A Wilton-type carpet and methods of making integral fringes on it, of affixing a decorative border around the periphery of the carpet and of inlaying decorative strands within the design of the carpet. The method creates integral fringes by the one way looming of the face yarns and by the severance of two transverse backing strands. The backing is undone while simultaneously releasing face yarns to act as the fringes. The method also provides a shelf at the fringe/carpet face interface allowing for a decorative trim to be affixed thereto. Another aspect of the method entails the complete removal of face yarns at both left and right sides to result in a shelf along the left and right sides to which decorative trim can be affixed. The face yarns within the carpet face can be removed in both the longitudinal and transverse directions to inlay decorative yarn therein.

This invention relates generally to woven carpets and, more particularly to the fringing, decorative bordering and the inlaying of independent strands into the face design of Wilton carpets.
The Wilton carpet is one type of woven carpet, where the face yarn is woven into the backing material, not just fastened to the backing with adhesive as are tufted carpets. The Wilton carpet, named for the town in England where this type of carpet looming originated, is distinguished by the layering of its face yarns: the Wilton loom uses up to as many as six different yarns to form the pile--the design in the carpet face. Although it varies from carpet to carpet, one face yarn is the dominant yarn whose loops form the majority of the carpet design. Where the design requires a yarn of a different color or texture, that yarn forms a loop in the design. Otherwise, this least-used strand remains buried beneath the dominant yarn, running in a parallel direction through the carpet backing. The face yarn and all its underlying yarns are woven in one direction: the longitudinal direction. There are no yarns woven in the transverse direction.
Usually, the Wilton carpet border is finished off with a binding--a fabric sewn around the periphery of the carpet. This binding hides the cut ends of the face yarns and backing strands and also serves to keep these yarns and strands from fraying and unraveling. However, the binding detracts from the overall appearance of the carpet due to its "non-integral" nature. This can be further aggravated by the visibility of any stitching used to affix the binding to the carpet.
For clarity of fiber orientation, strands running in the direction of loom motion, i.e., the longitudinal direction, are known as warp strands. Strands running perpendicular to the loom motion, i.e., the transverse direction, are known as weft strands.
The following constitute examples of various types of prior art involving woven carpets in general concerning fringing and the inlaying of independent yarns into the carpet design as found in the following U.S. Pat. Nos. 647,100 (Kross); 1,310,902 (Ayres); 1,899,219 (Underwood); 2,141,386 (Habib); 3,279,026 (Strauss et al.); 3,727,645 (Jowett); 5,027,483 (Anderson).
The method disclosed by Kross requires narrow strips of used woven fabric be fed into an apparatus that cuts the warp threads on each edge of the fabric strip at short intervals. After the fabric is removed from the machine and the cut warp strands are shaken out, the result is a fabric strip with fringes along the longitudinal sides of the strip. These fringes, consisting of weft fibers, are then woven into an article to be fringed.
The method disclosed by Ayres is to create integral fringing from the weft strands rather than from the warp strands. The result of the Ayres' method is that the width of the fabric as woven becomes the length of the carpet and instead of the warp strands being the longer threads of such carpet, the weft fibers are the longer. In the production of the woven fabric, just within the longitudinal sides of the fabric, there is a band of fabric where warp strands are highly dispersed. Everywhere else, at the very edge of the longitudinal sides and outside the band, both weft and warp strands occur in their usual density. Upon removal of the fabric, the dispersed warp strands in the band are removed and a plurality of weft strands are twisted with each other within the band. These twists are then glued or latexed to permanently maintain the twisting. Following this, the longitudinal sides of the fabric are cut off, leaving a woven fabric with fringes on the sides perpendicular to the loom motion.
The method disclosed by Underwood creates fringes, independent of the carpet itself, which are then attached to the border of the carpet which is to have fringing, i.e., the entire fabric consists of multiple fringe segments that can be cut from the fabric and applied to another carpet. A fringe segment consists of a body to which the fringes are attached. Once the fabric is woven, it largely consists of weft strands. These strands will form the fringes for every fringe segment. Uniformly dispersed along the weft strands are two perpendicular and adjacent bands of woven weft and warp strands. These two bands (pair) are separated from one another by small lengths of weft strands. The pair will form the body of the fringe segment. Starting from one end of the fabric, and midway between the first two pairs, the weft strands are cut. What has been removed is a fringe segment. The fringe segment is folded over such that the two bands are on top of one another. This folded-over segment is the body of the fringe segment and is then sewn onto the border of the carpet which is to have fringing.
The method disclosed by Habib is similar to that disclosed by Ayres in creating the fringes of a woven fabric. Under the Habib teaching, the weft strands are also used for the fringes rather than the warp strands. However, in creating the longitudinal bands, no warp strands are used. Once the fabric is removed from the loom, the longitudinal edges need only be cut and the result is the same as taught by Ayres.
Strauss et al. discloses an apparatus for mechanically fraying and fringing the edge of a straight cut fabric of desired width of edge and to a desired depth or length of fringe. The apparatus uses a spindle to release a transverse yarn fiber. Depending on how far into the spindle the woven fabric is fed, determines the number of transverse yarn fibers released and thereby establishes the length of the fringes (i.e., the yarn fibers along the spindle axis from which the transverse yarns are released, form the fringes).
Jowett discloses a modification to a Wilton carpet loom which creates a passage across the width of the loom for insertion of pile wires (face yarn). The loom uses a movable guide to permit the insertion of a desired strand within the face of the fabric and then returns the loom to the mode it was in just before the insertion occurred. This apparatus permits the insertion of an independent fiber during the carpet's original production.
The method disclosed by Anderson is for selectively releasing tied yarns from a fringe strip, separating them and then presenting them for interweaving in a seam area. This method does not result in the creation of a fringe projecting from the edge of a carpet.
Based on this prior art, carpet fringes along the sides of the carpet have been created by manipulating the weft strands into fringes. To accomplish this, the looming had to be contrived so that free weft strands could be available upon the carpet's removal from the loom. This required the use of edge bands of woven warp and weft fibers to hold the carpet together during looming. Upon the carpet's removal from the loom and once the unwoven weft fibers were twisted and glued in such a manner as to not come apart, these edge bands were cut off and disposed of, leaving free weft fibers to act as fringes. Such "integral" fringing utilized the weft strands of the loomed carpet itself to act as fringes. Both Ayres and Habib teach such an integral weft strand method of creating a fringe. On the other hand, Underwood teaches the looming of "non-integral" or independent fringes which are then attached to the desired carpet to be fringed.
As the prior art stands, no method exists for creating fringing at the two ends of a Wilton carpet using integral fringes by way of the warp strands. The prior art has not provided for a Wilton carpet with integral fringe, nor a viable method of producing a fringed Wilton carpet. Thus, a need exists for the same.

Fringed wilton-type carpet and method of making the same


Provided is a system for wireless communications including several base stations supporting a wide area wireless network and several mobile user equipment (UE) devices. Each mobile UE device may be configured to transmit a request to establish a local wireless connection with one or more of the UE devices. The mobile UE device may receive a response containing connectivity information from each of the mobile UE devices and then select one of the mobile UE devices based on the connectivity information received from each of the mobile UE devices. The mobile UE device may then establish a local wireless connection with the selected mobile UE device. The mobile UE device may then communicate with one of the base stations in the wide area wireless network through the selected mobile UE device, utilizing the local wireless connection.

As the speed, complexity and functionality of mobile user equipment (UE) devices continue to increase, fluctuations in the signal strength or unavailability of the wide area wireless networks which support the mobile UE devices unacceptably limit the quality of wireless connections to users. For example, when a mobile UE device, such as a wireless smart phone, experiences poor signal quality, a user is typically required to change locations in order to restore a wireless connection to the network. Such sporadic wireless network coverage unacceptably limits the availability of bandwidth to individual mobile UE devices. To provide adequate wireless network coverage, service providers are required to build base stations and transmitting towers in the poor coverage areas, which can be prohibitively expensive.
Conversely, in densely populated areas, hundreds or thousands of mobile UE devices may compete for a limited amount of bandwidth on overcrowded wireless networks. Interference between the mobile UE devices in these areas can decrease the average efficiency of bandwidth usage to levels as low as 25%. Such decreased communication efficiencies can quickly drain the batteries of mobile UE devices which are forced to re-transmit and re-receive data during such periods of high network interference.

Efficiency of wireless wide area networks utilizing local wireless connections


A protective helmet having a rigid outer helmet shell, an inner pad assembly formed from a resilient material and threaded fasteners partially embedded in the inner pad assembly and adapted to secure the inner pad assembly into the outer helmet shell. The embedded fastener has a threaded aperture to receive a securement means such as a threaded screw, and a non-circular portion, which protrudes from the inner pad assembly and is inserted in a corresponding mounting hole on the outer helmet shell. The non-circular portion of the fastener prevents rotation of the fastener when the threaded securement means is fastened into the threaded aperture during installation or removal of the inner padding assembly.

The use of protective headgear in various types of sports or hazardous activities is well known. Conventional protective helmets have one or more inner pads secured by fasteners to the inner surfaces of a rigid helmet shell and are generally adapted to conform to the shape of a wearer's bead. One of the problems associated with the use of such helmet arises when the inner pads of the helmet are not properly fitted to the head of the user. Another disadvantage of known helmets is that the inner pads of the helmet are attached by metal rivets which do not permit removal of the inner pads and which may protrude into the helmet resulting in injury to the wearer upon impact.

Padding with embedded fastener for use in a helmet


A method for setting transactions of multiple data objects is provided. The method includes steps of: (a) a server acquiring information on multiple data objects used for a service object, and obtaining information on data sources which are set to correspond respectively to the data objects by referring to a setting file; and (b) the server determining the multiple data objects to be used by local transactions or distributed transactions by referring to the information on the data source.

