A semiconductor structure including a uniform etch-stop layer. The uniform etch stop layer has a relative etch rate which is less than approximately the relative etch rate of Si doped with 7×1019 boron atoms/cm3. A method for forming a semiconductor structure includes forming a uniform etch-stop layer providing a handle wafer, and bonding the uniform etch-stop layer to the handle wafer. The uniform etch-stop layer has a relative etch rate which is less than approximately the relative etch rate of Si doped with 7×1019 boron atoms/cm3.

The invention relates to the field of etch-stop material systems on monocrystalline silicon.
Microelectromechanical systems (MEMS) form the bridge between conventional microelectronics and the physical world. They serve the entire spectrum of possible applications. MEMS include such varied devices as sensors, actuators, chemical reactors, drug delivery systems, turbines, and display technologies. At the heart of any MEMS is a physical structure (a membrane, cantilever beam, bridge, arm, channel, or grating) that is "micromachined" from silicon or some other electronic material. Since MEMS are of about the same size scale and, ideally, fully integrated with associated microelectronics, naturally they should capitalize on the same materials, processes, equipment, and technologies as those of the microelectronics industry. Because the process technology for silicon is already extensively developed for VLSI electronics, silicon is the dominant material for micromachining. Silicon is also mechanically superior to compound semiconductor materials and, by far, no other electronic material has been as thoroughly studied.
A wide array of micromachined silicon devices are fabricated using a high boron concentration "etch-stop" layer in combination with anisotropic wet etchants such as ethylenediamine and pyrocatechol aqueous solution (EDP), potassium hydroxide aqueous solution (KOH), or hydrazine (N2H2). Etch selectivity is defined as the preferential etching of one material faster than another and quantified as the ratio of the faster rate to the slower rate. Selectivity is realized for boron levels above 1019 cm−3, and improves as boron content increases.
It should be noted that etch stops are also used in bond and etch-back silicon on insulator (BESOI) processing for SOI microelectronics. The etch-stop requirements differ somewhat from those of micromachining, e.g., physical dimensions and defects, but the fundamentals are the same. Hence, learning and development in one area of application can and should be leveraged in the other. In particular, advances in relaxed SiGe alloys as substrates for high speed electronics suggests that a bond-and-etch scheme for creating SiGe-on-insulator would be a desirable process for creating high speed and wireless communications systems.

The Charles Stark Draper Laboratory, Inc.


A filament employing lawnmower blade apparatus includes a support disc which includes a central transverse lawnmower connection channel and a plurality of peripheral transverse fastener reception channels. A plurality of filament reception fasteners are provided each of which includes a fastener head, a filament reception channel located adjacent to the fastener head, a threaded shaft located adjacent to the fastener head, and a threaded nut screwed onto the shaft. A plurality of filaments are received in the respective filament reception channels of the filament reception fasteners. For each of the filament reception fasteners, the fastener head and the shaft are arrayed along a fastener longitudinal axis, and the filament reception channel extends perpendicular to the fastener longitudinal axis. Washers are located on the shafts of the filament reception fasteners between the nuts and the support disc. The filament reception channel includes exterior walls which are arrayed in a polygonal pattern. The fastener reception channel is also in a form of a polygonal pattern. The polygonal pattern of the exterior walls of each of the filament reception channels is a complementary pattern to the polygonal pattern of the fastener reception channels. The polygonal pattern of the exterior walls of the filament reception channel and the polygonal pattern of the fastener reception channel are in forms of a four-sided square.

1. Field of the Invention
The present invention relates generally to power lawnmowers and, more particularly, to power lawnmowers which employ cutting blades made of filaments.
3. Description of the Prior Art
The use of power lawnmowers that employ filaments for cutting blades is well known in the art. In this respect, throughout the years, a number of innovations have been developed relating to filament based cutting blades for lawnmowers, and the following U. S. patents are representative of some of those innovations: U.S. Pat. Nos. 4,112,653, 4,201,034, 4,726,176, 4,819,416, and 5,713,191. More specifically, U.S. Pat. No. 4,112,653 discloses a filament cutting blade for a lawnmower that is retained on a support disc by centrifugal force on the disc as the disc spins. Because the degree of centrifugal force varies with the rate of spin of the disc, it would be desirable if filaments were secured to a support disc in a manner which does not rely upon the use of centrifugal force on the disc.
U.S. Pat. No. 4,201,034 discloses a lawnmower that employs plural reels of filaments. Because of their complexity and their weight, it would be desirable if a lawnmower employed filaments without employing plural reels of filaments supported on a disc.
U.S. Pat. No. 4,726,176 discloses a lawnmower that has a disc that has horizontal grooves for receiving filaments. Once grooves are machined into a filament retaining disc, there is a substantial risk that the disc will be out of balance when it spins. Therefore, to avoid this risk, it would be desirable if a filament employing lawnmower were provided that does not employ a disc that has horizontal grooves machined into the disc for retaining the filaments.
U.S. Pat. No. 4,819,416 discloses a lawnmower that employs filaments attached to a disc that has pairs of adjacent vertical channels separated by a common wall. A filament is threaded in through one channel, around the common wall, and out through the second channel. With this device, two vertical channels are required for each filament that is employed. Also, the filament must be threaded into and out from the two vertical channels. To avoid the duplication, it would be desirable if a lawnmower that employs filaments were provided that does not employ two vertical channels for each filament that is employed. In addition, it would be desirable if a filament-employing lawnmower were provided that does not require a filament to be threaded into and out from a supporting disc.
U.S. Pat. No. 5,713,191, in a manner similar to above-mentioned U.S. Pat. No. 4,819,416, discloses a lawnmower disc that supports filaments by having the filaments threaded through pairs of adjacent vertical channels in the disc.
Still other features would be desirable in a filament employing lawnmower blade apparatus. For example, rather than having pairs of adjacent vertical channels for supporting a single filament in a disc, it would be desirable if a lawnmower disc had only one vertical disc channel for supporting each filament. In addition, rather than machining a lawnmower disc in a complex way to receive a filament, it would be desirable if the lawnmower disc were machined simply to receive a fastener, and the fastener is provided with a filament receiving channel.
Thus, while the foregoing body of prior art indicates it to be well known to use lawniowers that employ filaments for cutting blades, the prior art described above does not teach or suggest a filament employing lawnmower blade apparatus which has the following combination of desirable features: (1) has filaments secured to a support disc in a manner which does not rely upon the use of centrifugal force on the disc; (2) employs filaments without employing plural reels of filaments supported on a disc; (3) dies not employ a disc that has horizontal grooves machined into the disc for retaining the filaments; (4) does not employ two vertical channels for each filament that is employed; (5) does not require a filament to be threaded into and out from a supporting disc; (6) has only one vertical disc channel for supporting each filament; and (7) has a lawnmower disc that is machined simply to receive a fastener, and the fastener is provided with a filament receiving channel. The foregoing desired characteristics are provided by the unique filament employing lawnmower blade apparatus of the present 20 invention as will be made apparent from the following description thereof. Other advantages of the present invention over the prior art also will be rendered evident.

Filament employing lawnmower blade apparatus


A system for producing microbeads includes a microfluidic device defining a supply channel and a shearing channel, a microbead precursor material disposed in the supply channel, a carrier fluid disposed in the shearing channel, and a pressure distribution system fluidly connected to each of the supply channel and the shearing channel to control at least relative pressures of the microbead precursor material and the carrier fluid. The supply channel includes a check valve adapted to be subjected to a bias pressure that is sufficient to close the check valve to flow of microbead precursor material when a supply pressure of the microbead precursor material is below a threshold pressure and is open to flow of the microbead precursor material when the supply pressure of the microbead precursor material is greater than the threshold pressure. An end of the supply channel opens into the shearing channel such that the microbead precursor material is sheared into droplets by the carrier fluid flowing through the shearing channel. A pressure of the carrier fluid is less than the bias pressure. The microbead precursor material and the carrier fluid are substantially immiscible.

