A method to generate a magnitude result of a mathematic operation of two decimal operands within one cycle in a decimal arithmetic logic unit structure, wherein the decimal operands are in hexadecimal sign magnitude format.

The invention relates to a method to generate a magnitude result of a mathematic operation of two decimal operands within one cycle in a decimal arithmetic logic unit structure, particularly wherein the decimal operands are in hexadecimal sign magnitude format, plus a decimal arithmetic logic unit structure to perform such a method.
Mainframe computers can increase the speed of decimal operations. For example, two operands X, Y to be added with or to be subtracted from each other are in a sign magnitude hexadecimal format. In sign magnitude hexadecimal format each digit i of the operands X, Y and of the result of the mathematic operation is represented by a four-bit code with the values '0' to '9' encoded as '0000' to '1001'. The hexadecimals 'A', 'C', 'E', 'F' indicate a positive algebraic sign, wherein 'B' and 'D' indicate a negative sign. Before an arithmetical operation takes place, the signs are removed from the operands, and it is decided whether an effective decimal addition or an effective decimal subtraction is being performed.
In case of an effective subtraction, the magnitude of the result can be less than zero, if the minuend X is smaller than the subtrahend Y. In this case, an additional cycle is necessary to re-complement the result into a sign magnitude format, as known in the art.
The general rule for binary decimal operations like additions (ADD) and subtractions (SUB) of two operands X, Y is as follows:ADD: S=X+Y+6digitwise
Thereby, if the digit carry-out (DCyOuti) of a digit i of the result S is zero, i.e. DCyOuti=0, then the digit i has to be corrected by subtracting six. Otherwise, the digit i is correct.SUB: S=A−B
Thereby, if DCyOuti=0, then the digit i is corrected by subtracting 6. Otherwise, digit i is correct. Further, if the carry-out (CyOut) of the most significant digit (MSD) on the left is zero, i.e. DCyOutMSD=CyOut=0, the result S is negative and must be re-complemented to get the magnitude M.
The procedure of a subtraction with negative result S is explained with reference to the following example.
Two decimal operands X=2856 and Y=5947 are subtracted from each other. The decimal result S has the magnitude M 3091 and is negative.
The digits 2856 of the operand X in hexadecimal are represented by the four-bit codes a, b, c, d
dcBaX:0010100001010110
with the digit 'a' as the least significant digit (LSD) and the digit 'd' as the most significant digit (MSD).
The digits 5947 of the operand Y in hexadecimal are represented by the four-bit codes
dcBaY:0101100101000111
To perform the subtraction, the two's complement of the inverted operand Y′ is added with the first operand X. To do so, first the operand Y is inverted bitwise to
dcBaY′:1010011010111000
To get the two's complement of the operand Y, further a carry-in (CyIn) of one, i.e. CyIn=1, is added to the least significant digit (LSD) 'a' on the right of Y′. Considering this, the subtraction X−Y is performed according to
dcBaX:0010100001010110+ Y′:+1010011010111000+ CyIn:+1wherein the following DCyOuti are generated by the digitwise addition
dcBaDCyOuti:0010
The DCyOuti of the digits i are used as digit carry-in (DCyIni+1) for the next higher digits i+1 to the left according to:
dcBaX:0010100001010110+ Y′:+1010011010111000+ CyIn:+1+ DCyIni + 1:+0010=1100111100001111
Thereby, any DCyOuti=0 indicates a digitwise minus six correction for the particular digit according to
dcBaX:0010100001010110+ Y′:+1010011010111000+ CyIn:+1DCyIni + 1:+0010=1100111100001111DCyOuti:0010− 6:+101010101010iR:=0110100100001001decimal:6909with the intermediate result iR. The result of the operation includes an intermediate result iR since the DCyOuti of the digit 'd' on the left that is the MSD is zero. The DCyOuti of the digit 'd' is the CyOut. CyOut=0 indicates a recomplementation of the result of the operation performed to obtain the magnitude M of the result S of the subtraction.
To do so, a second cycle is performed, wherein the first operand X is zero and the second operand Y is the intermediate result iR:
dcBa 0000:0000000000000000− 6909:+1001011011110110CyIn:+1=1001011011110111DCyOuti:0000  − 6:+1010101010101010M:=0011000010010001decimal:3091
To perform such operations within a microprocessor, a decimal arithmetic logic unit structure (ALU) ALU1 as shown in FIG. 1 is used. FIG. 1 shows an embodiment of a carry select structure which known in the art. However, the sum can be achieved with any other adder structure which achieves the performance requirements.
Two decimal operands X, Y, minuend X and subtrahend Y, are provided by registers R1, R2. The register R1 is connected with a first input of a digit carry network DCN and with first inputs of two pre-sum logics P1, P2. The output of the register R2 is connected to the input of an inverter I and with an adder A1 in parallel to the inverter I. The inverter performs a bitwise inversion of the operand Y. The adder A1 performs a digitwise +6 addition of the operand Y that is needed for effective decimal additions.
The output of the inverter I is connected to a first input of a first multiplexer M1. The output of the adder A1 is connected to a second input of the first multiplexer M1. A signal EDA indicating an effective decimal addition is used to select the second input of the multiplexer M1 as an output. The orthogonal signal of EDA, indicating an effective decimal subtraction is used to select the first input of the multiplexer M1 as an output. The signal EDA is generated by an operation decoder (not shown). The signal EDA and its mutual exclusive signal EDS (effective decimal subtraction), can be generated by inverting the other. The output of the multiplexer M1 is connected to a second input of the digit carry network DCN and to the second inputs of the two pre-sum logics P1, P2.
The digit carry network DCN operates according to conventional carry look ahead techniques by using generate and propagate functions of the operand bits to generate the CyOut of the MSD. Furthermore, the digit carry network DCN generates DCyOuti, i.e. DCyIni+1, for each of the decimal digit positions. The digit carry network DCN further has a third input. The signal EDA is inverted and fed to said third input. The inverted signal EDA indicates CyIn=1 for the LSD which is needed to generate the two's complement of the subtrahend Y for performing subtractions.
The pre-sum logics P1, P2 have third inputs each, wherein the third input of the pre-sum logic P1 is fed with an input of '0' and the third input of the pre-sum logic P2 is fed with an input of '1'. Depending on the operand version received, the pre-sum logic P1 generates from the operands digitwise preliminary results X+Y+6 or X−Y on the assumption that DCyIni+1=0 and the pre-sum logic P2 generates from the operands digitwise preliminary results X+Y+6 or X−Y on the assumption that DCyIni+1=1.
The pre-sum selection is performed by a second multiplexer M2 which selects one of the pre sums X+Y+6 and X−Y digitwise, depending on DCyIni+1 provided by the digit carry network DCN into the digit position shown.
The structure of FIG. 1 is also known as Carry Select Adder Structure. It can be of any type, e.g. a Carry Propagation Structure CPA. As known in the art, only the digitwise +6 and −6 feature is required, but the carry network and the preliminary sum can be generated with any appropriate known structure.
The following describes a configuration having only the path of one digit. The complete width of the result is formed of several digits, e.g. 8 digits. The output of the second multiplexer M2 is split into two parallel paths. The first path is directly connected to a first input of a third multiplexer M3. The second path leads to a second adder A2 that performs a digitwise −6 correction. The result of that digitwise −6 correction is fed to a second input of the third multiplexer. Depending on the appropriate DigitCyOut of the digit carry network DCN, one of the two inputs of the third multiplexer M3 is selected as an output. If DigitCyOut=1, the second input is selected, i.e. no correction needed. If DigitCyOut=0, the first input is selected, i.e. the digit has to be corrected by subtracting 6. If the CyOut of the MSD is 1, the output of all digits of the third multiplexer M3 is the magnitude M of the complete result. If the CyOut of the MSD is 0, the output of the third multiplexer M3 is the intermediate result iR that has to be recomplemented in order to get the magnitude M of the result S. To recomplement the intermediate result iR a second cycle has to be performed within the same hardware structure, with X=0 and Y=iR.
FIG. 3 shows another conventional decimal arithmetic logic unit structure ALU2 which, compared to the decimal arithmetic logic unit structure of FIG. 1, is enhanced to additionally perform binary mathematic operations. Thereby the same reference numerals are used as in FIG. 1. The enhancement is achieved by a substitution of the inverter I in FIG. 1 by a XOR-gate XO. Furthermore logic within the Block CDDC in FIG. 3 controls the switching levels of the multiplexer M3. For binary operation always the second level of this multiplexer M3 is active. In case of an effective decimal addition the operand Y provided by the register R2 runs via the adder A1. In case of an effective subtraction, binary as well as decimal, the operand Y runs via the XOR-gate XO in order to be inverted. This is controlled by a general subtraction signal any_Sub AS. This signal any_Sub AS can also be used as CarryIn for the DCN in order to achieve the two's complement within the DCN. If a binary operation is performed, no correction occurs at the third multiplexer M3.
Improvements to the structure of FIG. 1 are known, for example, as described in U.S. Pat. No. 5,944,772 and US 2006/0031279 A1. However, such improvements are directed to the reduction of the path delay. All known structures require an additional cycle in case of negative results to obtain the magnitude.

Method and decimal arithmetic logic unit structure to generate a magnitude result of a mathematic

International Business Machines Corporation


An electronic device is provided with: a first electronic circuit, integrated in a first die; a second electronic circuit, integrated in a second die; and a galvanic isolator element, designed to insulate galvanically, and to enable transfer of signals between, the first electronic circuit and the second electronic circuit. The galvanic isolator element has: a transformer substrate, distinct from the first die and from the second die; and a galvanic-insulation transformer formed by a first inductive element, integrated in the first die, and by a second inductive element, integrated in the transformer substrate and so arranged as to be magnetically coupled to the first inductive element.