To develop program that uses multiple data objects, developers generally have to determine whether data sources corresponding respectively to the data objects are homogeneous or heterogeneous and be concerned about how to set transactions of the multiple data objects as a result of the determination. As such, to solve the developers' concern, a technology of managing transactions by using user codes has been used.
However, it was difficult for the developers to unify transaction management.
In addition, program development complexity has increased because the developers must prepare the program in consideration of transaction management and it also had a problem of increased error possibility of the finally developed program due to the increased development complexity.
Such problems were not solved even by Korean Patent Laid-Open Publication No. 2000-0032756 titled "A Method for Preprocessing Transactions of Real-time Database Management System."
Therefore, the inventor intends to propose a method for allowing the developers to unify management of transactions by referring information on data sources which are set to correspond respectively to multiple data objects upon development of program that uses the multiple data objects.

Method, server and computer-readable recording media for setting transactions of multiple data objects


A semiconductor device includes a cavity portion formed in a supporting portion made of a semiconductor material so as to be surrounded by the supporting portion, and a silicon oxynitride film supported on one surface of the supporting portion so as to cover the cavity portion on the side of the one surface or a silicon oxynitride film supported on one surface of the supporting portion and so arranged as to form a bridged structure over the cavity portion. The composition of the silicon oxynitride film is selected in accordance with the material of the supporting portion. The former semiconductor device is produced by forming a silicon oxynitride film on one surface of a semiconductor substrate, forming an etching resistant film which has a pattern of a cavity portion, on another surface of the semiconductor substrate, and forming the cavity portion by selectively etching the semiconductor substrate using the etching resistant film as a mask until the formed cavity portion reaches said silicon oxynitride film. The latter semiconductor device is produced by the same process except that another step for patterning the silicon oxynitride film to form a bridge structure is included.

in recent years, in the field of sensors and actuators, it has been attempted to manufacture new devices, such as infrared sensors using abridged structure (thermobolometers), high-sensitivity capacitive pressure sensors using a very thin diaphragm, humidity sensors and audible range-controllable acoustic elements, by forming precision mechanical structures having a size of several microns on a substrate made of a semiconductor material, such as silicon.
Conventionally, in a case where a diaphragm structure of silicon having a smaller thickness than several microns is formed using silicon as a material, etching processing has been performed using alkaline etchant for example. In this case, it is important to control the stop timing of etching which influences the accuracy in the etching processing. As methods for stopping the etching, so called p-n etch-stop technique using p-n junction bias, and etch-stop technique using high-density impurity diffusion have been used ("TRANSDUCERS '87" pages 116-125).
however, in a case where a thin diaphragm is formed by the etch-stop technique using the p-n junction bias, an expensive epitaxial wafer is needed. Furthermore, this technique requires to establish an electrical contact with the p-type part and the n-type part of a silicon wafer immersed in an electrolytic solution, and to form these electrodes insulated from the electrolytic solution. However, it is technically difficult to satisfy these requirements. In the case of the etch-stop technique using the high-density impurity diffusion, it is difficult to selectively diffuse impurities, and heat treatment must be performed at a high temperature for a long time. In addition, it is difficult to control the concentration of impurity in the direction of depth. Moreover, since this technique can not cause the etching to be completely stopped, it is difficult to form a desired structure with high accuracy.
It has been known to produce a diaphragm or a bridged structure by laminating a silicon oxide film (SiOx) and a silicon nitride film (SiNy) on a silicon substrate and by etching apart of the silicon substrate. In this method, it is required to accurately control the conditions for the formations of the silicon oxide film and the silicon nitride film so as to ensure the counter balance between the elongation stress of the silicon oxide film and the contraction stress of the silicon nitride film. However, this control is very difficult in realization, and the product tends to be broken due to unbalance between the stresses applied to the respective films. Therefore, it is difficult to improve the yield of the diaphragm or the bridged structure.

Semiconductor device and method for production thereof


There is disposed a damper made of a synthetic resin having at least a column-shaped member (pillar-shaped member) of which one end and the other end come in contact with a support yoke and a yoke plug, respectively. This damper restrains a teeth beating noise generated by a rack and a pinion, from being propagated from the support yoke to the yoke plug, lowers its noise pressure level or changes its noise quality.

The present invention relates to a rack-pinion type steering apparatus to be used for a vehicle of an automobile or the like.
FIG. 3 is a section view of a main portion of a conventional rack-pinion type steering apparatus. As shown in FIG. 3, the conventional rack-pinion type steering apparatus has a pinion shaft 83 supported, rotatably with respect to a housing 80, by bearings 81, 82 and provided at the tip thereof with a pinion 83a, and a rack shaft 84 supported in a perpendicular direction to the pinion shaft 83 and having a rack 84a to be meshed with the pinion 83a. The pinion shaft 83 is connected to a steering wheel (not shown), and the rack shaft 84 is connected to steering wheels (not shown). A back side of the rack 84a of the rack shaft 84 is made, for example, in the form of a circular arc as shown in FIG. 3.
The housing 80 has a cylindrical support yoke housing hole 80a formed in a perpendicular direction to the rack shaft 84. Housed inside of the support yoke housing hole 80a are a support yoke 85 which supports the rack shaft 84 through a sliding contact member 86 arranged to come in sliding contact directly with the rack shaft 84, a yoke plug 87 disposed at the back side of the support yoke 85 for closing the support yoke housing hole 80a, and a spring 88 interposed, as compressed, between the support yoke 85 and the yoke plug 87.
The sliding contact member 86 is made of metal or a synthetic resin for receiving load exerted to the support yoke 85 from the rack shaft 84, and is mounted in a concaved portion formed in the support yoke 85 as shown in FIG. 3.
The yoke plug 87 is threadedly connected to the end of the support yoke housing hole 80a and is fixed to a predetermined position by a lock nut 89. The support yoke 85 is pushed to the rack shaft 84 by the spring 88 to apply a pre-load across the rack 84a and the pinion 83a.
However, in the above-mentioned conventional rack-pinion type steering apparatus, there are instances where vibration or impact load transmitted to the rack shaft 84 from the steering wheels, causes the rack 84a of the rack shaft 84 and the pinion 83a of the pinion shaft 83 to shake with respect to each other, thus producing a so-called teeth beating noise. Particularly, in the type in which there is applied, to the rack shaft 84, a VGR (Variable Gear Ratio) rack in which the gear ratio is lowered from the center toward the both ends, a high load may possibly be transmitted to the support yoke 85 from the rack shaft 84. Accordingly, the sliding contact member 86 is required to be made of metal. Thus, substantially all contact portions in the support yoke housing hole 80a are made of metal. Therefore, the teeth beating noise is successively propagated from the rack shaft 84 to the sliding contact member 86, the support yoke 85 and the yoke plug 87, and then transmitted to the outside through the housing 80. As a result, the conventional rack-pinion type steering apparatus is disadvantageous in that the teeth beating noise is transmitted, as abnormal noise, to the driver, causing the same to be unpleasant.
In view of the problem of prior art above-mentioned, it is an object of the present invention to provide a rack-pinion type steering apparatus capable of restraining a teeth beating noise generated due to shaking of the rack and the pinion with respect to each other, from being transmitted, as abnormal noise, to the driver, thus restraining the driver from becoming unpleasant.
To achieve the object above-mentioned, a rack-pinion type steering apparatus according to the present invention comprises:
a housing;
a pinion shaft supported rotatably with respect to the housing and provided at the tip thereof with a pinion;
a rack shaft provided on a lateral side thereof with a rack to be meshed with the pinion;
a support yoke slidably housed in a cylindrical support yoke housing hole formed in the housing for supporting the rack shaft at its back side;
a biasing member of which one end comes in contact with the support yoke for biasing the same toward the rack shaft such that the rack and the pinion are meshed with each other at a predetermined pressure;
a yoke plug attached to the housing for receiving the other end of the biasing member and for closing the support yoke housing hole; and
a damper made of a synthetic resin having at least a pillar-shaped member of which one end and the other end come in contact with the support yoke and the yoke plug, respectively.
In the rack-pinion type steering apparatus of the above construction, there is disposed the damper made of a synthetic resin having at least a pillar-shaped member of which one end and the other end come in contact with the support yoke and the yoke plug, respectively. Accordingly, even though a teeth beating noise is generated due to shaking of the rack and the pinion with respect to each other, the damper can restrain the teeth beating noise from being propagated from the support yoke to the yoke plug, lower the teeth beating noise in noise pressure level, or change the teeth beating noise in noise quality. This restrains the teeth beating noise from being transmitted, as abnormal noise, to the driver, thus restraining the driver from becoming unpleasant.
In the above rack-pinion type steering apparatus, the biasing member is formed by a compression coiled spring disposed at the center portion of the support yoke housing hole, and
the pillar-shaped member is disposed inside of the compression coiled spring, and the damper has a ring-shaped member disposed around the compression coiled spring with one end and the other end of the ring-shaped member coming in contact with the support yoke and the yoke plug, respectively.
In this case, both the pillar-shaped member and the ring-shaped member restrain the teeth beating noise from being propagated. Further, two separate members, i.e., the pillar-shaped member and the ring-shaped member respectively disposed inside and around the compression coiled spring, form the damper. Therefore, it is possible to attach the pillar-shaped member and the ring-shaped member to an existing rack-pinion type steering apparatus using in, for example an automobile without changing the compression coiled spring etc. in this apparatus. Thus, this existing rack-pinion type steering apparatus can readily be improved in the ability of restraining the teeth beating noise.
In the above rack-pinion type steering apparatus, the damper is preferably made of a urethane resin.
In this case, the propagation of the teeth beating noise can be restrained more efficiently because the damper is made of the urethane resin.
In the above rack-pinion type steering apparatus, a belleville spring is preferably interposed between the opposite end surfaces of the support yoke and the yoke plug.
In this case, the belleville spring securely receives the support yoke which tends to swing at an angle with respect to the axial direction of the support yoke housing hole, thus restraining the support yoke from swinging.
In the above rack-pinion type steering apparatus, a metal sheet is preferably interposed between the rack shaft and the support yoke.
In this case, the metal sheet improves the heat-resistant properties and the wear-resistant properties for the rack shaft because the support yoke is not directly rubbed with the rack shaft. Accordingly, even though a high load is exerted to the support yoke from the rack shaft, the support yoke can support the rack shaft without the metal sheet being deformed or molten.


