The present invention provides methods and compositions that reduce target-independent primer extension or enhance template dependent primer extension. The methods and compositions of the present invention are applicable not only in PCR, but also in nucleic acid sequencing, genotyping, and other applications employing extension of a primer in a target-dependent manner.

Research in biotechnology directed to sequencing nucleic acids is of major importance and has been used to sequence the human genome, make diagnostic probes, treat diseases and for other research applications. Primer extension plays a major role in conducting this research.
Primer extension has diverse applications, such as, for example, various DNA and RNA sequencing methods, polymerase chain reaction (PCR) applications, cloning, enzymatic synthesis of nucleic acids, polymorphism identification, haplotyping, and multitude of other nucleic acid analysis methods. Over the last decade, minisequencing, or single base extension (SBE) technologies, have been used to identify nucleic acids at particular sites, especially in the field of genomic analysis. SBE has been developed into high throughput processes through multiplexing that allows multiple simultaneous nucleic acid identification. Multiplexing has been extended with the advent of new immobilization chemistries to the scale of nucleic acid microchips, or arrays. Thus, SBE can now be performed where the primers are extended and immobilized on a chip, for example, by tag capture methods where extended primers are captured at known positions on the surface of addressable arrays to identify nucleic acids at particular sites. Many other methods are known in the art that use primer extension to identify nucleic acids. Each of these methods relies on the fidelity, efficiency, and accuracy of the primer extension reaction.
There has been tremendous interest in identifying polymorphic sites across the genome. Of particular interest are single nucleotide polymorphisms (SNPs). SNPs are the most common variations in the human genome, occurring at a frequency of about one in 1,000 base pairs. One method of detecting SNPs is by SBE. In one embodiment of SBE, primers are immobilized on solid supports, such as for example, chips, beads or microspheres. These solid supports may have detectable signals or bear tags that allow easy SNP identification. These detectable signals or tags allow genetic information to be easily sorted by any number of methods, including, for example, electrophoresis, mass, volume, or by applying the tagged beads or microspheres to complementarily tagged arrays. Accordingly, large amounts of information can be analyzed in a single experimental run. However, difficulties can occur in analyzing this information due to signal to background noise. For example, the magnitude of noise relative to the expected signal should be low in order to accurately determine the identity of a polymorphic site with a high degree of precision and accuracy. Noise in such a primer extension assay is often sequence-dependent and primarily results from template-independent primer extension, particularly in platforms employing primers immobilized in close proximity to one another, such as on arrays or chips.
Unwanted primer-primer interactions are a common source of template-independent noise. These interactions may occur between two separate but identical primer molecules, between two portions of a single primer molecule, or between two separate but not identical primer molecules. Types of interactions that commonly generate significant noise are those that allow hybridization to occur between two primers, or within a single primer, so that primer extension occurs in the absence of template or target nucleic acid(s). For example, sometimes a single primer molecule can fold into a hairpin structure, resulting in the outcome that the primer also acts as its own template. Alternatively, two primers may interact sufficiently well so that one is capable of serving as template for the other. This results in spurious signal generation because extension of the primer occurs independent of the target nucleic acid sequence.
Attempts have been made to reduce or eliminate unwanted primer interactions by conducting hybridization at elevated temperatures. However, on micro-arrays, primer interactions are more difficult to overcome because primers are immobilized to the surface of the array or chip in very close proximity to one another and array-based protocols may not allow for elevated temperature. Further, temperature effects would tend to disperse primers spatially, but array technologies are based on localized immobilization of the primers, and so spatial separation, by definition, is contradictory to the definition of arrays.
In the case of primer extension in thermal cycling, such as by a thermostable polymerase in PCR, multiple factors are optimized in order to obtain a desired outcome and reduce the likelihood of undesirable primer-primer interactions. For example, varying magnesium chloride concentrations, employing stabilizing additives such as dimethyl sulfoxide, glycerol, formamide, betaine, ammonium sulfate, or commercial or proprietary enhancers, stabilizers, and hybridizing agents are some approaches aimed at minimizing unfavorable primer-primer interactions, or mispriming events, as well as manipulation of reaction conditions such as pH, buffers, ionic and non-ionic detergents and surfactants. Optimization kits are commercially available that aid users in manipulating these factors to some extent. However, multiple factors must be optimized, which can result in costly and time-consuming optimization trials, and certain optimization conditions my not be compatible with array technologies and methods. Further, higher multiplexing levels will only exacerbate sequence-dependent and sequence-independent noise issues, rendering such optimization efforts increasingly difficult—if not impossible—to achieve by biochemical means alone.
Other attempts to avoid primer-primer interactions involve hot start PCR methods. Some hot start methods include inhibition of polymerase by low temperature, or adding polymerase after the melting and annealing step. Hot start PCR improves specificity, sensitivity and yield of the PCR reaction. Other methods avoid nonspecific, or target-independent primer extension by omitting, inhibiting, or sequestering the thermostable polymerase in the initial denaturation and annealing reaction, such as by reversibly binding to the polymerase an inactivating antibody.
Primer self-complementarity also adds to unwanted target-independent extension resulting in inaccurate primer extension and noise. Self-complementarity is the ability of a primer to self-anneal or anneal with another copy of itself. Although self-complementarity can be highly undesirable, it may not be possible to avoid every instance of self-complementarity in primer design for a variety of reasons. For example, the target nucleic acid may contain regions or repetitive stretches of self-complementarity, and thus amplification or primer extension might require primer structure reflecting these repetitive regions.
There are many computer programs used in primer design that limit use of primers that exhibit self-complementarity, or limit the degree of self-complementarity. However, such programs may not be useful in the situation where the target sequence for which the primer is being synthesized bears a region of self-complementarity. For example, if a target nucleic acid molecule has a sequence that requires the use of primers having a palindromic sequence at its 3′ terminus, such as for example a restriction site, self-complementarity might not be avoided.
Palindromes are sequences that symmetric. That is, they read the same from the 5′ to 3′ direction as they read from the 3′ to 5′ direction. One characteristic of a palindromic sequence is that it is self-complementary, and thus generally able to hybridize to itself, or other copies of itself. In the case that a palindrome is at the 3′ terminus of the primer, it can hybridize with the 3′ terminus of another primer molecule that is acting as template, confounding attempts to extend the primer employing the target nucleic acid as a template. Generally, the closer a region of self-complementarity is to the 3′ end of a primer, the more likely it is to interfere with primer extension. Efforts can be made to minimize the likelihood of interference, such as maintaining short primers 30 to 40 nucleotides in length, and matching thermodynamic parameters for primers. However, this is not always a viable solution due, to constraints set by the sequences of the target nucleic acid, as discussed above.
Physical separation of an essential reaction component prior to the first denaturation step can often reduce target-independent priming. Denaturation of target nucleic acid before the addition of a polymerizing agent or magnesium chloride can improve the specificity and sensitivity of the primer extension reaction, but requires an added step where tubes are reopened to add the missing component. This added step becomes unwieldy when running a multitude of samples.
Other attempts to reduce target-independent primer extension employ reversible inhibition of the polymerizing agent by, for example, an antibody, which can be effective in some circumstances. However, this approach is more expensive and time consuming and requires an added step, which is undesirable when running a multitude of samples.
Enhancers can be employed to increase yield, specificity and the likelihood of overcoming high GC content or long templates. Such enhancers include compounds which often can increase yield, such as nonionic detergents like, for example, Tween-20, or enzyme-stabilizing agents such as bovine serum albumin, or other compounds such as betaine, glycerol, dimethyl sulfoxide, polyethylene glycol, or salts. Improvements in specificity can be achieved through addition of formamide to the reaction mixture, which tends to destabilize mismatched primers.
Target-independent primer extension may occur not only with heat-stable polymerases in a polymerase chain reaction, but in any application employing primer extension on a target nucleic acid. Such applications include those for nucleic acid sequencing, genotyping, and a host of other primer extension methods.
Based on the foregoing, there is a need for methods and compositions that allow primer extension reactions to run maximally with respect to key parameters, such as efficiency, fidelity, accuracy, and high signal-to-noise ratio. The present invention addresses this need and provides methods and compositions that reduce target-independent primer extension or enhance template dependent primer extension. The methods and compositions of the present invention are applicable not only in PCR, but also in nucleic acid sequencing, genotyping, and other applications employing extension of a primer in a target-dependent manner.

Primer extension using modified nucleotides


A fuel cell including a unit cell and a separator panel alternatingly stacked on one another. The unit cell includes an electrolyte membrane sandwiched between a fuel electrode and an oxidant electrode. The separator panel includes parallel fuel flow paths extending from a fluid supply port to a fluid discharge port for supplying fluid fuel to the fuel electrode and parallel oxidant flow paths extending from a fluid supply port to a fluid discharge port for supplying oxidant fluid to the oxidant electrode. At least the oxidant flow paths include groups of parallel flow paths, which extend back and forth within divided regions of the main surface of the separator panel. The oxidant flow paths may include groups of parallel flow paths, positions along the groups of the parallel flow paths at equal distance from the respective fluid supply port being distributed substantially evenly over the main surface of the separator panel. Also, groups of parallel flow paths extend back and forth within a region defined by a projection of the divided regions through which the oxidant flow paths extend. The ridge width of ridges defined between grooves within the parallel flow path group is smaller than the ridge width of the ridges defined between the grooves of the parallel flow path group adjacent to each other.