1. Technical Field
The present disclosure relates to a semiconductor electronic device provided with an integrated galvanic isolator element, in particular for the insulated transfer of data and/or power signals between two electronic integrated circuits, and to a related assembly process.
2. Description of the Related Art
As is known, many electronic applications transfer signals, which convey some sort of information, or electric power or energy, between two distinct electrical/electronic circuits, without any electrical connection by metal conductors between the same circuits (i.e., without a passage of electrical current occurring through an ohmic connection path). In other words, such applications include two distinct electronic circuits that communicate without contact, being "galvanically" insulated from one another.
For example, a galvanic insulation is commonly used in medical apparatuses (for example, for protecting users from electrical discharge), in applications for industrial automation (for example, for separating the parts operating at high voltage/power from the control parts, or for preventing destructive "ground loops" in the case of interconnections with different ground potentials), or in automotive applications (for example, in the production of electric engines for hybrid vehicles), or in consumer electronics (for example in the production of insulated AC/DC or DC/DC converters).
One of the two electronic circuits, and in particular the corresponding conductive portions at the reference potential, can be at a potential even markedly different from the corresponding portions of the second electronic circuit. This potential difference may also be variable, thus preventing the possibility of using a single common conductor with respect to which the signals are referenced. Finally, there are applications that guarantee an insulation between two electronic circuits (even for voltages of up to some kilovolts), which cannot be achieved with "level shifter" type solutions, in so far as a complete insulation would not be achieved and providing semiconductor components with operating voltages that are so high would become difficult and costly.
Numerous solutions have been proposed for obtaining galvanic isolators in integrated technology (i.e., by using the manufacturing techniques of the semiconductor industry or, in general, of microelectronics). Generally, integrated galvanic isolators are currently divided into three main classes, according to the operating principle adopted.
A first class includes optical couplers, which envisage transmission of signals by using light radiation through a medium transparent thereto, and in particular using a LED-phototransistor pair for carrying out a double electro-optical conversion, in transmission and reception. The main problems linked to this class of isolators are due to the low efficiency of the manufacturing process and to the limited data transfer rate (the so-called "bit rate") that can be achieved, given by the signal conversion, mentioned above, from the optical domain to the electrical domain, and vice versa. In addition, it is known that generally the performance of optical couplers are bound to undergo degradation over time.
Belonging to a second class are capacitive-coupling isolators, in which the galvanic insulation is guaranteed by the presence of an appropriate dielectric set between two conductors (which provide the plates of a capacitor). Capacitive-coupling isolators, albeit enabling high transfer rates to be achieved, are limited by a reduced immunity to voltage transients (the so-called dV/dt), which occur for example when the difference of potential between the two electronic circuits to be insulated varies suddenly; these transients cause generation of high currents that are potentially destructive. Furthermore, this type of isolators does not enable transfer of the d.c. content of the signals, and in particular does not enable transfer of electric power.
The third class includes isolators, envisaging the use of variable magnetic fields for the transfer of signals, and in particular use of a coupling of an inductive, or magnetic, type.
Belonging in this class are, for example, isolators based upon the giant-magnetoresistive (GMR) effect. In these isolators, a first circuit implements a coil driven by a generator, the current of which represents the signal to be transferred (for example, by appropriate modulations), for generating a variable magnetic field. The magnetic field modulates the resistance of magnetoresistive sensors in a second circuit, which is to be insulated with respect to the first. The resistance variation of the magnetoresistive sensors, appropriately arranged in a bridge circuit configuration, produces a voltage that reproduces the transmitted signal. The galvanic insulation is ensured by the insulating material that physically separates the two circuits.
Other isolators, based upon inductive coupling, use a transformer for carrying out insulated transmission of signals between a first electronic circuit and a second electronic circuit. In general, these isolators envisage the use of two coils of conductive material, for example metal, set in the proximity of one another and separated by an appropriate dielectric medium; the coils provide the primary and secondary windings of a transformer, for the insulated transfer of data and/or power signals.
Advantageously, given that it is an intrinsically symmetrical system, a transformer can be operated in reverse to transfer information from the secondary winding to the primary winding, thus enabling provision of a bi-directional system. Furthermore, galvanic isolators based upon inductive coupling enable high transfer rates to be obtained, maintaining a high insensitivity to common-mode transients.
Various solutions have so far been proposed for integrated implementation of transformers for galvanic insulation.
For example, U.S. Pat. No. 7,064,442 and US 2008/0179963 disclose respective electronic devices, comprising in general, and as illustrated schematically in FIG. 1: a first electronic integrated circuit (IC) 2 and a second electronic integrated circuit (IC) 3 (operating, respectively, as "transmitter" and "receiver" of the signals to be transferred), integrating respective electronic components, provided respectively in a first die 4 and in a second die 5 of semiconductor material; and moreover a transformer 6, entirely integrated in a third die 7, which is also made of semiconductor material, for example silicon and set between the dice 4, 5 of the first and second electronic integrated circuits 2, 3, so as to provide the galvanic insulation required between the circuits. The first, second, and third dice 4, 5, 7 are assembled within one and the same package, designated as a whole by 8, and appropriate electrical-connection structures 9 are provided, for example with wire-bonding techniques (i.e., with the use of connection wires), between a primary winding 6a of the transformer 6 and the first electronic integrated circuit 2, and between a secondary winding 6b of the same transformer 6 and the second electronic integrated circuit 3.
The transformer 6 can be formed in the corresponding third die 7, with a "vertical" process, that is, the primary 6a and secondary 6b windings are separated vertically by an appropriate dielectric layer; or with a "horizontal" process, that is, the conductive portions defining both the primary winding 6a and the secondary winding 6b are provided a same surface of a dielectric layer. The latter solution can be, however, disadvantageous in so far as the insulation between the primary winding and the secondary winding of the transformer must be in this case guaranteed not only through the thickness of the dielectric layer, but also on the surface of the same dielectric layer.
In general, the aforesaid solution for providing the galvanic-insulation transformer has some drawbacks linked to the need of envisaging complex electrical-connection structures 9 for the electrical connection of the various distinct parts of which the corresponding electronic devices are made up, and moreover linked to the occupation of area within the package.
A further solution of a known type for providing a transformer as galvanic isolator envisages the use of just two dice of semiconductor material, as schematically illustrated in FIG. 2.
In particular, in a first die, once again designated by 4, the first electronic integrated circuit 2 is provided, for example operating as a transmitter of the signals to be transferred. Instead, both the second electronic integrated circuit 3, having functions of receiver, and the transformer 6, designed to provide the galvanic insulation between the first electronic integrated circuit 2 and the second electronic integrated circuit 3, are provided in a second die 5, set so as to be physically distinct and insulated from the first, but for appropriate electrical connections (for example, provided with the wire-bonding technique). The first and second dice 4, 5 are conveniently assembled within a single package.
In greater detail, the second electronic integrated circuit 3 (shown schematically in FIG. 2 as comprising a plurality of doped regions 3a) is provided with standard processing techniques (for example of a CMOS type, referred to as "baseline CMOS processing", or of a DMOS type) in a structural layer 10 of the second die 5. A passivation layer 11, of dielectric material, is formed on the structural layer 10; within this passivation layer, various metal levels are provided, of which FIG. 2 shows by way of example only a bottom metal level 12 (set in the proximity of the structural layer 10), and a top metal level 13 (set at a distance from the same structural layer 10).
The metal levels, appropriately connected vertically to one another, provide electrical connections towards the second electronic integrated circuit 3. Furthermore, portions of the top metal level 13, appropriately shaped like a coil, provide the secondary winding 6b of the transformer 6.
An insulating layer 14, made of dielectric material, for example polyamide, having a given thickness, is provided on the top metal level 13 and the passivation layer 11; the primary winding 6a of the transformer 6 is provided on the outer surface of the insulating layer 14 (not in contact with the underlying layers), set vertically in a position corresponding to the secondary winding 6b, for example formed with techniques of deposition of a conductive layer (such as, for example, gold). The primary winding 6a is electrically connected to the first electronic integrated circuit 2 in the first die 4, by means of electrical-connection structures 9, for example including connection wires.
The aforesaid insulating layer 14 is deposited on the passivation layer 11, for example by deposition from liquid precursor. In addition, the insulating layer 14 is appropriately removed at the electrical contacts towards the second electronic integrated circuit 3 so as to enable electrical connection thereof towards the outside world by means of appropriate connection elements 15 (for example, once again with the wire-bonding technique).
Although presenting some specific advantages, for example in terms of a reduction of the overall dimensions and of the complexity of the electrical connections, this solution is not free from disadvantages either, some of which afflict in general the known embodiments proposed so far.
In particular, manufacturing of the transformer 6 requires appropriate post-processing steps, which are carried out on top of the structural layer 10 in which, in this case, the second electronic integrated circuit 3 has already been formed. This post-processing may consequently damage the underlying integrated circuit, for example on account of the thermal cycles associated thereto, and in general entails an increase in the complexity and manufacturing costs of the resulting electronic devices.
Furthermore, the characteristics of galvanic insulation of the transformer 6 are linked in this case to the intrinsic and geometrical characteristics of the insulating layer 14, physically set between the primary and secondary windings 6a, 6b of the transformer 6.
However, the post-processing techniques enable thicknesses of insulating material to be achieved that are not greater than a given threshold (for example, having a typical value not greater than 20 μm), thus representing a very precise limit for the maximum insulation voltage that can be achieved.
A further solution for providing a galvanic insulation between two integrated circuits of an electronic device, proposed by the present applicant and described, for example, in EP-A-1 990 914, envisages use of appropriate modulation/demodulation techniques for transmitting a radio-frequency signal from a first micro-antenna set on a first integrated circuit to a second micro-antenna positioned on a second integrated circuit. The two integrated circuits, and the respective micro-antennas, are provided in respective dice of semiconductor material, which can be arranged on one another within one and the same package in such a way as to enable communication between the micro-antennas.
This solution enables high transfer rates to be achieved, with reduced costs and manufacturing complexity; however, the transferred signals may at times be weak on account of the losses induced by the substrates of the aforesaid dice that are set between the micro-antennas. Furthermore, the modulation/demodulation techniques require the use of dedicated transmitter/receiver circuits, entailing an increase of the circuit complexity.
Another galvanic isolation arrangement is shown in US 2010/0265024 to Nakashiba. In Nakashiba, an interconnect substrate, on which a second inductor of a transformer is made, is attached on both of first and second dice by solder balls (having a diameter of around 20 μm). This arrangement involves technical difficulties and limitations that make it unsuitable for production on an industrial level.
First, the distance laterally separating the two dice determines the electrical insulation between the two dice, and therefore is a parameter that must be controlled closely. A first limitation is that this distance cannot be high (contrary to what would be desired for the electrical insulation), to avoid unnecessary increasing the lateral size of the interconnect substrate (and all connections carried by the same substrate). Therefore, placing the interconnect substrate on the two dice requires simultaneous accurate control of all these parameters:
distance between the dice;
alignment between the electrical contacts between the interconnect substrate and the first die; and
alignment between the electrical contacts between the interconnect substrate and the second die.
Since alignment of dice is independent of the subsequent placement of interconnect substrate, a maximum tolerance of 14 μm is allowed during manufacturing (considering a diameter of 20 μm for the solder balls). This level of precision is extremely difficult at the industrial level.
Moreover, when the first and second dice are placed on respective lead frames, the distance between the frames will be similar to the distance between the dice, with possible problems of electrical insulation between the frames.
In Nakashiba, also the vertical alignment between the two dice (in particular between the respective front surfaces) is also a source of problems, since it may lead to inclination of the interconnect substrate due to the different thicknesses of the first and second dice (the thickness of a die cannot be typically controlled with repeatability and precision lower than 10 μm), and also to the different thickness of the die attach materials.
A further point to consider is how the insulation between the inductors in the transformer is achieved in Nakashiba. In Nakashiba, the interconnect substrate is simply, as the name suggests, a connecting structure and does not influence the galvanic insulation properties. In Nakashiba, insulation is provided by the separation distance between the dice and by the thickness of the dielectric stack in the first die. Because of this, the first inductor in the first die has to be made in the lower metal layers, and this is per se not advantageous, since these metal layers are those with highest resistivity and low current density. Accordingly, this implies further difficulties in having transformers with high Q and efficiency.

