A zero-crossing circuit and method, in which the sign of inputs to a comparator is reversed after each zero crossing of the input signal. This means that delay introduced by the comparator does not affect the duty cycle of the output signal, so precision synchronization remains possible.

Zero-crossing detectors are generally composed of a single comparator or of a plurality of cascaded comparators, the output of which changes state every time the input signal crosses the zero level. These circuits are widely employed in digital and in analog-digital systems. The figure-of-merit parameters of these circuits are typically: speed, gain, and the equivalent input offset.
Commonly, in communication systems that employ a peak detection technique, the first derivative of an input signal is fed to a zero-crossing detector. In this way, a digital signal may be obtained that is exactly synchronized with the zero-crossings of the signal representing the first derivative of the input signal and therefore with the positive and negative peaks of the input signal.
In this as in other applications, a net offset of the zero-crossing detector circuit produces an error of synchronization that is commonly referred to as "Pulse Pairing". This phenomenon is graphically depicted in FIG. 1. As may be observed from FIG. 1, for a sinusoidal input signal of frequency f and amplitude Vp, an equivalent input offset .DELTA.V produces a "Pulse Pairing" delay whose value .tau. is given by the following expression: ##EQU1##
It is evident that error, in terms of the "duty cycle" of the output signal, is introduced by the Pulse Pairing phenomenon. In the depicted example, the "duty cycle" of the output signal contains an error that is equivalent to 2.tau..
As mentioned above, a zero-crossing detector circuit may be constituted by a single comparator, for example the one depicted in FIG. 3. More often though, because of amplification requirements, the circuit is composed of a plurality of comparators connected in cascade. For example the circuit may be constituted by two comparators G1 and G2 in cascade, as schematically shown in FIG. 2. Of course, the two comparator stages G1 and G2 may have an identical circuit, as the one shown in FIG. 3.
For a comparator circuit as shown in FIG. 3, the standard deviation of the equivalent input offset is given by: ##EQU2## where: V.sub.trj,k is the standard deviation of the offset relative to the differential pairs T1-T2 and T3-T4;
.DELTA.R/3R is the standard deviation of the percentage error relative to the load resistances R; PA1 V.sub.t is the so-called thermal voltage that is equal to about 26 mV at room temperature.
By assuming the two stages G1 and G2 of the circuit of FIG. 2 are identical, they will have the same small signal gain Gj given by: ##EQU3## The equivalent input offset of the circuit will be given by the following expression: ##EQU4##
Notably, the offset of a differential pair of transistors depends primarily on the emitter area of the transistors and the biasing current. For example, in the case of an advanced CMOS process for high frequency, the dependence of the offset on the emitter area may be quantitatively derived from the curves of FIG. 4, which show the value of the standard deviation of the offset (.mu.V) as a function of the current density (.mu.A/.mu.m.sup.2) and respectively for a minimum emitter area (25 .mu.m.sup.2), for an emitter area equal to ten times (10.times.) the minimum area (250 .mu.m.sup.2) and for an emitter area equivalent to one hundred times (100.times.) the minimum emitter area (2500 .mu.m.sup.2). The same curves are shown in semilogarithmic form in FIG. 5, wherein the reference level 0 dB represents the offset of a minimum emitter area (25 .mu.m.sup.2) at low current density (which for the case shown is equivalent to 212 .mu.V).
On the basis of the above sample data, by supposing: EQU Area.sub.tr =25 .mu.m.sup.2 I.sub.1 =100 .mu.A I.sub.2 =50 .mu.A EQU R=4080 .OMEGA. .DELTA.R/R=.+-.0.5% EQU V.sub.tr1,2 =V.sub.tr3,4 =424 .mu.V
a standard deviation of the equivalent input offset may be calculated to be equal to: EQU .sigma..sub.offset =601 .mu.V giving a V.sub.off =3 .sigma..sub.offset =1,8 mV
By employing the above formula for calculating the Pulse Pairing with Vp=100 mV, f=9 MHz, one obtains: EQU Pulse Pairing=637 psec.
In many applications, for example in read/write channels of a mass memory system, such as a hard disk system, the working frequency of the circuit is often lower than 9 MHz, for example 4 MHz, and the input signal may have a remarkable amplitude, for example on the order of 500 mVp. In a relatively relaxed situation such as this, a circuit such as the one analyzed above would produce a Pulse Pairing of about 286 psec. which could be acceptable, depending on the application. By contrast, in case of high performance applications and of read/write channel specifications for advanced systems, more restrictive conditions may be imposed on Pulse Pairing besides those mentioned above. For example, the requirements of read/write channel specifications of new-generation systems may indicate operating conditions of Vp=100 mV, f.sub.min =9 MHz and a maximum Pulse Pairing limit of 250 psec.
These requirements would impose a maximum equivalent input offset value of 700 .mu.V.
By assuming again: EQU I.sub.1 =100 .mu.A I.sub.2 =50 .mu.A EQU R=4080 .OMEGA. .DELTA.R/R=.+-.0.5%
and a 1% precision of the current mirrors that feed the two emitter followers of the comparator circuit of FIG. 3, and by neglecting the contribution of a second comparator stage, the standard deviation of the offset of the differential pairs, suitable to satisfy the above mentioned specs, becomes: EQU V.sub.tr1,2 =V.sub.tr3,4 =150 .mu.V
As a consequence, the emitter area required for ensuring such an input offset limit at a bias current of 50 .mu.A is given by: EQU Area.sub.tr =100 .mu.m.sup.2
By assuming that the zero-crossing detector circuit is integrated in a mixed technology device, characterized by the formation of bipolar and CMOS structures in the same semiconducting substrate, for which the improvement of application techniques has permitted the decrease of the minimum definition sizes from 2 .mu.m for CMOS gates and 25 .mu.m.sup.2 for NPN emitters to 0.7 .mu.m and 1 .mu.m.sup.2, respectively, an emitter area one hundred times greater than the minimum area would have to be realized.
Therefore, while in a mature fabrication process the required increment of the emitter area would correspond to about four times the minimum emitter area, in an advanced fabrication process, the realization of the eight NPNs (four for each comparator stage of FIG. 3) so as to ensure the level of offset established by the specs would be equivalent to eight hundred minimum emitter areas.
It is evident that such a method of containing the offset within the limits dictated by the system specs, in the case of integrated circuits made with advanced fabrication processes would be very burdensome in terms of area requirements.
Alternative ways for reducing the offset have been proposed, for example by realizing parallel differential pairs, one of which would be variable so as to be periodically trimmable through a specific routine for controlling the offset. However, these systems are themselves complex and expensive to implement.

Offset reduction in a zero-detect circuit


In one example, an apparatus of an e-NodeB (eNB) capable to establish a communication connection with a user equipment (UE) in a communication network, the eNB comprising processing circuitry to transmit a downlink (DL) beamforming training reference signal (BF-TRS) to a user equipment (UE) using transmit beamforming weights that are the same. Other examples are also disclosed and claimed.

Wireless communication systems which utilize mid-band (e.g., 6 GHz to 30 GHz) and high-band (e.g., over 30 GHz) frequency ranges may utilize beamforming techniques to compensate for relatively large path loss incurred during transmission between an eNodeB (eNB) and one or more user equipment (UE). Accordingly, techniques for transmit beamforming may find utility, e.g., in electronic communication systems for electronic devices.
It will be appreciated that for simplicity and/or clarity of illustration, elements illustrated in the figures have not necessarily been drawn to scale. For example, the dimensions of some of the elements may be exaggerated relative to other elements for clarity. Further, if considered appropriate, reference numerals have been repeated among the figures to indicate corresponding and/or analogous elements.

Beamforming training reference signal design


The present invention relates to a method of enhancing the efficacy of one or more agents in a subject by administering the agent or agents and a context-dependent functional entity to the subject, wherein a context-dependent functional entity includes a substructure with thrombogenic potential operably linked to a selective recognition domain, and interacts with a function-forming context expressed by a cell or tissue in the subject. The invention also relates to a method of treating a pathologic condition in a subject by administering to the subject a therapeutic agent and a context-dependent functional entity. The invention further relates to a pharmaceutical composition, which contains an agent and a context-dependent functional entity in a pharmaceutically acceptable form. The invention further provides a peptide having the amino acid sequence Pro-Arg-Lys-Leu-Tyr-Asp (SEQ ID NO: 1).

