text
stringlengths 2
806k
| meta
dict |
|---|---|
1. Field of the Invention
The present invention relates to a developing device structure employed for an electrophotographic recording apparatus such as a printer, a copier, etc.
2. Description of the Related Art
A developing device of this type is disclosed in the EPC Publication No. 0435259A3 filed by the present applicant.
In this developing device, a toner is supplied from a toner cartridge to a developing portion to be collected in a toner hopper portion, and is stirred by a stirring means provided in the toner hopper portion. Thereafter the toner is supplied to a photoconductor drum via a supply roller and developing roller.
In some electrophotographic recording apparatus, an indicator for positioning the printing paper is set at the central portion of the printing paper in the width direction thereof. Such an electrophotographic recording apparatus has typically a stirring means for the developing device as illustrated in FIG. 20.
A toner hopper stirring means 80 comprises a shaft 19 and helical members 81a and 81b respectively formed of springs. The helical members 81a and 81b have the same coil diameters and the same winding pitches. The helical members 81a and 81b are wound around the shaft in the directions opposite to each other. When the shaft 19 of the toner hopper stirring means 80 is turned in the direction of the arrow C, the toner positioned at both ends of the shaft 19 is stirred and moved toward the central portion of the shaft 19. If the feeding standard of the electrophotographic recording apparatus is set at the central portion of the printing papers, the printing frequency is increased at the central portion of the photoconductor drum when printing is performed on printing papers having different sizes, so that much toner is consumed at the central portion of the toner hopper portion in the developing device but is supplemented with the toner which is moved toward the central portion of the toner hopper portion by the toner hopper stirring means 80.
However, in the conventional developing apparatus, the toner collected in the toner hopper portion is always conveyed by the toner hopper stirring means toward the central portion of the toner hopper portion at a constant speed and supplied to the supply roller of the developing portion.
Accordingly, there is no problem when the amount of toner collected in the toner hopper portion is enough to sufficiently cover the toner hopper portion but there arises the problem that the toner is locally positioned at the central portion of the toner hopper portion and is reduced at both ends of the toner is hopper portion when the amount of toner reduced to such an extent that it does not sufficiently cover the toner hopper stirring portion. If printing is performed in the latter case, there is a problem that a printing irregularity occurs on the printing paper, which deteriorates the printing quality. Especially, if printing few characters on a printing paper continues, the printing quality is remarkably deteriorated.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
FIG. 1 depicts an air-bearing surface (ABS) view of a conventional magnetic recording transducer 10. The magnetic recording transducer 10 may be a perpendicular magnetic recording (PMR) head. The conventional transducer 10 includes an underlayer 12, side gap 14, side shields 16, top gap 17, optional top, or trailing, shield 18 and main pole 20.
The main pole 20 resides on an underlayer 12 and includes sidewalls 22 and 24. The sidewalls 22 and 24 of the conventional main pole 20 form an angle with the down track direction at the ABS. The side shields 16 are separated from the main pole 20 by a side gap 14. The side shields 16 extend at least from the top of the main pole 20 to the bottom of the main pole 20. The side shields 16 also extend a distance back from the ABS.
Although the conventional transducer 10 functions, methods of improving performance and fabrication of the transducer 10 are desired.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to a process for the preparation of aminoketones useful as central muscle relaxants. This invention is also concerned with a process for the preparation of intermediates for the aminoketones.
More specifically, the present invention pertains to a process for preparing a compound of the following formula [VI]: ##STR1## by oxidizing a compound of the following formula [I]: ##STR2## to obtain a compound of the following formula [IV]: ##STR3## and then forming the compound of the formula [VI] from the compound of the formula [IV]. The substituents R, R.sub.1, R.sub.2, R.sub.6 and R.sub.7 will be defined herein. Compounds of the formula [VI] are novel compounds and are useful as central muscle relaxants.
2. Description of the Related Art
It is generally known to use a heavy metal such as chromic acid as an oxidizing agent upon preparation of a ketone from a secondary alcohol. Such heavy metals are however noxious from biological and other standpoints, so that their use in the production of pharmaceutical products is not preferred.
Some processes which use an oxidizing agent other than heavy metals have hence been proposed, including the process using sodium hypochlorite and a phase transfer catalyst in combination [Lee, G. A., et al., Tetrahedron Letters, 1641 (1976)] and the process in which calcium hypochlorite is used in the presence of an acidic solvent such as acetic acid [Nwavkwa, S. D., et al., Tetrahedron Letters, 35 (1982)]. These oxidizing processes were however unable to prepare a ketone of the formula [IV] from an alcohol of the formula [I].
As a still further process for preparing an aminoketone from a ketone, it has been known to react the ketone with paraformaldehyde and an amine hydrochloride in the presence of concentrated hydrochloric acid in an alcoholic solvent (Japanese Patent Application Laid-Open No. 119444/1988). In the aminoketone prepared by this process, the amine moiety is however in its hydrochloride form. It is therefore necessary to convert the reaction product to the free aminoketone by neutralizing it with a suitable alkali agent, for example, aqueous ammonia or an aqueous solution of sodium hydroxide. The above process hence cannot avoid inconvenience such as higher production cost and complicated production steps.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The invention lies in the field of integrated technology and relates, more specifically, to an integrated circuit configuration, that is to say a circuit configuration which is arranged in a substrate, with at least one capacitor.
An integrated circuit configuration of this type is described, for example, in European patent EP 0 415 530 B1 (see U.S. Pat. Nos. 5,126,810 and 5,196,365). The integrated circuit configuration is a memory cell arrangement wherein a memory cell comprises a transistor and a capacitor. The capacitor is embodied as a stacked capacitor and comprises a polysilicon structure with a plurality of polysilicon layers which are essentially arranged parallel one above the other and are connected to one another via at least one lateral support. The polysilicon structure is formed by the alternate deposition of polysilicon layers and SiO2 layers, which can be etched selectively with respect thereto, on the surface of the substrate, patterning of the sidewall, production of layers coverings (spacers) made of polysilicon on at least one sidewall of the layer structure and selective etching-out of the SiO2 layers. The polysilicon structure acts as a first capacitor electrode of the capacitor. The areas of the polysilicon structure are provided with a capacitor dielectric. Afterward, a second capacitor electrode of the capacitor is produced, which adjoins the capacitor dielectric. Despite the capacitor having a small space requirement, that is to say the capacitor having a small area when projected onto the substrate surface, the capacitor has a large capacitance since the surface area of the polysilicon structure is very large on account of the layers that are arranged one above the other.
It is accordingly an object of the invention to provide a method for fabricating an integrated circuit configuration with at least one capacitor which overcomes the above-mentioned disadvantages of the heretofore-known devices and methods of this general type and which, in comparison with the prior art, can have a smaller space requirement yet a high capacitance at the same time. With the foregoing and other objects in view there is provided, in accordance with the invention, a method of producing an integrated circuit configuration with at least one capacitor, which comprises:
providing a substrate having a surface defining a y-axis extending substantially perpendicular to the surface and defining a first height, a second height above the first height, and a third height between the first height and the second height;
producing a central part of a first capacitor electrode of the capacitor to extend from the first height to the second height, by forming a depression in an auxiliary layer applied on the substrate and filling the depression at least partly with conductive material;
after producing the central part, etching the auxiliary layer no deeper than to the third height;
producing a component of the integrated circuit configuration and connecting the component to the central part produced thereabove;
producing a spacer reaching at most to the second height, by depositing and etching back material as part of a spacing means, on uncovered parts of lateral areas of the central part;
growing conductive material, by selective epitaxy, on the central part but not on the spacing means;
depositing further conductive material substantially conformally;
etching back the conductive material to thereby produce from the conductive material
at least one side part of the first capacitor electrode beside the central part and spaced apart from the central part, such that the side part extends from the third height to the second height;
an upper part of the first capacitor electrode on the side part and the central part and connecting the side part and the central part to one another; and
to partly uncover a portion of the spacing means that projects laterally below the side part;
providing the first capacitor electrode with a capacitor dielectric; and
producing a second capacitor electrode adjoining the capacitor dielectric.
The resulting product is an integrated circuit configuration with at least one capacitor wherein the capacitor is arranged above a surface of a substrate. A y-axis runs perpendicularly to the surface of the substrate. A first capacitor electrode of the capacitor has a central part, which extends from a first height as far as a second height situated above the latter, with respect to the y-axis. The central part is connected to a componentxe2x80x94arranged below itxe2x80x94of the integrated circuit configuration. The first capacitor electrode has at least one side part, which is arranged beside the central part and is spaced apart from the latter. The side part extends from a third height, which lies between the first height and the second height, as far as the second height. The first capacitor electrode has an upper part which is arranged on the side part and the central part and connects these to one another. The first capacitor electrode is provided with a capacitor dielectric. A second capacitor electrode adjoins the capacitor dielectric.
The method may also be summarized as follows: The capacitor is produced above a surface of a substrate. A central part of a first capacitor electrode of the capacitor is produced in such a way that it extends from a first height as far as a second height situated above the latter, with respect to the y-axis. A component of the integrated circuit configuration is produced and is connected to the central part produced above it. At least one side part of the first capacitor electrode is produced in such a way that it is arranged beside the central part and is spaced apart from the latter. The side part is produced in such a way that it extends from a third height which lies between the first height and the second height, as far as the second height. An upper part of the first capacitor electrode is produced in such a way that it is arranged on the side part and the central part and connects these to one another. The first capacitor electrode is provided with a capacitor dielectric. A second capacitor electrode is produced in such a way that it adjoins the capacitor dielectric.
Since the capacitor dielectric covers all the areas of the first capacitor electrode starting at least from the third height, and the second capacitor electrode covers the capacitor dielectric, a part of the second capacitor electrode is also arranged between the lateral part and the central part.
As a result of the cutout in the first capacitor electrode between the central part and the side part, the surface of the first capacitor electrode, which greatly influences the capacitance of the capacitor, is enlarged primarily by lateral areas of the side part and of the central part in comparison with a capacitor electrode without a cutout, without the space requirement of the capacitor being increased. The larger the distance between the third height and the first height, the larger the capacitance of the capacitor.
A particularly large capacitance of the capacitor is obtained if the third height is nearer to the first height than to the second height.
The first capacitor electrode can be produced for example with the aid of a spacing means. To that end, an auxiliary layer is produced above the substrate. The central part is produced by producing a depression in the auxiliary layer and filling it with conductive material. The spacing means is formed in such a way that it adjoins lateral areas of the central part and projects laterally away from the central part below the third height. The upper part and the side part are produced in such a way that they adjoin the spacing means. The upper part adjoins the spacing means from above, while the side part laterally adjoins the spacing means and also adjoins from above the part of the spacing means which projects laterally away from the central part below the third height. The part of the spacing means which adjoins the lateral areas of the central part is consequently arranged between the central part and the side part, while the part of the spacing means which projects laterally away from the central part below the third height is arranged below the side part and can project laterally below the side part. Since this part is not covered by the side part at least laterally and possibly also partly from above, the spacing means can be removed by isotropic etching selectively with respect to the first capacitor electrode. The capacitor dielectric and the second capacitor electrode are subsequently produced.
In order to reduce the space requirement of the capacitor it is advantageous to produce the part of the spacing means which adjoins the lateral areas of the central part with a particularly small horizontal thickness. The horizontal thickness of this part of the spacing means is preferably homogeneous, that is to say that this part of the spacing means has the same thickness everywhere.
In order to reduce the space requirement of the capacitor, it is advantageous to produce the central part and the side part in such a way that their lateral areas are essentially parallel to the y-axis.
Given a homogeneous horizontal thickness of the part of the spacing means which adjoins the lateral areas of the central part, the lateral areas of the side part which face the central part follow the course of the lateral areas of the central part at an essentially constant distance from the lateral areas of the central part. Specifically, said distance is equal to the horizontal thickness of the spacing means.
A particularly large capacitance is obtained if the side part laterally surrounds the central part.
However, it is also possible to provide, say, two side parts which do not adjoin one another.
It is possible to provide more than one side part, which are at different distances from the central part. Each of the side parts may laterally surround the central part. A first side part which is arranged further away from the central part than a second side part also laterally surrounds the second side part. The side parts are interleaved in one another.
A first method is described below, wherein a spacing means is used whose part which adjoins the lateral areas of the central part has a homogeneous horizontal thickness.
After the production of the central part, the auxiliary layer is etched no deeper than as far as the third height. By depositing and etching back material, as part of the spacing means, a spacer is produced on uncovered parts of the lateral areas of the central part. The spacer reaches at most as far as the second height, so that at least one upper horizontal area of the central part is uncovered. The part of the spacing means which is produced as a spacer consequently adjoins the lateral areas of the central part and has an essentially homogeneous horizontal thickness. Material below the third height serves as a further part of the spacing means. Afterward, conductive material is grown by selective epitaxy in such a way that the conductive material grows on the central part but not on the spacing means. Further conductive material is deposited and subsequently etched back, so that the upper part is produced from the epitaxially grown conductive material and the side part is produced from the deposited conductive material, and the part of the spacing means which projects laterally below the side part is uncovered. Since the conductive material on the upper area of the central part is particularly thick on account of the selective epitaxy, conductive material, which can essentially form the upper part, remains on the central part during the etching back until the spacing means is uncovered.
The material from which the part of the spacing means which is produced as a spacer is produced can be etched back further than the thickness to which the material is deposited. In this case, upper regions of the lateral areas of the central part on which the conductive material can grow are also uncovered. During the etching back of the material, the material which is arranged below the third height, i.e. below the removed part of the auxiliary layer, can also be attacked. This is the case in particular when the same material is involved. Since the side part is to be arranged on the spacing means and the side part extends upward from the third height, the third height is defined by the depth to which the auxiliary layer is etched and the extent to which the material of the spacer is etched back.
By way of example, tungsten or tungsten silicide is suitable as conductive material if the central part is likewise composed of tungsten or tungsten silicide. However, any conductive material which grows on the central part but not on the spacing means is suitable.
The spacing means is composed, for example, of silicon nitride or of SiO2.
A particularly small space requirement of the capacitor is obtained if the depression is produced with the aid of a mask whose opening has dimensions which correspond to the minimum feature size F that can be fabricated in the technology used. Consequently, the central part produced by filling the depression also has a width and/or a length corresponding to the feature size F.
An even smaller space requirement can be obtained if, after the etching of the auxiliary layer, the central part is narrowed by isotropic etching. In this case the width and/or the length of the central part may even be smaller than the feature size F.
As an alternative, the mask used for the depression can be enlarged by spacers, so that the opening of the mask has dimensions which are smaller than the feature size F. In this case, the central part has particularly small horizontal dimensions even without isotropic etching.
Since such a central part has a horizontal cross section which is smaller than F2, the entire capacitor can have a space requirement of only F2.
In order to produce such an enlarged mask, material is deposited and etched back after the production of the mask with the aid of photolithographic process steps, with the result that spacers are produced in the opening of the mask, which spacers enlarge the mask, that is to say narrow the opening. As an alternative, it is possible to fabricate an opening with a smaller cross section than F2 using CARL (chemical amplification of resist lines). In this case, the mask is enlarged by silylation.
If more than one side part is to be produced, then after the production of the side part, a further spacing means can be produced analogously to the spacing means. The further spacing means laterally adjoins the side part. Afterward, conductive material is grown again by means of selective epitaxy, thereby enlarging the upper part. As in the production of the side part, further conductive material is deposited and etched back, thereby producing a further side part. This sequence of process steps can be repeated to produce additional side parts.
A second possibility for producing an integrated circuit configuration with at least one capacitor is described below, wherein a spacing means is used whose part which adjoins the lateral areas of the central part has a homogeneous horizontal thickness.
A further auxiliary layer is produced on the auxiliary layer. The depression cuts through the further auxiliary layer. After the production of the depression, the further auxiliary layer is etched isotropically, thereby extending the depression in the region of the further auxiliary layer. By filling the depression with the conductive material, the central part is produced in the region of the auxiliary layer and a part of the upper part is produced in the region of the further auxiliary layer. The upper part is thus arranged on the central part and projects beyond the central part laterally in all directions. The further auxiliary layer and the auxiliary layer are etched selectively with respect to the part of the upper part anisotropically as far as the third height, so that at least one part of the spacing means is formed from the auxiliary layer below the part of the upper part. This part of the spacing means consequently adjoins the lateral areas of the central part and has an essentially homogeneous horizontal thickness on account of the production of the part of the upper part with the aid of isotropic etching. The side part and a residual part of the upper part are subsequently produced in the form of a spacer by depositing and etching back material, parts of the spacer which laterally adjoin the part of the upper part and lie at the same height as the part of the upper part forming the residual part of the upper part.
The spacing means is produced in a self-aligned manner that is to say without a mask to be aligned, below the upper part and adjoining the central part. The distance between the edge of the non-extended depression and the edge of the extended depression determines the thickness of the part of the spacing means, which adjoins the lateral areas of the central part. Since the isotropic etching of the further auxiliary layer removes material uniformly proceeding from the original depression, the thickness of the spacing means is homogeneous. The further auxiliary layer can be dispensed with if, for the purpose of filling the depression, conductive material is deposited and is subsequently patterned with the aid of a mask in such a way that conductive material likewise remains on the auxiliary layer around the central part and forms the part of the upper part. In this case, on account of alignment inaccuracies of the mask, a homogeneous horizontal thickness of the part of the spacing means cannot be guaranteed. In order that the part of the upper part can be produced with essentially perpendicular edges, it is advantageous to produce on the further auxiliary layer a mask layer, which is cut through by the depression. The mask layer is removed only after the isotropic etching of the further auxiliary layer and before the filling of the depression. This also has the advantage that the thickness of the upper part is determined by the thickness of the further auxiliary layer. If the mask layer is dispensed with, then a thicker further auxiliary layer must be deposited in order to obtain the same thickness of the upper part, since the auxiliary layer is also eroded from above during the isotropic etching.
The following method is suitable in particular for producing a plurality of side parts:
The depression is produced in the auxiliary layer in such a way that it initially reaches as far as the third height. A surface of the auxiliary layer lies higher than the first height. Afterward, layers made alternately of conductive material and of insulating material are deposited, without filling the depression, and etched back. Side parts are produced by the etching back of the conductive material and parts of spacing means are produced by the etching back of the insulating material. The number of layers made of conductive material is equal to the number of side parts produced. A part of the bottom of the depression which is uncovered after the etching back of the last layer made of insulating material is subsequently etched more deeply at least as far as the first height. The as yet unfilled part of the depression is filled with conductive material by depositing conductive material and etching it back as far as above the first height. Conductive material which is surrounded by the innermost spacing means forms the central part. Conductive material which is arranged on the side parts, the spacing means and the central part forms the upper part. Preferably, layers deposited later are etched back further than layers deposited previously, in order that there is better contact between the upper part and the side parts.
By way of example, a part of the auxiliary layer is suitable as a part of the spacing means which projects laterally away from the central part.
In order to accurately set the etching depth when etching the auxiliary layer, it is advantageous to produce above the substrate a stop layer whose upper area lies in the region of the third height and to produce the auxiliary layer above that. The depression cuts through the stop layer. The part of the spacing means which projects laterally away from the central part is consequently the stop layer. The stop layer acts as an etching stop during the etching of the auxiliary layer. The stop layer can also act as an etching stop during the etching back of the material of the side part. In this case, an upper area of the stop layer lies at the third height.
The stop layer, the part of the spacing means which adjoins the lateral areas of the central part and the auxiliary layer are composed, for example, of silicon nitride or SiO2. In order to enable selective etching, it is advantageous if the stop layer is composed of a different material than the auxiliary layer.
The integrated circuit configuration may be a DRAM cell arrangement. By way of example, the component is a transistor which, together with the capacitor, forms a memory cell.
A particularly high packing density of the DRAM cell arrangement can be achieved if the capacitors of memory cells are arranged in rows and columns. In order that the side parts which, considered in vertical cross section, are arranged between the central parts have more space, it is advantageous to produce the central part in such a way that a width of the central part which is parallel to the direction of the rows is smaller than a distance between adjacent central parts of capacitors which are adjacent to one another along the rows. Correspondingly, a length of the central part which is parallel to the direction of the columns is preferably smaller than a distance between central part of capacitors which are adjacent to one another along the columns.
A horizontal cross section of the central part may be, for example, rectangular, in particular square, or circular.
The length or width of the central part may be smaller than the feature size F. For the case of the circular cross section, the width or the length of the central part is the diameter of the cross section. The space requirement per memory cell may be 4F2.
Other features which are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a integrated circuit configuration with at least one capacitor and method for fabricating it, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention relates to the field of knowledge-based expert systems. Knowledge-based expert systems are computer systems which perform reasoning by using inference engine, knowledge base (KB), and requested data. They perform reasoning in the same manner as human experts, because human experts' knowledge is stored in the knowledge base. Different tasks need different knowledge bases which are created by experts in different domains. Currently, most knowledge-based expert systems are created by using knowledge engineering tools, commonly called expert system shells.
Expert system shells simplify the process of building expert systems. In most of current expert system shells, the inference engine is built-in. Building an expert system in any domain is reduced to building a knowledge base in the specific domain.
The build-in inference engine is a computer program written by C, Ada, Lisp, Prolog, or other programming languages. It can reason the knowledge base created in a required format. Currently, there are three types of knowledge bases:
1. Rule-based: A set of `if-then` rules; PA1 2. Frame-based: Structured facts and relations; and PA1 3. Logics: Predicates and values. PA1 1. A stored knowledge base called code truth table. It is a two-dimensional array of numbers or characters. This is a new type of knowledge base stored in the storage of computer. It is the working knowledge base. PA1 2. An input knowledge base. This knowledge base is not a set of `if-then` rules. It is a truth table called input truth table. Its structure is just like a table in any relational database. PA1 3. An automatic inference engine (AIE). This is a new type of inference engine. It reasons any stored knowledge base by a double loop without compilation. No matter what the size of the input knowledge base is, and no matter what kind of knowledge is stored, the double loop always proceeds the inference automatically. Therefore, the inference engine is called the automatic inference engine and the system is called the automatic expert system. PA1 (a) An input knowledge base (IKB) in the form of a truth table is called input truth table (ITT); PA1 (b) An Attribute-value table (AVT) is defined and inputted by the user, and the format of the ITT is defined by the AVT; PA1 (c) A stored knowledge base in the form of a two-dimensional array is called the code truth table (CTT). Each entry of the CTT is a code of the value of the corresponding entry of the ITT; PA1 (d) A transfer engine (TE), which is a build-in computer program, translates values in the ITT to their corresponding codes in CTT and translates the codes in CTT back to its corresponding values in ITT by the aid of the AVT; and PA1 (e) An automatic inference engine (AIE), which is a build-in computer program, reasons the CTT automatically.
Among these three types, the rule-based knowledge base is the most commonly used one. In some applications, knowledge bases are very big, and may contain thousands of `if-then` rules. They are built by the cooperation of domain experts and knowledge engineers, who are software engineers familiar with the structures and requirements of expert systems and the expert system shells. The `if-then` rules or frames of knowledge bases generally are totally different from any knowledge representation formats in domain experts' professional or daily life. Domain experts need the help of knowledge engineers in the process of design and creation of any knowledge bases. In order to be executed, the created knowledge base needs to be compiled and integrated with the inference engine.
The cooperation of domain experts and knowledge engineers is the most time-consuming, and maybe the most money-consuming process. And it is the most difficult part in building the expert system. As human knowledge is growing up rapidly, the knowledge base needs to be modified frequently. In modification phase, the cooperation of domain experts and knowledge engineers is still necessary. Therefore, since 70's, it is believed that the process, which involves domain experts and knowledge engineers working together to design, construct, and modify the domain knowledge base is the main bottleneck in the development of expert systems.
Until today, the bottleneck problem remains unsolved. Most expert systems and commercial expert system shells still use `if-then` rule-based knowledge bases. And domain experts and knowledge engineers still have to work together to design and create domain knowledge bases. Not only the commercial expert system shells in the market, but also the recently applied and approved patents, such as U.S. Pat. No. 4,970,657 (Expert Knowledge System Development Tools, U.S. Advanced Technology, 11/90), U.S. Pat. No. 4,970,658 (Knowledge Engineering Tools, Tesseract Corp, 11/90), and U.S. Pat. No. 4,912,648 (Expert System Inference Engine, IBM, 3/90), still use the `if-then` rule-based or frame-based knowledge base structures.
Most current marketing expert system shells are designed for the knowledge base in the form of `if-then` rules. They need not only an editor screen to input and modify the rules in the knowledge base but also a program to compile, integrate, and link the input knowledge base and the stored inference engine together. (The Rete algorithm developed and published by Forgy in 1982 is a widely used example, but it is pretty complicated.)
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to the structure of an air bag door of an instrument panel, and particularly, to the structure of an air bag door that is integral with an instrument panel.
2. Description of the Related Art
FIG. 16 shows an instrument panel P of a car. The instrument panel is arranged inside the car under a windshield, to hold instruments and protect persons in the front seat. The instrument panel is generally made of a base, a skin, and a polyurethane foam body formed between the base and the skin. A simple way to form the instrument panel is to arrange a skin and a base in molds, inject polyurethane foam ingredient between the skin and the base, and make the foam ingredient foam and solidify with the skin and base. This technique is called a monolithic molding technique.
Recent instrument panels are usually provided with an air bag device for the seat next to the driver's seat. FIG. 17 is a sectional view taken along a line a--a of FIG. 16 and shows an air bag device fitted to the instrument panel of FIG. 16. A folded air bag A and an igniter I are housed in a casing C, to form the air bag device. The air bag device is fitted to the back of the instrument panel P so that the air bag device faces the seat next to the driver's seat. The base 74 has an opening O above the casing C, to let the air bag A inflate. The opening O is covered with an air bag door D. Upon occurrence of a collision the car, the igniter I inflates the air bag A, which pushes and opens the door D from the back thereof and expands into the inside of the car.
The air bag door D may be separately prepared and fitted to the instrument panel later, or it may be integrally formed with the instrument panel.
Separately preparing the door D involves troublesome fitting work and fitting errors. On the other hand, integrally forming the door D has no such problems. The present invention relates to the latter method.
The instrument panel of the prior art of FIGS. 16 and 17 has the integral air bag door D. FIG. 18 is an enlarged view showing an encircled part of FIG. 17. The instrument panel P is formed according to the monolithic molding technique and is composed of the base 74, an air bag door core 75, the skin 72, and the foam body 71. The base 74 has the opening O for passing the air bag. The door core 75 is placed on the base 74, to close the opening O. The skin 72 has a breaking facility 73 that defines the air bag door D. The foam body 71 fills a space between the base 74 and the skin 72.
The breaking facility 73 is a notch or a V-shaped groove formed by thinning the skin 72 by high-frequency welder, hot blade, cold press cutter, etc. A reference mark T is an expected break line that is an imaginary line passing through the foam body 71.
If inflated, the air bag A pushes the air bag door D. Stress due to the inflating air bag appears at the breaking facility 73 and breaks the foam body 71 and breaking facility 73, to open the air bag door D and expand the air bag A into the inside of the car as shown in FIG. 19. In FIG. 19, the skin 72 has been broken at parts 73a and 73b, and the foam body 71 at parts Ta and Tb.
The expected break line T is a shortest ideal line achieved when the foam body 71 breaks most efficiently in a shortest time. The line T is only an imaginary line and is not a real line formed of, for example, a slit. The actual broken parts Ta and Tb are usually irregular and differ from the ideal line T. Namely, the air bag door D is irregularly opened and the foam body 71 is irregularly broken to scatter.
It is difficult to form a notch or a slit along the line T in the foam body 71 because the foam body 71 is made from polyurethane foam ingredient between the base 74 and the skin 72.
The polyurethane foam ingredient frequently leaks from between the opening O and the door core 75, to cause an underfill in the foam body 71. To prevent this, more polyurethane foam ingredient is needed. If the ingredient leaks, extra work of removing burrs formed by the leaked ingredient will be necessary.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Aside from being used in tires, rubber is used in a variety of other parts for automobiles, and other motorized vehicles and machines. In those environments, the components made from rubber have to withstand exposure to different chemical environments, such as oil, water, air or ozone, without losing the mechanical properties required for their intended use over a wide range of operating temperatures.
Hydrogenated nitrile rubbers, which have good heat-aging resistance and resistance to chemicals as well as suitable mechanical properties, are used in mechanical parts for performance in physical environments such as automobiles. However, the use of hydrogenated nitrile rubbers in some applications is limited by their relatively high cost.
Blends with other elastomers such as NBR, ECO, EPDM, CR, CPE, and the like have been considered. For example, U.S. Pat. No. 5,612,418 describes blends of a partially hydrogenated nitrile rubber and a polyacrylate elastomer. In general, some compromise of physical properties, especially heat resistance, must be made in such elastomeric blends. An important requirement for those blends is occuring between the elastomers to maintain key thermoset type properties, e.g., elevated temperature compression set resistance.
Also, in the prior art, attempts to combine the use of thermoplastic resins with rubbers have focused on using the rubbers as modifiers for the thermoplastic resins, in proportions such that the rubbers are dispersed as discrete particles, which may be partially vulcanized, in a matrix of the elastomers. For example, thermoplastic resins thus modified with hydrogenated nitrile rubbers are known. However, those compositions are not suitable for applications for which rubbers are usually used. In other words, such rubber-modified elastomers do not have sufficient rubber-like properties.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Such front derailleur devices are known from the prior art. For example, documents DE 10 2014 010 367 A1 and DE 10 2014 007 566 A1 describe front derailleur devices of this type. These are configured such that the derailleur device is pretensioned via a spring mechanism in a particular operating position, for example in the operating position of the bicycle chain in which the chain lies on the smallest chain wheel. The chain cage is in a position in which it holds the bicycle chain on the smallest chain wheel. In order to actuate the derailleur device so that the chain cage is pivoted via the hinge arrangement such that the bicycle chain is moved to the next larger chain wheel and as far as the largest chain wheel (insofar as the bicycle chain shift has more than two chain wheels), in such conventional front derailleur devices an actuating force is exerted on the derailleur device via a Bowden cable. This actuating force is sufficiently large to overcome the pretension force and thus causes a displacement of the chain cage into the desired operating position.
One essential aspect of such front derailleur devices lies in the geometric arrangement of the hinge arrangement which is pivotable relative to the frame fixing part. Normally, hinge arrangements are used with two parallel pivotable lever arms, wherein each lever arm is mounted with one end pivotably on the frame fixing part and with its other end pivotably on the chain cage. Overall, this gives a type of parallelogram mechanism so that the chain cage can be moved on an orbit in a predefined alignment. The two documents mentioned above show arrangements in which the chain cage is pivoted sideways in the manner described above in a substantially horizontal plane or in a plane tilted slightly to the horizontal. In this context, we also speak of “side swing” derailleurs.
Such “side swing” derailleur devices have been known for a long time in the prior art, for example from documents EP 0 042 274 A2 or EP 0 104 110 B1.
An essential advantage of such “side swing” derailleur devices is that they can be arranged with their mechanical components substantially to the side of the frame tube. In modern bicycles with frame geometries with short chain struts and large running wheel diameters, relatively little space is available behind the seat tube of the frame. This applies both to the mechanical components of the derailleur device itself and to components for guiding the control cable with which the derailleur device is actuated.
As an alternative to “side swing” derailleur devices, derailleurs are known in which the chain cage pivots in the vertical direction, so-called “top swing” arrangements. Such a front derailleur device is shown and described for example in document U.S. Pat. No. 4,613,319. In this arrangement, the chain cage is pivoted from a bottom position above the smallest chain wheel upward to the largest chain wheel. A similar arrangement is shown and described in document U.S. Pat. No. 4,030,374. This arrangement is also configured as a “top swing” arrangement. This document has the feature that a leaf spring is screwed to one of the hinged struts of the hinge arrangement, protrudes over the hinged strut and rests in a sprung manner on an arm. This solution is also space-consuming and has not therefore proved successful in practice.
An important aspect of modern derailleur devices lies in the inward and outward routing of the control cable. Because of the ever more complex frame geometries, conventional guide routes of the control cable, for example along the seat tube, are often no longer advantageous. It is an object of the present invention to propose a front derailleur device of the type described initially which, with simple and economic construction and reliable function, takes up little construction space and allows an advantageous guidance of the control cable.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Minerals such as talc, mica and sericite, metal oxides such as titanium dioxide, zinc oxide and iron oxides, thermoplastic powders, organic pigments such as starch and cellulose, and other inorganic pigments are widely used in cosmetic products. Although they can be used without treatment, their performance can be significantly improved through surface treatment. Special properties such as water-proofness, low oil absorption, higher solids loading, softness, enhanced dispersibility, and resistance to low pH can be enhanced through surface treatment.
Most common surface modifying agents, such as methicone, silane, dimethicone, titanate, magnesium myristate and perfluoroalcohol phosphate are all synthetic compounds and may involve undesirable complications.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
An upper basket is known in particular from the state of the art, for example, a dishwashing machine G 641 PLUS that is manufactured and distributed by the present applicant, said upper basket comprising a cup support on its side wall, where the cup support is pivotably mounted on the basket. Pivoting reveals a second shelf in the area of the basket for depositing cups, so that coffee cups, bowls or the like can be stacked one above the other in the basket. For example, if this cup support is also to be used for tall glasses or bowls, there is the possibility of folding up the cup support so that the entire area can be used as storage space.
With this known cup support, it is regarded as a disadvantage that the possibility of variation is limited with this pivotable cup support because only two possible shelf adjustments are possible.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to an outside through fishing line guide.
2. Description of the Conventional Art
In recent years, while a Super braided line (an ultra high molecular weight polyethylene multi filament line) is sold as a fishing line, this Super braided line has an extremely higher strength than a conventional nylon line or fluorocarbon line, and becomes a mainstream of the fishing line. However, since it is a so-called Super braided line as is different from a conventional monofilament line, it has no tension and is extremely flexible. Accordingly, a tangle tends to be generated in comparison with the conventional fishing line, and any tangle prevention measure has been demanded.
Accordingly, the tangle is generated in various fields of the fishing. In addition to a typical case that the fishing line passing through a line guide ring of a fishing line guide goes around a rear side of the line guide ring due to “line slack” or the like, and is tightened around the fishing line guide so as to generate a tangle, there is a case that the fishing line before passing through the line guide ring is tightened around the fishing line guide so as to generate the tangle, just after casting.
With regard to the latter, a description will be given in detail by exemplifying a fishing rod to which an upright type fishing line guide 101 shown in FIG. 13 is installed. In a moment of casting, as shown in FIG. 13(1), a straight fishing line which is not wound around a spool of a reel passes through a line guide ring 103 without any problem, and a spiral fishing line released from the spool so as to be drawn out is subsequently choked by the line guide ring 103 so as to pass approximately straightly, as shown in FIG. 13(2). However, if the choking is not smoothly carried out, a speed of the passing fishing line slows down, and the spiral fishing line starts staying at a rear side of the line guide ring 103. Further, if it stays beyond a certain degree of amount, the spiral fishing line next overflows from one side of the line guide ring 103 so as to come out forward. Under such the state, if the overflowing spiral fishing line is guided to the other side by being exposed to a suitable wind (a wind from a left side in this case) as shown in FIG. 13(4), it gets into a portion between the fishing line after passing and the fishing line guide 101, and there is further the case that it covers the line guide ring 103, as shown in FIG. 13(5). Since the speed of the trailing fishing line slows down immediately, the fishing line covering as mentioned above is pulled back to a butt side and goes forward to a tip side while passing through the line guide ring 103. However, if a covering degree is small, it is disentwined while slipping along an outer periphery of the line guide ring 103 at a time of being pulled back. However, as shown in FIG. 13(6), if the covering degree is large, it is tightened around the line guide ring 103 so as to generate the tangle.
In order to dissolve the tangle, there has been proposed a structure in which a pair of side support legs of the fishing line guide are inclined to the tip side. There is considered that if a rod body is properly swung in such a manner as to cast a device, the fishing line enwinding around the fishing line guide smoothly slides up on the inclined surface and finally comes off upward from the tip side, so that the tangle is dissolved.
Reference is made to Japanese Unexamined Patent Publication No. 2000-253778.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
In the related art, as a panel structure of a sun roof, for example, a structure described in JP 2015-140084 (Reference 1) is known. The panel structure of a sun roof includes a panel (sun roof panel), an inner panel (holder) that is attached to a peripheral portion of a lower surface of the panel and has a recessed portion, a lid member that closes an opening of the recessed portion, and a resin covering member (holding member) that is molded so as to integrate the panel, the inner panel, and the lid member. The inner panel has a flange portion and the end portion of the lid member is clamped between an upper surface of the flange portion and a lower surface of the panel. The covering member has a clamped portion that intrudes into a space surrounded by the upper surface of the flange portion, the lower surface of the panel, and an end surface of the lid member, and the lid member is disposed over a pair of opening edge portions of the recessed portion and closes the recessed portion. The clamped portions are formed on both sides of the lid member with the recessed portion is interposed therebetween.
According to the configuration, since the opening of the recessed portion of the inner panel is closed by the lid member, resin that is a material of the covering member does not intrude into the recessed portion during molding the covering member. Therefore, it is possible to reduce the amount of resin used during molding the covering member and to reduce a mass of the panel structure as a whole by not disposing a spacer such as a foamed resin within the recessed portion.
However, in Reference 1, since the lid member closes an entirety of the opening of the recessed portion, it is necessary to set dimensions thereof depending on an opening width of the recessed portion. In other words, since different types of the lid members are required for the inner panels having different shapes of the recessed portions, versatility is impaired.
Thus, a need exists for a panel structure of a sun roof which is not susceptible to the drawback mentioned above.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to a method of preparing a toner and to the toner prepared using the method. More particularly, the invention relates to a method of preparing a toner by regulating the amounts of a reactive emulsifier and a macromonomer to control the configuration of toner particles, and the resulting toner. An image forming method using the toner, and an image forming apparatus employing the toner are also provided by the invention.
2. Description of the Related Art
In an electrophotographic process or an electrostatic recording process, a developer used to form an electrostatic image or an electrostatic latent image may be a two-component developer, formed of a toner and carrier particles, or a one-component developer, formed of a toner only. The one-component developer may be a magnetic one-component developer having magnetic properties or a nonmagnetic one-component developer having no magnetic properties. Plasticizers such as colloidal silica are often added independently into the nonmagnetic one-component developer to increase the flowability of the toner. Generally, coloring particles obtained by dispersing a colorant, such as carbon black, or other additives in a binding resin are used in the toner.
Methods of preparing toners include pulverization or polymerization. In pulverization, the toner is obtained by melt mixing synthetic resins with colorants and, if needed, other additives, pulverizing the mixture and sorting the particles until particles of a desired size of are obtained. In polymerization, a polymerizable monomer composition is manufactured by uniformly dissolving or dispersing a polymerizable monomer, a colorant, a polymerization initiator and, if needed, various additives such as a cross-linking agent and an antistatic agent. Next, the polymerizable monomer composition is dispersed in an aqueous dispersive medium which includes a dispersion stabilizer using an agitator to form minute liquid droplet particles. Subsequently, the temperature is increased and suspension polymerization is performed to obtain a polymerized toner having coloring polymer particles of a desired size.
In an image forming apparatus such as an electrophotographic apparatus or an electrostatic recording apparatus, an electrostatic latent image is formed through light-exposing the surface of a photoreceptor which is uniformly charged. A toner is attached to the electrostatic latent image, and a resulting toner image is transferred to a transfer medium such as a paper through several processes such as heating, pressing, solvent steaming, etc. In most fixing processes, the transfer medium with the toner image passes through fixing rollers and pressing rollers, and by heating and pressing, the toner image is fused to the transfer medium.