A method of treating hydrogen sulfide or producing hydrogen which comprises disposing a liquid tank having a photocatalyst electrode comprising a photocatalyst and a liquid tank having a metal electrode so that the two liquid tanks are separated from each other by a cation-exchange membrane, placing a liquid containing either hydrogen sulfide or an organic substance in the liquid tank having the photocatalyst electrode, electrically connecting the photocatalyst electrode to the metal electrode, and exposing the photocatalyst to a light. The liquid to be placed in the liquid tank having the metal electrode preferably is an acidic solution. The photocatalyst preferably comprises a metal sulfide, and preferably is fine particles having a layered nanocapsule structure.

Applications of photocatalyst techniques have come to be practically used while taking advantage of the property of accelerating various chemical reactions including the decomposition of environmental pollutants, malodorous components/various germs, etc. Examples thereof include antibacterial tiles for use in operating rooms in hospitals, filters for air cleaners and air conditioners, and glasses for, e.g., the lighting of expressways or the like. Besides such practical uses where the oxidation-accelerating ability of photocatalysts is utilized, investigations are being made for the purpose of causing a photocatalyst to act on water or the like to obtain hydrogen or to act on carbon dioxide to fix/reduce the carbon.
On the other hand, from the standpoints of the impoverishment of fossil energy resources and environmental issues such as air pollution caused by global warming, there is a desire for the establishment of a technique for obtaining a clean and safe energy and a cleaning technique for treating environmental pollutants. Of such techniques, use of a photocatalyst is promising. For example, application of a photocatalyst to the step of desulfurizing a crude oil or to a desulfurization step in metal refining may be promising.
The step of crude-oil desulfurization presently in general use is as follows. When a crude oil is distilled, the heavy naphtha is subjected to hydrofining, whereby all the sulfur ingredients contained in the crude oil are converted to hydrogen sulfide and recovered. This hydrogen sulfide is treated by the process called the Claus process and recovered through sulfur oxidation. The Claus process is a process in which one-third of the hydrogen sulfide is oxidized to sulfur dioxide and this sulfur dioxide is reacted with the remaining hydrogen sulfide to obtain elemental sulfur.
This process necessitates a huge amount of energy because heating and condensation are repeated besides the catalytic reaction of sulfur dioxide with hydrogen sulfide. It further has problems, for example, that the management of sulfur dioxide is costly. If a method which comprises adding a photocatalyst to an aqueous alkali solution containing hydrogen sulfide dissolved therein, irradiating the photocatalyst to a light to cause it to absorb the energy of the incident light and generate free electrons and free holes, and oxidizing/reducing the aqueous alkali solution containing dissolved hydrogen sulfide with the free electrons and free holes to obtain hydrogen and sulfur, i.e., a method in which hydrogen sulfide is decomposed with a photocatalyst to generate hydrogen and sulfur, can be put to practical use, then it becomes possible to decompose hydrogen sulfide, which is a hazardous substance, and produce hydrogen and sulfur, which are useful substances, using a smaller amount of energy. Namely, this contributes to the resolution of an environmental issue and enables the production of useful substances.
On the other hand, with respect to the generation of hydrogen by electrolysis, the process in which water is electrolyzed by means of the electromotive force of solar cells is being conducted. In this process, however, the efficiency of electrolysis is governed by the performance of the solar cells. There has hence been a problem that since the devices constituting high-performance solar cells are high-purity high-quality devices, such solar cells are expensive.
In this respect also, if a method in which water is decomposed with a photocatalyst to generate hydrogen can be put to practical use, it becomes possible to produce hydrogen with a smaller energy amount at a lower cost.
However, photocatalysts heretofore in use have had the following problems to be overcome. First, their catalytic activity is low. Secondly, the photocatalysts are toxic. Although photocatalysts generate free electrons and free holes upon irradiation with a light, it is highly probable that these free electrons and free holes recombine. Furthermore, there also is a high possibility that a chemical substance which has been decomposed by an oxidation/reduction reaction might undergo recombination and return to the original compound. Low catalytic activity hence results. Thirdly, the catalysts have a short life. Although the catalysts generate free electrons and free holes upon irradiation with a light, the catalysts themselves are oxidized/reduced, besides a target chemical substance, due to the strong oxidation/reduction reactions caused by the free electrons and holes. Namely, there is a problem of photodissolution that the catalysts thus dissolve away and lose their catalytic activity.
In order to overcome those problems, patent document 1 discloses a photocatalyst having high catalytic activity, no toxicity, and a long life. There is a statement therein to the effect that those three problems have been eliminated.
Also known is a method of treating hydrogen sulfide or method of producing hydrogen in which a stratified-structure electrode comprising a photocatalyst activated with a metal is used.    Patent Document 1: JP-A-2001-190964

Method of treating hydrogen sulfide, method of producing hydrogen, and photocatalytic-reaction apparatus


The invention purpose is a process to obtain gel to elaborate Zeolite 4A, to be used in detergents due to its capacity for calcium absortion; the process lies on the obtention of an alkaline aluminum solution starting from bauxite provided by tank 3 which is attacked in digestor 1 with sodium hydroxide provided by tank 4, with a concentration of 11% minimum, with a filtration of the reacting mass and a purification 13 before the gel formation step in whose reactor 14 is also introduced an alkaline solution of SiO2 to obtain by agitation and temperature a gel which is treated in a crystallizer 15, cooling and concentrating the crystalline mass in 16, filtered in 17, and passed to a dryer 20 from where the product Zeolite 4A passes to storage 21. Bauxite residues are attacked with boiling sulphuric acid in reactor 9, filtering the resulting mass in 11 to recycle the silica and to recover the metal sulphates in solution for using them in water treatments.

The processes known until now to obtain Zeolite 4A do not mention the bauxite as an aluminium source. The manufacture of Zeolite 4A starting from bauxite has several inconvenients in the crystallization step and in the color and purity of the final product, and also in the generation of contaminant residues. With the technology described in this invention, all these inconvenients are avoided, obtaining an optimum product for the manufacture of detergents. Moreover, the substitution of alumina trihydrate by bauxite, which is cheaper, and the possibility of its digestion at atmospheric pressure, notably reduces the manufacturing costs of Zeolite 4A.

Process to obtain zeolite 4A starting from bauxite


This invention relates to preparation of polyamide-imide foam by extruding foamable composition comprising polyamide-imide and volatiles into a confined expansion zone, expanding the composition therein and cooling the result. The resulting foams are essentially open-celled and exhibit good strength, insulating properties and other desirable features.