1. Field of the Invention
The present invention relates generally to medical procedures and more specifically to methods of using a context-dependent functional entity to enhance the efficacy of one or more agents in a subject.
2. Background Information
Although cancer remains a leading cause of morbidity and mortality in the world, it appears that more efficacious drugs and treatment protocols are providing increased hope that many, if not all, cancers eventually will be treatable. In some cases, the advances in treatment are due to improved surgical techniques or improved methods of radiation therapy. Advances also have been due to the identification of one or more drugs that are particularly effective for treating cancer. Taxol(copyright), for example, which is a natural product prepared from the Pacific yew tree, can prolong survival of patients with ovarian cancer, which has a very low survival rate. Platinol(copyright), which is a cis-platinum product, is effective in treating metastatic testicular cancer, and also is indicated in bladder cancer that has progressed to a stage that no longer can be treated by surgery.
Further advances in cancer therapy have been made by combining therapies, including surgery and radiation therapy, surgery and drug therapy, radiation therapy and drug therapy, and combined drug therapies. Where feasible, surgery often is used initially to remove the bulk of a tumor, then radiation therapy or chemotherapy is used to kill cells that may be outside of the region of surgery, including metastatic lesions. Treatment of a cancer patient with a drug such as hydroxyurea, which appears to inhibit DNA synthesis in cells, sensitizes the inhibited cells, including cancer cells, to the effects of radiation and, therefore, often is combined with radiation therapy.
Where surgery or radiation therapy cannot provide a significant treatment modality due, for example, to the location or extent of a cancer, combined drug modalities often are the treatment of choice. Generally, drugs are combined based on their having different mechanisms of action. Thus, an antimetabolite, which kills cancer cells by inhibiting DNA synthesis, can be combined with an agent that kills cells by inhibiting cell division. Such combined modalities generally have an additive effect due to each of the agents killing a population of cells sensitive to the drug.
Occasionally, combined modalities can result in a greater than additive effect. For example, treatment with Herceptin(copyright), which is a monoclonal antibody that recognizes a particular cell surface receptor expressed on breast cancer cells, in combination with two chemotherapeutic agents, kills a greater number of cells than would be expected due to simple additive effects. Where combined modality treatment results in a greater than additive effect of cancer cell killing, the dose of each drug often can be reduced. The ability to reduce the doses of chemotherapeutic agents, while still maintaining a therapeutic effect against a cancer, provides a significant therapeutic benefit, since it is the toxic side effects of cancer chemotherapeutic agents to normal cells that often limits the dose of drug that can be administered to a patient and, therefore, limits the treatment. By decreasing the amounts of drugs that need to be administered to a patient to effectively treat a cancer, side effects such as bone marrow depletion, loss of appetite, and hair loss are less severe, thereby improving the patient""s quality of life.
Agents such as Herceptin(copyright), which, when combined with other agents, enhance the efficacy of a second drug by producing a greater effect than otherwise would be expected, would be particularly useful for treating diseases such as cancer. Unfortunately, few agents that generally produce such an effect have been identified. Thus, a need exists to identify agents that can be administered, for example, in combination with one or more therapeutic drugs and increase the effectiveness of the drugs. The present invention satisfies this need and provides additional advantages.
The present invention relates to a method of enhancing the efficacy of one or more agents in a subject by administering to the subject the agent or agents and a context-dependent functional entity (xe2x80x9cCDFExe2x80x9d). A CDFE is a chimeric molecule that is composed of modular components and that acts as an integrated unit, which exhibits a functional activity in a position and orientation dependent manner. A CDFE can interact with a function-forming context expressed on a cell or in a tissue in the subject and, as disclosed herein, enhance the efficacy of an agent administered with the CDFE in a subject.
The modular components of a CDFE include a substructure with thrombogenic potential operably linked to a selective recognition domain. The substructure with thrombogenic potential can be a coagulation factor, for example, a vertebrate tissue factor (TF) or a modified form of TF such as a peptide portion of TF having thrombogenic potential. The selective recognition domain can be a kringle domain, for example, a plasminogen kringle 5 domain, or a peptide portion thereof such as the amino acid sequence Pro-Arg-Lys-Leu-Tyr-Asp (SEQ ID NO: 1); or can have, for example, the amino acid sequence as set forth in SEQ ID NO: 2. The substructure with thrombogenic potential is operably linked to the selective recognition domain, or other modular component, either directly or through a spacer element.
A CDFE can interact with a function-forming context expressed on the surface of a cell or in a tissue in the subject, for example, in vascular tissue such as tumor associated vascular tissue, thereby enhancing the efficacy of one or more agents at the site of the cell or tissue. The agent can be, for example, a diagnostic agent, a nutritional molecule, a toxin, a radiation sensitizer, or a therapeutic agent such as a cancer chemotherapeutic agent or other agent or combination of agents, and can be in an encapsulating matrix such as a liposome, which can be a modified liposome. For example, a method of the invention can include administering a cancer chemotherapeutic agent such as doxorubicin, which may or may not be encapsulated in a modified liposome, and a CDFE, either in combination or sequentially in any order; by any of various routes, including, for example, parenterally, intravenously or orally; systemically or at the site of a tissue in which it is desired to enhance the efficacy of the agent; and the timing of administration of the CDFE and the agent can be varied.
The invention also relates to methods of treating a pathologic condition in a subject by administering to the subject a therapeutic agent and a CDFE, which contains a substructure with thrombogenic potential operably linked to a selective recognition domain, whereby interaction of the CDFE with a function-forming context expressed on a cell or in a tissue in the subject enhances the efficacy of the therapeutic agent in the subject, thereby treating the pathologic condition. The pathologic condition can be a cell proliferative disorder, for example, a neoplasm, which can be benign or malignant. The substructure with thrombogenic potential can be a coagulation factor or a portion thereof, for example, a vertebrate TF or a modified form thereof, and the selective recognition domain can be a kringle domain or a portion thereof. Where the pathologic condition to be treated is a malignant neoplastic disease, the therapeutic agent is a cancer chemotherapeutic agent or a combination of chemotherapeutic agents, for example, an antimetabolite, an alkylating agent, an antitumor antibiotic, a cytokine, a hormone, a hormone antagonist, a nitroso compound, a plant alkaloid, a platinum compound, or the like, and can be encapsulated in a liposome, which can be a modified liposome. Where a subject is to be treated by radiation therapy, a therapeutic agent can be a radiation sensitizing agent.
The invention further relates to pharmaceutical compositions, which contain a CDFE and one or more agents in a pharmaceutically acceptable form, wherein the CDFE comprises a substructure with thrombogenic potential and a selective recognition domain. For example, the CDFE can include a modified form of tissue factor and kringle domain, which can be operably linked through a peptide spacer element. The agent can be a diagnostic agent, a nutritional molecule, a toxin, a radiation sensitizer, a therapeutic agent, or the like, or combinations thereof
The invention also provides a peptide having the amino acid sequence Pro-Arg-Lys-Leu-Tyr-Asp (SEQ ID NO: 1). Such a peptide is useful, for example, as a selective recognition domain, which can facilitate an interaction of a CDFE with a function-forming context. Polypeptide sequences containing SEQ ID NO: 1 are encompassed within the claimed invention, provided the polypeptide sequence is not plasminogen or a peptide portion of plasminogen containing SEQ ID NO: 1. In particular, chimeric molecules, including, for example, fusion polypeptides, comprising SEQ ID NO: 1 are encompassed within the invention.

Use of a context-dependent functional entity to enhance the efficacy of an agent


Metal-N-based or metalloid-N-based materials absorb a substantial amount hydrogen and are useful as hydrogen storage materials for various applications such as hydrogen fuel cell technology.

Hydrogen-based energy is the cleanest of the currently known energy sources, and it will undoubtedly play a part in the energy supply of this century. Heavy environmental pollution due to combustion of fossil fuel and depletion of non-renewable energy sources emerge as two serious problems. Hydrogen-based energy sources are considered to be the most promising candidates for solving these problems, as this kind of energy can replace fossil fuel in most applications. The biggest challenge in on-board hydrogen utilisation (i.e. as fuel for vehicle, portable computer, phone, etc.) is the low hydrogen storage capacity that existing systems possess. Development of hydrogen storage media is of great importance and research on this area is quite active throughout the world.
Currently, there are four systems for hydrogen storage [1, 2]: Liquid hydrogen, Compressed hydrogen gas, Cryo-adsorption system, and Metal hydride systems.
Applications of hydrogen in pure form (liquid hydrogen or compressed hydrogen gas) are mostly utilised for large-scale or stationary purposes, since the weight of containers for hydrogen is normally too prohibitive for uses where hydrogen is used in limited scope. For vehicular or any other portable applications, hydrogen stored in solid-state materials seems to be the best solution. Thus, cryo-adsorption systems and metal hydride systems are the two most promising systems.
The cryo-adsorption systems show advantages in moderate weight and volume. In this system, hydrogen molecules are physically bound to the surface of activated carbon at liquid nitrogen temperature. Under optimised conditions, the hydrogen storage capacity of activated carbon may reach 7 wt % based on the weight of activated carbon. The disadvantages of this system relate to the critical conditions required (i.e. cryogenic conditions).
Metal hydrides have been proposed as systems for hydrogen storage. Hydrogen is chemisorbed by metal or metal alloys with corresponding formation of metal hydrides. Two categories of metal alloys have been extensively explored: I) AB5 type, and ii) A2B type. LaNi5 is a good example of the first category. One molecule of LaNi5 can absorb about 6 hydrogen atoms at ambient temperature and high pressures to form LaNi5H6. Subsequent discharge of hydrogen can be achieved by reducing the hydrogen pressure. In this system, the hydrogen storage capacity is less than 1.5 wt %. The advantages of this type of metal alloy lie in the quick kinetics of hydrogen charge/discharge and the very good density of the materials, but the hydrogen storage capacity is unacceptable. Mg2Ni illustrates the A2B type of metal alloy. This kind of metal alloy can store more than 4 wt % of hydrogen, but suffers from higher operating temperature (above 300° C. for desorption, with an equilibrium hydrogen pressure of up to 1.0 bar), slow hydrogen charge and discharge kinetics and relatively low density. More recently, much effort has been made on material engineering of these metal alloys [3, 4], but no significant improvement has been made. Furthermore, the high cost of the metal alloys is another drawback.