Images formed by an image forming apparatus such as an electrophotocopier should satisfy requirements of high precision and accuracy. Conventionally, a toner used in an image forming apparatus is usually obtained using pulverization of the toner material. When using pulverization, color particles having sizes in a large range are likely formed. Hence, to obtain satisfactory developer properties, there is a need to sort the coloring particles obtained through pulverization according to size to reduce the particle size distribution. However, it is difficult to precisely control the particle size distribution using a conventional mixing/pulverizing process in the manufacture of toner particles suitable for an electrophotographic process or electrostatic recording process. Also, when preparing a minute particle toner, a toner preparation yield is low due to a sorting process. In addition, there is a limit to a change/adjustment of a toner design for obtaining desirable charging and fixing properties. Accordingly, polymerized toners, in which the size of particles is easy to control and which do not need to go through a complex manufacturing process such as sorting, have come into the spotlight recently.
When a toner is prepared using polymerization, a desired particle size distribution is obtained without performing pulverization or classification.
U.S. Pat. No. 6,033,822 to Hasegawa et al. discloses a polymerized toner including a core formed of colored polymer particles and a shell covering the core in molecules, wherein the polymerized toner is prepared by suspension polymerization. However, it is still difficult to adjust the shape of the toner and the size of the particles using the process. Also, this process results in a wide particle size distribution.
U.S. Pat. No. 6,258,911 to Michael et al. discloses a bi-functional polymer having a narrow polydispersity and an emulsion-condensation polymerization process for manufacturing a polymer having covalently bonded free radicals on each of its ends. However, even when this method is used, a surfactant can cause an adverse effect, and it is difficult to control the size of the latex particles.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention relates in general to wireless control of animals and, more particularly, to such systems using one or more wireless transmitters with a receiver attached to the animal for administering control stimuli to the animal.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
In percutaneous transluminal coronary angioplasty (PTCA) procedures, a guiding catheter is advanced until the distal tip of the guiding catheter is seated in the ostium of a desired coronary artery. A guidewire, positioned within an inner lumen of a dilatation catheter, is first advanced out of the distal end of the guiding catheter into the patient's coronary artery until the distal end of the guidewire crosses a lesion to be dilated. Then the dilatation catheter having an inflatable balloon on the distal portion thereof is advanced into the patient's coronary anatomy, over the previously introduced guidewire, until the balloon of the dilatation catheter is properly positioned across the lesion. Once properly positioned, the dilatation balloon is inflated with fluid one or more times to a predetermined size at relatively high pressures (e.g. greater than 8 atmospheres) so that the stenosis is compressed against the arterial wall and the wall expanded to open up the passageway. Generally, the inflated diameter of the balloon is approximately the same diameter as the native diameter of the body lumen being dilated so as to complete the dilatation but not overexpand the artery wall. Substantial, uncontrolled expansion of the balloon against the vessel wall can cause trauma to the vessel wall. After the balloon is finally deflated, blood flow resumes through the dilated artery and the dilatation catheter can be removed therefrom.
In such angioplasty procedures, there may be restenosis of the artery, i.e. reformation of the arterial blockage, which necessitates either another angioplasty procedure, or some other method of repairing or strengthening the dilated area. To reduce the restenosis rate and to strengthen the dilated area, physicians frequently implant a stent inside the artery at the site of the lesion. Stents may also be used to repair vessels having an intimal flap or dissection or to generally strengthen a weakened section of a vessel. Stents are usually delivered to a desired location within a coronary artery in a contracted condition on a balloon of a catheter which is similar in many respects to a balloon angioplasty catheter, and expanded to a larger diameter by expansion of the balloon. The balloon is deflated to remove the catheter and the stent left in place within the artery at the site of the dilated lesion. Stent covers on an inner or an outer surface of the stent have been used in, for example, the treatment of pseudo-aneurysms and perforated arteries, and to prevent prolapse of plaque. Similarly, vascular grafts comprising cylindrical tubes made from tissue or synthetic materials such as polyester, expanded polytetrafluoroethylene, and DACRON may be implanted in vessels to strengthen or repair the vessel, or used in an anastomosis procedure to connect vessels segments together.
In the design of catheter shafts, strength, stiffness and flexibility of various sections of the catheter shaft are specifically tailored to provide the desired catheter performance. However, one difficulty has been optimizing the often competing characteristics of strength and flexibility of the catheter shaft.
Accordingly, it would be a significant advance to provide a catheter having a catheter shaft with an improved combination of characteristics such as strength, flexibility and ease of manufacture. This invention satisfies these and other needs.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
This invention relates to magnetic disk drives, and more particularly, to a head arm assembly having both servo and read/write heads thereon.
Magnetic disk units are extensively used in computer systems. Large magnetic disk units generally have a magnetic read/write assembly which is moved radially from track to track across a stack of magnetic disks. Examples of such drives are the IBM 3350 supplied by International Business Machines Corporation and STC 8350, supplied by Storage Technology Corporation. Recently, many small disk drives have been developed for minicomputer systems. An example of this type of drive is the IBM System 32 and comparable magnetic disk drives made by other companies. These disk drives usually make use of a magnetic head disk technology which is referred to as "IBM/Winchester".
High density magnetic disk drives have positional information recorded on one of the disks. A servo head reads this positional information to generate a servo signal which indicates the position of the read/write heads with respect to the magnetic disks in the stack.
In the prior art, the actuator for the magnetic head assemblies drives a plurality of read/write head arm assemblies having data read/write heads thereon, and one servo arm assembly having a single head thereon to generate the servo signal. The servo tracks are generally recorded on one of the extreme surfaces of the disk pack, for example on the bottom surface of the bottom disk in the pack. One reason for this arrangement is that it minimizes the interference between the data signals and the servo signals. However, the use of a dedicated arm assembly with a single servo head in this manner introduces other problems. If the axis of the stack of magnetic disks is tilted, an error is introduced between the track position indicated by the servo signal and the actual track position on disks other than the servo disk. When the servo track is on one of the extreme surfaces of the stack, this error is maximized on the disk surface at the other extreme of the stack. It would be more desirable to have the servo track intermediate the extremes of the stack. In this way, the off track error caused by tilt would be shared by the read/write heads on both sides of the stack from the servo disk. Also, the thermal environment experienced by the servo head would be more representative of the data heads and thus reduce arm related thermal distortion response. However, this is not feasible with a dedicated servo arm assembly with a single servo head as in the prior art. The use of such a dedicated servo arm in the middle of the stack would waste disk surface. The surface opposite and adjacent to the servo surface would not have read/write heads engaging it. Alternatively, an extra read/write head arm assembly would have to be provided for this otherwise unused surface.
It is an object of the present invention to provide a head arm assembly which minimizes interference between data and servo signals, which is positioned between the extremes of the disk stack, and which has both servo and read/write heads thereon, so that reading and writing can be accomplished efficiently from all disk surfaces.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Related Field
The present invention relates to a knee orthosis for support of a knee joint in the case of instability, comprising a thigh portion, attachable on the thigh via fixing means, with an upper half shell and hinge plates fixed to the half shell, a lower leg portion, attachable to the lower leg via fixing means, with a lower half shell and splint elements attached laterally on the lower half shell, which splint elements are connected to the respective hinge plate via articulation means and in which splint elements, in the regions remote from the articulation means, the lower half shell is pivotably borne about a pivot axis and is pivotable toward the lower leg via adjustment means.
Related Art
Especially with knee instability owing to injury of the cruciate ligaments it is necessary for the knee joint to be supported in order to prevent in particular a defective position of the tibia to the femur. Knee orthoses are used for this purpose which give the knee joint the desired stability. It has been shown that with knee orthoses of this kind, especially with bent knee as occurs, for example, in a sitting position of the respective person, a displacement of the tibia to the femur nevertheless results. A displacement of this kind can have as a consequence an overstretching of the corresponding cruciate ligaments, which can occur both with a surgical as well as with a conservative treatment of the injury and should be avoided as much as possible.
The patent publication DE 102 59 751 A1 discloses a knee orthosis which is supposed to prevent such a displacement of the tibia to the femur. For this purpose this knee orthosis is designed in such a way that the lower half shell of the knee orthosis is pressed, via an adjustable spring pressure, toward the upper region of the lower leg in order to thereby counteract a movement of the tibia to the femur.
It has thereby been shown that this pressure against the upper region of the lower leg is not optimal. Thus, for example, this pressure can have the desired magnitude in the bent position of the knee, but in the stretched position of the knee this pressure is too great, which is disadvantageous.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to a slide rail assembly, and more particularly, to a slide rail assembly with a damping device capable of providing damping effect while two rails of the slide rail assembly are relatively moved.
2. Description of the Prior Art
Generally, a slide rail assembly comprises a first rail and a second rail movable relative to the first rail. Preferably, the slide rail assembly further comprises a third rail movably mounted between the first rail and the second rail for forming a so-called three-section slide rail assembly.
In the prior art, when the second rail and/or the third rail is opened relative to the first rail along a first direction or retracted relative to the first rail along a second direction, a user cannot aware that the second rail and/or the third rail is going to arrive at a specific position relative to the first rail. Therefore, the slide rail assembly of the prior art cannot meet specific market requirements
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention relates to a new and improved construction of smoke detector containing a radiation source operated in a pulse-like or intermittent mode.
In its more particular aspects the smoke detector of the present development is of the type comprising a pulse-operated radiation source emitting focussed radiation into a region freely accessible to environmental air, a radiation receiver arranged in the region of said radiation or radiation pulses, and an input amplifier series connected to the radiation receiver and generating output pulses proportional to the intensity of the radiation impinging upon the radiation receiver. There are also provided an evaluation circuit comprising a reference voltage generator for generating a reference voltage for comparison with the output pulses, and an alarm stage defining an alarm threshold for triggering an alarm signal when the output pulses have been attenuated below a predetermined value of the alarm threshold for more than a first predetermined period of time. There is further provided a disturbance circuit or stage defining a disturbance threshold and triggering a disturbance signal when the output pulses have been more rapidly attenuated than during triggering the alarm signal, and wherein the disturbance threshold is lower than the alarm threshold.
A smoke detector of the aforementioned type is known, for example, from German Patent Publication No. 2,822,547. In the smoke detector described therein the radiation source and the radiation receiver are accommodated in two different housings, as is usual in such so-called "line extinction alarms or detectors". These housings are mounted at the walls of the room or area to be monitored at a distance from one another depending on the requisite location of use. A fixed alarm threshold is predetermined which, however, depending upon the different distances between the radiation source and the radiation receiver corresponds to totally different smoke densities.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
This invention relates to a method for controlling the shape of material in rolling processes, and more particularly to a method for controlling the shape of a cold-rolled material.
2. Discussion of Background
For the control of the shape of rolled material which is obtained by a cold rolling operation, it has been the conventional practice to employ the thermal crown control in addition to the work roll bending control which control the roll camber by varying the bending load of the work roll.
Shown in FIG. 1 is a typical thermal crown control method, in which a plurality of coolant spout nozzles 2 are provided at intervals in the axial direction of a barrel shaft of a work roll 1 for spurting a roll coolant therefrom, and the shape of the rolled material is detected by a shape detector (not shown) which produces shape parameters P as its output signal. The shape parameters P are led to a coolant supply control unit 20 thereby to calculate a local deviation .epsilon.(j) of the shape parameter P at a position j in the axial direction of the barrel shaft from a target shape parameter M, supplying a valve opening control signal proportional to the local deviation .epsilon.(j) to a flow control valve 3 for a coolant spout nozzle 2 which is located at the position j in the axial direction of the barrel shaft. Indicated at 4 is a roll coolant circulating tank, at 5 a feed pump, and at 6 is a main piping.
The above-described conventional method, however, has a problem in that the cooling capacity of the roll coolant becomes insufficient even at a maximum flow rate in some cases because the temperature of the roll coolant is at a constant level. Of course, it is possible to provide a roll coolant of a lower temperature (a cold coolant) in addition to the ordinary roll coolant (a hot coolant), and to switch to the cold coolant when the cooling capacity beomes deficient. The cooling capacity can be increased by this method, but there arises another problem that the sudden change of the cooling capacity makes the control of the thermal crown discontinuous. Further, in a case where the rolled strip contains a sheet crown, the accuracy of the shape control is impaired by variations in the contact angle of the rolled strip with the shape detector or sensor roller in the width wise direction of the strip, which cause differences in detected axial load between the center and end portions of the strip.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention relates to a new form of Pennisetum alopecuroides plant named ‘Yellow Ribbons’. ‘Yellow Ribbons’ is a seedling of an unnamed Pennisetum alopecuroides, not patented, characterized by yellow foliage and yellow-green inflorescences on 50 cm stems that start in mid-August in northern Illinois. The new plant is the result of a breeding program taking place at a wholesale perennial nursery since 2001. The seedling was grown by the inventor at a wholesale perennial nursery in Hebron, Ill. in 2016. The selection of the new plant was due to its yellow foliage and yellow-green inflorescences on 50 cm stems that start in mid-August in northern Illinois. Asexual, vegetative division propagation has been the only means of reproduction. Propagation has taken place at a wholesale perennial nursery Hebron, Ill. in 2017. To date these plants have remained uniform in height. The new Pennisetum has shown to be stable and identical in reproduction to the parent after making over 500 vegetative divisions in 2018. No plants of the new Pennisetum have been sold in this country, or anywhere in the world, prior to the filing of this application, nor has any disclosure of the new plant been made prior to the filing of this application with the exception of that which was disclosed within one year of filing of this application and was either derived directly or indirectly for the inventor.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
In recent years surgery has markedly advanced through the performance of laparoscopic and endoscopic surgical procedures such as cholecystectomies, gastrostomies, appendectomies, and hernia repair. These procedures are accomplished through a trocar assembly, which is a surgical instrument used to puncture a body cavity. The trocar typically contains a sharpened obturator tip and a trocar tube or cannula. The trocar cannula is inserted into the skin to access the body cavity, by using the obturator tip to penetrate the skin. After penetration, the obturator is removed and the trocar cannula remains in the body. It is through this cannula that surgical instruments are placed.
One surgical instrument that is commonly used with a trocar cannula is a surgical clip applier for ligating a blood vessel, a duct, shunt, or a portion of body tissue during surgery. Most clip appliers typically have a handle with an elongate shaft having a pair of movable opposed jaws formed on an end thereof for holding and forming a ligation clip therebetween. The jaws are positioned around the vessel or duct, and the clip is crushed or formed on the vessel by the closing of the jaws.
In many of the prior art clip appliers, the feeding and forming mechanisms require precise timing and coordinated movement of components to operate. This need for precise timing and control has resulted in the need for complex mechanical designs, thereby increasing the cost of the clip appliers. Many prior art clip appliers also use a spring-loaded clip advancing assembly to advance one or more clips through the shaft of the device. As a result, the jaws must contain a mechanism for preventing accidental projection of the clip from the device before the clip is formed. Other drawbacks of current clip appliers include the inability to handle an overload applied to the jaws by the trigger under a variety of conditions. Many devices require full closure of the jaws, which can result in overload on the jaws when the vessel or duct positioned therebetween is too large to allow full closure, or when a foreign object is positioned between the jaws.
Accordingly, there remains a need for improved methods and devices for applying surgical clips to vessels, ducts, shunts, etc.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention generally relates to pulse-width-modulated (PWM) inverters and, more particularly, to an improved real-time method and apparatus for generating modulating patterns which compensate for d.c. link harmonics.
2. Description of the Prior Art
PWM inverters are employed to convert direct current (d.c.) to alternating current (a.c.). In many applications, it is important to carefully regulate the quality of the a.c. generated by the inverter. Accordingly, it is customary to define a point of regulation (POR) downstream of the inverter at which the voltage and current of the a.c. signal generated by the inverter is sampled. The sampled voltage and current would be used to select appropriate PWM switching patterns to minimize distortion at the POR. Based on the voltage and current sensed at the POR, an inverter controller selects or creates in real time an appropriate PWM pattern to ensure the least distortion at the POR. As real and reactive power factors of electrical loads coupled to the inverter change, the PWM patterns fed to the inverter are changed.
A PWM pattern comprises a set of switching transients which, when applied to a d.c. signal via an inverter, produces alternating pulses which, when filtered, approximates a sinusoidal a.c. signal. The pulses in a PWM pattern are of varying width.
Prior inventions have addressed schemes for controlling the harmonic content of the inverter output caused by changes in load parameters. Representative of such inventions is U.S. Pat. No. 4,527,226 to Glennon, which discloses an inverter control system for a PWM inverter circuit. This circuit comprises an angle set look up table and selection logic for addressing the look up table. The angle set defining the inverter output waveform is selected in response to various operating conditions of the inverter. However, considering the number of parameter values and the degree of regulation desired, the number of patterns which must be stored can be prohibitively large.
Additional prior art approaches to pattern generation include the following patents. An earlier patent to Glennon, U.S. Pat. No. 4,382,275, is directed to a PWM inverter having an output signal with reduced harmonic content, wherein a filtered fundamental PWM signal is summed with a controlled signal.
U.S. Pat. No. 4,595,976 to Parro, II discloses an inverter control which is an enhancement of the Glennon inverter control. More specifically, the table look up is implemented as a plurality of memories, one for each phase, each of which is subdivided into a plurality of memory blocks which store a number of bytes. Memory address decoding logic addresses a particular memory block in each memory in accordance with a control signal representing the desired waveform to be generated at each phase output. Thus, the Parro, II inverter control accomplishes individual phase regulation of the inverter output.
U.S. Pat. No. 4,635,177 to Shekhawat et al., discloses a further refinement of the basic Glennon inverter control system. More specifically, the Shekhawat et al., control permits on-line generation of PWM patterns for a neutral point clamped PWM inverter. A microprocessor and memory are coupled to the generating circuitry for calculating switching points for the inverter switches during operation of the inverter. Timer modules are coupled to the microprocessor for developing switch points so that the switches are operated to reduce the distortion of the inverter output signal.
U.S. Pat. No. 4,480,299 to Muto et al., also discloses a microprocessor controller inverter control. However, the Muto et al., PWM inverter is controlled by the use of the fundamental wave voltage of the inverter output as a feedback quantity. Muto et al. fail to show any apparatus for directly dealing with the physical limitations within the inverter itself.
Other patents related to the art of inverters include U.S. Pat. Nos. 3,648,150 to Kerick et al., and 4,626,979 to JaQuay. The Kerick et al., patent discloses an apparatus for comparing a filtered output of a PWM inverter with a reference waveform and generating output voltage signal to control the inverter drive circuit to produce an output waveform substantially duplicating the reference waveform. The JaQuay patent is similar to the Kerick et al. patent in that it is directed to a PWM inverter, including a comparitor for comparing an output voltage with the sum of a reference voltage and a maximum allowable ripple voltage.
Also representative of the prior art are U.S. Pat. Nos. 4,646,221 to Sekino et al., 4,757,434 to Kawabata et al., 4,800,478 to Takahashi, and 4,757,432 to Hancock. The patent to Sekino et al., is directed to a controlling circuit which monitors the output waveform of the inverter and controls the firing of the switch elements in the inverter to restore it to a sinusoidal waveform in the event that it is distorted by nonlinear loads. The patent to Kawabata et al., is directed to a control circuit for a current control minor loop which monitors the instantaneous value of the output current of the power conversion apparatus and adjusts it to the current reference value. The patent to Takahashi is directed to a control for an inverter, wherein an evaluation function on the whole combination of the inverter and the load connected to the a.c. side of the inverter is minimized. The patent to Hancock is directed to a device for time integrating the difference between the electrical output and the reference by varying the switching frequency in the inverters so as to null the difference in a feedback control loop.
The aforementioned co-pending application Ser. No. 07/507,489 discloses a system in which switching angles are calculated from an equation which describes the position of the switching angle for minimum output harmonic distortion as a function of a POR parameter or parameters.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Aircrafts have power requirements which are not related to propulsion. These can include ground services, such as providing air to the cabin, providing electrical power for the aircraft's system, and assisting with main engine start. These ground services are generally provided by one or more of the main propulsion gas turbine engines of the aircraft, or an auxiliary power unit (APU) on larger aircraft.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
There is an increasing need to reduce the power consumption of personal computers and other types of computing devices. A high-power consumption is undesirable because it increases the cooling requirements of the personal computer. Additionally, a high-power consumption is undesirable because it reduces the battery lifetime of mobile computers.
There are several components of a personal computer that draw significant amounts of power. First, the chip containing the central processing unit (CPU) draws power. Second, other chips, such as a graphics processing unit (GPU) or a bridge chipset, also consume power.
Additionally, a high-performance personal computer requires high-bandwidth data buses to transfer data between components. High-bandwidth data buses also consume a significant amount of power. The power required to operate a high-bandwidth data bus can be significant, particularly in the context of a mobile personal computer having a limited power budget.
Therefore, what is desired is an apparatus, system, and method for reducing bus power for a high bandwidth data bus.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Computing devices may include multiple applications that provide audio transmission for human listening. Web sites provide audio/visual services, including music streaming, video streaming, and the like. A computing device may include integrated hardware or software for controlling a master volume for all audio sound originating from software applications running on the device. In other aspects, software may be configured to detect and control external audio devices. Since each software application or external device is independent of each other, a user wishing to select, or control volume for, a single application or device from multiple applications and/or devices must operate the respective controls individually.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
As can be seen by reference to the following U.S. Pat. No's. 941,728 and 672,646 the prior art is replete with myriad and diverse laminated pool stick constructions.
While both of the aforementioned prior art pool stick constructions are more than adequate for fulfilling the basic purpose and function for which they have been specifically designed, neither of these patented devices are particularly useful for assisting a player in lining up a shot.
As most pool and billiard players are all too well aware, one of the most critical aspects of these sports is the proper alignment with the cue shaft and the surface of the cue ball to propel the cue ball in the proper trajectory towards the target ball or the sides of the table in accomplishing a desired shot.
Given the widespread popularity of pool and billiards it comes as somewhat of a surprise that to date no one has apparently developed a cue stick shaft construction that will incorporate an aiming reference line into the shaft material per se; such that the player may utilize the integrally formed reference line to align their shots and improve their game.
Obviously there has existed a longstanding need for such a construction and the provision of exactly this type of an arrangement is a stated objective of the invention.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Work machines, particularly tractors for agriculture, construction, earthmoving, forestry, and other towing applications, have improved over the years, both as to comfort for the operator of the work machine, and as to stress and loads applied against the work machine itself and against trailers or implements towed thereby, particularly as the machine moves over rough or irregular terrain, and for increasing the efficiency of operation by allowing for increased operating speeds and less operator fatigue. In particular, it is known for a work machine or tractor to have an automatic or selectably variable suspension or ride control, to improve operator comfort and allow for faster over-ground speed. It is also known for a tractor to have a drawbar for towing trailers and implements, which is resiliently supported, and/or automatically variable in height, length and/or sideward position, for functions such as accommodating different trailers or implements, loading conditions, and shock absorption. Reference in this regard, Bernhardt et al. U.S. Pat. No. 6,698,524 entitled Implement Hitch and Control System which is automatically operable for controlling the length of coupling elements of the hitch as a function of sensed forces applied against the coupling elements and position of an implement towed by the hitch, for controlling parameters including the operating line of draft forces acting on the hitch, towing point position, and/or inclination of a towed implement.
However, it has been found that even with a controlled suspension and/or ride control, and an automatically controllable hitch or drawbar, the automatic hitch or drawbar control may not suit individual operator preferences, and/or may not provide sufficient adaptability, either manual or automatic, for accommodating changing load and/or other operating conditions, such as braking and/or gear shifts/clutch operation. For instance, a towed trailer or implement, particularly a heavy one, or one which exerts a heavy load on the towing tractor, or a varying load thereon, can exert different forces and loads in different ways on a drawbar and thus on the towing vehicle, such as a tractor, as a result of a variety of factors. As an example, a drawbar control mode may be well suited for travel over paved roads, such as for travel between fields, involving only infrequent or occasional stopping, slowing and turning, but may be less suited to travel over irregular terrain such as a cultivated field wherein the drawbar is subjected to frequent jerking or jarring. Conversely, a control mode suitable for travel over rough or irregular terrain may be less suited for travel over smooth roads. The wrong control mode for a hitch or drawbar can negatively affect ride quality, steering, stability, and handling of a tractor, and thus operator satisfaction.
Even when environmental conditions such as terrain are consistent, load conditions can vary widely over a relatively short time period, such as when a grain cart being towed by a tractor is being filled with grain by a combine, or a fertilizer spreader towed by a tractor is spreading fertilizer over a field. In this regard, a grain cart can be loaded within a few minutes with an amount of grain having a weight which is several times the weight of a tractor towing the cart, thereby greatly changing the load on the drawbar. A fertilizer spreader can carry a load of fertilizer having an initial weight which is also several times the weight of the tractor towing the spreader, but which is gradually reduced to a much lower weight over the course of the spreading operation, which will also change the drawbar load. Further, towed implements such as agricultural drills and planters will exert a varying load on the drawbar of the towing vehicle as disks, plows or other tools of the implement are lowered into and raised from the ground, or, while in the ground encounter changing soil conditions or buried obstructions such as roots and old fence posts.
Still further, operation of the towing vehicle itself, either alone, or in combination with any of the above factors, can result in changes in drawbar loading conditions. For instance, drawbar loads will change when the towing vehicle is braked, and/or the clutch is engaged and disengaged, such as when shifting gears.
As a result, it has been found that it would be desirable to have a control for a drawbar of a hitch of a work machine, such as a tractor, which provides different selectable operating modes suitable for a variety of different operating and/or load conditions, as well as operator preferences, which is optionally automatically adaptable for changing conditions, such as when the towing vehicle is braking and/or the clutch is engaged or disengaged, and which overcomes one or more of the problems and shortcomings set forth above.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Weighing scales including a platform upon which an individual may stand and a base for housing structure both to support and translate movement of the platform relative to the base to movement of a graduated scale to be read are known. It is also known that the weighing scales may include an optical system whereby light from a source is passed through the graduated scale so that the image of indicium from the graduated scale is reflected by one or more mirrors to a projection screen carried by the platform. The image on the screen is representative of the weight of the individual. A form of the prior art weighing scales of this type may be seen in Grusin et al. U.S. Reissue Pat. No. 28,040, dated June 11, 1974.
While this form of prior art weighing scales overcomes what has been considered to be one of the principal objections to the weighing scales without the foregoing optical system, namely, the difficulty in read-out of weight, either because of the size or legibility of the indicia or inadequate lighting of the indicia, the prior art has the disadvantage that frequently inaccuracy is introduced to the read-out of weight because of deformation of the base structure upon which the source of light and the graduated scale are independently supported relative to the base. This problem becomes more prevalent through the mass production of weighing scales required to meet commercial demands and, although the deformation may be small, the magnification of the indicia of weight by the optical system can lead to non-negligeable errors in the read-out at the projection screen.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention relates generally to electronic systems and more particularly is directed to memory modules.
Memory modules are well known in the art and are commonly used in a wide variety of electronic systems, such as computer systems, to store data.
Memory modules typically comprise a circuit board, such as a printed circuit board, and one or more electronic components, such as integrated circuit (IC) memory chips, which are mounted directly on the circuit board. The circuit board is a substrate which electrically connects the electronic components mounted thereon in a desired configuration to form the functional memory module.
As noted above, memory modules are commonly used to store data for computer systems. Accordingly, memory modules typically include a plurality of connection points, such as a comb of printed terminals, formed along one edge which serve to electrically connect the memory module to the motherboard of the desired computer system. Specifically, memory modules are typically constructed in such a manner so that the plurality of connection points can be electrically and mechanically coupled to the motherboard of the desired computer system through a corresponding electrical connector.
It should be noted that the number and configuration of the connection points, or pins, on the memory module circuit board are commonly used to classify the memory module (e.g., a single in-line memory module (SIMM), dual in-line memory module (DIMM), etc.). Presently, computer industry standards mandate that computer systems be able to receive memory modules having a particular configuration and number of connection points (e.g., a 184-pin dual in-line memory module).
Designers of memory modules are constantly striving to increase, or expand, the memory capacity, or density, of memory modules. However, as noted briefly above, industry promulgated standards mandate that memory modules be designed to mechanically and electrically engage with a particular type of computer system electrical connector. Furthermore, because computer system designers typically limit the space within the housing of a computer system that is designated to receive a memory module, memory module designers are typically required to expand the module density of memory modules without significantly increasing its overall size. As a result, memory module designers are required to increase the memory capacity of memory modules while enabling each module to fit within the footprint of an industry-promulgated electrical connector and, at the same time, within the relatively confined space within the interior of the computer system which is designated for the memory module.
Design engineers utilize numerous well-known techniques to increase the memory density of a memory module without changing the size and/or connection point configuration of its circuit board.
As an example, memory module designers often use circuit boards which allow for electronic components to be mounted on both of its sides (this type of circuit board being referred to simply as a double-sided circuit board in the art). As can be appreciated, double-sided circuit boards enable design engineers to increase the number of electrical components which can be mounted on the circuit board, thereby increasing its overall density, without changing the size of the circuit board, which is highly desirable.
As another example, memory module designers often utilize individual electronic components of reduced size and of increased memory capacity, which is highly desirable.
As another example, memory module designers have, on occasion, coupled together multiple memory modules through the use of rigid flex technology. Specifically, a primary circuit board comprising the plurality of connection points is electrically coupled to a secondary circuit board through a flex circuit, each of the primary and secondary circuit boards having a plurality of electronic components mounted thereon. It should be noted that the flexibility of the flex circuit enables the primary and secondary circuit boards to be closely disposed in a substantially parallel configuration.
In U.S. Pat. No. 5,224,023 to G. W. Smith et al, there is disclosed an electronic assembly which combines a number of commensurate printed circuit boards that are bonded to a common, flexible, interconnecting substrate in an alternately folded and layered arrangement against an end board that has a comb of terminals for mounting into a motherboard connector. The flexible substrate is sandwiched between half-sections of each board, allowing mounting of components from both faces of the board. The assembly is particularly indicated for high density applications such as memory modules.
Although effective in increasing module density while maintaining the same height and electrical connector footprint as a memory module comprising a single printed circuit board, memory modules of the type described above which use rigid flex technology to connect multiple circuit boards together experience a few notable drawbacks.
As one drawback, memory modules which utilize rigid flex technology have been found to have a limited operating speed, which is highly undesirable. Specifically, it has been found that the speed in which signals can travel through the flex circuit is significantly limited. As such, a signal sent from an electronic component on the secondary circuit board reaches the comb of printed terminals on the primary circuit board significantly later (e.g., approximately 2 nanoseconds) than a signal sent from an electronic component on the primary circuit board. As a result, the memory module has a speed threshold which is limited to the speed in which signals can travel from the electronic components on the secondary circuit board to the comb of terminals on the primary circuit board. As can be appreciated, the calculated speed threshold for memory modules which utilize rigid flex technology has been found to be unacceptable in many present applications.
As another drawback, memory modules which utilize rigid flex technology have been found, at times, to perform inadequately, which is highly undesirable. Specifically, due to the significant length of the flexible substrate which connects the primary and secondary circuit boards, a signal generated from an electronic component on the secondary circuit board is required to travel along a relatively long trace length which, in turn, can result in integrity loss to the signal. As can be appreciated, it has been found that signals which travel along a trace length greater than 1.5 inches often experience significant integrity loss.
As another drawback, memory modules which utilize rigid flex technology have been found to be relatively expensive to manufacture, which is highly undesirable. Specifically, the cost associated with the flexible substrate is considerably high and, as a consequence, greatly increases the total overall cost of the memory module.
As another drawback, memory modules which utilize rigid flex technology have a considerably greater width (i.e., thickness) than other types of conventional memory modules, which is highly undesirable.
Accordingly, in order to increase the memory density of a memory module without changing the number, type and/or size of its circuit boards, memory module designers often assemble stacks of multiple (e.g., two, four, etc.) electronic components and, in turn, mount the stacks directly onto the circuit board. When utilizing this technique, design engineers commonly stack electronic components (i.e., integrated circuits) having a thin small outline package (TSOP) with a dual in-line lead configuration. It should be noted that when using this technique, each electronic component is individually manufactured, each component comprising a memory die which is at least partially encapsulated within a thin small outline package which includes a plurality of externally-accessible conductive pins. During the process of manufacturing of the memory module, the individual electronic components are stacked one on top of another such that the pins of every component in a stack are electrically connected together. In other words, the pins for each successively stacked component are connected to the pins of the component on which it is stacked (either directly or through a thin printed circuit board). The stacked components are then connected to the printed circuit board for the memory module.
As can be appreciated, by stacking TSOP electronic components on top of one another, design engineers are able to significantly increase the memory capacity of memory modules without increasing the overall height or length of the module and without compromising the signal speed capabilities of the memory module, which is highly desirable.
However, memory modules of the type described above which include stacked TSOP electronic components suffer from a few notable drawbacks.
As one drawback, memory modules of the type described above which include stacked TSOP electronic components often experience unacceptable signal degradation, which is highly undesirable. Specifically, stacking multiple TSOPs on top of one another creates a significantly long trace length from the TSOP at the top of the stack to the circuit board. As can be appreciated, the increased trace length serves to add inductance and capacitance to the stack which, in turn, unacceptably delays a signal traveling from the stack to the circuit board.
As another drawback, memory modules of the type described above which include stacked TSOP electronic components are considerably greater in width (i.e., thickness), which is highly undesirable. Specifically, stacking electronic components on both sides of a circuit board serves to increase the overall width of the memory module by roughly the increase height of the largest stack on each side of the circuit board. As noted above, due to space constraints, stacking electronic components on both sides of a circuit board often precludes such a memory module from fitting within the space within a computer which is designated for the memory module.
Another technique which is commonly used to increase the memory density of a memory module involves maximizing the number of electronic components which can be fit onto the front and rear surfaces of a standard memory module circuit board.
One well-known method for maximizing the number of electronic components which can be fit onto a circuit board involves the use electronic components which include a ball grid array (BGA) package. Specifically, a BGA package utilizes a plurality of conductive balls mounted on its bottom surface for electrically connecting the die within the package of the electronic component to the circuit board.
The utilization of electronic components which include a BGA package introduces a couple of notable advantages.
As a first advantage, the solder balls which are used to connect the die of the electronic component to the circuit board are connected to the bottom surface of the electronic component package. To the contrary, a dual in-line package utilizes a plurality of leads mounted along the sides of its package for electrically connecting the die of the electronic component to the circuit board. As can be appreciated, by mounting the conductive balls onto the bottom surface of its package, rather than along the sides of its package, the footprint required on the circuit board for each electronic component is significantly reduced. As a result, the number of electronic components which are capable of being mounted onto the circuit board is maximized.
As a second advantage, because the surface area of the bottom surface of the package is traditionally larger than the surface area of the sides of the package, by mounting the solder balls to the bottom surface, the electronic component is able to significantly increase the number of points of electrical contact between the die of the electrical component and the circuit board, which is highly desirable.
Another well-known method for maximizing the number of electronic components which can be fit onto a circuit board involves mounting each electronic component onto the circuit board without any packaging. Specifically, the die of each electronic component is mounted directly onto the circuit board without any packaging. As can be appreciated, with the packaging removed, the footprint of each electronic component is significantly reduced in some cases, thereby enabling more electronic components to be fit on the circuit board, which is highly desirable.
The aforementioned technique of mounting the die of each electronic component directly onto the circuit board without any packaging introduces one notable drawback. Specifically, the lack of packaging for each electronic component renders it incapable of most types of pre-testing (e.g., speed testing, temperature testing, etc.). As a result, if only one package-free electronic component which is mounted on the circuit board is found to be defective, the entire memory module can be significantly compromised. This compromising often necessitates the disposal of the memory module, thereby wasting all of the other properly functioning electronic components mounted on the circuit board. The discarding of a large number of properly functioning electronic components can produce a cost associated yield loss which is unacceptable.
In all of the aforementioned techniques for increasing the memory capacity of a memory module, it is to be understood that each electronic component used comprises only a single memory die which is either encapsulated in within a package or mounted directly onto the circuit board without any packaging.
In certain applications outside of the memory module industry, such as the cell phone and hand-held computer industries, it is known for a pair of different dies, each die uniquely designed to perform a particular function (e.g., a first die for controlling a device, such as a keyboard, and a second die for storing data), to be stacked on top of one another and encapsulated within a single thin small outline package. By encapsulating the pair of application specific dies within a common integrated circuit package, the internal architecture of the system in which said component is used can be considerably simplified.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention relates generally to electronic connectors such as audio and data connectors.
Standard audio connectors or plugs are available in three sizes according to the outside diameter of the plug: a 6.35 mm (¼″) plug, a 3.5 mm (⅛″) miniature plug and a 2.5 mm ( 3/32″) subminiature plug. The plugs include multiple conductive regions that extend along the length of the connectors in distinct portions of the plug such as the tip, sleeve and one or more middle portions between the tip and sleeve resulting in the connectors often being referred to as TRS (tip, ring and sleeve) connectors.
FIGS. 1A and 1B illustrate examples of audio plugs 10 and 20 having three and four conductive portions, respectfully. As shown in FIG. 1A, plug 10 includes a conductive tip 12, a conductive sleeve 16 and a conductive ring 14 electrically isolated from the tip 12 and the sleeve 16 by insulating rings 17 and 18. The three conductive portions 12, 14, 16 are for left and right audio channels and a ground connection. Plug 20, shown in FIG. 1B, includes four conductive portions: a conductive tip 22, a conductive sleeve 26 and two conductive rings 24, 25 and is thus sometime referred to as a TRRS (tip, ring, ring, sleeve) connector. The four conductive portions are electrically isolated by insulating rings 27, 28 and 29 and are typically used for left and right audio, microphone and ground signals. As evident from FIGS. 1A and 1B, each of audio plugs 10 and 20 are orientation agnostic. That is, the conductive portions completely encircle the connector forming 360 degree contacts such that there is no distinct top, bottom or side to the plug portion of the connectors.
When plugs 10 and 20 are 3.5 mm miniature connectors, the outer diameter of conductive sleeve 16, 26 and conductive rings 14, 24, 25 is 3.5 mm and the insertion length of the connector is 14 mm. For 2.5 mm subminiature connectors, the outer diameter of the conductive sleeve is 2.5 mm and the insertion length of the connector is 11 mm long. Such TRS and TRRS connectors are used in many commercially available MP3 players and smart phones as well as other electronic devices. Electronic devices such as MP3 players and smart phones are continuously being designed to be thinner and smaller and/or to include video displays with screens that are pushed out as close to the outer edge of the devices as possible. The diameter and length of current 3.5 mm and even 2.5 mm audio connectors are limiting factors in making such devices smaller and thinner and in allowing the displays to be larger for a given form factor.
Many standard data connectors are also only available in sizes that are limiting factors in making portable electronic devices smaller. Additionally, and in contrast to the TRS connectors discussed above, many standard data connectors require that they be mated with a corresponding connector in a single, specific orientation. Such connectors can be referred to as polarized connectors. As an example of a polarized connector, FIGS. 2A and 2B depict a micro-USB connector 30, the smallest of the currently available USB connectors. Connector 30 includes a body 32 and a metallic shell 34 that extends from body 32 and can be inserted into a corresponding receptacle connector. As shown in FIGS. 2A, 2B, shell 34 has angled corners 35 formed at one of its bottom plates. Similarly, the receptacle connector (not shown) with which connector 30 mates has an insertion opening with matching angled features that prevents shell 34 from being inserted into the receptacle connector the wrong way. That is, it can only be inserted one way—in an orientation where the angled portions of shell 34 align with the matching angled portions in the receptacle connector. It is sometimes difficult for the user to determine when a polarized connector, such as connector 30 is oriented in the correct insertion position.
Connector 30 also includes an interior cavity 38 within shell 34 along with contacts 36 formed within the cavity. Cavity 38 is prone to collecting and trapping debris within the cavity which may sometimes interfere with the signal connections to contacts 36. Also, and in addition to the orientation issue, even when connector 30 is properly aligned, the insertion and extraction of the connector is not precise, and may have an inconsistent feel. Further, even when the connector is fully inserted, it may have an undesirable degree of wobble that may result in either a faulty connection or breakage.
