The present invention provides Ras modulators including inhibitors and/or antagonists of Ras, Ras binding, and Ras-dependent cell signaling activity. Also provided are methods of utilizing the Ras modulators as therapeutics.

Many well-validated oncology targets regulate signaling pathways through interactions with other proteins. Addressing these targets, which often lack suitable small molecule binding sites, requires larger and more complex molecules that are capable of binding relatively large or flat surfaces.
The Ras oncogene family is one such group of targets. The name "Ras" is an abbreviation of 'Rat sarcoma', reflecting the way the first members of the protein family were discovered. The name Ras is also used to refer to the entire family of genes encoding those proteins related to the transforming genes of mammalian sarcoma retroviruses. These viruses were discovered originally in rats during the 1960s (Harvey J J (1964), Nature 204 (4963): 1104-5; Kirsten W H, et al., (1970), Bibl Haematol (36): 246-9; Cooper G M (1982), Science 217 (4562): 801-6; Santos E, et al., (1982), Nature 298 (5872): 343-7; Parada L, et al., (1982), Nature 297 (5866): 474-8; Taparowsky E, et al., (1982), Nature 300 (5894): 762-5).
The Ras protein family members belong to a class of protein called small GTPases, which can bind GTP and GDP and are involved in transmitting signals within cells (cellular signal transduction).
There are three canonical members of the Ras gene family (Wong-Staal F, et al., (1981) Science 213 (4504): 226-8), designated H-Ras, N-Ras and K-Ras, and each encode extremely similar proteins made up of chains of 188 to 189 amino acids. Alternative splicing of K-Ras pre-mRNA results in the production of K-Ras isoforms K-Ras4A and K-Ras4B
At least five different mutations in H-Ras (also known as transforming protein p21) have been shown to cause Costello syndrome, a disease characterized by increased growth at the prenatal stage, growth deficiency at the postnatal stage, predisposition to tumor formation, mental retardation, skin and musculoskeletal abnormalities, distinctive facial appearance and cardiovascular abnormalities. Defects in this gene are also implicated in a variety of cancers, including bladder cancer, follicular thyroid cancer, and oral squamous cell carcinoma. Multiple transcript variants, which encode different isoforms, have been identified for this gene.
K-Ras, a Kirsten rat sarcoma viral oncogene homolog from the mammalian ras gene family, encodes a protein that is a member of the small GTPase superfamily and is usually tethered to cell membranes due to the presence of an isoprenyl group on its C-terminus. Importantly, a single amino acid substitution is responsible for an activating mutation. The transforming protein that results is implicated in various malignancies, including lung adenocarcinoma, mucinous adenoma, ductal carcinoma of the pancreas and colorectal carcinoma.
Several germline K-Ras mutations have been found to be associated with Noonan syndrome and cardio-facio-cutaneous syndrome, whereas somatic K-Ras mutations are found at high rates in leukemias, colon cancer, pancreatic cancer and lung cancer (Schubbert S, et al. (2006) Nat. Genet. 38 (3): 331-6; Niihori T, et al. (2006), Nat. Genet. 38 (3): 294-6; Burmer G C, Loeb L A (1989), Proc. Natl. Acad. Sci. U.S.A. 86 (7): 2403-7; Almoguera C, et al., (1988), Cell 53 (4): 549-54; Tam I Y, et al. (2006), Clin. Cancer Res. 12 (5): 1647-53).
A third Ras gene was discovered in 1982 and named N-Ras, for its initial identification in human neuroblastoma cells (Marshall C J, et al., (1982), Nature 299 (5879): 171-3; Hall A, et al., (1983), Nature 303 (5916): 396-400; and Shimizu K, et al., (1983), PNAS 80 (2): 383-7).
Despite the enormous amount of research focused on the Ras family over the more than 30 years since its discovery, these targets are still considered essentially undruggable.
Therefore, there is a need for the development of compounds capable of selectively binding to and/or blocking Ras or Ras-mediated signaling pathways toward the treatment of diseases such as cancer and those mediated by mutant forms of Ras and/or aberrant Ras signaling.


A process for treating drilling fluids which are used during the process of drilling for fossil fuels includes providing a drilling fluid having a continuous hydrocarbon phase, a discontinuous aqueous phase, and a discontinuous solid phase, a polymer solution, at least one coagulant, water, and oil, the oil and water being provided in a volume ratio being from 0.7 to 1.3 times the oil-to-water volume ratio of the drilling fluid. The drilling fluid is mixed with the coagulant, the polymer solution, the oil, and the water in any order to provide an input fluid. The mixture is centrifuged to separate solid materials from the input fluid to provide a treated drilling fluid.

1. Field of the Invention
The present invention relates to processes and apparatuses for treating drilling fluids for fossil fuel wells.
2. Brief Description of the Prior Art
During the process of drilling for fossil fuels, the rock formations that are being penetrated by the drilling bit creates drilled cuttings which, to varying degrees and amounts, eventually disintegrate into smaller drilled cuttings, referred to as drilled solids that become an undesirable component of such water phase continuous ("WBM"), or hydrocarbon phase continuous drilling fluids and which convey the drilled cuttings to the surface of the earth and where they are removed, to varying degrees and amounts by one or more types of cuttings and solids removal equipment.
Additionally, in order to contain the fluids within the formations being drilled, it is often necessary to supplement the drilling fluid with weighting agents such as barite, hematite, galena, calcium carbonate, etc., which are similar in size to the drilled solids and for which the specific gravity of said weighting agents is approximately equal to, or greater than the specific gravity of the drilled solids. Because the drilled solids are undesirable and they are small in size, to varying degrees of success, they are commonly removed from the drilling fluid using a decanting centrifuge.
For WBMs, a solids removal process, commonly referred to as "stripping" or "dewatering", or "enhanced centrifuging", is used to enhance the removal of both the water-wet drilled solids and water-wet weighting agents to varying degrees using a decanting centrifuge's principle of solid-liquid separation. However, for an hydrocarbon phase continuous drilling fluid in which the water phase is discontinuous and for which the solid phase is purposely oil wet to maintain such drilling fluid's rheological properties and to prevent such drilling fluid's water phase from becoming the continuous phase (a phenomenon commonly referred to as "flipping"), such a process has not been successfully developed. In some prior processes for removal of solids from hydrocarbon phase continuous drilling fluids employ coagulants and flocculants are used to contact the particulate matter directly without being dissolved a priori. In other prior art processes from the removal of solids from hydrocarbon phase continuous drilling fluids the wettability of the particulate matter is altered from being oil wet to being water wet before the particulate is contacted by any coagulants or flocculants. However, there is a continuing need for a process for the efficient removal of solids from hydrocarbon phase continuous drilling fluids.

Process and apparatus for treating drilling fluid


A female electric terminal assembly includes a body, a first beam extending from the body, and a second beam extending from the body. A channel is defined between the first beam and the second beam. A clamp is attached to the body and applies a force to bias the first beam and the second beam into the channel. A gap is maintained between the first beam and the second beam.

The present invention relates in general to an electrical terminal and, more specifically, to a female electrical terminal designed for controlling the force required to insert a corresponding male terminal.
Electrical connectors may be used in automobiles, for example, in completing electrical circuits with components in a power distribution box or connecting a wiring harness to an electrical device. These connectors may include a female terminal and a corresponding male terminal. The female terminal includes opposed beams that are biased into engagement with the male blade. The female terminal is typically made from a material having desirable electrical conductivity, such as copper. Additionally, the female terminal may include a spring feature that helps bias the beams into engagement with the blade in order to maintain strong contact between the female terminal and the male terminal. By biasing the beams into engagement with the blade, the amount of force required to insert the male blade between the beams is increased. It would be advantageous to have a female electrical terminal that allows greater control over the magnitude of the required insertion force while still maintaining strong contact between the female terminal and the male terminal.

Female electric terminal with gap between terminal beams


Provided is an X-ray generator which includes:

Generally, in a transmission type X-ray generator which emits electrons at a transmission target and makes an X-ray be generated, X-ray generation efficiency is significantly low. When electrons are accelerated to high energy and emitted at the transmission target to make an X-ray be generated, the ratio of energy of electrons that becomes the X-ray is only 1% or less of the entire electrons colliding with the transmission target: the rest, about 99% or more, of the electrons becomes heat. Therefore, improvement in X-ray generation efficiency is required. When the electrons collide with the transmission target, reflected electrons are generated. It is known that the reflected electrons do not contribute to generation of the X-ray.
PTL 1 discloses an X-ray tube with improved X-ray generation efficiency. X-ray generation efficiency is improved in the following manner: an anode member provided with a conical channel of which opening diameter is reduced from an electron source toward a target is disposed between the electron source and the target; and electrons are made to be elastically scattered on a channel surface and enter the target.
PTL 2 discloses a transmission X-ray target in which target metal is formed on a ceramic or glass X-ray transmission window substrate.

X-ray generator and X-ray imaging apparatus

Abstract: an electron path 8; a target 9c disposed on a substrate 9a, in which electrons having passed through the electron path 8 are made to emit at the target 9c and to generate an X-ray, wherein: the target 9c is disposed at the central area of the substrate 9a; at least a part of a peripheral area of the substrate 9a which is not covered with the target 9c has higher transmittance than that of the central area of the substrate 9a covered with the target 9c, with respect to the X-ray generated when electrons having reflected from the target enter an inner wall of the electron path. X-ray generation efficiency may be improved by effectively using electrons reflected off the target 9c.


The present disclosure describes an improved multi-stage noise shaping (MASH) analog-to-digital converter (ADC) for converting an analog input signal to a digital output signal. In particular, a full delta-sigma (ΔΣ) modulator is provided at the front-end of the MASH ADC, and another full ΔΣ modulator is provided at the back-end of the MASH ADC. The front-end ΔΣ modulator digitizes an analog input signal, and the back-end ΔΣ modulator digitizes an error between the output of the front-end ΔΣ modulator and the (original) analog input signal. In this configuration where the back-end modulator digitizes the error of the (full) front-end modulator, some design constraints of the front-end are relaxed. These design constraints include thermal noise, digital noise cancellation filter complexity (the quantization noise of the front-end is already shaped by the noise transfer function of the front-end), and/or non-linearity.