Method for reversible storage of hydrogen and materials for hydrogen storage


A porous carbon electrode substrate hardly causes a short circuit when used in a fuel cell, and from which carbon fibers protruding from the substrate surface, carbon fibers that protrude from the substrate surface when the porous carbon electrode substrate is pressurized in a direction perpendicular to a surface thereof, and short carbon fibers that are insufficiently bonded at the substrate surface have been sufficiently removed. The porous carbon electrode substrate includes short carbon fibers and carbonized resin bonding the short carbon fibers, the porous carbon electrode substrate having an average short circuit current value measured at a first surface of 10 mA or less.

A fuel cell, for example, a polymer electrolyte fuel cell converts chemical energy of a substance directly into electric energy through an electrochemical reaction caused by supply of reaction gases (a fuel gas and an oxidant gas) through gas diffusion layers to a membrane-electrode assembly that includes a polymer electrolyte membrane sandwiched between a pair of catalyst layers.
A gas diffusion layer of a fuel cell is produced by subjecting a porous carbon electrode substrate such as carbon paper to a water repellent treatment, and has a microporous layer on a surface in contact with a catalyst layer. When monofilaments of carbon fibers of the porous carbon electrode substrate penetrate the polymer electrolyte membrane, the performance of the fuel cell may deteriorate due to a short circuit or degradation of the polymer electrolyte membrane starting from the penetrated portion. Even though the performance deterioration initially has a small influence on the power generation, repeated swelling and shrinkage of the membrane due to repetition of starting and stopping of the fuel cell advance the short circuit and degradation of the polymer electrolyte membrane to lower the durability of the fuel cell.
Therefore, Japanese Patent Laid-open Publication No. 2010-70433 discloses a method of manufacturing a porous carbon electrode substrate from which short carbon fibers not bonded with carbonized resin have been sufficiently removed through a treatment of blowing gas onto at least one surface of the porous carbon electrode substrate.
In addition, Japanese Patent Laid-open Publication No. 2012-33458 discloses a method including disposing an insulating member having a plurality of communicating holes on a water-repellent layer side of a gas diffusion layer formed by laminating a layer made of carbon fibers and a water-repellent layer, sandwiching the gas diffusion layer and the insulating member between a pair of electrodes, disposing a pair of pressure plates on back surfaces of the pair of electrodes to sandwich the electrodes, and pressurizing the gas diffusion layer with the pair of surface pressure plates. When a voltage is applied to the pair of electrodes while the gas diffusion layer is pressurized, a current is caused to flow through the protruding portion of the carbon fibers contacting the electrode on the water-repellent layer side through the communicating holes in the insulating member, and the protruding carbon fibers are burned off with Joule heat.
Meanwhile, Japanese Patent Laid-open Publication No. 2012-204142 discloses a method including disposing an elastic sheet on at least one surface of a carbon sheet including short carbon fibers bonded with carbon, pressurizing the carbon sheet at a linear pressure of 5 kN/m to 30 kN/m using a continuous pressurizing means, and then continuously removing the carbon powder adhered to the carbon sheet by a method of sweeping the carbon powder with a brush or the like, a method of sucking the carbon powder, ultrasonic cleaning or the like.
The method described in Japanese Patent Laid-open Publication No. 2010-70433, however, has the following problem: although the surface of the gas diffusion layer can be cleaned to some extent, carbon fibers newly protrude when the gas diffusion layer is compressed, for example, in a step of joining the gas diffusion layer to a polymer electrolyte membrane and, thus, the protruding carbon fibers stick into the polymer electrolyte membrane to generate a large short circuit current.
The method described in Japanese Patent Laid-open Publication No. 2012-33458 has the following problem: the carbon fibers tend to burn off in a narrow portion of protruding carbon fibers that generates a large heat, and in the middle part in the longitudinal direction of protruding carbon fibers with little heat radiation so that the carbon fibers protruding from the gas diffusion layer to the cut portion may remain, or portions of the carbon fibers protruding beyond the cut portion may be contaminated and cause a short circuit of the polymer electrolyte membrane.
The method described in Japanese Patent Laid-open Publication No. 2012-204142 also has a problem that, since an elastic sheet is disposed on at least one surface of the carbon sheet, the pressurizing force is distributed to fold the short carbon fibers, and the effect of removing the short carbon fibers is reduced.
It could therefore be helpful to provide a porous carbon electrode substrate that hardly causes a short circuit when used in a fuel cell, and from which short carbon fibers insufficiently bonded at the substrate surface have been sufficiently removed.

Porous carbon electrode substrate, method of manufacturing same, gas diffusion layer, and membrane-electrode assembly for fuel cell


The present invention provides a method and apparatus for processing substrates. A processing system includes a chamber having a top mounted pumping assembly. The chamber comprises a ceiling disposed on a chamber body and having an opening formed therein. The pumping assembly is connected to the ceiling and registered with the opening. The pumping assembly operates to evacuate the chamber to a desired pressure. One or more gases are supplied to the chamber via a gas distribution chamber and are exhausted from the chamber via the opening formed in the ceiling.

1. Field of the Invention
The present invention relates to a method and apparatus for processing substrates. Specifically, the invention relates to processing systems.
2. Background of the Related Art
Semiconductor processing typically involves the deposition and/or removal (etching) of materials from a substrate. Frequently, semiconductor processes require a vacuum environment. As a result, processing systems generally include a vacuum chamber coupled to a pumping system. The pumping system includes a vacuum pump which, when in communication with the chamber, can reduce the pressure of the enclosure defined by the vacuum chamber.
FIG. 1 is a schematic drawing of a typical processing system 100. The processing system 100 generally includes a chamber 102 having a dome-shaped top 103, a pumping module 104 and a gas delivery module 112. An opening 106 formed in the chamber body allows fluid communication between the chamber 102 and the pumping module 104. A support member 108 is disposed in the chamber 102 and provides a substrate receiving surface 110 adapted to support a substrate 111 during processing. The gas delivery module 112 is coupled to the chamber 102 via supply lines 113 and provides one or more gases to the chamber 102 during processing. A plasma generating assembly comprising a coil 115 disposed on the top 103 and a power supply 117 connected to the coil 115 is provided to generate a plasma in the chamber 102. Although not shown, the processing system 100 may include additional components known in the art such as sensors, motors, etc.
The processing system 100 is adaptable to plasma processing including etching and chemical vapor deposition (CVD). In the case of etching, etching gases are introduced into the chamber 102 and a plasma is struck by flowing a current through the coil 115. The reactive species in the plasma then etch the exposed portion of the metal, dielectric, or semiconductive material on the substrate 111. In order to maintain a desired pressure in the chamber 102, as well as remove gaseous by-products, the chamber 102 and the pumping module 104 are communicated via the opening 106. The resulting flow pattern of gases in the chamber 102 is shown by arrows 120.
One problem with conventional chambers is the non-symmetric flow of gases over the substrate being processed. Flow symmetry is important in order to ensure uniform deposition or removal of material from the substrate. The arrows 120 in FIG. 1 illustrate the non-uniform flow pattern within the chamber 102. In the case of an etching chamber for example, such a flow pattern results in a non-uniform etch rate of material from the substrate.
Another problem with conventional chambers, including etch chambers, is the potential for contamination of substrates being processed. During processing, material etched from the substrate or deposition gases introduced in the chamber deposit on the chamber surfaces and form a film thereon. Over time, such films may crack or chip under the influence of thermal stresses and gravitational forces. Portions of the film may then flake and deposit on the substrate resulting in defective devices. Issues of substrate contamination are typically addressed by periodically cleaning the chamber. For example, one or more cleaning gases may be flowed into the chamber to remove deposition from the chamber surfaces. The cleaning gases react with the deposited material to form gaseous by-products that can then be removed from the chamber by a pumping mechanism. The frequency at which a chamber is cleaned is typically referred to as the mean-wafer-between-clean (MWBC). Depending on the particular process being run in the chamber, the MWBC may be less than about one thousand wafers resulting in a significant detrimental impact on the overall throughput of the system.
One solution to the problem of contamination is to control the temperature of the chamber. Temperature control mitigates the thermal stresses that can lead to flaking and contamination. Accordingly, some processing systems, such as the one shown in FIG. 1, include a temperature control unit 124. The temperature control unit 124 in FIG. 1 is disposed around the dome 103 because deposition is typically increased on the inner surface of the dome 103. However, even where cooling units are used, particles are still generated in the chamber. Thus, conventional chambers continue to experience significant contamination of substrates. Further, temperature control units are expensive, both in the purchase price and the cost of operation. Additionally, the temperature control units typically occupy a large volume, thereby greatly increasing the amount of space needed for the processing system.
Another problem with conventional chambers is their lack of serviceability. For example, chambers are often coated with a material to prevent corrosion of chamber surfaces. The coating apparatus is typically an automated device with a pressurized fluid source and a spray nozzle. The coating apparatus is robotically actuated vertically along a central axis while simultaneously being rotated about the axis. However, due to their complex design, the chambers are not easily accessible to an automated coating apparatus. As a result, the surfaces are unevenly coated or, in some cases, not coated at all. For example, the chamber 102 typically consists of a manifold or plenum having an exhaust channel (e.g., the opening 106) formed therein. The exhaust channel extends outwardly from the body of the chamber 102 and is coupled at its end to the pumping module 104. Such an arrangement, wherein the surfaces lie along different planes and at different radii from a central axis, makes coating all surfaces of the chamber 102 with an automated device difficult.
Therefore, there is a need for a process chamber providing uniform flow of gases over a substrate while preferably mitigating the potential for contamination of the chamber and affording serviceability.
The present invention generally provides a method and apparatus for processing substrates. In one aspect of the invention, a processing system comprises a chamber having a top mounted pumping assembly. The chamber comprises a ceiling disposed on a chamber body and having an opening formed therein. The pumping assembly is connected to the ceiling and registered with the opening.
In another aspect of the invention, a chamber comprises a floor, a sidewall and an opening formed at an upper end of the chamber and a pumping assembly connected to the chamber and registered with the opening.
The chamber may further comprise a gas manifold disposed at an upper end of the chamber and defining an opening, an energy transmissive member disposed on the gas manifold, and a pumping assembly coupled to an upper end of the energy transmissive member.
In yet another aspect of the invention, an apparatus comprises a chamber body comprising a floor and a sidewall and defining an enclosure; a substrate support member disposed in the chamber body; a gas manifold disposed at an upper end of the chamber body; a fluid supply unit coupled to the gas manifold; an energy transmissive member disposed on the gas manifold and defining an opening at an upper end; a plasma generating assembly disposed about the energy transmissive member; and a pumping assembly coupled to the upper end of the energy transmissive member.
In still another aspect of the invention, a method for processing a substrate, comprises providing a chamber defining a processing region and having an opening formed at an upper end thereof; and evacuating the processing region through the opening.