Many other commonly used data connectors, including standard USB connectors, mini USB connectors, FireWire connectors, as well as many of the proprietary connectors used with common portable media electronics, suffer from some or all of these deficiencies or from similar deficiencies.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention improves upon the loss characteristics of an optical waveguide and related measurement system of the kind described in U.S. patent application Ser. No. 10/868,475, filed Jun. 15, 2004, “Apparatus For Optical Measurements On Low-Index Non-Solid Materials Based On Arrow Waveguides”, which is hereby incorporated by reference in its entirety. This application was published on Dec. 16, 2004, with Publication Number US20040252957A1.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Hinges are subject to weathering, daily wear and abuse over the years, leading to eventual failure. Outdoors they rust and are subject to being removed for unauthorized entry by the simple expediency of pulling the pins. When the pins are removed or stolen, they are often replaced by nails or other stop-gap means, resulting in their less than optimal performance.
Most outdoor hinges do not have a self-closing feature, and most that do close with a weighted rope on a pulley or with a spring. The vast majority of gates and even more doors have lo no self-closing feature at all despite the many cases in which clearly either the open or the closed position should be established as the default mode, especially when infants and small children are about.
Hinges have been designed which are self-closing, and there are also hinges assembled from two identical halves. Most require a separate hinge pin and some have structure which avoids the use of a pin. However, often these are not designed for outdoor use, and no known one-piece hinge is automatically self-closing
Some are made of plastic or nylon rather than metal, and thus avoid the corrosive effects of weather over time. By and large however, they require the use of additional structure to make a complete unit, such as a hinge pin or a clip to hold the halves together. Or, alternatively there is a one-piece hinge of the "living hinge" variety, having a limited life as at the bend line of the material is repeatedly worked back and forth until it parts.
There is a need for a weatherproof, durable, simply and rugged hinge made from two identical parts that require the use of no additional structure, the two parts of which axially migrate with respect to one another when mutually rotated such that a swing-closed feature is inherent in the design without additional components.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Peracid compositions have been reported to be effective antimicrobial agents. Methods to clean, disinfect, and/or sanitize hard surfaces, meat products, living plant tissues, and medical devices against undesirable microbial growth have been described (U.S. Pat. No. 6,545,047; U.S. Pat. No. 6,183,807; U.S. Pat. No. 6,518,307; U.S. patent application publication 20030026846; and U.S. Pat. No. 5,683,724). Peracids have also been reported to be useful in preparing bleaching compositions for laundry detergent applications (U.S. Pat. No. 3,974,082; U.S. Pat. No. 5,296,161; and U.S. Pat. No. 5,364,554).
Peracids can be prepared by the chemical reaction of a carboxylic acid and hydrogen peroxide (see Organic Peroxides, Daniel Swern, ed., Vol. 1, pp 313-516; Wiley Interscience, New York, 1971). The reaction is usually catalyzed by a strong inorganic acid, such as concentrated sulfuric acid. The reaction of hydrogen peroxide with a carboxylic acid is an equilibrium reaction, and the production of peracid is favored by the use of an excess concentration of peroxide and/or carboxylic acid, or by the removal of water.
Enzyme catalysts can also catalyze the rapid production of peracid at the time of use and/or application, avoiding the need for storage of peracid solutions, which may cause peracid concentration to decrease over time. The high concentrations of carboxylic acids typically used to produce peracid via the direct chemical reaction with hydrogen peroxide are not required for enzymatic production of peracid, where the enzyme-catalyzed reaction can use a carboxylic acid ester as substrate at a much lower concentration than is typically used in the chemical reaction. The enzyme-catalyzed reaction can be performed across a broad range of pH, depending on enzyme activity and stability at a given pH, and on the substrate specificity for perhydrolysis at a given pH.
Esterases, lipases and some proteases have the ability to catalyze the hydrolysis of alkyl esters to produce the corresponding carboxylic acids (Formula 1):
Some esterases, lipases, and proteases also exhibit perhydrolysis activity, catalyzing the synthesis of peracids from alkyl esters (Formula 2):
The CE-7 class of carbohydrate esterases has been found to have highly specific activity for perhydrolysis of esters, particularly acetyl esters of alcohols, diols and glycerols. U.S. patent application Ser. Nos. 11/638,635; 11/743,354; 11/943,872; and 12/143,375 to DiCosimo et al. disclose enzymes structurally classified as members of the CE-7 family of carbohydrate esterases (e.g., cephalosporin C deacetylases [CAHs] and acetyl xylan esterases [AXEs]) that are characterized by significant perhydrolysis activity for converting carboxylic acid esters (in the presence of a suitable source of peroxygen, such as hydrogen peroxide) into peroxycarboxylic acids at concentrations sufficient for use as a disinfectant and/or a bleaching agent. Under certain reaction conditions, CE-7 esterases can catalyze the production of concentrations of peracid at least as high as 4000-5000 ppm in 1 min and up to at least 9000 ppm in 5 min to 30 min (U.S. patent application Ser. No. 12/143,375 to DiCosimo et al.). Peroxycarboxylic acids can be corrosive to certain metal surfaces, however, so it may be desirable to limit the total amount of peracid produced during the reaction to prevent or minimize the corrosive effect of the resulting solution. For example, applications that require production of no more than 200 ppm to 1000 ppm of peracid in 1 minute often employ reaction conditions that yield a final concentration of peracid well above these limits. In an application for in situ generation of peracid for disinfection of hard surfaces, it is desirable to have the ability to rapidly generate the desired concentration of peracid without significantly exceeding the upper efficacious disinfectant concentration, thereby limiting or preventing the corrosion of certain components of the surface. In an application for in situ generation of peracid for bleaching of laundry or textiles, similar limitations to the concentration of peracid generated above that required for bleaching are also desirable.
In addition to catalyzing the production of peracids, CE-7 esterases can also catalyze the hydrolysis of peracid to produce carboxylic acid and hydrogen peroxide. Therefore, under reaction conditions where the enzyme retains its activity for an extended period of time, it may destroy the peracid produced in the first enzyme-catalyzed reaction of ester and peroxide, producing carboxylic acid (e.g., acetic acid) as a byproduct that can impart an undesirable odor to the disinfectant solution. This peracid hydrolysis activity of the enzyme could also jeopardize the long term stability of peracid-containing formulations produced by CE-7 esterases over the course of several hours, or even several days or weeks, depending on the stability of the peracid in the disinfectant formulation.
Peracid solutions have a wide variety of applications. Though progress has been made in devising efficient and effective ways to produce peracid solutions, improved methods are needed. An in situ process for producing peracids that limits the enzyme-catalyzed production of peracids in a peracid concentration-dependent manner would allow targeted concentrations of peracids to be produced in a task-appropriate way.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Synthetic porphyrins and metalloporphyrins have become increasingly important in numerous and diverse technical fields. Their several practical applications include their use as sensitizers in photodynamic therapy (PDT) (Mody, (2000) J. Porphyrins Phthalocyanines 4: 362); in electron transfer (Lippard and Berg, (1994) Principles of Bioinorganic Chemistry, University Science Book: Mill Valley, Calif.); in DNA strand cleavage (Bennett et al., (2000) Proc. Natl. Acad. Sci. 97: 9476; Hashimoto et al., (1983) Tetrahedron Letters, 24: 1523); as carriers of cytotoxic anticancer drugs such as platinum (Song et al., (2002) Inorganic Biochemistry 83: 83; and Lottner et al., (2002) J. Med. Chem., 45, 2064); as components of synthetic receptors (Jain and Hamilton, (2002) Org. Lett. 2: 1721); and as oxidation catalysts (Guo et al., (2001) J. Mol. Catal. A Chem. 170: 43). Additionally, functionalized porphyrins have become important leads in current drug discovery techniques (See Mody, supra, and Priola et al., (2002) Science 287: 1503). Accordingly, the development of new methodologies and strategies to improve the synthesis of functionalized porphyrins has become highly desirable.
Numerous methods for the synthesis of porphyrins are known. The classical methods for porphyrin synthesis typically require harsh reaction conditions and can provide disappointingly low yields (Rothemund, (1935) J. Am. Chem. Soc., 57: 2010; Adler et al., (1967) J. Org. Chem. 32: 476). Newer methodologies, such as those developed by Lindsey and colleagues, have resolved certain issues regarding reaction conditions and yields (Lindsey et al., (1987) J. Org. Chem. 52: 827). More recently, transition metal-catalyzed organic synthesis methodologies (e.g., Suzuki coupling, Heck-type coupling, and Stille cross coupling), have been successfully employed with porphyrin systems, providing versatile and general synthetic approaches for the preparation of a variety of functionalized porphyrins and porphyrin analogs. See, e.g., DiMagno et al., (1993) J. Org. Chem., 58: 5983; DiMagno et al., (1993) J. Am. Chem. Soc. 115: 2513; Chan et al., (1995) Tetrahedron 51: 3129; Zhou et al., (1996) J. Org. Chem. 61: 3590; Risch and Rainer, (1997) Tetrahedron Letters 38: 223; Hyslop et al., (1998) J. Am. Chem. Soc. 120:12676; Boyle and Shi, (2002) J. Chem. Soc. Perkin Trans., 1: 1397; and Pereira et al., (2002) J. Chem. Soc. Perkin Trans., 2: 1583. See also, Suzuki, (1998) Metal-Catalyzed Cross-Couplinq Reactions, pp. 49-97, Wiley-VCH, Weinheim, Germany; Liu et al., (1998) J. Chem. Soc., Dalton Trans. 1805; Shi et al., (2000) J. Org. Chem. 65: 1650; Shanmugathasan et al., (2000) Porphyrins Phthalocyanines 4: 228; Lovine et al., (2000) J. Am. Chem. Soc. 122: 8717; Deng et al., (2000) Angew. Chem. Int. Ed. 39: 1066; and Chang et al., (2003) J. Org. Chem. 68: 4075; U.S. Pat. No. 5,550,236 and U.S. Pat. No. 5,756,804, which references are incorporated herein by reference. Further, porphyrin synthesis via palladium-catalyzed C—N bond formation, see Khan et al., (2001) Tetrahedron Lett. 42: 1615; Takanami et al., (2003) Tetrahedron Lett. 44: 7353, and metal-mediated C—C bond formation, see Sharman et al., (2000) Porphyr. Phthalocyanines 4: 441, has been reported.
Each of these foregoing methods, however, possesses undesirable aspects that should be mitigated, including incompatibilities between catalysts and reaction compounds, low turnover number (TON) and low turnover frequency (TOF). Thus, despite recent advances in porphyrin chemistry, a need still exists for facile and general syntheses for, in particular, heteroatom-substituted porphyrins and metalloporphyrins.
More particularly, a need exists for facile and general syntheses for heteroatom-substituted chiral porphyrins. Chiral porphyrins have found a range of applications in many areas, such as asymmetric catalysis, chiral recognition/sensing, and enzymatic mimicry. Of particular interest is the use of chiral porphyrins in asymmetric catalysis.
Biologically relevant porphyrins are among the most versatile ligands for transition metal complexes. See Brothers, (2001) Adv. Organometallic Chem. 46:223; Brothers, (2001) Adv. Organometallic Chem. 48: 289. Metalloporphyrins have found a diverse array of applications in areas ranging from chemistry to biology and from materials to medicine. Metalloporphyrins are known to catalyze a range of fundamentally and practically important chemical transformations, including an array of atom/group transfer reactions, such as oxene (epoxidation and hydroxylation), nitrene (aziridination and amination), and carbene (cyclopropanation and carbene insertion) transfers, that allow the direct conversion of abundant and inexpensive alkenes and alkanes into functional molecules. See The Porphyrin Handbook; Kadish, K. M., Smith, K. M., Guilard, R., Eds., Academic Press: San Diego, 2000-2003; Metalloporphyrins in Catalytic Oxidations; Sheldon, R. A., Ed.; Marcel Dekker: New York, 1994; Metalloporphyrins Catalyzed Oxidations: Montanari, F., Casella, L., Eds., Kluwer Academic Publishers: Boston, 1994. Due to the unique ligand environment and metal coordination mode of metalloporphyrins, unusual reaction selectivities and excellent catalyst turnovers have been observed for metalloporphyrin-based catalysts. Thus, there is a significant interest in designing and synthesizing chiral porphyrins for developing asymmetric versions of the abovementioned catalytic processes.
Since the first application of a chiral iron porphyrin complex for catalytic asymmetric epoxidation, see Groves et al., (1983) J. Am. Chem. Soc. 105: 5791, a number of chiral porphyrins have been synthesized as potential asymmetric catalysts. See Marchon, (2003) in The Porphyrin Handbook; supra, Vol. 11, pp 75-132; Simonneaux et al., (2002) Coord. Chem. Rev. 228: 43; Rose et al., (2000) Polyhedron 19: 581; Collman et al., (1999) Chemtracts 12: 299; Rose et al., (1998) Coord. Chem. Rev. 178-180: 1407; Collman et al., (1993) Science 261: 1404; Rose et al., (2004) Chem. Eur. J. 10: 224. Although significant progress has been made in this area, catalytic reactions based on metalloporphyrins have not been developed into practical methodologies that can be used in asymmetric synthesis. This lack of development can be attributed mainly to the expense and difficulty associated with chiral porphyrin synthesis.
Several approaches have been applied to chiral porphyrin synthesis. See Marchon, supra, Rose et al., (2000), supra, and Collman et al., (1993), supra. The most general and chirally economic scheme for synthesizing chiral porphyrins is to covalently attach suitable chiral building blocks to a preformed porphyrin synthon comprising peripheral functional groups. See Tani et al., (2002) Coord. Chem. Rev. 226: 219; Simonneaux et al., supra; Collman et al., (1999), supra; Rose et al., (1998), supra; Boschi, in Metalloporphyrins Catalyzed Oxidations: Montanari, F., Casella, L., Eds., Kluwer Academic Publishers: Boston, 1994; pp 239-267; and Naruta, (1994) in Metalloporphyrins in Catalytic Oxidations; Sheldon, R. A., Ed.; Marcel Dekker: New York, pp 241-259.
Representative porphyrin synthons that have been found to be useful for synthesizing chiral porphyrins include meso-tetrakis(o-aminophenyl)porphyrin (See Collman et al., (1975) J. Am. Chem. Soc. 97: 1427 and Leondiadis et al., (1989) J. Org. Chem. 54: 6135), meso-tetrakis(2,6-diaminophenyl)porphyrin (see Rose et al., (1996) J. Am. Chem. Soc. 118: 1567), meso-tetrakis (2,6-dihydroxyphenyl)porphyrin (see Collman et al., (1997) Inorg. Synth. 31: 117 and Tsuchida et al., (1990) J. Chem. Soc.-Dalton Trans. 2713), and meso-tetrakis(2,6-dicarboxyphenyl)porphyrin (ee Nakagawa et al., (2001) Org. Lett. 3: 1805). These synthons allow the attachment of chiral acids, chiral amines, or chiral alcohols through amide or ester bond formation. To enhance the synthetic utility and flexibility of metalloporphyrin-based asymmetric catalysis, it is desirable to develop alternative synthons for the versatile construction of chiral porphyrins that could be employed in practical asymmetric catalysis.
Within this context, halogenated porphyrins, e.g., bromoporphyrins, have been shown to be versatile precursors for the synthesis of heteroatom-functionalized porphyrins via metal-catalyzed carbon-heteroatom cross-coupling reactions with soft, non-organometallic nucleophiles. See Chen et al., (2003) J. Org. Chem. 68: 4432; Gao et al., (2003) J. Org. Chem. 68: 6215; Gao et al., (2003) Org. Lett. 5: 3261; and Gao et al., (2004) Org. Lett. 6: 1837. These methods are based on metal-catalyzed carbon-heteroatom bond formations. See Lev et al., (2003) Angew. Chem.-Int. Edit. 42: 5400; Prim et al., (2002) Tetrahedron, 58: 2041; Muci et al., (2002) Top. Curr. Chem. 219: 131; Hartwig, (2002) in Handbook of Organopalladium Chemistry for Organic Synthesis; Negishi, E., Ed.; Wiley-Interscience: New York, pp 1051; Yang et al., (1999) J. Organomet. Chem. 576: 125; Wolfe et al., (1998) Acc. Chem. Res. 31: 805; Hartwig, (1998) Angew. Chem.-Int. Edit. 37: 2047; and Hartwig, (1997) Synlett, 329. Such syntheses can be performed under mild conditions with a wide range of nucleophiles, including amines, amides, alcohols, and thiols, leading to a family of novel porphyrins comprising otherwise inaccessible heteroatom functionalities in high yields.
For example, a general and efficient method has been developed for the synthesis of meso-arylamino- and meso-alkylamino-substituted porphyrins from reactions of meso-bromoporphyrins with amines. See Chen et al., (2003) J. Org. Chem. 68: 4432. Similar methodology also can be effectively applied to brominated diphenylporphyrins and tetraphenylporphyrins, leading to the versatile synthesis of porphyrin derivatives bearing multiple arylamino and alkylamino groups. See Gao et al., (2003) J. Org. Chem. 68: 6215. In addition, a convenient and general approach has been developed for the synthesis of meso-aryloxy- and meso-alkoxy-substituted porphyrins from reactions with alcohols via palladium-catalyzed etheration. See Gao et al., (2003) Org. Lett. 5: 3261. A general synthetic method for meso-amidoporphyrins from reactions with amides via palladium-catalyzed amidation also has been developed. See Gao et al., (2004) Org. Lett. 6: 1837. Expanding the synthetic strategy to palladium-mediated carbon-sulfur bond formation, a versatile procedure also has been developed for the synthesis of meso-arylsulfanyl- and mesoalkylsulfanyl-substituted porphyrins from reactions of the corresponding bromoporphyrin precursors and thiols. See Gao et al., (2004), submitted for publication. There exists, however, a need in the art for improved methods for the synthesis of heteroatom-substituted chiral porphyrins.
Accordingly, the presently disclosed subject matter describes the use of haloporphyrins as a new class of synthons for the versatile syntheses of chiral porphyrins via metal catalyst-mediated carbon-heteroatom bond formation reactions with chiral nucleophiles, such as chiral amines, chiral amides, chiral alcohols, and chiral thiols, and the use of these chiral porphyrins as catalysts in asymmetric cyclopropanation, asymmetric aziridination, and asymmetric epoxidation reactions.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The invention relates to a sampling and infusion connector for an extracorporeal blood circulation line.
2. Description of the Related Art
As is known, lines for circulating blood outside the body, such as those used in a dialysis apparatus, need at least one connector for attachment to a blood line, the connector having a port for sampling blood and/or for infusing liquids into the blood flow. The flow is controlled by a pump, preferably peristaltic, which acts via rollers or the like on a flexible duct portion of the line.
A known connector for an aforementioned line comprises a tubular body having a blood inlet, an infusion opening, and a sampling opening located between the blood inlet and the infusion opening, the sampling opening for permitting test quantities of blood to be withdrawn such as through a syringe. This related art arrangement has the disadvantage that, during sampling, the infusion liquid tends to be sucked back in counter-current by the negative pressure caused by the sampling syringe, thereby mixing with the sampled blood and altering its composition.
Thus, in the related art, in order to prevent the infusion liquid from reaching the sampling aperture at the moment when suction is exerted by the syringe, it is necessary to interrupt the infusion process for a period of time, which can cause adverse effects on the treatment. Alternatively, the connector could be constructed so that the sampling aperture is disposed at an appreciable distance from the infusion aperture, in which case the connector would be bulky and inconvenient to use.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Field of the Invention
The invention relates to a digital signal processing device, particularly for applications as an ADPCM codec.
Particularly for mobile communications, codecs are currently needed that carry out data reduction by half as compared with earlier codecs. One familiar method of data reduction is the ADPCM algorithm, which has already been standardized under CCITT Standard G.721 for a long time. One special feature of that algorithm is that only a very few multiplications and buffer storage operations are needed. Essentially, the only operations that have to be carried out are shift and addition operations and data format conversions, that is conversions from fixed point to floating point representation and vice versa. Modern codecs should also enable convenient sound generation and offer a certain flexibility in implementation of additional functions.
Heretofore either standard signal processors or specially customized logic circuits were used to achieve codec functions. Typical multipurpose signal processor architectures currently being used are optimized for rapid execution of multiplication and buffer storage operations, but are less suitable for the ADPCM algorithm. In particular, format conversions and additional functions such as sound generation, echo compensation and so forth can be implemented only with comparatively great difficulty. Furthermore, the very powerful command set in a multipurpose signal processor is far from being fully exploited. That structure is accordingly not optimal from the standpoint of cost and power consumption. In that respect, structures with specially customized logic circuits are more favorable. However, they only offer very slight flexibility in terms of implementing additional functions.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
There are basically two different types of heart valve prostheses: Prostheses comprising mechanical valves, which are artificially produced, usually being made of graphite coated with pyrolytic carbon, and prostheses comprising valves made of biological tissue, usually pericardial tissue, which is usually obtained from animal sources (e.g. swine or cattle). The heart valve formed of biological tissue is usually mounted in a base body (e.g. a rigid plastic framework or a self-expanding stent), which is then implanted at the position of the natural valve. The present invention describes a method for preparing such tissue for use in a heart valve prosthesis for implantation at the site of a natural heart valve.
The tissue of origin must be thoroughly cleaned and prepared before implantation. In so doing, the tissue is modified, to the greatest extent possible, such that the tissue is not recognized by the body as foreign tissue, is not calcified, and has the longest life span possible. Such a method for preparing tissue substantially comprises at least two main steps having a plurality of intermediate rinsing processes.
The first essential preparation step is the so-called decellularization of the tissue. In this step, cell membranes, intracellular proteins, cell nuclei, and other cellular components are removed as completely as possible from the tissue in order to obtain the purest extracellular matrix possible. Any cells and cellular components remaining in the tissue would be potent crystal nuclei, in particular, for an unwanted calcification of the biological implant material. The decellularization, as a washing step, should be performed in a manner that is so gentle that the structure and the collagen fibers in the extracellular matrix remain as unaffected as possible while ensuring that all cells contained therein are thoroughly removed from the tissue.
The second essential preparation step is that of cross-linking the tissue, in particular the collagen fibers. After decellularization, preferably all cellular components have been removed from the tissue and the biological material nearly exclusively comprises the extracellular matrix. In the case of pericardial tissue, the extracellular matrix is formed primarily of collagen fibers. In order to obtain biological material having the most optimal mechanical properties possible and to prevent rejection reactions by the receiving body, the collagen fibers are cross-linked by means of a suitable cross-linking agent via the incorporation of chemical bonds. The cross-linking agent binds to the amino groups of the collagen fibers and forms chemically stable compounds between collagen fibers. A biological material having long-term stability is thereby obtained from the three-dimensionally arranged collagen fibers, wherein this biological material is no longer recognized as foreign biological material. The stability and strainability of the tissue is markedly increased by means of the three-dimensional cross-linking or linking of the individual collagen fibers via the cross-linking agent. This is decisive, in particular, in the case of use as tissue of a heart valve, where the tissue must open and close, in brief intervals, as a valve.
An alternative method for preparing biological tissue is described in WO 2004/052417. In this method according to the prior art, the tissue is decellularized with a 1-2% deoxycholic acid solution. After a plurality of rinsing steps, the tissue is conditioned in a solution containing a cyclic lipopeptide. The cyclic lipopeptide surfactin is used, in particular, as the conditioning agent after decellularization is completed and before repopulation with cells. In this alternative method according to the prior art, cross-linking of the collagen fibers is not performed using a suitable cross-linking agent. After conditioning, the tissue is populated with natural cells.
WO 2011/109433 discloses a method for preparing biological tissue, wherein distilled water is used for decellularization. Glutaraldehyde functions as the cross-linking agent in a subsequent step.
WO 2005/118014 discloses the use of a first ionic detergent and a second non-ionic detergent for decellularization. In this case, an anionic detergent such as sodium dodecyl sulfate or sodium dodecyl sulfonate is preferably provided as the first ionic detergent. As an alternative, bile acids such as sodium cholate or sodium deoxycholate can be used as the first detergent. The second detergent is electrically neutrally charged, such as a detergent containing polyethylene glycol.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The vehicle platooning, which has recently attracted great attention, is a method of driving multiple vehicles in a line. Specifically, the multiple vehicles are connected to each other through a Vehicle-to-Vehicle (V2V) communication, which is one kind of a Vehicle-to-Everything (V2X), and drive safely while maintaining distances between themselves by the aid of at least one leading vehicle capable of controlling steerings, accelerators, and brakes of following vehicles.
The vehicle platooning may have many advantages. For example, the vehicles can improve fuel efficiencies with lower air resistance and thereby reduce the exhaust emission. Further, the multiple vehicles may comply with traffic regulations and thereby there may be an increase in efficiency of road management.
However, the vehicle platooning may also have some disadvantages incurred because the multiple vehicles should drive in company with various kinds of vehicles such as semi-autonomous vehicles and general vehicles as well as autonomous vehicles on the road. For example, the vehicle platooning may not be available occasionally according to certain conditions. Also, in the case drivers should check such conditions, higher possibility of accidents and inefficiency of the vehicle platooning may be incurred.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
This invention relates to an LIF connector having an LIF (low insertion force) mechanism by which a multi-pole connector, having many terminals, can be easily inserted into and withdrawn from a mating connector.
The term "connector", used in this specification of the present invention, means a connector including at least male terminals or female terminals, and a housing receiving these terminals therein, and the housing may be either separate from or integral with other member.
A multi-pole connector has a plurality of terminals, and therefore a large insertion/withdrawal force is required for inserting and withdrawing the connector relative to a mating connector, and it has been rather difficult to effect the insertion and withdrawal of the connector. In view of the difficulty of insertion and withdrawal of such a multi-pole connector, there have now been proposed various connectors (LIF connectors) having an LIF mechanism.
A representative example of such conventional LIF connectors includes one in which a connector is inserted and withdrawn by operating a slider.
One such conventional slider-type LIF connector is proposed in Japanese Patent Unexamined Publication No. Hei. 4-319271. FIG. 1 is an exploded, perspective view of the LIF connector disclosed in Japanese Patent Unexamined Publication No. Hei. 4-319271.
This LIF connector comprises a plurality of connectors 211 and 212, a rectangular frame-like holder 220 for receiving these connectors 211 and 212, a mating connector 230 for receiving the connectors 211 and 212 received in the holder 220, and a slider 240 of a generally U-shape for inserting and withdrawing the connectors 211 and 212 relative to the connector 230.
A pair of guide pins 221 and 221 are formed on each of upper and lower surfaces of the holder 220, and insertion holes 231 and 231 for the slider 240 are formed respectively through opposite end walls of the mating connector 230, and a pair of cam grooves 241 and 241, corresponding to the projections 221 and 221, are formed in each of upper and lower walls of the slider 240.
In the LIF connector of the above construction, the slider 240 is inserted into a predetermined position in the mating connector 230, and the guide pins 221 on the holder 220 are positioned respectively relative to the cam grooves 241 in the slider 240. Then, when the slider 240 is pushed into the mating connector 230, the guide pins 221 on the holder 220 move respectively along the cam grooves 241 in the slider 240, so that the connectors 211 and 212, received in the holder 220, are inserted into the mating connector 230.
Namely, in this LIF connector, by merely pushing the slider 240, the connectors 211 and 212 can be easily fitted into the mating connector 230.
However, in the above conventional slider-type LIF connector, the slider has a symmetrical configuration, and there have been occasions when the slider 240 has been inserted into the mating connector 230 in an inverted manner (that is, upside down), as indicated in dots-and-dash lines in FIG. 1.
The above conventional LIF connector is not provided with any means for preventing such inverted insertion of the slider 240, and the only way to prevent the inverted insertion of the slider 240 has been to confirm the direction of the cam grooves 241 with the eyes.
However, in order to find the inverted insertion of the slider 240 from the direction of the cam grooves 241, it is necessary first to understand the proper direction of the cam grooves 241, and then to judge whether or not the actual direction of the cam grooves 241 is proper.
The cam grooves 241 are formed in the inner side of the slider 240, and it has been difficult to recognize these cam grooves with the eyes. Particularly when the LIF connector is mounted within a vehicle body, it has been extremely difficult to see the thin cam grooves 241 in the dark.
Therefore, in the conventional slider-type LIF connector, the inverted insertion of the slider 240 has been noticed at the time when trying to engage each guide pin 221 on the holder 220 in an opening 241a of the associated cam groove 241.
Even in this case, each guide pin 221 and the associated opening 241a sometimes could not be properly positioned with respect to each other, and hence could not be engaged with each other, and therefore after all, the condition of the slider 240 was first confirmed with the eyes, and then the inverted insertion of the slider 240 could be realized.
Therefore, when the slider 240 was inserted in an inverted manner, much time was required before realizing this fact, and there was encountered a problem that the connectors 211 and 212 could not be inserted into the mating connector 230.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Comfort and effectiveness remain a continuing challenge for engineers and designers of the interface between a mechanical ventilator and a patient. Such patient interfaces are currently employed for a variety of purposes including the delivery of non-invasive ventilation or for the delivery of pressurized air to persons who suffer from sleep disordered breathing conditions such as Obstructive Sleep Apnea (OSA). In non-invasive positive pressure ventilation, a supply of air at positive pressure is provided by a blower to a patient interface through an air delivery conduit. The patient interface may take the form of a nasal mask, nose & mouth mask, full face mask or nasal prongs.
A mask may comprise (i) a rigid or semi-rigid portion which attaches directly to the air delivery conduit and (ii) a soft patient contacting portion. The rigid or semi-rigid portion, known as a shell or frame, may define a nose-receiving cavity, or a mouth covering chamber. Other forms of patient interface, such as nasal cannulae, comprise a pair of nasal prongs, nasal inserts or nozzles.
The soft patient contacting portion is typically known as a cushion or membrane and is generally shaped during manufacture to match the facial contours of a patient in order to provide the optimum seal.
An inherent characteristic of patient interfaces such as nasal masks or nozzle assemblies is that they do not seal the mouth region. A number of patients thus find that during sleep when muscles relax, mouth leak may occur. Alternatively some patients are naturally mouth breathers and thus find a nasal patient interface ineffective. Mouth leak is undesirable as among other difficulties, it may result in noise, increased treatment pressure to compensate for the leak or an increased load on the nasal passages and potentially nasal obstruction or a runny nose.
Patient interfaces such as full face masks or nose and mouth masks address this issue by sealing around both the nose and the mouth. Since nasal bridge anthropometry varies greatly between patients, the soft patient contacting portion or cushion must adapt to the shapes of individual patients. Typically this is not achieved for the entire range of patients and some form of leak occurs. The problem is heightened during sleep when the jaw moves and the head position changes. This action can often serve to dislodge the mask and cause leak. Since leak can be noisy and results in less-effective treatment, users often compensate by tightening the headgear more than is required. This is detrimental for patient comfort and can cause skin breakdown.
A further problem encountered by patients who are using full face, nasal or nose and mouth masks is that the portion of the patient interface that seals around the nasal bridge prevents the patient from wearing spectacles. Additionally it may give the sensation of being closed in, leading to a feeling of claustrophobia, particularly when combined with a mouth-sealing portion. A further disadvantage is that any leaks that may occur can affect the sensitive area surrounding the eyes.
One form of nasal assembly known as a nasal puff is described in U.S. Pat. No. 4,782,832 (Trimble et al.). This device has a pair of nasal puffs together with a plenum chamber held in place with a harness assembly adapted to be worn over the head of the patient. The device does not provide a mouth seal.
Another form of known nozzle assembly is described in U.S. Pat. No. 6,431,172 (Bordewick et al.). The patent discloses a device with nares elements mounted on an inflatable plenum chamber. Again this does not provide any structure for sealing the mouth.
One typical example of a known nasal mask is described in U.S. Pat. No. 5,243,971 (Sullivan et al.). This has a ballooning seal in order to fit the patient's nose and facial contours but does not provide a mouth seal. The contents of this patent are hereby incorporated by cross-reference.
WO 01/97893 A1 (Frater et al.), the content of which is hereby incorporated by cross-reference, describes a mask system for delivering air to a user including a suspension mechanism. This suspension mechanism allows relative movement between a face-contacting portion and a mask shell.
A known example of a full face mask is described in U.S. Pat. No. 6,513,526 B2 (Kwok et al.), incorporated herein by reference in its entirety. Whilst providing a facial contour and sealing mechanism that incorporates both the nasal and mouth, this mask cannot flex to adapt to changes in jaw movement and head position throughout the night.
A known example of a nose and mouth mask is described in U.S. Pat. No. 5,560,354 (Berthon-Jones et al.), the content of which is hereby incorporated by cross-reference.
U.S. Patent Application Publication 2002/0069872 A1 (Gradon et al.) describes a mouthpiece which seals the oral cavity against ‘mouth leak’. This mouthpiece includes both intra-oral and extra-oral sealing means and can be kept in place without the need for straps. WO 01/95965 (Gradon et al.) describes a similar mouthpiece for supplying humidified gases to a user.
U.S. Pat. No. 6,571,798 B1 (Thornton) describes an oral device for improving a patient's breathing together with a connecting post that provides a standard interface to a CPAP patient interface. The oral device is said to extend the lower jaw of the patient and thus open the breathing passage. The oral device is clenched between the teeth which may lead to discomfort and if mask pressures are high can lead to the slow creep of gums around the teeth due to the sustained load.
U.S. Pat. No. 1,873,160 (Sturtevant) describes a cylindrical air chamber held in position by a mouth portion that extends between the lips and teeth. The mouth portion may prove irritating and lead to discomfort when used for long periods.
A problem with patient interfaces which incorporate oral appliances is that they can be uncomfortable for patients. Therefore, a need has developed in the art to address the problems of the prior art.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Shift registers are core circuit units of driving circuits that are used in products such as thin film transistor liquid crystal displays (TFT-LCDs). A shift register provides sequential pulse signals to scanning lines of a TFT LCD, so as to switch on or switch off TFTs connected to the corresponding scanning lines. Generally, a shift register includes a plurality of shift register units.
Referring to FIG. 5, this is a circuit diagram of a shift register unit 100 of a typical shift register. The shift register unit 100 includes a first clock inversion circuit 110, an inverter 120, and a second clock inversion circuit 130. All transistors in the first clock inversion circuit 110, the inverter 120, and the second clock inversion circuit 130 are PMOS (P-channel metal oxide semiconductor) transistors. The first clock inversion circuit 110 receives a signal VS output from a pre-stage shift register unit (not shown). The signal VS functions as a start signal of the shift register unit 100.
The first clock inversion circuit 110 includes a first transistor M1, a second transistor M2, a third transistor M3, a fourth transistor M4, a first output VO1, and a second output VO2. The first transistor M1 includes a gate for receiving the start signal VS, a source coupled to a first voltage (VDD) such as a power voltage, and a drain coupled to a source of the second transistor M2. The second transistor M2 includes a gate and a drain both coupled to a second voltage (VSS) such as a grounding voltage. The third transistor M3 includes a source coupled to the source of the second transistor M2, a drain serving as the first output VO1, and a gate coupled to a gate of the fourth transistor M4. The gates of the third and fourth transistors M3 and M4 cooperatively serve as a first control terminal to receive a clock signal TS. The fourth transistor M4 includes a source coupled to the start signal VS, and a drain serving as the second output VO2.
The inverter 120 includes a fifth transistor M5 and a sixth transistor M6. The inverter 120 outputs an output signal that serves as the shift register signal VO. The fifth transistor M5 includes a source coupled to the first voltage VDD, a gate coupled to the drain of the third transistor M3, and a drain coupled to a source of the sixth transistor M6. The drain of the fifth transistor M5 and the source of the sixth transistor M6 serve as an output for outputting the shift register signal VO. The sixth transistor M6 further includes a gate coupled to the drain of the fourth transistor M4, and a drain coupled to the second voltage VSS.
The second clock inversion circuit 130 and the first clock inversion circuit 120 have similar structures. The second clock inversion circuit 130 includes a seventh transistor M7, an eighth transistor M8, a ninth transistor M9, and a tenth transistor M10. The seventh transistor M7 includes a gate for receiving the shift register signal VO from the inverter 12, a source coupled to the first voltage VDD, and a drain coupled to a source of the eighth transistor M8. The eighth transistor M8 further includes a gate and a drain coupled to the second voltage VSS. The ninth transistor M9 includes a source coupled to the source of the eighth transistor M8, a gate coupled to a gate of the tenth transistor M10, and a drain coupled to the gate of the fifth transistor M5. The gates of the ninth and tenth transistors M9 and M10 cooperatively serve as a second control terminal for receiving an inverse clock signal TS. The tenth transistor M10 further includes a source coupled to the gate of the seventh transistor M7 and the shift register signal VO of the inverter 120, and a drain coupled to the gate of the sixth transistor M6 via the second output VO2.
Referring to FIG. 6, this is a sequence waveform diagram of pulse signals of the shift register unit 100. During period t1, the third and fourth transistors M3 and M4 are switched off and the ninth and tenth transistors M9 and M10 are switched on because the start signal VS jumps to a low voltage and the clock signal TS jumps to a high voltage. Thus, the inverter 120 and the second clock inversion circuit 130 perform a latch operation. The sixth transistor M6 is switched off such that the shift register signal VO of the inverter 120 keeps an original state of the previous stage.
During period t2, the third and fourth transistors M3 and M4 are switched on and the ninth and tenth transistors M9 and M10 are switched off because the clock signal TS jumps to a low voltage and the inverse clock signal TS jumps to a high voltage. Thus, there is no latch operation. The start signal VS is applied to the inverter 120, and the inverter 120 and the second clock inversion circuit 130 keep the same state. Further, the first transistor M1 is switched on because the start signal VS jumps to a low voltage, such that the fifth transistor M5 is switched off and the sixth transistor M6 is switched on. Thus, the inverter 120 outputs the shift register signal VO having a low level through the activated sixth transistor M6.
During period t3, the third and fourth transistors M3 and M4 are switched off and the ninth and tenth transistors M9 and M10 are switched on because the clock signal TS jumps to a high voltage and the inverse clock signal TS jumps to a low voltage. Therefore the inverter 120 and the second clock inversion circuit 130 perform a latch operation. Thus, the shift register signal VO of the inverter 120 keeps the original state of period t2. The seventh transistor M7 is switched on by the shift register signal VO from the inverter 120, such that the transistor M5 is still off. In addition, the sixth transistor M6 maintains an on-state because the shift register signal VO is low level. Thus, the inverter 120 maintains output of the low level shift register signal VO through the activated sixth transistor M6.
During period t4, the third and fourth transistors M3 and M4 are switched on and the ninth and tenth transistors M9 and M10 are switched off because the clock signal TS jumps to a low voltage and the inverse clock signal TS jumps to a high voltage. Thus, there is no latch operation. The start signal VS is applied to the inverter 120. The inverter 120 and the second clock inversion circuit 130 keep the same state. The sixth and first transistors M6 and M1 are switched off and the fifth transistor M5 is switched on because the start signal VS is high level. Thus, the inverter 120 stops output of the low-level shift register signal VO.
The shift register unit 100 outputs a low level shift register signal during period t2, and at the same time, the next-stage shift register unit (not shown) also outputs a low level shift register signal. Thus, the adjacent shift register units may cause a conflict of signal outputting due to the overlapping of the adjacent shift register signals. As a result, the shift register is liable to be unstable. Accordingly, an LCD device using the shift register may have impaired display quality because adjacent scanning lines may be scanned simultaneously by the overlapping shift register signals instead of being scanned sequentially.