1. Field of Invention
The field of the currently claimed embodiments of this invention relates to systems and methods for high-throughput production of microbeads.
2. Discussion of Related Art
Microencapsulation is an attractive way to deliver cells and biologics into the human body, providing immunoisolation while allowing biomolecules, either preloaded or synthesized in situ by cells, to be released in a controlled manner. Typical microencapsulation involves injecting alginate from a syringe into a bath of calcium solution. While the generation process is rapid, the size distribution is extremely polydisperse. In addition, gel beads smaller than 300 microns cannot be routinely made, making injection through small bore catheters almost impossible. There remains a need for systems and methods to generate uniform microbeads that are small (<100 μm) at quantities that are suitable for clinical applications.
Reported microbead generation on microfluidic chips often involve fusion of manually-synchronized alginate and calcium droplets in oil, which severely limits the rate of bead generation (Zhao L B, Pan L, Zhang K, Guo SS, Liu W, Wang Y, et al. Generation of Janus alginate hydrogel particles with magnetic anisotropy for cell encapsulation. Lab Chip 2009 Oct. 21;9(20):2981-2986). Generation frequencies range from single hertz to a theoretical maximum of 4 kHz for inkjet-based techniques, although in practice Dohnai et al. only achieved 30 Hz (Dohnal J, Stepánek F. Inkjet fabrication and characterization of calcium alginate microcapsules. Powder Technology;200(3):254-259). Centrifugation-based generation results in comparable frequency to our method at 600 Hz, but can only prepare beads with diameters of hundreds of microns (Haeberle S, Naegele L, Burger R, von Stetten F, Zengerle R, Ducree J. Alginate bead fabrication and encapsulation of living cells under centrifugally induced artificial gravity conditions. J Microencapsul 2008 Jun.;25(4):267-274). On the other hand, a recent report used oleic acid to act as both continuous phase (with alginate as the discrete phase) and calcium reservoir (Kim C, Lee K S, Kim Y E, Lee K J, Lee S H, Kim TS, et al. Rapid exchange of oil-phase in microencapsulation chip to enhance cell viability. Lab Chip 2009 May 7;9(9):1294-1297). Although it solved the problem of synchronizing the different aqueous inlets, clogging at the droplet generation nozzle was a significant problem, especially at higher generation frequencies, where a delicate balance of flow pressures must be maintained.
Another challenge in high frequency generation is bead aggregation, since only partial crosslinking occurs at high generation frequency due to relatively low saturation concentration of calcium ions in the oil phase. There thus remains a need for improved systems and methods for producing microbeads.

Systems and methods for high-throughput microfluidic bead production


According to one embodiment, a storage device comprises a nonvolatile memory and a memory controller that performs reading and writing data from and into the nonvolatile memory. A number, not being 2n, of threshold areas can be set in the memory cells of the nonvolatile memory. The memory controller performs first writing based on first data value assignment, which sets 2n data values to correspond to 2n threshold areas, in first-time writing into a first memory cell of the nonvolatile memory and performs second writing on the first memory cell after the first writing without erasing data based on second data value assignment, which sets 2n data values to correspond to 2n threshold areas including threshold areas not used in the first data value assignment.

In a NAND flash memory (hereinafter referred to as a NAND memory), information is stored by means of the amounts of charge retained in the floating gates of memory cells. The threshold voltage is determined according to the amount of charge retained in the floating gate of the memory cell. The threshold voltage refers to a voltage at which the transistor of the memory cell becomes ON (current starts flowing). That is, when a voltage higher than or equal to the threshold voltage is applied to the memory cell, current flows, and when a voltage lower than the threshold voltage is applied, current does not flow. In the NAND memory, a plurality of threshold voltage ranges (areas) are defined with one data value being assigned to each area, and electrons are injected so that the threshold voltage of the memory cell is within the area corresponding to one of the data values. By this means, each memory cell can store a data value.
In conventional NAND memories, the number of threshold voltage areas of the memory cell that are distinguishable is a power of two. Hence, increasing the number of data values storable per memory cell from that of a memory cell capable of, e.g., three-bit storage per memory cell results in the use of a memory cell capable of four-bit storage. In this case, the number of areas increases greatly from 8 to 16.

Storage device, memory controller and memory control method


A method of connecting a first computing device and a wireless access point over a first wireless network using a second computing device, where the first and second computing devices are both enabled to communicate over the first wireless network and are both enabled to communicate over a second, different wireless network, and where there are first wireless network connection credentials for the wireless access point. The method includes establishing a wireless connection between the first and second computing devices over the second wireless network, sending the first wireless network connection credentials for the wireless access point from the second computing device to the first computing device over the second wireless network, and then establishing a connection between the first computing device and the wireless access point on the first network using the first wireless network connection credentials for the wireless access point.

This disclosure relates to interconnecting computer devices over wireless networks.
Computing devices can be connected over wireless networks, for example over WiFi. In order to connect, the devices need the network credentials, which often include the network name (SSID), password, network key, or any secret that authenticates a new network node. This interconnection process can be relatively complex, requiring user intervention. It can also involve a user opening multiple menus or applications on a device, which can be difficult and confusing.
As one non-limiting example, when a mobile computing device such as a smartphone or tablet is used to setup a wireless speaker package, a setup application for the wireless speaker package may be downloaded onto the device. Ultimately what is needed (or at least desirable in some circumstances) is for the device and the wireless speaker package to communicate over an available WiFi network. Some mobile computing devices, such as those running iOS®, do not allow an app to modify a WiFi setting in the device. In these cases, the user must enter the WiFi network credentials in the settings menu of the device, and then use the app to setup and connect the wireless speaker package. This process is cumbersome and can lead to difficulties in the wireless speaker package setup process.


A fluid separation module is provided. The module comprises a monolithic core having a first set of passages extending from a feed end to a retentate end. The first set of passages has a specific cross-sectional area. A second set of passages are positioned in a non-parallel relationship to the first set of passages for passage of a permeate. Additionally, the fluid separation module has at least one transducer affixed to the monolithic core. The fluid separation module of the present invention may be used for macrofiltration, microfiltration, ultrafiltration, nanofiltration, and reverse osmosis.

Filtration devices have been used in the past for the separation of components of a fluid based on the size, shape or physical character of the components and by employing hydraulic pressure. One component of the fluid (permeate or filtrate) is selectively forced through a membrane to separate that component from the remainder of the mixture. In straight-through filtration, the fluid is passed through a filter and suspended matter remains on the filter surface or within the filter matrix allowing only the filtrate to pass through. Cross-flow filtration allows for tangential flow across the filter surface to sweep away suspended matter which is unable to pass through the filter surface pores.
Ultrafiltration is typically carried out using a cross-flow filtration technique which involves a porous substrate. During cross-flow filtration, the feed flows parallel to the membrane and the permeate flows perpendicular to the membrane. One way in which this is achieved is by using a porous ceramic tube which is multi-channeled and has a high surface area for filtration. Such devices usually employ filtrate conduits to carry the filtrate to a filtrate collection zone. However, many of these configurations are bulky, and often require extensive and complicated piping arrangements.
Hoover et al. (U.S. Pat. No. 4,069,157) provided a ceramic support having a multiplicity of parallel passageways therethrough. The passageways were coated with an ultrafiltration membrane. The support had a specific surface area to volume ratio of about from 300 to 2000 m .sup.2 /m.sup.3 (3 to 20 cm .sup.2 /cm.sup.3) and a defined permeability factor which is greater than about 1.0.times.10.sup.-4 m. The general configuration of the support element is an elongated form having a constant cross-sectional shape along its length.
The passageways can be of any shape convenient for the methods of preparation and membrane insertion and the channels generally have a total cross-sectional area which comprises from about 40 to 75% of the total cross-sectional area of the element. This system requires that pressure be controlled according to the discharge of the concentrated feed stock through a valve, the flow of fresh feed stock through a pump and the flux of filtrate from an element.
Goldsmith (U.S. Pat. No. 4,781,831) disclosed a cross-flow filtration device which includes a structure of porous material which defines a plurality of passage-ways extending longitudinally from the feed end of the structure to the retentate end. A number of filtrate conduits are within the structure for carrying the filtrate from within the structure toward a filtrate collection zone. The filtrate conduits provide paths of lower flow resistance than that of alternative flow paths through the porous material. The structure is constructed such that the filtrate conduits are distributed among the passageways to provide low pressure drop flow paths for the filtrate flow from the passageways through the porous material to nearby filtrate conduits.
Thompson (U.S. Pat. No. 4,253,962) discloses a non-destructive ultrasonic vibratory system for removing the fouling layer which forms on the filter surface and reduces the filtering efficiency with use. Also disclosed is the introduction of a frequency sweep to avoid formation of sustained standing waves which are deleterious to the filter membrane.
An object of the present invention is to provide a fluid separation module which acts as a cross-flow filter capable of extracting the retentate from one portion of the module and continuously extracting the permeate (filtrate) from another portion of the module.
Another object of the present invention is to provide a fluid separation module which has a high volume specific surface area ranging from about 2 to 20 cm.sup.2 /cm.sup.3.
Another object of the present invention is to provide a fluid separation module which optimizes the transmembrane pressure such that it is uniform from the feed inlet to the retentate outlet.
Another object of the present invention is to provide a fluid separation module which is easy to fabricate and low in manufacturing cost.
Another object of the present invention is to provide a process for fluid separation which utilizes the fluid separation module.
Another object of the present invention is to provide a process which uses ultrasonic vibration to remove fouling of the passages.

Fluid separation module having a porous monolithic core


The present invention relates to a new tumor suppressor, designated Killin. Also described are diagnostic and therapeutic uses of the Killin protein and the killin gene, alone or in combination with traditional cancer therapies.