Method and apparatus for plasma processing


An internal loading cylindrical air filter apparatus having a circular tubular knit pile fabric filter element extending unsupported between end plates to provide an essentially full length unobstructed filter area, and having a rotating internal suction cleaning nozzle therefor. The tubular filter element is supported at its entry end by a detachable angle ring having a cylindrical ring flange extending through an opening in the entry end plate of the apparatus to permit endwise assembly and disassembly of the fabric filter element into the apparatus. Annular or helical strands may extend in circumferential engagement with the filter element for restraining it from ballooning out of effective cleaning distance with respect to the rotating suction nozzle under heavy filtering conditions, and a crank may be provided for adjusting the extending length of a helically extending restraining strand for controlling the degree of restaint imposed on the filter element.

Internal loading cylindrical filters are well known, and U.S. Pat. No. 4,154,588 is exemplary of current developments in the art. This patent discloses a knit pile fabric filter element which is stretched in tubular form over a helically-wound metal rod support frame. The pile of the fabric is on the inside, and a lengthwise zipper is provided in the tubular fabric filter element for ease of assembly over the helical support. The small helically-travelling cleaning nozzle of the filter apparatus has been found not to be entirely suitable in applications where large quantities of fine wood and paper fiber are being recaptured for reuse after the fiber has been concentrated in smaller amounts of air by passage through a cyclone separator.
U.S. Pat. Nos. 1,944,267 and 1,944,268 disclose the only known unsupported cylindrical fabric filter elements with self-cleaning nozzles; however, in these patents the nozzles are of annular configuration and move lengthwise through the cylindrical filter elements, piston-like, and the axes of the cylindrical filter elements are in a vertical position for a "bag-house" application whereby it might be assumed that the long, narrow, heavy, woven, woolen tubular filter elements used for filtering purposes at that time would be relatively rigid, and that the piston-like movement of the cleaning nozzles therefore had no tendency to disturb the original cylindrical form of the filter element, but rather to maintain it. Moreover, the vertical disposition of the filter elements did not result in any tendency of such elements to bow at the center if not supported, as would be the case if the filter elements were arranged horizontally between two end plates.
Two additional U.S. Pat. Nos. 1,995,648 and 2,057,446, having the same inventor as the last-mentioned pair of patents, disclose vertical cylindrical filter elements in which the filter medium is a fibrous material such as steel or mineral wool, and the medium is fastened to a supporting screen or wire mesh cover for greater strength, rigidity, and durability of the filter element. In both of these patents, the cylindrical proportions of the filter elements are those of conventional drum filters, unlike bag house filter elements, and full length rotating suction nozzles serve to clean the filtered-out waste material from the interior of the filter element, with biasing means being provided to assure that the filter elements and suction nozzles stay in contact.
The present invention provides the advantage of a relatively inexpensive, very flexible knit fabric filter medium having a pile component which provides a "surface loading" filter effect wherein the pile fibers lie down as the dirty air passes through the filter element from the pile side, thereby trapping the waste dust or fibers on the surface; then, as the suction nozzle passes, the pile fibers are sucked up perpendicular to the filter element and the waste material is easily and thoroughly sucked therefrom. The knit filter element in tubular form is quite flexible and can be readily stretched taut between the end plates of the filter apparatus to assume a cylindrical shape in which the internal rotating cleaning nozzles are adjacent the knit fabric, and the filter element may be assembled in place from the ends of the filter apparatus without need for access from the sides thereof (which are usually inaccessible due to the typical "built-in" arrangement of the filter apparatus), with a unique end support structure being provided for the filter element to permit this ease of assembly. In some cases of extremely heavy waste build-up inside the filter element, the force of air passing through the knit fabric element causes it to have a tendency to "balloon" out of its normal taut cylindrical shape, and, in accordance with a further feature of the present invention, restraining circumferential flexible strands may be used to restrain the filter element from such ballooning tendencies so that the rotating nozzle may clean it suitably.

Internal loading cylindrical filter with unsupported tubular filter fabric


A debeading device for tire changing machines includes a swing arm having a hinging end hinged to a base of a tire changing machine and swinging in a swing plane between an active debeading position toward the base and an inactive position away from the base; a debeading tool supported at a free end of the arm, opposite to the hinging end; an actuator for reciprocatingly rotating the arm between the active and inactive positions, which includes an externally screw-threaded member supported by the base and rotatably actuated by a motor and screwingly/unscrewingly engaged in a matingly threaded hollow member associated with the arm.

Debeading apparatuses are known, which are mounted to a lateral side of the base of a tire changing machine and are used to detach the beads of pre-emptively deflated beads from the edges of the rim upon which they are mounted.
Typically, a prior art debeading apparatus consists of an arm with one end hinged to a hinge that is fixed to the lateral side of the base of a tire changing machine and an opposite free end with a debeading shovel.
The arm is horizontally movable about the hinge between an inactive position away from the base and an active position, progressively moving toward the lateral side of the base.
The arm is rotated by means of a fluid-dynamic, typically pneumatic actuator, whose liner is held within the base and whose shaft projects out of the base through an opening.
The shaft has its free end articulated to a median area of the arm, to push or pull the latter.
When the arm is moved in the position away from the base, the tire repairer may place a wheel with the tire preemptively deflated, in a vertical position, between the arm and the debeading shovel.
Then, the tire repairer will operate the actuator, which will draw the arm toward the base and, as a result, the shovel will first abut the tire bead, and then push it toward the interior of the rim, to the central channel thereof, thereby detaching it from the edge of the rim against which it abuts in the inflated state and as it runs on the road.
The tire repairer repeats the debeading steps, arc after arc, until it completes the circumference of one side of the wheel, then he/she turns it and completes debeading on the opposite side in the same manner.
This prior art suffers from certain drawbacks.
A first drawback is that the force developed by the fluid-dynamic actuator cannot be adjusted and causes the arm to be quasi instantaneously pulled toward the base.
Therefore, the arm shall have a substantially abrupt debeading operation, which will result in the risk of damaging the structure of tire sidewalls with the debeading shovel, i.e. tearing the fabric that typically composes it and affecting tire safety for further use.
A second drawback is that, since the debeading shovel is articulated to the free end of the arm such that it may be displaced in space during debeading, tire repairers shall manually orient it with the utmost care, at least until it contacts the tire bead, in a first area, i.e. very proximate the rim edge, which involves the risk that the latter may be contacted thereby, and damaged.
Therefore, tire repairers shall direct the orientation of the debeading shovel only using their own forces and by quick movements, to keep pace with the action of the debeading arm.
Nevertheless, in spite of the care taken by tire repairers, the force of the actuator may exceed their physical force, whereby the debeading shovel will not be properly oriented, and hence the front edge thereof will once again impact the rim edge during debeading, with the risk of damaging it.