Semiconductor electronic device with an integrated device with an integrated galvanic isolator element and related assembly process


Described is an ABS for vehicles in which all wheels are driven. Of particular concern is the forming of a final reference speed for the slip control. From the speeds of wheels with different speeds, an auxiliary reference speed, and a reference speed and a final reference speed for the slip control is formed . In the event of instability, however, the increase of the auxiliary reference speed determines the reference speed.

From DE-A1 3706 514, a method is known to determine, in a vehicle with a two-wheel drive, the reference speed for the development of a slip signal, other than by the control, through the speed of the slower of the non-driven wheels. In the event of instability, the increase of an auxiliary reference speed, which is determined, other than by the control, through the speed of the faster of the non-driven wheels, determines the reference speed.


A primer composition for a fluorinated elastomer or a fluorinated gel, said primer composition comprising:                100 parts by weight of (a) a linear perfluoro polyether compound having at least two alkenyl groups per molecule, a perfluoro polyether backbone having repeating units represented by the formula, —CaF2aO—, wherein a is an integer of from 1 to 6, and a weight average molecular weight of from 5,000 to 100,000,        (b) an organosiloxane compound having one or more fluorine atom and at least two SiH bonds per molecule, in such an amount that a molar ratio of the SiH bond in the organosiloxane compound to the alkenyl group in Component (a) ranges from 0.8 to 5.0,        a catalytic amount of (c) a hydrosilylation catalyst,        5 to 100 parts by weight of (d) an organosiloxane compound having, per molecule, at least one SiH bond and at least one epoxy group and/or trialkoxysilyl group bonded to a silicon atom of said organosiloxane via an organic group which may have an oxygen atom, and100 to 10000 parts by weight, per total 100 parts by weight of said components (a), (b), (c) and (d), of (e) an organic solvent having a fluorine atom and a boiling point of not higher than 150° C. at atmospheric pressure.

A heat curable elastomer or gel composition mainly composed of a polymer having at least two alkenyl groups per molecule and a perfluoro polyether backbone gives a cured product which is highly resistant to heat, chemicals, solvents and water. The cured product also has a good releasing property and, naturally, does not adhere to a substrate well.
To improve adhesion of the aforesaid compositions without sacrificing their good properties, a primer may be applied to a substrate before applying the compositions.
Various primers are commercially available, for example, a silane primer mainly composed of a silane coupling agent, and a primer mainly composed of a polymer such as a synthetic rubber, acrylic resin, urethane resin, or epoxy resin. However, these primers do not bond the aforesaid heat curable elastomer or gel composition satisfactorily because they have poor affinity with the composition, so that they do now wet the compositions well at the interface between the primer and the composition.
A heat curable fluorinated elastomer and a heat curable fluorinated elastomer gel compositions are known which have improved adhesion by containing components which function like primers.
For example, Japanese Patent Application Laid-Open No. H9-95615 discloses a heat curable fluorinated composition comprising (A) a fluorine-containing amide compound having vinyl groups at both ends and a perfluoropolyether backbone, (B) a fluorine-containing organohydrogensiloxane having at least one perfluoroxyalkyl, perfluoroalkyl, perfluoroxyalkylene or perfluoroalkylene group and two hydroxysilyl group per molecule, (C) a catalytic amount of a platinum metal compound, and (D) an organosiloxane having at least one epoxy group and/or trialkoxysilyl group bonded to a silicon atom via a carbon atom or a carbon atom and an oxygen atom. A cured product is resistant to solvent, chemicals, heat and a low temperature and humidity. Further, by heating at a relatively low temperature for a relatively short period of time, the composition gives a cured product strongly adhered to a metal or plastic.
Japanese Patent Application Laid-Open No. 2001-72868 discloses a curable fluorinated elastomer composition comprising, in addition to the aforesaid components (A) to (D), a carboxylic acid anhydride. Cured composition adheres well to various kinds of substrates, especially to PPS and polyamide and therefore useful as an adhesive for articles such as a case made of PPS or polyamide.
Japanese Patent Application Laid-Open No. 2002-105319 discloses a curable composition comprising, in addition to the aforesaid components (A) to (D), (E) an organosiloxane having at least one SiH bond, at least one cyclic carboxylic acid anhydride residue bonded to a silicon atom via a carbon atom, or at least one perfluoroxyalkyl group or perfluoroalkyl group bonded to a silicon atom via a carbon atom per molecule. Cured composition adheres well to various kinds of substrates, especially to PPS, polyamide, and polyimide and therefore useful as an adhesive for articles such as automobile parts, electric or electronic parts made of these plastic.
Japanese Patent Application Laid-Open No. 2002-194220 discloses a curable gel composition which strongly adheres to a substrate when cured. The composition comprises, in addition to the aforesaid components (A) to (D), (E) a carboxylic acid anhydride. Cured composition, which is a fluorinated gel, adheres well to various kinds of substrates, especially PPS and PBT and therefore useful as adhesive for articles such as a case made of PPS or PBT.
The aforesaid heat curable elastomer or gel compositions can be bonded to various substrates such as metals, glass, ceramics and plastics, by containing adhesion-enhancing components having an alkoxysilyl group, an epoxy group, a carboxyl group or acid anhydride residue.
However, these adhesion-enhancing components, when contained in a fluorinated elastomer, tend to degrade mechanical strength or compression permanent set of the elastomer. In a heat curable fluorinated gel, these components tend to change hardness, determined by penetration of a needle, of a cured product with time, indicating that the cured product hardens to be more brittle.

Primer composition for a fluorinated elastomer or a fluorinated gel


In one general aspect, a tunable electromagnetic metamaterial as described herein includes a substrate and an array of split ring resonators formed on the substrate. At least one of the split ring resonators is a capacitively tuned split ring resonator. The capacitively tuned split ring resonator includes a structure having a gap and is formed of an electrically conductive material. The capacitively tuned split ring resonator also includes a region of photo-capacitive material formed in close proximity to the structure such that the capacitance of the metamaterial is changed when illuminated by controlling electromagnetic radiation having a selected range of wavelengths.

Artificial resonant structures known as split ring resonators (SRRs) can be designed to produce a negative effective magnetic permeability μeff in a fixed, narrow frequency band. A circuit made of a conducting trace or wire with a gap will operate analogously to a resonant circuit consisting of a resistor (R), an inductor (L), and a capacitor (C)—i.e., an RLC circuit. The physical dimension, "a," of the circuit typically is such that a<<λ, where λ is the wavelength of the subject electromagnetic radiation of interest.
Periodic arrays of SRRs have been combined with periodic arrays of straight wires to yield an effective electric permittivity ∈eff (dielectric constant) that can be engineered to have specific values in a frequency band of interest. The quantities μeff and ∈eff are the relative permeability and permittivity—the actual values are obtained by multiplying μeff and ∈eff by the vacuum values of μ0 and ∈0 respectively. The combined effective permittivity and permeability result in an effective index of refraction, neff, where neff=(μeff∈eff)1/2, that can possess values not found in naturally occurring materials or blends of naturally occurring materials. In particular, if μeff and ∈eff are both negative then neff will be negative.
Materials having a negative neff are referred to as "left-handed materials" (LHM) or negative index materials (NIM). A NIM has some remarkable properties. For example, in a NIM the direction of refraction is opposite that of normal materials and the Doppler effect shifts frequencies in the opposite direction compared to normal materials. A NIM is one particular example of an engineered electromagnetic material, but other examples exist. Such engineered electromagnetic materials are referred to as electromagnetic "metamaterials." Metamaterials are designed to have properties that are not found in the constituent materials and are not typically found in nature. The special electromagnetic properties of the metamaterial result mainly from its geometrical structure.
It is desirable to make an effective metamaterial that can be actively tunable with values of effective magnetic permeability and permittivity not achievable by other methods or materials. It also is desirable to make an effective metamaterial that can be employed in a wide range of device applications and over a wide range of subject electromagnetic radiation frequencies.