In many electronics applications, an analog input signal is converted to a digital output signal (e.g., for further digital signal processing). For instance, in precision measurement systems, electronics are provided with one or more sensors to make measurements, and these sensors may generate an analog signal. The analog signal would then be provided to an analog-to-digital converter (ADC) as input to generate a digital output signal for further processing. In another instance, in a mobile device receiver, an antenna generates an analog signal based on the electromagnetic waves carrying information/signals in the air. The analog signal generated by the antenna is then provided as input to an ADC to generate a digital output signal for further processing.
Analog-to-digital converters (ADCs) based on delta-sigma (ΔΣ) modulation (referred to herein as "ΔΣ modulators" or "ΔΣ ADCs" interchangeably) have been widely used in digital audio and high precision instrumentation systems. ΔΣ modulators usually provides the advantage of being able to convert an analog input signal to a digital signal with high resolution at low cost. Typically, a ΔΣ ADC encodes an analog signal using a ΔΣ modulator (e.g., using a low resolution ADC such as a 1-bit ADC, Flash ADC, Flash quantizer etc.) and then, if applicable, applies a digital filter to the output of the ΔΣ modulator to form a higher-resolution digital output. A loop filter may be provided to provide error feedback the ΔΣ modulator. One key characteristic of a ΔΣ modulator is its ability to push the quantization noise to higher frequencies, also referred to as noise shaping. As a result, ΔΣ ADCs are generally able to achieve high resolution analog-to-digital conversion. Due to its popularity, many variations on the ΔΣ ADC and structures employing the ΔΣ ADC have been proposed.
Overview
The present disclosure describes an improved multi-stage noise shaping (MASH) analog-to-digital converter (ADC) for converting an analog input signal to a digital output signal. In particular, a full delta-sigma (ΔΣ) modulator is provided at the front-end of the MASH ADC, and another full ΔΣ modulator is provided at the back-end of the MASH ADC. The front-end ΔΣ modulator digitizes an analog input signal, and the back-end ΔΣ modulator digitizes an error between the output of the front-end ΔΣ modulator and the (original) analog input signal. In this configuration where the back-end modulator digitizes the error of the (full) front-end modulator, some design constraints of the front-end are relaxed. These design constraints include thermal noise, digital noise cancellation filter complexity (the quantization noise of the front-end is already shaped by the noise transfer function of the front-end), and/or non-linearity.

Multi-stage noise shaping analog-to-digital converter


A method of using veratridine to inhibit nerve impulses, and a composition of matter including veratridine and epinephrine, is provided. Application of veratridine proximal to a nerve causes depolarization of the nerve membrane, thereby blocking transmission of nerve impules. C-fiber selectivity is demonstrated in vitro in rabbit vagus nerves. Veratridine displays extended anesthetic activity over long periods of time when compared to similar local anesthetics, with no local toxicity. Systemic toxicity is reduced by co-injection with epinephrine.

Local anesthetics are drugs that block nerve conduction when applied locally to nerve tissue in appropriate concentrations. Generally, they act on any part of the nervous system and on every type of nerve fiber. Thus, a local anesthetic in contact with a nerve trunk can cause both sensory and motor paralysis in the area innervated. A preferred practical characteristic of compounds that are termed local anesthetics is that their action is reversible; i.e., that their use is followed by complete recovery of nerve function with no evidence of structural damage to nerve fibers or cells.
A suitable local anesthetic should combine several properties. It should not be irritating to the tissues to which it is applied, nor should it cause any permanent damage to nerve structure. Its systemic toxicity should be low because it is eventually absorbed from its site of application. The ideal local anesthetic must be effective regardless of whether it is injected into a tissue or applied locally to mucous membranes. It is usually important that the time required for the onset of anesthesia should be as short as possible. Furthermore, the action must last long enough to allow time for the contemplated surgery, yet not so long as to entail an extended period of recovery. Occasionally, a local anesthetic action lasting for days or even weeks or months is desirable, for example, in the control of chronic pain. Unfortunately, the available compounds employed for anesthesia for such long duration have high local toxicity. Neurolysis with slough and necrosis of surrounding tissues occur, and partial or complete transverse injury of the spinal cord with permanent paralysis may result if such a reaction occurs in the vicinity of the cord.
Local anesthetics prevent the generation and the conduction of the nerve impulse. Their main site of action is the cell membrane, since conduction block can be demonstrated in giant axons from which the axoplasm has been removed.
Local anesthetics block conduction by decreasing or preventing the enlarged transient increase in the permeability of excitable membranes to Na.sup.+ that is produced by a slight depolarization of the membrane (see Strichartz, G. R., and Ritchie, J. M., "The action of local anesthetics on ion channels of excitable tissues," in Local Anesthetics (Strichartz, G. R., ed.), Handbook of Experimental Pharmacology, Vol. 81, Springer-Verlag, Berlin, pp. 21-53 (1987)). This action of local anesthetics is due to their direct interaction with voltage-sensitive Na.sup.+ channels. As the anesthetic action progressively develops in a nerve, the threshold for electrical excitability gradually increases, the rate of rise of the action potential declines, impulse conduction slows, and the safety factor for conduction decreases. These factors decrease the probability of propagation of the action potential, and nerve conduction fails.
Although a variety of physicochemical models have been progosed to explain how local anesthetics achieve conduction block (see Courtney, K. R., and Strichartz, G. R., "Structural elements which determine local anesthetic activity," Id., pp. 53-94), it is now generally accepted that the major mechanism of action of these drugs involves their interaction with a specific binding site within the Na.sup.+ channel. However, whether or not all actions of local anesthetics are mediated by a common site remains unclear (Courtney and Strichartz, supra; Strichartz and Ritchie, supra).
Biochemical, biophysical, and molecular biological investigations during the past decade have led to a rapid expansion of knowledge about the Na.sup.+ channel and other voltage-sensitive ion channels (see Catterall, W. A., "Structure and function of voltage-sensitive ion channels," Science 242:50-61 (1988); Trimmer, J. S., and Agnew, W. S., "Molecular diversity of voltage-sensitive Na channels," Annu. Rev. Physiol. 51:401-418 (1989)). The Na.sup.+ channel of the mammalian brain is a heterotrimeric complex of glycosylated proteins with an aggregate molecular size in excess of 300,000 daltons; the individual subunits are designated .alpha. (260 kilodaltons), .beta..sub.1 (36 kilodaltons), and .beta..sub.2 (33 kilodaltons). After incorporation of the purified polypeptides into phospholipid vesicles, sodium flux into these vesicles occurs in response to veratridine, a substance known to cause persistent activation of Na.sup.+ channels. Only the .alpha. subunit is required to reconstitute channel function. Movement of Na.sup.+ into the vesicles is blocked by the neurotoxins tetrodotoxin and saxitoxin, and by local anesthetics (Tamkun et al., "The sodium channel from rat brain; reconstitution of neurotoxinactivated ion flux and scorpion toxin binding from purified components," J. Biol. Chem. 259:1676-1688 (1984)). The hydrophilic neurotoxins probably bind within the mouth of the channel which is formed by the .alpha. subunit. By use of a nonpermeant quaternary analog of lidocaine, it is possible to show that local anesthetics and tetrodotoxin interact at opposite ends of the Na.sup.+ channel (Rosenberg et al., "Reconstitution of neurotoxin-modulated ion transport by the voltage-regulated sodium channel isolated from the electroplax of Electrophorus electricus," Proc. Natl. Acad. Sci. USA 81:1239-1243 (1984)). A simple model of the Na.sup.+ channel in the plasma membrane is shown in FIG. 1.
It is well known that different nerve fiber types have varying relative susceptibilities to conduction block produced by local anesthetics. The various fiber types are generally classifiable into type A, type B, and type C. Generally, the greater the diameter of a given nerve fiber, the greater its speed of conduction. The larger axons are concerned with proprioceptive sensation and somatic motor function, while the smaller axons subserve temperature and pain sensation and autonomic function. In Table 1, the various fiber types are listed with their diameters, electrical characteristics, and functions.
TABLE 1 __________________________________________________________________________ Nerve Fiber Types in Mammalian Nerve Absolute Fiber Conduction Spike Refractory Diameter Velocity Duration Period Fiber Type Function (.mu.m) (ms) (ms) (ms) __________________________________________________________________________ A .alpha. Proprioception; 12-20 70-120 0.4-0.5 0.4-1 somatic motor .beta. Touch, pressure 5-12 30-70 .gamma. Motor to muscle 3-6 15-30 spindles .delta. Pain, temperature, 2-5 12-30 touch B Preganglionic <3 3-15 1.2 1.2 autonomic C dorsal root Pain, reflex 0.4-1.2 0.5-2 2 2 responses sympathetic Postganglionic 0.3-1.3 0.7-2.3 2 2 sympathetics __________________________________________________________________________
In addition to variations in the speed of conduction and fiber diameter, the various classes of fibers in peripheral nerves differ in their sensitivity to hypoxia (Table 2). This fact has clinical as well as physiologic significance. Pressure on a nerve can cause loss of conduction in motor, touch, and pressure fibers while pain sensation remains relatively intact.
TABLE 2 ______________________________________ Relative Susceptibility of Mammalian A, B, and C Nerve Fibers to Conduction Block Produced By Various Agents Most Inter- Least Susceptible mediate Susceptible ______________________________________ Sensitivity to hypoxia B A C Sensitivity to pressure A B C ______________________________________
The differential rate of block exhibited by fibers of varying sizes is of great practical importance and may explain why local anesthetics affect the sensory functions of a nerve in a predictable order. Fortunately for the patient, the sensation of pain is usually the first modality to disappear; it is followed in turn by the sensations of cold, warmth, touch, and deep pressure, although individual variation is great.
The degree of block produced by a given concentration of local anesthetic depends markedly on how much and how recently the nerve has been stimulated. Thus, a resting nerve is much less sensitive to a local anesthetic than one that has been recently and repetitively stimulated; the higher the frequency of preceding stimulation, the greater is the degree of block obtained to a test shock. These frequency and use dependent effects of local anesthetics seemingly occur because the local anesthetic molecule in its protonated or charged form gains access to its binding site only when the Na.sup.+ channel is in an open state and because the local anesthetic may bind more tightly to and stabilize the inactivated state of the Na.sup.+ channel (see Courtney and Strichartz, supra). Measurements of single channel events show that voltage dependent activation is immediately followed by formation of an inactivated state. It is this transition that closes the channel (Aldrich et al., "A reinterpretation of mammalian sodium channel gating based on single channel recording," Nature 306:436-441 (1983)). Once bound, the local anesthetic greatly restricts the conformational changes in the sodium channel that underlie activation (Butterworth, J. F., and Strichartz, G. R., "Molecular mechanisms of local anesthesia: a review," Anesthesiology (1990, in press).
Veratridine is a classic activator of the voltage-gated Na.sup.+ channel. Veratridine binds to and selectively stabilizes an open conformation of the Na.sup.+ channel, leading to a persistent increase in Na.sup.+ permeability and a concomitant membrane depolarization. Veratridine binding and the associated depolarization are antagonized competitively by local anesthetics, and in principle, local anesthetic binding should be antagonized by veratridine.
Veratridine is a member of the veratrum alkaloids. The veratrum alkaloids constitute an abundant group of steroid-like polycyclic nitrogen-containing ring structures found in liliaceous plants. The alkaloids in two veratrum species, Veratrum album, Linn, and Veratrum viride, Aiton, and the species Schoenocaulon officinale, Gray, have been perhaps the best characterized, although as many as 20 different alkaloids have been identified to date (Krayer, O., and Acheson, G. M., Physiol. Rev. 26:336-446 (1946); Krayer, O., "Veratrum Alkaloids" in Pharmacology in Medicine, V. A. Drill (ed.), McGraw-Hill, N.Y. (1958)).
Veratridine, one of the major alkaloid components of veratrine, which is extracted from the seeds of Schoenocaulon officinale, the "Sabadilla seeds," has been widely used as a neuropharmacological tool to study the electrical properties of nerve and muscle fibers. Ulbricht, W., Rev. Physiol. 61:18-71 (1969); Ohta, M., et al., J. Pharmacol. Exp. Ther. 184:143-154 (1973); Catterall, W. A., Ann. Rev. Pharmacol. Toxicol. 20:15-43 (1980). Its ability to depolarize cells by altering the membrane-associated sodium channels is now well documented. Ulbricht, supra.
Aside from the well known use of veratridine as a sodium channel activator, veratridine has also been investigated as a potential hypotensive agent. Aviado, Domingo M., Pharmalogic Principles of Medical Practice, Williams & Wilkins, Baltimore, p. 548 (1972). Veratridine has also been reported as a selective inhibitor of angiotensin II receptors. Ball, D., et al., "Veratridine, Angiotensin Receptors and Aldosteronogenesis in Bovine Adrenal Glomerulosa Cells," Clin. and Exper. Theory and Practice A8(3):323-345 (1986).

