A switching device include a buffer for temporarily storing a signal sent by a corresponding input terminal; variable channel transmission units, one of which is provided for each input terminal, for outputting a received signal with one of N different channels; fixed channel reception units, one of which is provided for each output terminal, for receiving the signal carried with a given channel and for outputting a signal with the given channel to a corresponding output terminal, with the given channel not overlapping any other; a variable channel control unit for synchronously altering, in consonance with predetermined patterns, channels with which the variable channel transmission unit outputs a signal, so that two or more variable channel transmission units do not simultaneously output signals with the same channel; and a buffer control unit for synchronously reading from the buffer a signal that is to be output, while altering the channel with which the variable channel transmission unit transmits a signal. Provided for the buffer is a function for sorting signals for output terminals at which the signals are to be output, and weighting of predetermined patterns is performed with a time at which one variable channel transmission unit outputs signals with the individual channels during one pattern cycle.

1. Field of the Invention
The present invention relates to a switching device that switches signals, especially signals that are assembled to form packets, and a network employing such a switching device; and to a simplified switching control method, and to a communication method employing such a switching method.
2. Related Background Art
Various types of conventional switching devices and methods have been studied and discussed. The structure of a packet that is switched by one of these packet switching devices is shown in FIG. 1. In FIG. 1, an address portion 109 holds output terminal instructions that specify the output terminal for the packet, while held in data portion 110 are the data that are carried in the packet.
FIG. 2 is a diagram of a first conventional example, a crossbar switching device that has N input terminals and N output terminals. In FIG. 2 decoders 111, each of which reads the address portion of a packet, transmit to a control unit 115 output terminal signals instructing the terminal equipments at which packets are to be output. Each FIFO (First In First Out) queue (hereinafter referred to as an "FIFO") 112 temporarily stores received packets, and, under the control of the control unit 115, outputs the packets across its output line 116 in the order in which they were received. Input lines 113 are employed to carry to the input terminals of switches 114 packet signals that are output at the FIFO 112. The switches 114 are used to select whether or not packet signals that are received along the input lines 113 are to be output to the output lines 116. In consonance with the output from the decoders 111 the control unit 115 receives, it determines when to read data from the FIFO 112 and when to open and when to close the switches 114. The output lines 116 are employed, along which packet signals that are output from the switches 114 are supplied to the output terminals.
In the crossbar switching device, the control unit 115 opens or closes the switches that are connected to required output terminals, and thus provides routing control for the changing of the output terminals to which signals are forwarded. Also, when a routing disagreement arises, as when there are requests for the output at the same output terminal of input data that have been received at multiple input terminals, i.e., when a so-called output conflict occurs, the control unit 115 performs arbitration control to determine, from among the input at the plurality of input terminals, the data that are to be output. The performance of these control processes constitutes the switching operation.
However, in the first conventional example, which has N input terminals and N output terminals, N.times.N switches are required. As a result, the size of the hardware is greatly increased.
In addition, in the first prior art, N output terminals of the switches, by which a plurality of input lines and output lines are connected together, are connected to a single output line. As a result, length of connecting lines is extended and this causes the wiring delays and an increase in the floating capacity of wiring. As the number N of the input terminals becomes greater, it is difficult to increase the operating speed of the switches. Thus, the first prior art can not adequately handle the high speed switching that is required for input packet signals.
Further, in the first prior art, the occurrence of output conflicts must be detected for all inputs at all the input terminals, and arbitration control must be performed. Therefore, because of the performance of this control, the size of the hardware for the control unit is increased.
FIG. 3 is a second conventional example that has been proposed to overcome the shortcomings of the first conventional example. For the design of a switching device, a plurality of 2.times.2 switches, each of which has two input and two output terminals, are connected together at multiple steps. In FIG. 3, 2.times.2 switches 117 through 128, each of which has two input terminals and two output terminals, perform two functions: a "straight" function for directly connecting input terminals to output terminals, and a "crossing" function in which switching paths intersect before they connect input terminals to output terminals. These twelve 2.times.2 switches are connected to form a shuffle network and thus provide an omega switching device that has eight input terminals and eight output terminals.
FIG. 4 is a diagram showing the internal structure of one of the 2.times.2 switches 117 through 128 that have two input terminals and two output terminals. In FIG. 4, a decoder I 129 and a decoder II 130 read the address portion of a received packet and notify a control unit 135 through which output terminal the packet is to be sent. An FIFO I 131 and an FIFO II 132 temporarily store received packets, and under the control of the control unit 135, they output the packets to respective selectors I and II, 133 and 134, in the same order in which the packets were input. The selectors I and II, 133 and 134, select the FIFO I 131 or II 132 in which is stored a packet signal that is to be output to an external destination. When the above mentioned straight function is performed, the selector I 133 selects the FIFO I 131, and the selector II 134 selects the FIFO II 132. When the crossing function is performed, the selector I 133 selects the FIFO II 132 and the selector II 134 selects the FIFO I 131.
In the second prior art, the number of required 2.times.2 switches is N log N-N/2 (2 is the log). Although this number is smaller than the N.times.N in the first prior art, each of the 2.times.2 switches requires decoders, FIFOs, a control unit and selectors, and thus the size of its hardware is large. In addition, in the second prior art, even if different input terminals are not connected to the same output terminal, an input terminal may not be connected to a desired output destination when a specific connection condition exists at of the other input terminals, i.e., a so-called blocking phenomenon will occur. For example, when input terminal 5 in FIG. 3 is connected to an output terminal 3, the 2.times.2 switch 117 is placed in the crossing state. However, in order to connect input terminal 1 to output terminal 1, the 2.times.2 switch 117 must be placed in the straight state. As a result, the blocking phenomenon occurs.
In a switching device, shown in the first and the second prior art, that employs electric switches, electric devices that can be switched at high speed are required for high speed processing. These electric devices are very expensive, and as a result the cost of manufacturing a switching device is increased. As one way to provide a high speed packet signal switching device, a switching device has been discussed that converts a packet signal into an optical signal and then switches the converted signal.
A third conventional example is of this type. In it, optical fibers are used to connect together, at multiple steps, a plurality of 2.times.2 optical waveguide switches, which have the same function as those in the second prior art, to provide an 8.times.8 switching device. In FIG. 5 are a schematic diagram and a cross sectional view of a total reflection InP optical switch, which is employed in the third prior art and which is one of crossing optical switches that are employed as 2.times.2 optical waveguide switches. In the total reflection InP optical switch, a carrier is introduced in a crossing portion where two optical waveguides cross each other to vary the refractive index in a refractive index variable region. Thus, an optical signal that enters the crossing portion is either transmitted or is totally reflected, and the switching is thereby performed. The variance of the refractive index that is induced by introducing a carrier is derived from band filling effects, during the shifting of the bands, according to which a change in a refractive index is increased as the wavelength of an incident light approaches the wavelength of an absorption end.
The introduction of a current into a refractive index variable region is performed with a carrier closing effect by using a p-InP clad layer and an n-InP substrate that have a large band gap, and by the constriction of a current in a Zn diffusion region. An InGaAsP cap layer is provided to obtain a preferable ohmic contact with an electrode. An optical switch must reduce the transfer loss for an optical signal and increase an optical quenching ratio (reduce cross talk). The refractive index must vary greatly in order to increase the optical quenching ratio. However, the above described optical switch is provided by using the band filling effect, and as the wavelength of incident light nears the wavelength at the absorption end, the transfer loss and the variance in the refractive index are increased. Setting the wavelength of incident light is difficult because, depending on the setting for the wavelength, a choice must be made as to whether a change in the refractive index should be reduced to prevent transfer loss and an increase in cross talk should be ignored; or whether a change in the refractive index should be increased to reduce cross talk and an increase in the transfer loss should be disregarded. Especially when 2.times.2 switches are to be connected, multiple steps for connection can not be employed due to a problem that arises from a trade-off involving transfer loss and a cross talk, and a large switching device can not be provided. In addition, since the response speed for the changing of the switches is limited by the lifetime of an injected carrier, high speed switching can not be performed.
In consideration with the above problems, the present inventor proposed the following switching device and switching method.
FIG. 6 is a diagram illustrating the structure of that switching device. The switching device has eight input terminals and eight output terminals and is constituted by eight variable wavelength transmission units I through VIII, which employ a tunable laser diode (TLD), and eight reception units I through VIII, which employ a photodiode (PD). In FIG. 6, each of the decoders I 136 through VIII 143 reads the address portion of an input packet, and transmits a destination instruction to a control unit 177 for the output terminal at which the packet is to be output. First In First Out queues (hereafter referred to as "FIFOs") I through VIII 144 through 151 temporarily store the packets they receive and then, under the control of the control unit 177, transfer the packets to the respective variable wavelength transmission units in the order in which they were received. Variable wavelength transmission units I 152 through VIII 159 are controlled by a wavelength control unit 179 in the control unit 177. They convert the packet signals that they receive from the FIFO I 144 through FIFO VIII 151 into optical signals having specific wavelengths and emit these signals to a star coupler 160. The star coupler 160 merges all the light of the wavelengths that are emitted from these eight variable wavelength transmission units 152 through 159 and then emits the light to eight filters 161 through 168. The filters I 161 through VIII 168, each functions to transmit only an optical signal having a fixed wavelength and to filter out optical signals having the other wavelengths. The transmitted wavelength .lambda.1 is set for the filter I 161; .lambda.2, for the filter II 162; .lambda.3, for the filter III 163; .lambda.4, for the filter IV 164; .lambda.5, for the filter V 165; .lambda.6, for the filter VI 166; .lambda.7, for the filter VII 167; and .lambda.8, for the filter VIII 168. The reception units I 169 through VIII 176 employ a photodiode to convert into electrical signals the optical signals that have the given wavelengths that are transmitted through the respective filters I 161 through VIII 168, and output each of the electric signals to a specific output terminal I to VIII. The control unit 177, which initiates the switching operation by the switching device, is constituted by an arbitration control unit 178 and the wavelength control unit 179. In consonance with instructions that are output by the decoders 136 through 143, the arbitration control unit 178 resolves output conflicts, between packets that have been input at the input terminals I through VIII, for each of the output terminals I through VIII at which the packets are to be output. The arbitration control unit 178 then issues an instruction to the wavelength control unit 179 that is consonant with the arbitration result. Upon the receipt of the instruction from the arbitration control unit 178, the wavelength control unit 178 controls the transmission wavelengths of the variable wavelength transmission units 152 through 159.
With the above described arrangement, since the eight filters I 161 through VIII 168 are so set that the wavelengths of optical signals that are transmitted through them are different, the wavelengths of the optical signals that enter the individual reception units differ and are independent. Therefore, a routing function for changing the output terminal for signal output can be provided by varying the transmission wavelength of the variable wavelength transmission units 152 through 159.
However, with this arrangement, arbitration control is required for packets that are input at all the input terminals.
Further, the transmission wavelength must be adjusted to a given wavelength for each packet in consonance with an instruction from the arbitration control unit. Therefore, when, for example, a packet has been forwarded with the shortest wavelength, and when a succeeding packet that is to be output has the longest wavelength, the magnitude of the change in the transmission wavelength that is performed by the variable wavelength transmission unit is great.
In this case, high speed wavelength control is required, so that the size of the hardware is increased or the time required for the processing to change the wavelength is extended.
As a similarly structured switching device, a technique called BHYPASS is disclosed in "Matthew S. Goodman; October 1989, IEEE Communication Magazine, pp. 27-35". While its arrangement is similar to that in FIG. 6, the device employs the Batcher-Banyan algorithm to control in advance the routing of packets, so that packets which are to be sent to the same output terminal are not input to a plurality of variable wavelength transmission units at the same time. The device also controls the wavelengths of the variable wavelength transmission units. With this arrangement, the advance control is required to ensure that packets which are to be sent to the same output terminal are not input simultaneously to a plurality of wavelength transmission units. In addition, the wavelengths of the wavelength transmission units must be adjusted in consonance with the packet destinations.