This invention relates to a fuel cell which is used in an electric vehicle and the like and a manufacturing method therefor. While this invention will be described in relation to a solid-state high polymer type fuel cell, it is also applicable to a phosphoric acid fuel cell.
As is well known, the fuel cell is an apparatus having a pair of electrodes and an electrolyte sandwiched therebetween, a fuel is being supplied to one of the electrodes and an oxidant being supplied to the other of the electrodes thereby achieving an electrochemical reaction between the fuel and the oxidant within the cell to convert chemical energy directly into electrical energy.
According to the kind of the electrolyte, fuel cells are classified as including a so-called solid polymer fuel cell in which a solid polymer electrolyte membrane is used as an electrolyte, and a phosphoric acid fuel cell in which phosphoric acid is used. Recently, a solid polymer fuel cell received attention as a fuel cell which can output a nigh power. When hydrogen gas is supplied to a fuel electrode and oxygen gas is supplied to an oxidant electrode, for example, to produce an electric current in an external circuit, the following reactions as shown in the following chemical reaction formulae (1) and (2) occurs:
anode reaction: H2xe2x86x922h++2exe2x80x83xe2x80x83(1)
cathode reaction: 2H++2exe2x88x92+(1/2)O2xe2x86x92H2Oxe2x80x83xe2x80x83(2)
When these reactions occur oxygen becomes protons on the fuel cell electrode and move together with water through the electrolyte up to the oxidant electrode, where they react with oxygen on the oxidant electrode to generate water. Therefore, in order to operate the above fuel cell, it is necessary to supply and discharge the reaction gas and to take out the electric current
Some examples of the separator panel for taking out the electric current from the fuel cell and for efficiently circulating the gas and water can be found in Japanese Patent Laid-Open Nos. 58-161270, 58-161269 and 3-206763.
FIG. 15 is a sectional View for explaining the overall structure of a unit cell constituting the fuel cell disclosed in Japanese Patent Laid-Open No. 3-206763, in which reference numeral 1 and 2 designate electrically conductive separator panels, 3 is an oxidant electrode, 4 is a fuel electrode and 5 is an electrolyte member using a proton-conductive solid polymer, the electrolyte member 5, the oxidant electrode 3 and the fuel cell 4 constitute a unit cell 6.
FIG. 16 is an explanatory view showing the top surface of the separator panel of the fuel cell shown in FIG. 15, the explanation thereof will be made in conjunction with FIG. 15.
That is, the reference numeral 20 is a major surface of the separator panel 1, 21 is an electrode support portion of the separator panel 1 for supporting the electrode 3, 22 is an oxidant supply port provided in the separator panel 1 for supplying air as the oxidant, 23 is an oxidant discharge port for discharging air, 24 is a fuel supply port for supplying the fuel therethrough and 25 is a fuel discharge port for discharging the fuel.
In the separator panels 1 and 2, an oxidant flow path 10 and a fuel flow path 11 are defined by grooves cut into the main surface 20 and a space surrounded by the electrodes 3 and 4.
The operation of the fuel cell will now be described in conjunction with FIGS. 15 and 16. Oxygen supplied from the oxidant supply port 22 of the separator panel 1 is supplied to the oxidant electrode 3 through a plurality of parallel oxidant flow path 10 and the fuel is supplied to the fuel electrode 4 through the fuel gas flow path 11 in a similar manner to the flow of the oxidant. At this time, since the oxidant electrode 3 and the fuel electrode 4 are electrically connected at the outside, the foregoing chemical reaction formula (2) occurs on the side of the oxidant electrode 3 and the reduced reaction gas and water are carried through the oxidant gas flow path 11 and are discharged from the oxidant discharge port 23. On the side of the fuel electrode 4, the reaction of the above reaction formula (1) occurs and the reduced reaction gas is similarly discharged from the fuel discharge port 25 through the fuel gas flow path 11. The electrons obtained by this reaction flow from the electrodes 3 and 4 through the electrode support portions 21 and through the separator panels 1 and 2.
The oxidant flow paths 10 are formed on one of the surfaces in a serpentine manner in cross section so as to define a plurality of parallel grooves. Also, the fuel gas flow paths 11 are also a plurality of grooves similar to the oxidant flow paths 10.
In such a fuel cell, gas diffusion necessary for the reaction is promoted and the water generated at the oxidant electrode is efficiently discharged by making the boundary layer thin by increasing the gas flow speed and by making the gas flow path long by forming it into a serpentine shape.
It has also been proposed that the region be completely divided to define serpentine flow paths as shown in FIG. 17, which is a perspective view of the separator panel disclosed in Japanese patent Laid-Open No. 62-40169. In the figure, the reference numeral 7 is a separator panel, 8 and 8a are grooves, 9 and 9a are ribs. According to this measure, an inlet and an outlet for a single fluid occupy substantially the complete length of one side of the separator panel and it is difficult to provide for another fluid.
Also, a flow path in which a parallel flow path is simply folded and returned is shown in FIG. 18 which is a perspective view of a separator panel disclosed in WO96/20510. In the figure, the reference numeral 71 is an airflow path, 72 is a fuel supply port, 73 is an air supply port, 74 is an air discharge port and 75 is a fuel discharge port
In the conventional separator panels, the reaction is promoted at the region where the concentration of the fluid flowing through the flow path is high and the current density is increased within that region, making the current density over the entire separator panel non-uniform. However, this non-uniform current density is not considered at all, so that the effective reaction area is decreased, resulting in lowered properties.
In the above conventional fuel cell, the voltage generated by one unit cell is not greater than 1V and it is necessary to stack more than 100 unit cells and separator panels as disclosed in Japanese Patent Laid-Open No. 4-121914 to obtain a voltage of equal to or more than 100V which is practically necessary.
However, stacking more than 100 unit cells and separator panels at one time is not good in work efficiency and not only the precision maintenance of the alignment of the stacked elements is difficult, but also they are displaced due to vibration or the like during the operation and, in worst case gas leakage may occur due to the displacement of the gas supply port or gas discharge port.
While a fuel cell having a conventional separator panel is arranged to increase the gas flow speed to discharge the formed water as discussed above, the gas leaks between a group of the flow paths and a second group of bent flow paths next to the first group of the flow paths.
Accordingly, an object of the present invention is to provide a fuel cell which has a uniform reaction distribution over the separator panel and an improved performance.
Another object of the present invention is to provide a method for manufacturing a fuel cell in which a precisely assembled fuel cell stack can be manufactured at low cost and high efficiency.
Another object of the present invention is to provide a fuel cell that has a stable mechanical configuration during operation.
A further of object of the present invention is to provide a fuel cell in which the gas leakage can be prevented and which can be mass-produced and is capable of generating a high voltage output.
With the above object in view the fuel cell of the present invention comprises a unit cell and a separator panel alternatingly stacked on one another. The unit cell includes an electrolyte membrane sandwiched between a fuel electrode and an oxidant electrode. The separator panel includes a plurality of parallel fuel flow paths extending from a fluid supply port to fluid discharge port for supplying fluid fuel to the fuel electrode and a plurality of parallel oxidant flow paths extending from a fluid supply port to a fluid discharge port for supplying oxidant fluid to the oxidant electrode. At least the plurality of oxidant flow paths comprise a plurality of groups of parallel flow paths, which extend back and forth within divided regions of the main surface of the separator panel.
The plurality of oxidant flow paths may comprise a plurality of groups of parallel flow paths, positions along the plurality of groups of the parallel flow paths at equal distance from the respective fluid supply port thereof being distributed substantially evenly over the main surface of the separator panel.
Also, the separator panel may comprise a plurality of parallel coolant flow path for allowing a coolant to flow therethrough, and the plurality of coolant flow paths may include a plurality of groups of parallel flow paths, which extend back and forth within a region defined by a projection of the divided regions though which the oxidant flow paths extend.
The method for manufacturing a fuel cell of the present invention comprises the steps of preparing a unit cell having an electrolyte membrane sandwiched between a fuel electrode and an oxidant electrode and having a first through hole on an electrode surface, and a separator panel having a plurality of fuel flow paths extending for supplying fluid fuel to the fuel electrode and a plurality of oxidant flow paths for supplying oxidant fluid to the oxidant electrode and having a second through hole on a main surface thereof. Then, the unit cell and the separator panel are stacked one on another to make stacks and an intermediate adapter having a third through hole is inserted into the first and second through holes to hold the stacks into unit blocks. The plurality of unit blocks are stacked and a clamp shaft is inserted into the third through hole of the intermediate adapter of the stacked unit blocks to obtain a stack of the unit blocks, and then the stack of the unit blocks is clamped by the clamp shaft.
The intermediate adapter may be a cylinder having an outer diameter for allowing it to be inserted into the first and second through holes, and the third through hole may have dimensions for allowing the shaft to extend therethrough.
The first and second through holes and the intermediate adapter may have an oval cross-sectional shape.
Also, the fuel cell may comprise a unit cell having an electrolyte membrane sandwiched between the fuel electrode and the oxidant electrode, a separator panel having-formed therein fuel flow paths for supplying fuel fluid to the fuel electrode and oxidant flow paths for supplying oxidant fluid to the oxidant electrode, an intermediate adapter having a through hole therein and inserted into the unit cell and the separator panel to hold them in a stacked relationship to form unit blocks, and a clamp shaft extending through plurality of the unit blocks and clamping them into a stack of unit blocks.
The ridge width of ridges defined between grooves within the parallel flow path group may be smaller than the ridge width of the ridges defined between the grooves of the parallel flow path group adjacent to each other.
The ridge width between the adjacent groups may be increased as the distance from the folded portion increases.