Polyamide-imides are thermoplastic, high performance, engineering polymers finding use in many applications, such as adhesives, coatings, filled and unfilled molding compositions, fibers, films, composites, laminates, etc., owing to a desirable combination of mechanical strength, heat resistance, chemical inertness and other properties. Torlon.RTM.polyamide-imides, available from Amoco Performance Products, Inc., of Ridgefield, Conn., are examples of commercial polyamide-imides.
It is known that volatiles, such as water and carbon dioxide, generated due to condensation, imidization and other reactions that occur in preparation, molding or other high temperature processing of polyimides or polyamide-imides, including their polyamide-amic acid precursors, or water vapor given off during such processing due to moisture absorbed by such polymers, can cause foaming. As a result, while seldom desired or intentionally produced, polyamide-imides of cellular structure have long been known and observed in various stages of polyamide-imide preparation and processing.
For example, it has been known for several years that polyamide-imides can foam when purged from the nozzle of the injection barrel of an injection molding machine. Published technical information related to Torlon.RTM.engineering resins, Amoco Chemicals Corporation Bulletin TAT-la, discloses that in setting up for injection molding of such materials, purge shots should be examined for excessive foaming and that if the same occurs the material should be redried for 8-24 hours at 350.degree. F. Injection molded parts with a cellular structure also can result when the amount of polymer injected into a mold is insufficient to fill it or, as disclosed in the above-mentioned Bulletin TAT-la, when mold closed time is too short. It also is well known that polyamide-imide parts prepared by extrusion may have voids.
While neither intended nor particularly desirable, it also is known that commercially available polyamide-imide pellets, generally having lengths and diameters up to about one-half inch (about 1.3 cm), can sometimes exhibit irregular cellular structures and densities below those of solid polymer. Pellets usually are prepared by plasticating polymer flake or powder using a screw conveyor, extruding the plasticated polymer through a strand die, continually removing strands of extrudate from the die, cooling the strands and chopping the cooled strands into pellets. When the softened extrudate exits the die, expansion of the strand due to volatiles liberated during plastication may result in formation of a cellular structure unless the strand is cooled sufficiently rapidly after exiting the die to prevent expansion. Of course, it is desirable to maximize pellet density to maximize throughput of resin and minimize packaging, shipping and other downstream handling and processing of gas(es) present in any cellular material. Accordingly, such efforts as are intentionally directed to controlling density in such pelletizing operations aim to maximize density and, thus, minimize foaming.
Commonly assigned U.S. Pat. No. 4,581,264 to Emery et al., issued Apr. 8, 1986, teaches that in production of articles of manufacture by extrusion of compositions comprising polyamide-imide, introducing air and moisture into the extrusion system is undesirable because articles that are foamed or have porosity can result. Emery et al. also teaches that use of a single-screw extruder is undesirable because parts having porosity can result.
Other examples of polyamide-imides having foamed or cellular structures are described in commonly assigned U.S. Pat. No. 4,167,620 to Chen, issued Sept. 11, 1979, directed to heat treating shaped articles comprising polyamide-imide to avoid foaming, distortion and sacrifices in properties resulting from thermal shock. Without such treatment, thermally shocked articles exhibit irregularly sized voids or cells, often distributed randomly throughout the articles. Blisters may be present on the surfaces of such articles. Physical properties generally are poor and frequently nonuniform throughout the articles. Chen is directed to preventing void formation and other deleterious results of thermal shock by heat treating polyamide-imide shaped articles to drive off volatiles without substantial distortion, formation of voids and other adverse effects. Commonly assigned U.S. Pat. No. 4,403,061 to Brooks et al., issued Sept. 6, 1983, avoids such undesirable effects, while reducing requirements for heat treatment, by adding to polyamide-imides metal oxides capable of tying up water that otherwise might contribute to foaming, distortion and other sacrifices.
As is known, polyamide-imide foams obtained as described above exhibit irregular, open-cell structure. Interconnected, randomly sized and shaped voids often vary in size, shape and distribution from one area of a foam to another. Such nonuniformity is hardly surprising given that foaming usually takes place only inadvertently, with efforts related to foaming being directed toward avoiding, rather than promoting, the same.
Polyamide-imide foams also have been produced intentionally. For example, foamed rods and boards of Torlon.RTM.polyamide-imide prepared by extrusion using circular and sheet dies, respectively, and without rapid cooling of extrudate but otherwise similar to the above-described pelletizing procedure exhibit useful cell structure and other properties although control over foaming is limited. Satisfactory foam structure and properties also have been obtained by heating commercial Torlon.RTM.polyamide-imide powder or pellets in a closed mold to above glass transition temperatures ("Tg") of the polymers, generally at about 65.degree. to about 200.degree. C. above Tg, for a time sufficient to soften and fuse the particles and cause absorbed and evolved volatiles to expand the polymer to fill the mold. Residence times in the mold can range from several minutes to several hours, with time and temperature being adjusted to achieve suitable softening, fusion and expansion without charring the surface of the final product. After heating, the mold is cooled to below Tg whereby the expanded cellular mass solidifies and a foamed shape conforming to the mold cavity is removed. Foaming of polyamide-imides by such a technique, sometimes referred to as confined free rise or confined free expansion foaming, is employed for fabrication of shaped articles of simple geometry such as panels, sheets and blocks.
Foamed polyamide-imides prepared by extrusion and confined free rise as described above have densities generally ranging from about 15 to about 50% of those of the unfoamed, starting polyamide-imides. In the case of Torlon.RTM.polyamide-imides having unfoamed densities of about 1.4 g/cm.sup.3, foam densities of about 0.2 to about 0.7 g/cm.sup.3 (about 15-40 lb/ft.sup.3) are commonly achieved by confined free rise foaming. The foams have a substantially open-cell structure of interconnected cells, generally of about 0.05 to about 0.5 inch (about 0.12-1.3 cm) diameter, compressive strengths of about 250 to about 800 psi (about 17-56 kg/cm.sup.2), and K factor, indicative of thermal insulation and decreasing with decreasing density, of about 0.4 to about 1.2 btu in/ft.sup.2 hr .degree. F. (about 1.38 .times.10.sup.-4 -4.13 .times.10 .sup.4 cal/sec cm .degree. C.). The foams char when exposed to flame, extinguishing on removal thereof. Screw fastener retention is sufficient to permit attachment with screws to or between other materials, e.g., metal, wood, concrete or foamed or unfoamed synthetic materials, or in a sandwich-type structure having such other materials between layers comprising polyamide-imide foam.
While such intentionally foamed polyamide-imides can exhibit useful properties, preparation thereof as described above suffers from poor control over foaming in the case of extrusion and is time-consuming and limited by mold and oven size and to shapes of simple geometry in the case of confined free rise foaming. Further, for a given polymer composition to be foamed by heating in a closed mold, variations in particle size of the particulate polymer placed in the mold can have a significant effect on process conditions required to achieve useful properties or on properties themselves. Larger particles retard diffusion of volatiles out of the mass of particles as it is heated to soften and fuse the same; if heating is too severe, for example, at too high a temperature or for too long a time, formation of char or large, irregular voids can result. Conversely, with smaller particles, heating at too low a temperature or too slowly can result in insufficient foaming due to loss of volatiles by diffusion prior to softening and fusing of the polymer.
Polyamide-imide foams also have been prepared intentionally by so-called short-shot injection techniques in which an amount of softened, fused polymer effective to yield a desired density without filling a mold is injected into the mold. Polymer in powdered or pellet form is introduced into a hopper and conveyed by a screw conveyor through a heated barrel of an injection press or like apparatus. As the polymer proceeds along the length of the barrel it softens, the softened particles fuse and volatiles are generated. Foaming of polymer in the barrel is substantially prevented by maintaining suitable back pressure within the barrel. A shut-off nozzle is used to maintain a melt seal in the barrel, preventing undesirable nozzle foaming prior to injection. From the exit end of the barrel the polymer and volatiles are forced into the mold, the amount injected and, in turn, density of the foam being prepared, being controlled by the length of the injection stroke. An example of a suitable injection press is a Natco 500 ton injection molding machine available from Natco Corporation. After rapid expansion of the foamable composition in the mold, the resulting expanded composition is cooled to below Tg and a foam with an outer skin of solid, unfoamed or essentially solid polyamide-imide is removed from the mold. Although more complex shapes can be prepared by short shot injection foaming than by confined free rise expansion, the former is expensive and limited to parts of higher densities than in confined free rise unless carried out with a heated mold which adds additional expense.
Polyamide-imide foams prepared by short shot injection foaming, like those prepared by confined free expansion, are of open cell structure, generally with cells of similar size and shape. Torlon.RTM.polyamide-imide foams prepared by short shot injection foaming typically have densities of about 0.5 to 0.6 g/cm.sup.3.
While not directed to solving problems encountered in such prior art methods, the following patents may be of interest in connection with this invention in disclosing various foams prepared by techniques in which volatiles generated during processing contribute to foaming
U.S. Pat. No. 4,394,664 to Gagliani et al., issued July 19, 1983, discloses foams prepared by reacting pyromellitic dianhydride or 3,3',4,4'-benzophenone tetracarboxylic acid dianhydride and certain oxoimines, esterifying the result, reacting the esterification product with diamine, drying the result to a free-flowing powder or flake and then heating to imidize and condense with liberation of alcohol and water which expand the polymer to a self-supporting cellular structure. Preparation of foamed sheets by heating such polymers in an oven is disclosed in the examples. U.S. Pat. No. 4,426,463 to Gagliani et al., issued Jan. 17, 1984, discloses foams of increased compressive strength prepared similarly but at reduced oxoimine-to-dianhydride ratios and U.S. Pat. No. 4,539,336 to Long et al., issued Sept. 3, 1985, discloses a related preparation in which dianhydride and oxoimine are reacted in alcohol.
From commonly assigned U.S. Pat. No. 3,300,420 to Frey, issued Jan. 24, 1967, it is known to prepare foamed plastics or dense molding resins, depending on reaction conditions, by reaction of trimellitic anhydride and aryl polyisocyanates with liberation of carbon dioxide. According to the patent, carrying the reaction to completion with minimum confinement of polymer results in foam of excellent cell structure and physical properties.
U.S. Pat. No. 3,483,144 to Lavin et al., issued Dec. 9, 1969, discloses in situ preparation of polyimide foams by mixing tetracarboxylic acid and polyamine to form a system with volatiles content of at least 6.2% and heating to simultaneously polymerize and foam. Foaming is said to occur due to volatilization of solvent used in preparation and water vapor evolved from condensation reactions.
U.S. Pat. No. 3,926,911 issued Dec. 16, 1975, and U. S. Pat. No. 3,948,835 issued Apr. 6, 1976, both to Greber et al., disclose silicon-modified polyamides, polyamide-imides or polyimides prepared from polycarboxylic acid compounds and aminosilanes. Use of the polymers to form foams and heating of prepolymer powder in a closed mold to produce hard foam of uniform pore size are disclosed.
While the foregoing disclose certain foams and that residual solvents or reaction by-products, such as water vapor, cause or contribute to foaming, the disclosed foams are prepared in situ during polymerization or by a confined free-rise technique as described above, i.e., by heating in a closed mold. These patents do not address the problems of long processing times, part size/shape limitations, particle size effects or process complexity and expense.
Also of possible interest in connection with this invention is Modern Plastics Encyclopedia, Vol. 54 No. 10A (1977-1978), pp. 294-302, discussing generally various types of conventional thermoplastic foams and production thereof, including profile extrusion with vacuum sizers or sizing dies and structural foam molding. Foaming of polyamide-imides and problems associated with control of foaming of such resins due to volatiles evolved during heating of the same are not addressed.
As can be appreciated, there is a need for a process for manufacture of polyamide-imide foams having useful properties at greater production rates than previously achieved with greater flexibility as to part size.
It is an object of this invention to provide such a process. A further object is to provide a continuous process for preparing polyamide-imide foams. A further object is to provide a method for producing high strength, foam comprising polyamide-imide having utility in applications such as automotive or aerospace insulation materials and firewalls. A still further object is to provide for production of polyamide-imide foam parts with flexibility as to part size and geometry and at greater production rates with better control over foaming than offered by known techniques.
We have found that the objects of this invention can be achieved by extruding a foamable composition comprising softened, fused polyamide-imide and volatiles into a confined expansion zone, expanding the foamable composition in the confined expansion zone and cooling the expanded composition. Advantageously, foam density is easily controlled and foam parts of large or small size can be prepared. Further, the process can be conducted continuously, and with good control over foaming, thereby offering advantages over known techniques in terms of process speed and reliability. Further, particle size effects encountered in confined free-rise foaming are eliminated in the invented process by softening and fusing a foamable composition comprising polyamide-imide and volatiles before introduction of the composition into a confined expansion zone. The invented process is more flexible as to part size and density than short shot injection foaming. Further, other things being equal, the invented process offers advantages as to production rates because parts are prepared by an extrusion process which allows for production of parts that are continuous in one dimension, as opposed to the closed molds used in both short shot injection foaming and confined free expansion. Foams comprising polyamide-imide prepared according to the present invention, like those prepared by known techniques, exhibit a desirable combination of density, structural strength, insulating and other properties. The foams have a substantially open cell structure with cell sizes and shapes being comparable to those of known, intentionally prepared polyamide-imide foams. As prepared, the foams usually are encased within essentially continuous polyamide-imide skins, the densities of which equal or approach those of the solid, unfoamed polyamide-imide composition used in the invented process at the surface of the foamed part and decrease toward its interior. Such skins, while providing extra strength, can be removed easily if desired. The skins may have utility as regrind polymer in the invented process.