I. Field of the Invention
The present invention relates to the fields of oncology, genetics and molecular biology. More particular the invention relates to the identification, on human chromosome 10, of a p53-related tumor suppressor gene designated as Killin.
II. Related Art
Oncogenesis is a multistep biological process, which is presently known to occur by the accumulation of genetic damage. On a molecular level, the process of tumorigenesis involves the disruption of both positive and negative regulatory effectors (Weinberg, 1989). The molecular basis for human colon carcinomas has been postulated, by Vogelstein and coworkers (1990), to involve a number of oncogenes, tumor suppressor genes and repair genes. Similarly, defects leading to the development of retinoblastoma have been linked to another tumor suppressor gene (Lee et al., 1987). Still other oncogenes and tumor suppressors have been identified in a variety of other malignancies. Unfortunately, there remains an inadequate number of treatable cancers, and the effects of cancer are catastrophic—over half a million deaths per year in the United States alone.
p53 is the most frequently mutated, disrupted, and/or allelically lost tumor suppressor gene in human cancer, and it has been a focal point for intensive cancer research (Levine, 1997; Vogelstein et al., 2000; Vousden and Prives, 2005). Functionally, p53 works as a sequence dependent transcription factor, which upon activation by genotoxic stresses such as DNA damages regulates the expression of a set of target genes that are involved in cell growth control and apoptosis (El-Deiry, 1998; Yu et al., 1999; Vousden and Lu, 2002; Liang and Pardee, 2003). In contrast to a large number of p53 target genes that were implicated in cell apoptosis, activation of cell cycle arrest at G1 by p53 results predominantly from the induction of p21 (Deng et al., 1995), whereas p21 as well as GADD45 and 14-3-3 proteins were also shown to be involved in G2-M arrest (Taylor and Stark, 2001). Among the known p53 target genes implicated in apoptosis, a family of Bcl-2 related genes, such as bax, puma and noxa, are the best characterized and thought to work through a mitochondria-dependent death pathway (Yu and Zhang, 2005).
Through a genetic approach using somatic gene knockout strategy, it was shown that cellular choice between growth arrest and death upon p53 activation appears to depend on at least two factors. For cell types that undergo p53-mediated G1 arrest, elimination of p21 sensitizes cells to die (Polyak et al., 1996; Yu et al., 2003). In such cases, p21 clearly plays a protective role in apoptosis. In cell types that are prone to apoptosis upon p53 activation, transacting death-inducing factors are dominant over p21-mediated protection (Polyak et al., 1996; Yu et al., 2003). In the case of p21-mediated G1 arrest which protects cells from p53 induced apoptosis, one possible explanation could be that the apoptosis initiating event(s) require cells to enter S-phase. Supporting evidence for such S-phase-coupled apoptosis include findings that forced S-phase entry by unrestricted E2F activity can trigger the activation of caspases and apoptosis (Nahle et al., 2002; Gottifredi and Prives, 2005). Conceivably, DNA damage can happen to cells at any phase during the cell cycle. The induction of either p21 in cells at G1, or p21, GADD45 and 14-3-3 at G2/M phase by p53 will lead to growth arrest at the respective cell cycle phases. However, little is known about p53-mediated checkpoint control during S-phase where cells would run the highest risk of incorporating mutations after sustained DNA damage. It is logical that apoptosis would be the best choice for eliminating these cells. summary of the invention


Adaptive streaming is rendered more efficiently combinable with the usage of an open GOP structure by configuring a device for retrieving a video such that the same schedules a transition phase before switching from a first video stream to the second video stream, and/or by configuring a device for outputting a video in accordance with the adaptive streaming protocol such that the same supports switching outputting the video in form of a layered video stream or an increased spatial resolution stream. A media scene composed of several channels is made more efficiently streamable spending, for each channel, a set of representations of the respective channel which differ in a temporal distribution of random access points. By this measure, a client device may schedule the switching between the representations for optimizing fast tune-in and low bitrate variations.

Using adaptive streaming, a media data stream is provided from server to client in temporal segments. Depending on the application, the server may offer to the client a media at different bit rates. That is, sequences of temporal segments for different versions of the media content are available to the client for download and, during media streaming, a switching between the different versions is feasible. Accordingly, the sequence of temporal segments retrieved by the client from the server comprises, in an interleaved manner, ones stemming from a first version and ones stemming from another version. Problems may occur, however, if one would like to take advantage of the more efficient open GOP structure for encoding the media content as, in this case, reference pictures, in particular the leading pictures that miss references when decoding the stream is started at their associated random access point (e.g. random access skip leading pictures—RASL pictures in HEVC), may get lost in such situations. Using a closed GOP structure for coding the media content does not cause these problems, but ends up into a lower coding/compression efficiency.
Other aspects for which there is a general interest in achieving improvements in adaptive streaming, pertain streaming parameters such as the frequency of requests from the client to the server for requesting the issuance of a next temporal segment, a mean tune-in latency, i.e., the mean time at which a client is enabled to gain access to a certain media content, which latency should be minimalized, and an avoidance for bit rate peaks as such bit rate peaks in streaming media content involves a larger input buffer at the client for compensating the bit rate variations.

Fraunhofer-Gesellschaft zur Foerderung der angewandten Forschung e.V.


A wrenching member includes at least two spaced-apart and substantially oppositely facing drive surfaces, each of which has a roughened region and an unroughened region thereon, with the roughened region being disposed adjacent to one end of one of the drive surfaces and adjacent to the other end of the other drive surface so as to afford a differential driving arrangement which exerts a greater frictional wrenching force in one direction than in the opposite direction.

1. Field of the Invention
This invention relates generally to drive surface configurations of the type which are commonly used with driving elements, such as wrenching members.
2. Description of the Prior Art
There are many types of known drive elements for driving associated fasteners or other driven members. For example, one common type of drive element is a wrench, which may have a handle, with a wrenching head at either or both ends. Another common type of drive element is a socket tool for use with associated handle or lever members. Each such drive element typically has at least two drive surfaces which are dimensioned and arranged for engagement, respectively, with corresponding flat sides of an associated fastener or other driven member of appropriate size. The driving surfaces are commonly smooth planar surfaces.
A disadvantage of such a driving element is the inadequate gripping force between the driving surfaces and the associated driven member. As a result, the driving element may have a tendency to slip off the driven member when torque is applied thereto. Also, it increases stress in the associated driven member and can tend to deform the corners thereof. This tendency to round off the corners of a fastener or other driven member is particularly likely to occur in the off or counterclockwise direction of rotation, since it frequently requires more torque to loosen a tightened fastener, for example, then it does to tighten it.
Heretofore, driving elements have been provided with roughened or high-friction regions on the driving surfaces to improve gripping engagement with the associated driven member. Thus, for example, serrations may be provided along each driving surface. While such serrations can improve overall frictional gripping, they have heretofore provided essentially the same frictional gripping force in either direction of rotation.

Drive configuration with differential driving surfaces


An attachment 52 comprises: a carriage connecting section 74 connected to a carriage 12 of an embroidery frame transfer device 4; and a metal fastener fixed to an attaching block 32 at the right-hand end portion of the carriage connecting section 74 and having a connecting section of a nonstandard embroidery frame 51 connected thereto. By connecting a connecting section 66 of the nonstandard embroidery frame 51 to the metal fastener 75 of the attachment 52 and by connecting the carriage connecting section 74 of the attachment 52 to the carriage 12, the nonstandard embroidery frame 51 can be mounted indirectly on the carriage 12. Thus, the nonstandard embroidery frame 51 of the type different in construction for attachment to the carriage 12 can be connected to the carriage 12.

Generally, the embroidery frame transfer device is provided with: an embroidery frame for holding a cloth to be embroidered; a carriage capable of mounting/demounting the embroidery frame; a Y-direction transfer mechanism for moving the carriage in the widthwise direction (or Y-direction) of a machine head portion; and an X-direction transfer mechanism for moving the carriage together with the Y-direction transfer mechanism in the longitudinal direction (or X-direction) of the machine head portion. By executing the sewing actions while moving the embroidery frame in the X- and Y-directions by the embroidery frame transfer device, an embroidery pattern is formed on the cloth.
In this case, various sizes and shapes are provided for the embroidery frame so that the user mounts an embroidery frame of a suitable kind according to the size, shape or the like of the cloth or the embroidery pattern to the carriage.

Embroidery frame transfer device and attachment


In a method for shape grinding a circumferential edge of a spectacle lens, and optionally subsequently facet grinding, in a lens grinding machine that comprises a lens securing shaft and a grinding wheel moveable in a controlled manner relative to the lens securing shaft, the grinding pressure is increased for a decreasing radius of the spectacle lens measured from the rotational axis of a lens securing shaft to a respective contacting location of the spectacle lens at the grinding wheel. The spectacle lens grinding machine for performing the method includes a machine frame, a lens securing shaft and a grinding wheel rotatably supported in the machine frame, a control motor connected to the machine frame for advancing the grinding wheel toward the lens securing shaft, and a computer for controlling the control motor. A travel sensor for detecting the advancing stroke of the grinding wheel toward the lens securing shaft is provided. The travel sensor includes a data transmitting line to the computer. The grinding pressure is computer-controlled based on the radius at the contacting location at the grinding wheel and data transmitted by the travel sensor. The grinding pressure is changed by changing the torque of the control motor.

