the spoke attachment openings of the rim. The second main type of a bicycle rim is called a tubular or sew-up rim. In tubular or sew-up rims, a tubular tire with a torus shaped is attached to the rim with adhesive. The tire engagement area of the rim is often provided with a shallow concave cross section in which the tire lies instead of flanges on which tire beads seat. | {
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The invention resides in a solar converter for a photovoltaic solar system and an operating method therefore, in particular a solar inverter with a corresponding operating method for an extended insolation value range.
Converter systems for photovoltaic solar plants for connection to a solar energy generator and to convert the DC voltage of the solar generator to a single or multiphase AC voltage are known in various configurations. In a common configuration they include an intermediate circuit, which is to be connected to the solar generator and one or several capacitors for storing energy, possibly a voltage amplifier arranged between the solar generator and the intermediate circuit to bring the voltage of the solar generator to a required higher level, as well as an inverter which is connected to the intermediate circuit and whose output can be connected to an AC voltage network for supplying energy to one or more consumers for supplying energy thereto. Generally electronic converter arrangements with semi- or full bridge circuits are used which include controllable semiconductor switching elements and which can be controlled by a controller and a control arrangement at high frequency so as to generate an output AC current which, with respect to its phase and amplitude, is adapted to a semi-shaped 50 Hz or 60 Hz network voltage. Configurations of solar inverter systems and corresponding operating methods are, for example, described in DE 102 21 592 A1 DE 100 20 537 A1 and DE 10 2005 024 465 A1.
Solar generators for photovoltaic installations include generally several solar modules arranged in series and, if appropriate, parallel circuits, whose solar cells convert incoming light of the sun directly to electrical energy. The inverter then uses this energy to generate the AC current suitable for the network or the consumer. The inverter needs to operate with high efficiency in order to achieve a high yield. These factors are extremely important in view the relatively high investment expenses for the installation and the operation of a photovoltaic plant. Modern inverter systems may achieve an overall efficiency of up to 98% or even more when operating at rated conditions.
In order to achieve the highest possible yield, the solar generator is operated at the so-called Maximum Power Point (MPP) which is that point of the current-voltage-diagram of the solar generator where the highest energy output can be achieved that is where the product of current and voltage is at a maximum. The MPP operating point is not constant, but depends on the light radiation density, the temperature and the type of the solar cells or, respectively, the solar generators.
MPP operating point is adjusted in a solar inverter often by a so-called MPP-tracker which controls the voltage of the solar generator to the needed value. To this end, the MPP-tracker varies, for example, the current withdrawn by a small amount, calculates the respective product of current and voltage and adjusts the current value toward a higher energy output. As a result, the correct energy output adaptation can be provided even with changing insolation conditions at the solar generator.
However, the converters are usually not designed for the whole light radiation range. Often inverters are used which have a design performance which is about 10% below the maximum energy output of the solar generator. The reasons herefor are that smaller converters are less expensive and have a substantially higher efficiency under partial load conditions. With the light radiation values as prevalent in central Europe, a partial load operation in the area of about 10% to 80% of the rated solar generator output is obtained. Therefore the inverters are designed conventionally only for radiation energy values of up to about 1000 w/m2.
However, weather conditions where the insolation values are higher so that the solar generator produces energy, which the conventionally dimensioned inverter can not accommodate, will also occur. For example, with low ambient temperatures and cloud formations, for short periods, enhanced by reflections on the clouds, high insolation values of up to 1400 w/m2 or more can occur which cause maximum peak energy outputs of the solar generator. A study of G. Wirth, M. Zehner, B. Giesler: “Sizing and Operational Experience with MWp-PV-Systems-Lessons Learned for System Design Tasks”, 2009 estimates the energy of these radiation peaks which are in the range of 1000 to 1400 W/m2 to be up to 8% of the annual energy yield.
Generally with such an excess insolation yield, exceeding the performance limit of the converter, the MPP operating point is moved toward a higher voltage. However, because the under-dimensioned inverter can not accommodate the excess energy yield, it keeps the operating point at values corresponding to its performance maximum whenever the maximum energy yield exceeds the capacity of the inverter. As a result, part of the energy the solar generator could deliver is not utilized and is lost.
In order to avoid this, the above-mentioned study of G. Wirth et. al., recommends not to under-dimension the inverter relative to the solar generator, as it is common practice, but rather to over-dimension it, for example to 110% inverter capacity in relation to 100% solar generator energy output. Such a set-up however has several disadvantages: First, as mentioned earlier, the inverter becomes more expensive with increasing size and capacity. Second, under normal operation with partial load, for example at 10% of the generator rated energy output, the conversion efficiency is detrimentally affected. Finally, a network or consumer which could accept the peak energies is often not available.
Based hereon, it is an object of the present invention to provide a solar inverter system and an operating method which overcomes the disadvantages of the known inverter systems and to better utilize the performance peaks of the light radiation. In particular, it is an object of the present invention to provide a inverter system which is suitable for an extended insolation value range without the disadvantages of an inverter over dimensioning. Advantageously, the overall efficiency of the inverter should be increased with varying insolation conditions. | {
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(1) Field of the Invention
This invention relates to a magnetic tape running direction changeover mechanism which can automatically perform an azimuth alignment, i.e., vertical setting of a magnetic head, no matter in which direction the magnetic tape is caused to run.
(2) Description of the Prior Art
In a tape recorder permitting changeover of the running direction of a tape in either one of the two directions, it is desirable that the magnetic head is brought into contact at an appropriate position with a magnetic tape (hereinafter called "tape" for the brevity or simplicity) no matter in which direction the tape is caused to run.
As a mechanism enabling such an azimuth alignment, one example is disclosed in Japanese Utility Model No. 17624/1983.
The mechanism disclosed in the above-mentioned publication can however effect an azimuth alignment when a tape is caused to run in only one direction. It is difficult to incorporate it in a tape recorder which allows to change the running direction of a tape in either one of two directions. | {
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Enzyme-catalyzed asymmetric reactions have emerged as one of the most important fields in organic and pharmaceutical synthesis. The kinetic resolution of racemic mixtures is still the most common way to get enantiomerically pure compounds on industrial scales and in academic research. Through kinetic resolution, one enantiomer of a racemic mixture is selectively reacted, whereas the other remained unreacted due to differences in transformation rates.
Immobilization of enzymes on solid supports makes them more mechanically robust, thermally stable, and easily separated from the reaction media. The catalyst activity may also be enhanced when enzymes are immobilized due to reduced enzyme aggregation, especially in non-polar organic media. Polymers and inorganic supports are typically used for immobilizing enzymes. Both covalent bonding and non-covalent interaction have been used for enzyme immobilization. The interaction between the enzyme and the support surface has a significant effect on the enzyme loading, catalyst activity, and stability against enzyme leaching during reaction.
Research has been conducted on enzyme immobilization onto mesoporous silica, mostly via physical adsorption. Porous, hydrophobic silica materials are good candidates as supports for immobilized enzymes since their hydrophobicity may facilitate the access of substrates to the entrapped enzymes within their pores. In addition, the weak hydrophobic interaction between enzyme and support allows the former to maintain its active conformation, leading to high activity. However, there still exist some challenges in the immobilization of enzymes onto hydrophobic porous silica. Conventionally, the immobilization involves stirring porous silica support with the enzyme stock. Relatively low enzyme loading is generally achieved due to the low affinity of aqueous enzyme stock solution with the hydrophobic silica support. The leaching of enzymes from the support is another problem associated with the conventional method. Blanco et al (Blanco, R. M.; Terreros, P.; Fernandez-Perez, M.; Otero, C.; Diaz-Gonzalez, G. J. Mol. Catal. B: Enzym. 2004, 30, 83) has reported that leaching of lipase from a hydrophobic mesoporous silica is not likely in anhydrous media, and the immobilized lipase remains active for 15 reaction cycles in acylation of ethanolamine with lauric acid. However, the period of each cycle is only one hour. If stirred for a longer time in anhydrous organic solvent, leaching of enzymes would be likely to occur.
There is therefore a need for a method for immobilizing an enzyme on and/or in a solid support such that leaching of the enzyme from the support is reduced. The method would preferably provide high reactivity of the enzyme and improved thermal stability of the enzyme relative to unimmobilised enzyme. | {
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The present invention relates generally to systems that promote healthy lifestyles and, more particularly, to weight loss systems. The present invention is an improvement upon existing weight loss systems in that it tracks, monitors, and analyzes data to improve compliance with a personalized health plan. The present invention may be used to motivate dieters as well as keep them on a healthy diet while at the same time allowing flexibility in different dieting aspects including, but not limited to, types of food, amount of food, types of food preparation, and amount of exercise.
Dieting has become an extremely popular activity resulting from people's awareness of the health risks of becoming overweight or obese, a desire to improve one's appearance, and an aspiration to achieve the sense of accomplishment that comes from setting a difficult goal and accomplishing it. However, there is no singular method of dieting that works for every person. Body types, weight loss goals, and preferences vary greatly depending on the individual. Every dieter has individual likes and dislikes as to types of food, times and places to eat, type and length of exercise, eating habits, etc. Due to these differences, many dieters become frustrated with rigid, impersonal diets, and often quit the diet after a short time.
Furthermore, dieters differ on how well they can motivate themselves to continue to adhere to certain dietary guidelines. For example, a dieter who is supposed to only eat a cup of pasta and a vegetable for lunch, but instead decides to eat an ice cream cone as well may be unable to justify such a decision within the diet and decide to give up the diet for the rest of the day. Because such “splurges” are detrimental to the dieter's physical and mental progress, the dieter may find the diet unsustainable.
Many diet plans fail to allow for individualized exercise schedules. Typically, the diet plans suggest the same workout schedule for every person on the diet. For example, the diet plan may incorporate a workout of a half hour, two to three times a week. Such a generalized workout schedule has a number of weaknesses. First, it fails to factor in the type of activity the person is performing. The effectiveness of the exercise depends on what exercise is performed as well as the intensity. A half hour of strolling through a park is simply not as effective as a half hour of running.
Second, it does not allow for individualized ability. For some people, working out for half an hour, two to three times a week, may be physically impossible given their current condition. It may be possible for them in the future, but the person may to a 15 minute workout for until his or her health improves. Other individuals may have the desire and ability to work out for a longer period of time or a greater number of times per week.
Another problem with a general workout schedule is that it fails to factor in the individual's likes and dislikes as to type of activity and time of day to perform the activity. A plan that proposes exercise two to three times a week is easily put aside when the person is busy and distracted by other activities. A person is much more likely to perform an activity that is scheduled or better yet, for which a reminder is provided telling the person to perform a certain activity at a certain time.
Finally, existing diet plans often fail to take into account details regarding the user's dietary information. The two parts of the diet plan—the intake of food and exercise—are generally treated as separate parts of the plan. However, the two are related in that they both have an impact on caloric intake. The more one exercises, the more one can eat. Accounting for both activities allows the impact of one to be applied to the other. For example, a person may eat a large lunch one day and reduce the impact of the lunch by including an extra work out later in the week. Likewise, a person could miss a scheduled workout and compensate for it by eating a smaller meal later in the day.
A highly effective solution to many diet program problems is found through the use of coaching. Research has shown that dieting and weight loss is more successful when the dieter is coached throughout the process. Coaching keeps the dieter motivated, provides positive reinforcement, and introduces a narrowly-tailored plan for each individual participant. However, obtaining a reliable human coach is difficult and prohibitively expensive such that relatively few dieters are actually able to use one. | {
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The present disclosure relates generally to resonant converters. Resonant converters, including zero-voltage transition (ZVT) pulse width modulation (PWM) converters and zero-current transition converters (ZCT) PWM converters offer a number of benefits including, for example, allowing high switching frequencies, reducing electromagnetic noise emission, and allowing use of smaller passive components. Existing resonant converters, including the foregoing examples, suffer from a number of shortcomings and disadvantages. There remain unmet needs including inductor saturation, post commutation oscillation, voltage imbalance. For instance, some ZVT PWM converters include coupled inductors which are prone to saturation during converter operation and cause post commutation oscillation. In another example, some ZVT PWM converters use neutral point connections which cannot balance voltage easily and do not work for DC/DC power conversion. There is a significant need for the unique apparatuses, methods, systems and techniques disclosed herein. | {
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1. Field of the Invention
The present invention relates to a wireless distance measurement system and a wireless distance measurement method that measure the distance between a wireless communication terminal apparatus and a base station apparatus using UWE (Ultra Wide Band) communication scheme.
2. Description of the Related Art
One of high-speed wireless transmitting techniques includes the UWB communication scheme. The UWB communication scheme is a technique of performing ultrahigh speed wireless communication using a pulse signal sequence formed with a pulse signal synchronized with a timing of a predetermined period. An example of UWB communications is known that communication is carried out using a pulse signal sequence formed with extremely short pulse signals having a pulse width of 1 nanosecond or less without using carrier waves.
Meanwhile, for example, Patent Document 1 discloses a distance measurement technique, in which a base station apparatus (hereinafter “base station”) measures the distance to a wireless communication terminal apparatus (hereinafter “terminal”). The distance measurement technique disclosed in Patent Document 1 uses differences between times of arrival of signals received at a terminal using 3 or 4 base stations.
FIG. 1 shows the positioning system disclosed in Patent Document 1. Referring to FIG. 1, the positioning system has a plurality of base stations 11, 12 and 13, and calculation server 14, and, base station 11 to 13 and calculation server 14 are connected by wired network 15. This positioning system is directed to calculating the position coordinate of terminal 10.
In the system disclosed in Patent Document 1, positioning of a terminal is conducted using propagation time differences between measurement signals transmitted and received between the terminal and the base station. To find the absolute time of signal propagation, it is necessary to synchronize the clock of a terminal and the clock of the base station. However, in a general wireless communication system, a terminal and the base station are not synchronized, and therefore it is not possible to conduct positioning (i.e. TOA: Time Of Arrival) using absolute propagation time. However, when a plurality of base station clocks are synchronized, it is possible to find differences of times a measurement signal takes to arrive at the base stations, and it is possible to conduct positioning (i.e. TDOA: Time Difference Of Arrival) using relative propagation time (propagation time difference) Patent Document 1: Japanese Patent Application Laid-Open No. 2004-242122
However, with the positioning system disclosed in above Patent Document 1, the differences between propagation times a measurement signal takes to arrive at a plurality of base stations are used for measurement, and therefore, it is necessary to synchronize the clocks of a plurality of base stations. Consequently, it is necessary to connect the base stations with a cable, or provide a reference station to make clocks to be synchronized besides the base stations for measurement. Further, to measure the distance to a terminal from differences of propagation times for a plurality of base stations, it is necessary to keep the relative position relationships between a plurality of base stations as data, and there is a problem that the positions of the base stations should be measured in advance. | {
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The demand for smaller device feature sizes has necessitated the move to smaller exposure wave lengths in photolithography. However, light reflection from a given substrate increases with decreasing wavelength of said light. This degrades the performance of photolithographic tools due to reflective notching and thin film interference effects. Anti-reflection layers (ARLs) have been widely used to overcome these problems through destructive phase cancellation or full absorption so as to minimize formation of standing waves in the resist layers. ARL 12 is placed between photoresist layer 13 and substrate 11, as shown in FIG. 1.
Organic ARLs, applied through spin-on techniques, were initially the materials of choice but, as device geometries have continued to shrink into the deep sub micron regime, inorganic materials such as silicon oxynitride, deposited by means of PECVD (plasma enhanced chemical vapor deposition), have proven to be more suitable for the shorter light wavelengths that must, of necessity, be used. The PECVD ARL does, however, have certain problems of its own. In particular, distortion of line profiles in developed photoresist images may occur.
In FIG. 2 we show an idealized cross-section of a line 23 that was formed through proper processing of photoresist layer 13 (of FIG. 1). FIGS. 3 and 4 show common distortions of this line profile that can occur when layer 12 is a ARL of the PECVD type. In FIG. 3, a T-top of additional material 34 has grown out from the line near its top surface while in FIG. 4 additional material 44 is seen to have grown out at the substrate level to provide the line with an added, and unwanted, footing.
It is now known that the origin of these line profile distortions is the presence on the surface of the PECVD ARL of amino (NH.sub.2) groups that settle there during the PECVD process. While the ARL is being made ready to receive a layer of photoresist there is often a delay. Additionally, it gets exposed to the air and acidic airborne contaminants and/or basic contaminants at the substrate surface react with the amino groups to form the outgrowths 34 and 44 shown in FIGS. 3 and 4 respectively, leading to a spurious increase in line width within the photoresist pattern.
Various attempts to deal with this problem of photoresist profile instability have been described in the prior art. Among the techniques tried in the past, one of the more popular approaches has been to add an oxide cap over the surface of the ARL immediately following its deposition and prior to exposure to air and later application of the photoresist. Another approach has been to expose the PECVD ARL to a nitrous oxide plasma immediately after its formation. While partially successful, none of these prior art techniques has been able to reliably and completely remove the contaminating amino groups from the surface of an anti-reflective layer.
A routine search of the prior art did not uncover any teachings similar to the present invention. Several references of interest were found, however. For example, Lee (U.S. Pat. No. 5,834,372) teaches a method for pre-treating a semiconductor surface. He purges with an inert gas and then introduces tungsten fluoride gas which is exposed to the surface and improves its nucleation capability for subsequently deposited films.
Yeh et al. (U.S. Pat. No. 5,783,493) subject a BPSG (borophosphosilicate glass) layer to a plasma of argon, nitrous oxide, nitrogen, or oxygen, at a relatively low power (low density plasma), after etch back. This treatment suppresses subsequent precipitation of defects in the BPSG surface.
Yau (U.S. Pat. No. 5,716,890) uses a capping layer of silicon oxide as part of an ILD fabrication process. Said capping layer may, optionally, be exposed to a nitrogen or argon plasma which etches part of the cap away.
Huang (U.S. Pat. No. 5,679,211) uses an oxygen containing plasma as a means to clean the surface of a SOG (spin on glass) in order to remove a polymer residue formed there during a prior etch back processing step. | {
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Ellipsometer or Polarimeter and the like systems, allow determination of Sample System physical and optical properties, (such as thickness, refractive index and extinction coefficient of surface films thereon, by detecting change in the "Polarization State" of a beam of polarized light which is caused to interact with said Sample System, where Polarization State here refers to a set of values for Polarized Light Beam Quadrature Components, (such as "S" and "P"), Magnitude Ratio, and a Phase Angle therebetween. (It is noted that "P" refers to that component which is in a plane containing the normal to a Sample System and incident and/or transmitted beam(s) of polarized light, and "S" refers to that component perpendicular thereto and parallel to the surface of said Sample System. It is also noted that a "full" polarization state also requires designation of an absolute value to which a magnitude ratio is referenced, and the direction of rotation of a polarized beam of light).
Ellipsometer Systems generally can be broadly classified as Rotatable or Intensity Modulating Rotating Element Ellipsometers (REE) and Phase Modulating Modulation Element Ellipsometers (MEE). For instance, a Patent to Woollam et al., U.S. Pat. No. 5,373,359, describes a Rotating Analyzer Ellipsometer (RAE) in which a Light Source provided beam of light is caused to pass through a Polarizer, (which serves to set a Polarization State therein), then interact with a Sample System. Said interaction with said Sample System serves to alter the Polarization State of said polarized beam of light, which polarized beam of light then sequentially encounters a Rotating Analyzer and a Dispersion Optics, (e.g. a Diffraction Grating is specified), which forms therefrom a multiplicity of essentially single wavelength polarized beams of light. Said multiplicity of essentially single wavelength polarized beams of light are then caused to enter a Photo Detector Array, in which Photo Detector Array, individual Detector Elements serve to develop a representative signal for each. Fourier Analysis, for instance, of said signals allows determination of parameters which allow determination of Sample System characterizing PSI and DELTA values. It is noted that in said Woollam et al. (RAE) there is no additional focusing applied after the polarized beam of light encounters the Sample System. Another Patent, to Ducharme et al. U.S. Pat. No. 5,416,588, on the other hand, describes a Modulation Element Ellipsometer (MEE) comprised of a Light Source, a Polarizer, a Polarization State Modulator Element, a means for splitting Quadrature Components in a Beam of Polarized Light after interaction with a Sample System, two Detector Elements and an Analysis System. In use a beam of light is provided by the Light Source and a state of Polarization is set therein by said Polarizer, after which the polarized beam of light is subjected to a Polarization State Modulation and caused to interact with a Sample System, which Sample System changes the State of Polarization of said Phase Modulated Polarized beam of light. Quadrature Components of said Polarized beam of Light are then isolated and subjected to separate, for instance, Fourier Analysis. Appropriate utilization of the Coefficients of the terms of a Fourier Series allows determination of Sample System characterizing PSI and DELTA values. It is noted the described Modulation Element Ellipsometer (MEE) utilizes Coefficients from Fourier Series based upon both Quadrature Components. Some Modulation Ellipsometers utilize Fourier Series Coefficients based upon only one such Quadrature Component. While the specifics of signal generation are different in (REE) and (MEE) ellipsometers, and even amongst Ellipsometers of similar type, the end result of utilization thereof is provision of PSI and DELTA values for Sample Systems analyzed therein. This is the case regardless of Sample System type (e.g. isotropic, anisotropic or anisotropic and depolarizing).
In the above the terms Polarizer and Analyzer were utilized, and it is to be understood that said elements can be essentially similar and are identified primarily by location in an Ellipsometer or Polarizer and the like system. Polarizers are positioned ahead of a Sample System, and Analyzers thereafter. As well, Compensators can be present, for instance, between Polarizers and Analyzers, and after Analyzers. Compensators generally operate to change a phase angle between quadrature components of a polarized beam of light, via a birefringence property which serves to retard one quadrature component differently than the other. Polarizers, Analyzers and Compensators can be Rotatable, Rotating and Stationary in use.
Numerous other Ellipsometer Systems could be described, which are, for instance, comprised of various combinations of:
Stationary Polarizer(s); PA1 Stationary Compensator(s); PA1 Stationary Analyzer(s); PA1 Rotatable Polarizer(s); PA1 Rotatable Compensator(s); PA1 Rotatable Analyzer(s); PA1 Rotating Polarizer(s); PA1 Rotating Compensator(s); PA1 Rotating Analyzer(s); PA1 Modulator Element(s). PA1 a. Rotatable Element Nulling Ellipsometers (RENE); PA1 b. Rotatable Element Automated Nulling Ellipsometers (REANE); PA1 c. Modulation Element Ellipsometers (MEE); PA1 d. Rotating Analyzer Ellipsometers (RAE); PA1 e. Rotating Polarizer Ellipsometers (RPE); PA1 f. Rotating Compensator Ellipsometers (RCE); PA1 g. Rotating Polarizer and Analyzer Ellipsometers (RPAE); PA1 h. Rotating Polarizer and Analyzer, Fixed Compensator (RPAFCE); PA1 i. Rotating Analyzer and Compensator, Fixed Polarizer Ellipsometer (RACFPE); PA1 j. Rotating Polarizer and Compensator, Fixed Analyzer (RPCFAE); PA1 k. Rotating Analyzer, Fixed Polarizer and Compensator Ellipsometer (RAFPCE); PA1 l. Rotating Polarizer, Fixed Analyzer and Compensator Ellipsometer (RPFACE); PA1 m. Rotating Compensator, Fixed Analyzer and Polarizer Ellipsometer (RCFAPE); PA1 (Note that similar identifying descriptions also apply to Polarimeter and the like Systems).