A composition and a method of using veratridine and epinephrine as a local anesthetic


The present invention is directed to a fuel cell system with various features for optimal operations of an electronic device. The fuel cell system includes a fuel cartridge with a fuel reservoir containing fuel and a membrane electrode assembly (MEA) or a stack. The fuel cartridge is selectively operatively associated with the electronic device to power the device. In one embodiment, the fuel cartridge may be received within a chamber in the electronic device. In another embodiment, the fuel cartridge may be operatively associated with the electronic device while external thereto.

Fuel cells are devices that directly convert chemical energy of reactants, i.e., fuel and oxidant, into direct current (DC) electricity. For an increasing number of applications, fuel cells are more efficient than conventional power generation, such as combustion of fossil fuel and more efficient than portable power storage, such as lithium-ion batteries.
In general, fuel cell technologies include a variety of different fuel cells, such as alkali fuel cells, polymer electrolyte fuel cells, phosphoric acid fuel cells, molten carbonate fuel cells, solid oxide fuel cells and enzyme fuel cells. Some fuel cells utilize compressed hydrogen (H2) as fuel. Compressed hydrogen is generally kept under high pressure, and is therefore difficult to handle. Furthermore, large storage tanks are typically required and cannot be made sufficiently small for consumer electronic devices. Proton exchange membrane (PEM) fuel cells use methanol (CH3OH), sodium borohydride (NaBH4), hydrocarbons (such as butane) or other fuels reformed into hydrogen fuel. Conventional reformat fuel cells require reformers and other vaporization and auxiliary systems to convert fuel to hydrogen to react with oxidant in the fuel cell. Recent advances make reformer or reformat fuel cells promising for consumer electronic devices. Other PEM fuel cells use methanol (CH3OH) fuel directly ("direct methanol fuel cells" or DMFC). DMFC, where methanol is reacted directly with oxidant in the fuel cell, is the simplest and potentially smallest fuel cell, and also has promising power application for consumer electronic devices. Solid oxide fuel cells (SOFC) convert hydrocarbon fuels, such as butane, at high heat to produce electricity. SOFC requires relatively high temperature in the range of 1000° C. for the fuel cell reaction to occur.
The chemical reactions that produce electricity are different for each type of fuel cell. For DMFC, the chemical-electrical reaction at each electrode and the overall reaction for a direct methanol fuel cell are described as follows:
Half-reaction at the anode:CH3OH+H2O→CO2+6H++6e−
Half-reaction at the cathode:1.5O2+6H++6e−→3H2O
The overall fuel cell reaction:CH3OH+1.5O2→CO2+2H2O
Due to the migration of the hydrogen ions (H+) through the PEM from the anode to the cathode and due to the inability of the free electrons (e−) to pass through the PEM, the electrons must flow through an external circuit, thereby producing an electrical current through the external circuit. The external circuit may be used to power many useful consumer electronic devices, such as mobile or cell phones, calculators, personal digital assistants, laptop computers, and power tools, among others.
DMFC is discussed in U.S. Pat. Nos. 5,992,008 and 5,945,231, which are incorporated herein by reference in their entireties. Generally, the PEM is made from a polymer, such as Nafion® available from DuPont, which is a perfluorinated material having a thickness in the range of about 0.05 mm to about 0.50 mm, or other suitable membranes. The anode is typically made from a Teflonized carbon paper support with a thin layer of catalyst, such as platinum-ruthenium, deposited thereon. The cathode is typically a gas diffusion electrode in which platinum particles are bonded to one side of the membrane.
Another fuel cell reaction for a sodium borohydride reformer fuel cell is as follows:NaBH4 (aqueous)+2H2O→(heat or catalyst)→4(H2)+(NaBO2)(aqueous)
Half-reaction at the anode:H2→2H++2e−
Half-reaction at the cathode:2(2H++2e−)+O2→2H2OSuitable catalysts for this reaction include platinum and ruthenium, and other metals. The hydrogen fuel produced from reforming sodium borohydride is reacted in the fuel cell with an oxidant, such as O2, to create electricity (or a flow of electrons) and water byproduct. Sodium borate (NaBO2) byproduct is also produced by the reforming process. A sodium borohydride fuel cell is discussed in U.S. published patent application No. 2003/0082427, which is incorporated herein by reference.
One of the more important features for fuel cell application is fuel storage. The fuel supply should also be easily inserted into the fuel cell or the electronic device that the fuel cell powers. Additionally, the fuel supply should also be easily replaceable or refillable.
U.S. patent publication No. 2003/0082427 discloses a fuel cartridge where sodium borohydride fuel is reformed within the cartridge to form hydrogen and byproduct. However, the prior art does not disclose a fuel supply that allows in situ production of fuel or that contains reagents amenable to non-corrosive, low cost storage, or fuel supplies with the advantages and features described below.
Typically, the MEA is located inside a fuel cell which is located inside consumer electronic devices. U.S. published patent application Nos. 2003/0082416 and 2003/0082426 disclose such devices. In such devices, the fuel supply is removable and stored in a cartridge. The life of the MEA is usually limited by the life of the PEM. The PEM efficiency is susceptible to various factors such as fuel flow rate, metal ion concentration in the fuel, fuel temperature, and ambient/stack temperature. When the PEM efficiency is at a sufficiently low level, the PEM has to be replaced or refurbished. Frequent servicing of the PEM is undesirable as it requires servicing the electronic device.
A need exists for a fuel cell system that allows servicing or repairing the PEM without servicing the electronic device.

Cartridge with fuel supply and membrane electrode assembly stack


Systems and methods for user control of vehicular transmission shift points. In one embodiment, a user may control a transmission shift point by adjusting a selector having non-discrete selectable positions. Such selector may generate a signal indicative of its position to a transmission controller. The transmission controller may receive the signal from the selector and determine at least one transmission shift point based upon the selector position. The transmission controller may thereby control the transmission to effectuate a gear change when the shift point is achieved. In some embodiments, the selector may comprise a rotary potentiometer, a rotary encoder, an inline potentiometer, an inline encoder or the like.