Simplified switching control device, and a network system for employing the device: and a simplified switching control method, and a communication method for employing the method


This invention relates to a semiconductor having protruding contacts comprising, a first semiconductor substrate having at least one interconnect located substantially within the first substrate, and a second semiconductor substrate having at least one protruding contact point that substantially contacts at least one interconnect.

1. Field of the Invention
This invention relates to a semiconductor having protruding contacts comprising, a first semiconductor substrate having at least one interconnect located substantially within the first substrate, and a second semiconductor substrate having at least one protruding contact point that substantially contacts at least one interconnect.
2. Description of the Related Art
Prior to the present invention, as set forth in general terms above and more specifically below, it is known in the semiconductor art, that two semiconductor substrates can be joined together at low temperatures by using well-known plasma-enhanced bonding processes. These low-temperature substrate joining techniques can be used to package MEMS (microelectromechanical systems) or NEMS (nanoelectromachanical systems) devices hermetically as well as 3-D wafer stacking. With respect to these low-temperature substrate joining techniques, the surface of the substrates to be joined need to be flat and very smooth (<20 A rms surface roughness over 2 μm×2 μm). Consequently, the surfaces are usually planarized with chemical mechanical polishing (CMP).
It is well known that the CMP planarization process creates some unique challenges for wafer-to-wafer interconnect applications since it is difficult to planarize the interconnect plug (or contact points) and the surrounding area evenly. The interconnect between two substrates may fail if dishing on the plugs occurs during the CMP process. Also, plasma-enhanced bonding may fail if the plugs surfaces are higher than the surrounding area, which prevents the two substrates from contacting at the atomic level.
It is also known, in the semiconductor art, that compliant intermediate layers (such as BCB (benzocyclobutene)) are often used to adhere two substrates together as well as to form an interconnect at the same time. This approach works fine for many 3-D interconnect applications, but does not work when both 3-D interconnect and hermetic packaging are required since BCB is not hermetic.
It is further known, in the semiconductor art, that Au bump or solder ball techniques can be used to flip-chip bond one substrate to another. However, none of these techniques provide both a good electrical interconnect between the substrates and hermetic packaging at the wafer level as the bumps or balls tend to cause a standoff between the circuits or substrates. The interconnect density is also limited with this approach.
Finally, it is known, in the interconnect art, to bond the interconnect to the pad of the circuit device. Typical techniques involve heat, eutectic bonding, electrical bonding, and/or mechanical bonding. However, many of these techniques do not provide an adequate bond for a variety of reasons.
It is apparent from the above that there exists a need in the semiconductor art for a semiconductor construction technique that works with both 3-D interconnect and hermetic packaging, but which at the same time allows the two substrates to be efficiently bonded so that they contact each other at the atomic level. It is a purpose of this invention to fulfill this and other needs in the art in a manner more apparent to the skilled artisan once given the following disclosure.

3D interconnect with protruding contacts

Hewlett-Packard Development Company, L.P.


In accordance with the present invention, there is provided a transition metal olefin polymerization catalyst component characterized by the formula:

Polymers of ethylenically unsaturated monomers such as polyethylene or polypropylene homopolymers and ethylene-propylene copolymers may be produced under various polymerization conditions and employing various polymerization catalysts. Such polymerization catalysts include Ziegler-Natta catalysts and non-Ziegler-Natta catalysts, such as metallocenes and other transition metal catalysts which are typically employed in conjunction with one or more co-catalysts. The polymerization catalysts may be supported or unsupported.
Homopolymers or copolymers of alpha olefins may be produced under various conditions in polymerization reactors which may be batch type reactors or continuous reactors. Continuous polymerization reactors typically take the form of loop-type reactors in which the monomer stream is continuously introduced and a polymer product is continuously withdrawn. For example, the production of polymers such as polyethylene, polypropylene or ethylene-propylene copolymers involve the introduction of the monomer stream into the continuous loop-type reactor along with an appropriate catalyst system to produce the desired homopolymer or copolymer. The resulting polymer is withdrawn from the loop-type reactor in the form of a "fluff" which is then processed to produce the polymer as a raw material in particulate form as pellets or granules. It is often the practice in the production of ethylene homopolymers and ethylene C3+ alpha olefin copolymers to employ substantial amounts of molecular weight regulators such as hydrogen to arrive at polymers or copolymers of the desired molecular weight. Typically in the polymerization of ethylene, hydrogen malt be employed as a regulator with the hydrogen being introduced into the monomer feed stream in amounts of about 10 mole % and higher of the ethylene feed stream.