Examples of Ellipsometers to which the present invention system and method of application can be applied are, for instance:
However, for the purposes of the present invention it is not necessary to describe each above listed system in detail. The present invention, while applicable to essentially any Ellipsometer or Polarizer and the like System, is focused upon the simultaneous production of a plurality of measureable Orders of essentially single wavelength polarized beams of light from a polychromatic beam of light, which polychromatic beam of light has been caused to interact with a Sample System. (Note that a Dispersive Optics actually provides a continuous spectrum of spacially separated wavelengths which are present in a Polarized Source Light Beam. It is convenient, however, to view said spectrum as a multiplicity of essentially single wavelength polarized beams of light. Such an approach has particular relevance where, because of size and placement, a Detector Element intercepts a relatively narrow band of said wavelengths centered about some wavelength in a physically realized system).
Continuing, the Woollam et al. U.S. Pat. No. 359 Patent identified above, presents a system of two Diffraction Gratings toward the end goal of the present invention, wherein a polarized beam of light Diffracted by one Diffraction Grating is caused to impinge upon another and provide a second spectrum of wavelengths. There exists, however, need for an improved approach to simultaneously providing a plurality of "Orders" per se. of polarized essentially single wavelength polarized beams of light. The reason for this is that simultaneous analysis of information in a plurality of essentially single wavelength polarized beams of light, which essentially single wavelength polarized beams of light are derived from a polychromatic polarized beam of light, which polarized polychromatic polarized beam of light has been caused to interact with a Sample System, allows more convenient characterization of more complex Sample Systems.
A paper titled "Division-Of-Amplitude Photopolarimeter Based on Conical Diffraction For a Metallic Grating" by Azzam, in Applied Optics, Vol 31, No. 19, 1 Jul. 1992 and U.S. Pat. No. 5,337,146 are also noted. The purpose of the System and Method of Use described in said references is to allow simultaneous measurement of all four Stokes Parameters of a Beam of Light. The System involved is a Gratting which serves to provide Four Orders, each of which must be intercepted, possibly by a Detector Array. While the present invention System is to some extent similar to that alluded to in said Azzam references, it is to be appreciated that the Purpose to which the present invention System speaks, and the Method of Use thereof are very different than that described by Azzam. As well, the Azzam System, while providing for Polarization of wavelengths in certain Orders, does not provide for the filtering-out of stray light or of overlapping portions of adjacent Orders to provide wavelengths of an Order free of any masking influence of wavelengths present in an adjacent Order. The present invention provides that multiple, element filters be present, which, in the context of spectroscopic ellipsometer or polarimeters and the like has not, to the inventor's knowledge, been previously known.
The present invention then, as taught supra in this Disclosure, is a multiple "Order" producing Dispersive Optics system and method of application thereof, for use in providing a multiplicity of essentially single wavelength polarized beams of light, in combination with Ellipsometers and/or Polarimeters and the like. The purpose thereof is to allow simultaneous detection and analysis of closely situated wavelengths, by interception thereof in different Multiple Order producing Dispersive Optics produced Orders, which closely situated wavelengths can not be simultaneously detected in a single Order because of Detector Element finite dimension limitations. | {
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An important class of photographic films are black-and-white silver halide films intended to be used for contact exposures in the field of graphic arts. Such films require a high degree of dimensional stability as well as a surface which is non-tacky, and has a suitable degree of roughness to facilitate rapid vacuum draw-down during contact exposure. Advantageously, these films are relatively low in photographic speed so that they can be used under bright safelight or even ordinary room-light conditions. To facilitate handling in use, it is highly desirable that the front and back surfaces of the contact film be readily distinguishable by the user.
An additional highly desirable property for the aforesaid graphic arts contact films is the ability to optically spread the image during contact exposure. Thus, for example, in employing dot image originals, it is desirable to be able to regulate the degree of dot growth that occurs on contact exposure. Also, the original which is to be exposed in the contact exposure process can, in some instances, be a multi-layer original, that is, an original in which two or more elements have been stacked together as an assembly. Such a multi-layer assembly can include both line image originals and dot image originals. The ability to optically spread the image during exposure is critically important in handling such stacked originals in a single exposure process. In particular, optical spreading can improve the image quality of characters produced from originals which are out of contact with the contact film.
Optical image spread is distinguished from chemical image spread which involves infectious imagewise development of unexposed photographic silver halide grains in close proximity to exposed photographic silver halide grains. Chemical image spread is achieved by incorporation of a nucleating agent in either the film or the developing solution. A given system can employ either optical image spread or chemical image spread or both.
To facilitate optical spreading of an image during contact exposure, it is important that the silver halide emulsion layer of the contact film be widely spaced from the surface of the contact film that comes into face-to-face contact with the original, such surface typically being the surface of a protective overcoat layer which serves as the outermost layer of the film.
It is increasingly common in the graphic arts to employ a computer assisted "dry dot etching" process in making color corrections to halftone separations. The process can be carried out without the use of masks for color correction of an entire separation, or it can be done with hand-cut masks or photographic masks for local color corrections. Techniques used in dry dot etching vary from shop to shop, but all depend on the ability of a contact or duplicating film to change dot size with overexposure (overexposure meaning an exposure greater than that necessary to produce dot-for-dot reproduction in the midtone dot values). Generally, the dot-change exposure technique starts with a dot-for-dot exposure and adds a "bump", or additional, exposure to produce the desired change in dot value. This "bump" exposure may be confined to a localized area of the subject by masking, or it may be combined with the dot-for-dot exposure to make an overall change to the separation. Contact films which are best suited for use in dry dot etching are those that provide a high degree of optical spread.
It is exceedingly difficult to incorporate in a photographic film all of the properties that are desirable for use as a contact exposure film in the graphic arts. Thus, for example, the use of a very thick overcoat layer to provide the desired spacing between the surface of the film and the silver halide emulsion layer is impractical, since it adversely affects dimensional stability. To improve dimensional stability, a polymer latex can be incorporated in the overcoat layer, but this tends to render the surface undesirably tacky. Also, if the overall thickness of the hydrophilic layers, including the emulsion layer and overcoat layer, becomes too great, the diffusion of developing agents and fixing agents to the emulsion layer will be impeded and the time required for development and fixing will be excessive. Yet another problem will be the prolonged drying period needed to dry the processed film.
The present invention is directed to a novel contact film for use in the graphic arts which effectively overcomes all of the above problems and combines a wide variety of desired features in a single film. | {
"pile_set_name": "USPTO Backgrounds"
} |
The offset collision denotes that in a case where two railcars 31 and 32 are running in directions opposite to each other, one vehicle (hereinafter may be referred to as an “oncoming vehicle”) 31 derails from a track and collides with a part of the other vehicle (hereinafter may be referred to as a “running vehicle”) 32 as shown in FIG. 9. Various countermeasures against the offset collision are being taken in railcars. As one example of the countermeasure against the offset collision, it is effective to configure a side bodyshell by using a double skin structure as in PTLs 1 and 2 to improve the stiffness of the side bodyshell or form an inclined surface at a front end portion of the side bodyshell of each of the vehicles 31 and 32 such that the vehicles 31 and 32 separate from each other at the time of the collision. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention relates to a system carrier for freely programmable blocks (gate arrays) that are connected to one another by means of buses.
In the development of complex integrated circuits (IC) first of all logic designs are created, which are based on a speech-based description in a programming language, the hardware description language (HDL) as it is known. For the purpose of functional verification of highly integrated microelectronic circuits, it is usual to use logic simulation in the development phase. As a supplement to the simulation, in recent years specific platforms for the logic emulation have been used. The circuit, which is present as a network list and is to be verified, was partitioned onto freely programmable logic blocks (FPGA) which are connected by means of specific programmable switching matrices. This technique is known as rapid prototyping. The developer is therefore made capable of testing the circuit on the platform in an early development phase of a logic design before said circuit is cast in silicon.
The drawback with this system is that, because of the switching matrix, considerable propagation time delays have to be tolerated, which makes the verification of the logic design more difficult or even impossible. Added to this is the fact that the programmable blocks are placed fixedly on the platform and are connected to one another via the switching matrix by likewise fixed connections. | {
"pile_set_name": "USPTO Backgrounds"
} |
With popularization and development of household microwave ovens, more and more people begin to use the microwave oven to thaw frozen food because of advantages (such as fast speed and high efficiency) of the microwave oven.
At present, people usually do not eat bought food (such as meat, fish, etc.) all at once in daily life, and some of the food may be frozen for eating next time. Therefore it is necessary to study microwave thawing of food.
In order to study current situation of microwave thawing, 6 microwave ovens with different brands and different models are chosen from the market to thaw 500 grams of minced beef, and following results are obtained.
periodmaximumminimumcookedoffire-temper-temper-discol-BrandsModelsthawingpoweratureatureorationBrand 1Model 1 2′12″Automatic67.0° C.−2.2° C.YesBrand 2Model 215′00″Automatic29.6° C.−1.8° C.NoBrand 3Model 321′17″Automatic42.1° C.−0.5° C.YesBrand 4Model 4 7′00″Automatic48.2° C.−1.9° C.YesBrand 5Model 513′00″Automatic67.6° C.−1.3° C.YesBrand 6Model 611′00″Automatic41.9° C.−2.0° C.Yes
It can be seen from the above table that, microwave ovens of most brands have following problems. {circle around (1)} A period of thawing is long, in which the longest period is 27′17″. {circle around (2)} There is the cooked discoloration. {circle around (3)} A temperature difference is too large, in which the largest temperature difference reaches 69.2° C. The reason for occurring these problems is that an optimal temperature at thawing endpoint is not defined, thus lacking research on thawing procedures (such as firepower and period), and resulting in non-ideal effect of thawing. Therefore, it is urgent to research and improve the optimal temperature at thawing endpoint and a control method for thawing food by a microwave oven. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a program control circuit for use in a program controlled apparatus such as a microcomputer.
2. Description of Related Art
The advancement of integrated circuit technology has made it possible to assemble a considerably complicated logic circuit in a single chip of an integrated circuit. Such an integrated circuit can be exemplified by a single chip microcomputer, which has in turn become very complicated and diversified because of the complication of logic circuits which can be realized in an integrated circuit chip.
On the other hand, microcomputers are adapted to execute programs read from an internal memory or an external memory. In such a program controlled computer, how short and how clean a program is described is very significant to the high speed processing of data.
One typical example of an operation which requires a short and clean program is a numerical data processing, which requires a solution having a high degree of precision. For the purpose of elevating the precision of a solution, it is an ordinary practice to repeatedly execute the same processing. In this case, if the same program to be repeatedly executed is continuously described at the times corresponding to the number of repetitions, a short and simple program cannot be obtained. At present, therefore, there has been actually widely used such a method as to combine a processing program to be repeated and a conditional jump instruction so as to shorten a program to be prepared.
For example, the number of repetitions "N" of an operation program to be repeatedly executed is set in a register, and the operation program is repeatedly executed while decrementing the value held in the register by "1" after each one execution of the operation program. Then, when the value held in the register becomes "0", the repeated execution of the operation program is completed, and the next processing will be executed.
In the above mentioned repeated program execution, however, each time the operation program to be repeatedly executed is executed, not only the value held in the register must be decremented, but also, a discrimination must be made as to whether or not the value of the decremented register fulfills a given condition. This is done so that a determination is made on the basis of the discrimination as to whether the operation should be returned to the operation program to be repeatedly executed or whether it should go to the next program away from the operation program to be repeatedly executed. For discrimination on the content of the register, a logic circuit for discrimination should additionally be provided. Further, an instruction for executing the discrimination is required, and if the instruction is described in a program as one independent instruction, such a discrimination instruction must be executed the same number of times as the repetition number required for a repeated operation. Therefore, the larger the repetition number of the operation becomes, it follows that the time of the executions of the discrimination instruction increases, so that a total operation time of a program will inevitably become lengthy. In addition, if a repeated operation program contains therein another repeated operation subprogram, the time of the executions of discrimination instructions increases further, so that the number of program steps and a necessary processing time will become very large. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to electro-optic waveguide devices, in particular to electro-optic modulators, to a method of fabricating travelling-wave RF electro-optic modulators and devices produced thereby.
2. Discussion of Prior Art
Conventional wafer based waveguides provide a convenient means for guiding light within a semiconductor wafer. In such waveguides light is confined within a core layer by cladding layers, exhibiting a lower refractive index than the core material, arranged above and below the core layer. Light is confined at the edges of the waveguide by the core/air interface.
For example, such waveguides can be fabricated from III–V semiconductors such as lattice matched GaAs/AlGaAs. In this example the refractive index of the general material AlxGa(1-x)As depends on the aluminium mole fraction (x). Propagation of light may be confined primarily to the plane of the semiconductor wafer by growing epitaxial layers of AlxGa(1-x)As with different values of the aluminium mole fraction x. Propagation of light may be further confined to a narrow waveguide by etching the requisite waveguide pattern into the AlxGa(1-x)As layers.
It is well known that the optical properties of the waveguide may be altered by applying an electric field across the waveguide. For example the refractive index of the waveguide core (and the upper cladding layer) may be altered via the linear electro-optic effect (Pockels effect), which in turn may be used to alter the phase of light passing through the waveguide.
In practice, the core and upper cladding layers are undoped and behave effectively as insulators. The lower cladding layers are usually doped to provide a conducting layer below the waveguide. The substrate is usually undoped and also behaves effectively as an insulator. By placing an electrode on the top of the waveguide, and a second electrode in contact with the doped lower cladding layer, an electric field can be applied across the guiding region by applying a voltage between the upper and lower electrodes. Accordingly, the refractive index of the waveguide core, and hence the phase of light passing through the waveguide, may be modulated electrically.
This effect provides the basis for electro-optic waveguide interferometers in which light can be switched from one output to another by applying an electric field across the waveguide.
The linear electro-optic effect is a very fast effect, and the switching speed of the waveguide interferometer depends mainly on how quickly the voltage can be applied to the electrodes. For a simple electro-optic waveguide interferometer the switching speed will be limited by the capacitance of the electrode, or in practice, by the capacitance of the bond pad used to connect a wire to the electrode.
The linear electro-optic effect is however a weak effect, necessitating long electrodes (of the order of tens of millimeters in length) within the device in order to keep the drive voltage at acceptable levels. The length of the electrode can cause complications if the device is to be operated at very high switching speeds (for example where the interferometer is switched at radio frequencies (RF) of the order of 50 GHz) since the length of the electrode is long compared to the wavelength of the RF drive signal (for example, a 50 GHz drive signal has a wavelength of 6 mm in air). This means the transit time of the light under the electrode would correspond to a few RF cycle periods. The light would be phase shifted in one direction by the positive half-cycles of the RF drive signal, and then phase shifted in the opposite direction by the negative half-cycles, before it has had time to pass under the full length of the electrode. The total phase shift would be small, if not zero, and so the device would not be very efficient.
To overcome this effect, the RF wave must be made to travel along the device in the same direction, and at the same speed, as the light in the waveguides. In this manner the same part of the RF wave always acts on the same part of the light beam, and the required optical phase shift grows continuously as the light propagates along the device. This type of device is called a “travelling-wave” electro-optic waveguide modulator.
One of the main difficulties in making this type of travelling-wave electro-optic modulator is that the epitaxy needed to apply the RF drive signal to the waveguide has to have conducting lower cladding layers in order to confine the applied field strongly in the core and upper cladding layers only.
Due to the high frequency of the drive signal, coplanar stripline is employed to route the RF drive signal to the modulator electrodes. If the coplanar stripline (CPS) were placed on top of the conducting layers of epitaxy (the doped lower cladding layer of the waveguide), the CPS line would be very lossy and the RF drive signal would propagate only a few millimeters at most before being completely attenuated by the conducting layers. Ideally, the CPS line should be placed on an insulating (or in semiconductor terms, semi-insulating) substrate to avoid severe losses. However, further processing would then be required to provide a conducting epitaxial layer beneath the waveguide in order to confine the applied field within the waveguide core and upper cladding layers.
An alternative method of reducing unwanted attenuation of the RF drive signal is to fabricate the device on a semi-insulating substrate and to etch a deep trench between the coplanar stripline primary electrodes and any conducting epitaxy employed underneath the waveguide core, thereby effectively isolating the two structures. In this configuration bridging electrodes are utilised to span the trench between the coplanar stripline and the waveguide [see for example “High-speed III–V semiconductor intensity modulators”, Walker R G, IEEE Journal of Quantum Electronics, 27: (3) 654–667 March 1991]. However, this isolation technique is complex and expensive due to low processing yields. The technique also results in a non-planar substrate making subsequent processing of the device more difficult.
It is an object of the present invention to provide an improved method for producing an electro-optic waveguide modulator and specifically for producing a travelling-wave electro-optic modulator. | {
"pile_set_name": "USPTO Backgrounds"
} |
Measurement catalogs collate and provide detailed documentation of potential performance metrics. However, at present measurement catalogs only exist in a paper-based format that does not permit convenient updating.
With such paper-based metric catalogs, the process of identifying suitable metrics for monitoring a process is tedious, cumbersome and time-consuming. In particular, it is necessary to use complex and user-unfriendly paper sheets (which do not provide any guidance or support to the user regarding the selection of appropriate metrics). Indeed, the CMMI specification book is the only source of guidance to the user.
Furthermore, since CMMI process areas are not clearly understood, the relationship between the CMMI process areas and the business requirements of a user organization typically had to be manually adjusted. Finally, such previous methods of identifying appropriate metrics are not easily re-used in other circumstances. Consequently, a huge amount of time and effort must be expended using the above-mentioned prior art methods, to enable metrics to be selected for each new client.
When measurement catalogs have been implemented in electronic form (e.g. the IBM Application Services Management (AMS) Measurement Catalog) in the past, the definition of metrics provided therein have been typically insufficient. Furthermore, the relationships between the various components of computed metrics have not been clearly described. | {
"pile_set_name": "USPTO Backgrounds"
} |
Currently, liquid crystal display devices have been widely used in our lives. In order to achieve a high resolution and a narrow bezel, usually a Gate Driver on Array (GOA) technique is adopted in the liquid crystal display devices. As an important member for the GOA technique, a gate driving circuit may include a plurality of gate driving units (also called as shift register units) connected in a cascaded manner, and each gate driving unit may be connected to one gate line so as to apply a signal thereto, thereby to scan pixels progressively.
For most of the gate driving units in related art, one trigger signal is merely used to trigger one shift register signal. In other words, in the related art, the gate driving unit merely outputs one gate driving signal, so as to drive the pixels in one row. In this regard, the entire gate driving circuit includes a large number of gate driving units, and a large area is occupied thereby, so it is adverse to the miniaturization and the low cost of a display panel. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention is directed towards a belt use in papermaking, more particularly, a grooved belt having rebates for use in the press section of a papermaking machine.
2. Description of the Prior Art
During the papermaking process, a cellulosic fibrous web is formed by depositing a fibrous slurry, that is, an aqueous dispersion of cellulose fibers, onto a moving forming fabric in the forming section of a paper machine. A large amount of water is drained from the slurry through the forming fabric, leaving the cellulosic fibrous web on the surface of the forming fabric.
The newly formed cellulosic fibrous web proceeds from the forming section to a press section, which includes a series of press nips. The cellulosic fibrous web passes through the press nips supported by a press fabric, or, as is often the case, between two such press fabrics. In the press nips, the cellulosic fibrous web is subjected to compressive forces which squeeze water therefrom, and which adhere the cellulosic fibers in the web to one another to turn the cellulosic fibrous web into a paper sheet. The water is accepted by the press fabric or fabrics and, ideally, does not return to the paper sheet.
The paper sheet finally proceeds to a dryer section, which includes at least one series of rotatable dryer drums or cylinders, which are internally heated by steam. The newly formed paper sheet is directed in a serpentine path sequentially around each in the series of drums by a dryer fabric, which holds the paper sheet closely against the surfaces of the drums. The heated drums reduce the water content of the paper sheet to a desirable level through evaporation.
It should be appreciated that the forming, press and dryer fabrics all take the form of endless loops on the paper machine and function in the manner of conveyors. It should further be appreciated that paper manufacture is a continuous process which proceeds at considerable speeds. That is to say, the fibrous slurry is continuously deposited onto the forming fabric in the forming section, while a newly manufactured paper sheet is continuously wound onto rolls after it exits from the dryer section.
Contemporary papermaking fabrics are produced in a wide variety of styles designed to meet the requirements of the paper machines on which they are installed for the paper grades being manufactured. Generally, they comprise a woven base fabric. The base fabrics may be woven from monofilament, plied monofilament, multifilament or plied multifilament yarns, and may be single-layered, multi-layered or laminated. The yarns are typically extruded from any one of the synthetic polymeric resins, such as polyamide and polyester resins, used for this purpose by those of ordinary skill in the paper machine clothing arts.
The woven base fabrics themselves take many different forms. For example, they may be woven endless, or flat woven and subsequently rendered into endless form with a woven seam. Alternatively, they may be produced by a process commonly known as modified endless weaving, wherein the widthwise edges of the base fabric are provided with seaming loops using the machine-direction (MD) yarns thereof. In this process, the MD yarns weave continuously back-and-forth between the widthwise edges of the fabric, at each edge turning back and forming a seaming loop. A base fabric produced in this fashion is placed into endless form during installation on a paper machine, and for this reason is referred to as an on-machine-seamable fabric. To place such a fabric into endless form, the two widthwise edges are brought together, the seaming loops at the two edges are interdigitated with one another, and a seaming pin or pintle is directed through the passage formed by the interdigitated seaming loops.
Further, the woven base fabrics may be laminated by placing at least one base fabric within the endless loop formed by another, and by needling a staple fiber batt through these base fabrics to join them to one another. One or more of these woven base fabrics may be of the on-machine-seamable type. This is now a well known laminated press fabric with a multiple base support structure.
In any event, the woven base fabrics are in the form of endless loops, or are seamable into such forms, having a specific length, measured longitudinally therearound, and a specific width, measured transversely thereacross.
Traditional press sections include a series of nips formed by pairs of adjacent cylindrical press rolls. Recently, the use of long press nips has been found to be advantageous over the use of nips formed by pairs of adjacent rolls. The longer the web can be subjected to pressure in the nip, the more water can be removed there, and, consequently, the less will remain to be removed through evaporation in the dryer section.
In long nip presses of the shoe type variety, the nip is formed between a cylindrical press roll and an arcuate pressure shoe. The latter has a cylindrically concave surface having a radius of curvature close to the cylindrical press roll. When roll and shoe are brought into close physical proximity, a nip is formed which can be five to ten times longer in the machine direction than one formed between two press rolls. This increases the so-called dwell time of the fibrous web in the long nip while maintaining the same level of pressure per square inch pressing force used in a two-roll press. The result of this long nip technology has been a dramatic increase in dewatering of the fibrous web in the long nip when compared to conventional roll nips on paper machines.
A long nip press of the shoe type requires a special belt. This belt is designed to protect the press fabric supporting, carrying, and dewatering the fibrous web from the accelerated wear that would result from direct, sliding contact over the stationary pressure shoe. Such a belt must be made with a smooth impervious surface that rides, or slides over the stationary shoe on a lubricating film of oil. The belt moves through the nip at roughly the same speed as the press fabric.
Belts of such variety are made, for example, by impregnating a woven base fabric, which takes the form of an endless loop, with a synthetic polymeric resin. Preferably, the resin forms a coating of some predetermined thickness on the inner surface of the belt, so that the yarns from which the base fabric is woven may be protected from direct contact with the arcuate pressure shoe component of the long nip press.