De-beading device for tire-changing machines


Renewable energy systems extracting energy from natural water flow or wind. The energy systems are configurations of long-stroke open-channel reciprocating engines employing one or two flow engaging elements such as drogue chutes for water flow or airfoils for wind applications tethered to a power drum and useful to generate electricity or to pump water as from wells. A wind energy system using two buoyant airfoils emblazoned with advertising messages is suitable for urban deployment generating electric power and also supporting an advertising revenue stream.

xe2x80x9cDistributed Wind Power Assessmentxe2x80x9d, February 2001, National Wind Coordinating Committee, Washington D.C.
xe2x80x9cAds Put Profit in Wind Powerxe2x80x9d, Popular Mechanics, June, 2001, page 20
Wind energy conversion systems, as currently deployed, are horizontal axis turbines mounted atop towers. It has been found that there is some economy of scale as well as other advantages such as lower incidence of avian mortality and less obtrusive acoustic noise output in deploying very large units of 1.5 megawatt or even larger capacities. However, out of necessity, these are usually part of large centralized xe2x80x9cwind farmsxe2x80x9d with dedicated electrical transmission lines. Local construction of turbine blades and towers are almost required because of the difficulty of transporting the physically large sections. Often access roads to remote sites must be built for transporting the turbine and tower sections as well as for the cranes and large rigging equipment required for erection and repairs. Distributed wind power installations must use smaller turbine units which are designed to interface with existing or upgraded distribution networks at lower voltages. The rural environments compatible with distributed wind power often do not have three-phase AC distribution which is a requirement for even modest (eg.xe2x80x9450 kw) units. Needless to say, high population density areas and high buildings in urban environments, while having adequate distribution networks and ready markets, are not a good match to a technology using towers (which also precludes their attachment to existing structures due to large moment loads and vibration). No known wind energy systems are compatible with the direct generation of other forms of secondary revenue streams.
In considering extraction of energy from natural water flow such as streams, tidal flow, or river currents, the sequestering of flow behind dams or barriers has traditionally been required. This incurs large outlays of capital, and often substantial environmental impact to man and to marine life. Pressure changes and sharp rotating blades within commonly used hydro turbines are themselves a danger to fish fry. The installations for hydroelectric plants or tidal generating facilities are generally permanent and unmovable fixtures.
This invention introduces the notion of a long-stroke open-channel reciprocating engine as an alternative to the turbines presently used to extract energy from the flow of water or air. Certain features of this type of reciprocating engine are analogous to other well known reciprocating engines such as steam or internal combustion engines. For example, the functions of pistons, crankshaft, valves, and connecting rods have direct counterparts while the cylinder, a flow confining element, has no counterpart in this xe2x80x9copen-channelxe2x80x9d engine. The engine of this invention uses drogue chutes to engage water currents or airfoils to engage wind in a manner analogous to pistons. Tethers of strong fibers such as nylon or aramid attach the drogue chutes or airfoils to a periodically reversing power drum which is turned when tether unwinds, not unlike the interaction of connection rods and crankshaft. Since this is a long-stroke engine, the power drum will turn multiple revolutions during one engine stroke. Valves have a direct counterpart in control of the drogue chutes or airfoils as they are purposely switched from a high pull mode (high drag and/or lift) to a low pull mode (low drag and/or lift) or vice-versa at the end of a stroke. As in other engines with a single piston, the most simple version has a single drogue chute or airfoil which extracts mechanical energy from fluid flow as it unwinds tether from the power drum in high pull mode and then must be wound back on the power drum while in low pull mode using parasitic energy; this is a xe2x80x9csingle-actingxe2x80x9d engine which extracts net positive energy over a complete cycle, but only on alternate strokes. Slightly more complex, an engine of this invention using two drogue chutes or airfoils can extract net positive energy from fluid flow on each stroke (ie.xe2x80x94xe2x80x9cdouble-actingxe2x80x9d) since one element is always in high-pull mode while the other is in low-pull mode reversing their respective roles at the end of each stroke. The extracted mechanical energy results from the difference in pull forces between the high-pull element unwinding tether from the power drum and the low-pull element being rewound onto the power drum. The parasitic loss is still there, but the power produced is almost continuous except for the brief pause at the end of each stroke during mode switching.
For water flow applications, the reciprocating engine of this invention can extract power directly from flow without sequestering it behind barriers or dams. In fact, an engine of this invention can be simply suspended below a moored barge. A system using a single drogue chute can follow rapidly shifting water currents without entanglement. Systems using a pair of drogue chutes can better extract energy from flowing water currents where rapid direction shifts are not a problem. The cyclic opening and closing of soft fabric structures such as drogue chutes at ambient pressure pose no threat to aquatic life; such movement is also conducive to self-cleaning from encrustation as from barnacles. The fact that very large drogue chutes can be deployed at very modest capital outlay compared to that of erecting and maintaining permanent civil works for alternate approaches implies lower system costs are indicated. Note that the systems of this invention for water applications are portable; they can be moved seasonally to optimize power generation or to accommodate other seasonal uses of a particular water area.
The advantages for wind energy conversion systems of this invention over traditional wind turbines are many. One important factor is that no towers are required. Heavy base equipment such as power transmissions and generating equipment is at ground level where it can be safely maintained without climbing towers. No very large elements are needed for this invention. Even large capacity systems can be transported over normal roads or even taken up elevators and erected on building roofs since no moment loading is involved and vibration is controlled as for any large mechanical device by known techniques. Using two self-buoyant helium or hydrogen inflated airfoils or a pair of non-buoyant fabric airfoils such as flexifoils attached to buoyant aerostats, the airfoils are simply suspended in the air regardless of the amount of wind. When wind picks up, the airfoils will synchronously reciprocate by virtue of mechanisms which adjust their angle of attack to control lift and/or drag to produce low pull and high pull modes as needed. Because of the inherent safety factors and lack of towers, these systems would be more easily integrated in populated commercial or industrial areas where adequate distribution lines exist and markets for generated electric power are in the local vicinity. Thus, the wind systems of this inventions are ideal for distributed wind energy in urban environments. Because of their integration with populated areas and the opportunity available by virtue of highly visible areas on the airfoils or their aerostats, the display of commercial logos or advertising messages can constitute a second revenue stream to enhance the profitability of such wind energy systems. Besides the urban deployment, other unique factors enhance the suitability of these wind systems where wind turbines with towers cannot compete. These systems can be deployed in hurricane prone areas since the airfoils can just be reefed at ground level and secured in case of impending storms. Small systems are so compact that they can even be back-packed and instantly deployed for camping use or for powering scientific instruments in remote windy areas. Similarly, they can be used on pleasure craft or recreational vehicles. Major wind farm installations off-shore can be simply installed on moored barges, no permanent towers below water level need be erected. On a grand scale, special airfoil designs with xe2x80x9csuper-tethersxe2x80x9d can be used to extract power from the jet stream. For wind farm applications, it may be possible to locate these systems in non-picturesque areas with good wind resource that would be prohibitive to harvest due to the high towers that would be necessary with conventional wind turbines. With these systems, airfoil height is simply a function of the length of a tether.
For water pumping applications on farms, it is possible to erect simple single airfoil systems that even use non-buoyant techniques by employing a tall light weight tower that just supports an airfoil at its lowest stroke position if the wind ceases to blow. This type of system can be built locally of indigenous materials. Buoyant techniques would eliminate the need for even this light weight tower. In either case, no power drum is necessary if reciprocating motion can be used directly for powering a reciprocating pump. Simple techniques for valving of the single airfoil can be implemented using an auxiliary tether from ground level, or these systems can use a self-regulating wind turbine powered mechanism situated aloft adjacent to the airfoil. This mechanism would cyclically adjust the airfoil in high-pull and low-pull modes as long as the wind is blowing. The difference in pull force would operate the water pump in a reciprocating fashion. These systems for water pumping save money in erection costs and first costs by eliminating the high cost of towers used by conventional water pumping windmills.

Renewable energy systems using long-stroke open-channel reciprocating engines


This invention aims to provide an efficient means of performing a document search wherein relevance between plural document databases is examined. A summary making module and a search module are provided to document databases, and these are connected to a network as a server. A client obtains a relevant set of documents in a specified document database via this summary from a set of documents in the specified document database. The summary obtained is sent to another server, and a search is performed according to the summary in a document database in the server to which the summary is transferred.

This invention relates to a document searching method for changing over between plural document databases, and constructing relationships between plural document databases.
As more and more document information is converted to electronic format, a greater need is emerging to search different types of document database simultaneously. For instance, users often wish to look up dictionaries relating to newspaper articles which they may find of interest.
In the past, it was possible to perform a search independently by changing over between plural document databases, but there was no way of examining the relevancy of sets of documents in other databases to a set of documents in one particular database.
If however the search is limited to the same document database, it is possible to search other document sets within that database. In this case, sufficient search speed is often obtained by calculating the relevance between documents before searching. Even with different databases, it is possible to search plural document databases at the same time if such a calculation is performed beforehand, but since the need for calculation increases as the number of databases increases due to increasing numbers of combinations, this method is not realistic.
It is also possible to first analyze the set of key documents on the user side to compose a search input, and then search in other document databases by using the input, but in this case, the user side has to receive all the information about the set of key documents, and if the document databases are on a network, the amount of traffic would be huge.
It is therefore an object of this invention to resolve the problems inherent in existing technology by allowing a user to specify an arbitrary set of documents in an arbitrary document database, and to efficiently search sets of documents relating to this set of documents from within any particular database.
When there is a large search input as in the case of a set of key documents, instead of using all the information in the search input, it is faster to perform a search using only topic words of the search input as a summary, and this also reduces the load on the network. In the context of this specification, xe2x80x9csummaryxe2x80x9d means a xe2x80x9cset of topic words for a set of documentsxe2x80x9d.
The document databases are located on servers on a network comprising a module for building a summary by selecting topic words for a set of documents within the document database, and a module for performing a search on any arbitrary summary.
A user who performs a search specifies a set of documents via a client to a server in which an source document database is stored, and receives a summary.
Next, the summary is sent to a server where a target document database to be searched is located, and a search result is received.
As the search interface of the client, a display area for a set of documents is first provided wherein the required set of key documents can be specified, and the database to be searched can also be selected. In the client, the user then selects an interesting set of documents from among a set of documents displayed in this display area, and if necessary, changes over the document database which is to be searched.
These and other objects, features and advantages of the present invention will become more apparent in view of the following detailed description of the preferred embodiments in conjunction with the accompanying drawings.