Tridentate metal catalyst for olefin polymerization

Abstract: where, M is a Group IV or a Group IV transition metal, B is a bridge group containing at least two carbon atoms, A′ and A″ are organogroups, each containing a heteroatom selected from the group consisting of oxygen, sulfur, nitrogen and phosphorus, X is selected from the group consisting of chlorine, bromine, iodine, a C1-C20 alkyl group, a C6-C30 aromatic group and mixtures thereof, and n is 1, 2 or 3. The invention also encompasses a method for the polymerization of an ethylenically unsaturated monomer which comprises contacting a transition metal catalyst component as characterized by formula (1) above and an activating co-catalyst component in a polymerization reaction zone with an ethylenically unsaturated monomer under polymerization conditions to produce a polymer product.


Certain embodiments provide a face-down therapeutic system for improved posture and spine alignment. The system includes a face-piece including at least one cushion operable to receive a face of a user. The face-piece is adapted to be positioned on a flat surface. The system also includes two padded shoulder pieces, where each of the shoulder pieces is operable to receive a shoulder of the user. The shoulder pieces are adapted to be positioned on the flat surface. The system includes a padded pelvic-piece operable to receive a pelvis of the user. The pelvic-piece is adapted to be positioned on the flat surface.

As people age, the soft tissue attachments to the skeletal structure of the human body become less elastic, especially in areas with old injuries where scar tissue has developed. Traumas like car accidents and bad posture can result in forward head posture, reduced cervical curve (whiplash), thoracic hyper-kyphosis (Dowager's hump), lumbosacral hypokyphosis (military back) and hyperlordosis (sway back).
Inversion tables do traction the spine and discs but hanging upside down is uncomfortable to many people and can cause head pressure and ankle discomfort. The mechanical devices that are intended to traction are not as effective, take time out of the schedule to do, and can have mechanical issues.
Current spinal orthotics are usually placed under the supine person putting body weight on the padded, formed, rigid device, intending to improve the spinal curves. The pressure on the muscles and blood vessels impedes the circulation and prevents the muscles from being able to thoroughly relax, minimizing the stretch and reforming effects.
Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.

Face-down therapeutic system for improved posture and spine alignment


This invention relates to a process for preparing a flame retardant product predominant in tetrabromobisphenol-A. The process comprises: (a) dissolving bisphenol-A in a methanol solvent containing up to about 5 weight percent water, wherein the ratio of methanol to bisphenol-A ranges from about 25 to about 43 moles of methanol per mole of bisphenol-A based on the total amount of methanol used and the total amount of bisphenol-A to be brominated; (b) adding to the solution in (a) from about 3.9 to about 4.2 moles of bromine per mole of bisphenol-A to be brominated while maintaining a reaction temperature in the range of from about 0.degree. to about 40.degree. C.; (c) after the bromination is substantially complete, adding water to precipitate the tetrabromobisphenol-A thus formed; and (d) purifying the precipitated tetrabromobisphenol-A so as to obtain a product predominant in tetrabromobisphenol-A containing less than about 20 ppm total ionic impurity.

This invention relates to a process for preparing tetrabromobis-phenol-A and to an improvement in a process for enhancing the purity of a flame retardant product predominant in a tetrabromobisphenol-A.
4,4'-isopropylidenebis(2,6-dibromophenol) is a well known commercial flame retardant and is usually referred to as tetrabromobisphenol-A (hereinafter "TBBPA"). Products comprised predominantly of TBBPA are useful as flame retardants in many macromolecular formulations. The literature is replete with processes for the manufacture of TBBPA, see, for example, U.S. Pat. No. 3,029,291; U.S. Pat. No. 3,182,088; U. S. Pat. No. 3,234,289; U.S. Pat. No. 3,363,007; 3,546,302; U.S. Pat. No. 3,868,423; U.S. Pat. No. 3,929,907; U.S. Pat. No. 4,013,728; U.S. Pat. No. 4,036,894; U.S. Pat. No. 4,112,242; U.S. Pat. No. 4,180,684; U.S. Pat. No. 4,431,847; U.S. Pat. No. 4,451,675; U.S. Pat. No. 4,701,568; U.S. Pat. No. 4,990,321; U.S. Pat. No. 5,008,469; U.S. Pat. No. 5,059,726; U.S. Pat. No. 5,068,463; Japanese Kokai 2 (1990) 196,747; EPO 380,363; British Patent 949,306. Processes which produce a TBBPA predominant product having a particularly low organic impurity content are described in U.S. Pat. No. 4,628,124; U.S. Pat. No. 4,783,556; U.S. Pat. No. 4,909,997; U.S. Pat. No. 5,017,728; U.S. Pat. No. 5,059,722, and U.S. Pat. No. 5,138,103 incorporated herein by reference as if fully set forth. Most if not all of the foregoing processes describe the recovery of TBBPA from the reaction mass by adding water to precipitate the product.
While the processes described in the foregoing patents yield products which are useful for most flame retardant applications, there exists a need for a TBBPA predominant product having both low organic impurity and low ionic impurity. These low impurity TBBPA predominant products have particular application as flame retardants in polymers and plastics for the electronics industry.
A particularly useful process for enhancing the quality of a product predominant in TBBPA is disclosed in Application Ser. No. 614,372, filed Nov. 15, 1990, now U.S. Pat. No. 5,107,035.
There is also a need, due to impending environmental restrictions on the production and use of methyl bromide, for a process which substantially reduces the amount of methyl bromide formed as a coproduct when using methanol as reaction solvent. Accordingly, one object of this invention is to provide a facile economic means for substantially reducing the amount of methyl bromide coproduct formed without the need for substantial capital investment.

Process for high purity tetrabromobisphenol-A


A solvent-free process for making a polyol fatty acid polyester composition useful for preparation of polyurethanes is described. These compositions are preferably made by reaction of a natural oil (from plant or animal) with a multi-functional hydroxyl compound derived from a natural source, such as sorbitol, in presence of an alkali metal salt or base such as potassium hydroxide as a catalyst which also acts to saponify the reaction mixture. The hydroxyl content of the prepared composition depends on the amount of the multi-functional hydroxyl compound used in the preparation. In another embodiment, the hydroxyl groups of these compositions are reacted with an isocyanate, such as the polymeric diphenylmethane diisocyanate (also known as 4,4′-diphenyl methane diisocyanate, or MDI) to form polyurethanes in a conventional manner.