It is often desirable to provide the belt with a resin coating of some predetermined thickness on its outer surface as well as on its inner surface. Moreover, when the outer surface of the belt has a resin coating of some predetermined thickness, it permits grooves, blind-drilled holes or other cavities to be formed on that surface without exposing any part of the woven base fabric. These features provide for the temporary storage of water pressed from the web in the press nip. In fact, for some long nip press configurations the presence of some void volume, provided by grooves, blind-drilled holes or the like, on the outer surface of the belt is a necessity.
The present invention relates to shoe press belts having a plurality of grooves and rebates in the machine direction located in the resin coating on the outer surface thereof. | {
"pile_set_name": "USPTO Backgrounds"
} |
The therapeutic use of rapid bodily cooling systems is ever-increasing. Of particular interest, it is now accepted that rapid cooling of stroke, cardiac arrest and head trauma patients can yield significant therapeutic benefits. Specifically, research indicates that even though a stroke or cardiac arrest victim's brain cells may loose their ability to function, the cells do not necessarily die quickly. In fact, brain damage from a stroke or cardiac arrest may take hours to reach maximum effect. Neurological damage may be reduced and the stroke or cardiac arrest victims' outcome improved if a neuroprotectant therapy is applied within this time frame.
Similarly, elements in the genesis of a traumatic brain injury (e.g., resulting from falls, vehicular accidents and the like) are now understood to overlap with elements in the genesis of neurological damage in stroke victims. In particular, delayed secondary injury at the cellular level after the initial head trauma is now recognized as a major contributing factor to the ultimate tissue loss that occurs after brain injury. Again, neurologic damage may be reduced if a neuroprotectant therapy is rapidly applied. Further, in this regard, studies have shown that treatment with mild hypothermia, defined as lowering core body temperature at 2-3 C.° confers neuroprotection in stroke victims, and may hasten the neurologic recovery and improve outcomes when applied for 12-72 hours in cases of traumatic head injury. Again, to optimize such therapies, the neuro-protective therapy should be initiated as soon as possible after a stroke or traumatic head injury.
As these and other medical applications for rapid bodily cooling have continued to evolve, the present inventors have recognized the desirability of enhancing the portability, stowability and ease-of-use of patient cooling systems so that patient treatment may be promptly initiated. More particularly, while known patient cooling systems have proven effective for many applications, the present inventors have recognized that additional emergency-oriented applications can be realized via the implementation of further improved liquid cooling methodologies and stand-alone componentry, as well as enhanced componentry packaging. In this regard, the present inventors have recognized the need for a cooling system and related methodology that is particularly apt for use in ambulatory settings, including, in particular, use in emergency vehicles such as helicopters, ambulances and the like where space utilization is at a premium and patient access may be limited. | {
"pile_set_name": "USPTO Backgrounds"
} |
In networks, a plurality of routers relay a packet and transmit it to a destination computer. Each router exchanges route information with other routers in order to recognize transmission routes to the destination of the packet. The route information includes a transmission route which a router that sends the route information recognizes. Each router selects a packet transfer destination on the basis of the route information received from the other routers.
If there are a plurality of transmission routes from a router to a destination computer, then the router performs route selection in accordance with a predetermined algorithm. A route selection algorithm used by each router is provided in a routing protocol such as OSPF (Open Shortest Route First) or RIP (Routing Information Protocol). With these routing protocols, basically route selection is performed so that the shortest route will be taken. Alternatively, the existing advanced control using these routing protocols is exercised. That is to say, smoothing is performed so that the peak of network usage will be minimized. At the same time route selection is performed so that the shortest route will be taken.
If the above conventional routing protocols are used, traffic such as a packet is transmitted along a predetermined route. Accordingly, even when a traffic volume is low throughout a network, it is necessary to continue starting each router.
With the improvement of network throughput, on the other hand, the consumption of power by devices included in networks has increased. Therefore, the operation which controls the power consumption of an entire network is important. As a result, the following technique is proposed. A network controller monitors the state of traffic in a communication network. When a traffic volume is low, the traffic is transmitted along a detour. As a result, a part of routes is used and switching systems can be stopped. This procedure can save electric power (see Japanese Laid-open Patent Publication No. 2001-119730).
In some networks, however, it is difficult to exercise centralized traffic control by a management system. In a large-scale network, for example, it is difficult to exercise centralized control of all traffic by a management system. In addition, if centralized traffic control is exercised on each transmission route by a management system, the influence of trouble, such as a system malfunction, may spread throughout a network. This leads to a deterioration in the reliability of an entire system. | {
"pile_set_name": "USPTO Backgrounds"
} |
It is said that the cure rate in cancer treatment is about 50%. at present, and generally, such cure is brought about often by topical therapy such as surgical therapy and radiotherapy. It is in a very low rate that chemotherapy as systemic therapy can contribute solely to cue, particularly in treatment of solid tumor, and usually chemotherapy is used in combination with various therapies.
On the other hand, surgical therapy enables surgery in every organ cancer and is considered to reach completion as therapy, and no further improvement in cure rate can be expected. The treatment results of susceptible organ cancers by radiotherapy also arrive at an almost fixed rate, and no further improvement in cure rate can be expected as well.
Accordingly, no significant improvement in cancer cure rate by these therapies can be expected in the future, and the development of further excellent chemotherapy is essential for further improving the cancer cure rate of 50% at present to arrive at cure for cancer.
An purpose of an anticancer agent used in chemotherapy lies in cytocidal effect on cells having a high ability to grow, such as cancer cells, and its damage to normal cells particularly myeloid cells having a high cellular growth ability is significant, and as a result, severe pain is given to patients. This is because the transfer of the anticancer agent is due to systemic administration by an injection, and the anticancer agent reaches normal cells other than cancer cells, so that the normal cells are killed and homeostasis does not function.
At present, however, the effect of an anticancer agent administered alone is regarded to be approximately about 30%, and it is expected that genetic information analysis and study on genome proceed so that selection of a suitable anticancer agent feasible can be expected in the future, but it is said that the therapy with the anticancer agent at present results in higher side effects.
This is because normal cells are damaged by systemic administration of an anticancer agent. Accordingly, if cancer tissue-specific delivery of the anticancer agent and subsequent incorporation thereof into cancer cells can be established, an ideal system of delivering the anticancer agent can be realized. In addition, if incorporation of the anticancer agent into a vesicle is feasible, a therapeutic method that is specific for target organ and cell with less influence (side effect) on normal cells can be established. Further, this can lead to reassessment of anticancer agents whose development was abandoned because of their strong side effects. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
This invention relates to cooking apparatuses, and in particular, to a beverage can cooking apparatus for roasting chickens, turkeys, ducks, birds, etc. (hereinafter for the specification and claims all collectively referred to as xe2x80x9cchickenxe2x80x9d orxe2x80x9cchickensxe2x80x9d).
2. Description of Related Art
When cooking chickens and the like, it is not uncommon for the chicken to lose its moisture due to the relatively long exposure of the chicken to high temperatures during the cooking process. An internal cavity for the chicken can be created prior to or after the purchase of the chicken by the consumer. Thus, devices have been used in the past to act as a stand for the chicken and also allow for steam to be introduced into the internal cavity during cooking to prevent drying of the chicken. These stands typically include tube or cone like members attached to a base. The tube or cone is inserted within the internal cavity of the chicken. The tube or cone typically consist of a perforated wall member.
Examples of these structures include U.S. Pat. No. 5,106,642 issued to Ciofalo for a Roasting Support for Fowl; U.S. Pat. No. 6,125,739 issued to Jernigan for a Device for Supporting and Steaming Fowl; U.S. Pat. No. 5,301,602 issued to Ryczek for a Fat-Free Roaster for Poultry and Meat; U.S. Pat. No. 6,062,131 issued to Holland for a Roasting Stand Adapted to Deliver Flavored Steam During the Cooking Process; U.S. Pat. No. 5,893,320 issued to Demaree for a Device for Cooking Fowl; and U.S. Pat. No. 4,709,626 issued to Hamlyn for a Foldable Chicken Holder.
To permit steam to be introduced back into the chicken, the prior art has provided relatively complicated structures. One method known for cooking chicken is in conjunction with a beverage can, such as partially filled beer can. None of the prior art devices discussed above provide a structure for properly positioning a beverage can, at least partially within the cavity of the chicken, to allow the moisture from the liquid disposed within the can to be released into the cavity to keep the chicken moist.
It is therefore to the effective resolution of the aforementioned problems and shortcomings that the present invention is directed.
The present invention provided a cooking apparatus, including a can retainer, for cooking chickens. The apparatus includes two preferably xe2x80x9cUxe2x80x9d shaped members pivotally attached to a base member. Base member is preferably circular in shape, though such is not considered limiting. A first of the two xe2x80x9cUxe2x80x9d shaped members is slightly longer in length that the second xe2x80x9cUxe2x80x9d shaped member, such that, when in use, the larger first xe2x80x9cUxe2x80x9d shaped member rides over the second xe2x80x9cUxe2x80x9d shaped member. When the xe2x80x9cUxe2x80x9d shaped members begin to reach their xe2x80x9cin usexe2x80x94assembledxe2x80x9d position they begin to abut.
A small groove, notch or other indentation is preferably provided at the top or apex of the second xe2x80x9cUxe2x80x9d shaped member. Thus, when assembling the cooking apparatus for use, the first xe2x80x9cUxe2x80x9d shaped member rides over the second xe2x80x9cUxe2x80x9d shaped member until the first member drops into the groove, where it is securely retained to maintain the xe2x80x9cUxe2x80x9d shaped members in their assembled vertical position during use. The size of the groove is at least large enough to receive enough of a cross-sectional portion of the first xe2x80x9cUxe2x80x9d shaped member to securely retain the first member during use of the invention.
A can holder is provided and in one embodiment movably attached to the second xe2x80x9cUxe2x80x9d shaped member and in a second embodiment permanently attached to the second xe2x80x9cUxe2x80x9d shaped member. In one movable embodiment, can holder can be shaped as an elongated bar having an aperture at each end for receipt therethrough of the second xe2x80x9cUxe2x80x9d shaped member. Other shapes for the can holder can be provided and are considered within the scope of the invention. In its assembled position, the can holder is preferably located toward the bottom of the cooking apparatus to support the can from the bottom. In a permanent embodiment, the can holder can be a circular bar attached to the second xe2x80x9cUxe2x80x9d shaped member at two separate points. Other shapes and configurations can also be used for the permanent embodiment and are all considered within the scope of the invention.
Though a can, such as a twelve ounce beer can is preferred, the present invention is not limited to such, and other objects that hold liquid can be used in lieu of a beer can, such as a glass, cup, bottle, etc. The present invention cooking apparatus can be used with various heating elements, such as but not limited to kettle grills, gas grills, ovens, etc.
When not in use the cooking apparatus is collapsed or folded for ease in storage or transit by popping first xe2x80x9cUxe2x80x9d shaped member out of its resting position within the groove of the second xe2x80x9cUxe2x80x9d shaped member. Such effort to remove the first member out of the groove of the second member can be provided by a small amount of force from the user.
Accordingly, it is an object of this invention to provide a cooking apparatus that permits moisture to be provided to a chicken during cooking.
It is another object of the invention to provide a cooking apparatus that positions a beverage can within the internal cavity of a chicken while cooking the chicken.
It is still another object of this invention to provide a cooking apparatus that positions a beverage can within the internal cavity of a chicken while also serving as a stand for the chicken.
It is yet another object of this invention to provide a cooking apparatus that positions a beverage can within the internal cavity of a chicken to introduce moisture into the cavity during cooking of the chicken.
It is even still another object of the invention to provide a cooking apparatus that positions a beverage can within the internal cavity of a chicken while cooking the chicken where the apparatus is collapsible or foldable. | {
"pile_set_name": "USPTO Backgrounds"
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The Internet is rapidly becoming a global community of information exchange. This growth in connectivity, coinciding with the evolution of hand held devices makes Internet connectivity and socialization a growing part of our immediate, everyday lives. Evolving Social Networks, search engines and the ability to share personal opinion through community platforms are creating an increasing social complexity and a glut of social data and information that is challenging the effectiveness of the Internet's open-source architecture. This requires certain systematic standards that recognize the value of online Users and the information they share in order to provide more meaningful connections between people and information.
Within the context of a single Social Network, most people are familiar with the natural and free flowing exchanges and discussions that tend to develop. Whether the topic of discussion be that of endurance sports, surfing, pets, gardening, cooking, survival tactics, dating, wine & cheese, education, business, politics or just about anything, there seems to be no shortage of people willing to offer comment and suggestion.
Yet there is no standard in place for valuing people and the information they share. Therefore, recipients or later readers of such a discussion are left entirely to their own assessment for evaluating who is and is not a valid contributor. In addition, although there is a vast amount of information provided by most Social Networks, it is often very difficult for a person to discover posts, discussions, communities, or even just other Users who either share similar views or perhaps may be a credible and valuable resource for learning something new.
More specifically, a comment about surfing locations, boards or wax may well be offered by a life time surfer who truly knows his or her stuff, or a land locked person who has never seen the ocean and despises the surfing culture. The simple use of terms related to Surfing by the primary author is not really sufficient by itself to establish the author as an authority, and a simple searching on those terms may or may not result in helpful identification of that author as a good source for surfing information.
As users become more reliant upon search engines to find information, it is very desirable for the search engines to be more accurate in identifying the meaning of search criteria. Likewise there is a growing need for social networks to provide more meaningful connections between people and information. The challenge lies in understanding such an expression as “Hot Dog.” Does this mean the food, a canine with an elevated blood pressure or an expression of amazement? Likewise the word “Jaguar” could be a jungle cat, a luxury vehicle or the NFL sports team from Jacksonville. Misunderstanding the context of association between the terms may and often does, result in erroneous search results.
In some cases, search engines permit a search wherein a first term is used within X words or characters of a second term. Though perhaps helpful for identifying specific documents or articles, this methodology does not scale to groups of discussion, articles, communities or other related entities and still may not recognize the context as intended by the author. Moreover, such search systems are constructed with the view that if terms exist within proximity to each other they must be related—but this is not always the case. In addition, such methodology is focused strictly on the relationship of the terms with respect to each specific document and can not and does not permit a greater awareness of the relationship of the terms in a greater context.
Though perhaps an extreme example, the issues of identifying similarities with other Users or Entities such as posts, discussions, or other online communities may be quite important when a parent is looking for safe birthday ideas for children, advice on nut allergies or other issues where misguided responses or even intentionally malicious responses could pose actual harm.
The frustrations with a single site are appreciated to compound when looking at multiple sites. A User very qualified for a particular subject, say marathons, may be entirely new to a site and therefore even regular contributors may not recognize him or her, let alone appreciate that there are interests in common Nor will this User be able to find the Entities i.e. other Users, posts, discussions, or other communities that suit his varying degrees of interest.
Subsequently the ability to authentically recognize credible and reliable sources that relate to specific subjects of interests not only benefits the end User, but also communities, institutions, governments and all forms of organizations by enhancing semantic and social analytics, consumer trends, ad targeting, market and product analysis, while providing a more viable source for ratings, feedback and reviews.
In essence, the open-architecture of the Web requires a better standard for providing the right information to the right people at the right time. A system that generates authentic credentials and establishing accurate similarities, as a means to filtering information or controlling privacy, visibility, and connectivity between people and information, would serve the best interest of the people and organizations that use the Web. The lack of an authentic social standard has resulted in misinformation, intrusive advertising, threats to privacy, and malicious behavior by unwanted, trolling individuals over open forums and discussions.
Due to these concerns, the Web is still unsafe when it comes to the open exchange of knowledge and information, therefore, private institutions such as enterprises, schools, universities, governments, or other organizations, are reluctant to embrace open social integration that would benefit their cause (i.e. research and development, training, education, job placement, cross-platform communication, community management, social integration, etc.)
Since the Internet is an open-source architecture, Web social organization is beyond the scope of conventional approaches to social organization and this presents an extremely complex situation to network based (e.g., Internet) Social Networking organization.
What is necessary is a systematic standard for establishing online credentials in order to recognize the similarities between the various parts of social networking, i.e. the keywords, the people, their posts, the discussions, the communities, groups, etc., thus providing privacy and safety through better organization between the different elements of the social Web.
Hence there is a need for a method and system of determining similarities between Entities that is capable of overcoming one or more of the above identified challenges. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates to a rolled copper foil, more particularly, to a rolled copper foil to be used for a flexible printed circuit (FPC) or the like.
2. Description of the Related Art
The FPC is provided with a high degree of freedom in mounting morphology for electronic device or the like, since the FPC has a reduced thickness and superior flexibility. Therefore, the FPC has been used for a bending part of a folding type portable phone, a movable part of digital camera, printer head or the like, an electric wiring of a movable part of disc-related equipment such as Hard Disk Drive (HDD), Digital Versatile Disc (DVD), Compact Disk (CD).
Japanese Patent Laid-Open No. 2002-167632 (JP-A 2002-167632) discloses one example of conventional rolled copper foils for a flexible printed circuit having a following configuration.
Namely, the rolled copper foil for a flexible printed circuit contains oxygen (O) of 100 to 500 mass ppm, and contains at least one element selected from a group consisted of silver (Ag), gold (Au), palladium (Pd), platinum (Pt), rhodium (Rh), iridium (Ir), ruthenium (Ru), and osmium (Os) in the ranges so as to control T defined by the following formula to 100 to 400: T=[Ag]+0.6[Au]+0.6[Pd]+0.4[Pt]+0.4[Rh]+0.3[Ir]+0.3[Ru]+0.3[Os] (wherein, [M] is the mass ppm concentration of the element M), and in which the total content of sulfur (S), arsenic (As), antimony (Sb), bismuth (Bi), selenium (Se) and tellurium (Te) is 30 mass ppm or less. The rolled copper foil has a thickness of 5 to 50 μm. The intensity (I) in the 200 plane obtained by X-ray diffraction for the rolled face after annealing at 200° C. for 30 min to the intensity (I0) in the 200 plane obtained by X-ray diffraction for the pulverized copper, i.e., I/I0 is >20. The rolled copper foil has a semi-softening temperature of 120 to 150° C., and continuously maintains tensile strength of ≧300 N/mm2 at a room temperature.
According to the above structure, the rolled copper foil for a flexible printed circuit disclosed by JP-A 2002-167632 has a superior bending-fatigue life characteristic.
However, in the rolled copper foil for a flexible printed circuit disclosed by JP-A 2002-167632, when oxide is generated from the oxygen (O) contained in this copper foil, there is the case that this oxide may become an origin of fatigue breakdown. Therefore, there is a limit for enhancement of the bending-fatigue life characteristic according to this structure.
Further, in the case of using the oxygen free copper containing substantially no oxide, since a softening temperature (apparent initial softening) of the oxygen free copper per se is higher than that of copper containing oxygen (O) (of 100 to 500 mass ppm), progression of recrystallization in the copper foil is insufficient under low temperature condition (e.g. 160° C.). Therefore, a good bending-fatigue life characteristic cannot be provided. Further, if additive elements disclosed by JP-A 2002-167632 is used in the copper, the softening temperature of the copper will be further raised. Therefore, the addition of the additive elements is advantageous under a high temperature condition (e.g. 400° C.). However, the copper containing such additive elements cannot be used under the low temperature condition. Still further, if no additive element is added to the oxygen free copper, there will be no affect of the oxide. Therefore, the progression of recrystallization advances in the copper foil appropriately under the low temperature condition, so that a good bending-fatigue life characteristic is provided. On the other hand, there is the case that the bending-fatigue life characteristic falls because the recrystallization advances excessively in the copper foil under the high temperature condition. Therefore, it is not possible for the conventional rolled copper to correspond to heat treatment in a wide temperature range. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
The field of the present invention relates to electronic hardware, including virtual, component design. In particular, the field of the present invention relates to the interfaces between components.
2. Background
The methodologies for designing, testing and manufacturing integrated circuits (ICs) continue to evolve. Today, with the continually increasing complexity and density of ICs, designing for reusability is becoming an overriding priority. One consequence of this priority is the increasing distinction of between the developers of potentially reusable functional component blocks, that when used with each other provide the foundation for an IC or the design of an IC, and the integrators of such blocks. A number of companies focus on the development of such functional block components. Some of the same companies as well as many others perform the integration and/or manufacturing of the ultimate ICs.
One of the new developments in circuit designs is the advent of so-called virtual component blocks, which, from a general standpoint, are pre-designed and pre-hardened (or semi-hardened) circuit designs in software form (for example, in GDSII format), which can be readily re-used or recycled in different, larger circuit designs. An advantage of virtual component (or VC) blocks is that they reduce the time to design an overall circuit, and thereby, increase the speed to market.
The breakdown of IC development into the design of discrete functional components, and the fact that there are many providers of such components, has in part been responsible for the creation of a need to have a standard interface for communicating between components. This is one of the goals of the Virtual Socket Interface Alliance (VSIA) Virtual Component Interface (VCI) Standard. A draft of this standard, Standard 2 Version 1.0 (Working Revision (Feb. 2, 2000) is attached as an appendix. To meet this stated goal, which includes objectives of connectability, flexibility, and portability of component blocks, the VCI protocol, as outlined in the specification, has been developed with an eye towards simplicity.
A preference for simplicity in the VCI protocol, in turn, has necessarily led to certain requirements to which component blocks that adopt the protocol must adhere. A first requirement is that one side of the interface is required to act as a master or initiator of a communication and the other side is required to act as a slave or target for the communication. As such, the design of the target interface has inherent differences from that of the initiator interface. Specifically, each side of the interface, by definition, comprises different logic to enable each side to perform its predefined role in the communication. Because of these complementary functions, the inputs and outputs on each side of the interface are also different from each other. The pins on each side of the interface to which connections are made represent a type of signal input or output that is generally specific to that side of the interface.
Another requirement is that the VC Interface of a functional block be a unidirectional interface. Output pins on one side of the interface are connected to input pins on the other side of the interface, such that signals travel in only one direction for a given connection.
Thus, functional components (including virtual components (VCs)) that include a VC interface can act only as targets or initiators in a point-to-point communication. As such, in any communication between two components, if one component is defined as a master, the other must be a slave, and vice versa.
In any methodology for designing ICs based on predefined component blocks, one of the first steps is to specify, as a starting point, the component blocks that will be used as the foundation of the design. One such component block that is identified at this stage is the foundation block, a block that typically comprises a processor, some memory and a communication block. The communication block has the primary purpose of transferring data from one place to another, an in the context of IC design includes a bus connected to multiple I/O ports. The foundation block often manages the communication between most if not all of the other component blocks to be used in the IC. Because it includes a communication block, the foundation block typically includes on its edges a large number of ports, of which some are initiators and others are targets. Because of the requirements of standard protocols such as the VCI protocol, the type of interface at a particular location on the edge of a foundation block must be predefined. Thus, characterizing the foundation block that is to be used for a given IC typically requires specifying a bus and the number, locations and types of ports on the edges of the block. For example, one common layout of ports for a foundation block is to position them evenly around the foundation block to provide for floor-planning flexibility.
One of the next steps is specifying the placement of the component blocks, including the foundation block, to form the layout of the IC. In this process, chip designers try to minimize wire lengths between pins of different components and minimize the overall area or footprint of the IC. Increasingly, these connection distances are the greatest speed-limiting factor in efforts to increase the speed and performance of an IC.