A modular parser architecture and methods related thereto make use of a number of miniparsers. Each miniparser is capable of receiving input and generating an output dependent thereon. In one embodiment, a lexer or a miniparser capable of lexical analysis receives certain code and provides an abstract syntax tree. Each miniparser performs operations on a set of syntactical constructs to produce a corresponding output syntax tree, which in turn may become an input syntax tree for a next miniparser which may operate on a different set of syntactical constructs.

1. Field
The invention relates to parsing technology, in particular, to techniques for decomposing a complex parser, such as for a computer programming language, into successive passes of comparatively simple miniparsers that operate on the outputs of respective predecessor miniparsers.
2. Description of the Related Art
In computer technology, a parser is a program, usually part of a compiler, that receives input in the form of sequential source program instructions, interactive online commands, markup tags, or some other defined interface and breaks them up into parts (for example, the nouns (objects), verbs (methods), and their attributes or options) that can then be managed by other programming (for example, other components in a compiler). A parser may also check to see that all input has been provided that is necessary.
Parsers typically translate an input information encoding such as source code text into abstract syntax trees in two steps: first, a lexical analyzer or lexer transforms source code text into a series of tokens or word-like pieces; then a parser converts the tokens into a parse tree. Abstract syntax is a representation of data (e.g., a program being compiled) which is independent of machine-oriented structures and encodings and also of the physical representation of the data. In the case of compilation, the syntax is called concrete syntax and includes all the features visible in the source program such as parentheses and delimiters. The concrete syntax is used when parsing the program or other input, during which it is usually converted into some kind of abstract syntax tree. An abstract syntax tree (AST) is a data structure representing something which has been parsed, often used as a compiler or interpreter's internal representation of a program while it is being optimized and from which code generation is performed. The range of all possible such structures is described by the abstract syntax. A compiler's internal representation of a program will typically be specified by an abstract syntax in terms of categories such as "statement", "expression" and "identifier". This is independent of the source syntax (concrete syntax) of the language being compiled (though it may be similar). A parse tree is similar to an abstract syntax tree but it will typically also contain features such as parentheses which are syntactically significant but which are implicit in the structure of the abstract syntax tree.
Although interactive programming environments have found widespread acceptance, most classic parser architectures hail from an era of when computation was a scarce resource. Bottom-up parser generators have succeeded in two important goals: languages such as the BNF ("Backus Normal Form" or "Backus-Naur Form") provide a concise and elegant notation for the expression of a language's syntax, and parsing algorithms such as LR-1 parsing minimize the time and space required to actually perform a parse. The strengths of bottom-up parser generators were critical in the environments that prevailed in the last millennium, but make little difference in many projects today and in the future. For example, when virtual machines feature an interactive programming environment in which only individual methods are expected to be compiled at a time, and when software is developed on machines with fractional-gigahertz processors and hundreds of megabytes of main memory, a parser can afford decreased performance. Thus, parsing efficiency is not always as important as development time.
Moreover, the strengths of traditional parser architectures come with weaknesses. First, the grammar itself requires a parser. A grammar can provide a formal definition of the syntactic structure of a language which is often given in terms of production rules which specify the order of constituents and their sub-constituents in a sentence or string. Of course, the grammar parser can be generated from a grammar, but some time is needed to get over the bootstrap hump. Next, bottom-up, table-driven parsers can be difficult to modify. This problem is merely a specialized case of a challenge that dogs the heels of all nonprocedural languages; a change to the specification, in this case the grammar, frequently creates unanticipated consequences. With LR parser generators, this issue typically surfaces when a programmer makes a change to the grammar only to discover that she has created unforeseen ambiguities. The hard-won description of the target language's grammar is concise but not malleable. Grammar-driven parsers require implementation effort for the grammar, and bottom-up grammar driven parsers can be brittle.
Even when a traditional, grammar-driven, parser has been tweaked to accept the desired grammar, the parser's output leaves much to be desired. A grammar-driven parse produces a concrete syntax tree, whose topology results from the hierarchical relationships between the grammar's productions. But the grammar is as much a function of what is parsable by a particular algorithm as it is of the target syntax. For example, left- or right-recursion in the grammar can induce a tall, skinny subtree when a short, flat one would be better. Or, if the grammar is incompletely factored as happens all too often, different kinds of tree nodes may redundantly implement the same semantic construct, reflecting its contextual syntactic legality instead of its meaning. Therefore, the choice to employ a grammar-driven parser frequently implies a commitment to write a post-processing system to clean up and reshape the parse tree. Not only does this system add implementation effort to a parser, but it also further impedes malleability. Whenever the grammar is perturbed, the tree postprocessor must also change.
Traditional parsers typically use a top-down recursive-descent parsing algorithm. A traditional such parser would recursively descend the grammar, traversing each token once (modulo look-ahead), in order to build the final parse tree. For example, in a typical implementation of a recursive-descent parser, at every juncture, each possibility must be tried. Because an attempt may fail, each token may actually be examined may times. Each stage of the parse must correctly choose between all possible results that could possibly start with what has already been parsed. But the only data available to make this decision are the tokens lying ahead in the input stream. Recursive descent optimizes performance but makes it harder to generate a correct parse.

Modular parser architecture with mini parsers


A feed device for a superplastic press-forming press has a slide that moves vertically and a base between which is held a tool having a cover and a bottom die enclosing a forming tool, which includes at least one heating shuttle to transport the bottom die, equipped with the forming tool and a cover, with the heating shuttle adapted to complete the press and constitute the base of the press during a hot-press forming operation.

1. Field
The disclosed embodiments concern an improvement in superplastic press forming systems, particularly an advanced feed device for such a press forming system.
2. Brief Description of Related Developments
Superplastic press forming SPF is a method of forming strip or sheet-metal-based pieces to make complex, resistant light-weight pieces with very large extensions.
It is based on heating metal strips or sheets placed in a forming tool with a cavity and applying pressure with gas injected into the cavity of the tool to push the piece against the wall of the cavity of the forming tool.
For aluminum-based alloys, the temperature of the cavity must reach a value of 450° C. to 500° C. and for titanium-based alloys, the temperature must commonly reach 890° C. to 920° C.
An example of pressing and hot pressing by superplastic deformation is known from document US 2006/0260373 A1 and an example of a complex piece made by such a process is known from FR 2 739 832 A1.
A conventional press for forming simple sheet metal is sketched in FIG. 1 of the prior art.
The press includes a hot press slide 1, a cover 2, forming the top part of the cavity that holds and forms the piece 3, a forming tool 4 that fits into a bottom die 5 and a heating support forming the base 6 of the press.
The bottom part of the cover 2 and the top part of the forming tool form two hot-forming die halves between which the sheet metal 3 being formed is inserted.
A pressurized gas G is inserted into the cavity through one or more conduits 6 to apply pressure PG to the sheet metal 3 and push it against the forming tool 4.
When the piece is being formed, mechanical pressure PM is applied to the slide of the press to clamp the edge of the piece and seal the cavity.
One of the problems with the process is that the time for heating the various parts of the tool is very long, commonly two days to reach a high uniform temperature for the tool components, so the process can be used.
This is not really a problem when parts are made in large series with the same shape, since this heating time similar to the start-up time for the process is negligible compared to the time the tool is used.
Moreover, to increase the pace of the press, it is known how to preheat the pieces outside the press to prevent them from spending too long in transit to the press.
In this context, document US 2006/0237420 A1 describes a device for heating and transferring parts that makes it possible to feed the press with preheated parts.
This device has a transport shuttle for the metal strips or sheets intended to make the piece and means of heating the metal strips.
On the other hand, in the case of small series of pieces with different shapes, preheating the metal strips or sheets is not enough to optimize the yield of the process and, notably, the time necessary for preheating the die half of the forming tool becomes a disadvantage compared to the time for forming the pieces.
In addition, in such case, there is a need to let the forming tools cool to replace them, which adds to the time that the press is not available.
The heating and cooling phases in particular can represent up to 30% of the load on the press for small and medium-sized series.

Advanced feed device for a superplastic press forming system


A centrifugal compressor (P) is provided with: a casing (10) which forms an impeller inlet flow path (11), an impeller flow path (12), an impeller outlet flow path (13), and a scroll (14); and an impeller (3) which is arranged in the impeller flow path (11), wherein the casing (10) is provided with a casing body (15) and a heat conduction inhibiting part (16) which is disposed to heat conduction paths to the impeller inlet flow path (11) from at least the impeller outlet flow path (13) and the scroll (14) so as to inhibit heat conduction to the impeller inlet flow path (11) from at least the impeller outlet flow path (13) and the scroll (14).