(1) Field of the Invention
This invention relates to a process for preparation of compositions of polyol fatty acid polyesters from plant and animal oils, reacted with isocyanates in high yield. Compositions as prepared are particularly used to produce biobased polyurethanes.
(2) Description of Related Art
Most of todays commercially available polyols are produced from petroleum. However, the depletion of petroleum combined with its increasing price in our modern societies has encouraged researchers and governments to explore new ways to produce todays polymeric materials from renewable and cheap natural resources.
Polyurethane resins are widely used in various applications ranging from medical devices to automotive body panels. The success of polyurethane is due to its ability to be produced in various forms from flexible to rigid structures. Applications include areas such as insulation, packaging, adhesives, sealants and coatings. Moreover, polyurethanes are now finding a growing market in the sector of composites for automotive applications such as seat pans, sun shades, door panels, package trays and truck box panels.
Polyurethanes are made by reaction between isocyanate groups (NCO) with hydroxyl groups (OH) when multi-functional compounds are used. A crosslinking agent or a chain extender may be used. The extent of crosslinking is crucial since it will determine the final properties such as elongation, stiffness, strength and resistance to solvents.
Most of the polyols currently used (>90%) in production of polyurethanes are either polyether and/or polyester polyols derived from petroleum, a non-renewable resource which is depleting. The price of petroleum is unpredictable, and thus so are the prices of these polyols. Moreover, the production of these polyols poses an environmental problem.
Preparation of polyols useful for polyurethane production from cheap and renewable natural oils is highly desirable in order to alleviate the present environmental threat. Natural oils consist of triglycerides of saturated and unsaturated fatty acids. One natural oil, i.e. castor oil, is a triglyceride of recinoleic acid (a fatty acid that contains hydroxyl groups) and is used to produce polyurethanes. Despite good thermal and hydrolytic stability when compared to their counterparts produced from petroleum-based polyols, these castor oil-based polyurethanes have not found a wide application. The major drawback is the limited hydroxyl content (ca. 100–170 mgKOH/g) of the oil, thus restricting its use to production of flexible and semi-rigid polyurethanes. Morever, castor oil is produced in tropical regions, which increases its cost when compared to oils such as soybean and corn for example. Therefore, other ways to make inexpensive polyols with controllable hydroxyl number from natural oils are needed.
In the case of other natural oils, they must be chemically reacted and converted to multiple hydroxyl structures useful in making of polyurethane resins. From a chemical point of view, natural oils offer two reactive sites, the double bonds of unsaturated fatty acids, and the carboxyl ester group linking the fatty acid to the glycerol.
Polyols useful for preparation of polyurethanes have been synthesized from natural oils by chemical reaction at the unsaturated sites (see U.S. Pat. No. 4,508,853 to Kluth, et al., and U.S. Pat. No. 6,107,403 to Petrovic et al.). There are two ways to make natural oil-based polyols for polyurethane preparation: (i) Epoxidation of double bonds followed by hydroxylation and (ii) the hydroformylation of double bond and subsequent hydrogenation of the carboxyl group to yield hydroxyl moieties.
In the epoxidation/hydroxylation process, the double bond is converted into an epoxy group that is further opened in acidic solution. Usually, the conversion to the epoxy is performed by a peroxyacid or peroxide. Reaction is carried out in the presence of a common solvent for both the peroxyacid and the oil or in a bi-phasic medium and depending on the reagents used a lot of side products can be formed.
In the hydroformylation/hydrogenation process, the oil is hydroformylated in a reactor filled with a mixture of hydrogen (H2) and carbon monoxide (CO) in the presence of a suitable organometallic catalyst (cobalt and rhodium catalysts work best) to form the aldehyde, which is subsequently hydrogenated in presence of a cobalt or nickel catalyst to form the required polyol. The reaction is carried out in a reactor.
These ways of making polyol from natural oils are limited to oils containing double bonds whose conversions to hydroxyl groups are not always well controlled. Indeed, undesirable aldehyde and epoxy groups are sometimes found in the polyol. Moreover, polyols with a high hydroxyl content (>250 mg KOH/g) are difficult to obtain. Besides, the use of a large number of reactants like peroxyacid, peroxide, hydrogen and carbon monoxide gases not only make the synthesis and processing more complicated with several byproducts whose removal to make pure polyol makes the process more energy intensive but also increase the overall cost of the resulting polyol. In addition, risks are associated with the use of reactants such as hydrogen and carbon monoxide gases and also peroxyacids (like m-chloroperbenzoic acid) and peroxide.
Some progress has been realized in the making of polyols for polyurethane preparation from natural oils by reaction at their carboxyl ester groups. In a patent (WO 01/04225 A1), Shah et al mixed vegetable oils with polyhydroxy alcohols such as glycerol in the presence of carboxylic acids and a catalyst under nitrogen atmosphere. In another recent patent, Kurth et al (U.S. Publication No. 2002/0058744 A1) described the preparation of vegetable oil-based polyols in a two-stage process. In the first stage they prepared a reaction product mixture of multifunctional alcohol and saccharide that reacts in the second stage with a vegetable oil in presence of a transesterification catalyst. The disclosure of this application is incorporated by reference herein.
Other pertinent applications and publications are: U.S. Pat. No. 4,518,722 to Volpenheim, U.S. Pat. No. 5,006,648 to Pleun Van der Plant, et al., U.S. Pat. No. 5,596,085 to Silver et al., and U.S. Pat. No. 4,812,533 to Simone et al. These are also incorporated by reference.
Objects
In accordance with the current invention, it is an object to overcome the deficiencies found in the described processes for making natural oil-based polyols in a cost effective one-stage process and to use them for making biobased polyurethanes. A further object of this invention is the control over the hydroxyl content of polyols and thus the possible tuning of the mechanical properties of the subsequent polyurethanes through the control of crosslinking within the polymer network. A further object is to provide a process which is 'green' and eco-friendly. It is finally an object to provide biobased polyurethanes which can be used in various applications as matrix for biocomposites, resins, foams and coatings.

Polyol fatty acid polyesters process and polyurethanes therefrom

Board of Trustees of Michigan State University


A drive device for driving two members includes one drive source; a rotating member connected to the drive source; and a drive member connected to the rotating member via a coupling device. The drive member stops upon releasing the connection from the rotating member via the coupling device after moving for a predetermined distance in synchronicity with the rotating member. The rotating member and the drive member drive the two members, respectively.

The present invention relates to a drive device for driving two members in which a single drive source opens/closes or slides a shutter member for opening and closing an opening of a storage section in a vehicle, a cover for opening and closing a portion of the storage section, or a storage member for sliding back and forth within the storage section, so that, for example, an electronic system installed in the vehicle becomes invisible from outside through a window of the vehicle. The present invention also relates to a shielding system for a vehicle having the drive device for driving two members for opening/closing or sliding a shutter member, cover, or storage member.
In recent years, an electronic equipment such as navigation system and audio system installed in a parked vehicle has been often stolen. One of contributing factors may be that such a system installed in a vehicle is visible from outside through a window. In order to shield and make the system installed in a vehicle invisible, an installation rack has been proposed (Patent Reference 1). The installation rack includes a storage space for storing an article; a rack main body having a front opening, a shutter for opening and closing the storage space, a first drive mechanism for opening and closing the shutter, a slide member disposed in the rack main body to be slidable in a longitudinal direction; and a second drive mechanism for sliding the slide member.
Patent Reference 1: Japanese Utility Model Publication (Kokoku) No. 05-21498
The conventional installation rack described above is provided with motors each driving the first drive mechanism for opening and closing the shutter and the second drive mechanism for sliding the slide member. Accordingly, it is necessary to provide a space for installing the two motors, thereby making it difficult to use a space effectively and increasing cost of the installation rack due to the two motors.
In view of the problems described above, an object of the present invention is to provide a drive device for driving two members provided with a single drive source.
Further objects and advantages of the invention will be apparent from the following description of the invention.

Drive device for driving two members and shielding system for vehicle


A control system for an electrical motor drive for moving a door between end positions. The two end positions are detected by the control system, and an increment detector associated with the motor drive reproduces the movement cycle of the door. A stop associated with the motor drive marks an end position of the door that corresponds to the open position thereof. This open position is treated as a reference point. A pulse storage device is set to a specific value at this reference point and initiates the beginning of a pulse sequence to reproduce movement of the object between the end positions. The pulse sequence is compared for coincidence with pulses produced by the increment detector upon movement of the door into the opposite end position that corresponds to its closed position.

Drive systems for an object which is movable to and fro between to end positions are known and are preferably associated with electric motor drives. One example of an object movable in the above-described manner is a door leaf that can be moved between its open and closed positions.
From document EP 0 280 854 it is known to realize such a control system where the position detection in the end positions is not definite, but where a reference point within the door leaf travel is taken as a parameter to determine the actual door leaf position from comparing the reference point with a stored pulse number that reproducing the end positions of the object. This is aided by counting pulses from an increment detector associated with the door leaf drive motor. The positions are input in a memory on the installation of the door leaf. Because of the traversing of the reference point, continual checking takes place of the actual state of the door leaf movement, so that a correction is possible for the set value position in the course of each phase of the travel.
According to an embodiment of the above-mentioned patent, monitoring of the movement of a door leaf in both moving directions takes place on the basis of the location of the reference point between the end positions of the door leaf.

Control for the drive of an object movable to and fro between two end positions

Marantec Antriebs- und Steuerungstechnik GmbH & Co. Produktions KG


An apparatus and method for discovering and monitoring a collection of nodes in a downhole network may include receiving data packets originating from several downhole nodes. These packets may be read to extract a unique identifier and hop count for each of the nodes. This information may then be used to create entries in a network topology table corresponding to each of the downhole nodes. Each entry may contain unique identifier identifying the respective node, a hop count identifying a location of the node within the downhole network, and a direction identifier. The method may further include modifying one or more entries in the topology table having a conflicting hop count and direction identifier.