Process for preparing polyamide-imide foam


A calculator system with visual and speech outputs uses a single monolithic LSI chip which includes: a single ROM containing program instructions for both system and speech control, as well as data for synthesizing speech; a central controller which calculates both inputted data and program execution data to control the system, and a RAM used by the central controller in manipulating data.

The present invention relates to an integrated circuit for generation of sound by means of an electronic apparatus, and in particular to a large scale integrated circuit (LSI) for an electronic apparatus by which the input and output of sound may be obtained synthetic speech generated, and which also includes key input/output apparatus and display apparatus.
In recent years, television games in which the sound of cannons is heard, electronic calculators and timepieces which play melodies, pocket learning devices and electronic calculators which emit human voices, automatic vending machines, and other types of electronic apparatus which emit sounds have made their appearances one after the other. These types of products have been, in part, responsible for the development of LSI technology and in the furthering of synthetic speech generation techniques.
A synthetic speech apparatus used in electronic equipment for sound generation is basically of the type shown in FIG. 1, which is comprised of a ROM 1, in which voice data is stored, and a speech synthesizing circuit 2 which synthesizes a voice signal from this data, with a control circuit 3 which controls the starting and stopping of the synthesizing procedure and the readout from ROM 1. The speech synthesizing circuit 2, from a general point of view, is usually made up of a special synthetic speech LSI, which is used as one of the parts of the speech synthesizing section of this synthetic speech apparatus. Therefore, in the case where this LSI comprises, for example, an element of an electronic calculator which converts calculated formulas, and results, into information in the form of speech (FIG. 2), a microprocessor 4 generally controls the primary key input, the operation, and the display, and this microprocessor develops information in the form of speech from the instruction signal to be provided a specialized speech synthesizing LSI 2.
However, considering the scale of apparatus involved in speech generating electronic calculators and timepieces from the aspect of the configuration of the whole system, the circuit includes a relatively large device portion devoted to speech synthesis as compared with the primary function control circuit. There is considerable demand for a miniaturized compact unit, such as a speech generating electronic calculator which is small enough to be held in the palm of the hand.

One chip integrated circuit for electronic apparatus with means for generating sound messages


Disclosed are an apparatus and method of remotely communicating with a managed machine. One example method of operation may include selecting the managed machine operating in a communication network, transmitting a connection request message to the managed machine and establishing a secure connection between the managed machine and an administrator machine. The example method may also include responsive to connecting with the managed machine, executing a host service on the managed machine, and connecting to the host service over the communication network via an application client operating on the administrator machine.

User workstations or managed machines (computing devices) operate in a data communication network by communicating with other managed machines and/or administrator machines. Regardless of the status of the machine, the administrator machines operate to support ongoing communications and applications operating on the managed machines.
Accessing and executing commands on a managed machine through an administrative interface is a common method of updating, controlling, debugging and ensuring the continued seamless operation of the managed machine. However, certain challenges are presented with the advent of varying operating systems, control interfaces and other commonalities of the managed machines operating on a data communication network. For example, various applications used by administrators to manage network computing devices often rely on a web-based browser application to engage the administrator with certain options and simple execution of administrative actions. In addition, feedback communications between the administrator machine and the managed machine(s) may require a secure connection and other communication features prior to authorizing administrative access to managed machines.

This patent is subject to a terminal disclaimer.

Method and apparatus of performing remote management of a managed machine


A liquid starting mixture contains at least one fatty acid having 6 to 30 carbon atoms per molecule and per mole of fatty acid comprises 1.0 to 1.5 moles of fatty alcohol having 6 to 30 carbon atoms. An intermediate product which contains at least 50% by weight is prepared from the liquid starting product, which is passed at temperatures from about 120 to 320.degree. C. through a stirring zone and is sprayed and water vapor is removed. The intermediate product is hydrogenated to produce a raw product, which contains at least 75% by weight fatty alcohol. A partial stream which contains fatty alcohol is removed from the raw product and is added to the liquid starting mixture. The intermediate product which contains at least 50% by weight wax ester can be prepared without use of a solids containing catalyst.

German Patent 28 53 990 and the corresponding U.S. Pat. No. 4,259,536 disclose the preparation of fatty alcohols by a catalytic hydrogenation of fatty acids in the liquid phase. From German patent document DE-A-39 13 387 it is known to catalytically hydrogenate liquid fatty acid methyl esters and to prepare a mixture of fatty alcohols and methanol.

Process for preparing wax esters and hydrogenation of wax esters to fatty alcohols


A method of performing a dynamic built-in self-test (BIST). The method includes performing a first test of a circuit on a semiconductor chip. The first test includes a first switch factor. The circuit during the first test is monitored with one or more sensors. A first sensor value of one or more sensors monitoring the circuit is determined. It is also determined whether the first sensor value is within a range of a programmable constant. A second switch factor is determined in response to determining that the first sensor value outside the range of the programmable constant.

Digital Integrated Circuits (ICs) can be prone to defects introduced during a manufacturing process. These defects may affect the logic output of the digital IC, which in turn adversely influences semiconductor chip quality and costs. Industry has developed a number of testing techniques to test for the defects. To test for defects, a built-in self-test (BIST) may be built into an IC, allowing the IC to test its own operations. BISTs may be implemented using hardware, software, or a combination of the two.

International Business Machines Corporation


The present invention relates to signal processing in an optical receiver, in particular to equalization performed in coherent optical receivers. A multiple-input multiple-output (MIMO) equalizer receives and equalizes a plurality of real value signals, for example four sampled electrical baseband tributaries (HI, HQ, VI, VQ). The outputs of the multiple-input multiple-output (MIMO) equalizer provide equalized real or imaginary components of complex signals. The complex signals including the real and imaginary components are then each and individually equalized to remove chromatic dispersion.