Generally, transmission control systems may be provided in a vehicle to effectuate transmission gear change (i.e., upshift or downshift) at particular intervals called shift points. These shift points may be selected by monitoring various vehicle conditions (i.e., acceleration, road grade, accelerator depression, speed, etc.) and calculating a shift point to minimize transmission gear "hunting", overrunning or misshifting. A user may, however, select or adjust the shift points to dynamically personalize vehicle performance. Typically, a user may control a shift point by adjusting a selector. In one such system, the selector may provide selection of shift points from a finite set of shift points (i.e., a discrete selector). However, such systems are inflexible and limited in the programmability they can provide. In another such system, the selector may only provide instantaneous selection of a shift point (i.e., shifting immediately when a shifting mechanism is engaged). However, such systems do not allow for setting or programming shift points. Accordingly, there is a need for systems and methods that have greater flexibility and allow for more user control. There is also a need for systems and methods that provide user-selectable shift points without a need for continual user interaction.

Toyota Motor Engineering & Manufacturing North America, Inc.


The present method induces an oxidation-proof ferric phosphate coating on iron sulfide such as pyrite and marcasite. The method includes the steps of placing the pyrite to be treated in a reaction vessel and leaching the pyrite with a coating composition including water, an oxidizing agent and a phosphate coating agent. Examples of oxidizing agents include hydrogen peroxide, sodium hypochlorite, potassium hypochlorite and mixtures thereof. The phosphate coating agent may be potassium dihydrogen phosphate. In order to ensure the formation of the stable coating, the leaching is performed at a pH of substantially 5 and at a temperature of substantially 40.degree. C. Additionally, the oxidizing agent is maintained at a concentration of substantially 0.1% by weight of the coating composition while the concentration of the phosphate coating agent is maintained at at least substantially 10.sup.-4 M/l.

In recent years, the public, industry and government at all levels have become acutely aware of the need to manage the nation's water resources more efficiently. Further, society is now demanding that cleaner streams, rivers and lakes be provided free from pollutants that might interfere with the best use of these resources. Accordingly, many new laws have been passed that prohibit the discharge of water into streams unless or until it is free from certain pollutants. As a result mine water or mine drainage is one of the more serious environmental problems facing the coal industry today. This is particularly true as it relates to long established underground operations (Crickmer, Douglas F., Zegeer, David A., Elements of Practical Coal Mining, The Society of Mining Engineers of the American Institute of Mining, Metallurgical and Petroleum Engineers, Inc., New York, N.Y., 1981, pp. 669-672).
More specifically, mining operations for coal and various ores involve the in situ exposure of pyrite and marcasite containing geologic strata to the atmosphere. These iron sulfide compounds undergo oxidation upon contact with the oxygen and water that is plentiful in the environment. This oxidation produces highly acid water enriched with various heavy metals.
In addition to pyrite and marcasite present in the geologic strata, pyrite and marcasite is often a component of the mined ore product. Upon further treatment of the ore for product purification purposes this additional pyrite and marcasite is separated and treated as a waste product. This waste product is subject to oxidation as described above and consequently also produces acid solutions enriched with heavy metals. As already indicated, both the acid solutions and heavy metals are now recognized as very significant environmental pollutants that must be controlled. Up until the development of the present invention, however, there has been no reliable, long term, economic technique to reduce or prevent the oxidation of the pyrite and marcasite.
To date, there have been three approaches utilized to treat pyrite/marcasite rich material in order to control oxidation. In the first approach, neutralizing agents are utilized to treat acid drainages produced from the oxidation. Unfortunately, this approach only treats the symptoms of the oxidation and simply does not address the cause. Further, the approach is very costly. Additionally, it only represents a short term solution as it is not feasible to periodically return to the site to retreat the drainages over an extended period of time.
The second approach involves the utilization of detergents to kill sulfur oxidizing bacteria. Unfortunately, this approach is also only a relatively short term solution lasting from six months to a year. Further, it is also only suited to certain field conditions and thus has limited applications. Still further, utilization of some of the detergents also effects the environment adversely and accordingly, the impact of this procedure must be closely monitored.
The third and final approach commonly utilized is physical encapsulation of the pyrite/marcasite containing waste products. More particularly, clay liners, plastic liners and blacktop liners may be utilized to prevent oxygen and water from reaching the pyrite and marcasite. Unfortunately, this approach is very expensive. Additionally, the liners are subject to cracking and the cost to repair cracked liners is prohibitive. Accordingly, this approach is rarely used by mine operators.
A fourth approach is proposed in Flynn U.S. Pat. No. 3,443,882. In this patent earth strata; rocks, mine tailings, gob piles and the like are treated to prevent oxidation of iron sulfide compounds such as pyrite and marcasite. More specifically, Flynn teaches the application of a phosphate coating on the pyrite and marcasite by mixing the materials with an inorganic phosphate such as naturally occurring calcium phosphate. This phosphate is disclosed as gradually converting the iron sulfide (FeS.sub.2) to calcium sulfate (CaSO.sub.4), and vivianite (Fe.sub.3 (PO.sub.4).sub.2).
Experiments have, however, unfortunately shown that if one applies calcium phosphate to pyrite/marcasite in nature, the calcium phosphate actually becomes coated through a well-known reaction called metal surface adsorption. More specifically, as the pyrite and marcasite are oxidized through contact with oxygen and water, ferrous sulfate (FeSO.sub.4) is generated. This is a very soluble salt that rapidly coats the pulverized calcium phosphate rendering it inactive. Accordingly, it has been found that the metal surface adsorption not only prevents the production of vivianite as suggested by Flynn but it also makes the Flynn approach inoperative.
In an effort to avoid the coating of the phosphate itself, Flynn recommends in the patent the application of sulfuric acid. However, it should be appreciated that sulfuric acid causes very significant damage to ground water supplies by dissolving more heavy metals. Accordingly, this proposed solution to the problem is simply environmentally unacceptable. Additionally, the Flynn patent suggests the utilization of chlorine or bromine gas to kill the sulfur oxidizing bacteria. At best, such a procedure would only be effective for a few months before additional treatments would be required. Furthermore, it is unlikely that the utilization of such highly toxic gasses as chlorine or bromine would ever be approved by the government. As a result of these and other shortcomings, the approach proposed by Flynn has not been put into practice.
Following review of this background to the pyrite and marcasite oxidation problem, it should be appreciated that a need exists for a better solution. Further, the need is great. So as to have a better understanding of the extent of the problem, an average coal processing plant produces anywhere from 1 to 5 tons of finely ground pyrite per hour. Thus, this is a very significant environmental problem.

H.sub.2 O.sub.2 induced oxidation proof phosphate surface coating on iron sulfides

University of Kentucky Research Foundation


A method of processing a semiconductor wafer is provided. The method includes installing upper lid. The installation of the upper lid includes placing an inlet manifold on a water box; inserting a jig into a lower gas channel in the water box and inserting into an upper gas channel in the inlet manifold; fastening the water box to the inlet manifold; and removing the jig after the water box engaging with the inlet manifold. The method also includes connecting a shower head on a lower side of the water box; and connecting the upper lid to a housing. The method further includes placing a semiconductor wafer into the housing. In addition, the method includes supplying a process gas over the semiconductor wafer through the upper gas channel, the lower gas channel and the shower head.

The semiconductor integrated circuit (IC) industry has experienced exponential growth. Technological advances in IC materials and design have produced generations of ICs where each generation has smaller and more complex circuits than the previous generation. In the course of IC evolution, functional density (i.e., the number of interconnected devices per chip area) has generally increased while geometric size (i.e., the smallest component (or line) that can be created using a fabrication process) has decreased. This scaling-down process generally provides benefits by increasing production efficiency and lowering associated costs. Such scaling-down has also increased the complexity of processing and manufacturing ICs.
One broad category of commonly used techniques employed to form material layers and alter properties over semiconductor wafers is deposition, which includes the techniques such as chemical vapor deposition, physical vapor deposition, sputtering, ion implantation, etc. Although existing fabrication tool and methods for producing or depositing material layers on the semiconductor wafer have been generally adequate for their intended purposes, they have not been entirely satisfactory in all respects.

Semiconductor fabrication tool having gas manifold assembled by jig

TAIWAN SEMICONDUCTOR MANUFACTURING CO., LTD.


An improved electrodeionization apparatus and method are provided. The electrodeionization apparatus includes an ion-concentrating compartment, an ion-depleting compartment, and electrolyte compartments, wherein alternating layers of anion exchange resins and cation exchange resins are positioned in the ion-depleting compartment, and the anion exchange resins comprise Type II anion resins. The incorporation of Type II anion material, alone or with Type I anion material, in anion permeable membranes and/or resins improves the electric current distribution, degree of resin regeneration, and deionization performance.