PTL 1 discloses a technology of inhibiting a choked flow rate from being reduced so as to expand an operation range of a centrifugal compressor while improving a surge margin, by decreasing a circulation resistance of air that flows in an intake air channel of the centrifugal compressor in a turbocharger.
More specifically, in PTL 1, in order to decrease the circulation resistance of intake air flowing in the intake air channel, there is provided a parallel flow generating unit that straightens the flowing in parallel with a rotary shaft that enters the intake air channel from an inlet. The parallel flow generating unit includes an outer cylinder member that fits in an inner circumferential wall of an upstream-side housing and a plurality of guide vanes arranged along the inner circumferential wall of the outer cylinder member at equal intervals in a circumferential direction.
Further, PTL 1 discloses that parallel flow generating means described above from the viewpoint of cost reduction is integrally formed of an aluminum material or a resin.

MITSUBISHI HEAVY INDUSTRIES ENGINE & TURBOCHARGER, LTD.


A method of controlling a digital photographing apparatus that can easily determine a quality of a photographed image from an image displayed on a display panel included in the digital photographing apparatus, and the digital photographing apparatus using the method. The method includes: performing photographing operation in two or more photographing modes to obtain photographed images in response to a single activation of a shutter button; and displaying simultaneously: (1) a plurality of first images obtained by reducing the photographed images or by reducing the photographed images that are corrected, and (2) a plurality of second images that correspond to parts of the first images.

1. Field of the Invention
The present invention relates to a method of controlling a digital photographing apparatus and a digital photographing apparatus using the method, and more particularly, to a method of controlling a digital photographing apparatus that easily determines image quality from images displayed on a display panel included in the digital photographing apparatus, and a digital photographing apparatus using the method.
2. Description of the Related Art
In general, digital photographing apparatuses store image files obtained by photographing operations in a storage medium, and display the image files stored in the storing medium in a display mode. The image files can also be displayed in a photographing mode.
Conventional digital photographing apparatuses display entirely reduced images of photographed images on a display panel in the display mode. However, when the photographed images have imperfections and are not clear due to, for example, shaking of the camera or movement of the photographed subject, the imperfections of the reduced images are not perceptible and appear on the display panel as if they are photographed clearly. In addition, when noise exists in photographed images due to sensitivity problems, the noise is not perceptible in the reduced images displayed on the display panel, and the photographed images are displayed as if they are clear. Therefore, a user has to enlarge and examine the reduced images in order to identify whether there are imperfections in the photographed images. In addition, besides the clarity of the images, the reduced images frequently have to be enlarged to determine if the images are photographed as the user intended.
In addition, in conventional digital photographing apparatuses, when a plurality of images of similar subjects to each other are displayed on the display panel simultaneously, the entirely reduced images of the photographed images are displayed on the display panel. Therefore, it is difficult to check individual characteristic of the plurality of images of the similar subjects on the display panel. Thus, if the user wants to choose an image that is photographed as the user intended from the plurality of similar images, the reduced images have to be enlarged and identified again, thereby increasing inconvenience.

Method of taking an image with multiple photographing modes and digital photographing apparatus using the method


In a cylindrical drill bit comprising a tool body with a head having a front face and a cylindrical shaft for chucking the tool body, a hard metal cutting plate structure is mounted on the front face of the head and includes cutting edges formed integrally with the hard metal cutting plate.

The invention relates to a drill bit, and more specifically, to a cylindrical bit with hard metal cutting edges. Such a cylindrical bit is a drilling tool which has a disc-like, that is a cylindrical, head provided at its front side and, possibly at its circumference, with a number of cutting edges.
Such drill bits consist usually of a tool body of tool steel which includes a head into which cutting edges of hard metal are inserted or onto which the cutting edges are soldered or welded. The manufacturing process for such drill bits with individually manufactured and installed cutting edges however is time-consuming and expensive.
The alternative possibility to make the tool completely from hard metal is not desirable either since such hard metal is very expensive, whereby the tool would become even more expensive.
It is therefore the object of the present invention to provide an improved design of a cylindrical bit, which is easier and less expensive to manufacture.
In a cylindrical drill bit comprising a tool body with a head having a front face and a cylindrical shaft for chucking the tool body, a hard metal cutting plate structure is mounted on the front face of the head and includes cutting edges formed integrally with the hard metal cutting plate.
The drill bit according to the invention consists accordingly of a body of a tool steel with a head formed by a simple disc having a flat front face. On the front surface, a cutting plate is disposed which consists completely of hard metal and which is attached to the front face by soldering or cementing. This hard metal plate is in the form of a spoke wheel that is it does not have the form of a flat disc, but it is provided with openings whereby a substantial amount of hard metal is saved. The cutting plate may be manufactured by injection molding from a hard metal powder which is mixed with a medium that makes it flowable so that it can be molded by injection molding, as is known per se. The cutting plate is therefore molded in essentially its final shape that is with cutting edge structures which later only need to be ground to form the cutting edges.
The front surface of the tool body may be provided with fitting pins, which in co-operation with the openings in the cutting plate provide for a centering of the cutting plate on the tool body head when placed thereon.
An embodiment of the invention will be described in greater detail below on the basis of the accompanying drawings.

Cylindrical bit with hard metal cutting edges


A self checking interlock modular control system allows for an unlimited number of interlocks to be connected into a single interlock control circuit. The interlock control system provides a method of determining if the components within each interlock module of the control system function correctly when the individual interlocks are opened and closed. The interlock control system has redundant components to provide a circuit path to insure that the interlock control system will open circuit the output if one of the components fails.

Interlock systems that control the operation of various types of machinery are well known. In most instances, these interlock systems are required to be hardwired, electromechanical, and self-checking. The interlocks typically consist of a number of normally closed contacts connected in series to energize a control relay. These interlocks include, but are not limited to emergency stop push buttons, limit switches, open door indicators, palm switches, and so on. As long as the interlocks are closed, the relay remains energized and the machine can operate. Opening any one of the interlocks causes the relay to deenergize and the machine is shut down. These normally closed contacts will always have a finite voltage drop across them. With more complex machinery, the number of contacts wired in series becomes very large. The ohmic losses across these contacts is such that the sum of these voltage drops may prevent the control relay from energizing. As a result, other systems must be utilized. One method to overcome this drawback is to divide the interlocks into smaller groups of series interlock connections and then use each one of these groups to energize a separate interposing relay. The contacts from these separate interposing relays are then connected in another series connection to energize the final control relay that controls the operation of the machine.
Whereas this method may provide sufficient control in some simple applications, other interlock systems require redundant controls and the ability to provide a means for self-checking the contacts to determine if they open and close properly. The present invention provides a self checking control system that addresses these and other problems.


An electronic device includes a housing with a carrier therein. The carrier includes a recess with a restricting portion therein. An access unit is disposed in the recess. An elastic member is connected to the access unit and engaged with the restricting portion to restrict the access unit in the recess. A fixed member is connected to the access unit. A movable member is movably disposed on the carrier, including a first contact portion and a second contact portion. When an external force is exerted on the movable member along a first direction, the first contact portion pushes the elastic member along the first direction to deform and separate from the restricting portion, and the second contact portion pushes the fixed member to move along a second direction perpendicular to the first direction, such that the access unit can be removed from the housing.

1. Field of the Invention
The present application relates to an electronic device, and in particular to a personal computer (PC) with an access unit capable of quick installation and uninstallation.
2. Description of the Related Art
Presently, the installation and uninstallation of an access unit, such as an optical disk drive (ODD) module or a hard disk drive (HDD) module to/from a personal computer (PC) are usually complicated. For example, to take apart an ODD module from a PC, the housing of the PC is first removed, and the connector jointed with the ODD module is removed. Consequently, the screws used for mounting the ODD module on a bracket in the PC are loosened, such that the ODD module can be drawn out of the PC. Conversely, to install the ODD module in the PC, the aforementioned procedures should be taken in reverse order.
It should be noted that the conventional installation and uninstallation procedures of the access unit have some disadvantages, such as being complicated, inflexible, and time consuming. Therefore, it may easily cause inconvenient operation for users and adversely affect the production efficiency and the manufacturing overhead (MOH) for the production lines.


A television event may be consumed after been stored in a mass memory of a multimedia unit, but still fully relies on the security of a secure device. A conversion of a received content aims at firstly descrambling the content using control words included in entitlement control messages and immediately re-encrypting the descrambled content by a unique key generated specifically for this content. Access conditions attached to the entitlement control message containing the control word are temporarily stored and once the decryption is terminated, the secure device produces an information block. This information block containing for example access conditions and an identifier of the content is either stored into a secure memory of the secure device or stored in the mass memory with the encrypted content. The unique key is made up of a combination of a root key specific to the secure device and the information block.