Conventional coherent receivers in optical communication systems make use of channel equalizers to mitigate channel impairments. For example, equalizer stages can be implemented to provide a digital detector with the capability to correct channel impairments.
In this respect, modern optical communication systems can employ multi-phase multi-level signal alphabets and polarization division multiplexing (PDM) to carry high data rates with good spectral efficiency. In contrast to traditional direct demodulation, state-of-the-art coherent demodulation techniques map the impinging optical signal onto electrical signals potentially without any loss of information.
Signal processing in coherent optical receivers is customarily implemented in the equivalent complex baseband. The receiver front-end decomposes an arbitrary pair of orthogonal polarizations H and V into their in-phase (I) and quadrature (Q) components. The four resulting electrical signals HI, HQ, VI and VQ are sampled and passed to a digital processor that implements the detection algorithms.
Typical processing entails multiple stages for the mitigation of the transmission impairments. The group velocity dispersion (GVD) induced by chromatic dispersion (CD) in optic fibers can, for example, be compensated via a linear equalizer called bulk CD equalizer. Since CD acts independently of the polarization and is a quasi-static phenomenon, the bulk CD equalizers processes the H and V polarizations separately and it is generally sufficient to adjust the CD equalizers only at link set-up or in case of link reconfiguration.
By contrast, polarization dependent effects occurring in the optical fiber, such as for example polarization rotation, polarization mode dispersion (PMD) and polarization-dependent loss (PDL), are more dynamic in nature. These effects are conventionally compensated using a second linear equalizer, called multiple-input multiple-output (MIMO) equalizer, which processes jointly the H and V signals. Because of the dynamic nature of the polarization dependent effects, the MIMO equalizer can be continuously adapted to react to dynamically changing channel conditions.
Following the equalization stages, additional detection stages can include carrier frequency and phase recovery, which compensates the mismatch between transmit and receive lasers.
FIG. 1 shows a representation of digital signal processing device 100 included in a conventional coherent receiver.
The four electrical baseband tributaries (HI, HQ, VI, VQ) 110, 120, 130, 140 correspond to H and V polarizations of an optical signal, transmitted via an optical fiber, which have been received and converted to electrical baseband tributaries at the coherent receiver. In FIG. 1, the four electrical baseband tributaries (HI, HQ, VI, VQ) 110, 120, 130, 140 are sampled at Nyquist rate or faster by means of four analog-to-digital converters (ADCs) 150, 160, 170, 180. It follows that a timing misalignment (skew) among the electrical baseband tributaries (HI, HQ, VI, VQ) 110, 120, 130, 140 can arise as a consequence of imbalances in the analog paths, such as for example in the analog-to-digital converters (ADCs) 150, 160, 170, 180. The sampled signals are forwarded to configurable delays 190, 200, 210, 220, described in more detail below, and the I and Q components of both polarization planes are logically gathered in two complex signals corresponding to H and V in the equivalent complex baseband. In FIG. 1, the step of gathering the I and Q components of each polarization plane is symbolized by having multiplier blocks 230, 240 perform multiplication of the Q components by the imaginary unit j, and by a subsequent addition of the respective real and imaginary parts.
Then, each polarization plane of the complex baseband signal is passed through a complex-valued single-input single-output (SISO) bulk CD equalizer 250, 260. Here, the bulk CD equalizer 250, 260 typically corresponds to a long linear finite impulse response (FIR) filter, for example with up to 4000 complex coefficients. Due to complexity reasons, the bulk CD equalizer 250, 260 FIR filter can be implemented in the frequency domain.
Both polarization signals provided by the bulk CD equalizers 250, 260 are then jointly processed by a MIMO equalizer 270. In this example, the MIMO equalizer 270 includes a 2×2 FIR decimating filter with up to ˜40 taps (time delays) with adaptive complex coefficients. At the outputs of the MIMO equalizer 270, two complex signals are provided with one sample per symbol. The MIMO equalizer 270 is typically realized in the time domain, although an equivalent frequency-domain implementation can also be used.
In the example shown in FIG. 1, a carrier recovery block 280 computes and applies a phase correction to the signals provided by the MIMO equalizer 270. The phase corrected H and V signals 290, 300 are subsequently de-mapped in a demapper 310 to hard-decided bits in case of hard-decision forward error correction (FEC), or soft bit metrics in case of soft-decision FEC. The output of the demapper 310 can then be provided to a channel decoder 320 for further processing.
FIG. 1 shows a conventional solution for the blind adaptation (without dedicated training symbols) of the MIMO equalizer 270. In this scheme, mismatch errors are estimated in mismatch error estimation blocks 330, 340, 350, 360 based on signals provided by the MIMO equalizer 270, either before or after the carrier recovery 280 has processed the signals. The estimated mismatch errors are then used to adapt the coefficients of the MIMO equalizer 270. For this purpose, selection blocks 370, 380 can be provided to select or merge signals for adapting the coefficients of the MIMO equalizer 270 based on the mismatch errors provided by the mismatch error estimation blocks 330, 340, 350, 360. In the example shown in FIG. 1, the mismatch errors received by the selection blocks 370, 380 can be preprocessed in phase shifting complex conjugating blocks 390, 400.
Typical error criteria derived before phase correction (within the mismatch error estimation blocks 330, 340 shown in FIG. 1) are the stop-and-go algorithm, the constant modulus algorithm (CMA) or modifications thereof. After phase correction, the mismatch is computed (within the mismatch error estimation blocks 350, 360 shown in FIG. 1) as the difference between the received samples and the next valid respective constellation symbols, which is known as decision-directed least-mean-square (DD-LMS) algorithm; in this case the error is counter-rotated (within the blocks 390, 400) by the opposite of the carrier phase correction before being passed to the equalizer.
In some implementations, the receiver can initially rely upon an error computed before the carrier recovery, before it switches to a more accurate criterion derived after the phase correction as soon as the carrier recovery converges.
As mentioned above, a timing misalignment (skew) among the electrical baseband tributaries (HI, HQ, VI, VQ) 110, 120, 130, 140 can arise as a consequence of imbalances in the analog paths, such as for example in the analog-to-digital converters (ADCs) 150, 16, 170, 180. Such imperfections in the analog front-end and in the sampling devices 150, 16, 170, 180 impair the quality of the complex baseband signals. In particular, imbalances in the length of the receiver paths result in timing misalignments (skew) between HI and HQ or VI and VQ, which can severely degrade the performance of the receiver when using high-order modulation formats. Skew between homologous H and V components is less critical because it is akin in its effect to polarization mode dispersion (PMD) and can thus be seamlessly compensated by the MIMO equalizer 270.
FIG. 2 shows a penalty chart 500, wherein the penalty caused by the above timing misalignment (skew) is illustrated in terms of optical signal-to-noise ratio (OSNR) 510 for several m-ary quadrature amplitude modulation (mQAM) formats 520 (at a bit-error rate (BER) of 10−3) as a function of a normalized IQ-skew 530. The penalty indicates the increase of OSNR required to keep the BER at a defined level (10−3 in the example) due to the signal distortions as compared with undistorted signals. For example, in order to stay below a maximum penalty of 0.5 dB, the skew must be maintained below 11%, 5% and 3% of the signaling period for the illustrated 4QAM, 16QAM and 64QAM modulation formats, respectively. This represents a challenging requirement at typical signaling rates of 30-35 GHz for any constellations larger than 4QAM. Additionally, the emerging trend towards higher symbol rates is going to exacerbate the problem.
A precise design of the analog circuitry can suffice to maintain the IQ skew below certain thresholds, and can, for example, provide a feasible solution for PDM-4QAM systems running at an information bit rate of ˜100 Gb/s. However, such precision dependent analog circuitry design becomes increasingly prohibitive as the constellation size and the signaling rate grow. Moreover, it is difficult, if not impossible, to predict skew effects arising in such ADCs, which further complicates the analog circuitry design, and can even prevent the appropriate dimensioning of strip lines on the printed circuit board.
A different state-of-the-art approach aims at mitigating the problem using a calibration procedure. Digital samples are captured directly after the ADCs 15, 160, 170, 180 shown in FIG. 1 and are used to measure the skew. Then, the programmable delays 190, 200, 210, 220 are adjusted accordingly in order to compensate for the timing misalignment. In this approach, the configurable delays 190, 200, 210, 220 must be able to shift the digital signal by fractions of the sampling period, for example by interpolating between the samples. A significant disadvantage of this approach is that the respective calibration routine can be time-consuming and dedicated components (capture facility after the ADCs and configurable fractional delays) are required, which increases the complexity of the circuit and digital processor, and also increases the related power consumption. Further, this approach provides a fixed, non-adaptive, compensation, which can be inadequate for many demanding modulation formats. For example, if the skew of the analog circuitry is time-varying, e.g. because of temperature effects, and/or the skew of the ADCs can change at each power cycle, an adaptive compensation is preferred.
The paper "Compensation for In-Phase/Quadrature Imbalance in Coherent-Receiver Front End for Optical Quadrature Amplitude Modulation" by Md. S. Faruk and K. Kikuchi, IEEE Photonics Journal, volume 5, Number 2, April 2013, shows that the MIMO equalizer in the digital signal processing device 600 can be modified as shown in FIG. 3 to adjust any imbalance, including skew, between the I and Q channels. For this purpose, the paper proposes replacing each of four complex-valued FIR filters included within the complex-valued 2×2 MIMO equalizer 270 shown in FIG. 1 with a 2×2 real-valued MIMO equalizer. As a result, the standard complex 2×2 MIMO equalizer 270 is replaced by a real 4×4 MIMO equalizer 610 as shown in FIG. 3, which has separate ports for HI, HQ, VI and VQ signal components provided by Re/Im splitting blocks 620, 630. Differently from a complex equalizer, a real equalizer processes the real and imaginary parts of H and V as distinct signals and can delay them by different time offsets, thereby correcting IQ skew. As shown in FIG. 3, the so filtered real and imaginary parts of each polarization plane are symbolized conceptually for illustration purposes by having multiplier blocks 640 multiply the respective Q components by the imaginary unit j and the subsequent addition of the respective real and imaginary parts. The paper by Faruk and Kikuchi states that any standard adaptation algorithm can be adopted to update the coefficients of the real MIMO equalizer, and the DD-LMS algorithm is further demonstrated in the paper. Also in this respect, since a complex multiplication requires (in a typical realization) four real multiplications and two real additions, the computational burden of a real 4×4 filter is equivalent in terms of the underlying real arithmetic to that of a complex 2×2 filter.
The paper "Blind Equalization of Receiver In-Phase/Quadrature Skew in the Presence of Nyquist Filtering" by M. Paskov, D. Lavery and S. J. Savory, IEEE Photonics Technology Letters, volume 25, number 24 on Dec. 15, 2013, follows a similar approach as proposed by Faruk and Kikuchi, see discussion above and FIG. 3, but suggests computing the error criterion used for MIMO equalizer 610 adaptation before the carrier recovery, adopting the constant modulus algorithm (CMA) for 4QAM and a radially directed equalizer algorithm for higher order QAM.
The limitations of the above approaches proposed by Faruk and Kikuchi and by Paskov, Lavery and Savory are discussed in the following two papers authored by R. Rios-Müller, J. Renaudier and G. Charlet: "Blind Receiver Skew Compensation for Long-Haul Non-Dispersion Managed Systems", European Conference on Optical Communications in Cannes, France, September 2014 and "Blind Receiver Skew Compensation and Estimation for Long-Haul Non-Dispersion Managed Systems Using Adaptive Equalizer", Journal of Lightwave Technology, volume 33, number 7, April 2015. As explained in these papers, the receiver of FIG. 3 can effectively correct IQ skew arising in the receiver front-end only in the back-to-back configuration. In other words, as soon as the signal is transmitted over an optical link, it experiences GVD that must be compensated in the bulk CD equalizer. In this case, the complex coefficients of the bulk CD equalizers 250, 260 shown in FIG. 3 mix the I and Q components on each polarization plane. It follows that the subsequent real 4×4 MIMO equalizer 610 is prevented from accessing and delaying independently the I and Q components on each polarization plane.
From a mathematical perspective, unifying the bulk CD equalizers 250, 260 and the MIMO equalizer 610 in a single bulk CD MIMO equalization stage seems to provide a feasible solution. In FIG. 3, this corresponds to the removal of the blocks enclosed in the dashed rectangle 650. However, merging both equalization stages into one stage requires the implementation of an adaptive MIMO equalizer including 500-4000 (instead of 1-40) taps, which is impractical. On the one side, the adaptation of such a large number of tap coefficients runs into huge convergence difficulties; and on the other side, the use of a 4×4 bulk CD MIMO equalizer results in double complexity with respect to the state-of-the-art solution having two complex 1×1 bulk CD equalizers.
In view of this, Rios-Müller, Renaudier and Charlet propose a different digital signal processing device 700 as illustrated in FIG. 4. The tributaries (HI, HQ, VI, VQ) 110, 120, 130, 140 are separately processed by four bulk CD equalizers 710, 720, 730, 740 with complex coefficients. In FIG. 4 a zero imaginary part is added 750, 760 to each I tributary and the Q tributaries are multiplied 770, 780 by the imaginary unit to indicate for illustration purposes that they are interpreted and processed as a complex signal. Each output of a bulk CD equalizer 710, 720, 730, 740 is complex but contains contributions from only one tributary. Differently from the digital signal processing device 600 shown in FIG. 3, the complex MIMO equalizer 790 shown in FIG. 4 can delay the tributaries independently and correct a relative timing misalignment also in the presence of GVD. The implementation of the four bulk CD equalizers 710, 720, 730, 740 can be simplified by exploiting the fact that the imaginary part of their input is zero. In fact, it is easy to prove that the four bulk CD equalizers 710, 720, 730, 740 of FIG. 4 require approximately as many computations as the two bulk CD equalizers 250, 260, 620, 630 shown in FIG. 1 or FIG. 3.
However, a significant disadvantage of the arrangement shown in FIG. 4 is that the complex 4×2 MIMO equalizer 790 requires twice as many computations as the standard complex 2×2 MIMO equalizer 270 of FIG. 1 or the real 4×4 MIMO equalizer 610 of FIG. 3.