1. Field of the Invention:
The present invention relates to an electrodeionization apparatus and method and, more particularly, to an electrodeionization apparatus and method incorporating membrane and electroactive media combinations, including Type II anion material, solely or in combination with Type I anion material, to improve electric current distribution, degree of resin regeneration, and deionization performance.
2. Description of the Related Art:
Electrodeionization (EDI) is a process that removes ionizable species from liquids using electrically active media and an electrical potential to influence ion transport. The electrically active media may function to alternately collect and discharge ionizable species, or to facilitate the transport of ions continuously by ionic or electronic substitution mechanisms. EDI devices may comprise media of permanent or temporary charge, and may be operated batchwise, intermittently, or continuously. EDI devices may be operated to cause electrochemical reactions specifically designed to achieve or enhance performance, and may comprise electrically active membranes such as semipermeable ion exchange or bipolar membranes.
In continuous electrodeionization (CEDI), which includes processes such as continuous deionization, filled cell electrodialysis, or electrodiaresis (EDR), the ionic transport properties of the electrically active media are the primary sizing parameter. These processes are described, for example, by Kollsman in U.S. Pat. No. 2,815,320; Pearson in U.S. Pat. No. 2,794,777; Kressman in U.S. Pat. No. 2,923,674; Parsi U.S. Pat. Nos. 3,149,061 and 3,291,713; Korngold et al. in U.S. Pat. No. 3,686,089; Davis in U.S. Pat. No. 4,032,452; U.S. Pat. No. 3,869,376; O'Hare in U.S. Pat. No. 4,465,573; Kunz in U.S. Pat. Nos. 4,636,296 and 4,687,561; and Giuffrida et al. in U.S. Pat. No. 4,632,745.
A typical CEDI device comprises alternating electroactive semipermeable, anion and cation ion-exchange membranes. The spaces between the membranes are configured to create liquid flow compartments with inlets and outlets. A transverse DC electrical field is imposed by an external power source using electrodes at the bounds of the membranes and compartments. Often, electrolyte compartments are provided so that reaction products from the electrodes can be separated from the other flow compartments. Upon imposition of the electric field, ions in the liquid are attracted to their respective counterelectrodes. The compartments bounded by the electroactive anion membrane facing the anode and the electroactive cation membrane facing the cathode become ionically depleted, and the compartments bounded by the electroactive anion membrane facing the cathode and the electroactive cation membrane facing the anode become ionically concentrated. The volume within the ion-depleting compartments, and preferentially within the ion-concentrating compartments, is also comprised of electrically active media. In continuous deionization devices, the media may comprise intimately mixed anion and cation exchange resins. The ion-exchange media enhances the transport of ions within the compartments and can also participate as a substrate for controlled electrochemical reactions. The configuration is similar in EDR devices, except that the media comprise separate, and sometimes alternating, layers of ion-exchange resin. In these devices, each layer is substantially comprised of resins of the same polarity (either anion or cation resin) and the liquid to be deionized flows sequentially through the layers.
A number of CEDI devices and processes have been successfully commercialized, for example, as disclosed by Giuffrida in U.S. Pat. No. 4,298,442; Giuffrida et al. in U.S. Pat. No. 4,632,745; Siu et al. in U.S. Pat. No. 4,747,929; Palmer in U.S. Pat. No. 4,804,451; Giuffrida et al. in U.S. Pat. No. 4,925,541; Giuffrida U.S. Pat. Nos. 4,931,160 and 4,956,071; White in U.S. Pat. No. 5,116,509; Oren et al. in U.S. Pat. No. 5,154,809; Giuffrida et al. in U.S. Pat. No. 5,211,823; and Ganzi et al. in U.S. Pat. Nos. 5,308,466 and 5,316,637. In addition, there have been a wide range of devices described in the literature, including Walters et al., "Concentration of Radioactive Aqueous Wastes," Ind. Eng. Chem., Vol. 47, 1, pp. 61-67 (1955); Sammon et al., "An Experimental Study of Electrodeionization and Its Application to the Treatment of Radioactive Wastes," AERE-R3137, Chemistry Division, U.K. AEA Research Group, Atomic Energy Research Establishment, Harwell (June 1960); Glueckauf, "Electrodeionization Through a Packed Bed," British Chemical Engineering, pp. 646-651 (December, 1959); Matejka, "Continuous Production of High Purity Water by Electrodeionization," J. Appl. Chem. Biotechnol., Vol. 21, pp. 117-120 (April, 1971); Shaposhnik et al., "Demineralization of Water by Electrodialysis with Ion-Exchanger Packing Between the Membranes," Zhurnal Prikladnoi Khimii, Vol. 46, 12, pp. 2659-2663 (December, 1973); Korngold, "Electrodialysis Processes Using Ion Exchange Resins Between Membranes," Desalination, Vol. 16, No. 2, pp. 225-233 (1975); and Kedem et al., "Reduction of Polarization by Ion-Conduction Spacers," Desalination, Vol. 27, pp. 143-156 (1978).
There remains a need for devices and processes with improved reliability and the ability to operate under more rigorous conditions with reduced power consumption and reduced membrane area. Often, the limiting factor in the applicability of CEDI is the ability of the electroactive media within the device to withstand the temperature, chemical, and fouling conditions of the liquid to be processed. One difficulty in specifying such electroactive media results from the need in most applications to incorporate both anion and cation media within the compartments and the membranes. Many times, conditions are relatively benign for media of a given fixed charge, but are limited by the oppositely charged media. For example, the presence of iron in the liquid to be processed may result in fouling of cation exchange resin and membrane, but would not affect the performance of anion exchange resin or membrane. Conversely, the presence of high temperature, chlorine or intermediate molecular weight weak organic compounds may result in degradation, oxidation, or fouling of anion exchange resin and membrane, but would not affect the performance of cation exchange resin or membrane.
Performance of CEDI may further be limited by difficulty in obtaining the desired electrical current distribution with the device. Electroactive media of permanent charge may change their electrical resistance properties in undesired ways depending on their ionic form. For example, in the ion substitution of sodium with hydrogen ion in EDR, most cation exchange resin will preferentially transport hydrogen ion over the desired transport of sodium ion. This results in electrical inefficiencies and, under certain circumstances, may cause pH shifts that are detrimental to valuable products within the liquid. In another example, a given electroactive media may be desirable for transport properties, such as the Type II anion membrane and resins for continuous deionization and EDR, but may have the undesirable properties of catalyzing the ionization reaction of water to hydrogen and hydroxide ions.
Furthermore, the presence of gases, poor flow distribution, low temperature and/or low conductance liquids within the electrolyte compartments may be detrimental to electrical current distribution, thereby reducing the efficiency of deionization. However, as a result of the oxidizing or reducing conditions common within the electrolyte compartments, standard electroactive media such as ion exchange resins or activated carbons (e.g. carbons prepared by pyrolyzing coal into small imperfect granulars having an interfacial area on the order of 10 m.sup.2 /g and contain up to 20% ash impurities) cannot be incorporated within the electrolyte compartments because of their limited chemical resistance.
In electrochemical ion exchange (EIX) and capacitive deionization (CapDI), both the transport and the capacity of the electroactive media are important sizing parameters. In EIX, the electrode reactions produce ions that are used for ionic substitution reactions within the electroactive media. Typical EIX devices, as described, for example, by Hobro et al. in "Recycling of Chromium from Metal Finishing Waste Waters Using Electrochemical Ion Exchange," Electrochemical Society, Symposium on Water Purification, PV94-19, pp. 173-183 (1994), may or may not comprise ion exchange membranes. Similar to the CEDI processes, the performance of the EIX devices are often limited by use of permanently charged media, media of limited temperature and/or chemical resistance, and/or media with undesirable ion transport properties. In CapDI, high surface area, usually carbon type electrodes are used to adsorb ions as polarity is imposed, and then desorb ions as the electric field is removed or reversed. As with other processes, typical CapDI devices may also be limited by the use of electrodes of low chemical resistance, or limitations of the media to act equally well or in the desired manner when in use as both a cation and anion adsorber or as both an ion adsorber and desorber.
Therefore, a need remains for an improved electrodeionization apparatus having improved electric current distribution, degree of resin regeneration, and deionization performance. Moreover, there is a need for an electrodeionization apparatus which promotes or limits electrochemical water dissociation depending on its chemical environment. Lastly, there is a need to provide improved methods of operation of an electrodeionization apparatus.

Electrodeionization apparatus and method


The present invention includes a ferro fuse cell comprising a ferroelectric storage capacitor electrically connected to a plate on one side and to a sense amplifier on the other side. A ferroelectric measurement capacitor is electrically connected between the ferroelectric storage capacitor and the sense amplifier.

Electrical fuses are used to store address information for redundancy repair of high-density memories or other set-up information in memory or logic circuit components. In contrast to conventional laser fuses, electrical fuses can be set and reset even in packaged components. Such electrical fuses can be implemented with non-volatile memory cells using ferroelectric capacitors. Read out of such a ferroelectric capacitor memory cell typically requires a certain optimized "measurement" capacitance. In memory circuits, the parasitic bit-line capacitance is used for this purpose. In ferro fuse circuits, typically only one single cell is connected to the sense amplifier, i.e. no bit line or only a very short bit-line exists. Therefore, the bit-line capacitance is replaced by a gate oxide capacitance.
FIG. 1 shows a ferro fuse circuit 101 of the prior art. A ferroelectric capacitor (C1) 103 is connected to a plate (PL) 105 on one side and to a measurement capacitor (C2) 107 on the other side. By pulsing the plate (PL) 105, a read signal develops on a node F 109 depending on the stored polarization state in the capacitor C1103. If a "1" was stored in the ferroelectric capacitor C1103 then a bigger voltage is obtained on the node F 109 (switching). If a "0" was stored then a smaller voltage is obtained on the node F 109 (non-switching). These two voltage levels are compared to a reference voltage VREF 111 by a differential sense amplifier (SA) 113 and the fuse data is available on a node FD 115. As the read operation is destructive, a write back is required, which is performed automatically by the sense amplifier 113.
FIG. 2 shows another prior art ferro fuse circuit 201. The circuit 201 uses two cells like the cell 101 in FIG. 1 are combined to store one single data bit. Two ferroelectric capacitors C1203 and C3204 are connected to a plate (PL) 205 on one side and to measurement capacitors C2207 and C4208 on the other. The two ferroelectric capacitors C1203 and C3204 always contain reversed data (i.e. if a "1" signal is obtained on a node F 209 then a "0" signal is obtained on a node /F 210, and visa versa). Thus the differential signal between the nodes F 209 and /F 210 is doubled compared to the implementation of FIG. 1. Fuse data output from a sense amplifier 213 is available on a node FD 215. Furthermore, no reference voltage is required. However, in the implementation of FIG. 2, the area for storage and measurement capacitors is doubled.
It would be desirable to produce a ferro fuse having a large signal margin.


A digital neural network has a plurality of neurons (NR) completely meshed with one another, each of which comprises an evaluation stage having a plurality of evaluators (B) that is equal in number to the plurality of neurons (NR) and each of which comprises a decision stage having a decision unit (E). An adjustment information (INF.sub.E) that effects a defined pre-adjustment of the decision unit (E) can be supplied to every decision unit (E) by a pre-processing means via an information input. A weighting information (INF.sub.G) can be supplied to every evaluator (B) by a pre-processing means via an individual information input. An output information (INF.sub.A) can be output by every decision unit (E) to a post-processing means via a respective individual information output. The information outputs of the decision units (E) are each connected to an individual processing input of all evaluators (B) allocated to the appertaining decision unit (E). Individual processing outputs of the evaluators (B) are connected to individual processing inputs of the decision unit (E) in the appertaining neuron (N), so that every output information (INF.sub.A) can be indirectly fed back onto every neuron (NR).