To assist in optimizing the layout of the IC, chip designers often use electronic design automation (EDA) software tools. The component blocks are automatically “placed” (i.e., given specific coordinate locations in the circuit layout) and “routed” (i.e., wired or connected together according to the designer's circuit definitions). The placement and routing software routines generally accept as their input a flattened netlist that has been generated by a prior logic synthesis process. This flattened netlist identifies the specific components from a component library, and describes the specific component-to-component connectivity. After this specific connectivity has been established, the physical design and layout software creates a physical layout file of the integrated circuit, including the physical position of each metal line (i.e., wire) and each via (i.e., metal transition between chip layers).
Further explanation of a particular chip design process is set forth, for example, in U.S. Pat. No. 5,838,583, hereby incorporated by reference as if set forth fully herein.
Because the ports for the foundation block are specified before the layout process can be performed, the flexibility in component block placement is potentially limited by the locations and types of ports that have been specified. Essentially, the capability of optimizing a design footprint or achieving minimum connection lengths, and thereby, the IC's overall speed and performance, is compromised.
A need exists therefore, for a way of optimizing for speed and performance in an electronic design without incurring the limitations inherent in a predefined foundation block or other functional block. | {
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FIELD OF THE INVENTION
The invention relates to an electrical conductor having a longitudinal direction and a stacking direction perpendicular to the longitudinal direction, which can be stacked with a plurality of identical conductors with the interposition of an insulating layer between each two adjacent conductors, the conductor having two substantially flat main sides oriented perpendicular to the stacking direction and having at least a set or multiplicity of slots being disposed in succession approximately in the longitudinal direction, each leading approximately in the stacking direction through the conductor and having a mouth in each main side.
Such electrical conductors find many uses in windings of electrical machines, particularly in the windings of turbo generators that are cooled with a coolant gas, in particular air or hydrogen, in order to dissipate the heat produced during operation. Electrical conductors of that type, like their use in the windings of electric machines, are described in a book entitled "Herstellung der Wicklungen Elektrischer Maschinen" [Manufacture of the Windings of Electrical Machines], edited by H. Sequenz, Springer Verlag, Vienna and New York 1973, particularly in an article by D. Lambrecht contained in that book and entitled "Lauferwicklungen fur Turbogeneratoren" [Rotor Windings for Turbogenerators] (page 169 ff.). In order to select the material for an electrical conductor of the type described, reference may be made in particular to an article that is also contained in that book, entitled "Leiterwerkstoffe" [Conductor Materials] by R. Knobloch (page 1 ff.). An example of the use of an electrical conductor of that kind may be found in European Patent No. 0 160 887 B1.
As described in detail particularly in the article by D. Lambrecht, electrical conductors of the type described are typically stacked one above the other in a stacking direction perpendicular to the longitudinal directions of the electrical conductors in order to form a winding for an electrical machine, optionally using intermediate insulating layers. Slots in electric conductors and insulating layers that are adjacent to one another are made to overlap at least partially with one another, so that they communicate among one another to form cooling conduits leading through the stacked electrical conductors. The cooling conduits are oriented substantially parallel to a plane defined by the mutually parallel longitudinal directions and by the stacking direction. During operation of the winding, the cooling conduits are flooded with coolant gas, in particular air or hydrogen, as is explained in detail in the references cited.
German Published, Prosecuted Application DE-AS 1 242 744 and German Patent DE-PS 1 242 744 describe an electrical conductor with a longitudinal direction and a stacking direction perpendicular to the longitudinal direction, which can be stacked with a plurality of identical conductors in the stacking direction, and in which at least one insulating layer is to be inserted between each two conductors. The conductor is defined by two substantially flat main sides being oriented perpendicular to the stacking direction and having a set of slots, which are disposed in succession approximately in the longitudinal direction and each of which leads in the stacking direction through the conductor and has a sharp-edged mouth in each main side. At boundary edges, each slot has groove-like milled cuts, which are filled by bush-like adapter pieces of insulating material when this conductor is stacked together with other conductors.
U.S. Pat. No. 4,152,610 discloses a stackable electrical conductor with a set of slots that lead in a stacking direction through the conductor which has a longitudinal groove, oriented parallel to a longitudinal direction of the conductor, for forming a coolant conduit.
German Published, Non-Prosecuted Application DE-OS 1 438 335 describes a stack of electrical conductors being insulated from one another by insulating layers with slots oriented in the stacking direction, in which a slot of a conductor communicates with a slot of an adjacent conductor through a conduit oriented at an angle to a common longitudinal direction of the conductors. Such a conduit may be made in the insulation and/or in one of the conductors.
When the slots are produced in the electrical conductors, special care and therefore in accordance with current practice expensive post-machining of the stamped or milled slots is necessary, as is explained in detail in the article by D. Lambrecht cited above, among other sources, in order to avoid undesired electrical connections in the form of short circuits and the like between two electrical conductors resting on one another and between which there is only a thin insulating layer. Therefore, conventionally the mouths of the slots must be deburred and rounded off or beveled by subsequent countersinking, embossing or the like, which despite the attendant effort and especially the attendant expense is considered too important to be omitted. | {
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The invention relates to a hybrid drive train for a motor vehicle, having an internal combustion engine for making available internal-combustion-engine drive power, a multi-step transmission having a transmission input and a transmission output, wherein the transmission input can be connected to the internal combustion engine, and wherein the multi-step transmission is designed to set up a multiplicity of different forward gear ratios, and an electric machine for making available electromotive drive power.
In addition, the present invention relates to a motor vehicle having such a hybrid drive train, and to a method for carrying out a gear change in a hybrid drive train.
Hybrid drive trains for motor vehicles are known in different embodiments. In many hybrid drive trains an electric machine is connected to a transmission input. Hybrid drive trains of this type permit the electric machine to be used for boosting or else for purely electric drive. In this case, all the forward gear ratios of the multi-step transmission can be used in the electric driving mode. However, in this case the electric machine cannot be used to make available tractive force assistance during gear changes. This is possible in such hybrid drive trains in which the electric machine is connected to the output of the multi-step transmission. However, in this case a purely electric driving mode can be used only with a single transmission ratio. In addition, charging in the stationary state (using the electric machine as a generator for charging an electric energy store when the vehicle is stationary) is generally not possible.
In addition, hybrid drive trains are also known in which the multi-step transmission is embodied as a double-clutch transmission. Such transmissions in themselves already permit a gearshift without interruption of the tractive force. In this context it is known, for example, to connect an electric machine to one of the two component transmissions of such a double-clutch transmission, generally to the transmission input. However, hybrid drive trains of this type are very complex and many functions are carried out in duplicate.
Document DE 197 47 265 A1 discloses a hybrid drive train in which no separate gear set for the reverse driving mode is set up in the multi-step transmission, with the result that reverse travel is only possible by means of an electric motor.
Document DE 10 2005 048 938 A1 discloses a hybrid drive train having a double-clutch transmission, wherein an electric machine can be effectively connected both to a first and a second input shaft via an additionally provided transmission.
Document EP 1 972 481 A1 discloses a hybrid drive train in which a gear-shift component transmission has an input shaft and an output shaft, wherein, for example, uneven gear ratios are assigned to the first component transmission. In addition, the drive train contains a second gear-shift component transmission having an input shaft and an output shaft, wherein, for example, the even gear ratios are assigned to this component transmission. The input shaft of the first gear-shift component transmission can be coupled to the internal combustion engine via a starter clutch. The input shaft of the second gear-shift component transmission has a drive connection to the electric machine. In addition, the two input shafts can be connected to one another in a rotationally fixed fashion via a coupling unit.
Finally, document DE 196 12 690 C1 discloses a drive train having an automated transmission which is embodied as a range-change transmission with a first transmission group and a downstream second transmission group. | {
"pile_set_name": "USPTO Backgrounds"
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Field of the Invention
The invention concerns a method for creating at least two essentially parallel two-dimensional image data sets of a region of interest by operation of a magnetic resonance system having a coil array.
Description of the Prior Art
A basic problem for acquiring MR images is the scan time. This was initially reduced by software methods in the form of optimized pulse sequences, wherein the flip angle of the pulses, the number thereof, the setting of the gradients or the waiting times between individual sequence sections, was modified. It was thus possible to reduce the acquisition of a gradient echo image using the FLASH method from several minutes to a few seconds. Although this changes the contrast behavior, it remains T2*-dependent. The RARE method is well-known as a fast, spin echo based imaging method. Other methods such as GRASE or TrueFISP exist, which constitute a form of mixture of the basic methods.
In order to achieve a further reduction in the acquisition time, it has been proposed to use multiple coils for reading out the scan signal. Not all the k-space lines are acquired but only selected ones, but using the multiple coils. This is also known as undersampling. In order to prevent an aliasing artefact, i.e. foldover effects, that are caused by this procedure in the reconstructed image, different reconstruction algorithms are used that manage with fewer k-space lines and therefore the more time-consuming scanning (filling) of the k-space lines is unnecessary.
Such reconstruction methods are commonly referred to under the acronyms GRAPPA (GeneRalized Autocalibrating Partially Parallel Acquisition), SENSE (SENSitivity Encoding for fast MRI) and SMASH (SiMultaneous Acquisition of Spatial Harmonics).
In the case of SENSE, first presented in SENSE: sensitivity encoding for fast MRI. Pruessmann K P, Weiger M, Scheidegger M B, Boesiger P, Magn Reson Med., 42(5), 952-62, 1999, the coil sensitivities are measured and a pseudoinverse matrix is determined therefrom. Using this matrix, the acquired image data of all the coils is combined into a full image. In other words, the coil images are unfolded to produce a total view.
In the case of the GRAPPA reconstruction method, the missing k-space lines are reconstructed by determining a k-space line to be added from a number of scanned k-space, lines by mathematically shifting the measured signal in k-space.
These reconstruction methods are based on the fact that the coil sensitivities differ in the region of interest. In order to amplify or rather make optimum use of these sensitivity variations, several methods collectively referred to under the acronym CAIPIRINHA (Controlled Aliasing In Parallel Imaging Results IN Higher Acceleration) are known. These are based on the fact that the aliasings can be selectively varied during data acquisition.
In the case of MS-CAIPIRINHA (Felix A. Breuer, Martin Blaimer, Robin M. Heidemann, Matthias F. Mueller, Mark A. Griswold, and Peter M. Jakob: Controlled Aliasing in Parallel Imaging Results in Higher Acceleration for Multi-Slice Imaging, Magn. Res. Med. 53:684-691, 2005), two slices are excited by alternating dual band pulses.
2D-CAIPIRINHA (Felix A. Breuer, Martin Blaimer, Matthias F. Mueller, Nicole Seiberlich, Robin M. Heidemann, Mark A. Griswold, and Peter M. Jakob: Controlled Aliasing in Volumetric Parallel Imaging, Magn. Res. Med., 55:549-556, 2006) is based on improving sensitivity variations for three-dimensional imaging in the phase encoding directions then present in two spatial directions.
In blipped CAIPIRINHA (Blipped-Controlled Aliasing in Parallel Imaging for Simultaneous Multislice Echo Planar Imaging With Reduced g-Factor Penalty. Kawin Setsompop, Borjan A. Gagoski, Jonathan R. Polimeni, Thomas Witzel, Van J. Wedeen, and Lawrence L. Wald), the slice gradient is additionally switched in the form of blips, i.e. in an oscillating manner, during readout.
Although the sensitivity changes produced in CAIPIRINHA must be taken into account for the reconstruction methods, the usual and above mentioned methods, such as GRAPPA and SENSE, can be used. CAIPIRINHA changes the evaluation by the reconstruction taking place as if coils having other sensitivities were present.
For data acquisition, well-known methods such as TrueFISP can also be used for CAIPIRINHA. The difference lies in the number of acquired k-space lines and the sensitivity variation.
For acquisition of a three-dimensional volume, either three-dimensional data sets can be acquired. These have two phase encoding directions and their acquisition is time-consuming even when using parallel imaging. Or, for time-critical examinations, it is therefore preferable to acquire two-dimensional images in a plurality of slices. This is also known as multislice imaging. This type of data acquisition can also be speeded up using parallel imaging, cf. the remarks concerning MS-CAIPIRINHA.
In the case of spin echo methods, the slices can be acquired intermittently, i.e. one or more k-space lines of successive slices. This is repeated until a sufficient set of k-space lines is present in each slice.
Alternatively, each slice can also be acquired completely before the next follows. This is particularly the case for acquisition methods such as FLASH or TrueFISP or bSSFP (balanced steady state free precession).
The slices acquired in this way have therefore been acquired at different points in time. In the case of moving examination objects such as the heart or lung, the image data of the different slices are shifted relative to one another and must therefore be registered to one another in order to be able to create a 3D-image therefrom. For registration of the images, a high SNR is advantageous, for which reason bSSFP is preferred. However, with this type of data acquisition the achievable contrast is limited to the contrast obtained by means of bSSFP. This is a mixed contrast which depends on T1 and T2.
If the image data sets are to have other contrasts, it is possible, particularly in the case of moving examination objects, to register the scan signals using navigator echoes. However, the disadvantage of this is that the navigator echoes interrupt the sequence progression and the motion is characterized on the basis of few values, i.e. the characterization is prone to errors. | {
"pile_set_name": "USPTO Backgrounds"
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The discussion below is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter.
Aspects of invention relate to an open roof construction for a vehicle, comprising a roof opening defined in a stationary roof part and a movable panel for opening and closing said roof opening, with a slide which is movable along a stationary slide guide and which is provided with a panel engagement element cooperating with a slide engagement element of the movable panel, wherein a movement of the slide is capable of generating a tilting and/or sliding movement of the panel. | {
"pile_set_name": "USPTO Backgrounds"
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A touch sensor has been known as an interface for a user to input information to a display device. Arrangement of a touch sensor so as to overlap with a screen of a display device allows a user to operate input buttons, icons, and the like displayed on a screen, by which information can be readily input to a display device. For example, Japanese patent application publications No. 2015-50245 and No. 2011-23558 disclose an electronic apparatus in which a touch sensor is mounted over an organic EL (Electroluminescence) display device. | {
"pile_set_name": "USPTO Backgrounds"
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When an insufficient amount of refrigerant is circulated through the refrigerant compressor of the refrigeration system of an air conditioner due to, for example, leakage of the refrigerant from the system, not only the refrigeration system will be starved but, the refrigerant temperature in the cooling cycle with respect to a thermal load rises, and in particular a refrigerant suction and discharged fluid temperature will rise. The insufficient lubrication results from leakage of the lubricant contained in the refrigerant being allowed to leak from the refrigeration system.
The present invention contemplates provision of a device adapted to stop the refrigerant compressor or produce a warning signal in the event the temperature in the refrigerant compressor raises beyond a predetermined critical value due to the lack of refrigerant passed through the compressor. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to futon mattresses filled with down and feathers.
2. Description of Related Art
A futon is a type of mattress popular in Japan. Typically, a futon comprises a thick cotton batting encased in a fabric ticking. The batting comprises non-woven cotton fibers, which are stuffed into the ticking and tufted thereto. The batting has a limited ability to hold together, and the tufting inhibits shifting of the batting within the outer ticking.
In Japan, futons are typically laid upon the floor of a common living area at night for sleeping, and removed and stored during the day, so that one area of a dwelling can function as a sleeping area at night, and a living area during the day. Due to Japan's high population density, most dwellings are much smaller than their American counterparts, and futons increase the useable space in the dwelling.
Recently, futons have become popular in the United States. Initially, futons were most popular with urban dwellers and college students. Many American cities also experience high population density with resulting small dwelling spaces. College dormitories are notorious for their limited space. Accordingly, futons provide a means by which urban dwellers and college students can extend their useable living space. Also, futons tend to be rather inexpensive compared to more traditional American forms of bedding.
While in Japan futons are typically placed directly upon the floor, in the United States, futons are typically placed upon a futon frame. Many styles of frames exist, but a fairly standard feature is the ability to convert from a bed into a couch. In the bed position, the frame comprises a platform having an upper surface comprising a series of parallel slats which are elevated above the floor surface. In the couch position, a portion of the futon frame rotates into a somewhat vertical orientation form a back of the couch. The remainder of the frame retains its essentially horizontal orientation to form a seat of the couch. Futon frames come in many variations to serve a variety of needs.
The cotton batting in a standard futon tends to mat down over time. Thus, depressions are formed in the mattress in areas receiving constant concentrations of weight. For instance, the area upon which a user's hips rest while sleeping, and the area upon which the user normally sits both become matted down. With some styles of futon frames, this problem is exacerbated as the sitting area and the hip location during sleeping are the same. Proper maintenance of a futon entails frequent rearranging of the futon upon the frame to minimize localized matting down of the cotton batting. This procedure is both relatively ineffective at limiting the matting down process, and difficult due to the great weight of the futon mattress. Typically, a large futon mattress suitable for use by two people at one time weighs in excess of fifty pounds. Higher weights are not uncommon. Some futons incorporate a foam core, surrounded by cotton batting, which alleviates the above problems somewhat. | {
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Conventional cases are generally made of wood and combined together with nails, and speed of their manufacture is slow, to a resultant high cost. Cases made of plastic shown in FIG. 4 are made of a long plastic plate cut with V-shaped grooves B, then folded up and glued together with connectors C, forming a complete case. Though this plastic case can be made quicker than wooden cases, and its material is easy to get, it needs adhesive process, which slows down manufacturing speed. Even if it is made by ejecting process, it still takes time to let it cool down for taking it off a mold, as it has a thick wall, not a hollow one, having heavy weight. | {
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A need for energy has placed an emphasis on obtaining energy from renewable sources. Organic photovoltaic devices may offer a practical path to achieve low-cost, renewable energy by converting light to electricity. One component of an organic photovoltaic device may be a p-type material. The p-type material may be a donor-acceptor polymer that includes a plurality of alternating electron-rich (donor) units and electron-deficient (acceptor) units. A solar cell may be formed by appropriately coupling the donor-acceptor polymer with an n-type material, an anode, and a cathode. For example, the donor-acceptor polymer may be coupled with the n-type material as a bulk heterojunction between the anode and the cathode.
A donor-acceptor polymer may have a high degree of conjugation and may have a high degree of crystallinity to enable charge separation and transport. The donor-acceptor polymer may also have one or more alkyl side chains covalently coupled to a backbone of the donor-acceptor polymer to improve solubility of the donor-acceptor polymer and enable solution processing into large area films. The backbone of the polymer may include one or more fused ring structures to promote planarity of the donor-acceptor polymer. | {
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Current devices that monitor the relative alignment of the two eyes with each other use eye-tracking methods to determine the accuracy of fixation of each eye separately on a specified fixation point. The relative stability of the alignment of the two eyes with each other is thereby inferred by comparison of the accuracy of fixation of the two eyes separately.
Numerous eye-tracking devices and methods are known to the art. Specifically useful, especially with children, are those methods that determine the gaze point of an eye from a distance, without requiring apparatus worn on the head of the subject. Many such methods infer the direction of gaze from the position of the pupil in a video image as the eye looks in one direction or the other. Such pupil-tracking methods require the head to be still and require the obtaining of multiple calibration points within the visual scene, involving the recording of pupil positions versus respective test points in the visual scene, for accurate estimation of the gaze point of the eye during subsequent eye tracking and recording.
Other eye-tracking devices and methods use not only the position of the pupil in a video image, but also use the position of the corneal light reflection of a small source of light. The image of the corneal light reflection is a virtual image approximately 1 mm posterior to the pupil in the human eye, so that both the pupil and the corneal light reflection can be imaged sharply by the recording camera. When the eye moves in one direction, both the pupil and the corneal light reflection move in that same direction but at different speeds, with the corneal light reflection moving only about half as fast as the movement of the pupil. Therefore the position of the corneal light reflection, with respect to the position of the pupil, with appropriate calibration, yields an estimate of the gaze point, in relation to the positions of the camera and the small source of light, which is reasonably independent of head position. If the small source of light is placed conjugate to the aperture of the camera via a beam splitter, the video image of the eye has a bright pupil, because the eye's optics return the reflected light from the retina back towards the source, where it enters the camera aperture, yielding the bright pupil in the image. If the small source of light is placed eccentric enough to the camera aperture, the pupil remains dark, although the corneal light reflection of the source of light is still present, somewhat eccentric. Both bright-pupil and dark-pupil methods have been used successfully for eye tracking.
The primary remaining disadvantage of eye tracking devices and methods that use images of the pupil, and/or images of lights reflected by the cornea, to estimate the gaze point, is the necessity to calibrate the device for each individual eye, given the variability of eye size, corneal curvature, and pupil positions in the population.
Other devices and methods exist for detecting when an eye is looking in a given direction. The fovea is that part of the retina where vision is most acute, and this is the part of the retina that is aimed at the object of regard during fixation. The nerve fibers in the retina radiate out from the fovea like the spokes of a bicycle wheel. These nerve fibers have a small amount of “form” birefringence that changes the nature of polarized light that passes through them, with the type and amount of polarization change varying with the angular direction of the nerve fibers. Polarized incident light that is reflected from the back of the eye passes through these nerve fibers twice, and the resulting change in the polarization of the double-pass light can be detected by sensors near the source of the polarized light. By scanning a spot of light about in a specified manner on the retina, a spatial birefringence-produced polarization signature can be obtained of that patch of nerve fibers encountered by the scan. Specifically, if a circular scan of the spot of light is centered exactly on the fovea, polarization changes can be detected in the double-pass light that occur at exactly twice the frequency of the scan, as described in U.S. Pat. No. 6,027,216. A high level of this double-frequency signal thus detects eye fixation on a spot in the center of the circular scan of light. This method of detecting eye fixation in a given direction has been termed “retinal birefringence scanning.”
Detection of eye fixation via retinal birefringence scanning does not require calibration in specific directions of gaze as do the video-based pupil-tracking methods, because retinal birefringence scanning detects the anatomic fovea directly by sensing centration of the circular scan on the radial nerve fibers emanating from the fovea. But using retinal birefringence scanning for eye tracking, rather than simply for eye fixation detection, becomes complicated because the polarization signatures of many areas of the nerve fibers away from the fovea are neither unique nor of high amplitude.
There are still other methods for tracking the positions of the eyes. These include tracking the positions of only the corneal light reflections from the eyes, tracking the positions of the corneal/scleral junctions of the eyes, tracking the positions of anatomic features of the eyes using optical coherence tomography, and tracking the positions of the eyes using scleral search coil recordings.
Recently it has been discovered that eyes with amblyopia (decreased vision in an eye caused by misalignment or defocus in early life), typically have a small amount of misalignment with the other eye when viewing a small fixation target. U.S. Pat. No. 7,959,292 B2 describes a binocular retinal birefringence scanning device which, by detecting such small amounts of misalignment on a fixation target, can identify children (or adults) with amblyopia. Even more recently it has been discovered that eyes with amblyopia do not fixate steadily on a small target, either under monocular or binocular conditions. [See González E G, et al. Invest Ophthalmol Vis Sci. 2012; 53(9):5386-94, and Subramanian V, Jost R M, Birch E E. Invest Ophthalmol Vis Sci. 2013; 54(3):1998-2003.] It therefore appears that there is not a constant misalignment of the amblyopic eye, but rather a varying misalignment.