Method of searching documents and a service for searching documents


A pump including a bore formed in a modulator block and connected with a suction port and a discharge port is provided. The pump includes a piston installed in the bore in a reciprocating movable manner and defining an inlet path therein, an inlet valve to open or close an exit-side end of the inlet path according to a position of the piston, and an outlet valve provided at one side of the bore, operations of the inlet and outlet valves being contrary to each other. The outlet valve includes a valve seat, a sleeve to surround the valve seat, an outlet ball interposed between the sleeve and the valve seat and used to open or close a path defined in the valve seat, and a valve cap provided at one side of the sleeve to isolate an interior from an exterior of the bore.

1. Field of the Invention
The present invention relates to a pump of an electronically controlled brake system, and, more particularly, to a pump of an electronically controlled brake system in which an outlet valve has a simplified configuration, thereby achieving a reduction in manufacturing costs.
2. Description of the Related Art
In general, an electronically controlled brake system has the purpose of efficiently preventing a wheel slip caused upon braking, quick start, or sudden acceleration of a vehicle. The brake system includes a plurality of solenoid valves to control a braking hydraulic pressure to be transmitted to hydraulic brakes of vehicle wheels, a pair of low-pressure and high-pressure accumulators to temporarily store an oil discharged from the hydraulic brakes, a pair of pumps provided between the low-pressure and high-pressure accumulators, the pumps being operated by a motor, and an ECU to control operations of the solenoid valves and motor. All the above elements are received in a modulator block made of aluminum.
In a vehicle having the above-described electronically controlled brake system, a braking force is selectively applied to a front axle or rear axle to regulate the hydraulic pressure to be transmitted to the wheel brakes, resulting in traveling stability of the vehicle. In this case, the pair of pumps serves to forcibly pump the low-pressure oil stored in the low-pressure accumulator to the high-pressure accumulator, so as to transfer the oil to the hydraulic brakes or master cylinder.
FIG. 1 is a sectional view showing a conventional pump of an electronically controlled brake system.
As shown in FIG. 1, the pump, which is designated by reference numeral 10, is installed in a block 1 that incorporates an oil passage and a variety of valves. An eccentric motor 2 is installed in the center of the block 1 and generates an eccentric rotating force. A bore 3 for installation of elements of the pump 10 is also formed in the block 1.
A piston 11 is installed in the bore 3, to perform rectilinear reciprocation using the eccentric force supplied from the eccentric motor 2.
The piston 11 has one end in contact with an outer circumference of an eccentric bearing (not designated by a reference numeral) of the eccentric motor 2, and the other end of the piston 11 is provided with a ball-shaped inlet valve 12.
An O-ring 13, as a seal, is fitted on an outer circumference of the piston 11. Also, an inlet path 14 for introduction of oil from a low-pressure accumulator is defined at the outer circumference of the piston 11.
The piston 11 has a hollow inner space 15, and a duct 16 is formed in the piston 11 to connect the hollow inner space 15 and the inlet path 14 with each other.
Here, the inlet valve 12 and piston 11 are elastically supported by a supporting spring 17, an entrance-side spring 18, and a return spring 19.
An outlet valve is provided at an end of the return spring 19 opposite to the inlet valve 12. The outlet valve includes an exit-side valve seat 21, a pump plug 22 caulked to the exit-side valve seat 21, and a ball-shaped closing member 24 supported in the pump plug 22 by means of an exit-side spring 23.
However, in the above-described conventional pump of an electronically controlled brake system, due to a complicated configuration of the outlet valve, in particular, of the valve seat 21, pump plug 22, etc., there is a problematic increase in manufacturing costs required for processing and assembly of the above elements.
Further, the conventional pump suffers from operation noise caused by pulsation of fluid that flows through an outlet path according to opening/closing operations of the outlet valve. The fluid pulsation also results in abnormal tactile feedback from a brake pedal.

Pump of electronically controlled brake system


A cable modem termination system (CMTS) may determine, for a plurality of cable modems served by the CMTS, a corresponding plurality of SNR-related metrics. The CMTS may assigning the modems among a plurality of service groups based on the SNR-related metrics. For any one of the modems, the CMTS may configure physical layer communication parameters to be used by the one of the modems based on a SNR-related metric of a service group to which the one of the modems is assigned. The physical layer communication parameters may include one or more of: transmit power, receive sensitivity, timeslot duration, modulation type, modulation order, forward error correction (FEC) type, and FEC code rate. The CMTS and the modems may communicate using orthogonal frequency division multiplexing (OFDM) over a plurality of subcarriers, and the physical layer communication parameters may be determined on a per-subcarrier basis.

Convention cable television networks can be inefficient and have insufficient capacity. Further limitations and disadvantages of conventional and traditional approaches will become apparent to one of skill in the art, through comparison of such systems with some aspects of the present invention as set forth in the remainder of the present application with reference to the drawings.

This patent is subject to a terminal disclaimer.

Method and system for service group management in a cable network


An electrophotographic element comprises a single aggregate photoconductive layer which contains a continuous phase that has a high glass transition temperature T.sub.g, of at least about 110.degree. C. The required high glass transition temperatures can be obtained by using compositions for the aggregate photoconductive layer that contain organic charge transport agents with high glass transition temperatures or polymer binders with high glass transition temperatures, or combinations of both. In a preferred embodiment an aggregating bisphenol A polycarbonate is used in combination with a cobinder polymer that has a high glass transition temperature. The electrophotographic element of the invention can be dried at temperatures of at least about 100.degree. C., and preferably from about 110.degree. C. to about 145.degree. C., to eliminate the solvent used in coating. The dried photoconductive layer exhibits good physical properties and excellent photographic performance, which remains stable with continued use.

Photoconductive elements, also called photoreceptors, are composed of a conducting support and at least one photoconductive layer which is insulating in the dark but which becomes conductive upon exposure to actinic radiation. To form images, the surface of the element is electrostatically uniformly charged in the dark and then exposed to a pattern of actinic radiation. In areas where the photoconductive layer is irradiated, mobile charge carriers are generated which migrate to the surface and dissipate the surface charge in such areas. The resulting charge pattern on the surface is referred to as an electrostatic latent image. The latent image can be made visible by application of a liquid or dry developer containing finely divided charged toner particles which, if desired, can be transferred and fixed to another surface such as a sheet of paper.
Numerous photoconductive materials have been described as being useful in electrophotography. These include inorganic substances, such as selenium and zinc oxide, and organic compounds, both monomeric and polymeric, such as arylamines, arylmethanes, carbazoles, pyrroles, phthalocyanines and the like. Especially useful are aggregate photoconductive compositions that have a continuous electrically insulating polymer phase containing a finely divided, particulate co-crystalline complex of at least one pyrylium-type dye salt and at least one polymer having an alkylidenediarylene group in a recurring unit.
Aggregate compositions used in photoreceptors can be prepared by several techniques, such as, for example, the "dye first" technique described in Gramza et al., U.S. Pat. No. 3,615,396, incorporated herein by reference. Alternatively, they can be prepared by the "shearing" method described in Gramza, U.S. Pat. No. 3,615,415, incorporated herein by reference. This latter method involves the high speed shearing of the photoconductive composition prior to coating and thus eliminates subsequent solvent treatment, as disclosed in Light, U.S. Pat. No. 3,615,414, referred to hereinafter. By whatever method prepared, the aggregate composition is applied with a suitable liquid coating vehicle onto a support or underlying layer to form a separately identifiable multiphase aggregate composition, the heterogeneous nature of which is generally apparent when viewed under magnification, although such compositions may appear to be uniform to the naked eye in the absence of magnification. There can, of course, be macroscopic heterogeneity. Suitably, the pyrylium type dye-salt-containing aggregate in the discontinuous phase is finely-divided, i.e., typically predominantly in the size range of from about 0.01 to about 25 .mu.m.
Photoconductive elements can comprise single or multiple active layers. In a single layer photoconductive element charge generation and charge transport take place within the same layer. Single active layer aggregate photoconductive elements are described in Light, U.S. Pat. No. 3,615,414 and in Gramza et al., U.S. Pat. Nos. 3,732,180 and 3,615,415. Contois and Rossi, U.S. Pat. Nos. 3,873,312 and 3,873,311 describe the use of aggregate photoconductive compositions and elements containing organic photoconductors with a styrylamino structure. Berwick et al., U.S. Pat. No. 4,175,960, describes a multi-active photoconductive element having an aggregate charge generation layer.
Single active layer aggregate photoconductive compositions have found many commercial applications. They are easily and inexpensively manufactured and have the additional advantage of being able to photoconduct to either a negatively or positively charged surface.
A single active layer aggregate Photoconductive composition intended for coating in a drum format differs in certain respects from one intended for web coating. In particular, drum coating requires the use of higher boiling solvents in the formulation to promote good coating uniformity. However, because the coating substrate is mounted in a vertical position during coating, drying conditions must be carefully controlled to maintain end to end thickness uniformity. Formulations for drum coatings typically contain 1,1,2-trichloroethane as a solvent, and coated drums are generally dried in a convection oven set at a temperature of about 90.degree. C. to volatilize this solvent. It would be desirable to employ higher temperatures to remove the solvent completely, but it has been found that drying temperatures above 100.degree. C. have a detrimental effect on the electrophotographic speed of a single active layer aggregate photoconductor.
Essentially solvent-free photoconductive drum coatings are desirable for several reasons. First, residual solvent is capable of plasticizing a coating, adversely affecting its physical properties and diminishing its durability. In addition, the presence of a small amount of residual solvent that is slowly volatilized with continuing use of the coating can lead to unstable electrophotographic performance.
In commercial electrophotographic copying machines, especially those of compact design where drum photoconductors are typically employed, internal temperatures increase greatly, as much as 70.degree. C., during a long run job. Because of the heat capacity and thermal conductivity of aluminum, the metal most commonly used for drum substrates, the photoconductive layer quickly equilibrates with the hot environment. Continued drying, with consequent change in the electrophotographic performance of the single active layer aggregate photoconductor, is the result.
Thus, a need exists for single active layer aggregate photoconductors, particularly in a drum format, which can be dried at a high enough temperature, at least about 100.degree. C., and preferably from about 110.degree. C. to 145.degree. C., to ensure complete removal of coating solvent and form a photoconductive layer with good physical properties and excellent, stable electrophotographic performance.