The present invention is directed to digital neural networks executed in integrated circuit technology.
Artificial neural networks (referred to below as ANN) are proposed for the parallel processing of extremely large data sets with the goal of pattern recognition and processing (for example, of speech or images). Known ANN of this species are composed of a plurality of non-linear processor elements (neurons) that are networked with one another via variable "weighting factors".
The following non-linear transfer characteristics have been proposed for modeling the neurons, c.f. R. P. Lippmann, "An Introduction to Computing with Neural Nets", IEEE ASSP Magazine, Apr. 1987, pages 4-22:
binary decision, PA1 linear ramp function with saturation characteristic, PA1 sigmoidal function, PA1 tangent-hyperbola function.
Further, a plurality of different structures for the networking of the neurons exist (for example "Hopfield net", "Hamming net", "Perceptron", c.f. R. P. Lippmann as well). A direct digital realization of large nets of this type seems impossible with the current technologies for manufacturing integrated circuits because of the plurality of neurons (>1000) that are required. The main problem is thereby that the number of connections and, thus, the number of variable weighting factors quadratically increases with the number of neurons. For example, 1,000,000 weights are required given 1000 neurons in a completely meshed network.
A few realizations of ANN having, for example, 54 or 256 neurons are disclosed in the literature for a programmable or non-programmable network, respectively, c.f. H. P. Graf, P. De Vegvar, "A CMOS Associative Memory Chip based on Neural Networks, Proc. 1987 IEEE Int. Conf. on Solid State Circuits, pages 304, 305, 437; H.P. Graf et al, "VLSI implementation of a neural network memory with several hundreds of neurons", AIP Conference Proceedings 151, "Neural Networks for Computing", pages 182 through 187, Snowbird, Utah, 1986; W. Hubbard et al, "Electronic Neural Networks", AIP Conference Proceedings 151, "Neural Networks for Computing", pages 227 through 234, Snowbird, Utah, 1986. Proposed realizations have also been disclosed in J. P. Sage, K. Thompson, R. S. Withers, "An Artificial Neural Network Integrated Circuit based on MNOS/CCD principles", AIP Conference Proceedings 151, "Neural Networks for Computing", pages 381 through 384, Snowbird, Utah, 1986. These all involve analog realizations of analog ANNs. Compared to digital realizations, they have the advantage of a significantly smaller implementation surface area. What is disadvantageous, however, is the high power consumption caused by the required resistance matrix, this power consumption opposing a realization of larger, programmable networks (with more than a few hundred neurons). The behavior and the properties of the modelings of ANNs hitherto proposed are preeminently investigated by simulation on vector computers, work stations or special processor fields. The fundamental disadvantage of this method is that the (space) parallelism inherent in the neural network is completely or partially lost in the processing of the information and, thus, the calculating time of the simulated network increases to such orders of magnitude, particularly for large neuron composites, that a speedy or quasi-real-time processing of the jobs cited above is impeded or becomes impossible.
A significant shortening of the calculating time and a far greater pattern throughput is obtained, by contrast, with hardware emulators. In contrast to hardware simulators, they contain an artificial neural network having a small size with whose assistance a larger network can be emulated.
In addition to a higher throughput, the advantage of a digital realization of an ANN is comprised in the greater freedom with which the user can select and set network-typical parameters (for example, discriminator functions).
The demands that users currently make of the degree of complexity (>1000) for general neural networks currently exceed the possibilities of present VLSI integration technology.
In addition to these general, relatively large and complex neural networks, special solutions for specific jobs having smaller neural networks have already been proposed. These proposed, smaller networks are usually realized as complete solutions on a chip, being realized in analog technology with the disadvantages connected therewith.

Digital neural network executed in integrated circuit technology


The invention provides a testing system and method suitable for determining whether a pin-out of an electrical component is properly connected to a PCB. The testing system includes a testing signal source, a signal detector, a signal processor, an analysis unit and an integrated circuit having boundary-scan test function to provide testing signals to the device under test (DUT) whose signal traces are passing through inner layer of PCB in order to detect whether the sensed signal is an error signal.

The testing procedure of print circuit board assembly (PCBA), an important step in the front-end processes is examining whether the pins on integrated circuits (ICs), connectors and other electronic devices are properly connected to the printed circuit board. Such test not only can increase product quality, it can also detect manufacturing defects in the front-end processes. Today, the "automatic optical inspection" method (AOI) has replaced the conventional manual inspections. The AOI method not only reduces cost and eliminates human errors, but it also increases the speed of inspection. However, AOI method can not be used to examine the pins, for example pins covered by the device itself such as in a "ball grid array" (BGA) packaged device. Such problem can be resolved by using an "automatic X-ray inspection" (AXI); however the cost for such inspection is high. The "in circuit tester" (ICT) provides another testing method. Under ICT, though it is required to fit different fixtures for different DUT, the probes on the fixture are capable of examining all the ICs on the printed circuit board assembly. Moreover, the fast testing speed, the accuracy of locating the defects, and a test coverage rate higher than both automatic optical inspection and automatic X-ray inspection, are all noted advantages of ICT.
A general ICT is equipped with a "manufacture defect analyzer" (MDA) to detect defects such as device damage, short, false welding and misplacement. However, MDA is only favorable for analog devices. A complete inspection of the digital circuits can be carried out by combining a "boundary-scan test" technique.
The Boundary-scan test is also known as JTAG test or IEEE1149.1. Such technique was proposed to IEEE committee by Join Test Action Group (JTAG) in 1988, and the standard of "Standard Test Access Port and Boundary-Scan Architecture" (IEEE std. 1149.1-1900) was established in 1990.
Connecting probes on the fixture to the testing point of DUT is the first step of conventional testing method. Once the probes are connected, the ICT generates signals to examine each DUT through the testing point. However, the complexity of printed circuit board assembly has increased significantly today, for example the number of pins is increased while the distance between the pins is decreased in devices such as CPU, ASIC, Chipset, etc. Such complexity change reduces the number of possible testing points. Boundary scan test provides a solution to the above mentioned problems. Today, circuits with boundary-scan function are commonly built in ICs for inspection purposes. Boundary-scan method scans through all the input and output pins of the integrated circuit devices in order to obtain the testing data of the said pins, or to examine whether the ICs and the printed circuit board are properly connected.
Referring to FIG. 1, it shows a block diagram of a conventional testing system arrangement, which includes an integrated circuit A (IC A) 10 and an integrated circuit B (IC B) 20, each contains a circuit with boundary-scan test function. Such a chip comprises four basic elements: Test Access Port (TAP) 30, TAP controller 40, Instruction Register (IR) and Data Register (DR), wherein only the TAP, TAP controller, IR, and some of the DRs are essential elements for operation. The required DRs are Boundary Scan Registers 50 and Bypass registers, while the other registers are optional. Next to the internal core-circuit, Boundary Scan Cells (BSCs) 55 are located between the internal core-circuit and the pins of ICs. BSCs serve as the probes inside the ICs; and serially connected BSCs form the Boundary Scan Register. During a test, at least four boundary-scan pins in TAP are used to control and convey the testing data through the TAP controller in IC. The four pins are: Test Data Output (TDO), Test Data Input (TDI), Test Clock (TCK), and Test Mode Select (TMS). A fifth pin, Test Reset (TRST), is optional. By inputting serial data to the TDI pin of IC A, which acts to send the test data to the BSCs, the test data can be shifted between BSCs. The test data can then be serially transferred from the TDO pin of IC A to the TDI pin of IC B, following a data shifting test in the BSCs of IC B. The shifted data can be observed at the TDO of IC B; a scan chain is herein completed. While the test data shifts to the output pin of BSCs in IC A, the internal connection within the chip and the interconnection between the chips of IC A and IC B carry out a parallel output to transfer the test data in BSCs to the bonding wires of a printed circuit board through the output pins. Meanwhile the test data is transferred to the input pins of IC B. Next, the BSCs of IC B first obtain the test data on the input pins by a parallel input and shift the data. Subsequently, the test data on output pins of IC B is compared to the test data on input pins of IC A; if the test data are the same, the connection between IC A and IC B, and the connections between some pins of IC A and some pins of IC B to the printed circuit B, are proper. On the contrary, the number of times data shifted indicates the number of improper connections between a pin of IC A and IC B. The boundary-scan test for a single IC can also be accomplished by alternating the serial and the parallel testing.
Boundary-scan test is capable of examining the internal function of IC and the pins connected to the printed circuit board. Boundary-scan test is a technique designed to overcome the difficulties in testing due to the improvement of IC manufacturing process. Except for reducing the number of probes on the fixture, tiny pins can also be examined easily by such a technique.
In order to examine the connection between the printed circuit board and the IC or the connector, Capacitive Coupling Test can be adopted as a convenient, reliable, and vector-less technique. Moreover, Capacitive Coupling Test does not damage the DUT since there is no destruction of DUT. Such method of examination uses an equivalent capacitance between the lead frame of IC and the extra sensor plate to establish a weak connection between the lead frame of IC and the extra sensor plate. The intensity of the coupled signals suggests the connecting condition between the electronic devices. By applying small AC signals to the testing pin of IC, the signals will couple to the sensor plate through the capacitance generated by the interface above and provide a reference voltage A if the printed circuit board is properly connected to the IC or the connector. On the contrary, if the printed circuit board is not properly connected to the IC, the value of capacitance at the interface will decrease and the signals cannot be coupled to the sensor plate easily, meanwhile a reference voltage B is provided. Whether an IC is properly connected to the printed circuit board can be determined by the difference of the small AC signals. Such a technique was first disclosed by Agilent Technologies in U.S. Pat. No. 5,254,953 in 1993, and it is now broadly adopted in the relevant industries.
As the manufacturing process for semiconductor improves, the printed circuit board assembly, for example the ball grid array (BGA) packaging, increases the density but lowers the volume of ICs at the same time, making it more difficult to reserve testing points on the DUT. The improvement of IC printed circuit board assembly suggests a significant growth in wire-density and a significant compression on board-space. Therefore, High Density Interconnect (HDI) technology is introduced to the manufacturing process of print circuit board to provide advantages of small size. By employing HDI technology, ICs or the connectors may be connected to the printed circuit board through its inner layers. As a result, the connections cannot be tested through the outside testing points as described above. Because the small AC signal cannot be delivered to the testing points of IC through outside probes, the inspection of the connectors that connect to the printed circuit board through its inner layers, such as PCI-E, DDR ⅔, CPU socket, becomes a great challenge.
Although other efforts have been developed in the probe-testing on the surface of high density printed circuit board, a proper testing method of delivering signals through the inner layer of printed circuit board to the DUT has not been achieved.
As a result, it is necessary to introduce a new technique to complement all the insufficiencies of prior arts. A testing system and method that overcomes the obstacles of signal delivery is required to increase the coverage of inspection and eliminate the blind spots of examination.