The eyes normally move tightly together in various directions of gaze, with this “conjugacy” of the movements of the two eyes regulated and maintained by the normal binocular vision system. When the eyes have roughly equal vision and are working perfectly well together (“fusing” peripherally and centrally), the brain continually senses if and when the eyes begin to become misaligned, via impending double vision, and makes fine adjustments to the signals to the eye muscles to keep the eyes aligned. Over time, with repetition of these signals occurring in various directions of gaze, “vergence adaptation” causes a “map” to be established in the brain, a map of how much each of the 12 eye muscles should be stimulated to maintain alignment of the two eyes with each other in each direction of gaze and at each distance from the individual. The result is that the eyes move tightly together when binocular vision is normal, both remaining fixated tightly on the object of regard. Even when one eye is covered, its movement behind the cover is quite conjugate with the movement of the fixing eye—again, when binocular vision is normal.
This normal conjugacy of the movements of the two eyes with one another has been documented for decades by binocular eye tracking when subjects are instructed to look quickly from one specific point to another (such a quick eye movement is called a “saccade”). To be sure, horizontal binocular saccades have been shown to be disconjugate when one eye is amblyopic [Maxwell G F, Lemij H G, Collewijn. Conjugacy of saccades in deep amblyopia. Invest Ophthalmol Vis Sci. 1995; 36:2514-2522], and also horizontally disconjugate when strabismus is present (misalignment of the two eyes) [Kapoula Z, Bucci M P, Eggert T, Garraud L. Impairment of the binocular coordination of saccades in strabismus. Vision Res. 1997; 37:2757-2766]. Furthermore, in the presence of strabismus, saccades have been shown to be disconjugate in direction as well as in amplitude [Walton W W G, Ono S, Mustari M. Vertical and oblique saccade disconjugacy in strabismus. Invest Ophthalmol Vis Sci. 2014; 55:275-290].
Thus deficits of binocular function (strabismus, amblyopia, monocular blindness, etc.) cause disconjugacy of eye movements and disconjugacy of the moment-to-moment positions of the two eyes with respect to one another. Indeed, we have experimentally confirmed that, in the presence of deficits of binocular function (occurring with strabismus, amblyopia, monocular blindness, traumatic brain injury, inebriation, fatigue, etc.), the positions of the two eyes vary with respect to one another during ordinary viewing. In the reverse, detecting variability of the alignment of the two eyes with each other (detecting “disconjugate” alignment over time) can serve as a means to screen for deficits of binocular function. The eye-tracking or fixation-detecting methods described above may be used for such a purpose, but each such method is subject to significant limitations, especially with infants and young children. For example, the pupil-tracking methods and corneal light reflex/pupil-tracking methods all require gaze calibration for proper functioning, with such calibration difficult if not impossible with infants and young children. The binocular retinal birefringence scanning method only detects the presence or absence of fixation of each eye separately; it does not easily detect the amount of misalignment.
Again, to date, devices that monitor the relative alignment of the two eyes with each other use eye-tracking methods to determine the accuracy of fixation of each eye separately on a specified fixation point. The relative stability of the alignment of the two eyes with each other has thereby been inferred by comparison of the accuracy of fixation of the two eyes separately. In one instance the relative horizontal positions of one eye with respect to the other have been calculated from binocular recordings during a fixation task [Raveendran R N, Babu R J, Hess R F, Bobier W R. Transient improvements in fixational stability in strabismic amblyopes following bifoveal fixation and reduced interocular suppression. Ophthalmic Physiol Opt 2014. doi: 10.1111/opo.12119]. In this case, however, this “relative position” technique was to determine how long a bifoveal fixation condition persisted after an initial 10 seconds of bifoveal fixation. The technique used a specific fixation target and was not used for a measurement of the overall variability of the conjugacy of the two eye's positions over time. Likewise, it was not used for the identification of deficits of binocular function.
Note that all of the methods discussed above have required the subject to gaze at, or follow, a small fixation target, a task that is not reliably performed by infants or small children, who comprise the primary population that needs to be screened for deficits of binocular function. Detecting these deficits early in life enables more timely and more effective therapy for lifelong improvement. A method and device are therefore needed to detect variability in the moment-to-moment alignment of the two eyes with each other, to thereby detect deficits of binocular function, without requiring specified gaze on small fixation targets. | {
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1. Field of the Invention
The present invention relates to Venetian blinds and, more specifically, to a lift cord concealable Venetian blind lift control mechanism for use in a Venetian blind for lifting control that keeps the lift cords from sight and from reach of children.
2. Description of the Related Art
A regular Venetian blind is generally comprised of a top rail, a bottom rail, a plurality of slats arranged in parallel between the top rail and the bottom rail, a lift control mechanism for controlling lifting and positioning of the bottom rail to adjust the extending area of the Venetian blind, and a tilting control mechanism for controlling the tiling angle of the slats to regulate the light. The lift control mechanism comprises a lift cord suspended from the top rail at one side for operation by hand to control the elevation of the bottom rail. Because the lift cord is exposed to the outside, it destroys the sense of beauty of the Venetian blind. Further, because a child can easily reach the exposed lift cord, an accident may occur when a child pulling the lift cord for fun.
U.S. Pat. No. 6,024,154 discloses a Venetian blind lift control mechanism, which keeps the lift cords from sight. It is to be noted that the marked numbers described hereunder are quoted directly from U.S. Pat. No. 6,024,154. According to this design, the Venetian blind lift control mechanism comprises a T-shaped retaining member 51 mounted inside the bottom rail 22 on the middle, two lift cord take-up members 32 respectively pivoted to the T-shaped retaining member 51 at two sides and adapted to wind up the lift cords 41 of the Venetian blind, and two spring means 33 adapted to provide a torsional force to the lift cord take-up members 32 respectively. The T-shaped retaining member 51 has a rack 512, which is forced by springs 513 into engagement with engagement means 322 of the lift cord take-up members 32 to stop the lift cord take-up members 32 from rotary motion, keeping the bottom rail 22 at the desired height. When the user pressed the T-shaped retaining member 51, the lift cord take-up members 32 are released for free rotation. At this time, the user can lift the bottom rail 22 for enabling the torsional force of the spring means 33 to force the lift cord take-up members 32 to wind up the lift cords 41, or pull the bottom rail 22 downward against the torsional force of the spring means 33, so as to adjust the bottom rail 22 to the desired height. This Venetian blind lift control mechanism is complicated, resulting in high manufacturing cost and complicated installation procedure. Further, when adjusting the elevation of the bottom rail, the user has to press the T-shaped retaining member with one hand and move the bottom rail with the other hand.
The present invention has been accomplished to provide a lift cord concealable Venetian blind lift control mechanism, which eliminates the aforesaid drawbacks. It is the main object of the present invention to provide a lift cord concealable Venetian blind lift control mechanism, which keeps the lift cords of the Venetian blind from sight and out of reach of children. It is another object of the present invention to provide a lift cord concealable Venetian blind lift control mechanism, which is easy to operation. It is still another object of the present invention to provide a lift cord concealable Venetian blind lift control mechanism, which is simple and inexpensive to manufacture. To achieve these objects of the present invention, the lift cord concealable Venetian blind lift control mechanism is installed in a Venetian blind, which comprises a top rail, a bottom rail, a plurality of slats arranged in parallel between the top rail and the bottom rail, and two lift cords vertically inserted through the slats and arranged in parallel. The lift cord concealable Venetian blind lift control mechanism comprises a base installed in one of the top and bottom rails of the Venetian blind, the base comprising two screw rods axially horizontally aligned in a line between the lift cords, an axle hole axially extended through the screw rods; a revolving rod inserted through the axle hole of the base for free rotation relative to the base, the revolving rod having two distal ends respectively extended out of the screw rods; a spring member mounted in the base and adapted to impart a torsional force to the revolving rod; and two bobbins respectively threaded onto the screw rods and coupled to the ends of the revolving rod for synchronous rotation with said revolving rod and for axial movement relative to the screw rods to wind up/let off the lift cords upon forward/backward rotation of the revolving rod. | {
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Various bone fixation apparatuses have been disclosed in the art, such as those described in Korean Patent Laid-open Publication No. 2000-48562 and U.S. Pat. No. 6,280,442.
As shown in FIG. 1, the bone fixation apparatus described in Korean Patent Laid-open Publication No. 2000-48562 includes a bone screw 10, a shrinkage collet 14, a receiver member 18, and a set screw 20. The bone screw 10 has a spherical head 12. The shrinkage collet 14 functions to support the head 12 of the bone screw 10. The receiver member 18 has a center bore for delimiting a tapered recess 16 in which the shrinkage collet 14 is accommodated and a U-shaped channel that communicates with the recess 16 and through which a support bar R extends. The setscrew 20 is threadedly coupled to the receiver member 18 to downwardly bias the support bar R.
The head 12 of the bone screw 10 is defined with a tool-engaging groove 22 in which a tool can be engaged. The tool engaging groove 22 is defined on a flat upper end surface 24 of the head 12, in which the upper end surface 24 is formed by truncating the head 12. A portion of the receiver member 18 which defines the U-shaped channel is formed with internal threads 26 so that the setscrew 20 can be threadedly coupled to the internal threads 26. A lower surface of the shrinkage collet 14 is formed to have a contoured depression 28 in which the head 12 is partially accommodated. In the contoured depression 28, a lower part of the shrinkage collet 14 is formed with a plurality of slots, so that a desired pressing force is applied to the head 12 of the bone screw 10.
If the setscrew 20 is tightened, the support bar R compresses the shrinkage collet 14, and the shrinkage collet 14 is squeezed within the tapered recess 16 of the receiver member 18 in such a way as to fixedly hold the bone screw 10 at a vertical or inclined position.
Meanwhile, as shown in FIG. 2, in the bone fixation apparatus described in U.S. Pat. No. 6,280,442, a series of ridges 34 are formed on a head 32 of a bone screw 30, a retainer ring 38 is fitted adjacent to a lower end of a receiver member 36 so that the head 32 can be retained by the retainer ring 38. A cap member 40 is placed on an upper part of the head 32. Above the cap member 40, a support bar R is inserted through a U-shaped channel defined in the receiver member 36 and then biased downward by a compression member 42.
In the receiver member 36, a lower part in which the cap member 40 is inserted is formed to have an inner diameter greater than that of the upper part into which the compression member 42 is threadedly coupled. Due to this fact, even in the case that the compression member 42 is unscrewed and the support bar R is removed, the cap member 40 is prevented from being released in an upward direction. When assembling the bone fixation apparatus, after the cap member 40 and the head 32 of the bone screw 30 are sequentially inserted through the lower end of the receiver member 36, the retainer ring 38 is placed around and moved upward on the bone screw 30 and then fitted into an inward annular groove defined adjacent to the lower end of the receiver member 36.
The internal threads of the receiver member 36 may be formed in a manner such that the cap member 40 is also threadedly coupled to the internal threads to be prevented from being released from the receiver member 36.
However, in the former bone fixation apparatus as described in Korean Patent Laid-open Publication No. 2000-48562, the head 12 supported in the tapered recess 16 is likely to be moved by an external factor because the supporting force is insufficient. Consequently, the head 12 cannot be reliably maintained in an initially supported state.
The latter type bone fixation apparatus as described in U.S. Pat. No. 6,280,442, while coping to some extent the problem caused in Korean Patent Laid-open Publication No. 2000-48562, suffers from defects in that it is difficult to fit the retainer ring 38 in place, and the supporting force of the bone screw is still insufficient.
When the head of the bone screw is supported by the cap member threadedly coupled to the receiver member, it is not easy to screw the cap member adjacent to the lower end of the receiver member. Further, because the biasing force of the compression member cannot be transferred to the head, assemblability is deteriorated and the supporting force of the bone screw is downgraded. | {
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During a concrete pouring process, a material that includes aggregates, cement, and water is poured into an area that may be bounded by forms to contain the concrete material. As concrete is delivered into the pour area, a plurality of laborers, often called “puddlers,” using tools such as rakes, come-alongs, and/or shovels, approximate a uniform distribution of the concrete material to the desired elevation. Still other laborers, commonly equipped with a piece of lumber or other straight member referred to as a “strike-off,” move the strike-off across the concrete material. The process of manually striking-off the concrete material consolidates the material and forces the larger aggregate below the finished elevation. It also shapes the surfaces of the concrete to the desired slope or “grade.” The flatness of the finished surface is highly dependant on the skill of the personnel handling the strike-offs. Additionally, manually striking-off the concrete material is very labor intensive and requires a great deal of skill and experience to ensure a flat and properly inclined finished surface.
The advent of the portable vibratory screed greatly reduced the labor associated with leveling of the concrete material. Portable vibratory screeds commonly include a vibration-inducing mechanism attached to a board or blade and one or more handles that extends from the blade. The vibration mechanism typically comprises an “exciter” formed from one or more eccentric weights driven by a motor. Operation of the vibration mechanism consolidates the concrete material such that, as the blade is moved across the wet concrete, the vibrating blade forces the larger aggregate below the surface of the material and works a highly cementatious material with smaller aggregates, often called “cream,” to the finish surface of the material. Operator manipulation of the handle, as well as the rigidity of the blade, directly affects the flatness and inclination of the finished surface of the material. Accordingly, an operator's ability to control the pitch or tilt of the blade as well as the speed and direction of travel of the blade determines the flatness of the finished material.
To reduce the transmission of vibrations to the operator's hands from the vibration mechanism, an isolation mechanism, such as a rubber bushing, is commonly disposed between the end of the handle and the blade. However, the isolation mechanism provides an undesirable response to handle movement during operation because the isolation mechanism distorts upon handle movement so that only a portion of the effect of the handle's motion is translated to the blade. Accordingly, the isolation mechanism detrimentally affects the operator's ability to control the position of the blade.
The elevation of the finished material is also commonly determined by the operator's visual inspection of the finish elevation in relation to the elevation references such as the forms. Although portable vibratory screed assemblies are known which include various inclination indication systems, such systems are commonly directed to targeted users. Many inclination and elevation systems include laser systems. However, many such systems fail to address the positioning of the handle, and thereby the pitch of the blade, relative to the bottom surface of the blade. As such, such laser elevation systems are only somewhat successful at properly indicating to the operator the direction the handle should be moved to acquire an elevation and/or pitch that is consistent with the desired elevation. Additionally, the laser elevation and inclination systems are costly to integrate into a screed. From a manufacturing perspective, these costs are commonly deferred to the customer as well as the costs associated with the service and maintenance requirements of such systems.
Others, such as the system disclosed in U.S. Pat. No. 4,752,156, have relatively inexpensive inclinators, such as a site level, for indicating the orientation of the screed plate. A site level, often known as a bubble vial, is formed from a glass tube having a bubble encased in a liquid. The bubble is centered in the vial when the vial is horizontal and rises toward one end or the other if the vial is inclined relative to the movement. However, as discussed in U.S. Pat. No. 6,758,631 the '631 patent, such indicators have been less than successful at indicating the inclination of the blade of the screed during operation of an exciter assembly. That is, vibrations generated by operation of the exciter assembly propagate to the bubble vial and obliterate the bubble of the site level, rendering it useless. The '631 patent concludes that bubble vials or site levels are unacceptable for screed inclination indication during screeding. | {
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1. Field
The field of the invention is devices for leveling the bodies of vehicle drawn trailers when parked.
2. Prior Art
A recurrent problem in the use of vehicle drawn trailers is parking upon uneven ground, wherein the trailer tends to repose into a tilted position if allowed to rest upon its wheels. Often, standard axle jacks do not easily lift the trailer sufficiently to level the trailer condition. Even then, chocks or the like must be placed to support both wheel ends of the axles for parking. Several auxiliary devices have been proposed wherein a jack engageable member is secured to the trailer frame to extend laterally for purchase of jacks beside, rather than beneath, the trailer body. In U.S. Pat. No. 3,802,664, a crossbar is secured to side members of the trailer frame to extend beyond the outside trailer walls to provide a vertical jacking plate. The latter is engaged by a conventional automobile bumper jack. One serious shortcoming is that crossbar can only be secured below the frame members so that it projects downwardly, which is particularly vulnerable to dragging against the ground of rough roads and driveways. With this device, the bumper jack's grasp upon the plates is tenuous at best, with no positive lock between jack and plate.
Clearly, a need remains for a trailer attached apparatus for jacking the trailer to a laterally and longitudinally level position when parked on sloping and uneven ground. | {
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1. Field of the Invention
This invention relates to optical communication systems. More particularly, this invention relates to a method and apparatus for looping-back an optical signal used in optical communications.
2. The Prior Art
Continuity of optical fiber transmission lines is often tested using an Optical Time Domain Reflectometer (OTDR), which sends an optical signal into an optical fiber and then senses any reflections off of discontinuities, such as breaks, returning on the optical fiber to the OTDR. Use of an OTDR interrupts the normal transmission of data and does not allow for diagnostic analysis of other aspects of an optical network during the OTDR tests. Furthermore, OTDRs are expensive pieces of test equipment. Therefore, cost limitations prevent the simultaneous use of OTDRs on many different transmission lines of an optical network. Furthermore, OTDR detection of signal discontinuities may be difficult due to normal attenuation of the OTDR signal in the case of long transmission lines. OTDR's also have the disadvantage of not being able to perform several important functions, including: testing transmission line integrity; performing round trip performance analysis; injecting and detecting errors; and, testing higher communications layers.
Loop-back, in which a signal is sent down one optical fiber and returned on another optical fiber, is a less costly method of detecting discontinuities than using OTDR's. However, conventional loop-back systems require the entire transmission line be dedicated to the loop-back process during a discontinuity test or a performance test. Furthermore, loop-back tests are limited in range due to the fact that the test beam may be significantly attenuated due to the added optical path length introduced in the loop-back process.
Nowhere does the prior art disclose a method or apparatus for employing loop-back in a discontinuity test that allows continued use of the transmission line for the transmission of data and that uses normal data for the discontinuity test and that regenerates the test beam. | {
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1. Field of the Invention
The present invention is in the area of lubrication of rolling/sliding surfaces that may be required to operate over a large range of kinematic, stress and environmental conditions. Lubrication is conventionally supplied by liquid, solid, and sometimes gaseous materials which provide some kind of low shear strength film between the moving surfaces. The most reliable lubricating films are those generated by hydrodynamic (HD) or elastohydrodynamic (EHD) mechanisms which separate the surfaces by a pumping action due to the convergent nature of contact geometries in motion which generates sufficient pressure to cause a separation of the surfaces. This is done by fluids or lubricants having certain viscous properties. The oils are supplied to the contacting surfaces as a liquid in quantities generally sufficient for lubrication and cooling. Cooling is necessary because of temperature limitations which are almost always related to the oil's viscosity for lubrication or the thermal breakdown of the oil itself. To maintain proper cooling along with lubrication, oils are usually recirculated through a lubrication system with pumps, coolers, sumps, delivery lines and filters. One oil is used with selected viscous properties to cover a specific, but limited, range of temperatures.
This invention provides the processes and devices to lubricate surfaces over a broad temperature range with a small quantity of fluid that can be supplied with a simple system. The invention consists of the lubrication of surfaces with condensed vapors (vapor/condensation, or V/C lubrication) or with vapors that react with the surfaces (vapor/deposition, or V/D lubrication). The condensed vapors are sufficient in thickness to allow EHD film generation and even HD film generation. The amount of lubricant necessary to generate EHD lubricant films is very small, being only a "whisper" of condensate. A companion patent application Ser. No. 08/243,112, filed May 16, 1994, discloses the method for broad temperature range vapor lubrication. Vapors that react with the surfaces (see U.S. Pat. No. 3,978,908 September 1976 E. E. Klaus et al.) are used here as boundary films to supplement V/C lubrication. The preferred mechanism of lubrication is EHD where the surfaces are completely separated with an oil film so that the longest possible life of the surface can be achieved. The boundary film mechanism is called upon when the EHD mechanisms can no longer be maintained.
The invention is most practical with fluids that can be vaporized without leaving breakdown deposits or having the potential for fire. Presently, the most useful fluids are the perfluoropolyalkyethers (PFPE) which do not have a flash or fire point and can be vaporized and condensed without solid breakdown products. Another advantage of PFPE's is their availability over a large range of molecular weights or viscosities. This allows a new form of lubrication which is called variable property (VP) lubrication (see companion patent application Ser. No. 08/243,112). VP lubrication provides a condensate film on the surfaces which increases in molecular weight, or viscosity, with temperature so that HD or EHD lubrication is sustained to an extended temperature level. Chemical additives which are normally insoluble in PFPE's can be supplied as vapors to provide boundary lubrication. The introduction of the additive as a vapor circumvents the solubility limit problem with PFPE's.
2. Description of Prior Art
Most mechanical components are lubricated with systems which:
provide pressurized jets of oil; PA1 drip feed oil; PA1 provide an air-oil mist; PA1 provide oil from oil wicks; or PA1 provide oil from an oil sump into which the components dip as they rotate.
Prior art of this invention is illustrated by example with a gas turbine engine lubrication system, as shown in FIG. 1. A lubrication system of some 30 qts of oil is used to lubricate and cool mainshaft bearings and the accessory gearboxes. An extensive network of high pressure oil feed lines are used with oil jets at the main bearing sites to introduce lubrication and cooling flows. The oil is scavenged and returned to a tank, oil cooler and filter for recirculation.
The technical limits of performance in a gas turbine engine, as well as other engine types, is the temperature limit of the lubricating oil. Extensive efforts are made to prevent oil coking, especially in the feed lines which can become clogged. To prevent coking the oil is cooled and not allowed to become stagnant, especially on certain metals which can catalytically accelerate the coking process. Conventional lubricants are carefully formulated synthetic ester base oils which have good thermal and oxidatively stability. These oils generally fall under the MIL-L-23699 specification which have strict limits on viscosity, pour point, flash temperature, load carrying capacity and coking attributes. The selection of these specifications are to assure that the oil is not too viscous (or solid) for low temperature starting (-40.degree. F.), but yet viscous enough for high temperature running (bulk oil temperature of 450.degree. F.). With current basestock and additive technology, there is little room for improvement with ester base oils. Alternative basestocks are PFPE's and polyphenyl ether (PPE) lubricants. Both of these have inferior boundary lubricating attributes and the latter oil does not have good low temperature properties. To satisfy high temperature operation for military engines high temperature solid lubricants have been investigated, but their performance is not reliable and their life is too limited to be practical. The primary limitations of conventional liquid lubricating systems is their limited temperature range and the complex hardware that is necessary to obtain maximum use out of the performance limits. | {
"pile_set_name": "USPTO Backgrounds"
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A major complication of cancer chemotherapy and of antiviral chemotherapy is damage to bone marrow cells or suppression of their function. Specifically, chemotherapy damages or destroys hematopoietic precursor cells, primarily found in the bone marrow and spleen, impairing the production of new blood cells (granulocytes, lymphocytes, erythrocytes, monocytes, platelets, etc.). Treatment of cancer patients with 5-fluorouracil, for example, reduces the number of leukocytes (lymphocytes and/or granulocytes), and can result in enhanced susceptibility of the patients to infection. Many cancer patients die of infection or other consequences of hematopoietic failure subsequent to chemotherapy. Chemotherapeutic agents can also result in subnormal formation of platelets which produces a propensity toward hemorrhage. Inhibition of erythrocyte production can result in anemia. The risk of damage to the hematopoietic system or other important tissues can prevent utilization of doses of chemotherapy agents high enough to provide good antitumor or antiviral efficacy.
Many antineoplastic or antiviral chemotherapy agents act by inhibiting nucleotide biosynthesis, metabolism, or function, or are in fact nucleoside analogs that substitute for the normal nucleosides in nucleic acids, producing defective RNA or DNA.