Actively tunable electromagnetic metamaterial

The United States of America as represented by the Secretary of the Navy


A method, system, and program for managing use of experts by callers waiting within a hold queue are provided. First, a call on hold in a hold queue is transferred to an expert system responsive to a request by the caller to speak with an expert. Then, responsive to detecting an answer by a party at the expert system, an authentication of the identity of the answering party is required. If the authenticated identity of the answering party matches an expected expert identity, then the call is connected to the expert, such that the expert is required to authenticate an identity before providing service to a call from the hold queue.

1. Technical Field
The present invention relates in general to telecommunications and, in particular, to call hold centers. Still more particularly, the present invention relates to managing use of experts by callers waiting within a hold queue.
2. Description of the Related Art
Many companies provide telephone-based access to help staff, sales personnel, representatives, and automated menus via a call center. Where high telephone call traffic is typical in telephone access to a company's representatives, a PBX system receives the call and distributes the call to an automatic call distributor (ACD), thus incorporating a hold function in the call center. ACDs are often employed to provide an even and systematic distribution of incoming calls to multiple representatives. In particular, ACDs typically provide incoming calls with a direct connection to an available representative until all representatives are busy. Then, calling parties are placed in a call queue, and selectively connected to a representative once a representative comes available.
Call queues may cause frustration and ill will of consumers towards a company, particularly where excessively long waits, full queues and accidental disconnects are encountered. In order to alleviate frustrations, before a call is placed in a hold queue, a greeting message identifying the called party is played by the ACD, via an interactive voice response unit (IVRU), to the caller, indicating that the next available agent will service the call. During the holding period, music or advertising messages may be played to the caller to entertain or inform the caller of sales promotions for particular products or services. More enhanced ACD systems may offer additional services to callers, such as news, multiple selections of music, release to make additional phone calls, games while on hold, and other services that make on hold time more pleasant.
Alternatively, enhanced ACD systems may attempt to provide a caller with the information needed without the caller having to wait to speak with a representative. For example, an ACD system may allow a caller waiting in a call queue to monitor(but not participate in) other caller conversations with similar queries. In addition, an ACD system may allow a caller waiting in a call queue to listen to previous conversations with representatives with similar queries. However, while these features may provide information to a caller, the caller is still limited to hearing conversations of other callers and not receiving a direct answer to the caller's own question. Where that direct answer is still needed, the caller must still wait for an available representative.
Therefore, in view of the foregoing, it would be advantageous to provide a method, system, and program for placing a call on hold in a first queue in a call center, but allowing a caller to select to speak with an expert while waiting on the call to be answered by a representative of the call center. By speaking with an expert, it is hoped that a caller's question would be answered and the caller would not need to wait in the hold queue.

Managing use of experts by callers waiting in a hold queue


A new low-power test compression method and design for testability (DFT) architecture are proposed for deterministic test pairs for launch-on-capture (LOC) transition fault testing by using a new seed encoding scheme, a new low-power test application procedure and a new test compression architecture. The new seed encoding scheme generates seeds for all test pairs by selecting a primitive polynomial that encodes all test pairs of a compact test set. The low-power test compression architecture includes: (1) the LFSR established by the selected primitive polynomial and the selected number of extra variables injected to the LFSR; (2) the scan tree architecture for LOC transition fault testing; and (3) the new gating technique. A new static test compaction scheme is proposed by bitwise modifying the values of a seed and the extra variables. A new technique for test point insertion is proposed for LOC delay testing in the two-frame-circuit model, which apparently reduces test data volume.

TABLE 1ATPG results for single stuck-at faults and LOC delay testingdetails of the circuitsstuck-at teststransition testcircuitsPIsPOsFFsgatesvecFCMAXCPU(s)vecFCMAXCPU(s)b1924306,642225,800154698.8036593560965284.47405311246ethernet9411513,715105,37190699.2019311480350199.3921597616vga_lcd8710917,079153,66498099.4058842940904599.64603214110netcard1564697,796568,986226099.10737146802781097.52960935220
Test data volume for LOC transition fault testing is far more than that of single stuck-at testing. Table I presents test generation results for LOC transition fault testing and single stuck-at fault testing. The columns with vec, FC and MAX represent the number of tests, fault coverage, and the number of maximum care bits for the whole test set, respectively. It is found that the number of test vectors for LOC transition fault testing is far more. The maximum number of care bits for single stuck-at tests is also apparently less than that for LOC transition fault testing. It is important for us to present an effective method for LOC transition fault test compression. Scan chain designs are used for both single stuck-at fault testing and LOC transition fault testing.
The current commercial EDA tools cannot handle test compression for LOC delay testing well. Excessive test power dissipation of test power has been a severe problem, which is even more difficult to handle for LOC delay testing. The huge amount of test data for delay testing makes test compression for delay testing even more important than that for stuck-at fault testing. Test application of compressed test data produces further more test power. Therefore, there is a strong need for an effective low-power test compression approach.
In this invention, we propose a new low-power test compression architecture for LOC-based transition fault testing. We present the major contributions of this invention as follows: (1) the LFSR established by the selected primitive polynomial and the selected number of extra variables injected to the LFSR; (2) the scan tree architecture for LOC transition fault testing; and (3) the new gating technique. (4) A new static test compaction scheme is proposed by bitwise modifying the values of a seed and the extra variables. (5) A new technique for test point insertion is proposed for LOC delay testing in the two-frame-circuit model, which apparently reduces test data volume.
Most of the previous deterministic BIST approaches did not include low-power concerns. We intend to present a new method that effectively combines an efficient low-power test application scheme for LOC delay testing. Power consumption for delay testing is an even more difficult problem because of a much larger number of delay test patterns. We propose a low-power test compression approach for LOC transition fault testing by using new a DFT architecture, test application scheme, seed modification and test point insertion technique.
As for the DFT architecture, our method introduces a new primitive polynomial selection method, and a new scheme to select the number of extra variables. Using the proposed DFT architecture, all deterministic test pairs can be encoded into a seed with a sequence of extra variables injected into the LFSR.
Test point are inserted into the circuit by reducing the potential care bits for each deterministic test pairs. This is implemented by using a cost function for LOC transition fault testing. Extra pins of the control points are connected to the PPIs or PIs in the two-frame circuit model by circuit structural analysis.
In order to further reduce test data volume, we propose a new seed modification technique. The seed modification technique can remove some seeds by revising the calculated values of the extra variables and the seed for each test pair. The seed modification technique is implemented by complementing value of each bit for the seed and extra variables, which removes some seeds and reduces test data volume without any additional control data. A new test point insertion placement scheme is proposed to compress test data volume based on the influence-cone based testability measure for LOC transition fault testing. Test point insertion is to reduce the number of care bits to detect faults. The extra pin of a control test point is connected to a pseudo-primary input (PPI). Extra pins of multiple control test points can share the same PPI. The pin overhead can be well-controlled based on the above scheme.

This patent is subject to a terminal disclaimer.

Low-power test compression for launch-on-capture transition fault testing


A method for making packets of nanostructures is presented. The method includes etching trenches in a silicon substrate. Nanostructures are grown in the trenches. The trenches are then filled with a filler material. Any filler and/or nanostructures material extending beyond the trench is removed. The silicon substrate is etched away, resulting in a nanopellet surrounding the nanostructures and wherein each nanostructures has a generally uniform length and direction. Nanostructures can comprise nanotubes, nanowires and nanofibers. The method eases the manipulation of nanostructures while providing geometrical uniformity.