Electronic device testing system and method


A confocal fluorescence microscope of the present invention consists of: a light source unit broadly comprising one or more short wavelength laser beams; a lens unit which converts parallel light, emitted from a light source, into linear light having an appropriate size; a multi-color mirror which reflects the light source and enables fluorescence to transmit so as to separate the light source and the fluorescence; a scan mirror which radiates the light source over a wide area and scatters the fluorescence over a large-area camera; a microscope unit which radiates the incident light source to a target object, collects the fluorescence emitted from the target, and outputs the collected fluorescence; and a detecting unit which removes the background of the outputted fluorescent signal and observes the outputted fluorescent signal.

Confocal fluorescence microscopy is a technology that is capable of obtaining an improved image by removing background signals emitted from parts other than the focal plane of a microscope lens using a pinhole or the like, compared to conventional fluorescence microscopy. For this reason, confocal fluorescence microscopy technology is widely used in biological research.
A common confocal fluorescence microscopy technology requires scanning in two axial directions in order to obtain one image because light is focused in a dot form in order to observe fluorescent light. Accordingly, the common confocal fluorescence microscopy technology is disadvantageous in that it takes an excessively long time to obtain one image and it is difficult to observe the rapid movements of biological molecules and interactions therebetween within a cell.
A method devised to overcome the above disadvantages is line scan confocal microscopy or spinning disk confocal microscopy. In line scan confocal microscopy, light is focused in a line form, rather than in a dot form, using a cylindrical lens. As a result, the time it takes to obtain an image can be significantly reduced because scanning only in a single axial direction is required to obtain an image. In spinning disk confocal microscopy, an image can be rapidly obtained in such a way as to divide light into several parts, form several dot-shaped focuses at the same time, bore a hole through a disk, and rotate the disk. These two methods can obtain images at a speed (of several tens of Hz) close to a real-time speed.
Recently, with the advancement of related technology, the fluorescence microscopy technology has been advanced to the extent that a single fluorescent molecule can be observed. As a single fluorescent molecule can be observed, the various phenomena of life that were difficult to observe have become understood, and thus the fluorescence microscopy technology is being widely used. A single fluorescent molecule can be observed only when background signals are maximally reduced because the single fluorescent molecule has a very weak fluorescent signal. For this purpose, a total internal reflection method is widely used. When total reflection is generated between a slide and a medium, an evanescent wave is generated, which excites a fluorescent light substance. In this case, background signals generated from parts other than a part where total reflection is generated can be reduced because the range of the evanescent wave is very short, that is, about 200 to 300 nm from a surface where total reflection was generated. However, phenomena occurring inside a cell cannot be observed using the total internal reflection method because only fluorescent light in a very short range near a surface of the cell can be observed using the total internal reflection method.
The confocal microscopy method can be used to measure fluorescent light at a deep location inside a cell and the signal of a single fluorescent molecule, unlike the total reflection microscopy method. However, a common confocal microscope may not be used to observe a rapid change within a cell because the time it takes to obtain an image is long, as described above. In particular, because of its low speed, it is difficult to apply the common confocal microscope to recent ultra-high definition imaging technology based on the determination of the location of a single fluorescent molecule. In the case of line scan confocal microscopy and spinning disk confocal microscopy used to overcome measurement speed issues, the degree to which background noise is reduced is lower than when using a dot-shaped confocal method, and a detector used for observation has low performance. Accordingly, a single fluorescent molecular signal cannot be observed using currently commercialized equipment.
As a result, in order to observe a single molecule fluorescent light in a thick object, such as a cell or a tissue, there is a need for 1) an ability to observe fluorescent light at a deep location, 2) a rapid measurement speed of several tens of Hz or higher, and 3) a high signal-to-noise ratio and high-performance detector for observing single molecule fluorescent light.


The soft-start circuit includes a first charging transistor, a first capacitor, a second charging transistor, a second capacitor and a clamping p-type transistor. The first charging transistor is conducted in response to activating pulses to charge the first capacitor through a first output node such that a first output voltage at the first output node gradually increases. The second charging transistor is conducted in response to the first output voltage to charge the second capacitor through a second output node such that a second output voltage at the second output node gradually increases. The clamping p-type transistor includes a source terminal electrically connected to a clamping node, a drain terminal connected to a ground terminal and a gate electrically connected to the second output node, and is conducted when a voltage at the clamping node exceeds a clamping threshold value to pull low the voltage at the clamping node.

1. Field of Invention
The present invention relates to an electronic circuit. More particularly, the present invention relates to a power supplying circuit and a soft-start circuit of the same.
2. Description of Related Art
Power supply devices play an essential role in modern information technology. Among all the power supply devices, DC-DC switching regulators are very popular and are widely used for providing regulated DC power sources to electronic components.
However, during an activation period, a large inrush current may occur to increase the voltage at some nodes in the DC-DC switching regulators and thus damage devices.
Accordingly, what is needed is a power supplying circuit and a soft-start circuit of the same to address the issues mentioned above.

Power supplying circuit and soft-start circuit of the same


An exposure system and method that can optimize the exposure of an optical resist film independent of the chemical reaction of the resist film due to optical exposure. The optimum exposure time is measured using a first optical resist film and a first semiconductor wafer, and the data thus obtained is stored in a memory. Then, a second optical resist film on a second semiconductor wafer is exposed to the same exposing light, and the intensity of the reflected light for the second resist film and the second wafer at the start of exposing is measured. The stored data of the optimum exposure time for the first resist film and the first wafer is read out, and is used as the optimum exposure time for the second resist film and the second wafer.

1. Field of the Invention
The present invention relates to an exposure process and more particularly, to an exposure method and an exposure system that are effective for transferring patterns of geometrical shapes on an exposure mask to an optical resist film on a semiconductor wafer in semiconductor device fabrication.
2. Description of the Prior Art
In the exposure process of semiconductor device fabrication, recently, the patterns of geometrical shapes to be transferred have been miniaturized and at the same time, the wavelength of the exposing light has been decreased more and more. As a result, the multiple interference phenomenon of the exposing light has become unable to be ignored.
Specifically, since an optical resist film is formed on an underlying base material (typically, a semiconductor wafer or a conductive/insulating layer), the effective exposure energy of the film varies dependent upon the reflectance of the base material. Also, the effective exposure energy is affected by the optical absorption coefficient of the resist film. Accordingly, the exposure condition needs to be changed according to the combination of the resist film and the base material.
To cope with this need, conventionally, an exposure systems shown in FIG. 1 was developed, which was disclosed in the Japanese Non-Examined Patent Publication No. 4-148527 published in May 1992.
As shown in FIG. 1, this conventional exposure system is equipped with an optical detector 20 provided around a reduction projection lens system. Exposing light is illuminated through the lens system to an optical resist film formed on a semiconductor wafer, and is usually reflected by the wafer surface. The detector 20 detects the reflected light and outputs an electric signal to an integrating circuit 21.
The integrating circuit 21 serves to integrate the output signal during the exposure time, thereby obtaining the total optical energy of the reflected light.
On the other hand, the data of a preset exposure energy is input to a processor 22. The processor 22 converts the input data to the data of the optical energy.
A comparator 23 compares the data of the total optical energy of the actual reflected light sent by the integrating circuit 21 and the data of the optical energy sent by the processor 22. When both of the data accord with each other, the comparator 23 outputs a shutter closing signal to a shutter control circuit 24. The shutter control circuit 24 controls to close a shutter placed in the optical path of the exposure system, thereby stopping the exposure to the resist film.
When each exposure process starts, a start signal is input into the shutter control circuit 24. In response to the start signal, the circuit 24 outputs a reset signal to the integrating circuit 21. The operation of the circuit 21 is reset and restarts by the reset signal.
With the conventional exposure system shown in FIG. 1, the opening (i,e., exposing) time of the shutter can be controlled according to the base material having various reflectance values. Also, the shutter control is effective even when the resist film contains any dye and therefore has a reduced reflectance value.
Generally, the chemical reaction of an optical resist film due to optical exposure is affected by incident exposing light which is directly illuminated and reflected light which is reflected by an underlying base material. The exposed region of the resist film tends to become transparent due to a bleaching phenomenon, resulting in the increased transmittance and the increased intensity of the reflected light. Therefore, the intensity increase of the reflected light due to the optical exposure needs to be considered.
With the conventional exposure system shown in FIG. 1, however, the intensity increase of the reflected light is not considered during the integration process by the integrating circuit 21 and as a result, a problem that the exposure of the resist film is not always optimized occurs.
Further, the thickness of the optical resist film should be kept constant for all semiconductor wafers to be used. However, it is very difficult and consequently, some thickness fluctuation will take place. The thickness fluctuation of the resist film between the wafers causes to change the intensity of the reflected light.
Accordingly, with the conventional exposure system shown in FIG. 1, some error will occur in the exposure energy of the optical resist film. This error is also a cause of the above problem.