The development of storage on a hard disk has opened up new applications such as television broadcast storage and the preloading of films or other events proposed for purchase.
In a well known method, to be able to visualize a Pay-TV event, such as a film, a sports event or a game in particular, several streams are broadcast toward a multimedia unit, for example a decoder. In particular, these streams are on one hand the file of the event in the form of an encrypted data stream and on the other hand a control message stream allowing the decryption of the data stream. The content of the data stream is encrypted by at least one "control word" (CW) and more generally by control words that are renewed regularly. This second stream is called ECM stream (Entitlement Control Message) and can be formed in two different ways. According to a first method, the control words are encrypted by a key, called a transmission key TK that generally pertains to the transmission system between a management center and a security module associated with the receiver/decoder. The control word is obtained by decrypting the ECM control messages by means of the transmission key TK.
According to a second method, the ECM stream does not contain directly the encrypted control words, but rather contains data allowing the determination of the control words. This determination of the control words can be carried out by means of different operations, in particular by decrypting, this decryption being able to obtain the control word directly, which corresponds to the first method described above, but the decryption can also result to a piece of data which contains the control word, the latter must also be extracted from the data. In particular, the data can contain the control word as well as a value associated to the content to be broadcast and in particular the access conditions to this content. Another operation allowing the determination of the control word can use, for example, a one-way hashing function of this access conditions information in particular.
The security operations are generally carried out in a security module associated to the multimedia unit or to the decoder. This type of security module can be produced in particular according to four distinct forms. One of these is a microprocessor card, a smart card, or more generally an electronic module (in the form of a key, a badge, etc.). This type of module is generally removable and can be connected to the decoder. The form with electric contacts is the most widely used, but does not exclude a connection without contact for example ISO 14443.
A second known form is that of an integrated circuit shell placed, generally in a definitive and irremovable way in the decoder board. An alternative is made up of a circuit mounted on a base or a connector such as a SIM module connector.
In a third form, the security module is integrated into an integrated circuit shell that also has another function, for example in a descrambling module of the decoder or the microprocessor of the decoder.
In a fourth embodiment, the security module is not produced as hardware, but rather its function is implemented only in the software form. Given that in the four cases, although the security level differs, the function is identical, reference is made to a security module regardless of the way in which its function is carried out or the form that this module can take.
The user unit receiving the data stream and the message stream extracts the messages in order to transmit them to the security module. As the messages arrive at the same time as the data, the security module can transmit the active control word as early as this is necessary. According to the systems used, a control message can comprise more than one control word, for example two, so that the user unit constantly disposes of the current control word and of the following control word.
It is possible that in addition to the use of the event in broadcast mode, this same event is stored on the hard disk of the user unit for subsequent use. This process raises two problems, namely the definition of the access conditions and the renewal of the transmission key TK.
The first problem to arise concerns the management of the access to this content, namely that the conditions for one broadcast mode can be different to the conditions of a different mode. One solution is to multiply the access conditions in the control message as described in the document WO01/80563.
In order to resolve the second problem, it has been proposed to create a key safe on the hard disk to memorize the transmission key TK valid at the time of the transmission of the event (see WO03/079683).
The content distribution operators require a more flexible solution that offers the same advantages.
The document WO03/107665 describes a solution including the creation of an index list formed at the time of the reception of the content and the control messages. The control messages broadcast with the content are stored and subsequently re-used with the index file. In the case that the broadcast messages are not applicable for subsequent use, this document does not teach anything regarding how to solve this problem.
The document EP1215905 describes a solution in which the content is transmitted with a list containing the control word associated to each part of the content. This list contains an identifier allowing a link to be made between the content broadcast and the control words stored in the list. This list is prepared at a managing center and broadcast with the content to allow the synchronization of the control words and the content.
Document EP1187477 discloses a personal video recorder (PVR) which receives a broadcast data stream and encrypts data extracted from the stream before storing on a disk. The key used for the encryption is specific to each PVR and is preferably randomly generated.
Document: WO00/57636A1 discloses a set-top box which provides received content that satisfies the conditional access scheme to a descrambling and encrypting module via a coupling. The set-top box scrambles the content it passes to the module in order to prevent a malicious user from tapping into the signal passed between the set top box and module and inappropriately using the content. The module receives the scrambled content from set-top box and descrambles the content. The module knows the manner in which content from the set top box is scrambled and is thus able to de-scramble such content. In order to maintain the security of the de-scrambled content inside the system, the media content is also encrypted by the module. This encryption is based on a household identifier corresponding to a smart card. By so encrypting the media content, the content is tied to a particular household. In one implementation, all content is encrypted by the module. Alternatively, only content which is received in scrambled format may be encrypted, or some other indicator of which content to encrypt may be used (e.g., header information in the received content, pre-defined date and/or time ranges of content to be encrypted, etc.). By encrypting the media content using a smart card, and correspondingly requiring a smart card for decryption, limitations are placed on the ability to playback the content. This effectively creates a boundary to the user's network, the boundary being defined by wherever the smart card goes. This effective boundary prevents a malicious user from copying useable media content to a server on the Internet.

System and method to record encrypted content with access conditions


A novel electroconductive zinc oxide powder which comprises zinc oxide and, being present as a solid solution formed with the zinc oxide, 0.01 to 10 mass % relative to the zinc oxide of at least one element selected from the group consisting of IIIB Group elements, IVB Group elements and Fe, has an average primary particle diameter of 0.03 μm or less as calculated from its specific surface area, a bulk density of 0.20 g/ml or less and a volume resistivity of 1010 Ω·cm or less; and a method useful for producing the electroconductive zinc oxide powder. The zinc oxide powder exhibits distinguished dispersibility when incorporated into a rubber, a resin or the like as an electroconductivity imparting agent, and thus can provide a material having a reduced electric resistance.

Electroconductive zinc oxide is widely made practicable as an additive for imparting electroconductivity to paint, rubber, resin or the like. In the field of paint out of these, the paint workability thereof generally lowers when the viscosity of the paint becomes high; therefore, powder having a relatively large particle size is used in many cases so as not to make the paint viscosity high. On the other hand, in the field of rubber, resin or the like, the viscosity of the composition thereof is hardly worth consideration; therefore, electroconductive zinc oxide powder having a relatively small particle size is used.
And now, several processes have already been suggested as the process for producing an electroconductive zinc oxide powder. For example, JP-A-1-126228 discloses a process for stirring three components of zinc oxide, a water-soluble or water-dispersible aluminum compound, and ammonium carbonate or the like in an aqueous dispersion system in the presence of inorganic fine powder, filtrating and dehydrating the resultant, and then heating the dehydrated substance at a temperature of about 600° C. or lower in a non-oxidizing atmosphere, thereby producing an electroconductive zinc oxide fine powder which has an average particle size of approximately 0.1 μm and is excellent in transparency.
However, about conventional electroconductive zinc oxide powders, examples of which include one based on the above-mentioned process, the average primary particle size thereof is restricted to approximately 0.1 μm even if the particle size is made small. According to the particle size at such a level, a sufficient electroconductivity is not easily obtained by the addition of the electroconductive zinc oxide powder alone for the following reason: even if the powder is incorporated into a base material such as rubber or resin and uniformly dispersed therein, the zinc oxide particles are not brought into close contact with each other in the powder-incorporated composition.
If the particle size of electroconductive zinc oxide powder can be made into the form of superfine particles, which has a particle size that is one or more figures smaller than the present particle sizes, contact points between the particles can be increased by dispersing the superfine particles uniformly into a base material such as rubber or resin. As a result, a rubber composition or resin composition having a low resistance value would be obtained.
As another example of electroconductive zinc oxide in such a fine particle form, JP-A-10-236822 discloses a process of heating and aging a liquid mixture of a carboxylic acid zinc salt and an alcohol to produce a zinc oxide precursor, mixing this precursor with a metal hydroxide or a compound which is reactive with water to produce a metal hydroxide, distilling off the alcohol, and then firing the resultant. It is stated that this process makes it possible to yield a zinc oxide fine powder having an average particle size of about 0.001 to 1 μm.
JP-A-7-69631 discloses a process of adding a hexamethylenetetramine solution or a urea solution to a liquid mixture of a zinc salt and an aluminum salt; hydrolyzing the resultant at a pH of 5.5 to 7.5 to produce a flaky basic zinc-based coprecipitate; adding to the flaky coprecipitate a water-soluble compound of at least one element selected from the group consisting of antimony, indium, tin, zirconium and titanium to coat the surface of the flaky zinc coprecipitate; and then firing the resultant. It is stated that the zinc oxide obtained by this process has an average thickness of 0.1 to 2 μm, an average particle size of 1 to 100 μm, and an electric resistance of 1×103 Ω·cm or less.
As a process for producing zinc oxide in the form of fine particles which has a different use purpose but appears to have electroconductivity, JP-A-11-279525 discloses a doped electroconductive zinc oxide powder which (a) comprises at least one element selected from IIIB group elements and IVB group elements, wherein (b) the arithmetic average particle size in a given direction is from 3 to 100 nm in an electron microscopic projection image thereof, and (c) the total content of the IIIB group element(s) and the IVB group element(s) is from 1 to 15% by mole.
However, the inventors' investigation demonstrates that in the case of dispersing the zinc oxide powder produced by a conventional process as described above into a base material such as rubber or resin, the property of the base material can be maintained but a fall in the electric resistance value is insufficient or both of the base material property and the electric resistance value are insufficient in any case. Thus, it cannot be said that the purpose of the addition of the electroconductive zinc oxide powder can be sufficiently exhibited.
Paying attention to such a situation, the inventors have made the present invention. An object thereof is to provide an electroconductive zinc oxide powder having excellent dispersibility and electroconductivity-imparting property such that the incorporation of the powder into a base material such as rubber or resin causes a composition having a largely-decreased electric resistance value to be yielded without lowering the property of the base material; a process for the production thereof; and further an electroconductive composition wherein characteristics of the electroconductive zinc oxide powder are utilized to reform rubber or resin.

Electroconductive zinc oxide powder and method for production thereof, and electroconducitve composition


Three magnetically cooperating parts are movable relative to one another, one part being provided for connection to a drive shaft, one part being provided for connection to an output shaft, and one part being provided as a stationary part. A first part surrounds a second part, these parts having permanent magnets which alternately exhibit north poles and south poles along the circumference. The third part comprises a yoke surrounding the first part, which yoke serves as a magnetic return element, and which has magnetically conductive teeth at the inner side of the yoke.