1. Field of the Invention
This invention relates to downhole drilling and more particularly to apparatus and methods for managing and discovering network topology in a downhole drilling environment.
2. Description of the Related Art
The ability to transmit data at high speeds along a drill string is a current goal and project of the downhole drilling industry. More and better information at the surface has the ability to significantly decrease drilling costs by enabling operators to more accurately direct the drill string to hydrocarbon deposits. Such information may also improve safety and reduce the environmental impacts of drilling. This technology may also be desirable to take advantage of numerous advances in the design of tools and techniques for oil and gas exploration, and may be used to provide real-time access to data such as temperature, pressure, inclination, salinity, and the like, while drilling.
In order to transmit data at high speeds along a drill string, various approaches have been suggested. Very few approaches, however, have achieved commercial implementation due to the high costs of development and constraints imposed by the downhole environment. One approach that is currently showing promise is to incorporate a "network" of data transmission cable and other communication equipment into the drill string. Due to the length of drill strings, which may exceed 20,000 feet, this may require placing network "nodes" at selected intervals along the drill string. These nodes may act as repeaters to amplify the data signal and to provide points of data collection along the drill string.
Nevertheless, implementing and maintaining a network in a downhole environment is a difficult task. Unlike many conventional networks, the topology of a downhole network may be in a constant state of flux. That is, the number and positioning of nodes, as well as the status of each of the nodes may change frequently in the network. For example, nodes may be added or removed from the network at the surface either one or several at a time. In other cases, breaks may occur in transmission lines or other transmission components that may cause particular nodes or groups of nodes to temporarily or permanently lose communication with the surface. In other cases, the nodes themselves may temporarily or permanently cease to function. These characteristics make it a challenge to discover, monitor, and manage network components in a downhole environment.
In view of the foregoing, what is needed is an apparatus and method for discovering, monitoring, and managing network components in a downhole environment. Ideally, such an apparatus and method would provide an up-to-date view of network topology, identify network components and their position within the network, and identify the operating status of the components. Further needed is an apparatus and method to detect changes to network topology frequently or in real time. Yet further needed is an apparatus and method to perform each of the above functions while minimizing traffic on the network.

This patent is subject to a terminal disclaimer.

Directional topology discovery for downhole networks


A quartz crystal resonator element includes a first electrode pad and a second electrode pad disposed on a lower surface of a support arm, and cut sections disposed in both principal surfaces (upper and lower surfaces) of the support arm between the first and second electrode pads so as to overlap each other, and the cut sections extend so that the support arm is cut from the side surface in the +X-axis direction of the support arm to the −X-axis direction, and are provided with first surfaces roughly perpendicular to the X axis and first and second tilted surfaces extending in the +X-axis direction.

1. Technical Field
The present invention relates to a resonator element, a resonator, an electronic device, an electronic apparatus, and a moving object.
2. Related Art
In small-sized information equipment such as a hard disk drive (HDD), a mobile computer, or an IC card, mobile communication equipment such as a cellular phone, a smartphone, or a tablet terminal, and so on, an electronic device such as a resonator or an oscillator is widely used as a device for providing a timing signal or a sync signal.
In the past, there has been known a device having a resonator element housed in a package as a resonator or an oscillator (see, e.g., JP-A-2006-345519 (Document 1)). The resonator element disclosed in Document 1 has a base section, two vibrating arms extending from the base section so as to be arranged in parallel to each other, and a support arm extending from the base section and located between the two vibrating arms in order to reduce the total length of the resonator element to achieve the miniaturization. Further, each of the vibrating arms has electrodes disposed respectively on four surfaces constituting the periphery of the vibrating arm, and each of the electrodes is connected to either one of two electrode pads disposed side by side on one of principal surfaces of the support arm and having respective polarities opposite to each other via a wiring pattern disposed on a side surface of the support arm. Such a resonator element is fixed to the package in the portions of the two electrode pads via an electrically-conductive adhesive, and is electrically connected to the electrodes on the package side.
Each of the electrodes, the wiring pattern, and the two electrode pads are formed using a photolithography technique and a wet-etching technique.
However, in some cases, the metal in an unwanted area among the metal deposited on the side surface of the support arm fails to be completely removed even using the photolithography technique and the wet-etching technique. In the resonator element disclosed in Document 1, there is caused a problem that the metal, in particular the metal in the area to be separated as opposite polarities in the wiring pattern, fails to be removed. In other words, since the side surface of the support arm is formed roughly perpendicularly to the principal surface roughly along the crystal Z axis of the quartz crystal, it is unachievable to successfully expose a resist film disposed on the surface of the metal thus deposited in the pattern formation of the side surface, and there is caused a problem that the metal in the area from which the metal should be removed fails to be removed as expected. As a result, since the metal which should be removed remains unremoved on the side surface of the support arm, there is a problem that it is unachievable to electrically separate the wiring pattern into the opposite polarities, and as a result the two electrode pads become short-circuited.
Therefore, in JP-A-2004-072609 (Document 2), there is described a technology of removing the metal in the area, which should electrically be separated, in the wiring pattern formed on the predetermined side surface of the resonator element by forming a cutout having a tilted surface.
If the technical concept described in Document 2 is applied to electrical separation of the wiring pattern formed on the side surface of the support arm, a shape shown in FIGS. 14A and 14B is expected. The support arm 23a of the second embodiment has a cut section 118a on the upper surface between first and second electrode pads 37, 38 disposed on the lower surface of the support arm 23a. The cut section 118a extends from a side surface 120a in the +X-axis direction of the support arm 23a toward the −X-axis direction, and is provided with a side surface 119c roughly perpendicular to the X axis, and a tilted surface 119a extending in the +X-axis direction as shown in FIG. 14B.
However, as shown in FIGS. 14A and 14B, since the depth of the tilted surface of the cut section becomes deep, it is necessary to increase the support arm in width direction as a result in order to ensure the strength, and there arises a problem that the miniaturization is difficult.

Quartz resonator with cut sections formed on the support arm


A sheet feed device of an image forming apparatus includes an outside cover and an inside cover. The outside cover opens and closes a side of a housing. The inside cover is disposed more inside of the housing than the outside cover. Each of the covers is rotatably supported with a lower end thereof as a fulcrum by the housing. A first locking piece is provided in the upper end of the outside cover, and a second locking piece is disposed below the first locking piece. A coupled portion configured to be selectively coupled with the first locking piece or the second locking piece is provided in the inside cover. During the process where the outside cover is rotationally moved in the opening direction, the coupled portion is once released from the coupling with the first locking piece, and then is coupled with the second locking piece.

The present disclosure relates to a sheet feed device in which an outside cover and an inside cover, which can open and close a housing, are disposed in alignment, and to an image forming apparatus.
A conventional image forming apparatus such as a coppier or a printer, includes a sheet conveying device for extracting a sheet member (print sheet) stored in a sheet feed cassette, and conveying it. The sheet feed device includes a rotating roller that contacts the sheet member. A rotational driving force of a direction is transmitted to the rotating roller from a motor or the like, thereby the sheet member is conveyed along a conveyance path formed inside the image forming apparatus. In this kind of image forming apparatus, a side cover is provided to expose the conveyance path. For example, a typical image forming apparatus includes a cover that is rotatably supported, with its lower end as a fulcrum. With such a side cover provided, when a jamming of a sheet member occurs in the conveyance path, the user can open the side cover to expose the conveyance path, and easily remove the sheet member from the conveyance path.
Meanwhile, in the case where a conveyance path is formed inside an image forming apparatus, if only one side cover is provided to expose the conveyance path, the side cover needs to have a large thickness. However, when the side cover has a larger thickness, the rotational radius around the fulcrum becomes larger, and the image forming apparatus needs to be larger in height. In view of this, to restrict the image forming apparatus from becoming large in height, a plurality of side covers can be aligned between a side surface of the image forming apparatus and the conveyance path.
In the above-mention configuration where a plurality of side covers are aligned, when an outside side cover positioned in the side surface of the image forming apparatus is rotationally moved, an inside side cover needs to be rotationally moved in conjunction with the rotational movement of the outside side cover. As a mechanism for causing the two side covers to be rotationally moved in conjunction with each other, a mechanism is known in which the outside side cover is coupled with the inside side cover by a link member such as a connecting rod.

Sheet feed device and image forming apparatus


A method of manufacturing an MOS transistor having a gate length dimension less than the dimension available by methods available with conventional manufacturing methods that are limited by optical diffraction in photolithography. The method includes forming a polysilicon gate structure on a gate oxide layer, forming a nitrogen-doped layer on the polysilicon gate structure, forming selected depth oxide sidewalls on the polysilicon gate structure and etching the nitrogen-doped layer and the oxide sidewalls.