5-Fluorouracil is a clinically important cytoreductive antineoplastic chemotherapy agent that acts in part through incorporation into RNA, producing defective RNA; inhibition of thymidylate synthetase by fluorodeoxyuridine monophosphate may also contribute to the cytotoxicity of 5-FU. The clinical utility of 5-FU is limited by its toxicity (especially to bone marrow). Specifically, its clinical utility is limited by a low therapeutic ratio (the ratio of toxic dose to effective dose; a high therapeutic ratio implies that a drug has efficacy with little toxicity).
5-FU and many other chemotherapy agents also affect other tissues, especially gastrointestinal mucosa, producing mucositis, diarrhea and ulceration. Stomatitis (ulceration of mucosa in the mouth), is particularly troublesome to patients, making eating and swallowing painful.
D. S. Martin et al. (Cancer Res. 42:3964–70 [1982]) reported that a toxic dose of 5-FU (with strong anti-tumor activity) could be safely administered to mice if followed by administration of a high dose of uridine beginning several hours later. This “rescue” strategy has been shown to increase the therapeutic index of 5-FU in animal tumor models, allowing administration of the high, toxic doses of 5-FU that are necessary for causing tumor regresssion or preventing tumor growth while preferentially protecting normal tissues (especially important is bone marrow) by subsequent administration of uridine (D. S. Martin et al., Cancer Res. 43:4653–61 [1983]).
Clinical trials involving the administration of uridine have been complicated due to the biological properties of uridine itself. Uridine is poorly absorbed after oral administration; diarrhea is dose limiting in humans (van Groeningen et al., Proceedings of the AACR 28:195 [1987]). Consequently, parenteral administration of uridine is necessary for clinically significant reversal of 5-FU toxicity, which requires use of a central venous catheter, since phlebitis has been a problem in early clinical trials when uridine was administered via a small intravenous catheter (van Groeningen et al. Cancer Treat Rep. 70:745–50 [1986]). Prolonged infusion via central venous catheters requires hospitalization of the patients. Further, there is considerable discomfort and inconvenience to the patients.
Orally-active prodrugs of 5FU have been developed which are enzymatically or spontaneously converted to 5FU, generally after absorption from the intestine into the bloodstream. This permits self-administration by patients, without the discomfort of intravenous administration. Moreover, in some chemotherapy regimens, sustained exposure, e.g. a constant intravenous infusion for several days or weeks, of tumors to 5FU is attempted. Oral administration of 5FU prodrugs can in principle provide such sustained availability of 5FU to tumors.
5-Fluoro-1-(tetrahydro-2-furfuryl)uracil (FT) is an orally active prodrug of 5-fluorouracil. It is enzymatically converted to 5-fluorouracil primarily in the liver. The liver, however, has relatively high levels of the enzyme dihydropyrimidine dehydrogenase, which degrades 5FU, producing metabolites which are not useful in cancer chemotherapy and which furthermore contribute to 5-FU toxicity.
The cytotoxicity of 5FU, the active metabolite of FT, is believed to be a result of its incorporation into nucleotide pools, where certain anabolites exert toxic effects, e.g. 5-fluorodeoxyuridine monophosphate inhibits thymidylate synthetase, thus depriving cells of thymidine for DNA synthesis, and 5-fluorouridine triphosphate incorporation into RNA impairs its normal functions in translation of genetic information.
In order to inhibit the catabolism of 5FU derived from FT, other compounds have been administered with the FT. In particular, the pyrimidine uracil inhibits the catabolism of 5FU without inhibiting its cytotoxicity. The most widely used clinical formulation of FT contains uracil in a 1:4 molar ratio. This permits a significant reduction in the dose of FT required to achieve a therapeutic effect. Other pyridimines, including uridine, thymidine, thymine, and cytosine are either less effective than uracil or no better in potentiating the antitumor efficacy of FT without unacceptably potentiating toxicity. Potent synthetic inhibitors of dihydropyrimidine dehydrogenase (DHPDHase) have also been utilized with FT or 5FU. 5-chloro-2,6-dihydroxypyridine (CDHP) is more potent than uracil as an inhibitor of DHPDHase. However, this compound also enhances the toxicity of 5FU, so that, in its intended clinical implementation, a third component, oxonic acid, is co-administered to reduce the intestinal toxicity.
Several investigators have administered pyrimidines with 5FU attempting to improve the therapeutic index of this antineoplastic agent. In vivo, uridine and thymidine when administered at the same time as 5FU increased both the antitumor efficacy of 5FU and its toxicity, so that there was no net increase in therapeutic index (Hartman and Bollag, Med. Oncol. & Tumor Pharmacother., 3:111–118 [1986]). Burchenal et al. (Cancer Chemother. Rep., 6:1–5 [1960]) summarized comprehensive studies on interactions of 5FU and 5-fluorodeoxyuridine (FUDR) and pyrimidine compounds. They noted that despite the fact that pyrimidines and pyrimidine nucleosides, at doses which are inactive alone, markedly potentiate the antileukemic effects of small doses of FUDR or FU, it has not been possible with any combination to improve significantly and with any degree of regularity the results which can be obtained with maximum tolerated doses of FU or FUDR alone. Similarly, Jato et al. (J. Pharm Sci., 64:943–945 [1975]), in an investigation of combinations of deoxyuridine with 5FU and FUDR report that any therapeutic benefit of the combination therapy could be duplicated with either 5FU or FUDR at a higher dose. Although deoxyuridine, by inhibiting the catabolism of the fluoropyrimdines permitted administration of lower doses, deoxyuridine there was no improvement in antitumor activity at equitoxic doses of the combination versus FU or FUDR alone.
As in the case of uridine, problems of poor bioavailability after oral administration limit the clinical utility of administration of deoxycytidine, cytidine, and deoxyuridine themselves for modulation of toxicity of chemotherapy agents.
Arabinosyl cytosine (Ara-C) is an important agent in the treatment of leukemia, and is also useful as an immunosuppressant. Bone marrow toxicity (myeloid and erythroid) associated with Ara-C administration can be partially prevented by administration of deoxycytidine (Belyanchikova et al. Bull. Exp. Biol. Med. 91:83–85 [1981]), while the toxicity of Ara-C to lymphocytes is not as strongly attenuated by deoxycytidine. In cell cultures, normal myeloid progenitor cells are protected from Ara-C by deoxycytidine better than are leukemic cells (K. Bhalla et al. Blood 70:568–571 [1987]). Deoxycytidine also attenuates toxicity of 5-aza-2′-deoxycytidine and arabinosyl 5-azacytosine in cell cultures (K. Bhalla et al. Leukemia 1:814–819 [1987]). Prolonged (5 day) infusion of high doses of deoxycytidine via a central venous catheter was proposed as a means for clinical implementation of modulation of Ara-C toxicity with deoxycytidine (K. Bhalla et al. Leukemia 2:709–710 [1988]).
N-phosphonoacetyl-L-aspartic acid (PALA) is an antineoplastic agent that inhibits the enzyme aspartate transcarbamoylase, an enzyme indirectly involved in biosynthesis of pyrimidine nucleotides. Side effects of PALA primarily involve damage to gastrointestinal toxicity and mucositis. Pyrazofurin (a carbon linked pyrimidine analog), 6-azauridine, and 6-azacytidine all interfere with pyrimidine nucleotide synthesis and metabolism.
3′-Azidodeoxythymidine (AZT) is used clinically in patients infected with Human Immunodeficiency Virus (HIV, the infectious agent in AIDS). AZT prolongs the lifespan of patients infected with HIV, but also impairs hematopoiesis, producing leukopenia and anemia. In cell cultures, uridine ameliorates AZT-induced toxicity to granulocyte/macrophage progenitor cells without impairing the antiviral actions of AZT (Sommadossi et al., (1988) Antimicrobial Agents and Chemotherapy, 32:997–1001); thymidine attenuated both toxicity and antiviral activity. In mice, parenteral administration of high doses of uridine provided some amelioration of AZT-induced anemia, but only at uridine doses which increased mortality during the study; a low, non-toxic dose of uridine (500 mg/kg/d) did not reduce AZT-induced hematologic toxicity (A. Falcone, et al. Blood 76:2216–21 [1990]). Sommadossi and el Kouni (U.S. Pat. No. 5,077,280) proposed the administration of uridine by periodic intravenous injection in order to attenuate AZT toxicity. Bhalla et al. (Blood 74:1923–1928 [1989]) reported that deoxycytidine protects normal human bone marrow progenitor cells in vitro against the cytotoxicity of AZT with preservation of antiretroviral activity.
5-Fluoroorotate, an analog of the pyrimidine nucleotide precursor orotic acid, has antiproliferative effects on human cells, but is especially useful for treating infections with malarial parasites, e.g., Plasmodium yoelii or Plasmodium falciparum, which are dependent on de novo pyrimidine biosynthesis. Administration of uridine to mice treated with 5-fluoroorotate attenuated host toxicity due to the latter without impairing its antimalarial activity (ZM Gomez and PK Rathod, Antimicrob. Agents Chemother. 34:1371–1375 (1990).
Dideoxycytidine (ddC) is also useful against retroviral infections including HIV; side effects of ddC include peripheral neuropathy, mouth ulcers, and reduced platelet counts. The toxicity of ddC on human myeloid progenitor cells in culture can be ameliorated by deoxycytidine without thereby impairing the antiretroviral efficacy of ddC (K. Bhalla et al., AIDS 4:427–31 [1990]).
The methods disclosed in the prior art cited above for administering these pyrimidine nucleosides to modify chemotherapy in the clinical setting are neither practical (prolonged infusion of deoxycytidine or uridine via a central venous catheter requires hospitalization, risk of infection, and discomfort to the patient) or satisfactory (orally administered uridine is poorly absorbed; therapeutically adequate doses of oral uridine produce diarrhea).
Commonly owned U.S. patent application Ser. No. 438,493 demonstrates the use of acylated derivatives of cytidine and uridine to increase blood cytidine or uridine levels.
Some acyl derivatives of pyrimidine nucleosides have been synthesized for use as protected intermediates in the synthesis of oligonucleotides or nucleoside analogs, e.g. 5′-O-benzoyluridine, triacetylcytidine, and triacetyluridine. See Sigma Chemical Company 1991 catalog, pages 155, 980, and 981 respectively. | {
"pile_set_name": "USPTO Backgrounds"
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Server and desktop virtualization is dramatically changing the enterprise network by creating many “virtual networks” which connect virtual machines and the physical networks through virtual switches. In this new network paradigm, many new network services requirements are imposed on modern IT network infrastructure. For example, in a virtual network, inter-virtual machine (VM) communication is a blind spot because this traffic never reaches the physical network, making it unprotected by a physical network security appliance. The absence of protection in a virtual network becomes a key security concern in a virtualized data center, especially in a multi-tenant cloud service provider data center environment where it is required to deploy a virtual service that serves as a segmentation firewall for all the managed virtual machines. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to a power management system and more particularly to a power management system for the supply of power to an implantable medical device, such as an implantable hearing prosthesis.
2. Related Art
Implantable medical devices, such as cochlear implants, middle ear implants, FES systems and the like, typically consist of two components, one part being an external component commonly referred to as a processor unit and the other part being an implanted internal component commonly referred to as a stimulator/receiver unit. Traditionally both of these components cooperate together to provide a desirable therapy to the implantee. In the case of implantable hearing prosthesis such as cochlear implants and/or middle ear implants, the external component has consisted of a microphone for detecting sounds, such as speech and environmental sounds, a speech processor that converts the detected sounds and particularly speech into a coded signal, a power source such as a battery and an external antenna/transmitter.
The coded signal output by the speech processor can be transmitted transcutaneously to the implanted stimulator/receiver unit situated within the head of the implantee. The transmission can occur through use of an inductive coupling provided between the external antenna transmitter and an implanted antenna/receiver which forms part of the stimulator/receiver unit. The communication serves to transmit the coded sound signal and to provide power to the implanted stimulator/receiver unit. The external part is generally worn outside the skin and can be positioned behind-the-ear like a traditional BTE hearing aid and contains the components mentioned previously.
The implanted stimulator/receiver unit typically includes the antenna/receiver that receives the coded signal and power from the external processor component, and a stimulator that processes the coded signal and outputs a stimulation signal to an assembly, which applies the stimulation to generate the desired therapy. In the case of a middle ear implant, the assembly may include a mechanical or hydromechanical actuator device that is coupled to the ossicles of the middle ear or directly to the inner ear for applying direct stimulation thereto, producing a hearing sensation corresponding to the originally detected sound. In the case of cochlear implants, the assembly may include an intra cochlear electrode assembly, which applies electrical stimulation directly to the auditory nerve producing a hearing sensation corresponding to the original detected sound. The implanted unit is located under the skin inside the mastoid and contains primarily means to demodulate or decode the signals transferred through the skin to drive an actuator or an electrode array and to convert the power transferred through the skin into an electric supply voltage. In known systems the implanted portion does not contain any independent power source and consequently the transcutaneous link must be in place and therefore the wearer must wear the external component permanently, which impedes the comfort of the wearer.
Due to other particular problems with the external components of existing hearing prosthetic devices, such as the aesthetics associated with wearing a visible external device, the wearer having to remove the device while showering or engaging in water related activities, and the likelihood that the alignment between the external and internal coils will be lost due to movements during sleep or physical activity, there exists a need to provide a system that allows for total freedom with improved simplicity and reliability. Consequently research has been directed to fully implantable hearing prosthetic systems that do not require external components for the operation thereof. This would include providing a medium-to-long term power source such as rechargeable batteries, in the implants to overcome the need for power to be continually transmitted to the implant from an external power source.
However certain challenges appear with providing implanted devices with such implanted power sources. Unlike ceramic capacitors used as present-day short-term energy reservoirs, a rechargeable battery degrades irreversibly during its lifetime. They can only undergo a particular maximum number of recharging cycles before the battery performance diminishes to a level where the battery is essentially unusable. The degradation is due to the decomposition of the electrolyte and due to electrode corrosion. The decomposition of the electrolyte can cause the generation of side products like hydrogen and other gases that tend to build up pressure in the battery enclosure and finally escape through flaws in the enclosure. Corrosion of electrodes leads to a reduction of the active surface area and may ultimately, if the battery continues to be charged and discharged, cause a short circuit inside the battery through metal spikes growing from one electrode to the other. Both effects lead to a reduction of the available battery capacity and ultimately to total failure. In the worst case, the implanted battery may rupture causing a severe threat to the health and well being of the wearer. Furthermore, if rechargeable batteries are discharged before being fully charged or conversely charged before being fully discharged, their overall capacity may be prematurely reduced.
Totally implantable hearing systems require a substantial amount of energy to be stored since the whole signal processing unit and supporting functions have to be supplied for a reasonable period of time. In order to be commercially viable, the required battery life per charge is generally considered as being in the order of a week. On the other hand, the number of recharging cycles of a storage battery is limited. Thus the capacity and ultimate size of an implanted battery must be made as large as possible. However, such application of large batteries causes further challenges, including that they require thick enclosures, that is considered dead space, in order to retain the pressure of evading gases. Large batteries are also prone to the occurrence of internal short circuiting and battery failures are due to their larger surface area. Furthermore, the larger the battery is, the more severe the thermal effect of a battery failure causing accumulative thermal damage to surrounding tissue.
It is desired to overcome, or at lease ameliorate any one or more of the shortcomings of prior arrangements. | {
"pile_set_name": "USPTO Backgrounds"
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In garment bags of the type used in traveling, the clothes are packed in the bag when the bag is in an extended or unfolded vertical hanging position. The clothes are suspended from hangers and the hangers are connected to a trolley within the interior of the bag. To retain the clothes in the position within the bag when it is folded into a suitcase-like configuration, a belt-like strap in the midsection of the bag is fastened around the clothes. This strap is particularly important because the clothes are bent around it and suspended from it when the bag is folded in the suitcase-like configuration. Without the center strap, the clothes would shift and slide into piles in the bottom of the bag when the bag was folded. One disadvantage of the center strap is that it has a tendency to wrinkle the clothes, particularly when it is tightened securely enough to prevent the clothes from slipping and crumpling within the bag.
Wrinkles are also frequently caused at the upper and lower ends of garments carried in the garment bag. Because the clothes are bent double when the bag is folded in its suitcase-like configuration, the tops and bottoms of the garments are at the bottom of the folded bag. The weight of the clothes tends to pull them down into bunches. A typical trolley at the upper end of the bag (which is located at the bottom when the bag is folded into the suitcase-like configuration) usually has the capability to prevent the hangers from falling off, even when the hangers become inverted after the bag is folded into the suitcase-like configuration. However, the shoulders of the garments may slip downward over the inverted hangers and wrinkling may still occur.
At the lower end of the garment bag, the clothes are usually left free. If the garment is a long one, such as a lady's dress or a long coat, the bottom part of it is usually wrinkled because it is bunched in the bottom of the bag. Even when the bag is folded, the bottoms of the long clothes still remain in bunches in the bottom of the bag.
Special hangers are usually used in garment bags in order to conserve space. The neck portion of these garment hangers is generally hinged to fold downward and thereby bring the large triangularly shaped shoulder supporting portion of the hanger up closer to the top of the bag. However, even when such hinged hangers are used, sufficient room still exists for the shoulders to work downward off of the hangers and create wrinkles. Even with such special hinged hangers, no more effective space utilization is obtained because the bottom portion of the bag is still either unoccupied or the clothes which do occupy the bottom portion of the bag are left in bunches.
One recognized approach to achieving further packing capability in a traveling garment bag has been to provide exterior pockets within which small items can be packed. When shoes or other similarly sized items are placed in these exterior pockets, the bag can become somewhat lopsided and awkward to handle in its folded configuration. Items like shoes can be placed in the interior of the bag, but since there is no method of retaining them, they are free to move about and wrinkle and dislodge the clothes. | {
"pile_set_name": "USPTO Backgrounds"
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The present invention relates to a rotating blade for a steam turbine and, more particularly, to a rotating blade for a steam turbine with optimized geometry capable of increased operating speeds.
The steam flow path of a steam turbine is formed by a stationary cylinder and a rotor. A number of stationary vanes are attached to the cylinder in a circumferential array and extend inward into the steam flow path. Similarly, a number of rotating blades are attached to the rotor in a circumferential array and extend outward into the steam flow path. The stationary vanes and rotating blades are arranged in alternating rows so that a row of vanes and the immediately downstream row of blades form a stage. The vanes serve to direct the flow of steam so that it enters the downstream row of blades at the correct angle. The blade airfoils extract energy from the steam, thereby developing the power necessary to drive the rotor and the load attached to it.
The amount of energy extracted by each row of rotating blades depends on the size and shape of the blade airfoils, as well as the quantity of blades in the row. Thus, the shapes of the blade airfoils are an important factor in the thermodynamic performance of the turbine, and determining the geometry of the blade airfoils is an important portion of the turbine design.
As the steam flows through the turbine, its pressure drops through each succeeding stage until the desired discharge pressure is achieved. Thus, the steam properties—that is, temperature, pressure, velocity and moisture content—vary from row to row as the steam expands through the flow path. Consequently, each blade row employs blades having an airfoil shape that is optimized for the steam conditions associated with that row. However, within a given row, the blade airfoil shapes are identical, except in certain turbines in which the airfoil shapes are varied among the blades within the row in order to vary the resonant frequencies.
The blade airfoils extend from a blade root used to secure the blade to the rotor. Conventionally, this is accomplished by imparting a fir tree shape to the root by forming approximately axially extending alternating tangs and grooves along the sides of the blade root. Slots having mating tangs and grooves are formed in the rotor disc. When the blade root is slid into the disc slot, the centrifugal load on the blade, which is very high due to the high rotational speed of the rotor, is distributed along portions of the tangs over which the root and disc are in contact. Because of the high centrifugal loading, the stresses in the blade root and disc slot are very high. It is important, therefore, to minimize the stress concentrations formed by the tangs and grooves and maximize the bearing areas over which the contact forces between the blade root and disc slot occur. This is especially important in the latter rows of a low pressure steam turbine due to the large size and weight of the blades in these rows and the presence of stress corrosion due to moisture in the steam flow.
In addition to the steady centrifugal loading, the blades are also subject to vibration.
The low pressure section rotating turbine blades are typically designed and optimized to cover a given operating speed as required by the different applications. Main operating parameters are annulus area, rotating speed, mass flow capability, and for the last stage blade, condensing pressure.
The difficulty associated with designing a steam turbine blade is exacerbated by the fact that the airfoil shape determines, in large part, both the forces imposed on the blade and its mechanical strength and resonant frequencies, as well as the thermodynamic performance of the blade. These considerations impose constraints on the choice of blade airfoil shape so that, of necessity, the optimum blade airfoil shape for a given row is a matter of compromise between its mechanical and aerodynamic properties.
It is therefore desirable to provide a row of steam turbine blades that provides good thermodynamic performance while minimizing the stresses on the blade airfoil and root due to centrifugal force and avoiding resonant excitation. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The present invention relates generally to power factor correction. More particularly, the present invention concerns high speed power factor correction in devices such as regulated power supplies, and methods for operating such devices.
2. Description of Related Art
Electric power is often provided as alternating-current (“AC”) power in the form of time-varying currents and voltages. Typically, the AC power is furnished by providing a supply voltage that varies over time at a fundamental supply frequency fAC. In North America, for example, AC power is typically provided at a supply voltage having a fundamental supply frequency fAC of 60 Hertz. In European countries, the fundamental supply frequency fAC is typically 50 Hertz.
FIG. 1 illustrates a simplified diagram of a system 100 for supplying AC power to a remote load 120. The load 120 may for example be a computer, a television, a household appliance, or any other electronic device which requires power to operate.
A power supply source 110, which may be a generator at the location of a utility company, provides power by generating an AC supply voltage VAC(t) at a fundamental supply frequency fAC such as 60 Hertz. The supply voltage VAC(t) from the power supply source 110 is then distributed to the load 120 via a transmission line of a power distribution system 140. Although not illustrated in the simplified diagram of FIG. 1, the power distribution system 140 may include transformers and other components utilized in the distribution of power.
The supply voltage VAC(t) is delivered to the load 120 to induce a load current ILD(t) to flow between the power supply source 110 and the load 120 via the power distribution system 140, thereby delivering power to the load 120. The power generated by the power supply source 110 and distributed over the power distribution system 140 is the ‘apparent power’ delivered to the load 120. In comparison, the portion of the apparent power that, when averaged over time, results in a net transfer of energy into the load 120 is the ‘actual power’ consumed by the load 120. The actual power may for example be consumed by the load 120 by the conversion of the electrical energy into non-electrical energy such as heat, light or mechanical energy.
Ideally, all of the apparent power delivered to the load 120 is consumed as actual power, so that power which has been generated and distributed to load 120 is not wasted. However, typically the actual power is less than the apparent power. In other words, the power consumed by the load 120 is less than the power that must be generated and delivered to the load 120.
Power factor is defined as the ratio of the actual power to the apparent power, and is a dimensionless number between 0 and 1. The value of the power factor is thus a measure of the power consumption efficiency of the load 120. When all of the apparent power is consumed as actual power by the load 120, the power factor is 1. A lower power factor for the load 120 will require more apparent power, and thus draw more load current ILD(t), for the same actual power consumed. Although not utilized by the load 120, this higher apparent power in the form of higher load current ILD(t) still must be generated by the power supply source 110 and distributed over the power distribution system 140. As such, this higher apparent power is subject to losses in the power generation and distribution processes. This places a heavy stress on the power supply source 110 and the power distribution system 140, and may require more expensive generation and distribution equipment. It is therefore desirable for the power factor of the load 120 to be as close to 1 as possible.