As is known in the art, there has been a trend to develop materials at the nanoscale level. Manufacturing of nanoscale level devices is a challenge that needs to be addressed before the potential of nanotechnology becomes a reality. Manufacturing is defined as the transformation of materials and information into goods for the satisfaction of customer needs. Conventional manufacturing strives to produce goods in large volume with high quality, fast production rate, low cost and reasonable flexibility to accommodate the varying requirements of the customers. These attributes are equally applicable to the manufacturing of nanoscale products.
One type of nanoscale product comprises carbon nanotubes (CNTs). A carbon nanotube can be thought of as a hexagonal network of carbon atoms that has been rolled up to make a seamless cylinder. The cylinder can be tens of microns long, and each end is "capped" with half of a fullerene molecule. Single-wall nanotubes (SWNTs) can be thought of as the fundamental cylindrical structure, and these SWNTs form the building blocks of both multi-wall nanotubes and ordered arrays of single-wall nanotubes called ropes.
One method of forming a carbon nanotube comprises taking a sheet of graphite and reducing the size of the sheet such that the sheet becomes an extremely narrow strip of material. At a width of approximately 30 nanometers the strip curls about a lengthwise axis and the opposing carbon bonds at the side edges of the strip join to form a tube approximately 10 nanometers in diameter. Thinner tubes having a diameter of between 10 nanometers and 5 nanometers can be formed in the same manner. It is also possible to produce multiwall carbon nanotubes (MWNTs) by curving a number of sheets of graphite (typically 3 to 8 sheets) in a similar manner as forming a single wall carbon nanotube.
CNTs may also be prepared by laser vaporization of a carbon target in a furnace at approximately 1200° C. A cobalt-nickel catalyst helps the growth of the nanotubes because the catalyst prevents the ends of the CNTs from being "capped" during synthesis, and about 70-90% of the carbon target can be converted to single-wall nanotubes. While multi-wall carbon nanotubes do not need a catalyst for growth, single-wall nanotubes are preferably grown with a catalyst.
A carbon-arc method to grow arrays of SWNTs has also been developed. In this method, ordered nanotubes are produced from ionized carbon plasma, and joule heating from the discharge generated the plasma. In a scanning electron microscope (SEM), the nanotube material produced by either of these methods looks like a mat of carbon ropes. The ropes are between 10 and 20 nm across and up to 100 μm long. When examined in a transmission electron microscope (TEM), each rope is found to be comprised of a bundle of single-wall carbon nanotubes aligned along a single direction. X-ray diffraction, which views many ropes at once, shows that the diameters of the single-wall nanotubes have a narrow distribution with a strong peak.
The unique electronic properties of carbon nanotubes are due to the quantum confinement of electrons in a direction which is normal to the direction of a central longitudinal axis of the nanotube. In the radial direction, electrons are confined by the monolayer thickness of the graphite sheet. Around the circumference of the nanotube, periodic boundary conditions come into play. Because of this quantum confinement, electrons can only propagate along the nanotube axis, and so their wavevectors point in this direction. The resulting number of one-dimensional conduction and valence bands effectively depends upon the standing waves that are set up around the circumference of the nanotube.
The density of electronic states as a function of energy has been calculated for a variety of nanotubes. While conventional metals have a relatively smooth density of states, nanotubes are characterized by a number of singularities, where each peak corresponds to a single quantum subband. These singularities are important when interpreting experimental results, such as measurements obtained from scanning tunneling spectroscopy and resonant Raman spectra, the two techniques that have contributed the most to understanding the one-dimensionial properties of nanotubes.
A nanotube may be either metallic or semiconducting, however the chemical bonding between the carbon atoms is the same in both cases. This is due to the very special electronic structure of a two-dimensional graphite sheet, which is a semiconductor with a zero band gap. In this case, the top of the valence band has the same energy as the bottom of the conduction band, and this energy equals the Fermi energy for one special wavevector, the so-called K-point of the two-dimensional Brillouin zone (i.e. the corner point of the hexagonal unit cell in reciprocal space). A nanotube becomes metallic when one of the few allowed wavevectors in the circumferential direction passes through this K-point.
As the nanotube diameter increases, more wavevectors are allowed in the circumferential direction. Since the band gap in semiconducting nanotubes is inversely proportional to the tube diameter, the band gap approaches zero at large diameters, just as for a graphene sheet. At a nanotube diameter of about 3 nm, the band gap becomes comparable to thermal energies at room temperature.
Calculations show that concentric pairs of metal-semiconductor and semiconductor-metal nanotubes are stable. Nanometer-scale devices could therefore be based on two concentric nanotubes or the junction between nanotubes. For example, a metallic inner tube surrounded by a larger semiconducting (or insulating) nanotube would form a shielded cable at the nanometer scale. One might then envisage nanoscale electronic devices made completely from carbon that would combine the properties of metals and semiconductors, without the need for doping.
Since nanotubes are typically a few microns long, electrical contacts can be made by modern lithographic techniques. Single-wall carbon nanotubes thus provide a unique system for studying single-molecule transistor effects, in which an electrode close to the conducting nanotube is used to modulate the conductance. Another area of research is focused on the mechanical properties of carbon nanotubes. By analogy to graphite and carbon fibers, nanotubes are very strong and have high elastic moduli. Single-wall carbon nanotubes are also very strong and resist fracture under extension, just as the carbon fibers commonly used in aerospace applications. A nanotube can be elongated by several percent before it fractures. Unlike carbon fibers, however, single-wall nanotubes are remarkably flexible. They can be twisted, flattened and bent into small circles or around sharp bends without breaking, and severe distortions to the cross-section of nanotubes do not cause them to break.
Another advantage of nanotubes is their behavior under compression. Unlike carbon fibers, which fracture easily under compression, carbon nanotubes form kink-like ridges that can relax elastically when the stress is released. As a result, nanotubes not only have the desirable properties of carbon fibers, but are also much more flexible and can be compressed without fracture. The mechanical properties of carbon nanotubes would make them ideal for manipulating other nanoscale structures. Many of the applications now being considered involve multi-wall nanotubes, partly because they have been available for much longer, and partly because many of these applications do not explicitly depend on the one-dimensional quantum effects found mainly in single-wall nanotubes.
In the same way that carbon fibers are used in composites to strengthen a structure or to enhance the electrical conductivity of the main constituent, carbon nanotubes can be combined with a host polymer (or metal) to tailor their physical properties to specific applications. Since carbon nanotubes are so small, they can be used in polymer composites that are formed into specific shapes, or in a low-viscosity composite that is sprayed onto a surface as a conducting paint or coating.
Carbon nanotubes could also be used in displays or for the tips of electron probes. Other applications could result from the fact that carbon nanotubes can retain relatively high gas pressures within their hollow cores.
Several efforts have been made to grow nanotubes into patterned configurations (e.g., arrays), however the resulting arrays typically include several nanotubes that are irregularly spaced and have varying heights. Other efforts have shown that the growth of aligned nanotubes in several directions can be controlled in a single process. Though the functional feasibility to integrate nanostructures into micro-devices has been demonstrated by growing them into patterns, process couplings and scale mismatches between nano- and micro-fabrication processes limit the practical production of integrated devices. It has been stated that growing a uniform length nanotube-tip-array on 1 cm2 area would be equivalent to growing a perfectly healthy and uniform length grass lawn on 1,000 acres.
There have been few efforts regarding the handling and manufacturing of carbon nanotubes. One group has worked on the directed assembly of one-dimensional nanostructures into functional networks by fluidic assembly with a surface-patterning technique. Another research group developed a method of assembling single-walled CNTs into long ribbons and fibers. In this method the nanotubes are dispersed in surfactant solution and then the nanotubes are recondensed in the flow of a polymeric solution to form a nanotube fiber. Companies are selling commercial quantities of nanotubes in the form of soot, which cannot be handled effectively during the subsequent manufacturing processes. Other companies are working on flat panel displays using carbon nanotubes as emission tips. None of theses companies have reported commercially viable manufacturing solutions for the mass production of nanotubes.
As described above, there exists several potential applications using nanotubes, however widescale use of nanotubes will only become feasible if massive production of carbon nanotubes becomes a reality.

Method of making packets of nanostructures


Embodiments of the present invention disclose a method for obtaining a request of a station, an access point, and a station. The method includes sending, by an access point, a control frame to a station and receiving, by the access point, a frame requesting to send sent by each station according to the control frame. The method also includes performing, by the access point, resource scheduling on each station according to the received frame requesting to send.

A base station in a WLAN (wireless local area network) is also referred to as an AP (access point). Currently, in a WLAN system, an OFDM (orthogonal frequency division multiplexing) technology is generally used for transmission. However, to improve system efficiency, introduction of an uplink multi-users technology, such as an uplink OFDMA (orthogonal frequency division multiple access) technology and uplink multi-user MIMO (Multiple-Input Multiple-Output) technology, is under consideration into a standard. In the uplink multi-user technology, a problem that needs to be resolved is how the AP obtains an uplink data request of a STA (station).
Currently, there are multiple technologies for obtaining the uplink data request of the STA.
In a first technology, the uplink data request is obtained by means of random competition. Because random competition does not need a central station to control a network, random competition has a simple structure and flexible networking and is widely applied to a distributed network. However, when system load is very large and competition increases, conflict avoidance is relatively difficult, and an access requirement of a specific service cannot be met.
In a second technology, the uplink data request is obtained by means of polling. That is, the AP specifies multiple STAs to send uplink data requests on specified sub-channels by means of OFDMA. Because it is unknown which STAs have cached data, polling is blindly performed. As a result, system efficiency is reduced because the AP polls a large quantity of STAs that have no uplink data.

Method for obtaining request of station, access point, and station


A method, and the resulting structure, of growing a superconducting perovskite thin film of, for example YBa.sub.2 Cu.sub.3 O.sub.7-x. A buffer layer of, for example, the perovskite PrBa.sub.2 Cu.sub.3 O.sub.7-y, is grown on a crystalline (001) substrate under conditions which favor growth of a,b-axis oriented material. Then the YBa.sub.2 Cu.sub.3 O.sub.7-x layer is deposited on the buffer layer under changed growth conditions that favor growth of c-axis oriented material on the substrate, for example, the substrate temperature is raised by 110.degree. C. However, the buffer layer acts as a template that forces the growth of a,b-axis YBa.sub.2 Cu.sub.3 O.sub.7-x, which nonetheless shows a superconducting transition temperature near that of c-axis oriented films.