Electrophotographic element and method of making same


The present invention is directed to an isolated oligonucleotide having a nucleotide sequence which includes a sequence corresponding to SEQ ID NO:1, or which includes a sequence complementary to the sequence corresponding to SEQ ID NO:1. Methods for differentiating and/or identifying canine chromosomes using the isolated oligonucleotide are also provided. The invention further provides a method for differentiating and/or identifying canine chromosomes using a labeled repetitive probe, wherein the labeled repetitive probe is hybridized to canine chromosomes and the resulting hybrids are detected fluorescently. In one embodiment, the DNA sequence of the repetitive probe is provided in the recombinant plasmid designated pCfBE013/BH.

Throughout this application various publications are referenced, many in parenthesis. Full citations for these publications are provided at the end of the Detailed Description. The disclosures of these publications in their entireties are hereby incorporated by reference in this application.
The diploid chromosome complement of the domestic dog Canis familiaris consists of 76 acrocentric autosomes and an X-Y sex chromosome pair (Selden et al., 1975). The autosomes, in addition to being numerous, are fairly small and resemble each other even after G-banding. The technical difficulties of working on the canine autosomes due to their small size, combined with the evolutionary history of the canine karyotype as a highly derived version of the primitive carnivore karyotype (probably as a result of Robertsonian fusions--Wayne et al., 1987b), have resulted in an almost complete lack of knowledge about the comparative cytogenetics of the dog. Efforts to perform positional cloning of mutations using canine models of gene defects are seriously hampered without a knowledge of chromosomal synteny relationships between the dog and species with detailed chromosomal maps (such as man and mouse).
Previous techniques in which marking of canine autosomes have been attempted include G-banding, in situ hybridization of highly repetitive DNAs, C-banding, N-banding, and Q-banding.
Because of the small size and numerous amount of canine autosomes, two studies on the G-banded karyotype of the dog differed on the banding patterns and numbering systems for several of the autosomes (Selden et al., 1975; Manolache et al., 1976). Later reports attempted to resolve some of the inconsistencies by relying upon G-banded karyotypes from sequentially stained amethopterin synchronized lymphocyte cultures (Stone et al., 1991) or by using fibroblast cell lines of the grey wolf Canis lupus (a species with a completely homologous karyotype to the domestic dog--Wayne et al., 1987a).
The in situ hybridization studies that have been carried out on canine autosomes have been limited in scope to grain count statistics on the binding of canine satellite DNAs to the centromeric heterochromatin (Modi et al., 1988).
C-banding of the centromeric heterochromatin labels only 7 or 8 unspecified autosomes, while N-banding (silver staining indicative of nucleolar organizer regions) marked three pairs of autosomes and the Y chromosome (Pathak et al., 1982; Stone et al., 1991). Q-banding resulted in fluorescing regions which corresponded to darkly staining G-band regions, but the resolution was minimal (Stone et al., 1991).
Despite these various attempts to mark canine autosomes for identification and/or differentiation, the problems associated with the small size and numerous amounts of the canine autosomes has still hampered the development of an accurate and reproducible method for identification and/or differentiation thereof.
The development of identification methods for the canine autosomes that will permit rapid and unequivocal recognition of chromosome groups is an important first step in the comparative mapping of the canine genome. Further, these methods will ideally be capable of being applied simultaneously with the in situ hybridization of unique copy euchromatic chromosomal probes of interest from dog or other species (such as man or mouse).
In mammalian species other than man and mouse, the usefulness of the different types of repetitive probes for chromosome banding and recognition studies is difficult to predict. For example, fluorescent in situ hybridizations of Alu-like sequences to chromosome sets from pig, sheep, and cow were found to produce indistinct and diffuse hybridization patterns that were not useful for chromosome recognition (Yasue et al., 1991; Rajcan-Separovic and Sabour, 1993). By contrast, the highly repetitive C5 satellite probe from the Chinese muntjac which was found to hybridize to the centromeric heterochromatin of the Chinese muntjac and the Indian muntjac was shown to also bind to a limited number (ca. 30) of interstitial sites on the arms of only the Indian muntjac chromosomes (Lin et al., 1991).
For the dog, previous work on interspersed repetitive DNAs has been limited to the identification of a LINE element homologous to the Kpn repeat of primates (Katzir et al., 1985; Amariglio et al., 1991) and the canid-specific SINE element (Minnick et al., 1992).
It should be apparent from the above discussion that the accuracy of particular chromosome marking methods can vary between species. A successful G-banding in one species, or a successful FISH technique in a species, does not indicate that G-banding and/or FISH techniques will be successful in identifying and/or differentiating chromosomes from another different species. In view of the problems encountered in marking canine chromosomes, despite some success in marking chromosomes from other species, a need continues to exist for an accurate method for differentiating and/or identifying canine chromosomes.

Method for identifying canine chromosomes


A simulation system to determine an optimal trajectory path for a robot with an attached implement includes a trajectory simulator which provides a simulated trajectory path for an implement, an implement model database which comprises motion data of the implement, and a logger that associates a time stamp of the implement's motion during the simulated trajectory path to generate logger data. A profile is determined by the logger data received from the logger which identifies implement motion that exceeds predetermined thresholds, and a tuner adjusts the simulated trajectory path so as to reduce the number of times predetermined thresholds are exceeded.

It is well known in various industries to use robots in the assembly of large quantities of manufactured goods. Robots are used in the automated assembly of automobiles, circuit boards, computers, the manufacture of food, and many other items. Robots provide advantages over manual labor and cost savings in view of their ability to perform boring and repetitive tasks very well with minimal error.
One such task is the painting of automobile exterior body parts. Similar material dispensing robots are also used in general industries for the manufacture of airplane components, windmills, buses, trains and the like. Although robots provide a clear time savings advantage in operation, setting up a robot to perform a specific task is a cumbersome process. For example, in paint application processes, care must be taken so that desired paint coverage is obtained with minimal waste.
It will be appreciated that it is desirable to program a predetermined path, sometimes referred to as a trajectory, of a robot arm which carries an implement that performs the task as quickly and efficiently as possible. However it has been found that quick changes in implement motion result in damage to the implement. For example, it is believed that a gyroscopic effect caused by the robot reorientation (wrist motion) is one of the main reasons for a painting device's atomizer turbine to cause "touch down," wherein a rotor of the dispenser comes in contact with a stator. The turbine's bearing air "cushion" is designed to maintain spacing between the stator and rotor during operational speeds of 10,000 to 70,000 RPM. However, sudden changes in the robot's wrist motion overcomes the air cushion and results in damage to the atomizer turbine. Such damage to the turbine, which is an expensive part, results in machine downtime and less-than-ideal distribution of paint. Therefore, there is a need in the art to simulate motion of an implement carried by a robotic arm to determine where in the robot arm's trajectory path damaging dynamics take place and to adjust the path so as not to adversely affect the implement and its associated function.

System and method for determining dynamic motion data in robot trajectory


A semiconductor memory device having a redundancy circuit for remedying defective columns caused during manufacture, includes a plurality of spare memory cells for storing binary data, spare bit lines connected to the outputs of the spare memory cells, respectively, and each having two or more columns, a spare gate circuit for controlling the outputs of the spare bit lines, a circuit having storage sections for storing addresses of the defective columns, for generating a spare gate selection signal in response to one of the addresses of the defective columns and selecting a spare gate, and a circuit for prohibiting all the outputs from a column decoder in response to the spare gate selection signal. The defective columns are remedied in units of columns whose number is smaller than that of columns of the spare bit lines.