Signal processing in an optical receiver


A Photoelectric sensing array system with daughter boards daisy chained together so that varying size touch systems can be modularly constructed using the same electronics. The system also provides for increased touch resolution.

This invention relates to a photoelectric sensing array system, method and apparatus for a touch input device or touch screen. Touch screens are often used in conjunction with a display as an input device to a computer display, a kiosk display, or other display application. The touch screen device is typically a finger as shown in FIG. 1. Other touch means may be employed such as a pointer, pencil, or other object.
There are different types of touch screens available including infrared, resistive, capacitive, and acoustic wave. This invention relates to infrared touch screens. Infrared touch screens comprise an array of infrared photo emitters, each paired with an array of infrared (IR) photo detectors.
The position of an opaque object located between the transmitting array and the receiving array is determined by individually pulsing the infrared photo emitter sources while electronically sensing the response of the corresponding photo detectors.
The IR prior art discloses arrays that produce a multitude of invisible light beams, whereby corresponding sensors are blocked at the position where an opaque object is located. The center of the opaque object can be determined by electronically sensing current flow in each of the photo sensors, and then computing the center point of the region of blocked photosensors. Commonly this IR detection process is done in two axes simultaneously to create a two dimensional sensing grid such as found on a computer touch screen as shown in FIG. 1.
In the IR prior art, the sensor arrays of this type have the light emitting transmitters mounted on one side and the photo detecting receivers mounted on the opposite side. See U.S. Pat. No. 4,672,364 (Lucas); U.S. Pat. No. 4,841,141 (Ouchi); U.S. Pat. No. 4,891,508 (Campbell); U.S. Pat. No. 4,893,120 (Doering et al); U.S. Pat. No. 4,904,857 (Ando et al); U.S. Pat. No. 4,928,094 (smith); U.S. Pat. No. 5,162,783 (Moreno) and U.S. Pat. No. 5,579,035 (Beiswenger), which are each incorporated herein by reference.
Technical and manufacturing improvements in the production of displays such as LCD, plasma, and rear projection have made available large area displays. Large displays are desirable in applications such as dynamic signage, kiosks, lobby portholes, and games. These large displays require large touch screens to provide a large interactive display surface.
The development and production of large touch screens is complex. Resistive and capacitive touch screens are not easy to fabricate in large sizes due to poor yield. Similarly, acoustic wave attenuates with large touch systems size. Infrared touch screens are more readily scaled to large sizes than other touch system technologies. However, problems such as alignment of sensors, resolution, mean time between failures and manufacturability are magnified with increasing size.


The technology provides for alignment of forming positions of glazing gaskets formed on both front and rear sides of a glass panel. After the glazing gasket has been formed on the multilayer glass panel, a first distance L1 is measured from the reference member to the glazing gasket. After the multilayer glass panel has been reversed and positioned at the reference position for the glass panel, a second distance L1′ is measured from the reference member to the glazing gasket. An offset amount of the forming position of the glazing gasket on the rear side of the multilayer glass panel is determined from the difference of the first distance L1 and the second distance L1′. An application starting position of the application nozzle when forming the glazing gasket on the rear side of the multilayer glass panel is corrected based on the offset amount.

The applicant has already proposed a method of manufacturing a multilayer glass panel with a glazing gasket by ejecting glazing gasket molding material such as a thermoplastic elastomer in a constant shape together with an adhesive from an application nozzle, applying them onto the surface of the glass panel to form the glazing gasket, to install the glazing gasket on the surface of the glass panel with an adhesive (see Japanese Unexamined Patent Application Publication No. 2011-51802).
In this previous application, the glazing gasket molding material and the adhesive are ejected from the application nozzle superimposed in two layers and applied onto the surface of the glass panel.
However, when manufacturing the multilayer glass panel with a glazing gasket as described above, as illustrated in FIG. 1, first, plasticized resin material is extruded from an application nozzle (not illustrated) at a position on a front side peripheral edge of a multilayer glass panel 2 via an adhesive layer so that it is applied along the whole length of the front side peripheral edge of the multilayer glass panel 2, to form a front side glazing gasket 4. Next, the multilayer glass panel 2 is reversed, and plasticized resin material is extruded from the application nozzle (not illustrated) onto a position on a rear side peripheral edge of the multilayer glass panel 2 via the adhesive layer so that it is applied along the whole length of the rear side peripheral edge of the multilayer glass panel 2, to form a rear side glazing gasket 6. In this way, it is possible to manufacture the multilayer glass panel with a glazing gasket.
With such a multilayer glass panel, it is possible to manufacture the multilayer glass panel with a glazing gasket by directly applying the plasticized resin material to the surface of the glass panel, so automation is easy, and it is possible to form the glazing gasket on the surface of the glass panel at high speed, so it is possible to increase the productivity of the multilayer glass panel with a glazing gasket.
However, when applying the resin material on the front side and the rear side of the multiplayer glass panel to form glazing gaskets, each application operation is carried out as a separate process, and moreover, when forming the glazing gasket on the rear side of the multilayer glass panel, the multilayer glass panel is reversed after forming the glazing gasket on the front side, set on a work table with the rear side facing upward, and positioned. In this case, a positional deviation d as illustrated in FIG. 1 will occur between the front side glazing gasket 4 and the rear side glazing gasket 6, due to variation in the accuracy of cutting the glass and the accuracy in bonding the glass together, as well as due to variation in accuracy of positioning the glazing gasket with respect to the multilayer glass panel and variation in operational accuracy of the application device in the process of manufacturing the multilayer glass panel.
Therefore, if, for example, the rear side glazing gasket 6 has deviated to farther inner side than the front side glazing gasket 4, producing a value of deviation d between the two, and this value exceeds the allowable range of the inside dimension of a sash 8, for example, 2 mm, then even though the multilayer glass panel with a glazing gasket 2 is fitted to the sash 8 as illustrated in FIG. 1, the inside dimension of the sash 8 is constant, so a gap occurs between a fitting edge 8a of the sash 8 and a fitting step 4a of the front side glazing gasket 4 or a fitting step 6a of the rear side glazing gasket 6 fitted to the fitting edge 8a. As a result, the water tightness and air tightness of the multilayer glass panel fitted to the sash is damaged.
Also, depending on the size of the deviation between the front side and rear side glazing gaskets, it may not be possible to fit the front side or the rear side glazing gasket to the sash, and, in addition, it may not be possible for the multilayer glass panel to be held in the sash.

Glass panel with glazing gasket manufacturing method and manufacturing apparatus


A wave form for a water ride attraction having an inflatable cushion with a ride surface adapted to support a rider. The ride surface has a substantially planar section, followed by an upwardly inclined concave section, and then a horizontally inclined convex section. A wake form for a water ride attraction has an inflatable cushion having a ride surface. The ride surface has a substantially planar central section, flanked by an upwardly inclined concave section on one side and an upwardly inclined concave section on the other side. A water ride attraction has an inflatable wave form or wake form and a water delivery arrangement for delivering a flow of water to the inflatable wave form or wake form in a flow direction. The ride surface is arranged to allow a rider to ride on the flow of water in a direction generally transverse to the direction of water flow.

Amusement park attractions include wave machines that replicate natural waves. Wave machines typically have hard surfaces forming the ride sections of the wave machine. The hard surfaces do not absorb impact if a rider falls during or after riding a wave. It is known for riders to suffer broken bones, bruises, grazes and concussions as a result of falling while riding a wave on a water ride attraction.
Another disadvantage of known wave machines is the wave machine can only create one type of wave. Know wave machines do not create surfing waves and wake-type waves. Rather, two different wave machines are required for different wave types.
It is an object of the present invention to provide a water ride attraction that overcomes the disadvantages of known water ride attractions, and/or to at least provide the public with a useful alternative.


The present invention relates to the field of medicine and in particular to prophylaxis and therapy of diseases of pelvic and coxofemoral organs of a human body.