The discovery of high-temperature superconductors, commonly called high-T.sub.c superconductors, promises many technological applications. Although many types of low-T.sub.c superconducting devices are known, it has been difficult to fabricate high-T.sub.c equivalents. The highly anisotropic properties and complex perovskite crystal structure of most high-T.sub.c superconductors have contributed to this difficulty. This following discussion will use YBa.sub.2 Cu.sub.3 O.sub.7-x, hereinafter called YBCO, as an example since it appears to be the most understood as well as technologically usable high-T.sub.c superconductor.
The crystal structure of YBCO, illustrated in FIG. 1, is very closely related to the perovskite crystal structure, namely, an orthorhombic (or rectangular) structure with nearly equal a- and b-axes but a significantly longer c-axis. Unit cell parameters for YBCO, as well as those for SrTiO.sub.3, a popular substrate for growing YBCO thin films, are given in Table 1.
TABLE 1 ______________________________________ Lattice Parameters (nm) a b c ______________________________________ YBCO 0.382 0.338 1.168 PrBCO 0.387 0.393 1.171 SrTiO 0.391 0.391 0.391 ______________________________________
Arranged perpendicular to the c-axis are planes of CuO.sub.2, which are believed to be largely responsible for the superconductivity. The perovskite crystal structure is described by A. F. Wells in his book entitled "Structural Inorganic Chemistry," 4th ed., Clarendon Press, 1975 at pages 149-154.
The elongated and non-symmetric unit cell has caused difficulty in growing monocrystalline samples of YBCO. Nonetheless, many techniques have found increasing success. One of the most successful has been pulsed laser deposition in the growth of YBCO thin films. Details of the technique have been disclosed by Venkatesan et al. in U.S. patent application Ser. No. 07/331,795, filed Apr. 3, 1989 now U.S. Pat. No. 5,015,492 issued May 14, 1991 and by Hegde et al. in U.S. patent application Ser. No. 07/360,090, filed Jun. 1, 1989, now U.S. Pat. No. 5,087,605, issued Feb. 11, 1992. In this technique, an ultraviolet laser delivers short light pulses onto the surface of a composite target having a composition similar to that of the desired film. The plume of the non-equilibrium evaporation from the target falls on the substrate and forms the desired YBCO film. With careful control of the substrate temperature and ambient oxygen pressure, monocrystalline films can be grown on (001) oriented substrates of SrTiO.sub.3, MgO, and other materials. Such oriented substrates have surface unit cells closely matching the a- and b-axis lattice parameters of YBCO. The YBCO films grown by this method had a c-axis orientation perpendicular to the substrate. These films have demonstrated transition temperatures T.sub.c in the range of 90.degree. K.
Hedge et al. further used this c-axis epitaxial growth to form an epitaxial heterostructure of YBCO-PrBCO-YBCO. The middle layer was PrBa.sub.2 Cu.sub.3 O.sub.7-y, which is also a perovskite but is non-superconducting and behaves like a semiconductor. Its lattice parameters are also given in Table 1. Their intent was to form a Josephson weak link across the PrBCO, that is, between the YBCO layers across the PrBCO layer. Josephson devices produced using this method reproducibly demonstrated S-N-S (superconductor-normal-metal-superconductor) behavior in their current-voltage characteristics. Both DC and AC Josephson effects were observed. However, the performance of such c-axis grown heteroepitaxial devices is limited by the very short coherence length along this crystallographic direction. The coherence length, one of the key length parameters in superconductivity, is highly anisotropic in YBCO, as well as other known high-T.sub.c superconductors. The coherence length has a value }.sub.c .apprxeq.0.7 nm along the c-direction and a value .xi..sub.a,b .apprxeq.3.5 nm within the a-b plane YBCO. As a result, the coherence length in c-axis oriented YBCO-PrBCO-YBCO heterostructures is smaller than the smallest spacing that can be ideally achieved, specifically, a single unit-cell layer of PrBCO separating two layers of YBCO. It thus appears that even with ideal interfaces between YBCO and PrBCO, the performance of such c-axis oriented junctions will be limited.
On the other hand, the coherence length .xi..sub.a,b of .about.3.5 nm along the a- and b-directions of YBCO is nearly ten times the corresponding lattice parameters of PrBCO and YBCO. If heteroepitaxial structures could be grown with the c-axis lying within the film plane, they would provide a much wider latitude in the quality of the PrBCO barrier and of the YBCO-PrBCO interfaces. Even if the PrBCO barrier would be a few unit cells thick in the a,b-directions, there would still be sufficient overlap of the order parameters of the two YBCO electrodes.
In view of these potential advantages, many groups have attempted to grow a,b-axis oriented YBCO films. By a,b-axis oriented films is meant a film in which nearly all the material has its c-axis lying in the plane of the film. One approach to growing a,b-axis oriented perovskite films uses (110)-oriented substrates. A second approach simply lowers the substrate growth temperature by about 100.degree. C. At the lower temperatures, even on a (001) substrate, a large fraction of the YBCO forms in an a,b-axis orientation although there is some mixture with c-axis orientation.
Problems arise with both these approaches. In either case, the films lack homogeneity in their orientation along a particular direction. X-ray diffraction has shown that for both these processes, it is difficult to obtain films which are purely a-axis oriented or b-axis oriented. Other phases are almost always locked in. Furthermore, both processes produce a poorly crystalline structure. Regardless of orientation, the crystalline structure must be highly ordered to permit the epitaxial growth of overlayers, such as the PrBCO barrier or the YBCO counter-electrode. So far, there has been no convincing demonstration of epitaxial growth on top of a,b-axis oriented films previously grown on (110) or (001) substrates at the lower deposition temperatures. Finally, the temperature range in which a,b-axis oriented growth is induced on these substrates is usually below the optimal deposition temperature required to obtain the .about.90.degree. K. transition temperature achievable in c-axis oriented YBCO. Thus, efforts have failed in obtaining a,b-axis oriented films exhibiting good crystalline structure with a T.sub.c above the 60.degree.-70.degree. K. range.
It would be further preferred to achieve a,b-axis oriented growth on (001) substrates, which to date have yielded the best c-axis oriented films. Thereby, a commonly oriented substrate would provide greater flexibility in designing devices incorporating films and heterostructures of both orientations.
The problem of a short c-axis coherence length is present, as well, in the bismuth and thallium superconductors represented by the formula A.sub.2 B.sub.2 Ca.sub.2n-1 Cu.sub.n O.sub.y, where A is either Bi or Tl, B is either Ba or Sr, n=1, 2, or 3, and y is between 6 and 10. These perovskite materials are of technological interest because they manifest significantly higher values of T.sub.c ; however, their c-axis lattice parameters are also significantly longer.

Growth of a,b-axis oriented pervoskite thin films


The present invention is a transfer aid for assisting people with restricted mobility to rise from a seated position into a standing position. It is a lightweight, portable device having a portion for the user to grasp positioned directly in front of the user. Two supports are each located on either side of the portion to be grasped, and are each rotatable with respect to this portion. This adds flexibility to the device and permits it to be used in a plurality of situations. The transfer aid is easily transported by tilting it so that it rests upon wheels, or tilting it so that it rests upon plastic caps.

1. Field of the Invention
The present invention relates to a transfer aid designed for assisting a user in rising from a seated position. More particularly, the invention relates to a portable, lightweight transfer aid, capable of being used in conjunction with a standard walker or similar device.
2. Description of the Prior Art
People having a limited mobility often need assistance when rising from a seated position to a standing position. However, helping such a person carry out this activity is commonly too great a task for a single caregiver to undertake. The caregiver may not posses sufficient strength for effective assistance, and if the caretaker does posses such strength, the awkward act of lifting a person of limited mobility may result in injury to either the patient or caregiver, or both.
Devices for assisting persons to raise to a standing position, without the assistance of a caregiver, are known in the prior art. Common to these devices is a supporting mechanism for the user to grasp and exert force against in order to facilitate movement into a standing position. One type of supporting mechanism includes a plurality of support bars positioned in front of the user, where the bars can easily be grasped. This type of mechanism is seen in Joseph Schmerler U.S. Pat. No. 4,964,182, Oct. 23, 1990, which shows a transfer aid for elderly or infirm individuals. Included in this invention is a selectively swingable and extendable center frame having a plurality of assist bars for grasping by the user. This support frame is for positioning in front of the user and is securable in both a substantially vertical and horizontal position, depending upon the needs of the user.
A second type of supporting mechanism includes a pair of support bars for positioning on opposite sides of the user. Here, the user places one hand on each support bar so each arm is in a substantially vertical position. The user pushes downward on the support bar until he or she is in an upright position. Patents showing this type of supporting mechanism are Bernard J. Skibinski U.S. Pat. No. 4,922,560, May 8, 1990, Henry J. O'Keefe et al. U.S. Pat. No. 5,226,439, Jul. 13, 1993, and French Pat. No. 2 274 274 issued on Jan. 9, 1976.
The Skibinski patent discloses a portable assist having two handles attached to a rectangular platform. These handles are for the user to push upon when elevating himself or herself into a standing position. When the device is not being used, the handles may be rotated so as to rest on the platform.
The O'Keefe patent teaches a supporting device for use with standard chairs. The chair rests on a platform from which two vertically adjustable handles extend adjacent to either side of the user. The user pushes upon the handles when moving into an upright position, and the weight of the user and chair prevents the platform from slipping or tipping over. A similar device is shown in the French patent which also discloses two vertically adjustable handles. However, this invention does not include a platform to support the user as he or she rises to an upright position.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.


A solar cell has a P-type silicon substrate in which one main surface is a light-receiving surface and another main surface is a backside, a dielectric film on the backside, and an N-conductivity type layer in at least a part of the light-receiving surface of the P-type silicon substrate, wherein the P-type silicon substrate is a silicon substrate doped with gallium, and the backside of the P-type silicon substrate contains a diffused group III element. This provides a solar cell with excellent conversion efficiency provided with a gallium-doped substrate, and a method for manufacturing the same.