The invention relates to a method and a spectacle lens grinding machine for shape grinding the circumferential edge of spectacle lenses and optionally for subsequently grinding a facet with a spectacle lens grinding machine comprising a spectacle lens securing shaft for securing the spectacle lens and a grinding wheel that is controllably moveable relative to the lens securing shaft.
In order to perform the shape grinding of the circumferential edge of spectacle lenses and the subsequent facet grinding as fast as possible, the grinding pressure for a rpm of the grinding wheel selected as high as possible is adjusted to a value which allows grinding the desired shape of a spectacle lens starting from a circular lens blank into without damaging or even destroying the spectacle lens.
For a fixedly adjusted grinding pressure it may occur that the torque acting during grinding onto the spectacle lens blank is greater than the securing force for clamping the lens blank at the securing shaft so that the spectacle lens blank may be rotated relative to the securing shaft. Such a rotation, when a spherical spectacle lens without reading glass portion is ground, is of minimal impact when no displacement of the focal point of the lens blank from the axis of rotation of the securing shaft occurs; however, such a rotation should not occur at all when the lens blank has a precisely angularly arranged reading glass portion relative to the optical axis of the lens blank or is to be provided with a cylindrical or prismatic ground portion whose axis position relative to the arrangement of the spectacle lens within the spectacle frame is predetermined.
A rotation of the spectacle lens blank within the securing shaft can occur especially when spectacle lenses with a highly anti-reflective coating are machined because these lenses have an especially low frictional coefficient relative to the securing devices at the securing shaft or attached holding blocks or suction devices.
When the grinding pressure is decreased to such an extent that a rotation of the lens blank on the securing shaft can be prevented with certainty, the machining time of the lens blank will increase and the output of the spectacle lens grinding machine is thus reduced. A change of the grinding pressure as a function of the width of the edge of the spectacle lens such that the grinding pressure is increased when the width of the lens blank is greater and is lowered when the width of the lens blank is smaller, is known from European Patent Application 0 096 337. However, this type of controlling of the grinding pressure leads to the grinding pressure being greatest for myopic lenses when the radius of the spectacle lens is greatest and to grinding pressure becoming smaller and smaller with decreasing radius of the spectacle lens, while this known control for hyperopic lenses has the opposite effect. With this kind of control and the grinding pressure a slipping of the spectacle lens of the securing shaft due to the grinding pressure can only be avoided when for myopic lenses the grinding pressure at the greatest radius of the spectacle lens is adjusted to a value that prevents slipping which means that with a radius that decreases the grinding pressure is to be decreased also so that overall the machining time is increased. This disadvantage does not occur for grinding of hyperopic lenses; however, the grinding pressure controlled based on the width of the spectacle lens is not always optimized.
It is therefore an object of the present invention to provide a method and a spectacle lens grinding machine for shape grinding the circumferential edge of spectacle lenses and for an optional subsequent facet grinding step with which a slipping of the spectacle lens secured on the securing shaft can be reliably prevented and with which the grinding of the circumferential edge of the spectacle lens can be performed as quickly as possible without running the risk of breaking or damaging the spectacle lens.

Method and spectacle lens grinding machine for shape grinding the circumferential edge of spectacle lenses and optionally for subsequently grinding a facet


The invention relates to a valve-controlled positive displacement pump having valve triggering, which permits the forced opening or keeping open of an inlet valve, operating in the manner of a non-return valve, of a displacer working space, so that the displacer working space remains connected to the inlet side of the unit even during the working stroke of the displacer, and the assigned displacer is not able to work efficiently. The design according to the invention is particularly suitable for radial piston pumps.

The invention relates to a valve-controlled positive displacement pump having valve triggering, which permits the positive opening or keeping open of an inlet valve, operating in the manner of a non-return valve, of a displacer working space, so that the displacer working space can be connected to the inlet side of the unit even during the working stroke of the displacer and can be shut off from the outlet side of the unit by its outlet valve, which remains closed when the inlet valve is open.
German Patent Document DOS 3,028,396 discloses an appropriate piston pump having piston working spaces arranged in series. Special fluid members can be used forcibly to lift the suction valves out of their closed position or to prevent them from reaching the closed position. As a result, the respective pistons are prevented from doing effective pumping, because it is not possible to build up an effective pressure in the piston working spaces.
The delivery rate of the pump can be matched very quickly to the respective requirements by means of the suction valve triggering, without the need to shut down the pump or its drive.
Again, there are in principle other possibilities for quickly shutting down the delivery flow of a piston pump.
For example, a pump can work, if necessary, in so-called circulating operation, in which it is achieved by appropriate control of a reversing valve that the medium delivered by the pump flows back by a short path to the suction side or to a reservoir arranged on the suction side, and is not fed to the respective load on the pressure side of the pump. A corresponding arrangement is represented with reference to a radial piston pump in German Patent Document DOS 2,425,022. In this case, the reversing valve is controlled as a function of the pressure applied to the load, it being the case that upon the reaching of a first pressure threshold value initially only a restriction of the flow on the suction side of the pump is formed, in order in this way to reduce the delivery rate of the pump. As soon as a second pressure threshold value is then reached on the pressure side of the pump, a switch is made to circulating operation, so that the pump no longer works effectively.
It is known from British Patent Document 1,413,998 to provide two piston working spaces whose pistons work in anti-phase with a connecting line which can be shut off. The pump works in the normal way in the closed state of this connecting line. As soon as the connecting line is opened and a flow is enabled in both directions, the pumping medium is shifted back and forth continuously between the two piston working spaces, because the pressure stroke of the piston in one piston working space coincides with the suction stroke of the piston in the other piston working space. Consequently, the pumping medium displaced from the one piston working space is received by the other piston working space. In this way, the pump is prevented from working effectively.
If necessary, it can be provided in accordance with British Patent Document 1,413,998 to arrange a non-return valve in the connecting line, so that after opening of the connecting line only a flow in one direction is enabled. The consequence of this is that during the pressure stroke of the piston in one piston working space the pumping medium can be shifted from this piston working space into the other piston working space, whose piston is executing a suction stroke. As soon thereafter as the direction of movement of the piston is reversed, the medium displaced by the other piston, which is now in the pressure stroke, cannot flow back through the connecting line--it is, rather, expelled to the pressure side of the pump by the pressure valve assigned to the other piston. In this way, the working of only one piston is rendered virtually ineffective, that is to say the delivery rate of the pump is halved.
A stepped control of the pump can also be undertaken in this way. The first step is, for the purpose of reducing the pumping capacity, to release only one connecting line having a non-return valve in order to reduce the delivery rate of the pump. Thereafter, a connecting line which allows flow in both directions can then be released in order to switch the pump to become ineffective.
U.S. Pat. No. 3,682,565 shows a radial piston pump whose pistons are loaded by means of springs against an eccentric which drives the pistons and whose circumference interacts with the facing end faces of the pistons. The piston working spaces each have a pressure valve which is arranged on the pump housing coaxially with the respective piston and whose valve body controls a bore coaxial with the piston. The suction valves are arranged in each case on the piston side, the suction valve body in the associated piston controlling an axial bore which communicates via radial bores in the piston with the eccentric working space, which forms the suction side of the pump or is connected thereto. Arranged on the pressure side of the pressure valves are relief valves which in normal operation connect the outlet side of the pressure valves to the pressure side of the pump or to the load connected there. As soon as a pressure threshold value is reached, the respective relief valve reverses, the outlet side of the pressure valve of the respectively assigned piston working space being connected to the suction side and simultaneously shut off from the pressure side of the pump or from the load connected there.
It is achieved in this way that individual pistons or all the pistons of the pump are unable to deliver any pumping medium to the pressure side or to the load a soon as the pressure threshold value is reached.
German Patent Document DOS 3,740,672 discloses a valve-controlled piston pump in which the piston working spaces are assigned in each case a separate outlet valve upon the opening of which the piston working space is connected to the suction side of the pump. Consequently, a similar effect is achieved as in the case of suction valve triggering.
For the rest, reference is made to the technological background to be seen in German Patent Documents DOS 3,240,405; DOS 3,504,163; and DOS 1,653,632.
It is an object of the invention to provide a positive displacement pump equipped with valve triggering, whose design is also well suited for realizing a radial piston pump having triggering of the inlet valve, that is to say having suction valve triggering.
This object is achieved according to preferred embodiments of the invention by providing an arrangement comprising a:
valve-controlled positive displacement fluid device arrangement having valve triggering, which permits the forced opening or keeping open of an inlet valve, operating in the manner of a non-return valve, of a displacer working space, so that the displacer working space can be connected to the inlet side of the unit even during the working stroke of the displacer and can be shut off from the outlet side of the unit by its outlet valve, which remains closed when the inlet valve is open,
wherein the displacer includes a piston which is spring-loaded against an eccentric which drives it,
wherein the associated inlet valve is arranged on the piston and controls by means of its valve body an inlet opening penetrating the piston from a space on the inlet side to the piston working space,
wherein the eccentric or a sleeve-like part arranged on its circumference is axially displaceable, and
wherein arranged on the circumference of the eccentric or of the sleeve-like part are axially adjacent regions whose otherwise identical cross-sections have different diameters, it being the case that in one axial position of the circumference the region having the larger diameter keeps the inlet valve body away from its closed position in the manner of a stop, whereas the other region having the smaller diameter becomes effective in another axial position of the circumference and permits closure of the inlet valve body.
The invention is based on the general idea of controlling the mobility of the inlet valve body by elements on the eccentric side which, for their part, can be switched to become effective or ineffective by axial displacement in the direction of the axis of rotation of the eccentric.
It is advantageous in this case that the invention can be directly realized with radial piston pumps, because essential parts of conventional radial piston pumps can be taken over virtually unchanged. Consequently, the invention is explained below principally with reference to pumps.
Nevertheless, the invention is not restricted to pumps. Rather, preferred embodiments of the invention can also advantageously be used with hydraulic motors and serve there to vary the motor displacement.
In order to apply the invention in the above-mentioned radial piston pumps, it is essentially sufficient to construct the suction valve such that the suction valve body can interact with the above-mentioned regions on the circumference of the eccentric or of the sleeve-shaped part.
According to a preferred embodiment, it can be provided for this purpose that there is arranged on the suction valve body an extension or stem which is directed against the eccentric and which interacts with the regions of different cross-section on the circumference of the eccentric or of the sleeve-shaped part in such a way that the suction valve is able to close when the region of smaller cross-section is pushed into the zone of movement of the extension or stem, while the extension or stem bears against the region of larger cross-section before the closing position of the suction valve body is reached when the eccentric or the sleeve-shaped part is correspondingly axially displaced.
In a particularly preferred embodiment, it is possible to arrange on the circumference of the axially displaceable eccentric or of the axially displaceable sleeve-shaped part a circumferential groove, which can be relatively displaced by displacing the eccentric or the sleeve-shaped part into the region of movement of the extension or stem, and thus enable closure of the suction valve body.
In this embodiment, the circumferential regions of the eccentric or of the sleeve-shaped part, which axially adjoin the circumferential groove, can serve in all axial positions of the eccentric or of the sleeve-shaped part to guide and to drive the pump piston or the pump pistons and moreover, given appropriate displacement of the eccentric or of the sleeve-shaped part, take over the function of a stop, interacting with the extension or stem of the suction valve body, in order to prevent the suction valve body from assuming its closing position.
The above-noted circumferential groove is likewise able to take over a double function by, on the one hand, permitting closure of the suction valve body in the corresponding axial position of the eccentric or of the sleeve-shaped part and, on the other hand, producing between the eccentric or sleeve-shaped part and the eccentric-side end face of the piston in this operating state, a channel suitable for the passage of pumping medium which communicates with a suction opening in the piston or piston cap that is controlled by the suction valve body.
Embodiments are contemplated with construction of the piston-side opening controlled by the suction valve body as an axial bore of the piston and connecting it to the eccentric working space, which is constructed as the suction side of the pump or is connected to a suction port of the pump, without appreciable restriction.
The same basically applies when instead of the circumferential groove a circumferential stage or protrusion is arranged on the circumference of the eccentric or of the sleeve-shaped part, so that a region of the eccentric or of the sleeve-shaped part of small cross-section is formed on the one side of the circumferential stage, and a region of larger cross-section is formed on the other side.
One side wall or both side walls of the circumferential groove can also be constructed as a cone. Again, a conical region can be provided instead of a circumferential stage having a steep transition between the regions of different cross-section. It is possible in this way in the case of axial displacement of the eccentric or of the sleeve-shaped part to open a previously closed suction valve relatively slowly by virtue of the fact that the extension or stem of the suction valve body slides onto the conical region during axial displacement of the eccentric or of the sleeve-shaped part.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.