What is needed, therefore, is a shift register which can overcome the above-described deficiencies. What is also needed is an LCD including the shift register.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Hollow toroidal or oval pneumatic tires of the type disclosed in U.S. Pat. No. 3,606,921, issued Sept. 21, 1971 to C. E. Grawey and assigned to the assignee of the present invention represent a considerable advancement in the art. However, these tires have a substantially nonexpandable inner peripheral mounting surface because of their construction which usually includes a pair of transversely spaced restraining hoops near the radially inner base of the sidewalls. Accordingly, the rim mounting arrangement for such tires has been heretofore a rim structure with axially interlocking flange halves for grippingly holding the tire thereon. Each of the flange halves includes an outwardly flared or conical peripheral surface, so that as they are axially moved together they entrap the tire within the peripheral concavity formed by the opposing flared surfaces. The difficulty with this is that there is an initial gap between the flange halves in which the tire can be pinched, and further the tire has a tendency to axially slip a disproportionate amount on each flared surface so that during installation of the flanges the tire tends to buckle or become offcentered. As a result, the fastening devices which are utilized to secure the flange halves together must be sequentially limitedly tightened with considerable care to minimize these difficulties. Another problem is that the rim structures must be heavy and rugged in construction in order to withstand the relatively high assembly loads at an increase in cost and at a reduction in serviceability thereof.
Further exemplifying the state of the art are U.S. Pat. Nos. 991,045 issued May 22, 1911 to J. H. Andrews et al; U.S. Pat. No. 1,160,222 issued Nov. 16, 1915 to J. H. Wagenhorst; U.S. Pat. No. 1,582,575 issued Apr. 27, 1926 to J. G. Casteran; and U.S. Pat. No. 3,291,171 issued Dec. 13, 1966 to W. E. F. Lehmann. However, as far as is known none of these references have tire rim mounting arrangements which exhibit the degree of expandable tire gripping fit required along with a simple, lightweight, and economical structure. In addition, the methods of installing the rim mounting arrangements within the tires are relatively complex.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The production of oil and natural gas from an underground well (subterranean formation) can be stimulated by a technique called hydraulic fracturing, in which a viscous fluid composition (fracturing fluid) containing a suspended proppant (e.g., sand, bauxite) is introduced into an oil or gas well via a conduit, such as tubing or casing, at a flow rate and a pressure which create, reopen and/or extend a fracture into the oil- or gas-containing formation. The proppant is carried into the fracture by the fluid composition and prevents closure of the formation after pressure is released. Leak-off of the fluid composition into the formation is limited by the fluid viscosity of the composition. Fluid viscosity also permits suspension of the proppant in the composition during the fracturing operation. Cross-linking agents, such as borates, titanates or zirconates, are usually incorporated into the fluid composition to control viscosity.
Typically, less than one third of available oil is extracted from a well after it has been fractured before production rates decrease to a point at which recovery becomes uneconomical. Enhanced recovery of oil from such subterranean formations frequently involves attempting to displace the remaining crude oil with a driving fluid, e.g., gas, water, brine, steam, polymer solution, foam, or micellar solution. Ideally, such techniques (commonly called flooding techniques) provide a bank of oil of substantial depth being driven into a producing well; however, in practice this is frequently not the case. Oil-bearing strata are usually heterogeneous, some parts of them being more permeable than others. As a consequence, channeling frequently occurs, so that the driving fluid flows preferentially through permeable zones depleted of oil (so-called “thief zones”) rather than through those parts of the strata which contain sufficient oil to make oil-recovery operations profitable.
Difficulties in oil recovery due to thief zones may be corrected by injecting an aqueous solution of an organic polymer and a cross-linking agent into a subterranean formation under conditions where the polymer will be cross-linked to produce a gel, thus reducing permeability of the subterranean formation to the driving fluid (gas, water, etc.). Polysaccharide-or partially hydrolyzed polyacrylamide-based fluids cross-linked with certain aluminum, titanium, zirconium, and boron based compounds are used in these enhanced oil recovery applications. Cross-linked fluids or gels, whether for fracturing a subterranean formation or for reducing permeability of zones in subterranean formation, are now being used in hotter and deeper wells under a variety of temperature and pH conditions. In these operations the rate of cross-link is critical to the successful generation of viscosity. Frequently the rates of cross-linking with known cross-linking compositions are unacceptable, and new, highly specific compositions are required. Particularly, the need exists for cross-linkers which generate a high, thermally stable viscosity in a high pH environment.
Oil field service companies are currently using zirconium based cross-linkers to generate viscosity in polysaccharide-based fluids useful in hydraulic fracturing, completion and enhanced oil recovery applications. Commercially available, zirconium cross-linkers containing triethanolamine as a chelating ligand cross-link in the desired range and generate and maintain significant viscosity at 250° F. (121° C.), but at higher temperatures greater than or equal to 275° F., 135° C.) cross-link too fast. Replacement of triethanolamine with a hydroxyalkylated ethylenediamine chelating ligand such as in U.S. Pat. No. 4,798,902 gives a complex which cross-links too slowly at 250-275° F. (121-135° C.). The rate of cross-linking is critical to the successful generation of viscosity sufficient to conduct a fracturing operation.
Compositions are known in which aqueous zirconium compounds, triethanolamine and an α-hydroxycarboxylic acid are combined. Various processes have been used in combining these components to produce the compositions, such as those disclosed in U.S. Pat. Nos. 4,460,751; 5,182,408; and 5,798,320.
Some zirconium-based compositions of alkanolamine salts of α-hydroxycarboxylic acid may be used as cross-linkers in mid-high temperature fracturing fluid applications. While it is has been found that such triethanolamine zirconate complexes with α-hydroxycarboxylic acids have slower rates of cross-linking than similar complexes without α-hydroxycarboxylic acids, viscosity generation and retention are sacrificed, especially at temperatures greater than or equal to 275° F. (135° C.).
There is a need for zirconium-based cross-linking compositions which have a desirable 3-8 minute delay in rate of cross-linking without sacrificing the viscosity development capability of the zirconium composition at both lower mid temperature (up to 250° F., 121° C.) and at higher temperature (greater than 250° F., 121° C., especially greater than or equal to 275° F., 135° C.). That is, which will allow the cross-linking compositions to be used at a temperature greater than or equal to 250° F. (121° C.) and maintain adequate viscosity to ensure successful completion of the fracturing operation. The present invention meets these needs.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to data communication. More particularly, the present invention relates to a novel and improved method and apparatus for forward link rate scheduling of high speed data transmission in a communication system having a variable data transmission rate.
2. Description of the Related Art
A modern day communication system is required to support a variety of applications. One such communication system is a code division multiple access (CDMA) system which conforms to the “TIA/EIA/IS-95A Mobile Station-Base Station Compatibility Standard for Dual-Mode Wideband Spread Spectrum Cellular System”, hereinafter referred to as the IS-95A standard. The CDMA system allows for voice and data communications between users over a terrestrial link. The use of CDMA techniques in a multiple access communication system is disclosed in U.S. Pat. No. 4,901,307, entitled “SPREAD SPECTRUM MULTIPLE ACCESS COMMUNICATION SYSTEM USING SATELLITE OR TERRESTRIAL REPEATERS”, and U.S. Pat. No. 5,103,459, entitled “SYSTEM AND METHOD FOR GENERATING WAVEFORMS IN A CDMA CELLULAR TELEPHONE SYSTEM”, both assigned to the assignee of the present invention and incorporated by reference herein.
The IS-95A standard is designed to optimize voice communication and many important system design parameters are selected to achieve that goal. For example, since time delay between speakers cannot be tolerated, processing delays are sought to be minimized. Each user is allocated a traffic channel capable of carrying speech data for the duration of the call. Upon termination of the call, the traffic channel becomes available for another user.
In accordance with the IS-95A standard, each traffic channel is designed to support a symbol rate of 19.2 Ksps. Using a rate ½ convolutional encoder, the data rate of each traffic channel approaches 9.6 Kbps. Although not specified by the IS-95A standard, higher data rates can by supported by the use of other code rates. For example, a data rate of 14.4 Kbps is achieved by using a rate ½ convolutional encoder and deleting two out of every eight symbols, to obtain a punctured rate ¾ convolutional encoder.
The CDMA system must work within the pre-existing frequency allocation in the cellular band. By design, a CDMA system which conforms to the IS-95A standard is allotted a 1.2288 MHz bandwidth to fully utilize the cellular band. The forward link refers to transmission from a cell to the remote stations. On the forward link, the 1.2288 MHz bandwidth is divided into 64 code channels, with each code channel having a capacity of 19.2 Ksps. Most of the code channels are defined as traffic channels which are allocated, upon demand, to users for voice communication. Some code channels are defined as paging channels used for paging and messaging between the cell and the remote stations. Several code channels, such as the pilot and sync channels, are reserved for system overhead.
In the CDMA system, users communicate with one another through remote stations which, in turn, communicate with each other through one or more base stations. In this specification, base station refers to the hardware with which the remote stations communicate. Cell refers to the hardware or the geographic coverage area, depending on the context in which the term is used.
In the CDMA system, communications between users are conducted through one or more cells which are serviced by base stations. A first user on one remote station communicates to a second user on a second remote station, or a standard telephone, by transmitting voice data on the reverse link to a cell. The cell receives the voice data and can route the data to another cell or a public switched telephone network (PSTN). If the second user is on a remote station, the data is transmitted on the forward link of the same cell, or a second cell, to the second remote station. Otherwise, the data is routed through the PSTN to the second user on the standard phone system. In IS-95A systems, the forward link and the reverse link are allocated separate frequency and are independent of one another.
The remote station communicates with at least one cell during a communication. CDMA remote station are capable of communicating with multiple cells simultaneously during soft handoff. Soft handoff is the process of establishing a link with a new cell before breaking the link with the previous cell. Soft handoff minimizes the probability of dropped calls. The method and system for providing a communication with a remote station through more than one cell during the soft handoff process are disclosed in U.S. Pat. No. 5,267,261, entitled “MOBILE ASSISTED SOFT HANDOFF IN A CDMA CELLULAR TELEPHONE SYSTEM,” assigned to the assignee of the present invention and incorporated by reference herein. Soft handoff impacts various aspects of the CDMA system design because considerations should be given to the status and capacity of each of the multiple cells involved in the soft handoff when a new allocation of resource is made.
The CDMA system is a spread spectrum communication system. The benefits of spread spectrum communication are well known in the art and can be appreciated by reference to the above cited references. Each code channel in the CDMA system can transmit up to 19.2 Ksps. The 19.2 Ksps is then spread over the entire 1.2288 MHz system bandwidth. The IS-95A CDMA system increases capacity by transmitting fewer bits, thereby using less power, when the user is not speaking. Since the forward link capacity between the cell and the remote station is limited by the maximum transmit power available for the cell, decreasing the transmit power during idle periods increases the forward link capacity.
The user on each remote station transmits at a different bit rate depending on the level of speech activity in the conversation of that user. A variable rate speech vocoder provides speech data at full rate when the user is actively speaking and at low rate during period of silence, e.g. pauses. The variable rate vocoder is described in detail in U.S. Pat. No. 5,414,796, entitled “VARIABLE RATE VOCODER,” assigned to the assignee of the present invention and incorporated by reference herein.
The forward link capacity for voice communication between the cell and the remote stations, as measured by the number of users supportable by the CDMA system, can be determined by the bit rate of the user on each remote station. This is because other parameters determinative of the forward link capacity are fixed by the system design or given. For example, the maximum transmit power available for each cell is limited by FCC regulations and also by the acceptable levels of adjacent cell interference. The transmit power required for a given symbol rate depends on the energy-per-bit-to-noise ratio (Eb/No) required by the remote station, the path loss (e.g. location of the remote station within the cell) and the noise level, all of which cannot be controlled. The Eb/No required to maintain the desired level of performance is dependent on the channel condition, e.g. fading. Finally, the CDMA system bandwidth of 1.2288 MHz is selected by design.
On the forward link, the required transmit power is also dependent on the orthogonality of the code channels. Walsh code spreading is used to achieve orthogonality of the forward link code channels. The orthogonality minimizes the interference between the code channels. This orthogonality is not preserved in a multipath environment and, as the result, the level of interference increase. The required transmit power is then increased to maintain the same operating Eb/No.
The amount of speech activity at any given moment is non-deterministic. Also, there is typically no correlation in the level of speech activities among users. Therefore, the total power transmitted from a cell to all users in that cell varies over time and can be approximated as a Gaussian distribution. During the period of time when the level of speech activities is high and the required transmit power exceeds the maximum transmit power available to the cell, each voice data bit is transmitted with less power than would be optimal. Since the path loss is fixed, the Eb/No drops. The lower Eb/No increases the probability of frame errors in the voice data received by the users. This event is known as an outage.
The number of users able to have access to the communication system is limited so that a predetermined frame error rate (FER) is maintained. Limiting the forward link capacity to maintain the predetermined FER has the effect of forcing the cell to transmit at less than full capacity, on the average, thereby under-utilizing the forward link capacity of the cell. In the worse case, up to half of the forward link capacity is wasted to maintain a headroom of up to 3 dB. The headroom is the difference between the maximum transmit power available to the cell and the average transmit power of the cell. The headroom is only utilized during the period when the speech activities of the users are high.
Data communication within the CDMA system has different characteristics than voice communication. For example, data communication is typically characterized by long period of inactivity, or low activity, punctuated by high bursts of data traffic. An important system requirement for data communication is the transmission delay required to transfer the burst of data. Transmission delay does not have the same impact in data communication as it does for voice communication, but it is an important metric for measuring the quality of the data communication system.
A method for transmitting data traffic in code channel frames of fixed size, wherein the data source provides data at a variable rate, is described in detail in U.S. Pat. No. 5,504,773, entitled “METHOD AND APPARATUS FOR THE FORMATTING OF DATA FOR TRANSMISSION”, assigned to the assignee of the present invention and incorporated by reference herein. Data is partitioned into data frames and each data frame may be further partitioned into data portions. The data portions are then encoded into code channel frames which are 20 msec wide. At the 19.2 Ksps symbol rate, each code channel frame contains 384 symbols. A rate ½, or a rate ½ punctured to obtain a rate ¾, convolutional encoder is used to encode the data, depending on the application. Using a rate ½ encoder, the information rate is approximately 9.6 Kbps. At the 9.6 Kbps data rate, there are 172 data bits, 12 cyclic redundancy check (CRC) bits and 8 code tail bits per code channel frame.
High speed data transmission on the forward link can be achieved by concurrently transmitting data traffic over multiple code channels. The use of multiple code channels for data transmission is disclosed in U.S. patent application Ser. No. 08/656,649, entitled “METHOD AND APPARATUS FOR PROVIDING RATE SCHEDULED DATA IN A SPREAD SPECTRUM COMMUNICATION SYSTEM”, filed May 31, 1996, assigned to the assignee of the present invention and incorporated by reference herein.
The demand for the forward link continuously changes over time, in part due to variations in the level of voice activities. The inefficient use of the forward link can be improved by transmitting data traffic during the period of low voice activity. To avoid degradation in the quality of the voice communication, the data transmission should be dynamically adjusted to match the available forward link capacity of the cell.
In dealing with large sporadic bursts of data traffic, a system should be designed with the capability to transmit at high data rates and the ability to allocate the forward link resource to the users whenever requested, based on the availability of the resource. In a CDMA system, the design should address other existing system considerations. First, since voice communication cannot tolerate extensive delay, priority should be given to transmission of voice data over transmission of any data traffic. Second, since the amount of voice activity at any given moment is unpredictable, the forward link should be continuously monitored and the data transmission should be dynamically adjusted so that the forward link capacity is not exceeded. Third, since the user may be in soft handoff between multiple cells, the data transmission rate should be assigned based on the forward link capacity of each of the cells participating in the soft handoff. These and other considerations are addressed by the present invention.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Mobile devices are used in various locations around the world to capture, send, and receive information. For example, mobile phone uses may take pictures, take video, or request information over a cellular or computer network. This information may be shared with other users or stored on a network.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Personal digital assistants such as mobile phones, smartphones, and tablet computers or electronic devices such as computers include display devices including display panels such as liquid crystal panels. Each of such display devices includes a display panel and a drive. The display panel includes a display area for displaying images. The driver includes a Large-Scale Integrated circuit (LSI) configured to process input signals from a signal source and send generated output signals to the display area for driving the display panel. In general, it is preferable to use a chip on glass (COG) technology to directly mount a driver on a display panel in a non-display area outside a display area in display devices classified as small and medium sized display devices. An example of a display device of this kind is a display device disclosed in Patent Document 1.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to the fields of publishing, document editing and manipulation, and displaying documents and images. More particularly, the present invention relates to paginating, extracting, synchronizing, and displaying, a document in electronic form.
2. Art Background
As the development of multimedia computer display systems continues to advance, more computing power and features are available to computer users. For example, information which has historically been limited to published paper documents is now being made available through on-line computing services from publishers and information vendors. As an increasing market share of the data and computing capacity is provided through low cost high performance personal computers, some of the on-line information is also being made available in compact disks (CD) and magnetic media formats. Compact disk and magnetic media technology offer cost effective mass storage of documents, images and other data, in a format readily accessible for use with personal computers in a home or office environment. The combination of personal computers, compact disk technology and multimedia interactive graphic user interfaces, permits the access and display of textual and graphic information by personal computer (PC) users in a manner not previously known in the industry. The type of information potentially available to a PC user includes professional and technical publications, newspapers, magazines, and other scientific and literary data and images.
However, much of the information which is published through, for example, government sources, newspapers and magazines is not in machine readable form, but rather is printed on paper. Because of the amount of work and effort required to convert the printed information into a machine readable form, only a small portion of the total published information is currently available for use by PC users using magnetic disks, CDs and the like. In addition, the information which is in machine readable form is typically available either as an image of the original document or as a stream of text data. An image of a document has the advantage of presenting the information in its original format as published, including non-text material, such as drawings, equations, symbols, diagrams, etc. The viewer is familiar with the format, and the information is easily recognized and understood. However, since a document image is often stored as a bitmap, the content of the document cannot be easily searched or manipulated. Alternatively, a text data stream format has the advantage of presenting the information in a manipulable and searchable format. Unfortunately, in many cases, the format of presentation is not the format in which the information was originally published in print. Thus, the users are often unfamiliar with the format, inhibiting easy navigation of the document making information difficult to find and use.
One example of the problem of reproducing originally published documents stored in machine readable form, is the storage and display of United States patent documents by the United States Government. The United States Patent Office (herein referred to as the "PTO") provides magnetic tapes of issued U.S. patents and other documents, in the form of a scanned in image, and as a separate stream of text data. The magnetic tape storing the text data does not include graphical illustrations such as drawings, charts, textual tables, or much in the way of formatting data. Thus, the reproduction of a United States patent from PTO Text Files stored on magnetic tape does not result in the display of a U.S. patent as originally published by the U.S. Government. An example of a well known system for displaying text files provided by the PTO is that of the LexPat.RTM. system provided by Mead Data offered in conjunction with the Lexis.RTM. display system. Using the LexPat.RTM. system, the display of a U.S. patent on a terminal, such as a PC, results in a display of text only, and does not include drawings, charts, graphs, or original formatting information. The text of a selected patent appears in ASCII format, but does not appear as the original patent issued by the PTO, and may not be referenced by the original column and line numbers from the published patent. Other systems display text files of periodicals such as the Wall Street Journal or legal documents such as contracts. However, the text files do not appear as the original documents.
The U.S. Patent Office also provides magnetic tapes with image files comprising a scanned in image of the original U.S. patent issued by the PTO and published by the U.S. Government. The image files provided on magnetic tape by the PTO simply represent a bitmap image of the original published patent. As a scanned in image, the entire patent is provided including drawings, charts, graphs, text and the original format, since it represents a simple bitmap of the scanned original document. However, a scanned document may not be easily searched, edited, navigated or otherwise manipulated as can a text file.
As will be described, the present invention provides a method and apparatus for extracting, synchronizing, displaying, navigating and manipulating text and image documents simultaneously in electronic form. The present invention is described with particular reference for use with U.S. patent documents, and includes the process of extracting patent text and image data from magnetic tapes provided by the PTO, synchronizing the text and image data for recovering the original format (i.e., columns and lines) of the original published patent, and displaying the formatted text along with images using a unique graphical user interface (GUI) workbench. Although the present invention is described with reference to patent documents, it will be appreciated that the invention has application to a variety of different types of documents and applications.
The present invention's graphical user interface permits a user to selectively view ASCII text documents as well as bitmapped scanned images simultaneously on a display. When used in conjunction with U.S. patent documents, the graphic user interface of the present invention allows a user, such as a patent attorney, to display and manipulate both textual as well as graphic portions of patents. The text of a patent may be viewed on the display as it was originally published by the PTO, including column and line numbers. Simultaneously, the user may view the figures of a patent in the form of an image comprising a bitmap. Various functions are provided by the present invention for viewing, manipulating and displaying the patent documents. In order to assist the reader in understanding of graphic user interface (GUI) technology, it is suggested that certain references be considered for background. Many user interfaces utilize metaphors in the design of the interface as a way of maximizing human familiarity, and conveying information between the user and the computer. As for the use of familiar metaphors, such as desktops, notebooks, spread sheets, and the like, the interface takes advantage of existing human mental structures to permit a user to draw upon the metaphor analogy to understand the requirements of the particular computer system. (See for example, Patrick Chan "Learning Considerations in User Interface Design: The Room Model", Report CS-84-16, University of Waterloo, Computer Science Department, Ontario, Canada, July, 1984 and the references cited therein.) In addition, the reader is referred to the following references which describe various aspects, methods and apparatus associated with prior art graphic user interface design: U.S. Pat. No. Re.32,632; U.S. Pat. No. 4,931,783; U.S. Pat. No. 5,072,412; and U.S. Pat. No. 5,148,154, and the references cited therein.
As will be described more fully below, the present invention's graphic user interface is based on a desktop "windows" metaphor, and provides the user with the ability to simultaneously display text and image documents in both a synchronized and unsynchronized fashion, as will be more fully described herein.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to a control device, more particularly to a control device for suppression of residual vibration of a piezoelectric transducer.
2. Description of the Related Art
A parking sensor is usually implemented by using aluminum shell stuck with a piezoelectric transducer. When a driving signal is transmitted to the parking sensor, the piezoelectric transducer will transform electrical energy into mechanical force due to piezoelectricity so as to cause the aluminum shell to vibrate for generating an ultrasonic wave signal. After the emission of the ultrasonic wave signal, the parking sensor will transfer into the sensing mode and keep sensing an echo signal which was generated by reflection of the ultrasonic wave signal when bumping into an obstacle. By calculation of the time difference between the moment when the ultrasonic wave emit and the moment when the parking sensor receive the echo signal, one could estimate the distance between the sensor and the obstacle. If a vehicle equipped with the parking sensor is about to bump into an obstacle, the parking sensor could sense the distance between the vehicle and the obstacle and start to notify the vehicle driver when the distance difference reaches a set value. The warning sound of the notification could be in a beeping rhythm that corresponds to the distance between the vehicle and the obstacle in order to let the driver know that he is getting closer to the obstacle. Nevertheless, after emission of the ultrasonic wave signal, the piezoelectric transducer and the aluminum shell could not stop vibrating right away due to their elasticity and the residual vibration will damp away as the energy being drained to overcome frictional or other resistive forces. A recovery time which the parking sensor needs to damp the residual vibration away forms a blind range in sensing obstacles. Obstacles in the blind range could not be sensed since the echo signal reflected by it reaches the parking sensor while it is still in the residual vibration and the parking sensor could not distinguish the echo signal from the residual vibration. Therefore, the residual mechanical vibration of the piezoelectric transducer must be suppressed to reduce a minimum distance that could be estimated by the parking sensor.
Referring to FIG. 1 and FIG. 2, a control device for suppression of residual vibration of a piezoelectric transducer 1 includes a driving circuit 2, a residual control circuit 3, and a switch circuit 4. The control device could be operated either in a working mode or in a non-working mode. Under the working mode, the switch circuit 4 couples the driving circuit 2 electrically to the piezoelectric transducer 1, and the driving circuit 2 outputs a sinusoidal electric current as a driving signal for driving the piezoelectric transducer 1 to vibrate. Under the non-working mode, the switch circuit 4 couples the residual control circuit 3 electrically to the piezoelectric transducer 1, and the residual control circuit 3 suppresses residual vibration of the piezoelectric transducer 1. During residual vibration of the piezoelectric transducer 1, the piezoelectric transducer 1 outputs an electric current due to piezoelectricity. The electric current remains sinusoidal, yet has relatively low amplitude.
A conventional residual control circuit 3′ includes a direct current power source 31, and a switch unit 32. The direct current power source 31 supplies a direct current reference voltage. The switch unit 32 includes four switches 321 to 324. Under the non-working mode, when the electric current of the piezoelectric transducer 1 is positive (i.e., flow of the electric current from a first end of the piezoelectric transducer 1 toward a second end thereof, wherein the first end is connected to each of the switches 321, 322, and the second end is connected to each of the switches 323, 324), the switch unit 32 operates such that the switches 321, 323 conduct, and the direct current power source 31 provides a voltage equivalent to a positive direct current reference voltage for the piezoelectric transducer 1. When the electric current of the piezoelectric transducer 1 is negative (i.e., flow of the electric current from the second end of the piezoelectric transducer 1 toward the first end thereof), the switch unit 32 operates such that the switches 322, 324 conduct, and the direct current power source 31 provides a voltage equivalent to a negative direct current reference voltage for the piezoelectric transducer 1. In this way, the electric current outputted from the piezoelectric transducer 1 and the voltage applied thereto are in-phase, such that energy dissipation of the piezoelectric transducer 1 during each residual cycle is maximized for suppressing residual vibration of the piezoelectric transducer 1.
Even though the conventional residual control circuit 3′ may indeed suppress residual vibration of the piezoelectric transducer 1 in an initial stage of the non-working mode, when residual vibration thereof has been reduced to a very small level, energy of the direct current power source 31 may disturb convergence of vibration of the piezoelectric transducer 1 through the switch unit 32, and may even cause the piezoelectric transducer 1 to vibrate once again.
Furthermore, in “Velocity-Controlled Piezoelectric Switching Energy Harvesting Device” by Y. P. Liu et al., International Conference on Renewable Energies and Power Quality (ICREPQ), April, 2009, an energy harvesting device which harvests energy from a piezoelectric transducer is disclosed. The energy harvesting device uses super (ultra) capacitors to store harvested energy.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to electron beam apparatus, including scanning electron microscopes and the like, and method of operating such apparatus.
2. Description of the Background Art
There is an increasing need for high-resolution scanning electron microscopes (SEMs) in all areas of development and manufacture of micro-electronic and opto-electronic components. High-resolution scanning electron microscopes are useful so as to visually evaluate sub-micrometer structures. High-resolution SEMs may be used to identify deviations from standard patterns and to acquire and evaluate topographical data such as heights, widths or angles of inclination.
Unfortunately, conventional, non-immersion, scanning electron microscopes do not have the required resolution of a few nanometers unless very high landing energies above about 10 kilo-electronVolts are used which may cause resist structures and, integrated circuits to be damaged and non-conductive or high resistant specimens to be disadvantageously charged.
It is highly desirable to improve electron beam apparatus, including scanning electron microscopes and the like, and methods of operating such apparatus.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
This invention is generally in the area of drug delivery systems, especially in the area of gastrointestinal, vaginal and respiratory drug delivery.
Drug delivery takes a variety of forms, depending on the agent to be delivered and the administration route. A preferred mode of administration is non-invasive; i.e., administration via nasal or oral passages. Some compounds are not suited for such administration, however, since they are degraded by conditions in the gastrointestinal tract or do not penetrate well into the blood stream.
Controlled release systems for drug delivery are often designed to administer drugs in specific areas of the body. In the gastrointestinal tract it is critical that the drug not be entrained beyond the desired site of action and eliminated before it has had a chance to exert a topical effect or to pass into the bloodstream. If a drug delivery system can be made to adhere to the lining of the appropriate viscus, its contents will be delivered to the targeted tissue as a function of proximity and duration of the contact.
There are two major aspects to the development of an adhesive bond between a polymer and the gastrointestinal tissue: (i) the surface characteristics of the bioadhesive material, and (ii) the nature of the biological material with which the polymer comes in contact. The intestinal mucosa is formed of a continuous sheet of epithelial cells of absorptive and mucin-secreting cells. Overlying the mucosa is a discontinuous protective coating, the mucus, which is made of more than 95% water, as well as electrolytes, proteins, lipids and glycoproteins--the latter being responsible for the gel-like characteristics of the mucus. These glycoproteins consist of a protein core with covalently attached carbohydrate chains terminating in either sialic acid or L-fucose groups. The carbohydrate structure of the intestinal mucous glycoproteins is similar to that of the glycoproteins which are part of the epithelial cell membrane. The mucous glycoproteins act as "dummy receptors" for carbohydrate binding ligands which have evolved in nature to allow microorganisms and parasites to establish themselves on the gut wall. One function of the mucus is to intercept these ligands and associated ineffective agents and thereby protect the mucosa.
An orally ingested product can adhere to either the epithelial surface or the mucus. For the delivery of bioactive substances, it would be advantageous to have a polymeric device adhere to the epithelium rather than solely to the mucous layer, although mucoadhesion may also substantially improve bioavailability. For some types of imaging purposes, adhesion to both the epithelium and mucus is desirable whereas in pathological states, such as in the case of gastric ulcers or ulcerative colitis, adhesion to cells below the mucous layer may occur.
Bioadhesion in the gastrointestinal tract proceeds in two stages: (1) viscoelastic deformation at the point of contact of the synthetic material into the mucus substrate, and (2) formation of bonds between the adhesive synthetic material and the mucus or the epithelial cells.
Several microsphere formulations have been proposed as a means for oral drug delivery. These formulations generally serve to protect the encapsulated compound and to deliver the compound into the blood stream. Enteric coated formulations have been widely used for many years to protect drugs administered orally, as well as to delay release. Other formulations designed to deliver compounds into the blood stream, as well as to protect the encapsulated drug, are formed of a hydrophobic protein, such as zein, as described in PCT/US90/06430 and PCT/US90/06433; "proteinoids", as described in U.S. Pat. No. 4,976,968 to Steiner; or synthetic polymers, as described in European Patent application 0 333 523 by The UAB Research Foundation and Southern Research Institute. EPA 0 333 523 describes microparticles of less than ten microns in diameter that contain antigens, for use in oral administration of vaccines. The microparticles are formed of polymers such as poly(lactide-co-glycolide), poly(glycolide), polyorthoesters, poly(esteramides), polyhydroxybutyric acid and polyanhydrides, and are absorbed through the Peyer's Patches in the intestine, principally as a function of size.
It would be advantageous if there was a method or means for controlling or increasing the absorption of these particles through the mucosal lining, or for delaying still further transit of the particles through the nasal or gastrointestinal passages.
Duchene, et al., Drug Dev. Ind. Pharm. 14(2&3), 283-318 (1988), reviews the pharmaceutical and medical aspects of bioadhesive systems for drug delivery. "Bioadhesion" is defined as the ability of a material to adhere to a biological tissue for an extended period of time. Bioadhesion is clearly one solution to the problem of inadequate residence time resulting from the stomach emptying and intestinal peristalsis, and from displacement by ciliary movement. For sufficient bioadhesion to occur, an intimate contact must exist between the bioadhesive and the receptor tissue, the bioadhesive must penetrate into the crevice of the tissue surface and/or mucus, and mechanical, electrostatic, or chemical bonds must form. Bioadhesive properties of the polymers is affected by both the nature of the polymer and by the nature of the surrounding media.
Duchene, et al., tested polymers for bioadhesion by measuring the surface tension between a plate containing a mucus sample and a polymer coated glass plate. They review other systems using intestinal membrane rather than a mucosal solution, and in vivo studies using rats and radiolabeled polymeric material in a gelatin capsule. A number of polymers were characterized as to their bioadhesive properties but primarily in terms of "excellent" or "poor". Polycarbophils and acrylic acid polymers were noted as having the best adhesive properties, although the highest adhesive forces were still less than 11 mN/cm.sup.2.
Others have explored the use of bioadhesive polymers. Smart, et al., J. Pharm. Pharmacol. 36:295-299 (1984), reported on a method to test adhesion to mucosa using a polymer coated glass plate contacting a dish of mucosa. A variety of polymeric materials were tested, including sodium alginate, sodium carboxymethylcellulose, gelatin, pectin, and polyvinylpyrrolidone. Gurney, et al., Biomaterials 5, 336-340 (1984), concluded that adhesion may be effected by physical or mechanical bonds; secondary chemical bonds; and/or primary, ionic or covalent bonds. Park, et al., Alternative Approaches to Oral Controlled Drug Delivery: Bioadhesives and In-Situ Systems 163-183 J. M. Anderson and S. W. Kim, ed., Recent Advances in Drug Delivery (Plenum Press NY 1984), reported on the use of fluorescent probes in cells to determine adhesiveness of polymers to mucin/epithelial surfaces. Their results indicated that anionic polymers with high charge density appear to be preferred as adhesive polymers.
None of these studies involved the study of tensile measurement between microspheres and intestinal tissue. Microspheres will be affected by other factors, such as the mucosal flow, peristaltic motion, high surface area to volume ratio, Mikos, et al., in J. Colloid Interface Sci. 143, 2:366-373 (May 1991) and Lehr, et al., J. Controlled Rel. Soc. 13:51-62 (1990), both disclose the bioadhesive properties of polymers used for drug delivery: polyanhydrides and polyacrylic acid, respectively. Mikos, et al., report that the bioadhesive forces are a function of surface area, and are significant only for particles in excess of 900 microns in diameter (having a maximum adhesive force of 120 .mu. N for a sphere with a diameter of approximately 1200.mu., equivalent to 10.9 mN/cm.sup.2), when measured in vitro. However, they also note that this may not be an adequate adhesive force in vivo, since the larger particle size is also subjected to greater flow conditions along the mucosa which may serve to displace these larger particles. In addition, Mikos, et al., found very small forces for particles smaller than 750.mu.. Lehr, et al., screened two commercially available microparticles of a diameter in excess of 500 microns formed of copolymers of acrylic acid, using an in vitro system, and determined that one copolymer "Polycarbophil" increased adhesion over a control but that the other polymer did not. Polymeric coatings were also applied to polyhydroxyethylmethacrylic acid and tested in an in vivo model. As shown in Table 1 of Mikos, et al., the maximum adhesive force was approximately 9 mN/cm.sup.2 for Polycarbophil.
Most prior art techniques for measuring in vitro bioadhesion are based on tensile experiments. These techniques were mainly designed for large tablets or polymer coated onto glass plates. Only a few in vitro techniques for direct measurement of adhesion forces between individual microcapsules and intestinal tissue are known. Some publications report on a flow channel method. However, the only reported results are static measurements where the mucoadhesive force exerted on each particle was determined by placing small particles over intestinal mucosa and measuring the immersed surface area and the directional contact angles using video microscopy, as described by Mikos, et al.
It is therefore an object of the present invention to provide bioadhesive polymeric microspheres that are useful for drug delivery via the mucosal membranes.
It is a further object of the present invention to provide polymeric microspheres which can be used for imaging studies.
It is another object of the present invention to provide a method for determining bioadhesiveness of polymeric microspheres.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to a vertical cavity surface emitting laser element, a vertical cavity surface emitting laser array element, a vertical cavity surface emitting laser device, a light source device, and an optical module.
2. Description of the Related Art
Vertical cavity surface emitting lasers (VCSEL: vertical cavity surface emitting laser is hereinafter referred to as “surface emitting laser element”) are used as light sources for various optical communications including optical interconnections, or other various devices for applications (for example, see Japanese Patent Application Laid-open No. 2005-252111). Because surface emitting laser elements emit laser beams vertically to substrates, a plurality of elements are able to be two-dimensionally arrayed on the same substrate more easily than conventional edge emitting laser elements. Moreover, they have many advantages because the volumes of active layers are very small, like laser emissions with extremely low threshold currents and low electric power consumptions being possible. Such a surface emitting laser element uses a distributed Bragg reflector (DBR) mirror, which is formed of a periodic structure of low-refractive-index layers and high-refractive-index layers and which is a mirror constituting a cavity.
When a DBR mirror is stacked on a substrate, there is a problem that dislocation occurs due to lattice mismatch between the substrate and the DBR mirror, and the surface emitting laser element becomes less reliable or defective. That is, because the layer thickness of the DBR mirror is thick, strain accumulates in the DBR mirror due to the lattice mismatch. As the DBR mirror becomes thicker, crystal defects aggregate and form a dislocation network. This is generally observed as linear dislocation (cross-hatches), and is a cause of a defect if introduced into an active layer of the surface emitting laser element. Particularly, cross-hatches extremely decrease the manufacturing yield for an array element. This is because the cross-hatches pass straight through each active layer of the array element.
To reduce this dislocation, conventionally, a surface emitting laser element that employs a substrate added with indium (In) to reduce a warp of the substrate and decrease the occurrence of dislocation (see, Japanese Patent Application Laid-open No. 2005-252111); and a surface emitting laser element, in which a lattice constant of a multi-element mixed crystal such as AlGaAsP or AlGaInP, which is a semiconductor material constituting a DBR mirror, is made close to that of a GaAs substrate to maintain lattice match and reduce dislocation (see, Japanese Patent Application Laid-open No. 2002-100834, and Japanese Patent Application Laid-open No. H6-196821), have been proposed.
Thermal impedances of DBR mirrors in surface emitting laser elements are desirably made low. Making the thermal impedance of a DBR mirror low have advantageous like its reliability being improved because of suppression of a temperature rise in the active layer; a roll-over current value being increased, which is advantageous when performing high frequency modulation; and the stability of emission wavelength being improved because of decrease in temperature dependency of reflected wavelength characteristics and the like.
As a method of making the thermal impedance of a DBR mirror low, there is a method of forming a DBR mirror with a semiconductor material having a high composition of aluminum (Al), which has high thermal conductivity, like AlGaAs having an Al composition of 0.8 or higher.
However, AlGaAs with a high Al composition has a lattice strain of approximately 0.14% for example, with respect to GaAs, and thus there is a problem that when the Al composition is increased in a DBR mirror made of AlGaAs formed on a GaAs substrate, cross-hatches generated on the surface are increased.
Moreover, conventional techniques for reducing the dislocation have the following problems. That is, in a technique of adding In to a substrate, it is technically very difficult to add In uniformly. In a technique of forming a DBR mirror with a multi-element mixed crystal material, it is not possible to make the Al composition high because of the multiple elements. In other words, it has been difficult to simultaneously make the thermal impedances and dislocation in BR mirrors low.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The invention relates generally to apparatus for preparing on a continuous basis, mixtures of a plurality of constituent materials and, more specifically, to apparatus for continuous flow weighing of a dry flowable material for addition in a desired proportion to a mixture.
Mixtures or rations are typically made by mixing multiple ingredients by either the technique of batching by volume or weight or by the technique of continuous volumetric proportioning. Batching by volume or weight requires use of a batch mixer. Each ingredient is loaded into the mixer sequentially, the amount of each ingredient to be added is measured either by volume or, more accurately, by weight. After all of the ingredients have been loaded into the mixer, the mixer is operated until a homogeneous mixture of the ingredients is obtained.
The batching method provides for accurate measuring of ingredients and can be automated to load ingredients according to predefined recipes. Its disadvantages include the time required for sequential loading of ingredients, inaccuracy if ingredients are measured by volume, and operator error as is often the case with microingredients (i.e., ingredients added in very small proportional amounts).
The volumetric proportioning method does not require a mixer. Each ingredient flows simultaneously through separate augers into a common gathering auger. The flow rate of each ingredient is controlled by controlling the speed of the individual ingredient augers. Volumetric proportioning can be accomplished with a simple, compact system that does not require a mixer and which is potentially inexpensive to purchase and maintain. This method, however, has relatively low accuracy, being dependent on material flow characteristics and constancy of material density. Microingredients must typically be preblended into another ingredient to obtain the necessary minimum flow rates of the augers. Further, volumetric flow proportioning requires a separate metering auger for each ingredient.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Fluid pressure actuated grippers are widely employed and typically take the form of a pneumatic or hydraulic differential motor whose cylinder is fixedly mounted to a transfer device. At the forward or rod end of the cylinder housing, a gripper jaw mounting structure is fixedly mounted on the cylinder to pivotally support a pair of opposed gripper jaws which are coupled to the piston rod of the motor by a linkage so arranged that upon movement of the piston in one direction the jaws are pivoted to an open position and upon movement of the piston in the opposite direction the jaws are driven to a closed workpiece gripping position.