The invention relates to a magnetic drive arrangement comprising at least three magnetically cooperating parts which are movable relative to one another, one part being provided for connection to a drive shaft, one part being provided for connection to an output shaft, and one part being provided as a stationary part, a first and a second part comprising permanent magnets which alternately exhibit north poles and south poles along the circumference, a third part having teeth of a magnetically conductive material for modulating the magnetic fields generated by the permanent magnets.
A magnetic drive arrangement of the type defined in the opening paragraph is known from EP 669 700, to which U.S. Pat. No. 5,633,555 corresponds. In this known drive arrangement the toothed third part is interposed as a central part between the first part and the second part. The individual teeth of this third part are interconnected by portions that must be very thin because otherwise they will short-circuit the magnetic flux generated by the magnet poles of the second part. The portions between the teeth of the third part are highly saturated in operation.
As a result of the requirement that the portions between the teeth of the third part must be thin, the third part can only be manufactured with a limited mechanical stability. This is a substantial drawback, particularly in the case of magnetic drive arrangements which serve to transmit larger torques.


Techniques are provided for performing hierarchical coding in a multi-antenna communication system (e.g., a SIMO, MISO, or MIMO system). At a transmitter, a base stream and an enhancement stream are coded and modulated separately to obtain first and second data symbol streams, respectively. The first data symbol stream is processed in accordance with a first spatial processing scheme (e.g., a transmit diversity or a spatial multiplexing scheme) to obtain a first set of symbol substreams. The second data symbol stream is processed in accordance with a second spatial processing scheme (e.g., transmit diversity or spatial multiplexing) to obtain a second set of symbol substreams. The first set of symbol substreams is combined (e.g., using time division multiplexing or superposition) with the second set of symbol substreams to obtain multiple transmit symbol streams for transmission from multiple transmit antennas. A receiver performs complementary processing to recover the base stream and enhancement stream.

Wireless communication systems are widely deployed to provide various communication services such as voice, packet data, broadcast, and so on. These systems may be capable of providing communication for multiple users simultaneously by sharing the available system resources. Some examples of such systems include code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, and frequency division multiple access (FDMA) systems.
A wireless communication system may provide broadcast service, which typically entails the transmission of broadcast data to users in a designated broadcast area instead of specific users. Since a broadcast transmission is intended to be received by multiple users within the broadcast area, the broadcast data rate is normally determined by the user with the worst channel conditions. Typically, the worst-case user is located far away from a transmitting base station and has a low signal-to-noise ratio (SNR).
The users in the broadcast area typically experience different channel conditions, achieve different SNRs, and are capable of receiving data at different data rates. Hierarchical transmission may then be used to improve broadcast service. With hierarchical transmission, the broadcast data is divided into a "base stream" and an "enhancement stream". The base stream is transmitted in a manner such that all users in the broadcast area can recover this stream. The enhancement stream is transmitted in a manner such that users experiencing better channel conditions can recover this stream. Hierarchical transmission is also referred to as hierarchical coding, where the term "coding" in this context refers to channel coding rather than data coding at the transmitter.
One conventional method of implementing hierarchical coding is through the use of non-uniform modulation. In this method, data for the base stream is modulated with a first modulation scheme and data for the enhancement stream is modulated with a second modulation scheme that is superimposed on the first modulation scheme. The first modulation scheme is typically a low-order modulation scheme such as QPSK, and the second modulation scheme may also be QPSK. In this case, the resultant modulated data for both streams may resemble 16-QAM modulated data. All users in the broadcast area are able to recover the base stream using QPSK demodulation. Users with better channel conditions are also able to recover the enhancement stream by removing the modulation due to the base stream. Hierarchical coding using non-uniform modulation is implemented by some conventional systems such as a Direct Video Broadcasting standard T (DVB-T) system.
Hierarchical coding is conventionally used for a single-input single-output (SISO) system. A SISO system employs a single antenna at a transmitter and a single antenna at a receiver. For the SISO system, hierarchical coding may be implemented, for example, using non-uniform modulation as described above.
A wireless communication system may employ multiple antennas at either the transmitter or the receiver, or at both the transmitter and receiver. The multiple antennas may be used to provide diversity against deleterious path effects and/or to improve transmission capacity, both of which are desirable. There is a need in the art for techniques to perform hierarchical coding with multiple antennas in a wireless communication system.

Hierarchical coding with multiple antennas in a wireless communication system


A computer-implemented technique for accessing textures by a graphics processing unit (GPU), includes determining a frequency with which a first texture is expected to be accessed by an application executing on a GPU, determining a frequency with which a second texture is expected to be accessed by an application executing on the GPU, determining to load memory address information associated with the first texture into a GPU register when the frequency is greater than or equal to a threshold frequency value, determining to load memory address information associated with the second texture into a buffer memory when the frequency is less than the threshold frequency value, receiving a draw call utilizing the texture, rendering the draw call using the first texture by accessing the memory address information in the GPU register, and the second texture by accessing the memory address information in the buffer memory.

The disclosed subject matter relates to the field of graphic processing. More specifically, but not by way of limitation, the disclosed subject matter relates to techniques for accessing textures by a graphics processor.
Computers and other computational devices typically have at least one programmable processing element that is generally known as a central processing unit (CPU). They frequently also have other programmable processors that are used for specialized processing of various types, such as graphic processing operations, which may be performed by graphic processing units (GPUs). GPUs generally comprise multiple cores or processing elements designed for executing the same instruction on parallel data streams, making GPUs more effective than general-purpose CPUs for algorithms in which processing of large blocks of data is done in parallel. In general, a CPU functions as the host and hands-off specialized parallel tasks to the GPUs.


An optically clear thermoplastic resin composition consisting essentially of: structural units derived at least one substituted or unsubstituted polycarbonate, at least greater than 30 weight percent of a substituted or unsubstituted polyester, a modified polycarbonate, an impact modifier having a refractive index in the range between about 1.51 and about 1.56 and an additive is disclosed. The composition possess good optical properties, flow, stability and mechanical property. Also disclosed is a process to prepare these compositions and articles therefrom.

This invention relates to an optically clear thermoplastic resin composition, a method to synthesize the composition and articles made from the compositions.
Polycarbonate is a useful engineering plastic for parts requiring clarity, high toughness, and, in some cases, good heat resistance. However, polycarbonate also has some important deficiencies, among them poor chemical and stress crack resistance, poor resistance to sterilization by gamma radiation, and poor processability. Blends of polyesters with polycarbonates provide thermoplastic compositions having improved properties over those based upon either of the single resins alone. Moreover, such blends are often more cost effective than polycarbonate alone. The miscibility of PC with the polyesters gives the blends the clarity needed, but this is restricted to (semi) aliphatic polyesters such as poly (cyclohexane dimethanol cyclohexane dicarboxylate) (PCCD) or a glycolized copolyester such as polyethylene glycol cyclohexane dimethanol terephthalate (PCTG).
U.S. Pat. Nos. 4,188,314, 4,125,572; 4,391,954; 4,786,692; 4,897,453, and 5,478,896 relate to blends of an aromatic polycarbonate and poly cyclohexane dimethanol phthalate. U.S. Pat. No. 4,125,572 relates to a blend of polycarbonate, polybutylene terephthalate (PBT) and an aliphatic/cycloaliphatic iso/terephthalate resin. U.S. Pat. No. 6,281,299 discloses a process for manufacturing transparent polyester/polycarbonate compositions, wherein the polyester is fed into the reactor after bisphenol A is polymerized to a polycarbonate. WO2004076541 describes thermoplastic composition based of a polycarbonate polymer with embedded polysiloxane domains having an average domain size between 20 and 45 nanometers or between 20 and 40 nanometers, which are translucent in nature.
Condensation copolymers having polysiloxane and polycarbonate blocks are known. Representative of such polymers are those disclosed by U.S. Pat. Nos. 4,681,922, 3,189,662, 3,419,635, and 3,832,419 have an elastomeric character and useful as adhesives, coatings, sealants, roofing material, impact modifying additives and the like. While U.S. Pat. No. 4,794,141 discloses molding compositions containing polydiorganosiloxane/polycarbonate block copolymers, elastomeric polymers. The elastomeric polymer is described as a hydrogenated block copolymer of a vinyl aromatic monomer and a conjugated diene.
A polymer blend comprising a polyalkylene terephthalate, an organopolysiloxane-polycarbonate block copolymer, and a halogenated copolycarbonate having improved impact, heat distortion and flame retardant properties is described in U.S. Pat. No. 4,155,898. U.S. Pat. Nos. 4,161,498; 4,155,898; and 4,161,469 describe polyalkylene terephthalate resin and all organopolysiloxane-poly-carbonate block copolymer having impact and heat distortion properties. U.S. Pat. No. 4,994,532 describes functionalized polydimethylsiloxane fluids which react with polycarbonate in the melt to form polydimethylsiloxane/polycarbonate block copolymers. The resultant copolymers are described as transparent and show improved flow. The U.S. Pat. No. 5,026,791 relates to an aromatic carbonate polymer having a siloxane Unit in the backbone of the polymer. U.S. patent application Ser. No. 10/882,529 disclose a transparent/translucent composition comprising 1 to 30 weight percent of a cycloaliphatic polyester and greater than or equal to 40 weight percent of a polyorganosiloxane/polycarbonate block copolymer, while U.S. patent application Ser. No. 10/373,547 teaches the compositions with polyesters with impact modifiers. However in the above compositions low temperature ductility is sacrificed for better flow and impact, and use of impact modifiers leads to a decrease in the transparency. The polymers of polycarbonate with the siloxane, while useful, have lower than desired flow properties, require high torque or high molding pressures during processing. The siloxane-carbonate polymers are also known to possess inadequate impact strength at low temperatures and inadequate resistance to distortion.
From the standpoint of ease of processing, it is desirable for a thermoplastic to have higher melt flow properties. There is a continuing need for polycarbonate polyester blends having a good balance of optical property, processability, solvent resistance and good mechanical and thermal properties.