Valve-controlled displacer unit having valve triggering


By appropriately orienting the channel length direction with respect to the crystallographic characteristics of the silicon layer, the stress-inducing effects of strained silicon/carbon material may be significantly enhanced compared to conventional techniques. In one illustrative embodiment, the channel may be oriented along the <100> direction for a (100) surface orientation, thereby providing an electron mobility increase of approximately a factor of four.

1. Field of the Invention
Generally, the present invention relates to the formation of integrated circuits, and, more particularly, to the formation of transistors having strained channel regions by using strain-inducing sources, such as an embedded strained layer, in the drain and source regions to enhance charge carrier mobility in the channel region of a MOS transistor.
2. Description of the Related Art
The fabrication of integrated circuits requires the formation of a large number of circuit elements on a given chip area according to a specified circuit layout. Generally, a plurality of process technologies are currently practiced, wherein, for complex circuitry, such as microprocessors, storage chips and the like, CMOS technology is currently one of the most promising approaches, due to the superior characteristics in view of operating speed and/or power consumption and/or cost efficiency. During the fabrication of complex integrated circuits using CMOS technology, millions of transistors, i.e., N-channel transistors and P-channel transistors, are formed on a substrate including a crystalline semiconductor layer. A MOS transistor, irrespective of whether an N-channel transistor or a P-channel transistor is considered, comprises so-called PN junctions that are formed by an interface of highly doped drain and source regions with an inversely doped channel region disposed between the drain region and the source region.
The conductivity of the channel region, i.e., the drive current capability of the conductive channel, is controlled by a gate electrode formed near the channel region and separated therefrom by a thin insulating layer. The conductivity of the channel region, upon formation of a conductive channel due to the application of an appropriate control voltage to the gate electrode, depends on the dopant concentration, the mobility of the majority charge carriers, and, for a given extension of the channel region in the transistor width direction, on the distance between the source and drain regions, which is also referred to as channel length. Hence, in combination with the capability of rapidly creating a conductive channel below the insulating layer upon application of the control voltage to the gate electrode, the overall conductivity of the channel region substantially determines the performance of the MOS transistors. Thus, the reduction of the channel length, and associated therewith the reduction of the channel resistivity, renders the channel length a dominant design criterion for accomplishing an increase in the operating speed of the integrated circuits.
The continuing shrinkage of the transistor dimensions, however, involves a plurality of issues associated therewith, such as reduced controllability of the channel, also referred to as short channel effects, and the like, that have to be addressed so as to not unduly offset the advantages obtained by steadily decreasing the channel length of MOS transistors. Since the continuous size reduction of the critical dimensions, i.e., the gate length of the transistors, necessitates the adaptation and possibly the new development of highly complex process techniques, for example, for compensating for short channel effects, it has been proposed to also enhance the channel conductivity of the transistor elements by increasing the charge carrier mobility in the channel region for a given channel length, thereby offering the potential for achieving a performance improvement that is comparable with the advance to a future technology node while avoiding or at least postponing many of the problems encountered with the process adaptations associated with device scaling.
One efficient mechanism for increasing the charge carrier mobility is the modification of the lattice structure in the channel region, for instance by creating tensile or compressive stress in the vicinity of the channel region so as to produce a corresponding strain in the channel region, which results in a modified mobility for electrons and holes, respectively. For example, compressive strain in the channel region may increase the mobility of holes, thereby providing the potential for enhancing the performance of P-type transistors. On the other hand, the creation of tensile strain in the channel region of an N-channel transistor may increase electron mobility. The introduction of stress or strain engineering into integrated circuit fabrication is an extremely promising approach for further device generations, since, for example, strained silicon may be considered as a "new" type of semiconductor material, which may enable the fabrication of fast powerful semiconductor devices without requiring expensive semiconductor materials, while many of the well-established manufacturing techniques may still be used.
Therefore, in some approaches, the hole mobility of PMOS transistors is enhanced by forming a strained silicon/germanium layer in the drain and source regions of the transistors, wherein the compressively strained drain and source regions create strain in the adjacent silicon channel region. To this end, the drain and source extension regions of the PMOS transistors are formed on the basis of ion implantation. Thereafter, respective sidewall spacers are formed at the gate electrode as required for the definition of the deep drain and source junctions and the metal silicide in a later manufacturing stage. Prior to the formation of the deep drain and source junctions, these regions are selectively recessed based on the sidewall spacers, while the NMOS transistors are masked. Subsequently, a highly in situ doped silicon/germanium layer is selectively formed in the PMOS transistor by epitaxial growth techniques. Since the natural lattice spacing of silicon/germanium is greater than that of silicon, the epitaxially grown silicon/germanium layer, adopting the lattice spacing of the silicon, is grown under compressive strain, which is efficiently transferred to the channel region, thereby compressively straining the silicon therein. This integration scenario results in a significant performance gain of the P-channel transistors. Hence, a similar concept has been proposed for N-channel transistors by using a silicon/carbon material that has a smaller lattice spacing compared to silicon. The resulting gain in performance, however, is less pronounced than expected. Since the further device scaling may involve further performance reducing mechanisms for countering short channel effects, such as increased dopant levels in the channel region, high-k dielectrics in the gate insulation layer and the like, it is, however, of high importance to provide efficient techniques for compensating or over-compensating for such mobility-degrading approaches by efficiently increasing the charge carrier mobility for N-channel transistors by using strain-inducing mechanisms, such as strained silicon/carbon material and the like.
The present invention is directed to various methods and systems that may solve, or at least reduce, some or all of the aforementioned problems.

Transistor having a channel with tensile strain and oriented along a crystallographic orientation with increased charge carrier mobility


The present invention relates to a method for detecting anomalies in an infrastructure comprising the step of analyzing each of the data packets (PD) exchanged in the telecommunication system; identifying for each of the analysed data packets (PD) all the network protocols used and at least one field of each of the protocols; generating a virtual representation of the infrastructure (1) for each of the exchanged data packets (PD) and on the basis of the identified protocols and fields; storing the virtual representation generated for each of the exchanged data packets (PD); comparing the virtual representation stored with at least one comparison element, identifying at least one critical state of the infrastructure from the differences and/or similarities between the stored virtual representation and the comparison elements; signaling, by means of the computerized data processing means, an anomaly of the infrastructure when at least one of the critical states is identified in the virtual representation.