The present invention relates to the field of medicine and in particular to prophylaxis and therapy of diseases of pelvic and coxofemoral organs of a human body.
The prior art discloses devices for training muscles of locomotor system of a human body, rehabilitation after various diseases, prophylaxis of diseases. The devices comprise a supporting frame with a seat and dynamic elements for physical work of muscles. For better effect the devices are provided with an impedance generator allowing to control the individual physical work of each patient.
The trainer may have various building composition, different types of impedance generators and methods of their control /1, 2, 3, 4, 5, 6/.
Prior art teaches on use of a therapeutic effect of magnetic field for prophylaxis and treatment of various organs of a human body. The prior devices for magnetotherapy produce favorable effect both on the whole human body and on its selected organs /7, 8, 9/. In particular, devices for pulse magnetotherapy of gynecological diseases, prostatitis, etc., use pulse magnetic fields located in the immediate vicinity to treated organs /10, 11/. The devices are generally used at clinics and require constant control of medical personnel.
The claimed invention provides a device for dynamic physical work of the locomotor system of a human body. The seat of the device is mechanically connected to the dynamic elements for fisical work of musculs. The seat further comprises elements for carring out magnetotherapy of lumbar, coxofemoral and pelvic organs of a human body. The elements comprise a magnetic inductor, integral within the seat, and an impulse generator connected with the magnetic inductor through a modulating device.
The device additionally comprises a motion detector of the dynamic element. Physical work of a patient combined with the magnetic field effecting the body organs improves circulation of the blood, metabolism, hormonal processes, rehabilitation activity of physiological functions. A seats position of a patient rotating (pressing) the dynamic elements produces alternating compression and displacement of lumbar and coxofemoral organs of a human body making thereby massage of the organs. At the moment the motion detector generates a signal and supplies it to the modulating device. Accordingly, the effect of the magnetic field is synchronised with the location of an organ which is more favourable for creating an effect. Certain position of the locomotor system at maximum extension of muscular tissue provide the best approach of internal organs and the inductor, in particular of the postate and the inductor.
The device is additionally equipped with a audiosystem for listening-in music. Synchronously with the physical work on the trainer a patient is listening to harmonious musical sounds of the frequency that stimulates natural functions of a certain human organ. In parallel to that a signal from the audiosystem is supplied to the modulating device. Thereby the magnetic field is synchronized with the musical sound vibration effecting the human organ during listening-in.
The use of the aforementioned elements eliminates the necessity to introduce the inductor into the body and affords to use the magnetotherpy method and device outside a clinic.

Device for prophylaxis and treatment of diseases of lumbar, coxofemoral and pelvic organs of a human body

Abstract: The prophylactic and therapeutic effect is produced by combination of a physical work of human locomotor system subjecting of internal organs to modulated magnetic field. Magnetic field is modulated by signals supplied from the detector of motion or/and from the output of the audiosystem for listening-in music.


On receiving a symbol sequence carried by a first-polarization and a second-polarization signal of two orthogonally polarized signals and in order to cancel a cross polarization interference (XPI) component which leaks from the second-polarization signal into the first-polarization signal, a first decision feedback XPI canceller (43) is supplied with a before processed signal derived from the second-polarization signal and with a decided signal which is produced by a decision circuit (22) and which represents the symbol sequence carried by the second-polarization signal with an intersymbol interference component and another XPI component cancelled from the before processed signal. Another decision feedback XPI canceller (44) is similarly operable. Preferably, a first decision feedback equalizer (41) is supplied with another before processed signal derived from the first-polarization signal and with another decided signal which is produced by another decision circuit (21) and which represents the symbol sequence carried by the first-polarized signal with another intersymbol interference component and the first-mentioned XPI component cancelled from the last-mentioned before processed signal. A second decision feedback equalizer (42) is similarly used. Alternatively, a delay element is used instead of each decision feedback equalizer if the intersymbol interference components are negligible.

This invention relates to a cross polarization interference compensating or cancelling device for use in an orthogonal polarization communication system in which use is made of two orthogonally polarized signals of a common frequency.
Attention is recently directed in microwave radio communication to an orthogonal polarization communication system in which effective use is made of a first-polarization and a second-polarization signal as two orthogonally polarized signals of a common frequency. Into the two orthogonally polarized signals, differently polarized components are inevitably introduced due to heterogeneity which is given to a transmission medium by rain and the like. In other words, each of the two polarization signals are subjected to a cross polarization interference. Consequently, various cross polarization compensating devices are proposed for use in compensating for the interference.
One of such cross polarization compensating devices is described in a paper contributed by Hiroyuki Ohtsuka and two others under the title of "The SBS Control Algorithm of Cross Polarization Interference Canceller on Digital Radio Systems.revreaction. to the Transactions of the IEICE, Volume E 73, No. 3 (March 1990), pages 401 to 408. In the manner which will later be described more in detail, the cross polarization interference compensating device of Ohtsuka et al comprises a first equalizer for equalizing a first-polarization signal into a first equalized signal devoid of a first intersymbol interference component which is superposed on the first-polarization signal. A second equalizer equalizes a second-polarization signal into a second equalizer output signal exempted from a second intersymbol interference component superposed on the second-polarization signal. Supplied with the second-polarization signal, a first cross polarization interference canceller produces a first canceller output signal related to a first cross polarization interference component which is superposed on the first-polarization signal by the second-polarization signal. Supplied with the first-polarization signal, a second cross polarization interference canceller produces a second canceller output signal concerned with a second cross polarization interference component which is superposed on the second-polarization signal from the first-polarization signal.
A first adder adds the first canceller output signal to the first equalizer output signal to produce a first sum signal in which the first-polarization signal is exempted from the first intersymbol and cross polarization interference components. Similarly, a second adder produces a second sum signal. Supplied with the first sum signal, a first decision circuit produces a first decided signal representative of a symbol sequence carried by the first-polarization signal. Likewise, a second decision circuit produces a second decided signal representative of the symbol sequence carried by the second-polarization signal.
The conventional cross polarization interference compensating device is, however, defective in that the intersymbol and the cross polarization interference components are not reliably removed from the first and the second sum signals when become large. The decision circuits may misjudge the symbol sequence under the circumstances.

Cross polarization interference compensating device comprising decision feedback cross polarization interference cancellers


A lossless data compression system and method compresses a set of M data words stored in a computer memory. A first table stores data representing last occurrence positions among those of the M data words already processed for all distinct word values. A second table stores for each data word an entry indicating the position, if any, of a most recent prior occurrence of another data word with the same word value. A dictionary index indicates how many distinct data word values have been encountered during processing of M data words. The M data words are processed in in said M data words previously processed, identifying a longest sequence of data words starting with said each data word referencing said second table to identify data words earlier in said M data words than said each data word that match said each data word's value, identifying a longest sequence of data words earlier in said M data words than said data word which match an equal number of data words starting with said each data word, (B1) when said longest sequence's length is greater than one data word, outputting a run length code that indicates said longest sequence's length and position, and updating said first and second tables for the equal number of data words starting said each data word, and (B2) when said longest sequence's length is equal to one data word, outputting a code that indicates the position of said identified longest sequence, and updating said first and second tables for said each data word.

In most computers having virtual memory management, the available address space for the computer's operating system and application processes exceeds the amount of physical RAM available. As shown in FIG. 1, a computer system 100 will typically have a central processing unit (CPU) 102, such as a Motorola 68040 or Intel 80486, a primary memory 104 (typically random access memory (RAM)), a secondary memory 106 (typically one more magnetic or optical disks), and a cache memory 108 for storing a copy of the memory locations most recently addressed by the CPU 102. The cache memory 108, or a portion of the cache memory, is often fabricated as part of the same integrated circuit as the CPU 102.
As indicated in FIG. 1, the CPU 102 is typically the fastest of the components in the computer system, followed by the cache memory 108, the primary memory 104 and finally the secondary memory 106. Also shown in FIG. 1 is a virtual memory unit (VMU) 110, which is often fabricated as part of the same integrated circuit as the CPU 102.

Lossless data compression system and method


An OLED display is disclosed which included gate wires provided on a substrate and extended in a first direction, data wires provided on the gate wires and extended in a second direction that crosses the first direction; a pixel circuit including first thin film transistors respectively connected to the gate wires and the data wires; and an organic light emitting diode connected to the pixel circuit. The thin film transistor includes a first active layer provided on the substrate to connect the data wires and the organic light emitting diode, and includes a channel area, a source area, and a drain area. The source area and the drain area doped with an impurity and a first gate electrode is not doped with the impurity and provided on the first active layer, interposing sequentially layered first and second insulation layers therebetween.

1. Field
The described technology relates generally to an organic light emitting diode (OLED) display and a manufacturing method thereof. More particularly, the described technology relates generally to an OLED display including a pixel circuit including a plurality of thin film transistors and one or more capacitors, and a manufacturing method thereof.
2. Description of the Related Technology
Unlike a liquid crystal display (LCD), the OLED display has a self-light emitting characteristic so that a separate light source is not required. Therefore, the dimensions and weight thereof may be reduced. Further, because the OLED display has high quality characteristics such as low power consumption, high luminance, and high reaction speed, the OLED display is appropriate for use in a mobile electronic device.
In general, the OLED display includes gate wires provided on a substrate and extended in one direction, data wires extended in a direction crossing the gate wires, a pixel circuit connected with the gate wires and the data wires and including a switching thin film transistor, a driving thin film transistor, a driving thin film transistor, and one or more capacitors, and an organic light emitting diode connected with the pixel circuit.
Recently, a thicker insulation layer is formed between an active layer and a gate electrode of the driving thin film transistor compared to the switching thin film transistor in order to increase the driving range of a gate voltage applied to the gate electrode of the driving thin film transistor.
However, when an impurity is doped to a source area and a drain area of the active layer of each of the driving thin film transistor and the switching thin film transistor using the gate electrode as a mask, the impurity may not be easily doped to the active layer of the driving thin film transistor because the thicker insulation layer compared to the switching thin film transistor is formed between the active layer and the gate electrode of the driving thin film transistor.
Accordingly, the thickness of the insulation layer formed between the active layer and the gate electrode of the driving thin film transistor cannot exceed a predetermined thickness for impurity doping with respect to the active layer of the driving thin film transistor.

Organic light emitting diode display and method for manufacturing an organic light emitting diode display