Semiconductor substrates for solar cells are usually manufactured by a Czochralski method (CZ method), which can produce a single crystal with a large-diameter at relatively low cost. For example, P-type semiconductor substrates can be obtained by drawing a silicon single crystal doped with boron by a CZ method, and slicing this single crystal. Thus obtained silicon substrates doped with boron, being irradiated with strong sunlight, cause decrease in the lifetime under the influence of boron and oxygen in the substrate. As a result, the light induced degradation comes to being.
In order to solve such light induced degradation issue, Patent Literature 1 proposes the use of gallium instead of boron as P-type dopant.
As a backside structure of solar cells, a structure having a Back Surface Field (BSF) region can be illustrated. The BSF region can be applied to the almost whole surface of the backside by printing an aluminum, paste to the almost, whole surface of the backside of a substrate and firing thereof.
Other structures include a structure which has local contacts between the substrate and a back surface electrode and is protected by a dielectric film on the most of the back surface, which acts as a passivation layer, in order to further improve the efficiency. These solar cell structures are referred to as a Passivated Emitter and Rear Contact Solar Cell (PERC) structure and a Passivated Emitter and Rear Locally Diffused Solar Cell (PERL) structure.
The cross section of the solar cell having a previous PERL structure is schematically shown in FIG. 6. As shown in FIG. 6, the solar cell 110 is provided with the N-conductivity type layer (emitter layer) 112 on the side of the light-receiving surface of the P-type silicon substrate 111, and the light-receiving surface electrode 116 on this N-conductivity type layer 112. In many cases, the solar cells each nave the anti-reflection film 114 on the light-receiving surface. The solar cell is also provided with the dielectric film 115, which acts as a passivation film or a protective film, on the back surface; the back surface electrode 117 on the back surface; and the BSF layer 113 at the contact area where the back surface electrode 117 is in contact with the P-type silicon substrate 111.

Solar cell and method for manufacturing the same


A computer implemented method and system for capturing events of interest by performing a spatio-temporal analysis of a video are provided. A continuous video stream containing a series of image frames is acquired over time. Each of the image frames is represented by horizontal spatial coordinates and vertical spatial coordinates of a two dimensional plane. A temporal dimension is assigned across the image frames of the video stream. A spatio-temporal analysis image is constructed based on a user-defined line of analysis on each of one or more of the image frames. The spatio-temporal analysis image is constructed by concatenating a series of temporally-successive linear pixel arrays along the temporal dimension. Each of the linear pixel arrays comprises an array of pixels along the line of analysis defined on each of one or more of the image frames. The constructed spatio-temporal analysis image is segmented for capturing the events of interest.

Video content analysis (VCA) refers to processing of video for determining events of interest and activity in a video, such as, a count of people or vehicles passing through a zone, the direction and speed of their movement, breach of boundary, speeding vehicles, etc. using computer vision techniques. VCA finds numerous applications in video surveillance, customer behavior in super markets, vehicular traffic analysis, and other areas. VCA is becoming a necessity given the extent of breach of security, requirement for surveillance, and threats to or potential compromise of human life and property in cities, defense establishments and at industrial and commercial premises.
Existing VCA algorithms process an entire image or a patch of the image using pure spatial image processing of the video. Hence, these algorithms are inherently suboptimal with respect to their computational efficiency and memory utilization. For example, processing visual graphics array (VGA) image frames of 640×480 pixels each in pure spatial domain requires segmentation of the entire 307200 pixels of each image frame, which is highly memory intensive.
Hence, there is a long felt but unresolved need for a computer implemented method and system for capturing events of interest by performing spatio-temporal analysis of a video using user-defined lines of analysis.

Capturing events of interest by spatio-temporal video analysis


The invention is a liquid composition, and method of use, for a pre-rice-seed-germination herbicide for dry or drill seeded rice. The composition includes pendimethalin and pinolene. It is applied in a spray volume of about 18.9-75.7 L per ha (5-20 gal per acre) of rice. After applying the herbicide, the field is flush irrigated with water. The composition is not phytotoxic and significantly reduces the amount of weed germination.

1. Field of the Invention
The invention relates generally to crop herbicides, and, in particular, to an herbicide that contains pendimethalin and pinolene for dry and drill seeded rice.
2. Description of the Related Art
Pendimethalin has been used as a rice herbicide for dry and drill seeded rice throughout the world for many years. The use of pendimethalin, however, has been strictly limited to use after the rice seed has germinated (i.e., after the first irrigation or rainfall). In fact, current and past pendimethalin registrations have expressly prohibited the use of pendimethalin before rice germination. The reason for this limitation is that pendimethalin is a root inhibitor and is therefore toxic to germinating rice seed. As long as pendimethalin is used after the rice seed has germinated, it is not toxic to the rice because it is not in contact with the seed.
The disadvantage of pendimethalin is that it must be used after the rice seed has germinated, which is also after a significant amount of weeds have germinated and begun to grow.
Thus, there is a need for a pre-flush, pre-rice-seed-germination herbicide.

Herbicide composition and method for dry and drill seeded rice


The present invention provides a heat-screening glass provided with a protective film having improved wear resistance and chemical resistance in comparison with a protective film of silicon dioxide. A heat-screening glass according to the present invention is composed of a transparent sheet glass and a heat-screening film coated thereon and a protective film made of silicon oxynitride as an outermost layer. The protective film is made of silicon oxynitride represented by the formula SiO.sub.x N.sub.y (where x ranges from 0.65 to 1.25 and y ranges from 0.05 to 0.67) .

Field of the Invention
The present invention relates to a heat-screening glass which has a chemical- and wear-resistant protective film as the outermost layer on a transparent sheet glass.
Description of the Prior Art
It is a recent practice to use a heat-screening glass coated with a heat-screening film in order to reduce the influx of solar energy through building and automotive windows. A known example of such glass is the one which utilizes the property that heat rays are reflected by a film of metal (such as Cu, Al, and Ag) or a film of metal nitride (such as titanium nitride and zirconium nitride). The other known example is the one which has, for reflection of heat rays, alternately formed films of high-refracting and low-refracting materials. If they are to be used alone, they should have good mechanical, wear, and chemical resistance, among others, scratch resistance.
To meet this requirement, there was proposed a heat-screening glass which has a thick oxide film, for example, an SiO.sub.2 film thicker than 1 .mu.m, as the outermost layer, formed on the coating layer. (See Japanese Patent Laid-open No. 206333/1988.) There was also proposed a protective film of ZrB.sub.x O.sub.y, SnO.sub.2, or SiO.sub.2. (See Japanese Patent Laid-open No. 314163/1989.)
However, the protective film of SiO.sub.2 thicker than 1 .mu.m has a disadvantage of taking a long time for its coating, which leads to low productivity and high production cost. The protective film of SnO.sub.2 is poor in chemical resistance, and the protective film of ZrB.sub.x O.sub.y lacks reproducibility.


A laundry machine and a method of controlling the laundry machine are disclosed. The laundry machine includes a steam generator (300) which generates steam to supply the steam into a drum (130), a water supply line (320) which supplies water into the steam generator (300), a filter (360) installed in the water supply line (320) to filter water, a regenerating unit (382) which regenerates the filter (360), and a controller which controls operations of the steam generator (300) and the regenerating unit (382).

Generally, a washing machine performs washing rinsing and water-extracting operations by rotating a rotary drum and a pulsator by a driving force of a motor. Washing water and the laundry are loaded and agitated in the rotary drum, whereby the laundry is washed by friction of the washing water, the laundry and the rotary drum.
Washing machines are classified into a pulsator-type washing machine, an agitator-type washing machine, a drum-type washing machine and the like according to the washing manner.
In general, the drum-type washing machine performs the washing operation using a frictional force between the laundry and a washing drum rotating by a driving force of a driving unit in a state where a detergent, washing water and the laundry are loaded in the drum. The drum-type washing machine prevents the laundry from being damaged and tangled, and provides a washing effect of beating and rubbing.
Meanwhile, a laundry dryer is a machine which automatically dries washed, wet articles to be dried (for example, clothes).
The washing machines include a washing machine with a steam generator. For example, FIGS. 1 and 2 show a conventional washing machine with a steam generator.
First, the conventional washing machine is a drum-type washing machine which includes a main body 110, a tub 120, a drum 130, a driving motor 171 and a steam generator 200.
The main body 110 forms an external appearance of the drum-type washing machine. The tub 120 is disposed in the main body 110 to be supported therein.
The drum 130 is rotatably installed in the tub 120 such that an opened portion of the drum 130 faces a loading port 111 of the main body 110.
A door 140 is installed on the loading port 111 of the main body 110 to open/close the loading port 111. A rim portion 150 for sealing between the door 140 and the loading port 111 is mounted on an inner peripheral surface of the loading port 111.
Further, the driving motor 171 is a motor driven to rotate the drum 130. The driving motor 171 is directly connected to the drum 130 to rotate the drum 130.
Further, the steam generator 200 heats water into steam and provides the steam into the drum 130.
A heater 210 for heating water into steam is disposed in the steam generator 200. The steam generated from the steam generator 200 flows into a steam supply line 220 having a valve 221 and is supplied into the drum 130 through an injection nozzle 230.
The steam generator heats water to generate the steam. In this case, deposits are generated and accumulated in the steam generator. Particularly, a large amount of deposits are generated in water with a high hardness. The problem of generation of deposits is severe in Europe where the quality of water is low.
When lots of calcium ions or magnesium ions are included in water, the amount of deposits becomes larger.
The generated deposits cause contamination in the steam generator. Further, the deposits are adhered to the surface of a heater of the steam generator, thereby reducing its efficiency.

Laundry machine and controlling method thereof


An evaporation panel can include a first evaporation shelf including a first upper surface and a first lower surface, a second evaporation shelf positioned beneath the first evaporation shelf and having a second upper surface, and a support column disposed between the first evaporation shelf and the second evaporation shelf. In this example, the support column can include an evaporation fin.