1. Field of the Invention
This invention relates generally to the manufacture of MOS integrated circuit transistors and more specifically this invention relates to the manufacture of
MOS integrated circuit transistors having a dimension below the photolithography limitation.
2. Discussion of the Related Art
MOS transistors are used extensively in semiconductor integrated circuit devices. A typical MOS structure is shown in FIG. 1. The typical MOS structure 100 is formed on a semiconductor substrate 102. A source 106 region and a drain 108 region are formed in the semiconductor substrate 102. A gate oxide region 110 is formed on the semiconductor substrate 102. A polysilicon gate 112 is formed on the polysilicon gate 112 and oxide spacers 114 and 116 are formed on each side of the polysilicon gate 112. The gate length is represented by the distance 118 and is dependent upon the dimension 120 of the polysilicon gate 112. Because the strategic approach to improving the speed performance of MOS devices is to continuously reduce device dimensions, especially the gate lengths, it is necessary to decrease the polysilicon dimension 120. The evolution of MOS device technology has been governed mainly by device scaling and the feature size of the MOS gate length has been scaled down in the effort to increase the speed and scale of integration.
The problem with the further scaling of the MOS transistor gate length is the limitation of photolithography technology. The smallest feature size that photolithography technology can pattern is limited by optical diffraction. Current manufacturing lithography technology that uses UV or deep UV light as the light source is not able to pattern the polysilicon gate to achieve a gate length of 0.1 .mu.m and below.
One method that has been used to achieve dimensions below the limitations of the photolithography technology is a technique called over etching. However, it is very difficult to control the shape and the size of the structures when using the technique of over etching.
Therefore, what is needed is a method of manufacturing MOS transistors that achieves device dimensions below the limitations of photolithography.

Method of manufacturing a polysilicon gate having a dimension below the photolithography limitation


A method and system for analog beamforming for wireless communication is provided. Such analog beamforming involves performing channel sounding to obtain channel sounding information, determining statistical channel information based on the channel sounding information, and determining analog beamforming coefficients based on the statistical channel information, for analog beamforming communication over multiple antennas.

With the proliferation of high quality video, an increasing number of electronic devices (e.g., consumer electronics (CE) devices) utilize high-definition (HD) video. Conventionally, most systems compress HD content, which can be around 1 gigabits per second (Gbps) in bandwidth, to a fraction of its size to allow for transmission between devices. However, with each compression and subsequent decompression of the signal, some data can be lost and the picture quality can be degraded.
The existing High-Definition Multimedia Interface (HDMI) specification allows for transfer of uncompressed HD signals between devices via a cable. While consumer electronics makers are beginning to offer HDMI-compatible equipment, there is not yet a suitable wireless (e.g., radio frequency (RF)) technology that is capable of transmitting uncompressed HD signals. For example, conventional wireless local area networks (LAN) and similar technologies can suffer interference issues when wireless stations do not have sufficient bandwidth to carry uncompressed HD signals.
Antenna array beamforming has been used to increase bandwidth and signal quality (high directional antenna gain), and to extend communication range by steering the transmitted signal in a narrow direction. However, conventional digital antenna array beamforming is an expensive process, requiring multiple expensive radio frequency chains connected to multiple antennas.

Method and system for analog beamforming in wireless communications


An optically based feed structure is used to distribute appropriately phased signals from a central signal generator to the individual elements of a phased array antenna. Any phase can be generated by adding together four phased signals (phased by 90 degree increments) if the amplitudes of the individual phased signals are appropriately controlled. By appropriately controlling the amplitude of the individual phased signals the amplitude of the resultant can also be controlled. In many cases it is desired to keep this amplitude constant. In some cases an amplitude taper across the phased array is desired.

The present invention relates generally to microwave antennas, and more specifically the invention pertains to an optical feed structure for controlling microwave phased array antennas.
A phased array antenna is a network of radiating elements, having a cooperative radiation pattern that is a highly directive beam. Whereas conventional radar antennae have to be mechanically steered to meet beam directing requirements, a phased array achieves the same effect electronically by changing the phase of the signal radiated by each element. Thus, accurate beams are formed and directed simply by driving each element of the array with a signal having an appropriate phase. As a further advantage, electronic steering is much faster than mechanical steering.
The flexibility of electronic steering provided by phased arrays requires individual control of each element. In an array having N elements, each of the elements is driven with a different phase of the same signal.
Electronically scanned radars include a feed network which couples microwave energy from the transmitter to a radiating aperture of the antenna, as well as from the aperture to the receiver. Feed networks are constructed in a variety of forms, with the corporate feed being particularly useful in providing an accurate distribution of microwave energy across the radiating aperture.
The task of providing an optical system for controlling microwave phased array antennas is alleviated to some extent by the systems disclosed in the following U.S. patents, the disclosure of which are specifically incorporated herein by reference:
U.S. Pat. No. 4,956,603 issued to Hong et al; PA1 U.S. Pat. No. 4,814,773 issued to Wechsberg et al; PA1 U.S. Pat. No. 4,583,096 issued to Bellman, et al; and PA1 U.S. Pat. No. 3,878,520 issued to Wright et al.
The patents identified above relate to fiber optic network apparatus for phased array radar systems. In particular, the Hong et al. patent describes an optical beamforming network for controlling the RF radiation pattern of a phased array antenna. A spatial light modulator is user-programmed with a desired far field radiation footprint, and modulates the light from a laser. The modulated light beam is directed through a Fourier transform lens and onto a beam splitter. The light is then combined with light from a second laser that is frequency offset by the RF center frequency of the antenna. Light from the beam splitter is recovered by first and second fiber optic bundles, and each optical fiber leads to a corresponding photodetector. The outputs of corresponding photodetectors of the two fiber optic bundles are combined to control the radiation of a corresponding radiation element of the phased array.
The Wechsberg et al patent relates to an optical feed system capable of coupling an antenna with transmitting and receiving circuity. The feed system comprises a set of optical multiplexers interconnected by sets of optical fibers. The microwave energy of the radar is converted to optical radiation for communication to the antenna, where it is converted back to microwave energy. Electro-optic modulators and photoelectric detectors provide the energy conversion. A plurality of signals can be simultaneously coupled via the optical fibers by utilization of radiation of differing frequencies.
The Bellman et al patent describes a system for fiber optic distribution of data in which digitally encoded data drives an optical light source which illuminates a bundle of fibers. A fiber from this bundle is terminated in the vicinity of each element of one row of a phased array. A photosensor on a transmit/receive element receives the modulated light signal. A similar but independent light source and fiber optic bundle is provided for every row of the array. Similar sources and fiber optic bundles are independently provided for every individual column of the array.
The Wright et al patent relates to an optically operated microwave phased array antenna system. Two optical beams are generated with a difference frequency equal to the desired microwave frequency to be transmitted. The two beams are combined to produce a two dimensional optical pattern that contains the correct microwave phase and amplitude information to form and steer the final antenna beam in space. The optical pattern is actually an optical analog of the microwave excitation applied to the antenna radiating elements. A transducer system converts the optical pattern to a two dimensional microwave pattern which is a two dimensional array of microwave signals. Each signal is connected to a single radiating element of a phased array antenna. These elements cooperate to radiate a beam in space.
The references described above demonstrate an ongoing need for optical control systems for use with microwave phased array antennas. The present invention includes an optical feed structure that is designed to help satisfy that need for both radar and communication microwave antenna systems.
Microwave beamforming in phased array antennas requires that each element of the array transmit a properly phased microwave signal so that the desired far field beam pattern is created. Conventional electronic methods for phased array feed systems tend to be expensive, bulky, lossy, inefficient, and susceptible to electromagnetic interference. Several other optical implementations for microwave beamforming have been proposed. The present invention does not require numerous lossy optical switches as does the switched fiber approach, nor does it require a segmented mirror device.

Optical system for microwave beamforming using intensity summing

The United States of America as represented by the Secretary of the Air Force


The invention provides a polyglycolic acid sheet obtainable by melt-extruding a thermoplastic resin material into a sheet in a temperature range of from the melting point, Tm of the polymer to 255.degree. C., wherein the thermoplastic resin material comprises polyglycolic acid having a repeating unit represented by the following formula (1): ##STR1## and the following physical properties: (a) the melt viscosity, .eta.* as measured at a temperature of (the melting point, Tm of the polymer+20.degree. C.) and a shear rate of 100/sec! being 500-100,000 Pa.s;. (b) the melting point, Tm being at least 150.degree. C.; PA1 (c) the melt enthalpy, .DELTA.Hm being at least 20 J/g; and PA1 (d) the density being at least 1.50 g/cm.sup.3 as measured in an unoriented, crystallized form, and the sheet has tensile strength of at least 60 MPa, and a production process thereof.