Industrial systems are defined by physical infrastructures provided with subsystems and components capable of physically interact with each other to obtain the functionalities required by the same industrial systems.
Systems of the aforesaid type are, for example, industrial systems for the manufacturing production, industrial systems for the generation of energy, infrastructures for the distribution of fluids (water, oil and gas), infrastructures for the generation and/or transmission of electric power and infrastructures for transport management.
The logical connection of the industrial system, or of the subsystems and components thereof, allows to obtain a so-called industrial automation system, wherein the control can be operated in correspondence of the subsystem or component to be controlled or rather remotely, i.e. at a distance within the area occupied by the system or even outside the same area.
The definition of an industrial automation system of the aforesaid type for a physical infrastructure exposes the same huge security problems, since the control of the industrial system can be susceptible to criminal activities. To protect the infrastructure, or the automation system that controls it, the so-called distributed control systems or SCADA are known in the field of automatic control. The acronym SCADA (Supervisory Control and Data Acquisition) is precisely related to a distributed system for the monitoring and supervision of physical systems, such as the aforementioned infrastructures or their subsets and components, provided with RTUs (Remote Terminal Units) allowing the interface of the aforesaid physical systems to the distributed control system or SCADA. The RTU monitors the digital and analogue field parameters and transmits the data to the central monitoring station, possibly with the possibility of piloting the physical systems, thus allowing the SCADA-type systems the supervision, control or remote control to limit the possibility of intrusion into the automation system of the infrastructure itself. Furthermore, SCADA-type systems allow monitoring the management of the anomalies of an infrastructure, by the logic control of its subsets and components.
A typical approach of the SCADA system involves the use of the "pull" model, wherein each RTU is configured with a remote access number and the SCADA system regularly performs the polling of the RTUs to obtain data in real time. Such approach presents some critical issues. Due to the nature of the polling process, the SCADA system must periodically query each RTU to recover the data, even if there are not exchanged ones, which could happen during the monitoring of small size resources.
Moreover, the need of having to provide an RTU for each of the components or physical subsystems to be controlled considerably increases the costs associated with the realization of a distributed control system. The aforementioned costs can quickly become exorbitant, especially if there are small or infrequent variations in the field measurements, or in the case of changes to the physical infrastructure, which must correspond to a change in the architecture of the distributed control system or of the RTUs. Likewise, computational costs can also become very demanding if are employed many RTUs to undergo polling.
It would therefore be desirable to have a method capable of limiting the management costs in a distributed control system. Furthermore, it would be desirable to have a method capable of maximizing the management capacity depending on the physical architecture to be controlled and its changes over time. Finally, it would be desirable to have a method capable of an effective control of the physical architecture capable of preventing anomalous management situations connected to random failures, or generated by an unwanted intrusion, of the physical architecture.
Likewise, it would be desirable to have an apparatus capable of defining a distributed control system for a physical architecture with low running costs even in the presence of complex physical architectures or subject to frequent changes.

Method and apparatus for detecting the anomalies of an infrastructure


A method for operating a wind turbine power system that supplies real and reactive power to a grid includes operating a generator of the wind turbine power system up to a first speed limit. The method also includes monitoring a wind speed at the wind turbine power system. When the wind speed drops below a predetermined threshold, the method includes reducing the first speed limit of the generator to a reduced speed limit of the generator. Further, the method includes operating the generator at the reduced speed limit for as long as the wind speed remains below the predetermined threshold so as to optimize a tip-speed-ratio of the wind turbine power system during low wind speeds, thereby increasing power production of the wind turbine power system at low wind speeds.

Generally, during operation of a wind turbine, wind impacts the rotor blades and the blades transform wind energy into a mechanical rotational torque that drives a low-speed shaft. The low-speed shaft drives a gearbox that subsequently steps up the low rotational speed of the low-speed shaft to drive a high-speed shaft at an increased rotational speed, wherein the high-speed shaft rotatably drives a generator rotor. In many conventional wind turbine configurations, the generator is electrically coupled to a bi-directional power converter that includes a rotor-side converter (RSC) joined to a line-side converter (LSC) via a regulated DC link. Each of the RSC and the LSC typically includes a bank of pulse width modulated switching devices, for example insulated gate bipolar transistors (IGBT modules). The LSC converts the DC power on the DC link into AC output power that is combined with the power from the generator stator to provide multi-phase power having a frequency maintained substantially at the frequency of the electrical grid bus (e.g. 50 HZ or 60 HZ).
The above system is generally referred to as a doubly-fed induction generator (DFIG) system, whose operating principles include that the rotor windings are connected to the grid via slip rings and the power converter controls rotor current and voltage. Control of rotor voltage and current enables the generator to remain synchronized with the grid frequency while the wind turbine speed varies (e.g., rotor frequency can differ from the grid frequency). Also, the primary source of reactive power from the DFIG system is from the RSC via the generator (generator stator-side reactive power) and the LSC (generator line-side reactive power). Use of the power converter, in particular the RSC, to control the rotor current/voltage makes it is possible to adjust the reactive power (and real power) fed to the grid from the RSC independently of the rotational speed of the generator. In addition, the generator is able to import or export reactive power, which allows the system to support the grid during extreme voltage fluctuations on the grid.
Typically, the amount of reactive power to be supplied by a wind farm to the grid during steady-state and transient states is established by a code requirement dictated by the grid operator, wherein a wind farm controller determines the reactive power demand made on each wind turbine within the wind farm. A local controller at each wind turbine receives and allocates the reactive power demand between the generator sources (e.g., between generator-side reactive power and line-side reactive power).
In general, the minimum speed (i.e. the cut-in speed) of the DFIG is decided based on the voltage limit imposed by the RSC. Lowering or extending the minimum speed of the turbine increases the operating slip of the DFIG, which mandates the RSC to operate at a higher voltage. In addition to the minimum turbine speed, the reactive power requirement from the DFIG also effects the voltage at the terminals of the RSC. Further, as mentioned, most of the grid codes demand rated reactive power support during the entire operation of the wind turbine, i.e. from cut-in speed to rated speed. Providing the rated reactive power at the minimum turbine speed further forces the RSC to operate at a higher voltage.
During low wind speeds (e.g. from about 3 meter/second (m/s) to about 5 m/s), the wind turbine is supposed to rotate at minimum speed limit. To oblige this, the turbine controller commands to DFIG to operate at a higher TSR (beyond the optimal value). Operation of the wind turbine at the higher TSR, however, is not efficient and will result in wasted energy.
Thus, an improved system and method for operating a wind turbine power system during low wind speeds to allow for a lower or optimized TSR, thereby improving AEP would be desirable in the industry.

System and method for operating a wind turbine power system during low wind speeds to improve efficiency


A plunger for use in a plunger lift system of an oil or natural gas well includes one or more sensor assemblies, each including one or more sensors for measuring various physical and operational conditions during the operation of the well. The data acquired from the sensors is stored in memory within the sensor assemblies and downloaded to the plunger lift system controller when the plunger is located in the catch/lubricator. The data can then be analyzed by the controller or other computer to vary the well's operating parameters to maximize the well's operating efficiency and the data can be used in reservoir management, such as transient testing, reservoir modeling and interference testing.