In typical operation, the gripper jaws will be closed upon a workpiece near the edge of the workpiece and the gripper will be advanced to position the gripped workpiece in operative relationship with a work station. The gripper will then be opened to release the workpiece and the transfer device will retract the gripper from the work station while the work operation is performed. At the conclusion of the work operation, the gripper will then advance back into the work station and the jaws will again close upon the workpiece and carry it away from the work station. Opening and closing the gripper jaws thus takes place when the gripper is in its closest proximity to tooling at the work station.
There are basically two types of linkage arrangements used in fluid pressure actuated grippers to connect the gripper jaws to the piston rods and effect movement of the gripper jaws. These are pivotable link arrangements and pivotal cam arrangements. An example of a pivotal link arrangement can be found in U.S. Pat. No. 5,152,568 to Blatt which discloses pivotal links 36 and 40 that cooperate with gripper jaws 12A and 12B as shown in FIG. 3.
U.S. Pat. No. 4,518,187 to Blatt et al. discloses a pivotal cam arrangement in which jaw plates 45 and 47 are pivoted by the cooperation of cam slots 61 provided in the jaw plates and a pivot pin 37 (and rollers 39) attached to the piston rod.
In a typical production line, there are numerous work stations with one or more fluid pressure actuated gripper devices positioned between adjacent work stations. During operation, all of the gripper devices are synchronized so that they simultaneously remove a workpiece from one work station and transfer the workpiece to the next work station. In such an operation, a problem can occur if any one of the gripper devices fails to properly grip a workpiece. For example, if a workpiece slips from its initial gripped position it can become sufficiently out of alignment to prevent its transfer to a succeeding gripper device. A more serious problem can occur if a workpiece is transferred in a misaligned manner and subsequently positioned at a work station in a misaligned fashion. Such an incident can damage the work station. Another problem which can occur is completely losing grip of a workpiece and dropping the workpiece. Losing grip of a workpiece can occur when there is a leak or failure of fluid pressure supplied to the piston rod actuator.
Fluid pressure actuated grippers are generally designed for use with particular workpieces to be transferred and with specific work stations. For example, some workpieces and/or work stations may require wider or narrower gripper jaws, different types of gripper jaws, gripper jaws that open at different angles, different clearance requirements, etc. Because of the wide variety of design or performance options required of grippers, manufacturing facilities which utilize fluid actuated grippers typically have numerous sets of grippers which are designed to transport different workpieces between specific work stations. The requirement of stocking multiple sets of grippers adds to the manufacturer's costs.
The present invention is directed to fluid pressure actuated grippers which overcome and prevent problems associated with fluid pressure leaks or failures. Moreover, the present invention is directed to fluid pressure actuated grippers which are assembled from a plurality of modular or interchangeable components.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Intelligent transport systems (hereafter referred to as “ITS”) have been conceived and have started to be realized; the ITS is a new transport system configured to use a short range communication system called DSRC (Dedicated Short Range Communication; hereafter referred to as “DSRC”) to solve road traffic problems such as traffic accidents and traffic jams. In the ITS, roadside apparatuses installed on a road broadcast information to vehicle-mounted devices mounted in vehicles. Each vehicle-mounted device provides traffic information received from the roadside apparatus to an occupant in the vehicle in the form of voice, still images, or text data at predetermined timings. Attempts have been made to configure roadside apparatuses used in the ITS such that the apparatuses provide vehicle-mounted devices with information varying between the inbound lane and outbound lane of the road. If such information varying between the inbound lane and the outbound lane is provided, traffic information for the inbound lane transmitted by the roadside apparatus may be received by a vehicle-mounted device mounted in a vehicle traveling in the outbound lane, because of leakage, irregular reflection, or the like of electric waves to output the traffic information. In a known technique to solve such a problem, an electric wave absorber is provided at a tollgate on a toll road; the electric wave absorber enables inhibition of the leakage, irregular reflection, or the like of electric waves transmitted by the roadside apparatus (see Patent Document 1).
Patent Document 1: Japanese Patent Application Laid-Open No. 2002-237719 (FIG. 1 and the like)
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Because of the lower aerodynamic drag at high altitudes, a higher cruising altitude of an aircraft fundamentally allows a reduction of the fuel consumption of the aircraft engines. There is therefore a trend towards designing commercial aircraft for flights at increasingly high cruising altitudes of up to 43,000 feet (ca. 13100 m). Commercial aircraft currently in operation comprise a pressurized cabin, the internal pressure of which during cruising is held by means of an air-conditioning system, which is supplied with engine bleed air, at a pressure level that is higher than the ambient pressure, i.e. the reduced atmospheric pressure at high altitudes.
In order to limit the fuselage loads resulting from the pressure difference between the ambient pressure and the higher cabin internal pressure as well as the work that the air-conditioning system has to do in order to maintain the desired pressure level in the interior of the aircraft cabin, the cabin internal pressure of a commercial aircraft during cruising of the aircraft is not held at a pressure level corresponding to the atmospheric pressure at sea level. Rather, the pressure in the interior of the cabin of a commercial aircraft during cruising of the aircraft, i.e. when the aircraft is situated at cruising altitude, usually corresponds approximately to the atmospheric pressure at a height of 8000 feet (ca. 2400 m).
In principle, the oxygen partial pressure of the air in the interior of the aircraft cabin that arises in the case of a cabin internal pressure corresponding approximately to the atmospheric pressure at a height of 8000 feet is high enough to guarantee an adequate supply of oxygen for the crew and passengers on board the aircraft. However, compensating for the pressure difference between the cabin internal pressure during cruising of the aircraft, which corresponds approximately to the atmospheric pressure at a height of 8000 feet, and the pressure level on the ground, which usually corresponds to or lies slightly below the atmospheric pressure at sea level, requires the performance of an adaptation process by the human body. Particularly for persons who react sensitively to a reduced oxygen partial pressure, the performance of this adaptation process may be taxing and lead to symptoms such as dizziness or even fainting. These symptoms may be additionally intensified by some other illness of an affected person or by stress.
Besides the reduced oxygen partial pressure, the low air humidity in the interior of an aircraft cabin may lead to health problems in sensitively reacting persons. In order to minimize the condensing-out of water on the cold outer skin of the fuselage of the aircraft, the air humidity in the aircraft cabin is kept artificially low and in a front fuselage portion of the aircraft is only approximately 5%. Such a low air humidity is generally perceived as uncomfortable and may lead to drying-out and irritation of the mucous membranes.
As a result of the reduced oxygen partial pressure and the low moisture content of the breathing air in the interior of the aircraft cabin, the crew and the passengers of a commercial aircraft during the flight are subject as a whole to increased physical stress. The extent to which a person perceives this stress however depends upon the individual sensitivity of the person to the special ambient conditions on board an aircraft and upon the flying time. The negative effects of the increased physical stress are therefore perceived to a greater extent by persons who react sensitively to a reduced oxygen partial pressure and low air humidity, especially on long-haul flights.
For the improved comfort of crew members and passengers on board an aircraft and in order to prevent health problems that are caused by a reduced oxygen partial pressure in an aircraft cabin, EP 0 808 769 A2 proposes to supply air which is oxygenated by means of an oxygen concentrator to an aircraft cabin. With the aid of the system described in this document the oxygen content of the air to be supplied to the aircraft cabin may be increased to 25 to 35% by volume. The oxygen enrichment system known from EP 0 808 769 A2 makes it possible to increase the well-being of the crew members and the passengers on board the aircraft. What is more, the pressure difference between the ambient pressure during the flight and the raised cabin internal pressure and hence the stresses of the fuselage resulting therefrom may be limited because the raising of the oxygen partial pressure in the aircraft cabin is realized exclusively by means of oxygen enrichment of the air to be supplied to the cabin and not by means of an increase of the cabin pressure.
An important drawback of the system described in EP 0 808 769 A2 is however that in order to increase the oxygen partial pressure in the aircraft cabin a large quantity of oxygen has to be produced. The oxygen concentrator, which is operated permanently under a high load, therefore involves a high maintenance outlay. The individual components of the system as well as the entire system are moreover very heavy. If instead of the oxygen concentrator described in EP 0 808 769 A2 an oxygen reservoir is used to provide the oxygen needed to enrich the air to be supplied to the aircraft cabin, this oxygen reservoir is likewise very heavy and moreover takes up a large amount of installation space.
The underlying object of the invention is therefore to provide a lightweight and compact device for improving the breathing air quality in an aircraft cabin.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
For certain conventional exhaust gas recirculation (EGR) systems, exhaust gas expelled from all of the cylinders of an internal combustion engine may be collected in an exhaust manifold. A fraction of the collected exhaust gas (e.g. 5% to 10%) may then be routed from the exhaust manifold through a control valve back to an intake manifold of the engine, where it may be introduced to a stream of fresh (ambient) intake air. The remaining fraction of exhaust gas in the exhaust manifold, rather than being recirculated and recycled, generally flows to a catalytic converter of the exhaust system and, after treatment therein, may be expelled to the atmosphere through the exhaust pipe.
EGR has a history of use in gasoline spark-ignition engines, and affects combustion in several ways. First, the combustion in the cylinders of the engine may be cooled by the presence of exhaust gas, that is, the recirculated exhaust gas may absorb heat from the combustion. Furthermore, the dilution of the oxygen present in the combustion chamber with the exhaust gas, in combination with the cooler combustion, may reduce the production of mono-nitrogen oxides (NOx), such as nitric oxide (NO) and nitrogen dioxide (NO2). Additionally, EGR may reduce the need for fuel enrichment at high loads in turbocharged engines and thereby improve fuel economy.
EGR which uses higher levels of exhaust gas may further increase fuel efficiency and reduce emissions of spark-ignition engines. However, with higher levels of exhaust gas, engines may face challenges related to EGR tolerance, which may reduce the expected fuel efficiency improvement. Challenges related to EGR tolerance may be understood to include increasing an engine's ability to process higher levels of exhaust gas without adversely affecting performance, particularly fuel economy. Thus, even if EGR tolerance may be satisfactory for engine operation at low levels of EGR, an engine may need additional modifications in structure and operational conditions to accommodate higher levels of EGR without adversely affecting engine performance.
More recently, an engine configuration has been proposed with one or more cylinders of the engine being dedicated to expelling exhaust gas for EGR, which is then directed to the intake manifold. Such cylinders may be referred to as dedicated EGR, or D-EGR, cylinders. Dedicated EGR cylinder(s) may operate at a broad range of equivalence ratios since their exhaust gas is generally not configured to exit the engine before flowing through a cylinder operating at, for example, a stoichiometric or near stoichiometric air/fuel ratio. This may allow the dedicated EGR cylinder to be operated fuel rich to produce higher levels of hydrogen (H2) gas and carbon monoxide (CO) gas and which, may in turn, increase the octane number and promote increased EGR tolerance and knock tolerance by increasing flame/speed burn rates, as well as increasing the dilution limits of the mixture and associated combustion stability of all the cylinders. Examples of engines with a D-EGR cylinder may be found in U.S. Patent Application Publication No. 2012/0204844 entitled “Dedicated EGR Control Strategy For Improved EGR Distribution And Engine Performance” and U.S. Patent Application Publication No. 2012/0204845 entitled “EGR Distributor Apparatus For Dedicated EGR Configuration”, both in the name of Jess W. Gingrich, which are assigned to the assignee of the present disclosure and hereby incorporated by reference.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Technical Field
The present invention is directed to the field of phase locked loops. More specifically, the invention provides an improved phase locked loop ("PLL") that includes a DC bias circuit. The DC bias circuit enables the PLL to operate using a single supply voltage, and also may be used to eliminate the phase discrimination "dead zone" normally associated with the phase detector element of the PLL.
2. Description of the Related Art
Phase locked loops are well-known elements in analog and digital circuit design. A phase locked loop operates by receiving an external reference clock signal and generating a localized oscillator signal that is synchronized with the external reference clock signal. The local oscillator signal may operate at the same frequency as the reference clock signal or at some integer multiple of that frequency. A general description of the theory and operational characteristics of a PLL is contained in Couch, Digital and Analog Communication Systems, Fourth Edition, pp. 289-296.
FIG. 1 is a circuit diagram of a known PLL circuit 10. This circuit 10 includes four primary elements--a phase detector 14, an operational amplifier 26, a voltage controlled oscillator (VCXO) 32, and a counter 36. This circuit 10 generates a local oscillator signal (PLL clock) 34 that is synchronized with an external reference clock signal 12, but which operates at a higher frequency than the external reference clock 12. This is accomplished by feeding back a divided down version 38 of the local oscillator signal 34 to the phase detector 14, which then compares the phases of the reference clock signal 12 with the feedback signal 38.
The phase detector 14 is preferably a phase frequency detector, and has two inputs and two outputs. The two inputs of the phase detector 14 are coupled to the external reference clock signal 12 and the PLL feedback signal 38, and the two outputs 16A, 16B are coupled to the operational amplifier 26. If the PLL feedback signal 38 leads in phase with respect to the reference clock signal 12, then the phase detector 14 outputs a pulse on the negative phase output (ph-) 16A. Similarly, if the reference clock signal 12 leads in phase with respect to the PLL feedback signal 38, then the phase detector 14 outputs a pulse on the positive phase output (ph+) 16B. These output pulses on the positive and negative phase outputs 16A, 16B from the phase detector 14 are characterized by a pulse width that is equivalent to the phase difference between the two inputs.
When the phase difference between the reference clock signal 12 and the PLL feedback signal 38 is nearly zero degrees (i.e., when the PLL is "locked"), then the phase detector enters an operational region in which it cannot discriminate the phase difference between the two input signals. This operational region is referred to herein as the "dead zone." As the phase difference of the two inputs approaches zero degrees, the phase detector 14 outputs minimum-width pulses on both the positive and negative phase outputs 16A, 16B.
The phase detector outputs 16A, 16B are coupled to the operational amplifier 26 through a pair of RC circuits. These RC circuits configure the operational amplifier 26 as an integrator. The negative phase output (ph-) 16A is coupled to the negative input of the operational amplifier 26 through the RC circuit composed of resistors 18, 28 and capacitor 30. And the positive phase output (ph+) 16B is coupled to the positive input of the operational amplifier 26 through the RC circuit composed of resistors 20, 22 and capacitor 24.
This integrator 18-30 receives the pulses from the phase detector outputs (ph+, ph-) 16A, 16B and generates a voltage level at its output that is proportional to the pulse width of the phase pulses. This phase voltage is then provided as an input to the voltage controlled oscillator (VCXO) 32. Because these phase pulses are typically very narrow, particularly when the reference clock signal 12 is very nearly in phase with the PLL feedback signal 38, the voltage output of the operational amplifier is typically near ground. For this reason, the operational amplifier 26 is typically powered using two power supply voltages, such as +/-12 volts or +/-15 volts. This is done because the operational amplifier 26 output becomes non-linear as the output voltage approaches the power supply rails. Thus, it does not operate effectively from a single supply voltage, such as +5V, where the other supply rail is ground, since the phase voltage is typically very close to ground when the PLL is in the locked condition.
The voltage controlled oscillator 32 generates an output clock signal, PLL clock 34, which is characterized by a frequency that is proportional to the phase voltage from the integrator. This clock signal, PLL clock 34, is the localized oscillator signal that is synchronized with the external reference clock 12. The PLL clock signal 34 is then fed back to one of the inputs of the phase detector 14 either directly, or via a counter 36.
The counter 36 is configured as a divide-by-N counter, and it generates the PLL feedback signal 38, which is a frequency divided version of the PLL clock signal 34. By selecting an appropriate value of N, a circuit designer can select the frequency of the PLL clock signal 34 with respect to the external reference clock 12. For example, if the circuit designer desires to generate a synchronized version of the reference clock signal 12, but at a frequency 10 times greater than the reference clock signal 12, then the value of N would be 10.
FIG. 2 is a timing diagram showing the operation of the PLL set forth in FIG. 1. This timing diagram sets forth, from top to bottom, the PLL clock signal 34, the reference clock signal 12, the PLL feedback signal 38, and the corresponding phase pulse signals on the positive and negative phase outputs 16B, 16A of the phase detector 14. As seen in this diagram, during normal operation (i.e., when the PLL is locked), the PLL clock signal 34 is in phase with the reference clock 12, but at a higher frequency. The PLL feedback signal 38 is nearly identical to the external reference clock signal 12 when the circuit is locked, and is in phase with this signal. When locking occurs, the phase difference between the PLL feedback signal 38 and the reference clock signal 12 is very small, and the phase detector 14 enters the "dead zone" region in which it cannot further discriminate between the phase difference of the two input signals 12, 38. In this region, the phase detector 14 outputs two extremely narrow pulses at the positive and negative phase outputs 16B, 16A, during the rising edge of the input clocks 12, 38.
The circuit shown in FIG. 1 suffers from two problems. The first problem relates to the dead zone. As described above, at some point during the locking of the PLL, the phase difference between the reference clock signal 12 and the feedback signal 38 becomes so small that the phase detector 14 cannot determine which signal is leading or lagging the other signal. This dead zone region thus presents a minimum threshold phase difference below which the PLL cannot properly lock. Although the characteristics of the phase detector circuitry 14 generally determine the extent of the dead zone region, the minimum threshold difference represented by this region may also be affected by component variations and tolerances in the external RC elements 18-24, 28-30 of the integrator.
The second problem with the circuit shown in FIG. 1 relates to the operational amplifier 26 power scheme. As described above, because the positive and negative phase outputs 16A, 16B of the phase detector 14 are typically very narrow pulses, particularly as the PLL approaches a locked condition, the output voltage of the integrator circuit is typically near zero volts (ground). Because of this very small output voltage, and also because an operational amplifier does not exhibit linear characteristics near its power rails, this requires that the operational amplifier 26 is powered using a plus/minus power supply scheme, such as +/-15 volts. This presents a problem when the apparatus in which the PLL circuit 10 is employed includes only a single power supply, such as +5V.
Therefore, there remains a need in this field for an improved PLL circuit that overcomes the problems noted herein.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Unmanned aerial vehicles (UAVs), also known as UAVs, have become increasingly popular. The use of UAVs spans from small-scale hobby use to large-scale military operations. Because of the widespread use, UAVs of all shapes and sizes are constructed for a myriad function. Among the popular functions of UAVs are photography and package delivery, to name a couple.
Because of possible collision with other aircraft and obstacles due to an inability to see-and-avoid, UAVs are typically designed and operated to achieve their specific functionality as a single unit. Thus, while occupying a particular airspace, a UAV operator or the UAV itself, if flying autonomously, will maneuver as necessary to avoid other UAVs, aircraft, and obstacles in the sky.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
It is well-recognized that cancer is a scourge of the modern world, particularly of the developed nations. According to one estimate, in such countries out of a population of 100,000, up to 20,000 people can be expected to contract cancer and fail to get effective treatment. As reported in Vol. 1 of "Dynamics and Opportunities in Cancer Management" by SRI International (1985), page 6, about 5 million persons are likely to die of cancer in 1986. This is particularly devastating in view of the pain and incapacity which precedes actual death by cancer.
It is not surprising, therefore, that much attention is being given to discovering anti-tumor agents. The need for effective anti-tumor agents is so well-known that, whenever it is rumored that one has been found, the press and the public clamor for information.
One problem with conventional chemotherapeutic drugs in the treatment of cancer has been that such drugs tend to be highly toxic to healthy cells as well as to cancer cells. As a result, they produce undesirable side effects, such as alopecia (hair loss), emisis (nausea), nephrotoxicity, cardiotoxicity, etc. Another problem has been the relative lack of success when using even the most popular drugs. For example, "Adriamycin".TM., identified hereinafter, has had only a 14.5% effective response rate in treating stomach cancer in Japan, as reported in Antibiotics Chemother., Vol. 24, pages 149-159 (1978).
Yet, so severe is the problem of cancer that people take such drugs and suffer such side-effects in the hope that the cancer will be alleviated before the side-effects become unbearable. There is currently available some selectivity in toxicity, that is, the ability of the chemotherapeutic agent to selectively kill carcinoma cells instead of healthy cells. However, for most such conventional chemotherapeutic agents that selectivity does not exceed 2 or 3 as defined, for example, by the IC.sub.50 values in in vitro studies of human carcinomas. Such conventional selectivity of 2 or 3 is not adequate because undesirable side effects still plague the patient. Selectivity values defined by the IC.sub.50 ratios of at least 5 to 1 are needed before the selectivity becomes significant enough to predict reduced undesirable side effects.
Therefore, a chemotherapeutic drug having significant selective toxicity to at least some types of cancer is a long-felt need that begs for a solution. This need particularly exists in the arena of differentiated carcinomas, since as explained in Discover, March, 1986, page 37, such constitute about 85% of the cancers. Such carcinomas include cancer of the so-called "hollow" organs: the breast, colon, bladder, lung, prostate, stomach and pancreas. Colon carcinomas are particularly in need of effective chemotherapeutic agents, since at present no known drug is very effective against this cancer. (Discover, March, 1986, pages 36-46, at page 38).
Thiapyryliums, and particularly 2,4,6-triphenylthiapyrylium perchlorates are known to have anti-microbial and anti-phage activities. These are described in e.g., Khim-farm. ZH., Vol. 15, No. 11 pp. 38-40 (1981). However, there is no suggestion anywhere that these thiapyryliums will provide anti-cancer activity.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention relates to a display device, a color filter substrate and a manufacturing method thereof.
Color filter substrate (CF) is an important component of a thin film transistor liquid crystal display (TFT-LCD). A liquid crystal display mainly depends on the color filter substrate to be able to present colorful images. White light from the backlight transmits through the liquid crystal layer and irradiates on the color filter substrate. Then it passes through red, green and blue color filters corresponding to each pixel on the color filter substrate and form red, green and blue lights. They are finally mixed into color images in human eyes. The color filter substrate accounts for significant costs in a TFT-LCD display panel. For a 15 in. panel, the color filter substrate accounts for about 24% in terms of material cost. It's convenient to realize color display with color filter substrates and it is possible to obtain quite high color purity and relatively wide color reproduction range, therefore this manner has become a dominant manner for multi-colorized or full colorized liquid crystal displays.
As shown in FIG. 1, a conventional color filter substrate includes: a substrate 1; a black matrix 2 formed on the substrate 1; a color resin layer 3 formed in exposed pixel regions of the black matrix 2, which includes a red resin layer (R, denoted by right oblique lines in the figure), a green resin layer (G, denoted by mesh lines in the figure) and a blue resin layer (B, denoted by left oblique lines in the figure); a planarization layer 4 formed on the substrate 1 with the color resin layer 3 formed thereon; and spacer (PS) 5 formed on the planarization layer 4. In case of a twisted nematic (TN) liquid crystal panel, a transparent conductive layer (not shown in Figs.) is further disposed in the color filter substrate, which is over the planarization layer 4 and on which is formed the spacer 5.
With the development of TFT-LCD technology, the requirement on transmissivity of the color filter substrate is becoming higher and higher. As shown in FIG. 2, in order to improve transmissivity of the color filter substrate, a solution is proposed to design light holes 6 in the color resin layer 3, wherein light holes 6 may be adjusted in their sizes as required, which occupy about 3%˜4% area of the sub-pixel area.
When the color filter substrate is designed with light holes, in the conventional process, an over coat (OC) is typically applied on the black matrix and the color resin layer to form the planarization layer of the color filter substrate and depressions at light holes are filled with the OC material. However, as shown in FIG. 3, while forming the planarization layer 4, due to insufficient filling of OC material at the light holes 6, collapses 7 and too big steps would occur at light holes 6, causing poor alignment of liquid crystal.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to an ferrodielectric liquid crystal display (FLCD) manufacturing method and, more particularly, to an FLCD manufacturing method capable of forming a ferrodielectric crystal in a uniform mono domain upon a bookshelf-structured crystalization to enhance image quality.
The present application is based on Korean Patent Application No. 2002-18086 filed on Apr. 2, 2002, which is incorporated herein by reference in its entirety.
2. Description of the Prior Art
The LCD is a flat-type display device use of which is wide spread. The LCD is used mainly for portable devices and is also replacing conventional cathode-ray tubes (CRTs) in the field of large-sized display devices with the developments of display-enlarging technologies.
There exist various kinds of crystal materials applied to form the LCD.
The twisted nematic (hereinafter referred to as “TN”) LCD employed a lot in general applications uses the interactions between the dielectric anisotropy of the TN liquid crystal molecules and the electric field to slow down a response time in tens of miliseconds (ms) so that it has difficulties in displaying animations, has a narrow visual angle, and generates cross-talk among pixels within a certain distance, to thereby cause a problem of difficulties in reducing a pixel size below a certain size.
Meanwhile, the FLCD uses the interactions between spontaneous polarization of the ferrodielectric liquid crystal and the electric field and provides rapid response characteristics below 1 ms. Such an FLCD, as a next generation display device, has no difficulties in displaying animations, is capable of providing a wide visual angle, and can implement a high resolution with a more reduced pixel size preventing cross-talk from occurring due to strong interactions between molecules, so that research into the FLCD is actively progressing.
For the ferrodielectric liquid crystal widely employed at present, there is a chiral smectic C phase (SmC*) liquid crystal material having bistable characteristics and a chevron structure.
For the FLCD using the liquid crystal material, in the manufacturing process, crystal maintained at a temperature over the melting point is injected in a cell between the substrates, the crystal turns to its smectic A phase having a layer structure perpendicular to the rubbing direction via a chiral nematic (N*) phase when the temperature is lowered down, and then turns to the chiral smectic C phase. In the process, the molecular long axes of liquid crystal molecules in the liquid crystal layer is tilted at a particular angle to the rubbing direction to decrease a distance between smectic layers, as a result of which the bent of the smectic layer is induced in the liquid crystal layer to compensate a volume change. Such a bent layer structure is referred to as a chevron structure, and a domain having different long axis directions of the liquid crystal based on the bent direction is formed, and on the interface of which non-uniform orientations having zigzag defects, hairpin defects, mountain defects, and so on are obtained.
A contrast ratio of an LCD is remarkably deteriorated with such orientation characteristics, and, if a dc voltage is forced to be applied against it, ions in the liquid crystal layer are stacked up or absorbed on the surface of an orientation film to cause a problem that produces a residual image phenomenon faintly displaying a preceding image pattern as one display is changed to the next one.
Besides, research is actively being carried out on ferrodielectric liquid crystal materials which provide an anti-ferrodielectric liquid crystal (AFLC) mode alleviating a threshold limitation, but its spontaneous polarization is more than 100 nC/cm2 so that a residual image may also occur due to ion movements caused by an inverse polarization electric field. Further, in case of applying the active matrix driving approach which is an approach for each pixel to independently drive a liquid crystal by using thin film transistors (TFTs), leakage currents may occur owing to big spontaneous polarizations. Capacitors should be very large in capacity in order to restrain the leakage current of the AFLC, which reduces an aperture ratio to cause a problem of difficulties in using the AFLC as a display device.
In order to improve the drawback to such a ferrodielectric liquid crystal, ferrodielectric liquid substances have been continuously developed which have a bookshelf structure enabling alternate current driving and restraining residual images.
There is a crystal substance, as a ferrodielectric liquid crystal substance having the bookshelf structure in the spotlight at present, which has skipped the smectic A phase in the crystalization process. That is, in the crystalization process, the phase transition for the crystalization is undergone from an isotropic fluid state to a chiral nematic (N*) phase to a chiral smectic C (SmC*) phase. Of the liquid crystals transiting phases from the chiral nematic phase to the chiral smectic C phase, there is a half-V type liquid crystal having a monostable characteristic.
In the half-V type liquid crystal, the optical axis is positioned in a parallel direction with a rubbing direction of the orientation film when any electric potential is not applied, as shown in FIG. 1, and, when a positive voltage (+) is applied, the long axis of the liquid crystal is tilted up to 45 degrees at maximum in correspondence with a level of the electric potential applied. In FIG. 1, Vsat denotes a saturation voltage which produces a maximum tilt for the liquid crystal.
Further, with an application of a negative voltage, the long axis of the liquid crystal is aligned in the same direction as when no potential is applied. The light transmittance of such a liquid crystal has a relationship as shown in FIG. 2, that is, a monostable characteristic with respect to an applied voltage. The liquid crystal having such a characteristic has several names, but is generally referred to as a half-V type liquid crystal, particularly considering the applied potential (V)-to-light transmittance (T) characteristic.
In particular, such a liquid crystal enables alternative current driving and analog gray scale displays for easy full-color implementations, and enables pulse driving due to the monostable characteristic, to thereby have an advantage of providing a display performance close to the existing CRT display.
However, the FLCD of the bookshelf structure which is manufactured with the conventional cooling has layer contractions occurring during the increase of a tilt angle of liquid crystal molecules when in the phase transition from the chiral nematic phase to the chiral smectic C phase in a process of the crystalization of liquid crystal, causing a problem of forming non-uniform domains in an alignment process of liquid crystal for compensating the layer contraction so that bright differences are brought out in a display state.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Zavada et al., International Publication Number WO 93/18152 (published 16 Sep. 1993) and U.S. Pat. No. 5,387,676 (issued Feb. 7, 1995), describe the discovery and biological and molecular nature of the MN gene and protein. The MN gene was found to be present in the chromosomal DNA of all vertebrates tested, and its expression to be strongly correlated with tumorigenicity.
The MN protein was first identified in HeLa cells, derived from a human carcinoma of cervix uteri. It is found in many types of human carcinomas (notably uterine cervical, ovarian, endometrial, renal, bladder, breast, colorectal, lung, esophageal, and prostate, among others). Very few normal tissues have been found to express MN protein to any significant degree. Those MN-expressing normal tissues include the human gastric mucosa and gallbladder epithelium, and some other normal tissues of the alimentary tract. Paradoxically, MN gene expression has been found to be lost or reduced in carcinomas and other preneoplastic/neoplastic diseases in some tissues that normally express MN, e.g., gastric mucosa.
In general, oncogenesis may be signified by the abnormal expression of MN protein. For example, oncogenesis may be signified: (1) when MN protein is present in a tissue which normally does not express MN protein to any significant degree; (2) when MN protein is absent from a tissue that normally expresses it; (3) when MN gene expression is at a significantly increased level, or at a significantly reduced level from that normally expressed in a tissue; or (4) when MN protein is expressed in an abnormal location within a cell.
Zavada et al., WO 93/18152 and Zavada et al., WO 95/34650 (published 21 Dec. 1995) disclose how the discovery of the MN gene and protein and the strong association of MN gene expression and tumorigenicity led to the creation of methods that are both diagnostic/prognostic and therapeutic for cancer and precancerous conditions. Methods and compositions were provided therein for identifying the onset and presence of neoplastic disease by detecting or detecting and quantitating abnormal MN gene expression in vertebrates. Abnormal MN gene expression can be detected or detected and quantitated by a variety of conventional assays in vertebrate samples, for example, by immunoassays using MN-specific antibodies to detect or detect and quantitate MN antigen, by hybridization assays or by PCR assays, such as RT-PCR, using MN nucleic acids, such as, MN cDNA, to detect or detect and quantitate MN nucleic acids, such as, MN mRNA.
Zavada et al, WO 93/18152 and WO 95/34650 describe the production of MN-specific antibodies. A representative and preferred MN-specific antibody, the monoclonal antibody M75 (Mab M75), was deposited at the American Type Culture Collection (ATCC) in Manassus, Va. (USA) under ATCC Number HB 11128. The M75 antibody was used to discover and identify the MN protein and can be used to identify readily MN antigen in Western blots, in radioimmunoassays and immunohistochemically, for example, in tissue samples that are fresh, frozen, or formalin-, alcohol-, acetone- or otherwise fixed and/or paraffin-embedded and deparaffinized. Another representative and preferred MN-specific antibody, Mab MN12, is secreted by the hybridoma MN 12.2.2, which was deposited at the ATCC under the designation HB 11647. Example 1 of Zavada et al., WO 95/34650 provides representative results from immunohistochemical staining of tissues using MAb M75, which results support the designation of the MN gene as an oncogene.
Many studies have confirmed the diagnostic/prognostic utility of MN. The following articles discuss the use of the MN-specific MAb M75 in diagnosing/prognosing precancerous and cancerous cervical lesions: Leff, D. N., “Half a Century of HeLa Cells: Transatlantic Antigen Enhances Reliability of Cervical Cancer Pap Test, Clinical Trials Pending,” BioWorld 7 Today: The Daily Biotechnology Newspaper, 9(55) (Mar. 24, 1998); Stanbridge, E. J., “Cervical marker can help resolve ambiguous Pap smears,” Diagnostics Intelligence, 10(5): 11 (1998); Liao and Stanbridge, “Expression of the MN Antigen in Cervical Papanicolaou Smears Is an Early Diagnostic Biomarker of Cervical Dysplasia,” Cancer Epidemiology, Biomarkers & Prevention, 5: 549-557 (1996); Brewer et al., “A Study of Biomarkers in Cervical Carcinoma and Clinical Correlation of the Novel Biomarker MN,” Gynecologic Oncology, 63: 337-344 (1996); and Liao et al., “Identification of the MN Antigen as a Diagnostic Biomarker of Cervical Intraepithelial Squamous and Glandular Neoplasia and Cervical Carcinomas,” American Journal of Pathology, 145(3): 598-609 (1994).
Premalignant and Malignant Colorectal Lesions. MN has been detected in normal gastric, intestinal, and biliary mucosa. [Pastorekova et al., Gastroenterology, 112: 398-408 (1997).] Immunohistochemical analysis of the normal large intestine revealed moderate staining in the proximal colon, with the reaction becoming weaker distally. The staining was confined to the basolateral surfaces of the cryptal epithelial cells, the area of greatest proliferative capacity. As MN is much more abundant in the proliferating cryptal epithelium than in the upper part of the mucosa, it may play a role in control of the proliferation and differentiation of intestinal epithelial cells. Cell proliferation increases abnormally in premalignant and malignant lesions of the colorectal epithelium, and therefore, is considered an indicator of colorectal tumor progression. [Risio, M., J. Cell Biochem, 16G: 79-87 (1992); and Moss et al., Gastroenterology, 111: 1425-1432 (1996).]
The MN protein is now considered to be the first tumor-associated carbonic anhydrase (CA) isoenzyme that has been described. Carbonic anhydrases (CAs) form a large family of genes encoding zinc metalloenzymes of great physiological importance. As catalysts of reversible hydration of carbon dioxide, these enzymes participate in a variety of biological processes, including respiration, calcification, acid-base balance, bone resorption, formation of aqueous humor, cerebrospinal fluid, saliva and gastric acid [reviewed in Dodgson et al., The Carbonic Anhydrases, Plenum Press, New York-London, pp. 398 (1991)]. CAs are widely distributed in different living organisms.
In mammals, at least seven isoenzymes (CA I-VII) and a few CA-related proteins (CARP/CA VIII, RPTP-β, RPTP-T) had been identified [Hewett-Emmett and Tashian, Mol. Phyl. Evol., 5: 50-77 (1996)], when analysis of the MN deduced amino acid sequence revealed a striking homology between the central part of the MN protein and carbonic anhydrases, with the conserved zinc-binding site as well as the enzyme's active center. Then MN protein was found to bind zinc and to have CA activity. Based on that data, the MN protein is now considered to be the ninth carbonic anhydrase isoenzyme—MN/CA IX. [Opaysky et al., Genomics, 33: 480-487 (May 1996)]. [See also, Hewett-Emmett, supra, wherein CA IX is suggested as a nomenclatural designation.]
CAs and CA-related proteins show extensive diversity in both their tissue distribution and in their putative or established biological functions [Tashian, R. E., Adv. in Genetics, 30: 321-356 (1992)]. Some of the CAs are expressed in almost all tissues (CA II), while the expression of others appears to be more restricted (CA VI and CA VII in salivary glands). In cells, they may reside in the cytoplasm (CA I, CA II, CA III, and CA VII), in mitochondria (CA V), in secretory granules (CA VI), or they may associate with membrane (CA IV). Occasionally, nuclear localization of some isoenzymes has been noted [Parkkila et al., Gut, 35: 646-650 (1994); Parkkilla et al., Histochem. J., 27: 133-138 (1995); Mori et al., Gastroenterol., 105: 820-826 (1993)].
The CAs and CA-related proteins also differ in kinetic properties and susceptibility to inhibitors [Sly and Hu, Annu. Rev. Biochem., 64: 375-401 (1995)]. In the alimentary tract, carbonic anhydrase activity is involved in many important functions, such as saliva secretion, production of gastric acid, pancreatic juice and bile, intestinal water and ion transport, fatty acid uptake and biogenesis in the liver. At least seven CA isoenzymes have been demonstrated in different regions of the alimentary tract. However, biochemical, histochemical and immunocytochemical studies have revealed a considerable heterogeneity in their levels and distribution [Swensen, E. R., “Distribution and functions of carbonic anhydrase in the gastrointestinal tract,” In: The Carbonic Anhydrases. Cellular Physiology and Molecular Genetics, (Dodgson et al. eds.) Plenum Press, New York, pages 265-287 (1991); and Parkkila and Parkkila, Scan J. Gastroenterol., 31: 305-317 (1996)]. While CA II is found along the entire alimentary canal, CA IV is linked to the lower gastrointestinal tract, CA I, III and V are present in only a few tissues, and the expression of CA VI and VII is restricted to salivary glands [Parkkila et al., Gut, 35: 646-650 (1994); Fleming et al., J. Clin. Invest., 96: 2907-2913 (1995); Parkkila et al., Hepatology, 24: 104 (1996)].
MN/CA IX has a number of properties that distinguish it from other known CA isoenzymes and evince its relevance to oncogenesis. Those properties include its density dependent expression in cell culture (e.g., HeLa cells), its correlation with the tumorigenic phenotype of somatic cell hybrids between HeLa and normal human fibroblasts, its close association with several human carcinomas and its absence from corresponding normal tissues [e.g., Zavada et al., Int. J. Cancer, 54: 268-274 (1993); Pastorekova et al., Virology, 187: 620-626 (1992); Liao et al., Am. J. Pathol., 145: 598-609 (1994); Pastorek et al., Oncogene, 9: 2788-2888 (1994); Cote, Women's Health Weekly: News Section, p. 7 (Mar. 30, 1998); Liao et al., Cancer Res., 57: 2827 (1997); Vermylen et al., “Expression of the MN antigen as a biomarker of lung carcinoma and associated precancerous conditions,” Proceedings AACR, 39: 334 (1998); McKiernan et al., Cancer Res., 57: 2362 (1997); and Turner et al., Hum. Pathol., 28(6): 740 (1997)]. In addition, the in vitro transformation potential of MN/CA IX cDNA has been demonstrated in NIH 3T3 fibroblasts [Pastorek et al., id.].
The MN protein has also been identified with the G250 antigen. Uemura et al., “Expression of Tumor-Associated Antigen MN/G250 in Urologic Carcinoma: Potential Therapeutic Target,” J. Urol., 157 (4 Suppl.): 377 (Abstract 1475; 1997) states: “Sequence analysis and database searching revealed that G250 antigen is identical to MN, a human tumor-associated antigen identified in cervical carcinoma (Pastorek et al., 1994).”
MN/CA IX has been identified as a novel hypoxia regulated marker in invasive breast cancer as reported in Chia et al., “Prognostic Significance of a Novel Hypoxia Regulated Marker, Carbonic Anhydrase IX (MN/CAIX) in Invasive Breast Cancer,” Breast Cancer Research and Treatment, 64(1): 43 (November 2000). Chia et al. stated “that MN/CA IX expression is significantly increased in hypoxic conditions across various cell lines.” MN/CA IX expression was “found to be significantly associated with a higher tumor grade (p=0.003), a negative estrogen receptor status (P<0.001) and tumor necrosis (p<0.001) . . . associated with significantly worst relapse-free survival (p=0.004) and a worse overall survival (p=0.001).”