In recent years, increase in plastic waste has become a great social problem. Since many of polymeric materials have hitherto been developed and produced in search of high performance and long-term stability, they are not easily decomposed in a natural environment. Therefore, how to dispose and manage a large quantity of plastic waste which has become useless becomes a social problem on a world-wide scale. The plastic waste includes sheets formed from a variety of synthetic resins, such as polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyethylene terephthalate, polyamide resins such as nylon, and chlorine-containing resins such as polyvinylidene chloride, and trays and containers obtained by secondarily processing these sheets.
Under the circumstances, biodegradable polymers, which are degraded by natural microorganisms, attract attention as polymeric materials which impose no burden on the environment. The biodegradability can be evaluated by, for example, a degradability test in soil (soil degradability test). Since plastic sheets are required to have good mechanical properties, thermal properties, barrier properties, melt processability, profitability and the like, however, any plastic sheet, which fully satisfies these requirements and exhibits biodegradability, has not been yet obtained.
Among the conventional biodegradable plastic sheets, for example, sheets based on starch are unsatisfactory in toughness, barrier properties and heat resistance and involve a problem that they are difficult to melt-process, so that its processing cost becomes high. Sheets based on cellulose are unsatisfactory in toughness and involve a problem that they are difficult to melt-process, so that its processing cost becomes high. Sheets based on a microorganism-produced polyester are unsatisfactory in toughness and involve a great problem that their production cost becomes particularly high. Sheets based on a synthetic type polyester such as a polysuccinate are unsatisfactory in toughness and barrier properties and involve a problem that succinic acid and butanediol, which are raw materials for the polyester, are considerably expensive.
Sheets based on polylactic acid, which is a semi-synthetic type polyester, are unsatisfactory in toughness. Since L-lactic acid, which is an optically active substance used as a raw material, is required to have a high purity, the sheets must be produced through fermentation of a biological process, and there is hence a limit to their production at low cost. Further, since polylactic acid has a high glass transition temperature, Tg, it also involves a problem that it is difficult to compost under ordinary composting conditions.
With respect to films based on polyglycolic acid, which are synthetic polyester films, Higgins et al. (U.S. Pat. No. 2,676,945, issued in 1954) disclose amorphous films having a thickness of 3 mils and biaxially stretched films obtained by stretching them. These films are those obtained by using a polymer obtainable by directly polycondensing glycolic acid, not a polymer obtainable by ring-opening polymerization of glycolide. However, the polycondensation process of glycolic acid includes heating and polycondensing glycolic acid for a long period of time as about 40 hours at a high temperature of at least 200.degree. C. and hence tends to involve side reactions such as decomposition reaction. Accordingly, this process is difficult to provide a practicable polymer having a high molecular weight. U.S. Pat. No. 2,676,945 describes, in its example, the melt viscosity of the polymer as about 2,000 poises (at 245.degree. C.). This melt viscosity value corresponds to a value measured at a shear rate of about 0/sec. This melt viscosity value corresponds to a value extremely as low as about 20 poises (at 245.degree. C.) when converted into a value measured at a shear rate of 100/sec. In addition, there is a high possibility that this polymer may have an unstable structure due to side reactions. Accordingly, an extrusion film formed from the polymer obtained by such a direct polycondensation process has extremely low mechanical strength as demonstrated by its tensile strength extremely as low as 5,470 psi (about 39 MPa) and hence has involved a problem that it is unsatisfactory from the view point of practical use.
Gilding et al. POLYMER, 20, 1459 (1979)! provide films having a thickness of 250 .mu.m from 20% solutions of glycolic acid copolymers (glycolide/lactide=90/10, 70/30, 50/50, etc.) by a casting process. However, this process tends to form coarse spherulites upon evaporation of a solvent, and the resultant films are hence extremely brittle and unsatisfactory in mechanical strength from the viewpoint of practical use.
Japanese Patent Application Laid-Open Nos. 256480/1994 and 256481/1994 disclose that polyglycolic acid having a viscosity-average molecular weight of 280,000 or 250,000 was used as a raw material, this polymer was melt-extruded and cast at 280.degree. C. into an unoriented sheet, and the unoriented sheet was then stretched 3 times in a machine direction and 4 or 3 times in a transverse direction at 160.degree. C. to obtain a biaxially oriented film (in each document, Example 3). However, polyglycolic acid tends to undergo thermal decomposition at a temperature exceeding about 255.degree. C. and actually substantially undergoes thermal decomposition at the temperature as high as 280.degree. C., so that any satisfactory unoriented sheet cannot be obtained. It is a matter of course that if such an unoriented sheet is biaxially stretched, it is scarcely possible to obtain a biaxially oriented film having sufficient strength. An amorphous sheet of polyglycolic acid is crystallized at a temperature exceeding its crystallization temperature Tc.sub.1 (about 80.degree. C.) and highly crystallized at a temperature as high as 160.degree. C., so that the biaxial stretching of the amorphous sheet, for example, 3 times in a machine direction and 3 or 4 times in a transverse direction, is extremely difficult or actually impossible under such stretching conditions. Accordingly, any sheet or oriented film having sufficient strength cannot be obtained under the conditions disclosed in these publications. Besides, the meaning of the viscosity-average molecular weight of 250,000 or 280,000 and its measuring method are also unclear. Accordingly, it can be hardly said that these publications actually disclose high-molecular weight polyglycolic acid in the light of the state of the art.

Polyglycolic acid sheet and production process thereof


The present invention provides a line over driving (LOD) table adjustment method and a system thereof, which divides a display panel into M*N blocks. In an i-th row and a j-th column in the LOD table corresponding to a block, according to a brightness value of a grayscale value of a pixel of a previous line and a current line corresponding to an initial grayscale value of over driving pixels, calculate a target brightness value of an adjustment screen corresponding to a combination of the grayscale value of the pixel of the previous line and the current line corresponding to the initial grayscale value of over driving pixels, and obtain a measured brightness value of the adjustment screen to compare whether the difference between the target brightness value and the measured brightness value is within the default error range value to determine a final grayscale value of over driving pixel.

Thin-film transistors (TFTs) are main driving elements in current liquid crystal display (LCD) devices and active-matrix organic light-emitting diode (AMOLED) display devices, and directly relate to display performance of flat panel display devices.
Most of the LCD devices in current market are backlight type LCD devices having an LCD panel and a backlight module. The working principle of the LCD panel is to apply a pixel voltage and a common voltage on a TFT array substrate and a color filter (CF) substrate, control rotation direction of liquid crystal molecules between these two substrates by an electric field formed by the pixel voltage and the common voltage, and let light of the backlight module transmit to produce images. A forming process of the LCD panel generally includes: an array process of front-end-of-line (such as thin-film, photolithography, etching, and stripping), a cell process of middle-of-line (such as laminating a TFT substrate to a CF substrate), and module assembly process of back-end-of-line (such as bonding a driving integrated circuit (IC) to a printed circuit board). The array process of front-end-of-line mainly forms the TFT substrate for controlling motion of the liquid crystal molecules. The cell process of middle-of-line mainly fills liquid crystal between the TFT substrate and the CF substrate. The module assembly process of back-end-of-line mainly integrates the driving IC and the printed circuit board for driving the liquid crystal molecules to rotate and displaying the images.
The LCD panel in the prior art usually adopts a pixel driving circuit having a flip-pixel structure. The pixel driving circuit includes a plurality of sub-pixels arranged in an array and a plurality of data lines extending in a vertical direction, and the plurality of sub-pixels in a column interleaved connect to its left and right neighboring the plurality of data lines.
Due to a characteristic of a longer response time of the liquid crystal and a shorter charging time of high resolution and high refresh frequency LCD panels, a charging of a solid color image (e.g. a grayscale value of all red sub-pixels and blue sub-pixels is 0, and a grayscale value of all green sub-pixels is 210) and a charging of a pure grayscale image (e.g. a grayscale value of all red sub-pixels, blue sub-pixels, and green sub-pixels is 210) have a significant difference. The charging of a solid color image often cannot achieve an expected effect, which seriously affects actual display quality of the image. Therefore, it is particularly important to improve the difference caused by a panel structure by over driving neighboring lines of sub-pixels through a line over driving (LOD) table.

LOD table adjustment method and LOD table adjustment system

TCL China Star Optoelectronics Technolog Co., Ltd.


In a printed board mounting method using a directional coupling bus for a high-speed data transfer, multi-bit data are transferred between nodes at a low cost. For this purpose, to transfer multi-bit data by directional coupling, a one-bit multi-coupling wiring network is vertically configured in a multilayered printed board. This minimizes the width of an area occupied by each bit along a wiring direction of the board to thereby implement a multi-bit configuration.