The power factor of the load 120 is dependent on the time-varying relationship between the supply voltage VAC(t) and the load current ILD(t), which in turn depends on the electrical characteristics of the load 120. Ideally, the load 120 emulates the electrical characteristics of a resistor. In such a case, the supply voltage VAC(t) and the load current ILD(t) are directly proportional and change polarity at the same instant in each cycle of the waveform, as shown in FIG. 2A. As a result, power flows in a single direction from the power supply source 110 into the load 120 at each instance in time, such that all of the apparent power is consumed as actual power. This results in a power factor of 1 for the load 120.
Typically, however, the load 120 is not composed entirely of resistive elements. Instead, the load 120 may include components which can cause the power factor to be less than 1. These components may include reactive components such as capacitors or inductors which temporally store a portion of the apparent power as energy in electric and magnetic fields. Rather than being consumed as actual power, this stored energy can then be returned back to the power supply source 110 a fraction of a second after it is stored. In other words, these reactive components can result in power flowing both from the power supply source 110 to the load 120, and from the load 120 to the power supply source 110. This returned power is non-productive power which, although not consumed by the load 120, must still be generated by the power supply source 110 and distributed over the power distribution system 140. In such a case, the apparent power is greater than the actual power, resulting in a power factor less than 1.
Non-linear components within the load 120 which interrupt or otherwise distort the waveform of the load current ILD(t) can also cause the power factor to be less than 1. For example, the load 120 may consist of an electronic device such as a computer or household appliance which requires direct-current (“DC”) power to operate. In such a case, a power supply circuit within the load 120 converts the AC power provided by the power supply source 110 into DC power. The power supply circuit typically converts the AC power into DC power using a rectifier circuit which includes diodes. The diodes in the rectifier circuit can result in the load 120 drawing a high load current ILD(t) only at the peaks of the supply voltage VAC(t), and drawing substantially zero load current ILD(t) at other instances in time. This results in the load current ILD(t) having a highly non-sinusoidal waveform as shown in FIG. 2B. The high peak currents in the load current ILD(t) result in significant power loss within the power distribution system 140 and place a heavy stress on the power supply source 110 and the power distribution system 140.
The distorted load current ILD(t) also results in the load current ILD(t) having higher frequency components at integer multiples of the fundamental supply frequency fAC. For example, if the fundamental supply frequency fAC is 60 Hertz, the distorted load current ILD(t) can include components at 60 Hertz, 120 Hertz, 180 Hertz, 240 Hertz, etc.
The component of the load current ILD(t) at the frequency fAC is referred to herein as the fundamental component ILD0(t). A component of the load current ILD(t) at frequency (m+1)fac, where m is a positive integer greater than or equal to 1, is referred to herein as the mth overtone component ILDm(t). The load current ILD(t) is therefore a superposition of the fundamental and overtone components. This can be represented mathematically as:
I LD ( t ) = I LD 0 ( t ) + ∑ m = 1 M I LDm ( t ) Eq . ( 1 ) where M is the total number of overtone components ILDm(t) within the load current ILD(t). The value Im at a given time to is the amplitude of the overtone component ILDm(t=t0) at time t=t0.
Although present within the load current ILD(t), the overtone components ILDm(t) are not consumed by the load 120 as actual power. In other words, the power within each of the overtone components ILDm(t) is non-productive power which, although not consumed by the load 120, must still be generated by the power supply source 110 and distributed over the power distribution system 140. As such, the presence of these overtone components ILDm(t) in the load current ILD(t) results in an apparent power greater than the actual power, thereby resulting in a power factor less than 1.
A power factor correction (PFC) circuit may be implemented within the load 120 to improve the power factor. The PFC circuit regulates the load current ILD(t) in an attempt to make the shape of the load current ILD(t) match the sinusoidal waveform of the supply voltage VAC(t). In doing so, the PFC circuit attempts to remove or suppress the overtone components ILDm(t) and obtain a power factor of 1.
The PFC circuit may control the shape of the load current ILD(t) via an adaptive feedback loop. The adaptive feedback loop is used to adjust the parameters of a control signal based on a measurement of the values of the overtone components present in the load current ILD(t). The control signal is then utilized to regulate the load current ILD(t) drawn by the load 120 such that the load current ILD(t) is directly proportional to, and in phase with, the supply voltage VAC(t). See, for example, U.S. Pat. No. 7,719,862, the disclosure of which is incorporated by reference herein.
An adaptive feedback loop can provide excellent steady-state power factor correction performance, thereby enabling efficient power consumption by the load 120 and reducing the stress on the power supply source 110 and the power distribution system 140. However, the transient response performance due to the delay introduced by the adaptive feedback loop continues to limit the overall power factor correction performance.
Transient events can occur in the system 100 when the electrical characteristics of the load 120 suddenly change. This can occur for example if the load 120 is turned on or off by a user. Transient events may also occur in the form of power supply source 110 glitches or surges. Due to the delay introduced into the power factor correction process by the adaptive feedback loop, the PFC circuit may not be able to adjust the load current ILD(t) quickly enough to maintain a power factor correction at or near 1. For example, due to the delay, the control signal not be adjusted until one-half cycle of the supply voltage VAC(t) or longer following a transient event. As a result, these transient events distort the load current ILD(t) and result in overtones components ILDm(t). This in turn causes the power factor of the load 120 to temporarily decrease, consequently decreasing the power consumption efficiency of the load 120 and increasing the stress on the power generation and distribution processes.
It is therefore desirable to provide systems and methods for high speed power factor correction that address the performance limitations associated with changes in the operating conditions of a load or other transient events. | {
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In traditional computer-based storage systems, data is typically stored in sophisticated systems with layers of protections, backups systems, and encryption algorithms. The rise of wireless technologies and peer-to-peer (P2P) delivery systems is forcing the IT industry to decentralize infrastructure and its applications. Specifically, static physical infrastructures are being replaced with remote virtual environments that make traditional network, data, and applications obsolete. To this extent, even hardware supporting the traditional infrastructure is not scalable and proportional to deliver and meet the demands of P2P environment requirements. As such, conventional IT concepts are changing in an attempt to adopt a new model that provides a more scalable, and secure virtual infrastructure.
The above-incorporated patent applications all take various steps towards providing such an infrastructure. For example, U.S. patent application Ser. No. 10/856,684 (cross-referenced and incorporated above), avoids data loss by providing a wireless sensor network in which a plurality of peers/motes/nodes are interconnected (e.g., on a peer-to-peer basis). To store a data set within the network, the data set is broken up into data components, which are then stored among the nodes. Storage of the data components typically occurs by following a routing path through the network according to a routing table or the like. As the path is followed, the data components are stored among the nodes. Other examples of sensor based detection systems are described in U.S. Pat. No. 6,169,476 B1, and U.S. Pat. No. 6,293,861 B1, both of which are herein incorporated by reference.
Under U.S. patent application Ser. No. 10/946,714 (cross-referenced and incorporated above), a sensor network comprising a plurality of peer-to-peer nodes is provided. Each node in the network includes, among other things, a sensor for detecting environmental factors. When a potential failure is detected within a node, the node will query its neighboring nodes to determine whether they have the capability to store any data component(s) currently stored within the potentially failing node. Based on the querying, the data component(s) in the potentially failing node are copied to one or more of the neighboring nodes. Thereafter, details of the copying can be broadcast to other nodes in the network, and any routing tables that identify the locations of data components stored throughout the sensor network can be updated.
Under U.S. patent application Ser. No. 10/972,610 (cross-referenced and incorporated above), an autonomic sensor network ecosystem is provided. Such autonomic sensor network ecosystem includes: (1) a set (e.g., one or more) of sensor networks for storing data components; (2) a set of sensor collector information gateways in communication with the sensor networks; and (3) a set of enterprise gateways and storage hubs (hereinafter referred to as enterprise gateways) in communication with the micro grid gateway.
As advanced as these technologies have become, there still exists a need for a further evolution of the autonomic sensor network ecosystem. Specifically, a need exists for a method, system and program product for deploying (e.g. resources), allocating and addressing threats for an autonomic sensor network ecosystem. | {
"pile_set_name": "USPTO Backgrounds"
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1. Field of the Invention
This invention relates to novel chemical compounds, useful as optical indicators of cytochrome P450 activity, and especially to fluorogenic indicators of cytochrome P450 activity. More specifically, the invention relates to ether-containing compounds of the generic structure Y-L-Q, and to methods for assaying substrates and inhibitors of cytochrome P450 enzymes using these compounds in traditional assay formats, as well as in high and ultra high throughput screening formats.
2. Description of the Related Art
The cytochrome P450 enzyme (CYP450) family comprises oxidase enzymes involved in the xenobiotic metabolism of hydrophobic drugs, carcinogens, and other potentially toxic compounds and metabolites circulating in blood. It is known that the liver is the major organ for xenobiotic metabolism, containing high levels of the most important CYP450 mixed-function oxygenases. There are numerous human P450 enzyme sub-families, often termed "isozymes" or "isoforms." Those of the CYP 3A4, CYP 2D6, CYP 2C, CYP 2A1 and CYP 2E1 subfamilies are known to be important in drug metabolism. See, e.g., Murray, M., 23 Clin. Pharmacokinetics 132-46 (1992). Of these isoforms, CYP 3A4 is by far the major isoform in liver and the small intestines, comprising 30% and 70% respectively of the total CYP450 protein in those tissues. Based primarily on in vitro studies, it has been estimated that the metabolism of 40% to 50% of all drugs used in humans involve CYP 3A4 catalyzed oxidations. See Thummel, K. E. & Wilkinson, G. R., In Vitro and In Vivo Drug Interactions Involving Human CYP 3A, 38 Ann. Rev. Pharmacol. Toxicol., 389-430 (1998).
Efficient metabolism of a candidate drug by a CYP450 enzyme may lead to poor pharmacokinetic properties, while drug candidates that act as potent inhibitors of a CYP450 enzyme can cause undesirable drug-drug interactions when administered with another drug that interacts with the same CYP450. See, e.g., Peck, C. C. et al, Understanding Consequences of Concurrent Therapies, 269 JAMA 1550-52 (1993). Accordingly, early, reliable indication that a candidate drug interacts with (i.e., is a substrate or inhibitor of) a CYP450 may greatly shorten the discovery cycle of pharmaceutical research and development, and thus may reduce the time required to market the candidate drug. Consequently, such earlier-available, reliable CYP450 pharmokinetic information may result in greatly reduced drug development costs and/or increased profits from earlier market entrance. Furthermore, such earlier-available, reliable CYP450 pharmokinetic information may allow a candidate drug to reach the public sooner, at lower costs than otherwise feasible. Accordingly, extensive pharmacokinetic studies of drug interactions in humans have recently become an integral part of the pharmaceutical drug development and safety assessment process. See, e.g., Parkinson, A., 24 Toxicological Pathology 45-57 (1996). Methodologies are therefore desired that will allow for (1) the more rapid acquisition of information about drug candidate interactions with CYP450 enzymes, earlier in the drug discovery process than presently feasible, and hence will allow for (2) the earlier elimination of unsuitable compounds and chemical series from further development efforts.
The need for information regarding drug candidate/CYP450 interactions has created a concurrent need for assays sensitive enough to test, in a cost-effective manner, vast arrays of compounds for interactions with the major human CYP450 enzymes involved in drug metabolism. Certain known techniques, including (1) CYP450 inhibition assays in which the metabolism of known CYP450 metabolite in the presence of the test compound, followed by quenching of the enzyme reaction and analysis of the extent of metabolism, (2) CYP450 metabolism of radioactively labeled test compound analogues, and (3) in vivo "cassette" dosing of animals (usually rats, dogs, or monkeys), see Berman, J. et al., Simultaneous Pharmacokinetic Screening of a Mixture of Compounds in the Dog using API LC/MS/MS Analysis for Increased Throughput, 40 J. Medicinal Chemistry, 827-29 (1997), are not amenable to adaptation to miniaturization, or to the other requirements of high or ultra high throughput screening.
However, optical assays employing, for example, chromophores or luminescent phenols, and especially fluorescence-based assays are amendable to adaptation to miniaturization and high or ultra high throughput screening. Particularly, fluorescence-based assays have been used in pharmacokinetic studies of drug interactions in humans, more particularly in assays involving human hepatocyte cultures, where the number of available cells is severely limited. See Donato, M. T. et al., 213 Anal. Biochem. 29-33 (1993).
Specifically, fluorogenic cytochrome P450 substrates have been commercially available for a number of years from, for example, Molecular Probes, Inc. (Eugene Oreg.), SIGMA (St. Louis, Mo.), and more recently, GENTEST Corp. (Woburn, Mass.). Generally, these known fluorogenic CYP450 substrates are ether derivatives of well-known phenoxide type fluorophores, including: 7-hydroxycoumarin, fluorescein, and resorufin. Thus, generally, the CYP450 enzymes will catalyze a dealkylation reaction and convert the relatively non-fluorescent ether substrate into a relatively more highly-fluorescent phenoxide-containing product.
However, even the most recently developed fluorogenic CYP450 substrates either have relatively poor kinetics, or the enzymatic products do not have the desired physical and optical properties to allow reduction of the amount of enzyme needed to levels that would make large scale screening affordable and feasible. More specifically, these fluorogenic CYP450 substrates exhibit relatively poor turnover rates, poor aqueous solubility, low extinction coefficients and quantum yields, and/or weak fluorescence of the resultant phenolic dye. Furthermore, certain of these fluorogenic CYP450 substrates are excited in the ultraviolet, as opposed to visible, spectrum and therefore their signals are often masked by background stemming from the unreacted test compound. Finally, most of these fluorogenic CYP450 substrates are not specific for the CYP450 isozyme they are meant to detect, and therefore cannot be used for measurement in human liver microsomal preparations, a preferred analytical method that avoids potential artifacts caused by the alternative method of using an insect cell microsomal preparation. See Palamanda J. R. et al., Validation of a rapid microtiter plate assay to conduct cytochrome P450 2D6 enzymes inhibition studies, 3 Drug Discovery Today, 466-470 (1998). For these and other reasons, there exists an unfulfilled need for optical, and especially fluorogenic, CYP450 substrates that exhibit CYP450 isozyme-specificity, improved kinetics, and yield enzymatic products having improved physical and optical properties for use in the screening of CYP450/drug candidate interactions, especially for use in high or ultra high throughput screening, and as part of the drug discovery process. | {
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The present invention is directed to a method of installing a glass window in a soft auto top, and more particularly, to the incorporation of a metal ring between the soft top material and the glass window for proper bonding.
The attachment of a glass window in a soft auto top has been an age-old problem. Several previous methods of installing a glass window to a soft top include bonding the glass directly to the soft top using various glues, silicones or other similar bonding agents. Another previous method includes taping the window directly to the soft top using double sided tape, such as 3M VHB tape. Still, other methods include bonding the window to the soft top using a thermally activated adhesive or tape, molding or encapsulating the window into the soft top, or clamping the window into the soft top using various fasteners.
Typically, soft auto tops are constructed using vinyl or canvas. Both of these materials are very difficult, if not impossible, to bond to a glass surface. Therefore, soft tops have traditionally had windows constructed of plastic so that they could be sewn into the auto top. However, the plastic windows tended to scratch and discolor easily, leading to severe impairment of vision. Because of this problem, consumers demanded auto tops having glass windows installed. This demand lead to auto top manufacturers to utilize the previously identified methods to install a glass window into a soft top, however, these prior methods have had numerous disadvantages and problems, including, a high rate of failure of the bond holding the window to the top, resulting in the window falling out of the top and/or leaking water into the vehicle. Another problem associated with prior methods is that they required expensive tooling and equipment to achieve the required bond between the glass and the soft top material. Prior methods required a high degree of skilled labor and these processes were very labor intensive. Yet, another problem is that it is difficult to replace a glass window in the same soft top in the event a window is broken or to have more than one window installed in the top.
Aesthetically, the outside joint between the soft top and the window is cosmetically unappealing. In addition, the use of clamps and fasteners are expensive when needed in low volumes, such as the after market or replacement top segment, which makes the top more expensive and less affordable for consumers. Consequently, a need exists for a new method for installing a glass window in a folding or removable soft auto top which addresses the problems associated with prior methods. | {
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Recently, methods for transmitting coded data, compressed efficiently based on inter-frame prediction, are used as a method for efficiently transmitting moving image data in many cases. Those methods encode prediction parameters and predictive residual images, obtained by predicting coded images from the temporally preceding and following frames, to reduce the information amount of moving image data that has a high time correlation. In addition, those methods efficiently compress predictive residual image data through transform coding or quantization to enable the transmission of moving image data at a narrow transmission band.
Typical examples of those methods are those using compress and encode methods such as MPEG (Moving Picture Experts Group)-1, MPEG-2, and MPEG-4. Those compress and encode methods perform inter-frame prediction for input image frames through motion compensation on a basis of a fixed-size rectangular area unit, called a macro block, and perform variable-length coding for the obtained motion vector and the signal data compressed by executing two-dimensional discrete cosine transform and quantization for the predictive residual image data.
There are many methods for distributing moving image data, obtained by the compression described above, to an IP (Internet Protocol) network that uses the packet switching method and it is expected that the IP-based distribution of moving images will also become popular on wireless transmission lines.
There are a file download method and a streaming method for distributing such moving image data. In the file download method, all of a predetermined file is distributed and then reproduced. When transmitting via a wireless transmission line, the file download method is employed in many cases to allow an action to be taken against a wireless error or loss that may be generated. On the other hand, because it takes long for the file download method to start reproducing moving images, the streaming method that can start reproduction before completely receiving moving image data is also used.
However, in the file download method, it is basically required that the download be started, not from a moving image data part requested by the user, but from the start of the file. In the streaming method, too, the reception and reproduction of moving image data from any desired position cannot be started or limited in some cases if there are continuous inter-frame coded frames.
Therefore, to decode and reproduce moving image data from any desired position, the sending side sends moving image data in which intra-frame coded data is inserted between inter-frame coded data at an appropriate time interval. A technology is also developed for use on the receiving side to divide received moving image data into multiple files and record them and to decode and reproduce the moving image data from an intra-frame coded data position included in the data read from any desired file of the files (for example, Patent Document 1).
Another known method is that, when an intra-frame coded frame is inserted at an interval of a predetermined frame period and a random access point is set, a new intra-frame coded frame is inserted and an intra-frame coded frame in the immediately preceding frame period is replaced by an inter-frame coded frame before coding (for example, Patent Document 2). Patent Document 1: Japanese Patent Kokai Publication No. JP-A-9-18881 (FIG. 1) Patent Document 2: Japanese Patent Kokai Publication No. JP-A-11-275583 (FIGS. 3 and 8) | {
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Over a million and a half miles of pipeline are buried in the United States alone. Such pipelines are used to transport hazardous gases and liquids, many at high pressures on the order of 1000 psi. The majority of these pipelines involve natural gas transport. There are approximately 1000 pipeline failures reported each year with a few involving loss of life or significant property loss.
Corrosion of the pipe material is the main cause of pipeline failure. Corrosion is an electrochemical process involving metal oxidation and mass and charge transport between an electrode and a surrounding electrolyte. The charge transport implies that an electrical current flows between locations on the pipe and from the pipe to external electrodes. A metallic pipeline can be an electrode and the soil an electrolyte so that the pipeline buried in soil forms the elements of an electrolytic cell. Some corrosion arises from the naturally occurring processes at specific locations on the pipe involving electrical current flow into the ambient soil electrolyte via the corrosion reaction. Corrosion is often additionally caused or accelerated by voltages applied to a local region of the pipe by man-made structures, including local transit systems, power distribution systems and other terrestrial sources of stray voltages and currents.
As a result, early detection and control of corrosion are necessary to maintain the integrity of a pipeline. To accomplish this, pipelines are periodically tested or continuously monitored for indications of corrosion activity and where necessary the electrochemical environment of the pipeline is modified by established control techniques.
Corrosion monitoring has been conventionally accomplished by conducting pipe to soil potential surveys to determine whether the potential difference between pipe and soil exceeds a specified threshold potential of 850 millivolts relative to the copper-copper sulfate couple and generally defined as adequate to prevent corrosion. Typically the pipe to soil potential measurements are accomplished using a copper/copper sulfate electrode half cell, wherein one electrode is connected to the pipe and the other is in contact with the earth above the pipe. Measurements of this potential are made at intervals from several feet to fifty feet or more. Monitoring of on-pipe currents is typically accomplished with the use of two electrodes physically bonded to the pipe at selected locations with a typical spacing of 200 feet.
These currently available methods suffer limitations. First, the pipe to soil corrosion potential method does not determine the corrosion rate. Rather, it indicates a condition where corrosion could take place electrochemically. In practice, pipelines exhibiting a corrosion potential greater than the -0.85 V /CuSo.sub.4 limit cited previously have been found to be at risk of having unacceptable corrosion. Conversely, however, corrosion is a current phenomenon and the corrosion rate is proportional to the density of current between pipe and soil. There is a direct proportional relationship between the charge transfer processes responsible for the current and the metal mass transferred from the pipe electrode and the corrosion rate. In conventional electrochemical practice and in the present invention the central measured parameter is the ratio of the current density to the interfacial voltage between pipe and electrolyte viz the interfacial admittance or the inverse polarization resistance conventionally denoted as R.sub.p.
Additionally, another limitation is that the measured pipe to soil potential is an average over a relatively large length of pipe because of the need for direct connection to the pipe to effect these measurements and the soil conditions from pipe to the earth surface. As a result, small regions of high corrosion rate which could lead to pipe failure may not be found.
Furthermore, the use of IR drop electrodes, which are physically bonded to the pipe at selected locations, while providing an effective measurement of pipe current, is expensive and is limited because of the expense and the need to provide specific monitoring sites. In particular, in present practice the two electrodes bonded to the pipe which comprise an IR drop pair, are spaced 200 feet apart. This means that only currents which flow continuously over this distance are monitored. In areas where many pipes are present or where current loss from the pipe is suspected, the spatial resolution of this technique is inadequate.
The industry has applied negative voltages between pipe and soil (cathodic protection) to achieve protection as illustrated in FIG. 1. However, there is considerable uncertainty as to the actual value of the potential at specific pipe locations and as to what voltage level provides adequate protection for the pipe.
There are several monitoring techniques known from conventional electrochemistry which provide information which is directly related both to the presence of active corrosion and to corrosion rate monitoring. Since corrosion is a process involving both mass and charge transfer between a corroding solid and its environment, all of these methods involve measurement of the exchange current and more particularly the interfacial impedance given by the ratio of the current to the interfacial voltage.
There has been a report of the use of a magnetic field detector to observe corrosion currents in a small electrochemical cell in a laboratory environment. However, the authors did not monitor corrosion rates, determine interfacial impedances or suggest that corrosion rates could be determined by magnetic field detection. This report consisted of an article entitled "Detection of Magnetic Fields Generated by Electro-Chemical Corrosion" in the August 1986 issue of the Journal of the Electrochemical Society. Detection consisted of observing temporal changes in naturally occurring corrosion currents flowing between two dissimilar metals in contact with an aqueous electrolyte. There was no use of an impressed voltage across the cell such as would have been required to conduct classical electrochemical corrosion monitoring experiments. The lack of this impressed voltage also means that correlation based signal processing techniques cannot be employed. In our work these signal processing techniques are used to separate corrosion induced magnetic signals in practical pipeline applications from other magnetic signals associated with geomagnetic noise, magnetic materials and structures in the earth and environmental noise associated with automobiles and other moving objects.