Optically clear polycarbonate polyester compositions


A sealing ring, for use in establishing a fluid-tight connection between the facing ends of tubular members which are to be braced axially with respect to one another, comprises a thin sheet-metal ring provided with a corrugation which defines an effective sealing ring thickness greatly in excess of the thickness of the sheet-metal. The sealing ring is provided with a non-metallic coating on both sides, the coating on at least one side being a layer which functions to achieve microsealing.

(1) Field of the Invention
The present invention relates to the establishment of fluid-tight couplings between parts and, particularly, to sealing the joints between facing adjacent ends of conduits or the like. More specifically, this invention is directed to sealing rings and, especially, to compressible metal ring seals for use between parts which are to be braced axially with respect to one another. Accordingly, the general objects of the present invention are to provide novel and improved methods and articles of such character.
(2) Description of the Prior Art
Sealing rings for preventing leakage between facing surfaces which lie opposite to one another, and are axially braced with respect to one another, are well known in the art. Such sealing rings are, for example, widely used between lengths of pipe or the like which are to be joined in series by threaded coupling members, the coupling precluding relative axial movement between adjacent pipes. The characteristics of such sealing rings, i.e., the inner diameter, external diameter, thickness and material, for respective applications are typically found in published specifications such as, for example, DIN standards.
A long standing problem in the art is precipitated by the fact that sealing rings designed for the type of usage briefly described above are customarily relatively thick, the thickness being dictated by the desire to minimize the possibility of the rings becoming off-center as a consequence of slipping into threads or recesses in the coupling mechanism. Any such slippage, of course, will result in a portion of the ring extending into the passage carrying the fluid medium, thereby restricting flow and/or causing unacceptable turbulence. The seal ring thickness previously deemed necessary, however, usually leads to an unfavorable, and therefore undesirable, ratio of the compressed width of the ring to its thickness. This is particularly critical in the case of pipes or similar parts which are to be rotated, i.e., tilted axially, with respect to one another since, in such environments, the annular surfaces to be sealed do not reach a final position in which they are precisely parallel to one another or entirely in registration with one another. The sealing ring, accordingly, has to compensate for such lack of parallelism or registration throughout its entire service life.


The present invention generally relates to stabilization straps, and is more specifically concerned with a helmet stabilization strap apparatus. The stabilization strap apparatus provides connectors so configured and sized as to be mountable on the helmet, and each include a first pivotal interconnecting element and a first interlocking element. The stabilization strap apparatus further includes a strap member having ends connectable to a respective connector. Each of the ends includes a second pivotal interconnecting element and a second interlocking element, such that the second pivotal interconnecting element is mountable in a pivotal connection to the first pivotal interconnecting element and the second interlocking element matingly corresponds to the first interlocking element. Each ends of the strap member is pivotable around the pivotal connection and lockable at various strap positions with respect to the connectors when the second interlocking element engages the first interlocking element.

Conventional prior art safety helmets typically worn by users practicing activities requiring head protection, such as for example cyclists, are generally domed-shaped and come in various sizes and shapes. Fastening straps are also generally required to retain the helmet more securely in position on the wearer's head. These straps form a helmet retention system and are usually mounted to the helmet and extend under the chin of the helmet wearer.
These fastening straps assist in maintaining the helmet securely attached to the wearer's head. Indeed, not only do they minimize the occurrences of vertical movement of the helmet being projected off of the wearer's head, but they also generally help to minimize the occurrences where the helmet is pivoted off of the front or rear portion of the wearer's head.
However, such fastening straps may not always prevent a pivotal play toward the front of the wearer's head since the position of the straps holding the helmet extends under the chin. This potential pivotal play may result in exposing the back of the wearer's head, which may be hazardous during a multiple-impact fall.
In U.S. Pat. No. 5,704,072 issued in 1994 to Garneau and entitled "Occipital retention strap for cyclist headgear", the presented helmet is provided with an adjustable and removable retention strap assembly which contours the occipital portion of the wearer's head. This retention strap assembly mountable to the helmet using for example Velcro™. However, this retention strap assembly may not ensure the symmetry in positioning the strap with respect to the helmet and may not ensure the positioning repeatability of the strap to the helmet because no pre-determined attachment positions are defined on the Velcro™ area. Further, the retention strap assembly must generally be completely removed from the helmet to be repositioned at a specific location with respect to the helmet.

Adjustable stabilization strap apparatus


The inventive fabrication process for magnetoresistive devices (CPP-GMR devices) involves the formation of a zinc oxide or ZnO layer that provides the intermediate layer of a spacer layer, comprising Zn film formation operation for forming a zinc or Zn layer and Zn film oxidization operation for oxidizing the zinc film after the Zn film formation operation. The Zn film formation operation is implemented such that after a multilayer substrate having a multilayer structure before the formation of the Zn film is cooled down to the temperature range of −140° C. to −60° C., the formation of the Zn film is set off, and the Zn film oxidization operation is implemented such that after the completion of the Zn film oxidization operation, oxidization treatment is set off at the substrate temperature range of −120° C. to −40° C. Thus, excelling in both flatness and crystallizability, the ZnO layer makes sure the device has high MR ratios, and can further have an area resistivity AR best suited for the device.

1. Field of the Invention
The present invention relates generally to a fabrication process for magnetoresistive devices of the CPP type (or CPP structure) adapted to read the magnetic field intensity of magnetic recording media or the like as signals, and more particularly to a process for the formation of a spacer layer that is a part of an essential device component and has influences on device's performance. The magnetoresistive device of CPP structure, for instance, may be used with hard disk drive systems, MRAMs, and magnetic sensors.
2. Explanation of the Prior Art
In recent years, with an increase in the longitudinal recording density of magnetic disk systems, there have been growing demands for improvements in the performance of thin-film magnetic heads. For the thin-film magnetic head, a composite type thin-film magnetic head has been widely used, which has a structure wherein a reproducing head having a read-only magnetoresistive device (hereinafter often called the MR device for short) and a recording head having a write-only induction type magnetic device are stacked together.
The MR device, for instance, includes an AMR device making use of the anisotropic magnetoresistive effect, a GMR device harnessing the giant magnetoresistive effect, and a TMR device tapping the tunnel-type magnetoresistive effect.
The reproducing head must have some characteristics in general, and high sensitivity and high output in particular. For the reproducing head capable of meeting such demands, there has already been a GMR head mass produced that makes use of a spin valve type of GRM device.
Such a spin valve type GMR device typically comprises, as part of the device, a spacer layer, a first magnetic layer (the so-called free layer) formed on one surface of the spacer layer, a second magnetic layer (fixed magnetization layer) formed on another surface of the spacer layer, and a pinning layer (generally an antiferromagnetic layer) formed in contact with the fixed magnetization layer that faces away from the spacer layer.
The free layer operates such that the direction of magnetization changes in response to a signal magnetic filed coming from outside, and the fixed magnetization layer has the direction of magnetization fixed by an exchange coupling magnetic field from the pinning layer (antiferromagnetic layer). With such device structure, MR changes are achievable via a difference in the relative angle of spins in two such ferromagnetic layers.
The structure of the spacer layer sandwiched between the first magnetic layer (the so-called free layer) and the second magnetic layer (the fixed magnetization layer) could be an imperative site that determines whether MR characteristics are good or bad. Applicant has already filed JP(A)2008-91842, proposing a specific multilayer structure best suited for the spacer layer. More specifically, Applicant discloses that the spacer layer is built up of a triple-layer structure comprising a first nonmagnetic metal layer and a second nonmagnetic metal layer, each one formed of a nonmagnetic metal material, and a ZnO semiconductor layer interposed between the first and the second nonmagnetic metal layer.
With the characteristics of the magnetoresistive device in mind, it would go without saying that of importance is what material is selected from the first and the second nonmagnetic metal layer. Yet, to allow the MR characteristics to work well, it has now turned out according to Inventors' intensive studies that another vital point is the method of forming the ZnO semiconductor layer that becomes the intermediate layer of the spacer layer, i.e., how to form that ZnO semiconductor layer. In particular, Zn has a melting point of as low as 420° C., and is more evaporable at lower temperatures in reduced pressure. For this reason, care must be taken of handling operation indigenous to Zn to which no attention has been paid so far.
Among prior arts that would appear to be relevant to the present invention, there is the one set forth in JP(A)2001-203408. The publication discloses a technique for forming an Al film while a substrate is being, or has been, cooled down. The publication states that the obtained Al film naturally oxidizes into an Al2O3 film; however, nowhere is any specific oxidization condition referred to. That Al2O3 film is quite different from ZnO, to which the fabrication process of the invention is to be applied, in terms of compound. Furthermore, the Al2O3 film disclosed in JP(A)2001-203408 should preferably be in an amorphous film structure form, whereas the ZnO film, to which the present invention is to be applied, should preferably have a film structure of good crystallizability: there is a sheer difference in the film characteristics demanded for both.
The situations being like this, the present invention has been made for the purpose of, with how to form the ZnO film in the spacer layer in mind, providing a fabrication process for magnetoresistive devices, which can not only achieve high MR ratios but have an area resistivity (AR) best suited for device fabrication as well. In terms of ideal morphology, the ZnO film should excel in both flatness and crystallizability.