The present invention relates to a technology to transfer data between elements of a multiprocessor, a memory, or the like in an information processing system, for example, between digital circuits or functional blocks thereof including complementary metal-oxide semiconductors (CMOS), and in particular, to a technology to increase transmission speed of a data transfer bus in which a plurality of elements are connected to one transmission line.
JP-A-5-2239807 (De Veer et al; U.S. Pat. No. 3,619,504) describes a non-contact bus wiring which is a bus method to transfer data at a high speed between many nodes, for example, in a multiprocessor system. FIG. 3 shows a fundamental layout of the wiring in which data is transferred between two nodes using crosstalk, i.e., a directional coupler. That is, in this transfer technology, data is transferred between a bus master 10-1 and slaves 10-2 to 10-8 by means of crosstalk between two transmission lines, i.e., wiring 1-1 and 1-2 to 1-8. In this diagram, Rtt indicates a termination resistor. This circuit configuration is suitable for data transfer between bus master 10-1 and slaves 10-2 to 10-8, but is not suitable for data transfer between slaves 10-2 to 10-8.
To solve the problem, JP-A-8-188366 (PCT/JP97/03922 filed Oct. 29, 1997) describes a gap coupling bus system. FIG. 4 shows a basic circuit of this system. In the circuit configuration of this technology, data is transferred between nodes 11 to 16 by use of crosstalk signals in directional coupling sections (1-4 to 5-6) in which wiring lines 21 to 26 are coupled with each other as shown in FIG. 4.
xe2x80x9cPresent State and Problems of Build-Up Multi-Layer Wiring Board Technologyxe2x80x9d written in pages 463 to 468 of the xe2x80x9cJournal of the Society of Circuit Engineers of Japanxe2x80x9d describes a technology of printed wiring boards in which via holes of pad-on-via type are implemented at a low cost to increase the wiring density.
In the wiring technology of the gap coupling bus system of JP-A-8-188366, one-bit slave-to-slave transfer routes are arranged in a lattice layout to couple all nodes with each other (in a multi-coupling wiring network). However, this network is not suitable to transfer multi-bit data for the following reasons. To construct a one-bit multi-coupling wiring network, the printed wiring board includes two signal layers arranged in a direction of thickness of the board to form a coupling network in a horizontal direction of the board. This increases the wiring width of each one-bit wiring. That is, to achieve a one-bit transfer using a multilayered printed wiring board, there are required four layers including two signal layers for each bit and two shield layers. For example, to simultaneously transfer data including one-byte, i.e., eight bits, there are required at least 23 layers including 16 signal layers (two layersxc3x978 bits) and seven shield layers to decrease interference between the bits. Even a personal computer today has a data width of eight bytes. In some server apparatuses, the data width is 16 bytes. To implement such a server using the technology, there are required at least 184 layers (8 bytesxc3x9723 layers) for 8-byte data width and 368 layers (16 bytesxc3x9723 layers) for 16-byte data width. However, it is difficult to manufacture 100 or more layers at a low cost in the printed wiring board technology at present. Particularly, it is practically impossible to construct a printed wiring board at a low cost using material such as glass epoxy or aramid.
It is therefore an object of the present invention to provide a data transmission technology in which multi-bit data is transferred between nodes via directional coupling (crosstalk) using a printed wiring board to thereby transfer data at a high speed.
Another object of the present invention to provide a data transmission technology in which differential signals from a directional coupler formed in a printed wiring board are compared with each other such that errors can be detected by demodulating an output signal resultant from the comparison.
To achieve the object in accordance with a concept of the present invention, since multi-bit data is transferred by directional coupling, when a one-bit multi-coupling wiring network is configured, using a multilayered printed wiring board, in a direction vertical to a board surface of the printed wiring board, a multi-bit configuration can be implemented with a minimized width of wiring for one bit in a wiring direction of the board.
The present invention has aspects as follows.
In accordance with a first aspect of the present invention, there is provided a directional coupling bus system including a bus connected to a plurality of modules each including an interface circuit to transfer digital data and a printed wiring board connected to the modules. The system further includes a termination resistor for impedance matching termination of each lead signal line from the modules and directional couplers in lead wiring ranging from a first one of the module to the termination resistor, the couplers including portions of lead wiring respectively from second and subsequent ones of the modules, the portions having a length of, for example, 30 mm. There is also included via holes of non-through type to connect the coupler between the modules to communicate data therebetween.
In accordance with a second aspect of the present invention, in the directional coupling bus system of the first aspect, the directional coupler includes two adjacent lines in one signal layer enclosed between ground planes or layers, and the coupler is connected via the via holes of non-though type.
In accordance with a third aspect of the present invention, in the directional coupler of the system of the first aspect, the digital signals from the modules are differential signals and the signal transmission from a functional element on one side to a functional element on another side is conducted by directional couplers of differential type.
In accordance with a fourth aspect of the present invention, there is provided a printed wiring board. In the bus system of the third aspect, the differential directional coupler includes two signal layers, layers 1 and 2 enclosed with power planes or layers of a printed wiring board. Differential signal (drive signal) lines from the functional element are arranged in layer 1 to be parallel to each other. Differential signal (receive signal) lines to the partner functional element are arranged in layer 2 to be at positions vertically associated with the differential drive signal lines in layer 1.
In accordance with a fourth aspect of the present invention, there is provided a printed wiring board. The directional coupler of differential type in accordance with the third aspect includes one signal layer enclosed with power planes of a printed wiring board. Differential signal (drive signal) lines from the functional element are arranged in the signal layer to be parallel to each other. Differential signal (receive signal) lines to the partner functional element are arranged in another layer of the signal layer to be on both sides of the differential drive signal lines.
In accordance with a sixth aspect of the present invention, there is provided a printed board by using the printed wiring board of the fourth or fifth aspect in which n functional elements (n is equal to or more than two) are mounted on the board. There are arranged m signal layers, each of the layer includes two layers in pair or one layer to configure a directional coupler of differential type. Pairs of signal and ground planes are disposed on the board to set m=nxe2x88x921.
There are further arranged P directional couplers to transfer data between the n modules, where P=nxc2x7(nxe2x88x921)/2. The P directional couplers are alternately disposed in a direction of thickness of the board such that wiring from the modules configure one set of the P directional couplers for each other module.
In accordance with a seventh aspect of the present invention, in the directional coupling bus system of the first aspect, a receiver includes a differential comparator having hysteresis.
In accordance with an eighth aspect of the present invention, in the directional coupling bus system of the seventh aspect, there is provided a directional coupling bus system of source clock synchronous type in which a receiver receiving data and a clock signal includes a differential comparator having hysteresis and the data is latched by a signal obtained by shifting the clock signal 90xc2x0 in phase.
In accordance with a ninth aspect of the present invention, in the directional coupling bus system of the first aspect, the receiver includes two differential comparators each having a voltage offset in which one of the receivers has a positive offset and the other one has a negative offset.
In accordance with a tenth aspect of the present invention, in the directional coupling bus system of the ninth aspect, a receiver of data and a clock signal includes a differential comparator having hysteresis and the data is latched by a signal obtained by shifting the clock signal 90xc2x0 in phase.
In accordance with an 11th aspect of the present invention, for the directional coupling bus system of the tenth aspect, there is provided an error detection circuit in which a differential signal of data signals from the receiver is latched by a differential signal of clock signals of the receiver. A positive logic (H) signal and a negative logic (L) are represented as an up signal and a down signal, respectively. Using the up and down signals, the directional coupling bus system changes its state as up signal input changes from a logical low level (L) to a logical high level (H) that is, xe2x80x9cLxe2x80x9d to xe2x80x9cHtxe2x80x9d up signal input change from xe2x80x9cHxe2x80x9d level to xe2x80x9cErrorxe2x80x9d state down signal input changes from xe2x80x9cLxe2x80x9d to xe2x80x9cErrorxe2x80x9dup signal input changes from xe2x80x9cHxe2x80x9d to xe2x80x9cLxe2x80x9d. Data or an error signal is produced in accordance with the state transition.
In accordance with the 12th aspect of the present invention, the directional coupling bus system of the 11th aspect includes an error detection circuit.
In accordance with the 13th aspect of the present invention, by using the printed board of the sixth aspect of the present invention, there is provided a bus system including a printed wiring board in which the wiring density is increased by consecutively arranging the P directional couplers.

Directional coupling bus system using printed board