Hypoxia is a reduction in the normal level of tissue oxygen tension. It occurs during acute and chronic vascular disease, pulmonary disease and cancer, and produces cell death if prolonged. Pathways that are regulated by hypoxia include angiogenesis, glycolysis, growth-factor signaling, immortalization, genetic instability, tissue invasion and metastasis, apoptosis and pH regulation. [Harris, A. L., Nature Reviews, 2: 38-47 (January 2002).]
Tumors become hypoxic because new blood vessels that develop in the tumors are aberrant and have poor blood flow. Although hypoxia is toxic to both tumor cells and normal cells, tumor cells undergo genetic and adaptive changes that allow them to survive and even proliferate in a hypoxic environment. These processes contribute to the malignant phenotype and to aggressive tumor behavior. Hypoxia is associated with resistance to radiation therapy and chemotherapy, but is also associated with poor outcome regardless of treatment modality, indicating that it might be an important therapeutic target. Additionally, there is a need to find an alternative to the current Eppendorf pO2 histograph method for assessing tumor hypoxia in patients. Although the Eppendorf method provides prognostic information in a variety of tumor types, it is limited to tumors acceptable for microneedle insertion. [Harris, A. L., id.]
The central mediator of transcriptional up-regulation of a number of genes during hypoxia is the transcription factor HIF-1. HIF-1 is a heterodimer that consists of the hypoxic response factor HIF-1α and the constitutively expressed aryl hydrocarbon receptor nuclear translocator (ARNT, also known as HIF-1β). In the absence of oxygen, HIF-1 binds to HIF-binding sites within hypoxia-response elements (HREs) of oxygen-regulated genes, thereby activating the expression of numerous hypoxia-response genes, such as erythropoietin (EPO), and the proangiogenic growth factor vascular endothelial growth factor (VEGF).
Semenza et al. PNAS (USA), 88: 5680-5684 (1991) first identified cis-activating DNA sequences that function as tissue-specific hypoxia-inducible enhancers of human erythropoietin expression. Pugh et al., PNAS (USA), 88: 10533-71 (1991) isolated such a DNA sequence 3′ to the mouse erythropoietin gene which acts as a hypoxia-inducible enhancer for a variety of heterologous promoters. Maxwell et al., PNAS (USA), 90: 2423-2427 (1993) have shown that the oxygen-sensing system which controls erythropoietin expression is widespread in mammalian cells.
McBurney et al., Nucleic Acids Res., 19: 5755-61 (1991) found that repeating the hypoxia response element (HRE) sequence, located 5′ to the hypoxia-inducible mouse phosphoglycerate kinase gene (PGK), leads to increased induction of the gene, and that using the interleukin-2 gene under tissue-specific promoters can be used for specific targeting of tumors.
Hypoxia can be used to activate therapeutic gene delivery to specific areas of tissue. Dachs et al. “Targeting gene expression to hypoxic tumor cells,” Nat. Med., 3: 515-20 (1997) has used the HRE from the mouse PGK gene promoter to drive expression of heterologous genes both in vitro and in vivo with controlled hypoxia.
For some HIF targets such as VEGF, a clear function in promoting tumor growth is established. [Kim et al., “Inhibition of vascular endothelial growth factor-induced angiogenesis suppresses tumour growth in vivo,” Nature (Lond.), 362: 841-844 (1993).] However, the full range of HIF target genes has not yet been defined, and identification of additional genes responding to this pathway is likely to provide further insights into the consequences of tumor hypoxia and HIF activation.
Indirect support for the importance of microenvironmental activation of HIF has also been provided by recent demonstrations of constitutive activation of HIF after inactivation of the VHL tumor suppressor gene. [Maxwell et al., “The tumour suppressor protein VHL targets hypoxia-inducible factors for oxygen-dependent proteolysis,” Nature (Lond.), 399: 271-275 (1999)] and amplification of the HIF response by other oncogenic mutations. [Jiang et al., “V-SRC induces expression of hypoxia-inducible factor 1 (HIF-1) and transcription of genes encoding vascular endothelial growth factor and enolase 1: involvement of HIF-1 in tumor progression,” Cancer Res., 57: 5328-5335 (1997); Blagosklonny et al., “p53 inhibits hypoxia-inducible factor-stimulated transcription,” J. Biol. Chem., 273: 11995-11998 (1998); Ravi et al., “Regulation of tumor angiogenesis by p53-induced degradation of hypoxia-inducible factor 1α,” Genes Dev., 14: 34-44 (2000); Zundel et al., “Loss of PTEN facilitates HIF-1 mediated gene expression,” Genes Dev., 14: 391-396 (2000).]
Mutations in VHL cause the familial syndrome and are also found in the majority of sporadic RCCs. [Gnarra et al., “Mutations of the VHL tumour suppressor gene in renal carcinoma,” Nat. Genet., 7: 85-90 (1994).] The gene product pVHL forms part of ubiquitin-ligase complex, [Lisztwan et al., “The von Hippel-Landau tumor suppressor protein is a component of an E3 ubiquitin-protein ligase activity,” Genes Dev., 13: 1822-1833 (1999); Iwai et al., “Identification of the von Hippel-Lindau tumor-suppressor protein as part of an active E3 ubiquitin ligase complex,” Proc. Natl. Acad. Sci. (USA) 96: 12436-12441 (1999)] that targets HIF-α subunits for oxygen-dependent proteolysis. [Maxwell et al., (1999) supra; Cockman et al., “Hypoxia inducible factor-α binding and ubiquitination by the von Hippel-Landau tumor suppressor protein,” J. Biol. Chem., 275: 25733-25741 (2000).]
In VHL-defective cells, HIF-α is stabilized constitutively, resulting in up-regulation of hypoxia-inducible genes such as VEGF. [Maxwell et al., (1999) supra.] Although the pVHL ubiquitinligase complex may have other targets [Iwai et al., supra] and other functions of pVHL have been proposed that may contribute to tumor suppressor effects [Pause et al., “The von Hippel-Lindau tumor suppressor gene is required for cell cycle exit on serum withdrawal,” Proc. Natl. Acad. Sci. (USA) 95: 993-998 (1998); Ohh et al., “The von Hippel-Landau tumor suppressor protein is required for proper assembly of an extracellular fibronectin matrix,” Mol. Cell. 1: 959-968 (1998)], these recent findings raise important questions as to the range of genes affected by constitutive HIF activation and role of such genes in oncogenesis.
In that respect, MN/CA 9 considered to be an oncogene has an interesting position as a transmembrane carbonic anhydrase (CA). CAs catalyze the reversible hydration of carbon dioxide to carbonic acid [Sly et al., Annu. Rev. Biochem., 64: 375-401 (1995)], providing a potential link between metabolism and pH regulation. One aspect of this invention is the relationship between MN/CA 9 and hypoxia. MN/CA IX is shown to be one of the most strongly hypoxia-inducible proteins.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of Invention
The present invention relates to technology for the drive circuit of a plasma display device for use in a wall-hanging television set or a large monitor, more particularly, to a plasma display panel drive circuit and a plasma display device.
2. Description of Related Art
An alternating current surface discharge plasma display panel (hereafter referred to as “PDP”) being typical as an AC-type comprises a front panel formed of a glass substrate on which scan electrodes and sustain electrodes for carrying out surface discharge are arranged and a rear panel formed of a glass substrate on which data electrodes are arranged. The scan electrodes and the sustain electrodes are disposed in parallel so as to be opposed to the data electrodes, and the scan electrodes, the sustain electrodes and the data electrodes are arranged so as to construct a matrix and to form a discharge space in the clearance. The outer circumferential portions of the panels are sealed with a sealing agent, such as glass frit. Furthermore, discharge cells partitioned by partition walls are provided between both the substrates of the front panel and the rear panel, and phosphor layers are formed in the cell spaces between the partition walls. In the PDP configured as described above, ultraviolet light is generated by gas discharge, and the ultraviolet light excites the red (R), green (G) and black (B) phosphors to emit light for color display.
In this kind of plasma display device, the charging characteristics inside the panel depend on the ambient temperature of the panel, and differences occur in the charged state among the cells depend on the display pattern. Hence, the conventional drive method has a first problem that addressing errors (no discharge in addressed cells) due to excessive or insufficient charge in the inter-electrode space AY between the data electrodes A and the scan electrodes Y are apt to occur.
FIG. 14 shows the writing period of a sub-field. In addition, FIGS. 15A and 15B schematically show the states of the wall charges inside a cell at lines L1 and L2 shown in FIG. 14, respectively. The distribution of the wall charges in the discharge cell at line L1 shown in FIG. 14 is as shown in FIG. 15A. Since the state obtained immediately after the end of the setup period is shown in FIG. 15A, negative wall charges are accumulated sufficiently on the scan electrode SCN, and positive wall charges are accumulated sufficiently on the sustain electrode SUS and the data electrode DATA. On the other hand, the distribution of the wall charges in the discharge cell at line L2 shown in FIG. 14 is as shown in FIG. 15B, and the wall charges distributed on the respective electrodes are reduced in comparison with the state shown in FIG. 15A.
Priming particles floating in a discharge cell space due to setup or sustain discharge and electrons, etc. emitted from MgO activated due to sustain discharge are accelerated by the electric field inside a discharge cell waiting for writing. Hence, the wall charges accumulated by setup are neutralized gradually, and the wall charges on the respective electrodes are reduced as shown in FIG. 15B. If the writing operation is carried out in the state shown in FIG. 15A, discharge delay is decreased because the wall charges and the priming particles are sufficient, whereby favorable writing discharge is made possible. However, if the writing operation is carried out in the state shown in FIG. 15B, discharge delay is increased because both the wall charges and the priming particles are insufficient, whereby writing errors occur frequently and favorable picture quality cannot be obtained. This is a second problem.
To prevent the deterioration of picture quality due to the two problems described above, a method of weakening the electric field inside a discharge cell waiting for writing and suppressing the neutralization of wall charges is taken by raising the scan pulse voltage Vscn. FIG. 16 is a view showing an example of the relationship of the scan pulse voltage Vscn with respect to write-waiting time (the relationship being different depending on the drive method and the panel). The write-waiting time is herein a value represented by multiplying the number n of the scan electrode by the time for one scan pulse. The scan pulse voltage Vscn is higher as the ambient temperature becomes higher and as the write-waiting time becomes longer. Since the upper limit of the scan pulse voltage Vscn is determined by the withstand voltage of the drive circuit for use in the scan electrode drive circuit, such a drivable range as shown in FIG. 16 is present. As the resolution becomes higher to conform to the full high-vision, super high-vision (2 k×4 k), etc. in recent years, the write-waiting time increases abruptly, and the driving in the drivable range becomes difficult.
Accordingly, address drive methods have been disclosed to attain addressing that hardly causes errors even when the ambient temperature is high and to stabilize display without increasing the withstand voltage of the scan electrode drive circuit (for example, refer to the specification of U.S. Patent Application Publication No. 2001/0028225A1). The PDP drive device disclosed in the specification of U.S. Patent Application Publication No. 2001/0028225A1 has a scan electrode drive circuit and a sustain electrode drive circuit. The scan electrode drive circuit is provided with sustain pulse generating circuits, setup waveform generating circuits and scan pulse generating circuits, the numbers of which correspond to the number of panel divisions.
In the configuration described in the specification of U.S. Patent Application Publication No. 200110028225A1, multiple sustain pulse generating circuits and multiple setup waveform generating circuits are required. Hence, the number of components and the mounting areas of the components increase, and the cost required for the configuration increases. Furthermore, the configuration is applied to a case in which the panel is divided into two blocks and addressing is performed. If it is assumed that the panel is divided into n blocks, the results in that n pieces of sustain pulse generating circuits and n pieces of setup waveform generating circuits are required.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Perchlorinated quinones are well known in the art providing a variety of uses in both the chemical and pharmaceutical industries. For example, chloranil (2, 3, 5, 6-tetrachloro-p-benzoquinone) is a powerful oxidant which has been used in the oxidation and dehydrogenation of a large number of organic compounds. It is used commercially as an oxidizing agent in the preparation of dyes such as methyl violet and as a fungicide in agricultural applications. Chloranil is also known to be a useful reagent for tamaquine detection in urine.
Various industrial processes exist for the manufacture of chloranil. U.S. Pat. No. 2,722,537 (Fox) discloses a process for the preparation of chloranil through oxidative chlorination of cyclohexane using hydrogen chloride and oxygen at a temperature between 180.degree. and 260.degree. C. U.S. Pat. No. 2,414,008 (Alquist et. al.) discloses the production of chloranil by admixing a polychlorophenol with concentrated sulfuric acid and passing chlorine into the heated mixture. U.S. Pat. No. 2,422,229 (Fletcher) discloses a process for manufacturing chlorinated quinones by chlorination of derivatives of phenol and alphahydroxynapthalene, the derivatives being present in a liquid medium comprising a mixture of sulfuric acid and acetic acid.
Although the above noted prior art processes do in fact produce chloranil, they often suffer from low yields and exist as relatively "dirty" reactions generating excessive and unwanted byproducts.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Grocery stores and other purveyors of perishable goods often use refrigerator display cases to refrigerate and display the goods. Typically, the refrigerator display cases are vertical units with open fronts that allow consumers to view the goods and to reach into the case to retrieve the goods. Such systems typically have evaporator coils at a lower portion, and air is forced over the evaporator coils to create a cooled airstream. The cooled airstream is forced along an interior wall with some of the cooled airstream being distributed at various levels and portion reaching the top from where it is directed down a front portion of the display case to create a curtain of cool air. While these systems work well, improvements are still desired.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Cement concrete is widely used in the fields of civil engineering and construction industry at present but such a concrete has faults that it has heavy weight and is brittle. In order to reduce the weight of cement concrete, it is required to introduce fine foams in cement slurry or intermixing light-weight aggregates with cement slurry but such an attempt is poor in practicability since the concrete shows large shrinkage by drying, creep, etc., as well as is inferior in strength. For overcoming these difficulties, a process is employed at present wherein cement concrete is cured under high-temperature and high-pressure saturated vapor. However, the foregoing method is yet insufficient for obtaining high-strength concrete.
As an attempt for greatly increasing the physical or mechanical strength of light-weight concrete, polymer-impregnated concrete is proposed. Such a concrete is prepared by impregnating a light-weight concrete base material with a vinyl monomer and polymerizing the vinyl monomer by the irradiation of radiation or by impregnating a light-weight concrete base material with a vinyl monomer having previously mixed with a polymerization initiator and polymerizing the vinyl monomer by heating. The physical strength of the polymer-impregnated concrete obtained by the foregoing process is greatly improved as compared to the base material as well as the elastic property, chemical resistance, freezing and melting resistance, etc., of the concrete are also improved. However, polymer-impregnated concrete has various problems in productivity. That is, there are such problems that firstly, for effectively improving the strength of the polymer-impregnated concrete, it is required to previously dry the impregnated base material so that the water content thereof becomes lower than 0.5%, secondly, radiation must be treated in one process or a polymerization by heating in another process is accompanied by a large loss of vinyl monomer and is hence uneconomical, thirdly, the working step is complicated, etc. These problems result in increasing the product cost of polymer-impregnated concrete to prevent the practical use of polymer-impregnated concrete.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention relates to an air-conditioner, an outdoor unit and a refrigeration unit using vapor compression refrigeration cycle, and in particularly, is preferable to those which enable a motor installed in a compressor to be driven by commercially available power source and, by which a wide range from low cost products till high cost products and commonness are progressed and kind expansion is facilitated.
As refrigerant compressors used in air conditioners, outdoor units and refrigeration units using vapor compression refrigeration cycle, a constant speed type compressor which is driven at a substantially constant speed, an inverter type compressor whose rotational speed is controlled have been used, and induction motors incorporating cage type conductors (windings) are often employed since they can be easily driven by an A.C. voltage of a commercial frequency and so forth. Further, it has been known that D.C. motors are often employed having a rotor formed by providing permanent magnets to a rotor core and a rotor formed by providing three-phase windings to a rotor core from a view point of high efficiency, as disclosed in JP-A-5-211796.
Further, as motors for industry, an embedded magnet synchronous motor which can be driven by a commercially available electric power has been proposed, in view of the need of energy saving, and it is disclosed in "The Super Economotor and its Applications" by Hirano et al, in Yasukawa Technical Bulletin Vol. 62 NO. 4, 1998, Series Volume No. 241.
In the above-mentioned prior art, the motor disclosed in JP-A-5-211796 is advantageous in view of its high efficiency, but in order to start the motor, it is indispensable to use an inverter, as a power source, whose frequency is variable. A power source circuit or the like becomes complicated, and in the case of a system having a refrigeration cycle, it becomes excessively complicated in a certain application, so as to be expensive.
Further, in order to use the embedded magnet synchronous motor of the above-mentioned prior art, in an air conditioner, an outdoor unit and a refrigeration unit in which refrigeration cycle is used, consideration should be taken to the discharge volume of refrigerant necessary for the refrigeration cycle and the efficiency of the refrigeration cycle also with respect to the rotational speed of the motor, for example, and further, it must avoid that the volume of a compression chamber of the compressor, the size of the overall compressor and the size of the outdoor unit in which the compressor is installed become large.
Further, upon starting the refrigeration cycle, if the differential pressure between the suction side and the discharge side of the compressor is large, there is a possiblity that the start becomes impossible even when the embedded magnet synchronous motor is used or its reliability becomes insufficient.
Further, if overload occurs during steady-state operation of the refrigeration cycle, that is, operation in synchronized condition, a rotor in the embedded magnet synchronous motor greatly stalls, or the temperature of the windings of the motor increases. In the worst case, the material of the windings would be deteriorated or the insulation of the windings would be broken, so that the reliability of the device would remarkably be deteriorated.
In addition, it is required to minimize the affection of the permanent magnets in the embedded magnet synchronous motor to deterioration of the refrigerant and lubrication oil circulating through the refrigeration cycle.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The field of network security has become increasingly important in today's society. The Internet has enabled interconnection of different computer networks all over the world. In particular, the Internet provides a medium for exchanging data between different users connected to different computer networks via various types of client devices. While the use of the Internet has transformed business and personal communications, it has also been used as a vehicle for malicious operators to gain unauthorized access to computers and computer networks and for intentional or inadvertent disclosure of sensitive information.
Malicious software (“malware”) that infects a host computer may be able to perform any number of malicious actions, such as stealing sensitive information from a business or individual associated with the host computer, propagating to other host computers, and/or assisting with distributed denial of service attacks, sending out spam or malicious emails from the host computer, etc. Hence, significant administrative challenges remain for protecting computers and computer networks from malicious and inadvertent exploitation by malicious software.
The FIGURES of the drawings are not necessarily drawn to scale, as their dimensions can be varied considerably without departing from the scope of the present disclosure.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to an image forming apparatus, an image forming system, and a method of producing a printed product.
2. Description of the Related Art
Technologies have so far been known that allow higher quality printing results to be obtained by performing pretreatment on a sheet to be printed immediately before printing in an image forming apparatus. For example, plasma treatment can be performed as the pretreatment on a surface of the sheet. An image forming system that performs the pretreatment includes, for example, a pretreatment apparatus and an image forming apparatus; a sheet fed from a sheet feeding unit is fed to the pretreatment apparatus and is pretreated, and the sheet output from the pretreatment apparatus after the pretreatment is completed is fed to the image forming apparatus.
The sheet to be printed is often provided as a cut sheet that is cut in advance in a predetermined size, such as A4 size or B5 size, or as continuous sheet. One of type of a continuous sheet that has a roll form among types of the continuous sheet is specially called a rolled sheet.
The pretreatment apparatus and the image forming apparatus often differ from each other in conveying speed and conveying timing of the sheet. Hence, technologies have already been known that allow the difference in conveying speed and conveying timing of the sheet to be absorbed by providing a sheet buffer area that temporarily stores the sheet between the pretreatment apparatus and the image forming apparatus. When the rolled sheet is used as the sheet to be printed, the sheet buffer area temporarily stores the sheet, for example, by bending the sheet so as to absorb the difference between the conveying speeds in the pretreatment apparatus and the image forming apparatus.
Japanese Patent Application Laid-open No. 2012-081608 discloses a printer that includes a corona treatment apparatus that performs surface treatment on a printing medium, an inkjet printer that performs printing on the printing medium with the surface treated by the corona treatment apparatus, and a buffer unit that is provided between the corona treatment apparatus and the inkjet printer and temporarily stores the printing medium by bending it.
In the configuration in which the sheet after being pretreated is bent in the sheet buffer area and conveyed to the image forming apparatus, the pretreated sheet can be stopped being conveyed while being stored in the sheet buffer area due to, for example, turning off of the power supply of the apparatus. In this case, the sheet pretreated and stored in the sheet buffer area is left in the sheet buffer area without being fed to the image forming apparatus until the next printing operation is started.
The effect of the surface treatment by the pretreatment onto the sheet decreases with time. The decrease of the surface treatment effect causes a problem that, when the sheet left in the sheet buffer area is fed to the image forming apparatus and an image is formed on the sheet, the quality of the printed image is degraded.
In view of the above, there is a need to obtain an appropriate effect of the surface treatment in the configuration including the sheet buffer after the surface treatment and before the image formation onto the sheet.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
A. Field of Invention
The present invention relates to light sources which exhibit lumen depreciation over their operating lives and, in particular, to methods, apparatus, and systems for operating such light sources to compensate, at least partially, for such lumen depreciation. In general, the present invention provides a simple approach for providing constant, or near constant light output from a light source throughout its defined useful life.
B. Problems in the Art
Most high intensity discharge (HID) lamps exhibit what is called lamp lumen depreciation (LLD) characteristic. HID lamps include, but are not limited to, fluorescent, sodium (HPS), metal halide (MH), mercury vapor (HgV), and low pressure sodium (LPS). Each of these specifically mentioned types of HID lamps require a ballast transformer that regulates the operating and starting voltage at the lamp.
One definition of lumen depreciation or LLD is the gradual decline in a source's light output over operation time. Light output from the light source does not stay constant if operated at rated operating wattage. Due to several factors, primarily blackening of the inside of the arc tube from precipitation of chemicals and erosion of electrodes, HID light output usually drops as the lamp is operated. This characteristic is well known in the art. For example, a typical 1500 W MH lamp can lose up to around 50% of its light output over a typical 3000 hour cumulative operation life. See, for example, the graph of FIG. 1. Interestingly, in some lamps (including many MH lamps), lumen depreciation occurs most rapidly during the first several hundred hours of operation (e.g. 20% light loss). The rate of depreciation slows thereafter (e.g. sometimes on the order of another 10% loss for each subsequent 1000 operating hours). But cumulatively, relative to initial light output, the lamp will lose about one-half of its light-producing capacity by end of its rated life.
Manufacturers give HID lamps a rated operating wattage (ROW). ROW is the recommended wattage to operate the lamp. Manufacturers do not recommend operation substantially over ROW, as they indicate a belief it could cause failure or, at least, reduce useful life of the lamp. They indicate operation at the ROW will provide the most efficient and long-lasting operation of the lamp.
Operation substantially under ROW is also not recommended because starting the lamp can be a problem. The arc may simply drop out without sufficient power. Also, operation too far below rated wattage can materially affect efficacy of the lamp. It can also reduce light output so much as to make use of the lamp impractical for its cost. Other possible detrimental effects on the lamp or its light output are believed possible.
For example, manufacturers' generally recommend a 1500 W MH lamp not be operated at more than 1750 W (about 15 to 20% above ROW) or less than 1000 W (about 30 to 35% below ROW).
Although LLD is different for each lamp (even lamps of the same type, ROW, and manufacturer), the characteristic is well known and is fairly predictable for the same type of lamps. LLD for a particular lamp can usually be found in the technical information available from manufacturers. Sometimes LLD is expressed in terms of a multiplier factor (lumen depreciation factor or LDF) that can be used in illumination calculations to predict reduction in the light output of a lamp over a period of time caused by lumen depreciation. The LDF is usually determined by dividing the maintained lamp lumens by the published initial lamp lumens, usually yielding a value of less than 1. The LDF therefore is used in the industry as an indication of how much light loss from LLD can be expected for a lamp over its operating life.
Other factors, in addition to lumen depreciation, can contribute to what is called total light loss factor for a light fixture. Some of these factors do not involve operation of the lamp itself, such as ballast factor, ambient fixture temperature, supply voltage variation, optical factor, and surface fixture depreciation. But LLD is a significant contributor to total light loss factor.
A particular example of the LLD problem can be given in the context of sports lighting. MH lamps are commonly used, usually having ROWs on the order of at least 700 or 800 watts, and more frequently 1,000 watts, 1,500 watts, or higher. Lamp ROW gives an indication of how much electrical power is needed to run them at a specified operating voltage. Light or lumen output of a lamp is a function of wattage. For example, a 1500 W MH lamp (product ordering code MI-11500/U) from Philips Lighting, a division of Philips Electronics N.V. outputs about 155,000 lumens initially and 124,000 lumens on average when operated at 1500 W. A 1000 W NTH Philips lamp (product ordering code MI-11000/U) outputs about 105,000 lumens initially and 66,000 on average lumens. Wide area, outdoor lighting systems presently tend to favor 1000 W to 1500 W lamps because of the larger light output. Lamps over 1500 W are becoming increasingly available and used.
With reference to FIG. 5, wide area outdoor lighting, such as is used in sports field lighting to illuminate outdoor sports fields, typically utilizes several sets or banks 16 of HID luminaires 14 (each including an HID lamp 10) to illuminate not only field 24, but a volume of space above the field, to make it playable for the players and watchable from spectator stands 26 for different sports. The conventional approach is to mount lighting fixtures 14 in sets 16 on tall poles 18. A common type of lighting fixture or luminaire 14 includes a relatively high wattage high intensity discharge (HID) lamp 10 mounted in an aluminum reflector 12. Electrical power 22 is supplied via conductive cables to ballasts in ballast boxes 20, which distribute electrical power to each lamp 10. Most times a light level is specified for the field. The lighting is designed to meet such light levels by the selection of a number of fixtures (based on light output from such fixtures, which is primarily dependent upon the lamp selected), the size and type of reflector, and their aiming directions to the field. These issues are well known in the art, as are a variety of methods of selection and design of lighting configurations to meet a specified light level. Recommended levels of illumination exist for visibility and safety for various size, shape, and type of sports fields. Light levels that are too low raise not only visibility issues, but also safety considerations. For example, low or uneven light levels can make it difficult for a player to see a fast moving ball.
Theoretically, there can be almost an infinite number of ways to light a field to a specified light level. For example, a thousand fixtures containing lower power lamps could be elevated on poles or other superstructures and densely packed together encircling the field. However, this is usually impractical. Not only would the cost of that many fixtures (including lamps) be high, the cost of structures to elevate them would be likewise. The cost of maintenance would also be high. And, over time, the cost of energy to operate them would be high. Since many, if not most, athletic field lighting systems are funded by the public or non-profit organizations (e.g. schools, municipal recreation departments, private recreation leagues), cost is a major factor in selecting such lighting.
Therefore, it is conventional to try to minimize the structure used to elevate fixtures and also minimize the number of fixtures for a lighting application to reduce both capital and operating costs. This has driven HID lamp manufacturers to develop more powerful lamps so that each fixture can output greater amounts of light energy to, in turn, allow less fixtures to meet a specified light level for a field. Less fixtures allows less massive elevating structures or fewer elevating structures (e.g. less poles). For example, it has been reported that capital costs for installations with 1000 W fixtures can be at least 30 percent higher over installations with 1500 W fixtures.
However, as previously discussed, MH lamps (and most HID lamps), have an initial light output at rated wattage (after an initial “break in” period), but then, over the life of an HID lamp, the lamp usually slowly loses lumen output from LLD, even if that same level of electrical power or rated wattage is supplied. The practical effect of lumen depreciation is that, by the latter part of normal operating life of the lamp, its light output is a fraction of its starting output. If used in a system which requires a specified light level or output from the light source, the light source may have to be replaced early because it alone, or in combination with other lamps of similar reduced output, may render the light level to the target unacceptable.
One way of dealing with LLD is to do nothing. Even though the LLD characteristic will most likely result in a drop in light level from the light source, in many lighting applications it is not considered worth addressing. The drop in light level over time is simply accepted, or is not deemed significant enough, functionally or economically, to act upon. With HID lamps, the initial rapid drop-off is usually no more than 10-20%. And, subsequent light loss from LLD tends to proceed at a slower rate after that rapid initial lumen depreciation period. The lumen drop-off may not even be noticeable to most observers. However, in applications where light output is specified for a light source or for the area or target to be lighted by the light source, as is the case for wide area sports lighting, lumen depreciation can be a significant problem. As stated, in sports lighting, if light levels drop too much, it can not only be more difficult for spectators to see the activity on the field, it can become dangerous for players. Thus, doing nothing to compensate for LLD is not satisfactory for such lighting applications.
A second approach to the LLD issue is to replace lamps well prior to end of predicted operating life. For example, some specifications call for all lamps to be replaced at 40% of predicted life. While this tries to deal with the light loss from LLD, replacing lamps early during expected life span adds significant cost to the lighting system, and wastes potential usefulness of some lamps.
If lumen depreciation is dealt with in sports lighting, however, the most common way is a third approach, as follows. The designs essentially engineer into the system an excess amount of light fixtures (and thus additional lamps) in anticipation of light output drop-off caused by at least the first, rapid 10-20% depreciation, so that after about 100-200 hours of operation, the light output is at about the specified level for the particular application. These designs conventionally specify that the lamps be operated at rated operating wattages. The excess fixtures, and the higher energy use, add cost to the system (capital and energy) compared to less fixtures (and less lamps), but try to compensate (at least initially) for light loss from LLD. Also, this way of dealing with LLD does not add additional types of components, and the associated cost, to the lamps, or to their luminaires or electrical circuitry. It simply adds additional conventional lamps and fixtures. Therefore, a light designer typically selects a type and number of conventional HID lamps and fixtures that cumulatively may initially exceed the lighting requirements because the designer knows that, over time, the lumen depreciation will drop the lighting level below recommended standards. However, after the initial rapid LLD period, lumen levels decrease (somewhat slowly), but will normally gradually move below the recommended light levels. This latter LLD (after the first more rapid LLD) is many times not adequately accounted for in system design, or is ignored.
Designers may use a lumen depreciation factor or LDF to help decide how much excess light to initially produce. This tries to factor in predicted LLD light loss over whole lamp life, but only uses averages. This approach still uses a number of fixtures which initially produce excess light, but later may not produce enough light. As can be appreciated, this results in added capital and energy costs initially, and added energy and maintenance costs thereafter (e.g. operating additional lamps at ROW over their entire operating lives, and having to replace more lamps over time). It also may result in a deficiency of light later. But this has been the conventional balance adopted by the state of the art.
The state of the art has, therefore, moved in the direction of developing and using higher wattage lamps, and intentionally designing in additional fixtures that produce an initial excess amount of initial light output for an application. This addresses part of the LLD issue, but not all of it. It does not address added cost (capital and operation). Therefore, there is room for improvement in the art.
There are also continuing attempts to make other improvements involving HID lighting. For example, improvements have been made in increasing the efficiency of lighting fixtures to direct more light from each lamp to the field, see, e.g., U.S. Pat. Nos. 4,725,934, 4,816,974, 4,947,303, 5,075,828, 5,134,557, 5,161,883, 5,229,681, and 5,856,721. But, the problem of light loss from lumen depreciation of HID lamps remains a problem in the art.
There are also circuits which enable selective dimming of lights. See, for example, Musco Corporation MULTI-WATT™ system and U.S. Pat. No. 4,994,718. Capacitance is added or deleted to change light output from one or more lamps. However, this provides a user the option to select, at any time, between more or less light to the target. It does not address compensation for LLD.
Special ballasts have also been developed, particularly for fluorescent lamps, to try to keep light output from a lamp uniform over its life. However, these tend to be relatively complex, require significant interfacing components or circuitry with the lighting system, and therefore are relatively expensive and impractical. They also do not address the issues of composite lighting by sets of fixtures, as exists in lighting such as sports lighting or other composite area lighting. Therefore special ballasts of the type mentioned are generally considered too expensive for use in most lighting applications.
Solid-state light sources are known for energy efficiency and long life. They are also known to exhibit LLD. Lumen depreciation of solid state light sources is also often either ignored, or compensated for by over-lighting an area such that desired lighting levels are met even as the output of the light source depreciates. These options result in either insufficient light output or wasted light and energy.
There are many different applications for solid-state lighting sources. Some do not require a specific amount of light output be maintained, thus the degradation of the light emission is not much of a concern. For example, LED lights for toys, indicator lights, backlight illumination for small displays, etc. do not require constant light output or a minimum level, except what is viewable. Many other applications do require minimum levels of light. Some examples include task lighting, large area lighting, display lighting, projection system lighting, and others. These applications have traditionally used arc type lamps, such as HID sources. Many of these arc type lamps also experience lumen degradation, as discussed herein (and in U.S. Pat. No. 7,176,635) relating to the commercially available Musco SMART LAMP®product.
Like many of the applications utilizing arc type lamp sources, systems utilizing solid-state light sources over-light an area by the predicted amount of light loss over the useful life. For solid-state light sources, the useful life is generally determined by the degree of degradation that has occurred compared to the amount of energy consumed. At some point in the life of the light source, the amount of light output is not sufficient for the application, or does not warrant the energy cost. This is the end of its useful life, even if the source is still operational. In the case of solid-state light sources, lumen output for individual light sources can be increased by increasing the drive current supplied to the light source rather than increasing the quantity of light sources used for the application. However, this method consumes extra energy and provides excess light early in the life of the light source. Thus, energy and light are wasted. Also, increased drive current to a solid-state light source can shorten the light source's effective life span, therefore the tradeoff between increased lumen output and decreased life span must be carefully managed. Examples of solid-state light sources include light emitting diodes (LEDs), organic light emitting diodes (OLEDs), solid-state lasers, or any other semi-conductor based light source.
For LED light sources, issued U.S. Pat. No. 7,132,805 discusses a controller to drive the LED source and provide constant light output. However, this approach is complex and adds considerable cost in equipment and energy to the system.
Therefore, there is room for improvement using a low cost, simpler approach that is effective in providing constant, or near constant, light output.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
As the connections between healthy teeth and gums, and general overall health, have become increasingly evident in the past 100 years, oral care has become an important part of people's daily health maintenance regimens. In the process, a healthy looking smile has become representative of one's level of personal grooming and even social status, with straight, white and well shaped teeth being promoted in advertising and by cosmetic dentists as an integral part of one's self-image. Over the past 20 years, the availability of tooth whitening products and services has exploded in the marketplace, ranging from low-priced over-the-counter (OTC) self-applied trays, strips, pens, mouthwashes and toothpastes, to expensive professionally applied or monitored products and procedures capable of effectively whitening teeth in as little as 45 minutes. In general, professionally applied products and services administered to a patient in a dental office or other clinical setting are seen to achieve the best teeth whitening results in the shortest amount of time. This is primarily due to the concentration of active ingredient, usually hydrogen peroxide or a hydrogen peroxide precursor, found in professionally applied whitening compositions. Such high concentrations, typically above 15% hydrogen peroxide by weight and often as high as 50% hydrogen peroxide by weight, can only be safely administered in a controlled setting where a professionally trained individual can isolate soft tissues from contact with these highly oxidative compositions. Frequent monitoring of a patient's progress over, for instance, a one-hour period is also critical in maintaining a high degree of safety when working with such high hydrogen peroxide concentrations. Optionally, light or heat energy may be applied in conjunction with these strong oxidizing compositions, in order to accelerate the process beyond that which is possible using just the compositions on their own. In general, these professionally-monitored products and services applied in a dental office or clinic will be referred to collectively as in-office or chairside whitening procedures.
Chairside whitening procedures are generally performed during a dental appointment scheduled specifically for the purpose of whitening the patient's teeth, or as an adjunct following a professional teeth cleaning, formally known as a dental prophylaxis or “prophy”. When tooth whitening is conducted immediately following a prophy, the total amount of time that the patient must remain in a dental chair can often exceed two hours.
A professional tooth cleaning is recommended by the American Dental Association as a means to prevent gum disease. Gum disease, or periodontitis, is the primary cause of tooth loss in adults over the age of 40. Gum disease has also been linked to other health problems, such as heart disease, osteoporosis, respiratory diseases, and other more serious systemic diseases. According to the Center for Disease Control and Prevention, approximately 68% of adults in the United States have at least one professional tooth cleaning annually (2008). There is speculation as to the reasons why so many adults neglect the benefits obtainable from regular tooth cleanings, ranging from lack of health insurance to the fear of dental procedures. Lack of patient knowledge is a problem that can be managed, however studies have shown that better education of patients only leads to modest changes in behavior and attitudes towards preventative dentistry.
In general, a typical teeth cleaning dental appointment comprises the following procedural steps: (1) A dental hygienist or dental assistant may or may not take x-rays of a patient's teeth. (2) The dental hygienist or dental assistant will generally take between 15 and 60 minutes to work on the teeth and gums (the exact time depending upon both the amount of accumulation present, as well as the teeth cleaning method chosen), using a variety of tools, including manual or ultrasonic scalers to remove the tartar and plaque from the patient's teeth. (3) The hygienist will then floss between the teeth and generally complete the cleaning procedure by polishing the front (buccal) and back (lingual) surfaces of the teeth with an abrasive composition known as a prophylaxis (“prophy”) paste. Tooth polishing leaves a smooth tooth surface that is more resistant to the adhesion and buildup of dental plaque between dental cleaning appointments.
Despite the apparent benefits of preventative teeth cleaning as described above, nearly 80% of the population has some form of gum disease ranging from early stage gingivitis to advanced periodontitis. Symptoms of gum disease may include one or more of the following: bleeding gums, halitosis (bad breath), bad taste in the mouth, tooth sensitivity, sore gums, loose adult teeth, abscessed teeth or gums pulling away from the teeth, changes in the way the teeth fit together or dentures fitting poorly, exudates between the gums and teeth, sores in the mouth, and actual tooth loss. Such a high rate of chronic or acute gum disease indicates a low level of compliance when it comes to scheduling of a regular dental cleaning, and any means of increasing such compliance would clearly be beneficial to the patient's general oral health.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Aluminum magnesium titanate is a homogeneous solid solution formed over the entire compositional range of aluminum titanate and magnesium titanate. A sintered product of aluminum magnesium titanate has high heat resistance, a small thermal expansion coefficient, and excellent corrosion resistance. The melting point of aluminum magnesium titanate is about 1,640° C. e.g. in the case of a sintered product wherein aluminum titanate and magnesium titanate are solid-solubilized in an approximately equivalent molar ratio. This temperature is lower when compared with the melting point of aluminum titanate of 1,870° C., but it is higher when compared with the melting point of magnesium titanate of 1,600° C. Therefore, in general, the upper limit of heat resistance of aluminum magnesium titanate is inferior to that of aluminum titanate, but it is still superior in comparison with that of magnesium titanate.
On the other hand, an aluminum titanate sintered product and a magnesium titanate sintered product are, respectively, constructed from crystal grains having the pseudobrookite type crystal structure, and their coefficients of thermal expansion are anisotropic. Therefore, when heating and cooling are carried out, slippage by a thermal stress is likely to take place at the crystalline interface, and there is a drawback such that the mechanical strength tends to deteriorate due to progress in micro cracks and apertures. Since aluminum magnesium titanate also has the same drawback, the aluminum magnesium titanate sintered product is also insufficient in mechanical strength. Specifically, in a case where the aluminum magnesium titanate sintered product is used in an application in which high temperatures and heavy loads are applied, it cannot exhibit sufficient durability.