There are several techniques used to separate water from various contaminants, such as hydrocarbons, salts, debris, dirt/clay, coal, hazardous material, or the like. Sources of industrial wastewater come from various industries generally, such as from facilities including chemical plants, fossil-fuel power stations, food production facilities, iron and steel plants, mines and quarries, nuclear plants, and others. Thus, evaporation from evaporation ponds has been used to separate various types of contaminants from water. For example, salt evaporation can be used to produce salt from seawater, or can be used to dispose of brine from desalination plants. Mining operations can use evaporation to separate ore or other material from water. The oil and gas industry can use evaporation separate various hydrocarbons from water. Evaporation can also be used to separate water from various types of hazardous or non-hazardous waste, reducing its weight and volume to make it more easily transportable and stored.
As many industries produce some wastewater, there is a trend towards minimizing wastewater production and/or recycling wastewater where possible. However, typical evaporation ponds can be large, taking up a significant amount of real estate (which may not be available in some instances), and evaporation ponds can take months to adequately evaporate/separate the waste material from the water though evaporation.


A closure for an open headed medical implant, such as a bone screw. The closure having a cylindrical body having an axis of rotation and also having a radially outer surface with a thread or other guide and advancement structure thereon. The body having a plurality of apertures that open onto a top surface of the body and that are parallel to but spaced from the axis of rotation. The closure also has a break-off head centrally attached by a neck to the top surface of the body.

The present invention is directed to an open headed medical implant and, in particular, to a closure for closing the head of an open headed bone screw, hook or the like.
Bone screws are used especially in spinal surgery to support and position various implants needed to repair a spine that has suffered injury, illness or genetic defect. Bone screws of this type are screwed into the vertebrae of the spine and have a head that projects outside the bone which receives other implants, such as rods, that extend along the spine. Bone screws are of two general types which are either open headed or closed headed. Hooks and certain other implants also sometimes have open heads. The present application is directed to open headed bone screws and related implants such as hooks and the like that have such an open head to receive another implant.
In open headed bone screws and related implants, the head includes two upright arms that form a channel therebetween. The channel is sized to receive a rod or the like and is open to make it easier to place the rod in the head. The rod must then be tightly held or locked in the head to prevent relative movement between implants after the surgery. To hold the rod in the head, plugs have been used that are screwed into threads on the interior surfaces of the arms.
The present invention is directed especially to improvements in such plugs or closures that make them easier to insert in the head, that better ensure that the plug effectively secures the rod so that the rod does not later slip, that allow the plugs to be easily removed should the overall implant system require rearrangement and which provide a comparatively low profile, so as reduce trauma and irritation to the surrounding tissues of the patient.


A brake actuator has a body containing a pair of brake-applying members which may be actuated hydraulically to separate the friction elements of a brake into engagement with a rotatable braking surface. The members are interconnected by a mechanism in the form of a shaft of which respective end portions are provided with reversible threaded portions of opposite hand which engage corresponding threads within the members, the shaft being constrained against axial movement between bearings. Any excess movement of one of the members relative to the other is transmitted to that other member such as to cause an opposite and proportional force on the other member to substantially equalize the wear rates on the friction elements.

This invention relates to a brake actuator intended for use primarily, although not exclusively, with an internal shoe drum brake of the leading/trailing type, usually known as a simplex brake.
One characteristic of drum brakes is that they operate with a degree of self-energization or servo derived from the rotating brake drum and this tends to increase the braking force on the leading shoe and reduce the braking force on the trailing shoe, as is well understood. A result of this is that the friction material of the leading shoe wears away at a faster rate than that of the trailing shoe with consequent inconvenience to users in terms of servicing requirements.
A proposal to deal with the unequal wear problem is illustrated in British Patent No. 456238. This provides the trailing shoe with an automatic adjuster device coupled by a flexible drive element to the leading shoe so that adjustment is applied in equal amounts to both shoes. Although this partially corrects the unequal wear, the aforesaid characteristic of unequal braking forces at the respective shoes, which gives rise to the unequal wear, remains unchanged.
Another partial solution to the problem has been attempted by using friction linings of different thickness on the leading and trailing shoes, but this again deals with the effect of the problem rather than its fundamental cause and results in the inconvenience of "handed" shoes.
In a further prior proposal, a hydraulic actuator is provided with opposed pistons having different working areas, the pistons being arranged so that the larger actuating force is applied to the trailing shoe. Whilst this can in theory balance the forces applied respectively to the leading and trailing shoes, it is not entirely satisfactory because the geometry of the brake varies during use and it is difficult in practice to match the forces to the theoretical ideal.


A tooth-fixing member of a shape memory alloy including two pairs of fixing fingers formed on both sides of a band base for engaging teeth, the pair of fixing fingers being processed to open in parent phase and close in martensite phase. Tooth fixing procedure includes the steps of: forming a cavity in each of plural target teeth; inserting each pair of fixing fingers of the tooth-fixing member in martensite phase into the cavity; and heating the tooth-fixing member to the parent phase to open the fixing fingers so as to fix the teeth together. The tooth-fixing member applicable to various dental treatments, which include: fixation of teeth which are loose due to periodontal diseases like pyorrhea alveolaris; fixation of teeth to ensure a space for a tooth to erupt; fixation of a tooth which is extruding abnormally; fixation of a transplanted tooth; and correction of slanting teeth.

1. Field of the Invention
The present invention relates to a tooth-fixing member used for fixing teeth which are loose due to periodontal diseases like pyorrhea alveolaris, and also to a method of fixing teeth with the fixing member.
2. Description of Related Art
As the periodontal tissue is successively damaged from the circumference of gingiva and alveolar bone gradually recedes in the course of periodontitis, teeth in the lesion of periodontitis become loose; this is a typical symptom of pyorrhea alveolaris. There are mainly two treatment procedures for teeth in pyorrhea alveolaris: extraction of a tooth which is extremely loose and of no use; and fixation of a tooth, which is loose but has some chance to survive, to an adjacent tooth with no or only slight looseness.
Fixation of a loose tooth to an adjacent tooth is generally implemented with metal wire. In concrete terms, target teeth, that is, a loose tooth, and its adjacent tooth, are tied with metal wire having sufficient elasticity and are then exposed to loading due to bending or tension of the metal wire so as to be securely fixed.
The method mentioned above, however, has some drawbacks; fastening target teeth with metal wire is both labor and time consuming; loading applied to the teeth gives a patient persistent pain and uncomfortable feeling; and the metal wire is undesirably seen whenever the patient opens the mouth.
Some methods of correcting the dental arch with shape memory alloy have been proposed; for example, Japanese Patent Laid-Open No. 49-50790 and No. 58-44047. An example of such method is briefly explained. An orthodontic member of shape memory alloy wire is processed through heat treatment so as to have a desirable shape to give the anatomically favorable dental arch in parent phase. The processed orthodontic member is fit on the dental arch of a patient at relatively low temperatures and is then heated to regain the original shape, thereby correcting the dental arch by taking advantage of its elastic force. While there are several disclosures regarding such orthodontic members of shape memory alloy, application of shape alloy metal to a tooth-fixing member has not yet been proposed.

Tooth fixing member and method of fixing teeth with the member


A method of forming a semiconductor device package includes the following steps. A redistribution structure is formed on a carrier. A plurality of second semiconductor devices are disposed on the redistribution structure. At least one warpage adjusting component is disposed on at least one of the second semiconductor devices. A first semiconductor device is disposed on the redistribution structure. An encapsulating material is formed on the redistribution structure to encapsulate the first semiconductor device, the second semiconductor devices and the warpage adjusting component. The carrier is removed to reveal a bottom surface of the redistribution structure. A plurality of electrical terminals are formed on the bottom surface of the redistribution structure.

In the packaging of integrated circuits, device dies, which may be stacked vertically as well as horizontally, are packaged onto redistribution structures. The device dies may be bonded onto one side of a redistribution structure using flip chip bonding, and a reflow is performed to melt the solder balls that interconnect the dies and the redistribution structure. Then, a molding compound is applied on the package, with the molding compound covering the device die and the solder balls.
However, there is significant mismatch between the Coefficients of Thermal Expansion (CTEs) of the materials in the packages. For example, the redistribution structures and the molding compound have CTEs that are much higher than that of the device dies. Accordingly, in the resulting package, there is a significant warpage. The warpage in the package substrates may cause irregular joints and/or bump cracks. The warpage may be further worsened by the asymmetrical arrangement of device dies over the redistribution structures. As a result, the yield of the packaging process is adversely affected.

Method of forming semicondcutor device package

Taiwan Semiconductor Manufacturing Co., Ltd.


A method for displaying a shadow of a 3D virtual object, includes steps of: (a) acquiring information on a viewpoint of a user looking at a 3D virtual object displayed in a specific location in 3D space by a wall display device; (b) determining a location and a shape of a shadow of the 3D virtual object to be displayed by referring to information on the viewpoint of the user and the information on a shape of the 3D virtual object; and (c) allowing the shadow of the 3D virtual object to be displayed by at least one of the wall display device and a floor display device by referring to the determined location and the determined shape of the shadow of the 3D virtual object. Accordingly, the user is allowed to feel the accurate sense of depth or distance regarding the 3D virtual object.

Recently, three dimensional image display devices have been popularized and accordingly, numerous attempts have been made at watching virtual objects through such devices. In particular, a technology that allows a user to directly manipulate and touch a virtual object outputted (i.e., displayed) through a 3D image display device is more requested. To implement such a technology, the user must recognize at which location in actual place the virtual object is placed.
Because a sense of depth, i.e., a feeling of a user regarding to what degree the virtual object is projected to actual space or move into the display surface based on a display surface of the 3D image display device, or a sense of distance that the user feels about the virtual object displayed through the 3D image display device depends on a cognitive ability of an individual user, there is a limit that each user cannot but feel the sense of depth or distance differently.
In addition, it has a limit that all users are provided with the same sense of depth or distance only when the user himself or herself must conduct manual pre-calibrated work because 3D images are created by using optical illusion due to the difference between the views of left and right eyes of the user.

Method, system and computer-readable recording medium for displaying shadow of 3D virtual object

Center Of Human-Centered Interaction For Coexistence