Magnetic detection has also been used for many years for monitoring the current distribution on buried pipelines. An article entitled "Electromagnetic Techniques for Monitoring Pipeline Coatings", presented as paper 311 at a corrosion conference in March 1987, is a recent example of this type of application. In this paper N. Frost suggested that an AC potential can be impressed between a pipeline and an electrode buried in the soil and spaced from the pipeline. The current distribution of the current along the pipe is detected via a magnetic sensor which monitors the AC magnetic field produced by the AC current on the pipe. He illustrates the positioning of an inductive (coil) type magnetic sensor to detect on-pipe current and especially the decrement in on-pipe current which occurs as current leaks into the soil through the coating on the pipe. Using the change in the gradient of the on-pipe current with position above the pipe, he shows that coating breaks can be detected. What he has not shown .is neither the detection of the transverse current leaving the pipe using magnetic sensing means nor the use of either the on-pipe or transverse current to determine the electrochemical impedance of the interface at the pipe where corrosion is taking place. The impedance measurement is essential to the application of magnetic sensing for corrosion detection and corrosion rate monitoring. Moreover, it is required for the quantitative determination of corrosion activity on the buried pipeline.
The Frost system is based upon the analysis that electrical current leaks preferentially from breaks or holidays in the protective pipeline coating because these exhibit substantially reduced electrical resistance. While a completely protected pipeline would exhibit a substantially constant current gradient along its length as a result of a relatively uniformly distributed current leakage, a holiday can be detected by a substantial change in the current gradient plotted as a function of distance along the pipe.
One problem with a system which looks only at on-pipe current is its low sensitivity. That problem arises because the differential changes in on-pipe current are relatively small compared to the total on-pipe current. Thus, the environmental noise, such as changes in the earth's magnetic field, stray currents, and cathodic protection currents, makes it difficult to utilize such a system.
The prior art has also suggested a variety of electrochemical measurement techniques for determining the interfacial impedance associated with the pipe/soil interface. For example, there is the Tafel extrapolation method in which the interface is perturbed with a DC voltage. The linear polarization method uses a small ramp function potential applied to the interface. The small amplitude cyclic voltammetry method uses a sawtooth which is a repeated ramp function. Others have suggested impulse measurements and the use of harmonic signal analysis.
An example of the latter system is "Electro-Chemical Impedance Spectroscopy" Electro-Chemical Impedance Spectroscopy, abbreviated EIS is a linear AC impedance method which is a conventional electrochemical technique for measuring the chemical condition at an electrode/electrolyte interface. Its application to measuring the corrosion rate at pipe/soil interface was suggested in a published report entitled "Effectiveness of Cathodic Protection" by Thompson, Ruck, Walcott and Koch and published in 1987. In this method a small amplitude, AC potential is applied by a source between a direct connection to the pipe and an electrode buried in the soil and spaced from the pipe. The amplitude and phase of the resulting source current with respect to the applied source voltage is detected for each of a plurality of source signal frequencies.
The total electrical current passing through the pipeline, soil, and electrode is assumed to be reasonably controlled by Randle's equivalent circuit or other equivalent circuit, several of which have been developed by the prior art workers. For example, equivalent circuits are discussed in an article in Corrosion Science entitled "Utilization Of The Specific Pseudo-Capacitance For Determination Of The Area Of Corroding Steel Surfaces" published in the August 1988 edition, volume 44, No. 8 and in a further article in the same issue entitled "Equivalent Circuits Representing The Impedance Of A Corroding Surface"
However, to adequately represent the current loss distribution on a large extended structure such as a pipeline, an equivalent circuit model such as that shown in FIG. 10 is required. At each location along the pipe there is an impedance value describing local current flow and hence local corrosion activity.
In EIS, the amplitude and phase data for the current at each frequency and applied potential are used to calculate a complex impedance for each frequency, including both the amplitude and phase of that impedance. This measured impedance of the circuit to which the AC source is applied for each of several frequencies may then be equated with the algebraic expression for the impedance of the equivalent circuit and these simultaneous equations are solved for values of the circuit elements. As is described in the prior art, the circuit elements, and particularly the interfacial resistance and capacitance along the pipe to soil interface provide indications of both interface condition, that is the presence or absence of holidays and corrosion, and also the corrosion rate. Often the process of impedance calculation is carried out under computer control.
A principal problem, however, with the EIS system and other prior art electrochemical systems described above is that they require physical contact with the pipe. Operationally, this is a major limitation when the pipe is under pavement or otherwise inaccessible. In addition, conventional measurements are applicable only to total currents passing through a relatively long span of pipe. Thus, the measurements are essentially an average over a long span of pipe and do not provide information about the local condition of the pipe.
Thus, the disadvantages of conventional electrochemical methods for pipe corrosion detection are that they determine an average corrosion rate over an entire pipe length and therefore obscure small regions of high corrosion activity; they are not directly applicable under conditions of cathodic protection; and errors result from soil resistivity effects.
There is therefore a need for an improved system overcoming the above mentioned disadvantages of the current technology and providing for a non-contact system which can measure local current distribution and local impedance values. | {
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1. Field of the Invention
The invention relates to a medical device, and more particularly, the invention relates to a medical device for delivering a non-biodegradable bulking composition to a urological site to treat urinary incontinence.
2. Brief Description of the Related Art
Urinary incontinence is an extremely common problem especially in women. In particular, many women suffer from stress incontinence. In this condition, the pelvic-floor tissues which support the urethra are weakened by, for example, childbirth or obesity. As a result, when pressure is exerted on these tissues by coughing, lifting, etc., urine is involuntarily discharged from the bladder through the urethra.
The initial treatment for stress incontinence typically consists of exercises to strengthen the pelvic-floor muscles. If these exercise are ineffective, open surgical repair of the bladder neck is often attempted. However, such surgical repair procedures are not successful for all patients. Moreover, there are always certain risks associated with open surgical procedures, such as infection, risks of anesthesia, etc.
As an alternative to surgical repair, urinary incontinence has been treated by periurethral injection therapy, in which a substance is injected into the tissue surrounding the urethra, i.e., the periurethral tissue, to add bulk to this tissue. The aim of this treatment is to restore the proximal urethra to its proper normally closed condition and to keep it closed during coughing, straining, or exercise. The injected substance compresses the urethra at the level of the bladder neck thus impeding the involuntary flow of urine from the bladder.
Many injectable substances have been tried for this purpose with varying results. For example, in the first half of the twentieth century sclerosing solutions, such as sodium morrhuate or cod liver oil were injected into the anterior vaginal wall. An inflammatory response developed with secondary scarring which resulted in compression of the incompetent urethra. Although this material was successful in curing incontinence in some patients, complications included pulmonary infarction and cardiac arrest. Similarly, paraffin and other sclerosing solutions have been tried with poor results.
More recently, polytetrafluoroethylene particles (TEFLON(trademark), POLYTEF(trademark)) have been used as an injectable material for the correction of urinary incontinence with a success rate of from 30% to 86% in some studies. However, these particles have subsequently been demonstrated to generate foreign body granulomas and to migrate to distant organs, such as the lungs, liver, spleen and brain. Accordingly, the use of polytetrafluoroethylene particles is currently disfavored.
Another injectable material that has been used recently for the treatment of urinary incontinence is glutaraldehyde cross-linked bovine dermal collagen. However, a major problem associated with the use of collagen materials is the tendency of the implant to decrease in volume over time thereby necessitating retreatment. In addition, collagen has been associated with adverse immune responses and allergic reactions to bovine dermal collagen have been described.
Various other injectable substances have been reported or proposed as implant materials for the treatment of bladder conditions, such as vesicoureteral reflux. These substances include polyvinyl alcohol foam, glass particles, a chondrocyte-alginate suspension, and a detachable silicone balloon.
In addition to the various problems associated with many of the substances used to treat urinary incontinence, the methods currently employed for delivering injectable materials to the periurethral tissue have certain disadvantages. In particular, the amount of material necessary to compress the urethra must typically be estimated by observing the compression of the urethra wall using a cystoscope or endoscope. If an insufficient amount of material is injected in the first procedure, top-up injections administered in subsequent procedures may be necessary. In addition, the materials which are delivered may be absorbed by the body over time requiring retreatment. Other materials which are used are hydrateable and swell within the body causing difficulty in predicting a final size of the injected material.
U.S. Pat. Nos. 5,755,658 and 5,785,642, which are incorporated herein by reference in their entirety, describe methods of delivering a composition comprising a biocompatible polymer and a biocompatible solvent to the periurethral tissue. The biocompatible solvent is miscible or soluble in the fluid of the periurethral tissue and, upon contact with these fluids, the biocompatible solvent quickly diffuses away. Upon diffusion of the solvent, the biocompatible polymer precipitates to form an occlusion in the periurethral tissue which compresses the urethra thereby preventing or reducing the involuntary leakage of urine from the bladder.
However, there are certain drawbacks to the use of conventional delivery systems with the biocompatible polymer composition. In particular, the biocompatible polymer composition is injected into the periurethral tissue as a flowable composition which may not solidify instantaneously. Accordingly, it would be desirable to provide faster solidification and better control of the delivery of the biocompatible polymer composition. It would also be desirable to provide these advantages for other compositions which are delivered as two liquids to form a solid.
The present invention relates to a medical device for delivery of a biocompatible polymer composition to the periurethral tissue to treat urinary incontinence.
In accordance with one aspect of the present invention, a medical device includes a needle and an inner cannula positioned within the needle lumen and movable longitudinally in the needle lumen. The inner cannula has a lumen for delivering a first fluid and the needle has a lumen for delivering a second fluid. The inner cannula has a cannula tip configured to detach a mass from the needle when the inner cannula is moved from an extended position at which the cannula tip extends from a distal end of the needle to a withdrawn position at which the cannula tip is within the needle lumen.
In accordance with an additional aspect of the present invention, a medical device includes an inner cannula, an outer cannula coaxially surrounding the inner cannula, an injection hub connected to the inner and outer cannulas, and a movable piston within the injection hub. The piston is connected to the inner cannula for moving the inner cannula within the outer cannula, wherein the movable piston is actuated by a delivered fluid which is delivered through the inner or outer cannula.
In accordance with a further aspect of the invention, a device for delivering non-biodegradable bulking composition to a urological site includes a needle, an inner cannula longitudinally movable within the needle, the inner cannula having a distal end with a trumpet shaped tip, and an injection hub connected to the needle and inner cannula for delivery of first and second fluids through the needle and inner cannula. | {
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A position of a concrete placement form for reinforced concrete structures is held by horizontal and vertical frame materials so that this form is not displaced and deformed by a pressure of concrete in a fluid state during concrete placement. Further, the frame materials are bound by a bundling material for strut materials and a linear material such as a chain which is a tension material so that the frame materials are not displaced even though vibration or a pressure during concrete placement is applied thereto. Furthermore, in shipping transportation, a container to be transported is fastened with a wire rope or the like without looseness so that it cannot be displaced. Tensile force of these linear materials, e.g., a chain or a wire rope is adjusted by a tension tool such as a turnbuckle so as to prevent slack from being produced.
The turnbuckle is a tension tool which has a screw thread, to which a treaded rod of a right screw is screwed from one end thereof and a threaded rod of a left screw is screwed from the other end thereof, is formed at each of both ends of a body frame, and which moves positions of the threaded rods at both the ends closer to or away from each other by rotating the body frame. A locking portion such as a hook is formed at an end portion of each threaded rod, and the locking portion is locked with respect to a chain or a wire as a linear material whose tensile force is adjusted. The turnbuckle has an advantage that a length for pulling in the hooks at both the ends closer can be increased, whereas it has a problem that the number of times of rotation of the turnbuckle is increased and tensile force adjustment takes time and labor when the length for pulling in is long and that the body frame is close to the linear material and hence the body frame is hard to rotate when the linear material is not loose enough.
Thus, Japanese Unexamined Patent Application Publication No. 1992-300408 discloses the technology by which protruding portions are formed at a plurality of positions on an inner shaft along a body frame, notch portions are formed in an engagement plate placed at an end portion of an outer cylinder of the body frame, the inner shaft is axially slid along the body frame, the protruding portions are engaged with the notch portions, whereby a length between respective coupling tools formed at the end portion of the body frame and the end portion of the inner shaft can be adjusted. According to this technology, the length between the coupling tools at both the ends of the turnbuckle can be easily adjusted, whereas there is a problem that the number of components constituting the turnbuckle increases.
Further, Japanese Unexamined Patent Application Publication No. 2006-070572 discloses the technology of an adjustment tool that has hook portions on both a head side of a bolt and a distal end side of a shaft body of the bolt, attaches hooked cylindrical bodies freely fitted onto the shaft body, and fastens a nut, and thereby adjusts a distance between the two hooked cylindrical bodies to eliminate slack of a chain or the like for hanging a work platform.
According to this technology, since the pair of hooks are secured to lateral sides on the bolt head side and the bolt distal end side, and the bolt or the like cannot enter between the pair of upper and lower hooks. Furthermore, when the pair of hooks are arranged to face each other, the pair of hooks can be held in an opposed state, the hook on the bolt head side can be placed on the upper side, the hook on the bolt head side and the bolt shaft portion can be simultaneously held with one hand, the hook can be easily engaged with an upper link of the chain, and the hook on the bolt end side can be easily engaged with a lower link of the chain.
However, in case of a chain stretched with less slack, at the time of engaging the hook on the bolt head side with the upper link, the hook on the bolt distal end side that is in the freely fitted state interferes with the other link and rotates, and hence the hook is hard to be hooked. Moreover, after the hook on the bolt head side is hooked, the hook on the bolt distal end side must be held with one hand, a position of the link of the chain placed on the bolt distal end side must be adjusted with the other hand while sliding the bolt shaft along the cylindrical body on the bolt head side, the hook on the bolt end side must be fitted to the link while paying attention to prevent the hook on the bolt head side which has been hooked before the counterpart from coming off the link, and hence there is a problem that disposing the coupling tool is difficult. | {
"pile_set_name": "USPTO Backgrounds"
} |
1. Field of the Invention
The invention relates to newly identified mammalian chemosensory G protein-coupled receptors, to family of such receptors, and to the genes and cDNA encoding said receptors. More particularly, the invention relates to newly identified mammalian chemosensory G protein-coupled receptors active in taste signaling, to a family of such receptors, to the genes and cDNA encoding said receptors, and to methods of using such receptors, genes, and cDNA in the analysis and discovery of taste modulators. The invention provides in particular a DNA sequence encoding a novel human taste receptor identified infra as T1R2 and the corresponding receptor polypeptide.
2. Description of the Related Art
The taste system provides sensory information about the chemical composition of the external world. Mammals are believed to have at least five basic taste modalities: sweet, bitter, sour, salty, and umami. See, e.g., Kawamura et al., Introduction to Umami: A Basic Taste (1987); Kinnamon et al., Ann. Rev. Physiol., 54:715-31 (1992); Lindemann, Physiol. Rev., 76:718-66 (1996); Stewart et al., Am. J. Physiol., 272:1-26(1997). Each taste modality is thought to be mediated by a distinct protein receptor or receptors that are expressed in taste receptor cells on the surface of the tongue (Lindemann, Physol. Rev. 76:718-716 (1996)). The taste receptors that recognize bitter, sweet, and umami taste stimuli belong to the G-protein-coupled receptor (GPCR) superfamily (Hoon et al., Cell 96:451 (1999); Adler et al., Cell 100:693 (2000)). (Other taste modalities are believed to be mediated by ion channels.)
G protein-coupled receptors mediate many other physiological functions, such as endocrine function, exocrine function, heart rate, lipolysis, and carbohydrate metabolism. The biochemical analysis and molecular cloning of a number of such receptors has revealed many basic principles regarding the function of these receptors. For example, U.S. Pat. No. 5,691,188 describes how upon a ligand binding to a GPCR, the receptor undergoes a conformational change leading to activation of a heterotrimeric G protein by promoting the displacement of bound GDP by GTP on the surface of the Ga subunit and subsequent dissociation of the Ga subunit from the Gb and Gg subunits. The free Ga subunits and Gbg complexes activate downstream elements of a variety of signal transduction pathways.
Complete or partial sequences of numerous human and other eukaryotic chemosensory receptors are currently known. See, e.g., Pilpel, Y. and Lancet, D., Protein Science, 8:969-977 (1999); Mombaerts, P., Annu. Rev. Neurosci., 22:487-50 (1999). See also, EP0867508A2, U.S. Pat. No. 5,874,243, WO 92/17585, WO 95/18140, WO 97/17444, WO 99/67282. Because of the complexity of ligand-receptor interactions, and more particularly taste stimulus-receptor interactions, information about ligand-receptor recognition is lacking.
The identification and characterization of the GPCRs that function as sweet and umami taste receptors could allow for new methods of discovery of new taste stimuli. For example, the availability of receptors could permit the screening for receptor modulators. Such compounds would modulate taste and could be useful in the food industry to improve the taste of a variety of consumer products; e.g., improving the palatability of low-calorie beverages through the development of new artificial sweeteners.
In part, the present invention addresses the need for better understanding of the interactions between chemosensory receptors and chemical stimuli. The present invention also provides, among other things, novel chemosensory receptors, and methods for utilizing such receptors, and the genes a cDNAs encoding such receptors, to identify molecules that can be used to modulate chemosensory transduction, such as taste sensation. | {
"pile_set_name": "USPTO Backgrounds"
} |
The invention concerns a method of signal processing, wherein signals S are checked for belonging to objects of desired classes Zk and differentiated from objects in an undesired class ZA.
In order not to skip over any objects of relevance, segmenting algorithms produce, in general, a large number of hypotheses whose examination requires a large expenditure of time. Another disadvantage is that a segmenting algorithm can often only consider a small number of attributes of the object to be segmented, such as shape or color, in order to analyze in real time a complete picture or at least a region of a picture in which new objects can knowingly emerge. In the case of a segmentation of circular traffic signs in a street scene, the segmentation is performed, in general, via a Hough-transformation (K. R. Castelman; Digital Image Processing, Prentice Hall, New Jersey, 1996) or a distance transformation that is based upon a matching algorithm (D. M. Gavrilla; Multi-Feature-Hierarchical Template Matching Using Distance Transforms, IEEE Int. Conf. on Pattern Recognition, pp 439-444, Brisbane, 1998), all in order to find all shapes typical for a circular traffic sign.
For a classification, which follows such a segmentation, the principal problem is not the differentiation of the different objects of the class Zk (e.g. traffic signs) from each other, but rather the difficulty of differentiating the objects of this class Zk from the objects of the undesired class ZA. Therein the objects of the undesired class ZA consist of any image field which are selected by the segmentation algorithm due to their similarity to objects of the class Zk.
This leads to a two class problem, in which certainly only the class Zk is more or less locatable in the feature realm or set, while the class ZA is widely scattered over the feature set. Therein, in general, it is not possible to find a limited number of xe2x80x98typicalxe2x80x99 objects, that are associated with the class ZA. Were number of objects of the class ZA so limited, then it would be possible to generalize a classifier starting from a set of learning examples of the total variations of possible elements of the class ZA; assuming that objects are limited to those from a closed world (closed world assumption) from which the general classification theory originates is damaged in this case.
In reality, most of the objects produced by a segmentation algorithm belong to the class ZA. In the case of traffic sign recognition these are typically more than 95 percent, which further complicates the classification problem.
The task of the invention is to develop a signal processing method, which has high certainty while processing the signal in real time and avoiding a false classification of objects of the class ZA, i.e. that the probability is kept low that objects of class ZA will be falsely assigned to one of class Zk. | {
"pile_set_name": "USPTO Backgrounds"
} |
For expository convenience the present invention will be illustrated with reference to a paging system (the "Gaskill system") described in U.S. Pat. Nos. 4,713,808 and 4,897,835. However, it will be understood that the present invention is not so limited. The disclosures of U.S. Pat. Nos. 4,713,808 and 4,897,835 are incorporated herein by reference.
For purposes of the present discussion, it will be understood that the Gaskill system provides a paging system wherein a paging device is incorporated into a wristwatch. Paging information, together with time of day information, is transmitted by FM radio signal to each watch according to a time slot protocol. In accordance with this protocol, the watch includes a timing mechanism for activating a radio receiver and decoder of the watch during a time slot selected by the watch. The watch thereby activates its radio receiver and decoder to capture the radio signal data broadcast during its selected time slot.
A watch using the Gaskill system can maintain a higher degree of accuracy than a conventional time piece. For example, with a conventional time piece, even the slightest inaccuracy in its time keeping reference can be cumulative. The extent of error, or deviation from the actual time tends to grow over time. With a number of conventional time pieces placed side by side, the least significant digits, e.g., the seconds digits, will not change in synchronization. Even if conventional time pieces are set initially to identical time, the slightest inaccuracy in time keeping accumulates making impossible synchronized time displays.
Thus, inaccuracy of a time piece is observed by inspecting the time displayed by a number of such time pieces placed side by side. If the time pieces keep accurate time, this is reflected in simultaneous display updates by all time pieces. For example, the seconds display for all devices will change simultaneously if time is maintained accurately by all devices. Typically, however, such simultaneous display updating is not achieved, and if achieved such condition does not endure.
Accordingly, it is desirable to provide an accurate time keeping device whereby a group of such devices maintains time accurately and exhibits such accuracy by continued simultaneous display updating. | {
"pile_set_name": "USPTO Backgrounds"
} |
This section provides background information related to the present disclosure which is not necessarily prior art.
Blood transfusions are used to treat many disorders and injuries, such as in the treatment of accident victims and during surgical procedures. According to current American Red Cross statistics, about 5 million people receive blood transfusions each year, in the United States alone. Thus, health care systems rely on the collection and distribution of blood. Typically, blood is obtained from a donor and then processed and stored; units of stored blood or blood products are then taken from storage as needed and transfused into a patient in need. In some cases, the blood may be an autologous donation, where an individual donates blood in expectation of receiving his or her own blood by transfusion during a medical procedure.
Donated blood is typically processed into components and then placed in storage until needed. When a subject is in need of a blood transfusion, a unit of blood is commonly removed from storage, rejuvenated, washed, and resuspended in an appropriate solution. In some instances, the red blood cells were lyophilized prior to storage, in which case they need to be resuspended, washed, and then resuspended again in an appropriate solution. The resuspended red blood cells are then transfused into the subject. In either scenario, washing the red blood cells is traditionally a tedious, time consuming and multistep process that requires a great deal of tubing, and the use of expensive centrifuges with rotating seals to separate the cells from the wash solution. Therefore, there remains a need to streamline and simplify the process for washing red blood cells prior to transfusion. | {
"pile_set_name": "USPTO Backgrounds"
} |
With the advancement of technology, the use and popularity of electronic devices has increased considerably. Electronic devices are commonly used to transmit image data while videoconferencing. | {
"pile_set_name": "USPTO Backgrounds"
} |
Heretofore, machines for removing or stripping hide from animal carcasses for use in a meat-packing plant during the slaughtering process have been known. Such machines include a cantileverly mounted hide pulling drum that pivotally swings along a carcass hanging from its hind quarters and having the forelegs connected to chains during the hide-stripping operation. These machines, because of the cantileverly supported drum, must be heavily built and also require a considerable amount of floor area. They also require suspending the carcass at a sufficient distance from the machine so as to prevent interference between the movable parts of the machine and the carcass during the stripping operation. | {
"pile_set_name": "USPTO Backgrounds"
} |
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