Fabrication process for magnetoresistive devices of the CPP type


A method of forming poly-silicon thin film transistors is described. An amorphous silicon thin film transistor is formed on a substrate, and then the Infrared (IR) heating process is used. A gate metal and source/drain metal are heated rapidly, and conduct heat energy to an amorphous silicon layer. Next, crystallization occurs in the amorphous silicon layer to form poly-silicon. Therefore a poly-silicon thin film transistor is produced.

Thin film transistors (TFT) have generally been used as devices for active matrix liquid crystal displays (AMLCD). The thin film transistors usually have two types of amorphous silicon (a-Si) and poly-silicon (poly-Si) for different silicon films. The mobility of an a-Si TFT is only about 0.5–1 cm2/V-s, but a poly-Si TFT has much higher mobility for better crystal character and fewer crystal defects in poly-Si. Therefore, displays fabricated from poly-Si TFT have advantages of high response speed, high resolution, and integrated driver circuits.
There are some drawbacks such as lower product yield, complex processes, and high process cost existing in the poly-Si TFT fabrication. In contrast, a-Si TFTs are mainly fabricated for displays with a lower process cost and well-developed techniques.
Owing to the bottleneck of crystallization techniques, the poly-Si TFT is still not the market mainstream; the conventional methods for fabricating poly-Si films are solid phase crystallization (SPC), excimer laser annealing (ELA), and metal induced lateral crystallization (MILC). SPC is not applicable to flat panel display fabrication because the upper limit temperature of a glass substrate is 650° C., while ELA has drawbacks of the high cost for laser light, process stability, and poor crystal uniformity. Besides, MILC may have problems in metal diffusion. Therefore, present poly-Si forming methods have technical problems and higher production cost for more complex processes. So the poly-Si TFT is still unable to compete with the a-Si TFT.
Further, because the technical problems in poly-Si films fabrication have not been overcome, some manufacturing difficulties exist if the poly-Si TFT fabrication present is utilized to develop large-size displays.

Method of forming poly-silicon thin film transistors

Industrial Technology Research Institute


A method and apparatus for displaying text which efficiently couples information derived from the parse tree for the text with the display of the text. Use of parse tree information allows the system to display different parts of the text in a context-sensitive manner. The method involves creating a parse array from a parse tree for the text. The parse array contains a compressed representation of the nodes of the parse tree. This parse array is used to find the parse node which corresponds to a particular location in the text. The parse array can be traversed to a chosen character using a stack. In one embodiment the stack can be saved periodically to improve performance so that the parse node corresponding to a character can be more quickly determined. The parse array is also used to find the entire portion of the text which corresponds to the parse node. The text corresponding to a particular parse node is displayed with a display characteristic which differentiates this portion of the text from the remainder of the text. Thus, a user of this display can view the text in a context-sensitive fashion.

1. Field of Invention
This invention relates to the field of context sensitive text displays. In particular, this invention relates to determining the display characteristics of text efficiently from the parse node containing the text in a parse derived from the text.
2. Description of Background Art
Computers have long been used to display text to humans to facilitate editing and understanding. Typically, a human using a computer to manipulate or view a block of text. For purposes of illustration, a block of text will be assumed to be simply an array of characters.
In a modern computer text editor or text display tool, displaying text on a computer screen involves several steps. First, the tool needs to identify where in the text array the display should begin. This amounts to having an integer that indicates the starting position in the array. This information can be provided to the tool from the human being by keystrokes indicating a line number or a scroll bar indicating the relative position in the file. Next, the tool needs to "paint" the screen with the characters. Conceptually, the tool gets a character at the indexed point, determines the screen display characteristics, such as color, font, size, or format, associated with that character at that point in the text array, and provides that information to the graphical display hardware. The computer then increments the index and repeats the process with the next character.
Conventional text editors require the user to specify the display characteristics associated with particular points in the text without regard to what the particular text is or "means." However, in certain applications, the text may have context that the computer could use to determine the display characteristics. For example, computer programs are written in computer languages like C, Pascal, or Cobol. A program written in computer language has text strings within it that have a particular meaning or significance, such as keywords like "if", "else", or "while". A more sophisticated text display tool could use this context-sensitive information within the text to define the display characteristics of the text. Borland's C++ development environment for DOS machines provides a text editor that, for example, displays keywords with one color and comments in another color.
Using the context of the text to determine the display characteristics presents computational performance problems. The user wants to see the text displayed on the computer screen displayed promptly. However, setting the display characteristics as a function of the context requires that the computer compute the context. That computation can be done at the time the display is requested, or, alternatively, the context computation could be performed at some other, earlier time and the result stored. At the time the display is requested, the computer has to perform some computation either directly or by finding a previous result. This computation takes time. If this time is too long, then the text will not be displayed promptly, thus frustrating the user. Economically viable context-sensitive text displays therefore must efficiently store and compute the context.
A review of the process of extracting context out of certain kinds of text will clarify the problems a context-sensitive display has. One place that context extraction occurs is in the process of generating executable machine code from the text of a computer program written in a high level language. This process is called compilation. Compilation involves several steps: lexical analysis, parsing, code generation, and optimization. Only lexical analysis and parsing are relevant for purposes of displaying context sensitive information Lexical analysis involves breaking the text into distinct, non-overlapping text strings in accordance with the rules of a specified language. These non-overlapping objects are referred to as tokens. The lexical analyzer can characterize some of these text strings because the text matches a keyword, or is a number or a symbol such as "&". Lexical analysis is computationally fast because it relies only on "local" information to determine where the next token begins and ends.
After the lexical analyzer breaks the text into tokens, a parser converts the entire sequence of tokens into a parse tree that describes the computer program's structure. From this parse tree, the code generator can create blocks of executable code corresponding to the nodes of the parse tree. The code generator can then link the blocks together to make an executable program. An optimizer can then look for improvements to make in each block to reduce the amount of memory required to store the executable code or to decrease the run time of the executable code. The nature and mathematical structure of compilers is described in Compilers Principles, Techniques and Tools, by Alfred Aho, Ravi Sethi, and Jeffrey Ullman, 1986, ISBN 0-201-10088-6 which is hereby incorporated by reference. The steps for building a compiler are shown in Introduction to Compiler Construction with UNIX by Axel T. Schreiner and H. George Friedman, Jr., published by Prentice-Hall, 1985, ISBN 0-13-474396-2, which is hereby incorporated by reference.
If it is only desired to modify the display characteristics of the text depending solely on information that can be obtained "locally" from a lexical analyzer, then a text display tool can perform lexical analysis at the time it scans the text for the display. For common computer languages, this would allow the display tool to paint different keywords in different colors without a noticeable performance problem. However, this may not produce enough information for the user.
Changing the display characteristics of the text in accordance with information associated with the corresponding parts of a parse tree can be very useful. However, because constructing a parse tree requires processing all of the text, a tool using the parse tree to determine the display characteristics of the text will probably not be able to compute the entire parse tree every time the display needs to be changed. Therefore, such a display tool will generally require that the parse tree be generated once and stored, and then accessed when the need arises. However, conventional parse trees occupy significant amounts of memory, and require a substantial amount of time to build.
The memory requirements of a conventional parse tree are straight-forward to compute. Consider a text block consisting of N characters. Experience has shown that a file of N characters will generate a parse tree with N/4 nodes. A conventional parse tree which has nodes with a data structure written in C could be declared as follows:
______________________________________ typedef tree.sub.-- nod.sub.-- struct { struct pt.sub.-- node.sub.-- struct *parent, **children; int child.sub.-- count; char *start.sub.-- position, *end.sub.-- position; int parse.sub.-- tree.sub.-- id; /* other stuff*/ } tree.sub.-- node.sub.-- struct, *pt.sub.-- node; ______________________________________
This data structure provides a pointer to the parent node, a pointer to an array of pointers to the children of the node, an integer for counting the number of children, pointers for indicating where, in the text block, the text that generated this node begins and ends, and an integer to indicate what number node this is. In a conventional, 32 bit machine, each node will require one word for the parent pointer, one word to point at the array of children, one word for the child.sub.-- count, one word each for start.sub.-- position and end.sub.-- position, and one word for parse.sub.-- tree.sub.-- id. In addition, each node will require an additional word in its parent's array of children. Therefore, each parse node will require 7 words of memory. Therefore, this conventional tree structure will require 7N/4 words to store the parse tree for an N character file. In a conventional machine, there are 4 bytes per word, thus making the conventional data structure consume 7N bytes.

Method and apparatus for displaying text including context sensitive information derived from parse tree