Further, the lower limit of the temperature for synthesizing aluminum titanate is 1,280° C., while the lower limit of the temperature for synthesizing magnesium titanate is 900° C. Both are unstable in the temperature range lower than the temperatures for their syntheses. As a solid solution of these compounds, aluminum magnesium titanate is also unstable at a temperature lower than the temperature range for its synthesis like aluminum titanate and magnesium titanate. Accordingly, if aluminum magnesium titanate is used in a decomposing temperature range for long time, it is likely to undergo thermal decomposition to form TiO2 (rutile) and MgAl2O4 (spinel). Here, the decomposing temperature range for aluminum magnesium titanate varies depending on a solid solution ratio of aluminum titanate and magnesium titanate, but it is usually from about 800 to 1,280° C. For example, in the case of an aluminum magnesium titanate sintered product, in which aluminum titanate and magnesium titanate are solid-solubilized in an approximately equivalent molar ratio, the aluminum magnesium titanate sintered product thermally decomposes into TiO2 (rutile) and MgAl2O4 (spinel) (Non-Patent Document 1) if it is continuously used at a temperature in the vicinity of 1,100° C. for long time.
Therefore, a conventional aluminum magnesium titanate sintered product could not be used continuously in such a decomposing temperature range, and regardless of its high heat resistance, extremely small thermal expansion coefficient and excellent corrosion resistance, the use of the conventional aluminum magnesium titanate was limited, because it had low reliability due to problems in the thermal decomposition property and mechanical strength. Non-Patent Document 1: Journal of American Ceramic Society, 1998, 81 [10], pp. 2645-2653
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Phase lock loops utilize a phase detector for comparing the phase of a reference clock with that of an output clock that utilizes a voltage controlled oscillator (VCO) to generate a phase error that varies the control voltage on the input to the VCO. By adjusting this voltage, the phase of the VCO can be locked the phase of the reference clock. Typically, some type of loop filter is disposed between the phase detector and the VCO. In a charge pump PLL, a typical phase detector generates control voltages for controlling a charge pump circuit which is operable to selectively pump charge to a node for increasing a voltage level or pulling charge from the node to provide a decreasing voltage level. To increase the voltage level, charge is sourced from a supply voltage and, to decrease the voltage level, charge is sinked to a ground reference. When the relative phase between the VCO and the reference clock are either lagging or leading, then either the sourcing or sinking of a charge pump is controlled.
This charge pump is typically facilitated with two current sources that are switched to the voltage input to the VCO. When charge is being sourced to the node, the phase of the VCO will change from either a lagging or leading to a leading or lagging phase, such that the phase detector will then cause the charge pump to sink current. When the PLL is locked, the phase error should be substantially at a zero phase error which should result in no current being sourced to or sinked from the voltage control input of the VCO. However, conventional charge pumps are fabricated with two transistor switches, one for sourcing current and one for sinking current, that are switched to either a conducting state or a non-conducting state. However, the current source is a function of the voltage on the VCO input. As the voltage changes, the characteristics of the switch and the associated current source will also change. Therefore, if the voltage changes, i.e., it is not constant, there is a possibility that the currents will not be balanced. If they are not balanced, then a phase error can result at phase lock, which could cause jitter in the clock. Thus, it is desirable that the currents are balanced for all possible voltages input to the VCO over the entire range required during the operation thereof.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
This invention relates to power control in radio communications systems such as CDMA cellular telephone systems.
xe2x80x98Outer loopxe2x80x99 power control is required in a CDMA system to set an appropriate target for the xe2x80x98inner loopxe2x80x99 power control loop which is just high enough to achieve the desired quality of service (QoS). This target point value will vary as a function of channel propagation (e.g., dispersiveness or user speed). Without effective power control, users perceived QoS will be severely degraded or network capacity will degrade (as a result of excess power transmission when exceeding desired QoS).
In particular, dynamic outer-loop power control is required in a CDMA system in order to adjust the Eb/No (the ratio of energy per bit to noise power spectral density) target point for an inner power control loop in order to track changes in channel propagation in an attempt to maintain constant QoS.
Future generations of cellular telephone services such as the proposed Universal Mobile Telephone System (UMTS) will offer a plethora of different services, each with quite different QoS requirements in terms of delay, bit error rate (BER) and frame erasure rate (FER). This represents a challenge to mobile radio equipment manufacturers who must therefore design their products to be fully adaptable to these various requirements.
Traditional methods for performing outer-loop power control, such as those based on the xe2x80x98sawtoothxe2x80x99 algorithm employed in existing CDMA networks (e.g., the IS-95 cellular standard), are not appropriate for all service types. This is especially true of low FER or high delay services (e.g., video)xe2x80x94which are to be deployed in next generation networks across the world.
In accordance with a first aspect of the present invention there is provided an apparatus as claimed in claim 1.
In accordance with a second aspect of the present invention there is provided a method as claimed in claim 6.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
This invention relates to a process for preparing polypropylene-based film for shrink packaging which possesses excellent heat shrinkability including shrinkability at low temperatures, which can be used for shrink packaging within a wide range of shrink packaging temperatures, and in which the film remains tight and free from looseness for a long period of time after shrink packaging.
2. Description of the Prior Art
It is well known in the art that a variety of thermoplastic resins can have imparted thereto the property of heat shrinkability when the resins are formed into films under molten conditions, cooled, and stretched under heating conditions.
The heat shrinkability of thermoplastic resin films has been widely utilized in so-called "shrink packaging" wherein an article is loosely packed in a stretched film, followed by heating to shrink the film into close contact with the article, thus decreasing the package volume and improving the saleability of the article.
Various kinds of films of the above-mentioned type have been put on the market, including those made of polypropylene, polyethylene, polyvinyl chloride and the like. Of these, polypropylene film has been recently widely employed for the above purpose owing to its excellent inherent properties such as transparency, gloss, moisture-proof property, non-toxicity, etc. However, known polypropylene-based films for shrink packaging have several disadvantages, including: they do not undergo significant heat shrinkage until they are heated to a high temperature; they possess a very narrow temperature range suitable for effecting shrink packaging; and their percentage of shrinkage is greatly changed by even a slight change in the shrinking temperature.
Accordingly, it is essential in the shrink-packaging step to exactly control and maintain the hot air temperature in the shrinking tunnel at a high and uniform level. When the hot air temperature is too low, the film becomes creased and rumpled due to insufficient shrinkage thereof. On the other hand, if the temperature is too high, the film will be melted and become broken. In addition, non-uniformity of the hot air temperature in the shrinking tunnel will disadvantageously produce pock-marked shrinkage irregularities owing to differences in the degree of shrinkage, thus impairing the appearance of the packaged article. Further, a conventional polypropylene-based film for shrink packaging also has the important disadvantage that even if the article is closely and tightly contacted by the packaging film immediately after the shrink packaging treatment, the film will naturally elongate and loosen with the passage of time, thus reducing the tightness and attractive appearance of the shrink-packaged article.
In order to overcome the disadvantages of known polypropylene-based films for shrink packaging, Japanese Patent Publication Nos. 43-26114 and 45-23437 describe methods for preparing films with excellent heat shrinkability by biaxially stretching films of ethylene-propylene copolymers containing a major proportion of propylene. Further, Japanese Patent Publication No. 43-26115 describes a method for preparing shrink-packaging film in which a mixture of (a) a major proportion of polypropylene and (b) a minor proportion of an ethylene-propylene copolymer containing a major proportion of ethylene, is used as the film-forming material and the film is biaxially stretched whereby once the film is shrunk, it does not stretch and loosen, such as would otherwise occur with the passage of time after completion of the shrink packaging.
However, these methods still present some problems under the existing conditions in which the time period for passing the packaged article through a shrinking tunnel is made very short in order to speed up the shrink packaging step and, hence, the shrink packaging is effected by instantaneously blowing hot air on the shrinkable film. Accordingly, there is a strong demand for the development of a polypropylene-based film for shrink packaging which has an excellent shrinkability at low temperatures and which does not stretch and become loose after completion of the shrink packaging.
It is, therefore, an object of the present invention to provide a process for preparing a polypropylene-based film for shrink packaging which overcomes the above-mentioned disadvantages of the prior art.
It is another object of the present invention to provide a process for preparing a polypropylene-based film for shrink packaging which has excellent low temperature shrinkability.
It is a further object of the present invention to provide a process for preparing a polypropylene-based film for shrink packaging which has a high degree of heat shrinkability over a wide range of shrink-packaging temperatures.
It is a still further object of the present invention to provide a process for preparing a polypropylene-based film for shrink packaging by which uniform and satisfactory shrink packaging is feasible at high speed without exactly controlling the temperatures of the hot air in the shrinking tunnel.
It is an additional object of the present invention to provide a method for preparing a polypropylene-based film for shrink packaging in which the shrunk film does not elongate or loosen after completion of the shrink packaging.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Radio Frequency IDentification (RFID) systems typically include RFID tags and RFID readers. RFID readers are also known as RFID reader/writers or RFID interrogators. RFID systems can be used in many ways for locating and identifying objects to which the tags are attached. RFID systems are particularly useful in product-related and service-related industries for tracking objects being processed, inventoried, or handled. In such cases, an RFID tag is usually attached to an individual item, or to its package.
In principle, RFID techniques entail using an RFID reader to interrogate one or more RFID tags. The reader transmitting a Radio Frequency (RF) wave performs the interrogation. The RF wave is typically electromagnetic, at least in the far field. The RF wave can also be predominantly electric or magnetic in the near field. The RF wave may encode one or more commands that instruct the tags to perform one or more actions.
A tag that senses the interrogating RF wave responds by transmitting back another RF wave. The tag generates the transmitted back RF wave either originally, or by reflecting back a portion of the interrogating RF wave in a process known as backscatter. Backscatter may take place in a number of ways.
The reflected-back RF wave may further encode data stored internally in the tag, such as a number. The response is demodulated and decoded by the reader, which thereby identifies, counts, or otherwise interacts with the associated item. The decoded data can denote a serial number, a price, a date, a destination, other attribute(s), any combination of attributes, and so on. Accordingly, when a reader reads a tag code, data can be learned about the associated item that hosts the tag, and/or about the tag itself.
An RFID tag typically includes an antenna system, a radio section, a power management section, and frequently a logical section, a memory, or both. In earlier RFID tags, the power management section included an energy storage device, such as a battery. RFID tags with an energy storage device are known as active or semi-active tags. Advances in semiconductor technology have miniaturized the electronics so much that an RFID tag can be powered solely by the RF signal it receives. Such RFID tags do not include an energy storage device, and are called passive tags.
A challenge with RFID systems is the possibility of a rogue RFID reader. Rogue RFID readers may be used to surreptitiously alter tag data from their intended legitimate value, or to surreptitiously alter the tag itself such as by electronically killing or deactivating some or all of the tag's features. The threat exists in many contexts. In a purely commercial context, the loss may be financial. In other contexts, where food or pharmaceuticals are tagged, the loss may be of a different nature.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Technical Field
The present invention relates to a manufacturing method of a semiconductor device for processing a substrate having a high dielectric gate insulating film and a metal electrode, and a substrate processing apparatus.
2. Description of Related Art
In recent years, with high integration and high speed of a semiconductor device, a finer transistor and a thinner film are being developed. When the thinner film of a gate insulating film is progressed by this finer transistor, leak current of the gate electrode due to tunnel current, etc, is increased in a silicon oxide film (SiO2 film) that has been used heretofore as the gate insulating film. Particularly, the gate insulating film does not function as an insulating film when the leak current is increased, unlike a capacitor insulating film, and therefore the leak current must be suppressed. Also, in the gate electrode, it is necessary to make electricity resistance small, increase conductivity, and accelerate operation characteristics. Therefore, study on the semiconductor device, with the gate insulating film made of a high dielectric material and the gate electrode made of metal, is being pursued. The gate insulating film made of a high dielectric material is called a high dielectric also called High-k gate insulating film, and the gate electrode made of metal is called a metal electrode hereinafter.
FIG. 9 shows main steps and typical processing contents of a process flow of a MOS transistor. In order to manufacture the MOS transistor, first, the gate insulating film is formed using the high dielectric material such as HfO and HfSiO on a silicon substrate (gate insulating film forming step).
Next, the gate electrode is formed using a metal material such as tungsten(W), ruthenium(Ru), titanium nitride(TiN), tantalum(Ta), molybdenum(Mo) instead of conventional polysilicon (gate electrode forming step).
Subsequently, processing of the gate electrode and the gate insulating film is performed by dry etching, through formation and processing of an etching mask (etching step). Thereafter, an etching damage of the gate electrode, namely, a physical roughness of a processing surface generated by etching is restored by thermal oxidation (restoration step of the gate electrode). When the restoration step is ended, ion implantation is performed to the surface of the silicon substrate, to thereby form source and drain. Subsequently, dopant (phosphorus (P), arsenic (As), and boron (B), etc, implanted to channel, source, and drain) is activated by annealing.
However, when the gate electrode is made of metal, the gate electrode is excessively oxidized in the restoration step of the gate electrode, and a resistance value is increased in some cases by oxidation.
As a method of suppressing excessive oxidation of the gate electrode, a method of reducing oxidation of the gate electrode by using hydrogen as a reducing agent, in a processing pressure of mixed gas of oxygen gas and hydrogen gas, with a temperature of the silicon substrate set to be a prescribed temperature of 850° C. or more, can be considered.
However, high dielectric materials such as hafnium (HfO), hafnium silicate (HfSiOx, also called HfSiO hereunder), hafnium nitride silicate (HfSiON), and aluminum oxide (AlOx) are sometimes crystallized, for example, by a thermal history of about 400° C. to 1000° C. Accordingly, when the silicon substrate is heated as described above to 850° C. or more, a High-k gate insulating film made of high dielectric material is sometimes formed into a polycrystal structure. A crystal grain boundary exists in the High-k gate insulating film having polycrystal structure, and therefore current flows through defects of the crystal grain boundary when a voltage is applied to the gate electrode, resulting in an increase of leak current.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
This invention generally relates to alignment of optical elements and in particular to alignment of a fiber optic with active or passive optical components.
2. Description of the Related Art
The telecommunications network serving the United States and the rest of the world is presently evolving from analog to digital transmission with ever increasing bandwidth requirements. Fiber optic cable has proved to be a valuable tool, replacing copper cable in nearly every application from large trunks to subscriber distribution plants. Fiber optic cable is capable of carrying much more information than copper with lower attenuation.
In a typical optical fiber, separate subscriber/data sessions are handled concurrently on a single optic fiber by means of modulation of each of those subscriber data streams on different portions of the light spectrum by what is known as xe2x80x9cwavelength division multiplexingxe2x80x9d (WDM). Current implementations of WDM involve as many as 128 semiconductor lasers each lasing at a specific center frequency within the range of 1525-1575 nm. Each subscriber DataStream is optically modulated onto the output beam of a corresponding semiconductor laser. The modulated information from each of the semiconductor lasers is combined onto a single optic fiber for transmission. As this digital signal is passed across an optical network, it will be subject at various intervals to amplification by, for example, Erbium doped amplifiers and dispersion compensation by, for example, optical circulators with coupled Bragg filters. At each node in the network, e.g. central office or remote terminal, optical transceivers mounted on fiber line cards are provided. On the transmit side, a framer permits SONET framing, pointer generation and scrambling for transmission of data from a bank of lasers and associated drivers, with each laser radiating at a different wavelength. On the receive side, the incoming signals are separated into channels detected by photo detectors, framed and decoded.
Throughout the network a broad range of active optical components such as lasers and photo detectors and passive optical components such as circulators and isolators and filters are utilized to process optical beams from individual optical fibers. Each junction between an optical fiber and these active and passive optical components requires extremely precise alignment between the fiber and component in order to maximize coupling efficiency. Alignment tolerances on the order of 0. 1 micron or less are common.
In order to achieve these tolerances a three step fabrication process is required for each completed assembly. In the first step an elaborate clamping fixture is used to clamp fiber and component relative to one another. Then either one or both of the fiber and component are manually brought into alignment using the micrometers and angle plates which make up the typical clamping fixture. In the second step the component and fiber are fixed to one another using epoxy or some other fastening method and the fixture is removed. The removal of the frame typically results in a release of strain or tension in the bond joining the fiber and component. This produces small but significant misalignment of the assembly, which in turn results in the necessity of a third and final assembly step. In the third step the completed assembly is reclamped in a temporary fixture and the fiber or component are struck with a hammer or other more precise instrument to bring them back into alignment. The above discussed process is very time consuming and labor intensive and accounts for a major portion of the finished assemblies cost.
What is needed are improved methods which reduce the time, cost and expenses associated with the alignment of fiber optic assemblies.
The current invention provides a method and apparatus for aligning optical components including lenses, filters, lasers, fiber optics, etc. It may be used with particular advantage for the alignment of a fiber optic with active or passive optical components. It is inexpensive to fabricate. It does away with the need for expensive setup equipment. It allows optical components to be aligned with a high degree of accuracy and permanence. It has a small form factor.
In an embodiment of the invention the apparatus for aligning at least a first optic element and a second optic element includes a frame and at least one sleeve. The frame defines a frame bore along a longitudinal axis thereof. The at least one sleeve defines an eccentric bore configured to contain a respective one of the first optic element and the second optic element. The at least one sleeve is rotatably coupled with respect to the frame bore to align the first optic element with the second optic element in a plane intersected by the longitudinal axis.
In an alternate embodiment of the invention the apparatus for aligning includes a frame and at least one pair of nested sleeves. The frame defines a frame bore along a longitudinal axis thereof. The at least one pair of nested sleeves each include a corresponding eccentric bore, with an inner nested one of said pair of nested sleeves coupled to at least one of the first optic element and the second optic element and an outer one of said pair of nested sleeves rotatably coupled to said frame bore to align the first optic element with the second optic element by an epicyclic motion of the at least one of the first optic element and the second optic element.
In still another embodiment of the invention a method for aligning at least a first optic element and a second optic element, at a selected location relative to one another is disclosed. The method comprises the act of effecting an epicyclic rotation of at least a selected one of the first optic element and the second optic element to align the optic elements at the selected location.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The present invention generally related to the field of vented battery caps, and more particularly, to the field of multiple plug vented battery caps which are designed to arrest the ignition and/or to minimize the expulsion into the atmosphere. It is well known that a suitable battery vent plug must provide for the expulsion of gases which build up during the chemical charging and discharging action of the battery, while effectively preventing the leakage or evaporation of substantial quantities of the battery electrolyte. To this end, battery vent plugs are normally designed with gaseous connection means for venting the gases produced within the battery to the atmosphere, while providing electrolyte retention means within the battery vent plug for retaining and returning as much of the electrolyte to the battery as is practically feasible. This retention of battery electrolyte is normally accomplished through the use of various baffles and/or gabled floors in the battery vent plug which tend to funnel the battery electrolyte which escapes into the battery vent plug back into the battery cells.
Originally, few provisions were made apart from those described above in order to minimize the chance that a spark in the vicinity of the battery would ignite the battery gases, thereby resulting in the possible explosion of the battery vent plug away from the battery container and/or the explosion of the battery itself. More recently, however, attention has been focused upon the desirability of minimizing the chances that a spark in the vicinity of an operating battery might indeed ignite those gases upon their expulsion to the atmosphere, and attempts have been made to insure that the inadvertent ignition of those gases does not have explosive results. One approach to solving this problem has been to provide a multiple battery vent plug in which gaseous communication is provided from the center of each plug through the body of the plug to four rectangularly widely spaced pin hole-like gas outlets in the top cover of the battery for venting these explosive battery gases to the atmosphere, presumably in a diffuse manner. Alternatively, in single battery vent plugs, the interior of the plug which is directly in communication with the battery cell communicates with a gaseous passage disposed under the top surface of the plug by a slot, having a longitudinal member disposed therein, presumably to prevent battery electrolyte from entering the gaseous passage. Two spaced pin hole-like openings are provided on the upper surface of the rather broad cap, again for the purpose of diffusing the explosive battery gases into the atmosphere.
Other designs for venting battery gases safely into the atmosphere have tended to replace these pin hole-like openings with larger cylindrical or rectangular openings into which or next to which are disposed a porous ceramic diffusers. These ceramic diffusers are particularly adapted for use in multiple battery vent plugs which have a hollow body that is adapted for the mounting of such a porous diffuser in a position intermediate between two adjacent battery plugs. One such porous diffuser for a single battery vent plug is disclosed in French Pat. No. 839,808 (1939). Alternatively, another type of microporous membrane is disclosed in U.S. Pat. No. 3,507,708, and U.S. Pat. No. 3,879,227 also discloses such a porous diffuser disposed within a multiple battery vent plug. As with most battery vent plugs, the battery vent plugs described in the above mentioned patents are normally provided with sloping surfaces and/or baffles to prevent or inhibit battery electrolyte from contacting the porous diffuser and/or other vent means.
In particular, in addition to having a porous diffuser located adjacent the atmosphere, U.S. Pat. No. 3,879,227 further discloses a compartment disposed between the porous diffuser and the atmosphere, which compartment has an elongated outlet opening to the atmosphere. The ratio of the volume in cubic inches of the compartment to the area of the elongated outlet in square inches is within a particular range. Presumably, this configuration minimizes the effect of explosions which occur in the area immediately adjacent the porous diffuser, and the size of the compartment and cross sectional area of the elongated opening are selected so as to prevent explosions which occur within the compartment from having serious consequences. To this end, the exterior surface of the compartment is constructed so that upon the ignition of gases within the compartment the elongated opening has a tendency to increase in cross sectional area, thereby venting the ignited gases directly into the atmosphere. Two additional types of multiple battery vent plugs are disclosed in U.S. Pat. Nos. 3,992,226 and 4,086,395 (which is a parent of the present application). Both of these patents provide structures with at least one venting orifice therein directed away from the battery when fitted into the battery vents, and both plugs of these patents have internal configurations which help to eliminate any possibility of the battery electrolyte passing from the battery through the vent plug.
Furthermore, at least one type of vent plug is known wherein a separate top member of the plug fastens to the inside of a bottom member that fits into the battery vent openings. In that instance, prong members project upwardly form the inside of the base member and engage a rim which runs along the inside of the top member to securely fasten the two members together.
Other patents which generally show multiple battery vent plugs include U.S. Pat. Nos. 3,284,244, 3,265,538, 3,369,940 and 3,597,280. Other battery vent patents include U.S. Pat. Nos. 3,466,199, 2,670,396 and the references cited thereon.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The invention relates to a door for a household appliance, having a plate-type base part on which a movable handle is arranged. Furthermore the door comprises a coupling apparatus which is connected to the handle and by means of which the handle, as a function of the movement of the door, can be pivoted relative to the base part. Furthermore the invention also relates to a household appliance having a door of this type.
Ovens which have a door for closing a cooking compartment are known from the prior art. Doors of this type usually have a handle on the front panel, which can be gripped by a user in order to be able to pivot the door. In order also to design the accessibility of the door to be user friendly when it is in a fully open position, handles of this type can be pivoted relative to the plate-type base part, so that they can also be easily gripped in this open position of the door.
With conventional embodiments, a device which comprises two bracing cables is available for this purpose. The pivoting mechanism of the handle is embodied with a double bracing cable guide, wherein when flap doors cannot be retracted into the housing of the household appliance, the connection of this bracing cable guide to the door hinge and its translation is realized. In embodiments in which a door of this type, in the fully open state, is also retracted into the housing of the household appliance, the connection of the two bracing cables with a double bracing cable guide likewise takes place in the bearing top and by way of a rotatably mounted axis in the lower door region. When the door is opened, the pivoting motion of the handle is transmitted to the lower door axis.
The conventional embodiments are of a relatively complicated and component-intensive design. As a result, the assembly and the movement principle for force transmission is also relatively complex. As a result, it may also be more prone to functional errors.
A household appliance door with a single-run cable pull for a pivotable handle is also known from DE 10 2011 084 300 A1.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Vehicular emissions which are the principle pollutants that have negative effects on public health and the natural environment are generally recognised to be carbon monoxide, hydrocarbons, nitrogen oxides (NOx) and particulate matter.
Diesel engines run at a high air to fuel ratio under very fuel lean conditions. Because of this they have low levels of emissions of gas phase hydrocarbons and carbon monoxide and are instead characterised by relatively high levels of emissions of NOx and particulate matter, relative to the current and agreed future emission regulations set by intergovernmental organisations. The control of particulate matter emissions and of NOx represent significant challenges to the diesel engine manufacturer because they are coupled inversely. Modern passenger vehicles include exhaust gas recirculation. When the engine operates cooler it produces less NOx but more particulate matter and conversely at higher temperatures combustion is more complete generating less particulate matter but more NOx. Therefore changes in engine design need to be combined with effective trapping and treatment processes to limit the emissions of these harmful pollutants to the atmosphere.
Emission legislation in Europe from 1st September 2014 (Euro 6) maintains the allowable limit set in Euro 5 (which came into force in September 2009 for the approval of vehicles and applied from January 2011 for registration and sales of new types of cars) for the mass of particulate matter emitted from diesel passenger cars of 4.5 mg/km as measured by the particulate measurement programme procedure.
However, for Euro 6, all vehicles equipped with a diesel engine will be required substantially to reduce their emissions of nitrogen oxides as soon as Euro 6 enters into force. For example emissions from passenger cars will be capped at 80 mg/km which is a reduction of more than 50% as compared to the Euro 5 standards. Furthermore combined emissions of hydrocarbons and nitrogen oxides from diesel vehicles will also be reduced. For example, these will be capped at 170 mg/km for passenger cars.
Therefore, the new Euro 6 emission standard presents a number of challenging design problems for meeting diesel emission standards. In particular, how to design a filter, or an exhaust system including a filter, to reduce the NOx and combined NO and hydrocarbon emissions, yet at the same time meeting the emission standards for PM pollutants and CO all at an acceptable back pressure, e.g. as measured by maximum on-cycle backpressure on the EU drive cycle.
Ambient particulate matter is typically divided into the following categories based on their aerodynamic diameter (the aerodynamic diameter is defined as the diameter of a 1 g/cm3 density sphere of the same settling velocity in air as the measured particle):
(i) Particles of an aerodynamic diameter of less than 10 μm (PM-10);
(ii) Fine particles of diameter below 2.5 μm (PM-2.5);
(iii) Ultrafine particles of diameter below 100 nm; and
(iv) Nanoparticles of diameter below 50 nm.
Since the mid-1990s, particle size distributions of particulates exhausted from internal combustion engines have received increasing attention due to possible adverse health effects of fine and ultrafine particles. Concentrations of PM-10 particulates in ambient air are regulated by law in the USA. A new, additional ambient air quality standard for PM-2.5 was introduced in the USA in 1997 as a result of health studies that indicated a strong correlation between human mortality and the concentration of fine particles below 2.5 μm.
Interest has now moved to consider ultrafine and nanoparticles generated by diesel and gasoline engines because they are understood to penetrate more deeply into human lungs than particulates of greater size and consequently they are believed to be more harmful than larger particles. This belief is extrapolated from the findings of studies into particulates in the 2.5-10.0 μm range.
Size distributions of diesel particulates have a well-established bimodal character that correspond to the particle nucleation and agglomeration mechanisms, with the corresponding particle types referred to as the nuclei mode and the accumulation mode respectively.
In the nuclei mode, diesel particulate is composed of numerous small particles holding very little mass. Nearly all nuclei mode diesel particulates have sizes of significantly less than 1 μm, i.e. they comprise a mixture of fine, ultrafine and nanoparticles. Nuclei mode particles are believed to be composed mostly of volatile condensates (hydrocarbons, sulphuric acid, nitric acid etc.) and contain little solid material, such as ash and carbon.
Accumulation mode particles are understood to comprise solids (carbon, metallic ash etc.) intermixed with condensates and adsorbed material (heavy hydrocarbons, sulfur species, nitrogen oxide derivatives etc.) Coarse mode particles are not believed to be generated in the diesel combustion process and may be formed through mechanisms such as deposition and subsequent re-entrainment of particulate material from the walls of an engine cylinder, exhaust system, or the particulate sampling system.
The composition of nucleating particles may change with engine operating conditions, environmental condition (particularly temperature and humidity), dilution and sampling system conditions. Laboratory work and theory have shown that most of the nuclei mode formation and growth occur in the low dilution ratio range. In this range, gas to particle conversion of volatile particle precursors, like heavy hydrocarbons and sulphuric acid, leads to simultaneous nucleation and growth of the nuclei mode and adsorption onto existing particles in the accumulation mode. Laboratory tests (see e.g. SAE 980525 and SAE 2001-01-0201) have shown that nuclei mode formation increases strongly with decreasing air dilution temperature but there is conflicting evidence on whether humidity has an influence.
Generally, low temperature, low dilution ratios, high humidity and long residence times favour nanoparticles formation and growth. Studies have shown that nanoparticles consist mainly of volatile material like heavy hydrocarbons and sulphuric acid with evidence of solid fraction only at very high loads.
Particulate collection of diesel particulates in a diesel particulate filter is based on the principle of separating gas-borne particulates from the gas phase using a porous barrier. Diesel particulate filters can be defined as deep-bed filters and/or surface-type filters. In deep-bed filters, the mean pore size of filter media is bigger than the mean diameter of collected particles. The particles are deposited on the media through a combination of depth filtration mechanisms, including diffusional deposition (Brownian motion), inertial deposition (impaction) and flow-line interception (Brownian motion or inertia).
In surface-type filters, the pore diameter of the filter media is less than the diameter of the particulate matter, so particulate matter is separated by sieving. Separation is done by a build-up of collected diesel particulate matter itself, which build-up is commonly referred to as “filtration cake” and the process as “cake filtration”.
It is understood that diesel particulate filters, such as ceramic wallflow monoliths, may work through a combination of depth and surface filtration: a filtration cake develops at higher soot loads when the depth filtration capacity is saturated and a particulate layer starts covering the filtration surface. Depth filtration is characterized by somewhat lower filtration efficiency and lower pressure drop than the cake filtration.
Diesel particulate filters have been shown to be extremely effective at removal of particulate matter over the entire particle size range. However these filters have limited capacity for trapping particulate matter before the pressure-drop becomes excessive therefore it is necessary periodically to regenerate the diesel particulate filter. Passive regeneration does not readily take place as combustion of the retained particulate matter in the presence of oxygen requires higher temperatures than those typically provided by diesel engine exhaust. One effective method to lower the combustion temperature of the trapped particulate matter on the diesel particulate filter is addition of a catalysed washcoat to the filter wall. Compositions of catalysed washcoats used are similar to those used in diesel oxidation catalysts and typically comprise at least one platinum group metal. The reactions on the catalysed diesel particulate filter include oxidation of CO and HC and oxidation of NO to NO2 which enables combustion of the particulate matter at a much lower temperature than in the presence of oxygen.
U.S. Pat. No. 7,722,829 discloses a catalysed soot filter which simultaneously treats the CO and HC gaseous components and the particulate matter in diesel exhaust gas. The diesel particulate filter is a wall flow substrate which is coated in a washcoat comprising a platinum group metal. The washcoat is coated on to part of the internal walls of both the inlet and outlet passages of the substrate such that more than 50% of the platinum group metal components are present on the walls of the inlet passages. US '829 discloses that the positioning of the majority of the platinum group metal components upstream was found to improve the efficiency of the platinum group usage and allow the substrate to maintain its catalytic function even after multiple regeneration cycles. Furthermore it discloses that this positioning was also found to favour the combustion of soot and regeneration of the filter with the following reasoning. The high concentrations of platinum group metals in the upstream zone of the substrate generated increased concentrations of NO2 in the upstream zone (by oxidation of NO present in the diesel engine emissions) which could flow towards the outlet passages to combust soot deposited in the downstream zone where most of the soot was collected. US '829 discloses that the coatings may be disposed as a thin coating on the surface of the internal walls of the wall flow substrate and/or may permeate the porous walls to some extent.
A variety of technologies have been explored to reduce NOx emitted from diesel exhaust systems to environmentally acceptable nitrogen for release to the atmosphere. Selective NOx reduction (lean NOx catalyst) using the on-board diesel fuel or a derivative to selectively catalyse the oxidation of HC and NOx to CO2, H2O and N2 was extensively investigated and two main candidate materials identified as selective catalysts. However it has been reported in the literature that it is thought that this system will not be sufficient to meet the stringent requirements of Euro 6.
Lean NOx traps (NOx adsorber catalyst) use a basic metal oxide to adsorb NOx during the lean mode of operation. Exhaust gas rich in NO is converted to NO2 over a platinum group metal-containing catalyst and the NO2 is trapped and stored on e.g. an alkaline metal oxide which is incorporated within the platinum group metal-containing catalyst. The NO2 is then desorbed under rich conditions and reduced using rhodium which is also incorporated on the catalyst.
SCR involves use of ammonia in the presence of a suitable catalyst, which ammonia acts as a selective reductant for NOx. Typically urea is the source of the ammonia, which hydrolyses in the exhaust system at about 200° C. Suitable catalysts include metal exchanged zeolites and mixed catalysts of vanadium and titanium dioxides. The technology is potentially capable of NOx reduction of greater than 90% so it is seen as a good candidate for meeting the new stringent NOx requirements for diesel engines. However the SCR is prone to contamination from HC, CO and particulates which reduces its effectiveness. Furthermore, for many diesel engines, a majority of NOx emitted from the exhaust system is in the form of NO, whereas a faster SCR reaction proceeds from a mixture of NO and NO2. NO2 is a more reactive compound than NO and the faster SCR reaction can extend the operating temperature of the SCR process to lower temperatures.
WO 02/14657 discloses an aftertreatment system for lean burn diesel applications configured with a catalysed soot filter upstream of a zeolite SCR to produce substantially better NOx conversion performance than the SCR catalyst alone. The catalysed soot filter is coated on the internal walls of the filter substrate with the catalyst being applied by solution impregnation. This application technique suggests that the catalyst is substantially present within the pores of the internal walls of the substrate to minimise increase in exhaust gas back pressure caused by the catalyst as far as possible. The catalyst is coated along the full length of both the inlet channel internal walls and the outlet channel internal walls of the filter substrate. It is mentioned at page 31, lines 28-29 that it may be possible selectively to coat portions of the channels but no further exemplification is provided.
We have now designed a new catalysed soot filter for treatment of diesel engine exhaust emissions which removes PM, HC and CO from the exhaust emissions and simultaneously enriches NO2 concentration in NOx emitted from a diesel engine to enable more efficient treatment of NOx, for example using a SCR catalyst. The catalysed soot filter is designed such that the catalyst is substantially coated on, not in, the internal walls of the filter substrate, with different axial coating lengths on the inlet channels and outlet channels, which arrangement has been found to maintain an acceptable exhaust gas back pressure with respect to coating loading and soot trapping and regeneration and has also been found to provide enhanced NO2 enrichment as compared to filters with coatings substantially or partially “in-wall”.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
This relates generally to imaging devices, and more particularly, to imaging devices with clear image pixels.
Image sensors are commonly used in electronic devices such as cellular telephones, cameras, and computers to capture images. In a typical arrangement, an electronic device is provided with an array of image pixels arranged in pixel rows and pixel columns. Circuitry is commonly coupled to each pixel column for reading out image signals from the image pixels.
Conventional imaging systems employ a single image sensor in which the visible light spectrum is sampled by red, green, and blue (RGB) image pixels arranged in a Bayer mosaic pattern. The Bayer Mosaic pattern consists of a repeating cell of two-by-two image pixels, with two green pixels diagonally opposite one another, and the other corners being red and blue. However, the Bayer pattern does not readily enable further miniaturization of image sensors via smaller image pixel sizes because of limitations of signal to noise ratio (SNR) in the image signals captured from the image pixels.
One means of improving SNR is to increase the available image signal by increasing light exposure at low light levels, where SNR limits the image quality. One conventional method is the use of subtractive filters, in which, for example, red, green, and blue image pixels are replaced by cyan, magenta, and yellow image pixels. However, these signals must generally be converted to RGB or some equivalent output image signal colors to be able to drive most conventional image displays. This transformation generally involves the modification of captured image signals using a color correction matrix (CCM), which can amplify noise, so that the effect of the exposure increase is compromised.
It would therefore be desirable to be able to provide imaging devices with improved means of capturing and processing image signals.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
In the related art, regarding an output setting screen of a computer program for controlling an output device, there is known a function of calling a set of set values for a plurality of setting items registered in advance (which is called favorites, a shortcut icon, a one-click icon, and the like). For example, a printer driver provides a user interface such as a print setting screen, and accepts various setting changes from a user. In the printer driver, there are a large number of setting items, and the number of prohibitions among the setting items is large, so that it is difficult for the user to determine the set value of the setting item. Thus, there are known printer drivers providing a setting set in which some set values of print setting items are changed.
For example, Japanese Patent Application Laid-open No. 2002-182871 (Patent Literature 1) discloses a configuration of displaying, in an icon display region, a list of one-click icons each representing one or a plurality of printing functions to easily perform setting of the printing function of the printer.
Among the various setting items, there are some setting items of which the settings can be changed a little for each time of output processing. Such setting items for the printer driver include, for example, setting items related to printing quality such as monochrome printing, toner saving, and color balance. Whether to register, as a different setting set, the settings that are changed a little for each time of output processing depends on the user. At a later date, however, demand is frequently caused for reusing the settings that has been used in the past. However, the set value of the setting item is held only during the output processing, and cannot be reused at a later date.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Internal combustion engines can produce exhaust streams that include various gases and combustion products. Some of these gases, such as nitrogen oxide gases (NOx) including, for example, nitrogen monoxide (NO) and nitrogen dioxide (NO2), can contribute to environmental pollution in the form of acid rain and other undesirable effects. As a result, many regulations have been imposed on engine manufacturers in an attempt to reduce the levels of NOx emitted into the atmosphere.
NOx removal from the exhaust streams of lean burn engines can be especially challenging. Lean burn engines, which may include diesel engines as well as certain spark ignited engines, can operate with an excess of oxygen. Specifically, in a lean burn engine, more oxygen may be supplied to the engine than is necessary to stoichiometrically consume the fuel admitted to the engine. As a result, the exhaust streams of these lean burn engines may be rich in oxygen, which can limit the available techniques suitable for NOx removal.
To reduce the NOx concentrations in the exhaust stream of lean burning engines, a number of lean-NOx catalysts have been developed that may selectively reduce NOx in oxygen rich exhaust streams with hydrocarbon reductants. These lean-NOx catalytic systems may depend on the presence of sufficient levels of hydrocarbon species to be fully effective. The amount of hydrocarbons available in the exhaust streams of many lean burning engines can be low. Therefore, in some applications including active catalytic systems, a hydrocarbon compound such as diesel fuel, for example, may be introduced into the exhaust stream in order to promote reduction of NOx compounds.
Several lean-NOx catalysts have been developed that include alumina in some form. Alumina is known as a durable material, and it has shown promise as a catalyst for lean-NOx reactions at high temperatures. Nevertheless, even alumina-based catalysts have proven problematic. For example, certain catalysts or catalytic systems that have been used with lean burn engines can suffer from low NOx conversion efficiencies, inadequate catalyst durability, low thermal stability, narrow effective temperature ranges, and NOx selectivity limited to only certain compounds.
In an attempt to address the shortcomings of lean-NOx catalysts, various catalyst configurations and compositions have been proposed. For example, U.S. Pat. No. 5,980,844 (“the '844 patent”) describes a NOx-reducing catalyst that includes silver oxide particles dispersed on alumina. While the catalyst of the '844 patent may reduce emissions of certain NOx gases, the catalyst may be costly to manufacture in view of the complex processing technique required for producing the small, widely dispersed silver oxide particles of the catalyst.
The disclosed exhaust treatment elements are intended to overcome one or more shortcomings of the prior art systems.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The invention relates to a connection of the two facing ends of a tubular bone cut by an operation or of a prosthesis part to the end of a tubular bone.
2. Description of the Prior Art
In the treatment of patients, a case can occur where, due to fracture of a bone or due to tumours or the like, a longitudinal part of a tubular bone must be removed by operation and the surgeon must then attempt to reconnect the remaining part lengths to one another and, in doing this, to retain the original bone length. This has hitherto been relatively difficult, and it was sometimes necessary to resort to splinting of the two bone parts.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The field of the present invention relates to mechanical contacts and support for printed circuit board (PCB) mountable power modules such as rectifiers, MOSFETs and IGBTs. More specifically, the present invention relates to a system and method of supporting a plurality of mechanical joints through a common mechanical support, i.e., a support which clamps the module to its thermal interface and clamps the PCB to the module.