When a well is first drilled and put into operation, the reservoir pressure in the well is generally sufficient to cause oil and/or gas contained in the well to rise to the surface where it is collected and stored. As the well ages and more wells are placed into a common basin, the well's ability to maintain the pressure necessary to continuously pump oil and/or gas declines due to natural pressure depletion. Once the reservoir pressure is no longer sufficient to permit continuous pumping, a well operator must either install an artificial lift system or cap the well. If a sufficient reserve of oil or gas remains in the reservoir, capping the well may not be economically desirable.
One method of artificial lift is to place a pump in the well to mechanically pump the oil and/or water from the well. However, this can be a very expensive proposition not only requiring an operator to install a pumping system, but also to provide a source of power to run the pump. As can be appreciated, many wells are located in remote locations where sources of energy are not easily or inexpensively recovered. Typically, mechanical pump lift systems are only utilized on wells where the volume of the reserve accessible by the well is considerable enough to justify the expensive of fitting the well with the expensive pumping system and to justify the increased operational expenses.
For wells that are not amenable to a mechanical pumping lift system, a plunger lift system is often used. Plunger lift systems are passive in that they do not rely on an external power source for their operation. Rather, they utilize any remaining well reservoir pressure combined with the well's ability to re-pressurize when the valve connecting the well to the collection tanks or flowline is closed.
Plunger lift systems are generally inexpensive to purchase, as well as, operate compared to alternative types of artificial lift systems. External power is required only for the operation of a small number of solenoids, valve motors and the system's electronic controller. The power levels are low enough that only a small battery pack is necessary.
A well 10 outfitted with a typical plunger lift system is illustrated in FIG. 1. The well comprises a borehole 12 that extends from the subterranean surface to a reserve of oil and/or natural gas. The borehole comprises a tubing string 14 that is encircled by casing 16. The tubing string is comprised of a plurality of tubes interconnected by collar joints (not shown) at their respective ends. A plunger 44 is located in the tubing and is adapted to move freely upwardly and downwardly between the wellhead 18 and the well bottom 20. A bumper 22, most commonly a coil spring, is located at the well bottom to stop the plunger as it completes its descent.
A typical Christmas tree 24 of a plunger lift outfitted well includes a lubricator/catcher 26 that stops the upwardly ascent of the plunger. An arrival sensor 28 is provided at the base of the lubricator/catcher to sense the arrival of the plunger and activate a catcher solenoid 30 to hold the plunger in place until selectively released to travel back to the well bottom. In other variations, a spring-loaded catch arm (not illustrated) is biased into the interior of the lubricator/catcher at its base to catch and hold the plunger once it passes the arm, wherein a plunger solenoid attached to the arm pulls it back and out of the interior to release the plunger. In another variation, it is not necessary to catch the plunger at the surface as the plunger is held in the lubricator until the pressure level dissipates and the plunger falls back to the bottom. Additionally, in this variation shutting a flow line valve will also cause the plunger to fall. A flow line 32 is in operable fluid communication with the tubing string 14 and the solenoid-operated (or motor-operated) flow valve 34, which when opened permits the flow of oil and/or gas to storage tanks (not illustrated) or pipeline (not illustrated). A pressure sensor 38 is also provided to measure the pressure level within the casing.
The arrival sensor 28, the plunger solenoid 30, the flow valve 34 and the pressure sensor 38 are all electronically coupled with a controller module 40. Based on input from the pressure sensor and other sensors and/or the travel time of the plunger, the controller may catch or release the plunger and opens or closes the flow valve to control the lifting of oil and gas out of the well. If no power source is readily available, a solar panel 42 and a battery pack (not illustrated) can be provided to power the controller and the various solenoids and sensors.
FIG. 2 (prior art) is an isometric view of a typical plunger 44. There are many different types of plungers depending on a particular design application and engineering variable concerning the well and any debris or contaminants that might be found in the well. Generally, a plunger is an elongated primarily metallic cylinder or rod that has an outside diameter only slightly smaller than the internal diameter of the tubing string 14. The illustrated plunger generally comprises a plurality of annular wiper ridges 50 that are spaced along most of the plunger's length. The ridges help scrape sand and scale not to mention paraffin and other debris from the sidewalls of the tubing string during the plunger's ascent and descent. Other types of plungers (not illustrated) can have, but are not limited to, (i) smooth outside diameter surface, (ii) spring-loaded metal plates that contact the surface of the tubing string's interior wall, and/or (iii) a segment made of bristles that scrape the tubing string's interior wall. Further, plungers can be flexible to permit them to negotiate around non linear portions of the tubing string during their journey.
A plunger can be solid or it can have a hollow interior. The illustrated plunger is of the hollow variety having an at least partially open bottom end 52 and a plurality of small holes 54 extending inwardly to the interior 56 from between the annular ridges 50.
Some plungers also include a valve at the top of the interior that is in fluid communication with the plunger's topside and that permits the gas and fluids to pass freely through the interior of the plunger when it is open. The valve is opened as the plunger is released from the lubricator/catcher 26 and facilitates the rapid descent of the plunger down the well. When the plunger impacts the bumper 22 at the well bottom 20, the valve closes.
At the top of the illustrated plunger, a fishing neck 58 is shown. The fishing neck permits the well operator to easily retrieve the plunger should it become stuck in the tubing string 14. An operator snakes a wire line with a suitable clamp member down the well to couple with the fishing neck and permit the plunger to be pulled free. As can be appreciated, having to pull tubing to remove a stuck plunger from a well results in downtime that the well could otherwise be producing. The build up of paraffin and other debris, especially around tubing collar joints, can build up over time and can eventually cause a plunger to become stuck. If the operator can determine that there is a debris buildup, an operator would swap out the plunger with a cleaning plunger, such as a brush plunger, to clean the tubing string rather than risk significant downtime if and when the plunger becomes stuck.
Prior art FIG. 3 is a flow chart indicating the operation of controller of a typical plunger lift system equipped well. Once the pressure level in a gas or oil well has dropped to a level that no longer supports the extraction of the oil and/or gas as measured by a pressure sensor 38, the flow valve 34 is closed as is indicated by block 100 and the catcher solenoid 30 may be activated, if necessary, to free the plunger 44 from the lubricator/catcher as indicated in block 105. The plunger descends down the borehole 12 until impacting the bumper 22 and coming to rest at the well bottom 20.
While the plunger 44 is resting on the well bottom 20, pressure in the well increases and is monitored. In an oil well, oil accumulates in the well and percolates past the plunger to fill a portion of the tubing 14. This oil is lifted out of the well when the plunger ascends to the surface. In a primarily gas well, liquids (typically condensate and water) accumulate above the plunger and the casing causing a liquid loading condition. If the liquids are not removed from the tubing string 14, the well can become "loaded up" and cease to produce due to excessive hydrostatic head.
Once sufficient time has elapsed, the pressure in the well reaches a suitable level as measured at the wellhead 18 by the pressure sensor 38, the controller opens the flow valve 34 as indicated in block 115. Almost immediately a pressure differential is established between the portion of the tubing string 14 above the plunger 44 and the region below the plunger causing the plunger to be propelled upwardly carrying any liquid located above the plunger with it. Accordingly, the liquid is moved into the flow line 32 for storage or disposal. Once the plunger passes the arrival sensor 28, it is held in the lubricator/catcher 26 (i) through the activation of the catch solenoid 30, (ii) by way of the spring-loaded catch arm, or (iii) by gas pressure from below as indicated in block 120.
Generally, the plunger will remain in the lubricator/catch as long as the well continues to produce. The controller 40 will monitor the pressure in the well via the pressure sensor 38 as indicated in block 125. Additionally, if the well is equipped with a flow sensor, the flow rate in the flow line 32 can also be monitored. After a certain period of time has passed, however, the pressure in the well and the flow rate will drop to a level that will not support extraction of oil and/or gas and the controller will shut the flow valve 34 releasing the plunger again to repeat the process.

Instrumented plunger for an oil or gas well


Systems and methods for leveraging resources on a computer network to view a file on a client computer written in a format unreadable by the client computer are provided. According to one method, the client computer receives a file in a source format unreadable by the client computer. The client computer broadcasts the format of the received file to a plurality of File Viewing Servers (FVSs) in the network. In response, the client computer receives from at least one of the FVSs a conversion rating, which indicates the respective FVS's ability to convert the source format of the file into a conversion format readable by the client computer. Upon receiving the conversion ratings from the FVSs, the client computer selects the FVS transmitting the highest conversion rating to convert the received file from the source format unreadable by the client computer into the conversion format readable by the client computer.

Thin client computers have recently gained in popularity for providing web browsing and electronic mail applications to users at low cost. The thin client computers achieve low cost by requiring less processing capabilities and memory space than standard PCs. In addition, the thin client computers are generally easier to maintain than standard PCs.
A popular operating system for managing the operation of thin client computers is a Linux operating system. Linux is popular because it may be obtained with little or no license fee. In addition, Linux is an open source operating system, allowing a programmer to easily configure it for the limited processing capabilities and memory space of many thin client computers.
A drawback of a Linux based computer, however, is that a user on the Linux based computer may have a difficult time viewing a file written in a Windows based format, such as Microsoft Word™. Typically, the user on the Linux based computer has two options for viewing the file. The user may utilize a Linux based conversion utility to convert the file into an HTML file, which can then be viewed on the Linux based computer using a web browser application. However, Linux based conversion utilities generally do a moderately poor job of converting a Windows based file into an HTML file. Alternatively, the user may forward the file to a Windows based computer, and then view the file on the Windows based computer. However, this option may inconvenience the user by requiring the user to physically move to the Windows based computer to view the file.

System and method for leveraging networked computers to view windows based files on Linux platforms


The present invention relates to an apparatus and method for recognizing biological named entity from biological literature based on united medical language system (UMLS). The apparatus and the method receives metathesaurus from the UMLS, constructs a concept name database, a single name database and a category keyterm database, which are language resources to be used recognize a named entity, receives each concept name stored in the concept name database, extracts features of each of the concept names by using data stored in the single name database and the category keyterm database, constructs a rule database by creating rules used to recognize the named entity and filtering the rules by using the extracted features, receives a biological literature, extracts nouns and noun phrases that are candidate named entities, applies the rules stored in the rule database to the nouns and the noun phrases, and recognizes the named entities. In the present invention, the biological named entities can be effectively extracted which can be used as important information individual in input literature.