1. Field of the Invention
The present invention relates to a semiconductor memory device and, more particularly, to a redundancy circuit for remedying an error bit caused during the manufacture of the memory device.
2. Description of the Related Art
When a memory device has some defective memory cells, even if only one, it cannot be delivered as a product. However, due to the existence of debris or the like during the memory chip manufacturing process, it is very difficult to manufacture a chip so that all of its bits operate correctly. As memory micropatterning is advanced, a chip is more and more likely to be adversely affected by such debris and the like.
For this reason, a semiconductor memory employs a redundancy circuit that replaces a defective memory cell with a spare cell to remedy errors ranging from several bits to several kilo bits, thereby maintaining the entire chip as a non-defective article. The redundancy circuit replaces a bit or word line connected to a defective memory cell with a spare bit or word line connected to a spare memory cell provided in the same chip. For example, when bit lines are to be replaced, a spare column decoder having a plurality of fuses for decoding the column addresses of the bit lines is used. The fuses corresponding to the column addresses of the defective memory cell are disconnected. Then, when the addresses of the defective bit lines are input to the decoder, a selection signal is output to spare column selecting lines, thereby selecting spare bit lines. Simultaneously, a signal for selecting bit lines to which the defective memory cell is connected is disabled. As a result, the bit lines are replaced with the spare bit lines. The redundancy circuit for replacing the word lines also uses a spare row decoder having a plurality of fuses for decoding row addresses of the word lines.
In conventional memory devices, columns of memory cells, which are selected by column selection lines, are arranged in units of two (connected to four bit lines) or four (connected to 8 bit lines), for two reasons. First, the column selection lines need to be arranged at short intervals since the memory device has many small memory cells, thus having a large storage capacity. Second, it is necessary to reduce the bits of a column address by one bit, thereby to decrease the area occupied by the column decoder.
In a conventional redundancy circuit, the number of memory-cell columns, which are selected by one spare column selection line, is equal to the number of the columns which are selected by one column selection line. Hence, a spare column selection line can be substituted only for a column selection line which has a predetermined number of bit lines. Most conventional devices have only one spare column line. If they have two or more spare column lines, they would have more spare memory cells, and would inevitably have a larger chip size.
The probability D that short-circuiting between any adjacent two bit lines in the conventional circuit described above cannot be remedied, is given by the following equation. ##EQU1##
where Nsbl: the number of spare bit lines
Nbl: the total number of bit lines excluding spare bit lines
For example, when the number of spare bit lines Nsbl is 4 and the total number of lines excluding spare bit lines Nbl is 8, .beta.=1/7. Namely, when each memory chip has one short-circuited portion, one out of every seven memory chips is estimated to be incapable of being remedied. In order to remedy such inter-bit line short-circuiting, a large number of spare column decoders must be provided, resulting in the increase in spare memory cells and considerable increase in chip area. Manufacturing cost also augments.

Redundancy circuit having a spare memory block replacing defective memory cells in different blocks


An ignition system for an internal combustion engine. The ignition system comprises a pulser for generating positive and negative output pulses responsive to the rotation of the engine, a DC power source and an ignition coil having a primary coil connected across the DC power source via a controllable current switching element. The system further comprises a control circuit for controlling the switching element which includes triangular wave generators for generating different triangular wave signals in response to the positive and negative output pulses of the pulser, respectively, a first comparator for comparing a first output signal of one triangular wave generator with a signal which is formed by multiplying a second output signal of the other triangular wave generator by a constant and adding it with a fixed voltage, and a second comparator for comparing the second output signal with a signal which is formed by multiplying the first output signal by a constant and adding it with a fixed voltage. Output terminals of the first and second comparators are connected to the controllable switching element for the ignition primary coil, whereby the output of one comparator controls the conduction start position of primary coil current of the ignition coil and the output of the other comparator controls the ignition position.

1. Field of the Invention
This invention relates to an ignition system for internal combustion engines and more particularly to an ignition system which performs the advancement of ignition angle electronically.
2. Description of Prior Art
It is disclosed in U.S. Pat. No. 3,202,146 patented Aug. 24, 1965 and entitled "STATIC TRANSISTORIZED IGNITION SYSTEM" that a monostable multivibrator is used to turn on a final stage power transistor for a fixed period. This prior art system is advantageous in that the generation of spark is stable for low and high rotation speeds of the engine and current consumption is reduced at low rotation speed since the primary current is always passed to the ignition coil for the fixed period, but it is disadvantageous in that the ignition position tends to become irregular owing to irregular operation of the monostable multivibrator since the ignition is started after the conduction start position has been determined and the monostable multivibrator has reached its quasi-stable state. Further, if the pulsating rotation during low speed operation causes the engine rotation to decrease rapidly near the upper dead point of the engine, an excessively early ignition position results.
One may refer to U.S. Pat. No. 3,587,552 patented June 28, 1971 and entitled "AUTOMATIC ADVANCE ELECTRONIC IGNITION DEVICE FOR INTERNAL COMBUSTION ENGINES" as another relevant prior art. This prior art employing a monstable multivibrator for turning off a final stage power transistor of an ignition control circuit for a fixed period is, however, disadvantageous in that the current conduction rate is large at low engine rotation speed with current consumption maximized so that heat generation in the ignition coil and the power transistor is increased.

Ignition system for internal combustion engines


A limiting factor in the operating speed of a bit-serial integrated circuit is the stray capacitance associated with interconnections of functional elements on the integrated circuit, which stray capacitance tends to be significantly larger than capacitances at signal nodes internal to a functional element. To overcome the limitations imposed by the capacitance associated with the interconnections, bit-serial signals are coupled from one functional element to another by multiplexing circuitry which splits the bit-serial signal provided by a functional element into parallel bit-serial-signals of lesser bit-rate, and then recombines the parallel signals for application to another functional element.

Progress in integrated circuit technology has fostered digital signal processing systems (DSP's) for performing functions which heretofore were performed in the analog signal domain. Examples of such DSP's are digital television receivers, compact disc players and digital video interactive (DVI) systems.
There are two basic types of DSP's which are parallel bit systems, and bit-serial systems. Typically, parallel-bit systems have been employed for all systems processing relatively wide bandwidth signals because system operating rates are lower. That is, for a given sample bit width N, the parallel-bit systems operate at 1/N.sup.th the rate of bit-serial systems. However, the parallel-bit systems require significantly more circuitry than the bit-serial systems. Because of the greater complexity and larger power dissipation of parallel-bit systems it is desirable to realize many of the wide band systems with bit-serial circuitry. Unfortunately, the processing rates of such bit-serial systems are near or exceed the limit of current technologies.
Consider a video signal processing system operating at sample rates of 14.32 MHz with samples having bit-widths of 8 bits. A bit-serial system for processing such a signal must operate at clock rates of at least 115 MHz. Desirably the system will be realized in metal-oxide-semiconductor (MOS) technology because of its higher circuit density and lower power requirements. However, signal processing rates of 115 MHz tend to be very near the limit of current MOS technology.
One of the limiting factors is manifested by timing errors, particularly between different functional elements of a particular system. These errors result from the relatively low drive capability of MOS transistors. Nominally all of the functions on an DSP integrated circuit (IC) are operated synchronously with common clock signals. Now if an interconnection between functional elements tends to be longer than typical interconnections within a functional element, it will exhibit a larger capacitance. This larger capacitance can load the output of a functional element causing timing errors between elements and thus limit the speed of the overall system. Even within a functional element, connections may exist which exhibit a capacitance of sufficient value to create timing errors.
The present invention advantageously circumvents the adverse consequences of large interelectrode capacitances in bit-serial systems, thereby increasing the overall processing rate of such systems.


Methods and apparatus for selective one-step nitridation of semiconductor substrates is provided. Nitrogen is selectively incorporated in silicon regions of a semiconductor substrate having silicon regions and silicon oxide regions by use of a selective nitridation process. Nitrogen containing radicals may be directed toward the substrate by forming a nitrogen containing plasma and filtering or removing ions from the plasma, or a thermal nitridation process using selective precursors may be performed. A remote plasma generator may be coupled to a processing chamber, optionally including one or more ion filters, showerheads, and radical distributors, or an in situ plasma may be generated and one or more ion filters or shields disposed in the chamber between the plasma generation zone and the substrate support.

As logic devices continue to scale down according to Moore's Law, processing challenges develop. One such challenge arises in floating gate (FG) NAND flash memory chips, which feature transistors that incorporate two gate elements, a control gate and a floating gate, to enable each transistor to assume more than one bit value. FG NAND memory forms the basis of most USB flash memory devices and memory card formats used today.
As critical dimensions of FG NAND devices shrink, the geometry of the various components becomes more challenging for manufacturers. Aspect ratios rise and uniformity, tolerance, and reliability issues proliferate. With NAND flash memory increasing in popularity as a convenient storage medium, there is a need for improved manufacturing processes to overcome scaling challenges particular to NAND flash devices.

Method and apparatus for single step selective nitridation