Current PCB mountable power modules often require two separate points of mechanical contact or support. The first of these two mechanical joints involves a thermal interface of the module to secure a base plate to a heat sink or cold plate. The second of these two mechanical joints involves a solder joint of module terminals to a printed circuit board (PCB) and support of the board.
Typically the thermal interface is addressed by the use of fasteners and/or washers, which secure the base plate or substrate of a power module/device to a heat sink or cold plate. This fulfills the requirements of the first mechanical joint, but the second mechanical joint, which involves the support of the PCB, is left to the solder joint. Through applications of environmental stress like thermal stresses, where there may be a temperature mismatch of materials, or vibrational stresses, there can be enough resulting mechanical stress placed on either the solder terminal joint directly or transferred through the solder-terminal joint to the substrate-terminal joint that this electrical connection will fail. Prior approaches for modules that have features for fasteners through the board and into the shell of the module cause the loss of valuable board space by the additional holes and voltage clearance issues introduced by these additional fasteners.
Thus, there is a need for a system and method of assembly for mechanical contacts and support for PCB mounted power modules which provides the support of both mechanical joints through a common mechanical support by clamping the power module to its thermal interface and clamping the PCB to the module.
Further, there is a need for a system and method of mounting power modules on a PCB which minimizes the use of PCB space in the support of such power modules.
In addition, there is a need for a system and method of installation of mounting power modules on a PCB which uses a simplified design to reduce assembly time.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Recently, research on a wavelength division multiplexing (WDM) communication system for higher-speed and larger-capacity communications has been actively promoted. One of the key optical components used in the WDM communication system is an optical multiplexer/demultiplexer device for coupling or splitting a plurality of lights having respective wavelengths. An exemplary optical multiplexer/demultiplexer device is disclosed in Patent Publication 1 and Non-Patent Publication 1 listed later.
Referring to FIG. 16, a prior art straight-optical-waveguide type optical multiplexer/demultiplexer device shown in FIG. 1 in Patent Publication 1 will be explained. FIG. 16 is a schematic view of a straight-optical-waveguide type optical multiplexer/demultiplexer device. The straight-optical-waveguide type optical multiplexer/demultiplexer device 400 has first and second straight optical waveguides 402, 404 which intersect each other at a junction at an angle 2θ, an optical filter 406 disposed at the junction, and a third straight optical waveguide 408 disposed on a line extended along the first straight waveguide 402 and on the opposite side thereof relative to the optical filter 406. The optical filter 406 is defined by a dielectric multilayer film. Further, the optical filter 406 is positioned and oriented so that an equivalent reflection center plane 406a thereof includes an intersecting point 410 of optical axes 402a, 404a, 408a of the above three straight waveguides 402, 404, 408, and the first straight waveguide 402 defines a mirror image of the second straight waveguide 404 relative to the reflection center plane 406a.
In Patent Publication 1, although only propagation of two lights having respective wavelengths of 1.3 μm and 1.5 μm is described, propagation of three lights having respective wavelengths can be achieved. For example, in the straight-waveguide type optical multiplexer/demultiplexer device 400 shown in FIG. 16, when the optical filter 406 is an LPF (Long wavelength Pass Filter) allowing a light having a wavelength zone of 1.55 μm to be transmitted therethrough and reflecting lights having respective wavelength zones of 1.49 μm and 1.31 μm, a light having a wavelength of 1.55 μm and input into the first straight waveguide 402 is transmitted through the optical filter 406 to the third straight waveguide 408, and lights having respective wavelengths of 1.49 μm and 1.31 μm are reflected at the optical filter 406 and transmitted to the second straight waveguide 404.
Further, referring to FIG. 17, a multimode-optical-waveguide type optical multiplexer/demultiplexer device employing one optical filter and shown in FIG. 9 in Patent Publication 1 will be explained. FIG. 17 is a schematic view of the multimode-optical-waveguide type optical multiplexer/demultiplexer device. The multimode-optical-waveguide type optical multiplexer/demultiplexer device 420 has first and second multimode-interference type optical waveguide sections 424, 426 disposed on the opposite sides of an optical filter 422 to sandwich it, first and second single-mode optical waveguides 428, 430 connected to the first multimode waveguide section 424, and a third single-mode optical waveguide 432 connected to the second multimode waveguide section 426. The optical filter 422 is made of a dielectric multilayer film reflecting a light having a wavelength of 1.3 μm and allowing a light having a wavelength of 1.5 μm to be transmitted therethrough when each of these lights is input into the optical filter 422 at an incident angle of 0 degree.
In Patent Publication 1, although only propagation of two lights having respective wavelengths of 1.3 μm and 1.5 μm is described, propagation of three lights having respective wavelengths can be achieved. For example, in the multimode-interference type optical multiplexer/demultiplexer device 420 shown in FIG. 17, when the optical filter 422 is an LPF (Long wavelength Pass Filter) allowing a light having a wavelength zone of 1.55 μm to be transmitted therethrough and reflecting lights having respective wavelength zones of 1.49 μm and 1.31 μm, a light having a wavelength of 1.55 μm and input through the first single-mode waveguide 428 into the first multimode waveguide section 424 is transmitted through the optical filter 422 and the second multimode waveguide section 426 to the third single-mode waveguide 432, and lights having respective wavelengths of 1.49 μm and 1.31 μm are reflected at the optical filter 422 and transmitted through the first multimode waveguide section 424 to the second single-mode waveguide 430.
Next, referring to FIG. 18, a rod-lens type optical multiplexer/demultiplexer device disclosed in Non-Patent Publication 1 will be explained. FIG. 18 is a schematic view of a rod-lens type optical multiplexer/demultiplexer device. A rod-lens type optical multiplexer/demultiplexer device 440 has first and second rod lens sections 444, 446 disposed on the opposite sides of an optical filter 442 to sandwich it, first and second optical fibers 448, 450 connected to the first rod lens section 444, and a third optical fiber 452 connected to the second rod lens section 446. The optical filter 442 is made of a dielectric multilayer film. Each of the rod lens sections 444, 446 is provided with a gradient of refractive index inside thereof so that a light beam input into the rod lens sections 444, 446 is collimated, namely, changed into a parallel beam of light, or focused to a point. For example, when a length of the rod lens sections 444, 446 is a quarter of a pitch which is a cycle of a serpentine light path depending on a wavelength of a light, a beam of light input at one end of the rod lens sections 444, 446 is changed into a parallel beam of light at the other end thereof.
When the optical filter 442 is an LPF (Long wavelength Pass Filter) allowing a light having a wavelength zone of 1.55 μm to be transmitted therethrough and reflecting lights having respective wavelength zones of 1.49 μm and 1.31 μm, a light having a wavelength of 1.55 μm and input into the first optical fiber 448 is transmitted through the optical filter 442 to the third optical fiber 452, a light having a wavelength of 1.49 μm and input into the first optical fiber 448 is reflected at the optical filter 442 and transmitted to the second optical fiber 450, and a light having a wavelengths of 1.31 μm and input into the second optical fiber 450 is reflected at the optical filter 442 and transmitted to the first optical fiber 448.
Patent Publication 1: Japanese Patent Laid-open Publication No. 2002-6155 (FIGS. 1 and 3)
Non-Patent Publication 1: Hironori Tanaka et al., Collected Lecture Papers from General Convention of the Institute of Electronics, Information, and Communication Engineers, March, 2004, p. 276, C-3-102; “Development of Optical Multiplexer/demultiplexer Device Having a High Isolation Property”
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
In a modern communication system, signals may be transmitted from a source location to a destination location in analog or digital forms. Digital data communication has become more and more popular due to its various advantages in various applications. For example, it may offer increased capacity of data transmission, increased flexibility of data manipulation, etc. A signal that contains data derived from an image, a speech, etc., are typically encoded into sequences of symbols or binary symbols, which are then transmitted from a transmitter to a receiver through a data communication channel, e.g., via a cable or over-the-air. When transmitted through the communication channel, signals may be susceptible to interferences or noises, which may cause errors in the information on the receiver.
Certain techniques were developed to reduce data transmission errors in communication or to improve reliability of data communication. One example uses turbo codes, which may offer the performance approaching the Shannon limit, a theoretical limit for the maximum data transmission rate when data is transmitted over a noisy channel.
FIG. 1 illustrates a conventional non-binary (i.e., symbol-level) turbo code encoder 10 known in the prior art. Encoder 10 may include a grouping circuit 20, a permutation block 30, a modification block 40, a first non-binary convolutional code encoder 50 (C1), and a second non-binary convolutional code encoder 60 (C2). In FIG. 1, permutation block 30 and modification block 40 form a symbol-level interleaver, which processes input sequence u0 by symbols.
For example, an input sequence u0 having n binary bits may be grouped into N=n/W symbols (n and W both being positive integers, and typically n>W, and n being dividable by W) by the grouping circuit 20. Each symbol may include W binary bits from the input sequence u0. The grouped input sequence u0 may be directed through various circuits for processing. For example, the input sequence u0 may be directly output as an output sequence Y0 (Y0=u0) without any treatment. The input sequence u0 may also be directed to the first non-binary convolutional code encoder 50 (C1), where the input sequence u0 may be transformed and output as an output sequence Y1, which may have m bits (m may be a different integer from n, e.g., m>n). The input sequence u0 may further be directed to the permutation block 30 and the modification block 40 before being directed to the second non-binary convolutional code encoder 60 (C2). The second non-binary convolutional code encoder 60 (C2) may transform the sequence u2 and output the transformed sequence as an output sequence Y2, which may have m bits.
In the permutation block 30, the n/W symbols of the input sequence u0 may be permuted, the details of which will be discussed below. After permutation, the input sequence u0 may become a permuted sequence u1. Symbols in the permuted sequence us may be selectively modified by the modification block 40 according to a predetermined rule, which will be discussed in detail below. After the modification process, the sequence u1 may become a modified sequence u2. Finally, the modified sequence u2 may be directed into the second non-binary convolutional code encoders 60 (C2) for further processing.
A sequence u0 of n binary bits may be transformed into a sequence of m binary bits after being processed by the first and second encoders 50 (C1) and 60 (C2), where m>n, and the ratio of n/m is known as “code rate.” The first and second non-binary convolutional code encoders 50 (C1) and 60 (C2) may be structurally identical to each other, or different from each other. The first and second non-binary convolutional code encoders 50 (C1) and 60 (C2) may be implemented with different algorithms. For example, in some applications, the first non-binary convolutional code encoder 50 (C1) may output an output sequence Y1 with m1 bits (not shown in FIG. 1) and the second non-binary convolutional code encoder 60 (C2) may output an output sequence Y2 with m2 bits, where m1 may be different from m2. Therefore, in some embodiments, the first and second non-binary convolutional code encoders 50 (C1) and 60 (C2) may have different code rates. Since the first and second non-binary convolutional code encoders 50 (C1) and 60 (C2) are well known in the art, their details are not discussed herein.
FIG. 2 shows a diagram illustrating a non-binary turbo code encoder 70 with W=2 for a non-binary (symbol-level) turbo code defined in standards such as IEEE 802.16, DVB-RCS/RCT, etc. The input of the non-binary turbo code encoder 70 is a non-binary symbol, denoted as Sm, which may include a pair of data (A, B), where A and B are data units. An interleaver 80 of the non-binary turbo code encoder 70 may be a symbol-level interleaver, which may include the permutation block 30 and the modification block 40 shown in FIG. 1. The interleaver 80 may perform intra-symbol permutations or inter-symbol permutations. An intra-symbol permutation refers to a permutation within a symbol. For example, the data pair (A, B) may be permutated via an intra-symbol permutation to become another data pair (B, A). An inter-symbol permutation means a permutation between symbols. For example, a sequence containing a plurality of symbols [Sm,0, Sm,1, . . . , Sm,N−1] may be permutated to become another sequence containing the same symbols but arranged in a different order, e.g., [Sm,0, Sm,4, Sm,8, . . . , Sm,k], where k is a number from 0, 1, 2, . . . , N−1, and is determined based on a predetermined rule or algorithm.
Table 1 shows a conventional non-binary MAP algorithm known in the art, which may be implemented in the symbol-level interleaver 80. The algorithm includes two steps. Step 1 performs the intra-symbol permutation, for example, via the permutation block 30, and Step 2 performs the inter-symbol permutation using “Almost Regular Permutation (ARP),” for example, via the modification block 40. Before Step 1, a first sequence u0 may have already been grouped by the grouping circuit 20 shown in FIG. 1 into u0=[(A0, B0), (A1, B1), (A2, B2), (A3, B3), . . . , (AN−1, BN−1)], where data pair (Ai, Bi) includes a first data unit Ai and a second data unit Bi. In Step 1, each data pair (Ai, Bi) in the first sequence u0 is permuted between the first and second data units Ai and Bi, i.e., (Ai, Bi)→(Bi, Ai), if the condition (i mod 2=1) is satisfied, i=0, 1, 2, . . . , N−1. After permutation, a second sequence u1 may be generated from the first sequence u0. In Step 2, inter-symbol permutation is conducted. The jth data pair of a third interleaved sequence u2 is formed by the P(j)th data pair, which may be (Aj, Bj) or (Bj, Aj), of the second sequence u1, where P(j) is a mapping function providing a corresponding coordinate (i.e., address) of the jth data pair of the third sequence u2 in the second sequence u1. For an IEEE 802.16 symbol-level interleaver, the parameters P0, P1, P2, P3 used in the mapping function P(j) are constants known in the art, which are shown in Table 2.
TABLE 1IEEE 802.16 Symbol-Level Interleaver (Prior Art)Step 1: Switch alternate data pairs Let the sequence u0 = [(A0,B0), (A1,B1), (A2,B2), (A3,B3), ..., (AN−1,BN−1)] be the input to first encoder C1. for i=0, 1,..., N−1 if ( (i mod 2) = 1), let (Ai,Bi)→ (Bi,Ai) (i.e., switch the data pair) This step gives a sequence u1=[(A0,B0),(B1,A1),(A2,B2),...,(BN−1,AN−1)]=[u1(0),u1(1),u1(2), u1(3), ...,u1(N−1)].Step 2: P(j) The function P(j) provides the coordinate (i.e., address) of the data pair of the sequence u1 that is mapped onto the coordinate (i.e., address) jth data pair of an interleaved sequence u2 (i.e., u2(j) = u1(P(j))). for j=0, 1,..., N−1 switch (j mod 4) : case 0: P (j)= (P0j +1) mod N case 1: P (j)= (P0j +1+N/2+P1) mod N case 2: P (j)= (P0j +1+P2) mod N case 3: P (j)= (P0j +1+N/2+P3) mod N This step gives sequence u2=[u1(P(0)),u1(P(1)),u1(P(2)),u1(P(3)),...,u1(P(N−1))]= [(BP(0),AP(0)), (AP(1),BP(1)),(BP(2),AP(2)),(AP(3),BP(3)),...,(AP(N−1),BP(N−1))]. Sequence u2 is the input to second encoder C2.
TABLE 2Parameters for IEEE 802.16 Convolutional TurboCode Interleaver (Prior Art)InterleaverLength (Bytes)P0P1P2P3650009111801812132402418116062474824722711545623013600603617747224511900904811964814454131080108601312060180120536212224043643008243604372036054048031824166005366242
In a symbol-level interleaver design, the algorithm shown in Table 1 may require extra memory space for storing extrinsic information and a priori information generated during data processing in the decoder. As a result, the symbol-level interleaver 80 leads to higher complexity in decoder and may result in performance degradation in some applications in terms of higher error rates.
The disclosed embodiments may be directed to provide improvement(s) or alternative(s) to existing technology in certain data communication applications.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
This invention relates generally to systems and methods for analyzing, varying, testing, managing, and/or improving transmission in the communication spectrum.
2. Description of the Related Art
Broadcasting includes the distribution of audio, video, and/or data signals from a point of communication to one or more devices and from the one or more devices to the point of communication.
There has also been extensive growth in communications throughout the world. Many separate entities are involved. Furthermore, these entities are typically assigned specific portions of the communication spectrum within defined regions.
For example, communication systems are often regulated by one or more government organizations. In the United States, for instance, the Federal Communications Commission (FCC) licenses radio and television stations. Further, the FCC regulates the broadcast frequency, the transmission power, the distance between stations, and the like so that the communication facilities provide improved service in service coverage areas for the benefit of the public. The FAA (Federal Avionics Administration), in an example, determines the allowable tower height. The FCC confirms that the tower height has been accepted by the FAA before listing the tower in a tower database. The Antenna Structure Registration (ASR) database is an example of an FCC tower database.
Population growth, changing demographics, and improvements in broadcasting technologies, however, have created needs for new and improved communication techniques. Unfortunately, making improvements and modifications to existing communication systems is a highly complex process as improvements and modifications made to one point of communication may encroach on the rights of other facilities or may violate governmental rules and regulations.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Conventionally, as this sort of semiconductor capacitance type sensor, for example, semiconductor mechanical amount sensors such as acceleration sensors and angular velocity sensors have been proposed (in, for example, JP-A-2004-271312 corresponding to US Patent Application Publication No. 2004-0173913). These semiconductor capacitance type sensors correspond to such sensors equipped with sensor chips having movable electrodes and fixed electrodes and functioning as capacitance changing portions. Then, when mechanical amounts such as acceleration and angular velocities are applied to such sensor chips, distances between the movable electrodes and the fixed electrodes are changed, so that capacitance changes may be conducted.
Then, while these sensor chips are assembled with circuit chips, the capacitance changes of these sensor chips are converted into voltage changes, namely, voltage signals by CV converting circuits (namely, capacitance-to-voltage converting circuits) provided in the circuit chips. Thereafter, the voltage signals are outputted as sensor signals, so that the applied mechanical amounts are measured.
Such semiconductor capacitance type sensors have been manufactured as follows: That is, while sensor chips and circuit chips are manufactured respectively by performing semiconductor process operations, characteristics of the sensor chips are tested under condition of a single sensor chip, and thereafter, such sensor chips which are judged as good products are assembled with the circuit chips, and thus, these sensor chips and circuit chips are electrically connected to each other.
In general, characteristic testing operations as to sensor chips are carried out in such a way that capacitance changes in capacitance changing portions are checked by employing such testers as an LCR meter. While probes of the testers are attached to pads of the sensor chips, capacitances of the capacitance changing portions are converted into voltages within the testers under this condition in order to test the sensor characteristics.
Also, as methods for measuring capacitances of semiconductor capacitance type sensors other than the above-described capacitance measuring methods, conventionally, another method for measuring capacitance values has been proposed (in JP-A-2000-321300). That is, in this capacitance value measuring method, while a plurality of sensor chips are employed, capacitance values of these sensor chips are measured, and asymptotes are calculated which represent a relationship between the measured capacitance values and distances defined between the capacitances and the electrodes, so that the capacitance values are acquired.
In the above-described method for testing the sensor characteristics under the single sensor chip condition by utilizing the tester, stray capacitances produced at the probe portion of the tester which are attached to the pads provided in the sensor chip and stray capacitances of these pads are large, for example, approximately 1 pF to 100 pF, with respect to very small capacitance values (for example, approximately 1 pF) of the capacitance changing portions.
As a result, the conventional characteristic testing methods have the following problems. That is, errors contained in the capacitance values acquired by the testing operations become large with respect to the capacitance values of the sensor chips under such a condition that these sensor chips are electrically connected to the circuit chips, namely under packaging condition of the sensor chips, so that the high-precision capacitance value measuring operations can be hardly carried out.
Also, in the measuring method, although the capacitance values are predicted by employing the asymptotes, the adverse influence caused by the stray capacitance can be hardly avoided. Thus, there are some possibilities that the errors contained in the capacitance values measured by this method become larger with respect to the capacitance values under the packaging condition.
Also, another characteristic testing method may be conceived. That is, sensor chips are assembled with circuit chips, which are cut out from a wafer, so as to be brought into packaging members. Thereafter, a characteristic as to each of these packaging members under packaging condition may be tested. However, in this conceivable method, a large number of these packaging members must be picked up one by one, and these picked packaging members must be separately mounted on a testing apparatus, resulting in cumbersome handling operations.
Furthermore, another testing method may be conceived. That is, a wafer where structural members which constitute sensor chips have been formed is employed before the sensor chips are cut out, and then, an electric testing operation is carried out under present condition of this wafer. However, in this conceivable method, since probes of a tester are attached to pads of the wafer, materials of these pads are scooped out. Thus, there are some risks that the scooped materials are adhered as alien substances to capacitance changing portions.
Therefore, it is required to provide a packaging condition with a superior handling characteristic when a characteristic testing operation is carried out, and furthermore, while avoiding that alien substances are adhered onto the capacitance changing portions, the characteristic testing operations of the sensor chips can be carried out.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
In general, a combined cycle power generation system includes a gas turbine, a steam turbine, a steam cycle, and a multiple pressure combined cycle heat recovery steam generator (HRSG). Steam supply to the steam turbine from the HRSG must be temperature controlled in order to keep the steam temperature from exceeding the rated temperature of the HRSG, interconnecting steam piping, and the steam turbine. One method for controlling and limiting steam temperature includes injection of a water spray into a conventional spray attemperator located upstream (in relation to steam flow) of the final reheater and superheater passes. The water source is typically a high pressure feedwater pump located upstream of at least one economizer disposed within the HRSG.
Though water spray attemperation effectively controls and limits steam temperature, the water used in the spray can contain contaminants damaging to the gas/steam turbine. Water spray attemperation also causes significant reduction in combined cycle performance and efficiency due to the latent heat required for vaporization of the attemperation spray water, which effectively comes from the high level exhaust energy. There is a desire, therefore, for a combined cycle power generation system that controls/limits steam temperature without incurring a performance penalty resulting from use of high level exhaust energy to supply the latent heat of vaporization associated with water spray attemperation.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to scanning optical microscopes and, more particularly, to a laser scanning microscope (LSM) that performs focal point movement along the direction of the optical axis by using a wavefront converting element.
2. Discussion of Related Art
It has heretofore been necessary in order to obtain a three-dimensional image of a specimen with an LSM, for example, to capture optical images of successive planes inside the specimen by mechanically moving either the specimen or the objective along the direction of the optical axis. With this method, however, it is difficult to realize positional control with high accuracy and high reproducibility because the method needs mechanical drive. In a case where the specimen is moved, high-speed scanning cannot be effected when the specimen is large in size.
In observation of a biological specimen, if the objective is scanned in the state of being in direct contact with the specimen or immersed in a culture solution of the specimen, vibrations of the objective adversely affect the specimen under observation.
To solve the above-described problems, Japanese Patent Application Unexamined Publication (KOKAI) No. Hei 11-101942 discloses an adaptive optical apparatus. The apparatus is a microscope having an optical element (wavefront converting element) capable of changing power. The arrangement of the microscope is shown in FIGS. 27 and 28. In this prior art, a wavefront converting element is inserted in either or both of a viewing optical path and an illuminating optical path to change the focal length of the optical system and to correct aberration due to the change of the focal length by using the wavefront converting element. With this arrangement, it is possible not only to form and move a focal point in the object space without changing the distance between the objective and the specimen but also to correct aberration.
In the above-described prior art, it is preferable to place the wavefront converting element in the pupil plane of the objective or at a position conjugate to the pupil plane from the viewpoint of allowing the wavefront converting element to effectively perform its functions of moving the focal point in the object space and making aberration correction. If the wavefront converting element is not conjugate to the pupil plane, illuminating light or image-forming light will pass at different positions on the wavefront converting element according to the height of the object detected by the objective. To perform focal point movement or aberration correction, the wavefront shape has to be changed according to the object height. If the wavefront shape cannot properly be changed, image quality is likely to degrade considerably in an area where the object height is high.
If the wavefront converting element is changed into an optimum shape in accordance with a change in the object height, even if the wavefront converting element is not conjugate to the pupil plane, it is possible to avoid image quality degradation in an area where the object height is high. To realize this, however, the wavefront converting element needs to be controlled at high speed so as to provide an optimum rotationally asymmetric configuration. This is extremely difficult.
For the reasons stated above, it is desirable that the wavefront converting element should be placed at a position conjugate to the pupil. This is, however, difficult to implement because of the following problems.
A variety of objectives are used in microscopic observation, and the pupil position differs for each objective. Therefore, when a plurality of objectives are switched from one to another to perform observation, it is difficult to keep the pupils of the objectives in conjugate relation to the wavefront converting element at all times.
Further, the wavefront converting element needs to be placed in conjugate relation to the position of a laser scanning member and also to the position of the objective pupil. Accordingly, at least two pupil relay optical systems are required. Therefore, the apparatus becomes large in size and complicated unfavorably.
Further, in the above-described prior art, a reflection type wavefront converting element is incorporated in the illuminating optical path or/and the light-detecting optical path. Therefore, the prior art uses beam splitters as shown in FIGS. 27 and 28. Accordingly, when a non-polarized laser is used as a light source, together with a non-polarization type beam splitter, the amount of light is reduced to ¼ every time the laser beam travels via the wavefront converting element.
More specifically, the amount of light is reduced to ¼ in the process of illumination and also reduced to ¼ in the process of detection. That is, the amount of light is reduced to 1/16 in total. If a linearly polarized laser is used as a light source, together with a polarization beam splitter and a quarter-wave plate, the loss of light in the process of illumination can be prevented. However, in observation of fluorescence in a non-polarized state, the amount of light is reduced to ½ in the process of (fluorescence) detection.
Further, even when a polarization beam splitter and a quarter-wave plate are used as stated above, it is not always possible to use a linearly polarized laser as a light source. If a non-polarized laser is used to observe fluorescence, the amount of light is reduced to ½ in the process of illumination and also reduced to ½ in the process of detection. That is, the amount of light is reduced to ¼ in total.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Related Applications
There are no applications related hereto now filed in this or any foreign country.
2. Field of Invention
This invention relates to a waler support bracket for use in a particular modular-type concrete form structure having external metal supporting studs providing joinder means to support such brackets.
3. Description of Prior Art
The instant bracket is an improvement over the waler bracket shown in my earlier patent, Unitized Metal Stud Form Structure, U.S. Pat. No. 3,730,476. The brackets are particularly adapted for usage with the form structure disclosed in that patent. The prior waler bracket provided an elongate fastening element adapted to be releasably carried by a vertical stud and an L-shaped arm extending horizontally outward to support a waler, primarily standard two by four dimension lumber maintained in the bracket by wedging. Subsequent to the prior invention, governmental safety requirements provided for placement of staging or scaffolding of a specified width at the top of any concrete wall form above some minimum height. In addition the staging was required to provide a toeboard and a guardrail to prevent slippage. The instant invention provides a new bracket to secure the required scaffolding with toeboard and guardrail to the form structure while also serving as a waler to thereby eliminate the need of separate staging, external to the forms. To do this, I provide a new waler bracket releasably attached to the form structure in a manner similar to my prior brackets but capably of supporting both the scaffold platform with toeboard and guardrail. My invention provides a simple, economic method whereby scaffolding can be erected on the top of a concrete wall form as a part thereof.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
The use of fossil fuel as the combustible fuel in engines results in the combustion products of carbon monoxide, carbon dioxide, water vapor, smoke and particulate, unburned hydrocarbons, nitrogen oxides and sulfur oxides. Of these above products carbon dioxide and water vapor are considered normal and unobjectionable. In most applications, governmental imposed regulations are restricting the amount of pollutants being emitted in the exhaust gases.
In the past, NO.sub.x emissions have been reduced by reducing the intake manifold temperature, retarding the injection timing, and modifying the injection rate shape. And, the adverse effects on fuel consumption, particulate emissions engine performance have largely been alleviated through improvements in the basic engine design and fuel selection. For example, at the present time smoke and particulates have normally been controlled by design modifications in the combustion chamber, particulates are normally controlled by traps and filters, and sulfur oxides are normally controlled by the selection of fuels being low in total sulfur. This leaves carbon monoxide, unburned hydrocarbons and nitrogen oxides as the emission constituents of primary concern in the exhaust gas being emitted from the engine.
Many systems have been developed for recycling a portion of the exhaust gas through the engine thereby reducing the emission of these constituents into the atmosphere. The recirculation of a portion of exhaust gas is used to reduce NO.sub.x pollution emitted to atmosphere. In a naturally aspirated engine this process is relatively simple. But, with a turbocharged, the recirculation of a portion of the exhaust gas into the intake air becomes more complex because the intake pressure may be higher than the exhaust pressure during operating conditions. In many of such past system a volume of the exhaust gas from the engine was redirected to the intake air of the engine through the turbocharger and/or an aftercooler and to the engine. Such systems caused the premature plugging of aftercooler cores and malfunctioning of the systems. Additionally, with such recirculation system deterioration of the exhaust flow was caused by deposit buildup.
Prior turbocompounding systems typically use two turbines in series to raise the exhaust manifold pressure above the intake air. However, turbocompounded engines operating at low engine speeds operate inefficiently due to the decrease in the pressure ratio across the turbines in series. Prior techniques have coupled the compounded turbochargers to the engine using mechanical, hydraulic, and flexible couplings. Mechanical couplings need to be extremely strong to withstand the inertia of the turbine, thus adding cost to the coupling. Hydraulic couplings may be used but add complication to the system and additional losses of efficiency during engine operation. Flexible elements may also be used but may have a resonance problem due to the overlapping of frequencies of the flexible coupling the engine.
Various approaches have been used to address the adverse pressure gradient issue. For example, throttling valves have been installed in the air inlet, back pressure valves in the exhaust gas, intake manifold venturi tubes, etc. to provide sufficient pressure drop to get the exhaust gas to flow to the intake air. Although this provides the necessary pressure drop to functionally operate an exhaust gas recirculation system several disadvantages, such as, fuel consumption, emissions, and/or performance occur. In particular, exhaust gas systems which utilize a turbocharger have several performance disadvantages, such as balancing between the turbocharger compressor and turbine portions and turbine operating efficiencies.
The present invention is directed to overcoming one or more of the problem as set forth above.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
It is known from the state of the art that in vehicles, particularly motor vehicles, fresh air enters through openings of the vehicle, like for example a radiator grill, and the air stream is guided to the radiator device of the vehicle. Hereby it can be ensured that for example an engine of the vehicle is efficiently and reliably cooled and/or that the vehicle interior can be efficiently air conditioned. Thereby a device for the regulation of the airstream can be used in order to at least partially close openings of the vehicle via cover elements and therewith to at least partially avoid an air entry. This effects that for example an air cushion is reduced, the cold run phase is shortened and the operating temperature of the engine is reached faster. Therewith the CO2 emission of the vehicle is reduced and the cw-value (drag coefficient of the vehicle) can be optimized.
Disadvantageously with known solutions for such devices for controlling the airstream is that these are complex in the production and assembly. Particularly an assembly of the cover elements at the carrier is extensive, wherein the cover elements have to be introduced in corresponding bearing acceptances in a carrier of the device for a pivotable bearing. This is often connected to additional working steps for example the removal and renewed fastening of elements of the carrier which enable the insertion of the cover elements. Often the cover elements have to be hidden elastically for the assembly by an influence of force in order to shorten those in a longitudinal direction such that an assembly is enabled in a closed carrier. Hereby the risk occurs for a damage of the cover elements due to the bending, wherein additionally the assembly is difficult, error-prone and complicated.
It is therefore the object of the present invention to at least partially avoid the previously described disadvantages. Particularly it is the object of the present invention to enable a simplified, secure and fast and moreover error-free assembly.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Laser surgery has experienced an exponential growth in recent years. Approximately 4,000 laser surgeries per day are now being performed in the U.S. Lasers are being used in almost every conceivable kind of surgery, from correcting eye dysfunctions to removing warts and corns from the bottom of the foot. Laser surgery is also being increasingly utilized in cancer therapy as well, wherein cancerous tissue is vaporized by a laser beam of a preselected wavelength.
Laser surgery offers many benefits to the patient such as lower cost, reduced length of hospital stay and reduced recovery time since major incisions are often not as necessary as they are in conventional types of surgery. However, it now appears that laser surgery is posing serious health risks to the physician performing the surgery, the nurses attending the physician and the rest of the supporting personnel in the operating room. An increased number of lesions have been noticed in the personnel that perform or assist during laser surgeries. Lesions and other precancerous conditions such as papillomas and chondylomas are appearing at increasing rates on the face, eyes, nose, hands, lips and the larynx and lungs of those performing these surgeries.
During laser surgery of cancerous tissue the malignant tissue is vaporized by a laser beam. This vaporization produces gaseous by-products which can carry infectious, live virus into the surrounding air of the operating room. Gaseous by-products such as smoke can also be produced in conventional types of surgery wherein a surgeon uses an electric scalpel or thermal cauterizer during a surgical procedure. The smoke produced using these instruments often carries infectious virus into the atmosphere of the operating room as well as interfering with a surgeon's view of the surgical site. The live viruses or other materials contained in the gaseous surgical by-products can also adhere onto the eyes, skin and lungs of the personnel in the operating room, causing the above-mentioned lesions.
In laser surgery, a surgeon employs a high intensity laser beam of a preselected wavelength to vaporize infected or tumorous tissue. A smoke plume is often produced as a result of this vaporization. In heretofore employed techniques, the plume of gaseous by-products produced during this surgery was vented directly into the air of the operating room, possibly infecting those in the room. In some instances, a suction wand was maintained proximate the surgical site by an assistant; however these wands are generally rather narrow and hence not very effective at capturing the smoke plume. Additionally, such efforts have been found to interfere with the surgeon's actions. It is therefore desirable to provide a smoke evacuation system for effectively evacuating these infections, gaseous by-products produced during surgery.
U.S. Pat. No. 4,735,603 to Goodson et al. discloses an intra-abdominal laser smoke evacuation system and method for removing the laser smoke from the site of a laser laparoscopy. Disclosed therein is a closed-loop system wherein CO.sub.2 gas is pumped through a Laparoscopic tube into a body cavity. The laser generated smoke mixes with the pumped-in CO.sub.2 gas which is then vented through a second laparoscopic tube inserted into the patient. This intra-abdominal system removes only laser smoke produced during laparoscopic surgical procedures and requires insertion of at least two tubes into a patient's body as well as maintenance of a flow of CO.sub.2 gas through the patient's body. This system requires a CO.sub.2 gas pump, a discharge line connected with the pump, pressure sensors and inflators and is restricted solely to laparoscopic surgeries.
U.S. Pat. No. 4,487,606 to Leviton et al. discloses a suction canister assembly for aspirating and collecting liquids and gasses, produced during the surgery. The canister is a containment unit for receiving blood and other surgical by-products, but no means are provided for removing and/or sterilizing smoke produced at a surgical site.
It will thus be appreciated that there is yet a need for a smoke evacuation system which traps and evacuates all gaseous surgical by-products produced at a surgical site. The present invention addresses this problem by providing a smoke evacuation system for use in surgery which includes a portable evacuation hood for effectively trapping and evacuating gaseous surgical by-products at a surgical site. These and other advantages of the present invention will be readily apparent from the drawings, discussion, description and claims which follow.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Technical Field
The present disclosure relates to earphones and, particularly, to a carbon nanotube based earphone.
2. Description of Related Art
Conventional earphone generally includes an earphone housing and an sound wave generator disposed in the earphone housing. The earphones can be categorized by shape into ear-cup (or on-ear) type earphones, earphones, ear-hanging earphones. The earphones can be disposed in the ears of a user. The ear-cup type earphones and ear-hanging earphones are disposed outside and attached to the ears of a user. The ear-cup type earphones have circular or ellipsoid ear-pads that completely surround the ears. The ear-hanging type earphones have ear-pads that sit on top of the ears. The earphones can also be categorized as wired earphones and wireless earphones.
The earphone housing generally is a plastic or resin shell structure defining a hollow space therein. The sound wave generator inside the earphone housing is used to transform electrical signals into sound pressures that can be heard by human ears. Sound wave generators can be categorized according to working principles: electro-dynamic sound wave generators, electromagnetic sound wave generators, electrostatic sound wave generators and piezoelectric sound wave generators. However, all known sound wave generators use mechanical vibrations to produce sound waves and rely on “electro-mechanical-acoustic” conversion. The electro-dynamic sound wave generators are most widely used. However, the structure of the electric-powered sound wave generator is constricted by configurations of magnetic fields and magnets which are often heavy in weight.
Carbon nanotubes (CNT) are a novel carbonaceous material and have received a great deal of interest since the early 1990s. Carbon nanotubes have interesting and potentially useful electrical and mechanical properties, and have been widely used in many different fields.
What is needed, therefore, is to provide an earphone having a simple lightweight structure.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Optoelectronic device, such as image sensors and photovoltaic devices, may include optically sensitive material. Example image sensors include devices that use silicon both for the sensing function and for the read-out electronics and multiplexing functions. In some image sensors, optically sensitive silicon photodiodes and electronics may be formed on a single silicon wafer. Other example image sensors may employ a distinct material, such as InGaAs (for short-wave IR sensing), or amorphous selenium (for x-ray sensing), for the sensing (photon to electron conversion) function. Example photovoltaic devices include solar cells that use crystalline silicon wafers for photon to electron conversion. Other example photovoltaic devices may use a separate layer of material such as amorphous silicon or polycrystalline silicon or a distinct material for photon to electron conversion. However, these image sensors and photovoltaic devices have been known to have a number of limitations.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
1. Field of the Invention
The present invention relates to the control of multiple wireless radios of differing radio types contained in a single computing device, such as a desktop personal computer, a laptop personal computer, a personal digital assistant (PDA), or the like.
2. Description of Prior Art
As shown in FIG. 1, a personal electronic device 10, such as personal computer (PC), personal digital assistant (PDA), or cellular phone may have disparate radios 11a-11e using disparate radio technologies and communication protocols in an environment having remote wireless devices 14a-14p. The remote wireless devices 14a-14p are accessible through the radios 11a-11e using the disparate radio technologies.
For instance, as shown, the personal electronic device 10 may have a GSM/CDMA cellular radio 11a, a Wi-Fi (IEEE 802.11) radio 11b, a UWB (Ultra-wide Band) radio 11c, a Bluetooth radio 11d, and another radio 11e that represents future radios having unforeseen but equivalent wireless communication technologies. The remote wireless devices may include: a cellular network 14a; a first access point 14b and a second access point 14c using Wi-Fi technology; a third access point 14d, a fourth access point 14e, a wireless USB hub 14f, a PDA 14g, a first printer 14h, a first computer 14i, an first input device 14j, and a first audio device 14k using UWB technology; a second computer 14l, a second input device 14m, and a second printer 14n using Bluetooth technology; and a remote wireless device 14p that represents future remote wireless devices using unforeseen but equivalent radio technology.
Each individual radio 11a-11e has an individual utility that is used to manage and control the radio. This is largely a result of the local radio types having different physical (PHY) layers, different medium access control (MAC) portions of the data link layer (DLL), and, therefore, different device drivers and different utilities (user interface applications) on the personal electronic device for control of the local wireless radios. Users get confused because they don't know which utilities they are to use to manage and control which radio in order to use a remote wireless device. Thus, there is a need for a single utility that can be used with all of the local radios 11a-11e, to eliminate the need for a user to know what radio technology is being used to access remote wireless devices 14a-14p, and allow the user to identify the remote wireless device that they wish to use without regard to the radio or technology used to access the remote device or the utility used to control the radio.
Further, the software developer that is developing applications that utilize the local wireless radios to connect to remote wireless devices must currently use different command structures to perform similar generic functions (such as find devices, connect/disconnect devices, set security, etc.). Again, this condition is the result of the different radio types having fundamentally different interfaces on multiple levels. Thus, there is a need for a utility that allows developers to treat different wireless radio types generically, and to allow third-party applications to access the functionality of such a utility.
|
{
"pile_set_name": "USPTO Backgrounds"
}
|
Subsets and Splits
No community queries yet
The top public SQL queries from the community will appear here once available.