1. Field of the Invention
The present invention relates to an apparatus and method for recognizing biological named entity from biological literature based on united medical language system (UMLS), in which the biological named entity is recognized and grouped.
2. Description of the Related Art
As the volume of biological literature is increased by active study on biology, also increased are demands for extraction of information from the literature at high quality. A protein name, a gene name, and a name of an element of laboratory organism or living organism constitute the core of information in the biological literature that describes results of important biological studies. Accordingly, in order to extract information from the biological literature, names of the biological entity should be exactly recognized and classified first. The information extraction is performed on the literature so as to find information subjects, relation between the information subjects, and information flow of the information subject. Accordingly, even in case of extracting information from the biological literature, the biological named entities that are information subjects in the literature should be first recognized. Generally, as the method of recognizing the biological named entity, there is a rule-based method in which an expert who has biological knowledge creates various language resources and rules on an limited object domain and the named entity is recognized using the created various language resources and rules. There is also a statistic-based method in which a large amount of biological literature learning corpus is constructed and a machine learning algorithm is applied to recognize the named entity. The former method costs much in creation of language resources and rules and the latter method costs much in construction of the biological literature learning corpus.
In the prior art, the technology in which new names are recognized and extracted is registered as U.S. Pat. No. 5,819,265 "processing names in a text" on Oct. 6, 1998. However, the preceding patent does not disclose "the process of the biological literature based on UMLS" and also, the system according to the preceding patent may work erroneously if names in which names or spells appeared in the literature occasionally are similar but meanings thereof are different would be appeared.
In the other prior arts, David A. Campbell and Stephen B. Johnson reported "A Technique for Semantic Classification of Unknown Works Using UMLS Resources" in Proceedings of American Medical Informations Association Symposium, pp 716-720 on November, 1999, and Irena Spasic, Coran Nenadic and Sophia Ananiadou reported "Using Domain Specific Verbs for Term Classification" in Proceedings of the ACL 2003 Workshop on Natural Language Processing in Biomedicine, pp 17-24 on July, 2003. In the method for recognizing the biological named entity, which is disclosed in the prior articles, UMLS and corpus should be simultaneously used and pattern rules are limited to a specific form so that it is limited to recognize the newly generated various named entities.

Apparatus and method for recognizing biological named entity from biological literature based on UMLS

Electronics and Telecommunications Research Institute


A semiconductor structure that includes a silicon substrate which has a top surface, a diffusion region formed in the substrate adjacent to the top surface, a polysilicon gate formed on the top surface of the substrate adjacent to but not contacting the diffusion region, an insulator layer substantially covers the polysilicon gate and the diffusion region, the layer contains a via opening therein, and an electrically conducting plug filling at least partially the via opening providing electrical communication between the polysilicon gate and the diffusion region.

In the semiconductor fabrication process, it is frequently required to make local interconnect between a gate polysilicon layer to N+ and P+ diffusion regions. In the conventional art, this can be accomplished by using buried contacts to provide the necessary electrical connections. A buried contact is formed by the physical contact of a polysilicon layer which is substantially polycrystalline silicon to a region doped by impurity ions in a semiconductor substrate. Buried contacts are most commonly used in a CMOS type of memory circuits.
An enlarged top view and cross-sectional view of a conventional buried contact is shown in FIGS. 1A and 1B, respectively. In a typical fabrication process for buried contacts, a gate oxide layer (not shown) is first deposited on the surface of a silicon substrate 12. On top of the gate oxide layer, a thin layer of polysilicon (not shown) is then deposited to protect the gate oxide layer from contamination. The gate oxide layer and the polysilicon layer are then patterned by a photoresist masking process and etched. Openings (not shown) are formed on the surface of substrate 12 to expose sections of the substrate for the formation of buried contacts. An ion implantation process is performed at the openings to increase the surface dopant concentration for improved contact resistance. Subsequently, the photoresist layer is removed and a layer of polysilicon is deposited onto substrate 12. Thereafter, the polysilicon layer is patterned and etched, typically by a reactive ion etching method, to form a gate electrode 14 for making electrical connection with the diffusion region 16. Metal silicides may be used to reduce the resistivity of the polysilicon interconnect. The metal silicides offer the advantage of lower resistivity while retaining silicon gate characteristics. A BPSG planarization step completes the buried contact fabrication process.
Electrical connection to the other diffusion region 18 can be made by metal contact 22 by first performing a contact masking and etching process. After the formation of the contact holes 24, a thin layer of titanium tungsten or titanium nitride is normally deposited into the contact hole to improve adhesion. A refractory metal plug such as a tungsten plug is then deposited into hole 24. After a tungsten plug etch back process, a metal I layer 26 is deposited to provide connection to other devices.
In order to make a local interconnect from a gate polysilicon to both N+ and P+ diffusion regions by using a conventional buried contact, a complex set of processing steps must be added. This is because that gate polysilicon requires to be doped to both P+ and N+ depending on the diffusion doping the polysilicon is strapping to. Furthermore, in order to minimize inter-diffusion between N+ and P+ doping in polysilicon, additional processing steps are required to lower the diffusivity. This becomes more difficult as design rules are scaled down to the sub-micron range.
There are still other disadvantages of using a buried contact process. For instance, to avoid dopant penetration into the channel region, a P+ doped polysilicon needs to be implanted with the very low energy B11 instead of BF2 to avoid F+ enhanced dopant diffusion. This results in poor manufacturability. For a tungsten polycide process, the buried contact method does not allow an in-situ deposited and doped polysilicon/tungsten silicide structure. The buried contact method also makes it difficult to match the P+ doped and the N+ doped polycide sheet resistance in the case of a titanium silicide process.
Other workers in the field of local interconnects have proposed methods to overcome the drawbacks and disadvantages of the conventional buried contact process. One of such methods is to use a metallic local interconnect strap to shunt from a gate polysilicon to a diffusion region. A typical process is shown in FIGS. 2A and 2B where an enlarged top view and cross-sectional view is shown, respectively. In a local interconnect strap method, a polysilicon gate 32 is first formed without direct contact with the diffusion regions 34 and 36 in a silicon substrate 40. An insulating layer 42 of dielectric material is then deposited on top of the polysilicon and the diffusion regions. Vias are opened through masking/etching processes in the insulator layer 42. After the deposition of a glue layer (not shown), metal plugs 44, 46 and 48 are deposited into the vias. After a tungsten plug etch back and a local interconnect masking/etching process, a local interconnect shunt layer 50 is deposited. A separate shunt 52 is also deposited on metal plug 48 to allow the deposition of another metal plug 54 such that diffusion region 36 can be connected to the Metal I layer 56. The second metal plug 54 is formed in a via opened in the second insulating layer 60 of a dielectric material.
The local interconnect strap method, even though accomplishes the electrical connection between a polysilicon gate and a diffusion region, is a process-intensive method. For instance, it requires the additional processing steps of depositing an insulating layer between the local interconnect and the gate polysilicon, of opening vias in an insulating layer, of patterning and depositing the local interconnect layer. Moreover, from a topological standpoint, the process requires much larger layout area than a buried contact at the intersection of the gate polysilicon to the diffusion region.
It is therefore an object of the present invention to provide a local interconnect between a polysilicon gate and a diffusion region that does not have the drawbacks and shortcomings of the prior art interconnect.
It is another object of the present invention to provide a metal plug local interconnect for connecting a polysilicon gate to a diffusion region.
It is a further object of the present invention to provide a metal plug interconnect between a polysilicon gate and a diffusion region that only requires a minimal number of additional processing steps.
It is still another object of the present invention to provide a metal plug local interconnect that does not require the formation of a buried contacts.
It is yet another object of the present invention to provide a metal plug local interconnect between a polysilicon gate and a diffusion region that does not require the use of a local interconnect strap.
It is another further object of the present invention to provide a metal plug local interconnect between a polysilicon gate and a diffusion region wherein the metal plug local shunt can be formed in a single metal contact formation step.


A shedding device as provided for textile machines which includes oppositely movable lifting blades (41) and pulling elements (42) which are reciprocally movable between a lower shed position and an upper shed position and which are interconnected in pairs by a connecting member (1). The connecting member (1) is connected through a pulley block (2) to a heddle (7) and a retention device (12) is located at a lower shed position and between the pulling elements (42) to control the latter in accordance with the particular pattern program. The insertion device (12) has a wedge-shaped base (17) including a base edge (17a) directed toward the harness string (6). Magnetic pull areas (23, 24) are formed at inclined surfaces (20, 21) of the wedge-shape base (17) and through an associated air gap (A) progressive movement of the coupling portion (46) of each pulling element (42) is effected upon magnet energization or coupling/uncoupling operations at low forces and under relatively quiet operation.

The present invention relates to a shedding device.
A device of this kind is disclosed in the U.S. Pat. No. 4,969,490. In this device the pulling element comprises a supporting heel, which is taken up in the lower shed position by a groove shaped recess of a stationary supporting ledge.
A relatively large distance is present between the electromagnet and the pulling element, such that the pulling element must be pivoted forcefully by the lifting blade toward the electromagnet and must be pivoted back when the electromagnet is not excited by the complete harness string. During this continuous pivoting back and forth of the pulling element, noise is generated and friction occurs on the one hand between the pulling element and the supporting heel and on the other hand between the pulling element and the lifting blade. Such friction leads to the wearing of one or the other or both parts and thus is a serious structural and functional drawback. A further weak point consists in that the restoring force of the pulling element must be produced by the complete harness string. Because the frictional force between the supporting ledge and the supporting heel counteracts same, the complete harness string must be tensioned stronger than necessary.

Electro magnetic shedding device for a textile machine