An electrostatographic recording apparatus includes an endless recording member upon which toner images are recorded. A densitometer is provided for measuring density of a toned area on the recording member. The densitometer includes a light emitting and/or light sensitive component that is located in an internal space confined by the endless recording member. The densitometer further includes a slidable support upon which the component is mounted in facing relationship with and proximate to an internal facing portion of the recording member. A stationary mounting structure is attached to a film core upon which the film-like recording member is supported. The slidable support is received within the stationary mounting structure. An electrical circuit is electrically connected to the component and is mounted on a side of the slidable support that is opposite in facing direction to that of the component.

As noted in U.S. application Ser. No. 08/970,832 filed in the names of Regelsberger et al, control of process conditions in an electrophotographic apparatus can be provided by forming toned density patches on the photoconductors. Such patches are formed by exposing, for example, interframe portions of the photoconductor to exposure light from the imaging source and developing same with the development station under appropriate electrical bias. By measuring the density of the patches, it can be determined whether adjustments are needed to one of the known operating process control parameters such as primary charger setpoint, exposure setpoint and development bias.
The density of the developed toned patches can be measured using a densitometer. One type, a transmission densitometer, projects light, visible or infrared, through an object onto a photodiode. The amount of energy reaching the photodiode determines the voltage output from the device.
In a copier/printer, the photoconductor passes between the light source and the photodiode. When the photodiode has toner on the surface, the amount of light reaching the photodiode is decreased. This changes the voltage output from the device, proportional to the optical density of the toner on the surface. Based on this voltage, the amount of toner applied to the photoconductor can be varied as required in order to obtain consistent image quality.
Another type of densitometer as described in U. S. Pat. No. 5,519,497 uses reflected flux rather than transmitted flux to determine density.
As these machines are used, contamination can build up on the surface of the photodiode, changing the voltage output. Typically, these devices are permanently fixed to the structure below the photoconductor, such that the photoconductor must be removed in order to clean the photodiode.
It is thus an object of this invention to provide a new and improved apparatus for locating the densitometer which eliminates the need to remove the photoconductor. This reduces the time required to perform maintenance on the machine, as well as reduces the risk of damage to the photoconductor. Other objects and advantages of the invention will become apparent from a reading of the specification taken in conjunction with the accompanying drawing.

Electrostatographic reproduction apparatus and method with improved densitometer


A method and system for in-vivo sensing includes transmitting data that relates to data stored in a memory area located in the sensing device. The data that relates to data stored in a memory area may be transmitted in a data block, and the data block may include sensory data. The data that relates to data stored in a memory area may be received, recorded, displayed, processed or used in any suitable way, for example, to generate commands to the sensing device.

In-vivo devices, such as, for example, capsules, may be capable of gathering information regarding a body lumen while inside the body lumen. Such information may be, for example, a stream of data or image frames from the body lumen and/or measurements of parameters that are medically useful, such as, for example, pH. A sensing device may transmit the gathered information via a hard-wired or wireless medium, and the gathered information may be received by a receiver/recorder. The recorded information may be sent from the receiver/recorder to a workstation to be analyzed and/or displayed.
Such a system may be operated by, for example, health care professionals and technicians, in a hospital, or another health facility.

System and method for transmitting the content of memory storage in an in-vivo sensing device


A web-spreading device and a web-spreading process are provided. The web-spreading device, is provided whereby a first web strand being conveyed and a second web strand being conveyed next to the first web strand in a web-processing machine can be offset in parallel to one another in order to set a spread. A frame supports a first deflecting device (5r; 5r′), which forms a first deflection axis for the first web strand (Br), and a second deflecting device (6r; 6r′), which forms a second deflection axis for the first web strand (Br), which deflection axis is the next deflection axis for the first deflection axis in the conveying direction (F). The first web strand (Br) is offset in parallel by wrapping around the deflecting device (5r, 6r; 5r′, 6r′) and the spread (X; X+Y) is thus set in its entirety or in part. At least one of the deflecting devices (5r, 6r; 5r′, 6r′) is mounted adjustably along an adjustment path in the frame (2) in order to set the spread (X; X+Y). The adjustment path is straight in its entirety or at least in one section and extends in the conveying direction (F) which the first web strand (Br) has between the deflecting device (5r, 6r; 5r′, 6r′).

DE 100 23 169 A1 describes a web-spreading device with two arrow-shaped turning bars, which are arranged one after another in the web conveying direction after a lengthwise cutting means and are mounted pivotably in relation to one another in a machine frame. Two web strands of a web cut lengthwise are conveyed next to one another through the web-spreading device and wrap around one half each of the arrow-shaped turning bars one after another, so that the web strands are offset in parallel and have a spread between them when they run off from the web-spreading device. By pivoting only one of the arrow-shaped turning bars or both turning bars in relation to one another, the lengths of the web strands between the arrow-shaped turning bars and the wrapping angles with which the web strands wrap around the arrow-shaped turning bars are changed and the spread is adjusted as a result. However, changes in the web tension are associated with the adjustment of the spread.

Web-spreading process and web-spreading device


The disclosed is a memory such DRAM (dynamic random access memory), particularly an X-address extractor, an X-address extraction method and a memory adaptable to a high speed operation. A DRAM receives X and Y-addresses through an address line. The X-address is input through a command line when an active command is input to the DRAM, and the Y-address is input when a read/write command is input to the DRAM. The X-address abstractor performs a function of extracting the X-address from the X and Y addresses transferred through the address line. A conventional X-address extractor has a problem that the X-address has a different value when a selection signal changes to logic ‘0’ from logic ‘1’ after an address signal changes to another value from an X-address. The present X-address extractor includes a selection signal generator, a delayer, a latch and an X-address switch, without the problem of the conventional art.

1. Field of the Invention
The present invention relates to a memory such as a DRAM (dynamic random access memory), and particularly to an X-address extractor and a memory adaptable to a high speed operation.
2. Discussion of Related Art
A DRAM receives an X-address and Y-address through an address line. The X-address is input through a command line when an active command is input to the DRAM, and the Y-address is input when a read/write command is input to the DRAM. The X-address extractor performs a function of extracting the X-address among the X and Y addresses transferred through the address line.
Hereinafter, a conventional X-address extractor will be described with reference to FIGS. 1 and 2.
FIG. 1 is a block diagram of an X-address abstractor according to a conventional art. In FIG. 1, the X-address extractor includes a selection signal generator 10 and an X-address switch 120.
The selection signal generator 110 inputs a command signal CMD and then outputs a selection signal SEL. The command signal CMD is output as the selection signal SEL at rising and falling edges of a clock signal CLK.
The X-address switch 120 receives an address signal ADD and the selection signal SEL and then outputs an X-address signal XADD. When the selection signal SEL is logic '1', the address signal ADD becomes the X-address signal XADD. When the selection signal SEL is logic '0', the address signal ADD retains its previous value.
By such an operation, the X-address extractor extracts the X-address signal XADD from the address signal ADD.
However, as illustrated in FIG. 2, the selection signal SEL is considerably delayed from the command signal CMD because it is operable in sync with the clock signal CLK. As the address signal ADD is transferred to the X-address signal XADD by the selection signal SEL, the X-address signal XADD is much delayed than the address signal ADD. Furthermore, the X-address signal XADD has a different value not the X-address when the selection signal SEL changes to logic '0' from logic '1' after the address signal ADD changes to another value from an X-address. Such a problem should be overcome for an improvement of a high speed DRAM because it would be more serious as the DRAM is improved in a higher speed.

X-address extractor and memory for high speed operation


An image forming apparatus is provided with a latent image carrier for holding an electrostatic latent image, and an intermediate transfer member for temporally holding an image formed by visualizing the electrostatic latent image formed on the latent image carrier. The image forming apparatus performs image formation by superimposing a plurality of images on the intermediate transfer member so as to form a superimposing image, and transferring the superimposing image on a recording medium. The intermediate transfer member has a latent image holding property for holding the electrostatic latent image. An image formed by visualizing an electrostatic latent image formed on the intermediate transfer member is superimposed with the electrostatic latent image formed on the latent image carrier.

Conventionally, an electrophotograph-type color-image forming method has been often used as a method for forming a color-image on a recording paper. The electrophotograph-type color-image forming method develops an electrostatic latent image formed on a latent image carrier by a developing device and the image formed on the latent image carrier by developer is finally transferred to paper fed.
A generally used color-image forming device employs the above method is an image forming device which (a) includes a plurality of latent image carriers in order to prevent deceleration of image forming speed, (b) uses different color materials as developer for the respective latent image carriers and (c) forms a color-image by superimposing images formed on the respective latent image carriers.
However, in recent years, many studies have been made to develop intermediate-transfer-type image forming devices in order to deal with varieties of sheets. The intermediate-transfer-type image forming devices do not transfer an image to a recording sheet directly from the latent image carrier, but ultimately transfers, to the recording sheet, a color image formed by superimposing images on the intermediate transfer member to which the images are temporary transferred. (For example, refer to the Japanese Laid-Open Patent Publication 209232/2001 (Tokukai 2001-209232 published on Aug. 3, 2001); corresponding U.S. Pat. No. 6,389,260 and the Japanese Laid-Open Patent Publication 154445/2001 (Tokukai 2001-154445 published on Jun. 8, 2001))
As an image forming device that employs an intermediate transfer system like this, a so-called tandem image forming device is generally used. Though there may be some difference in layout, the tandem image forming device, as illustrated in FIG. 8, is provided, along an intermediate transfer belt 304, with (i) an intermediate transfer belt 304 tensioned by tension rollers 302 and 303 between the rollers 302 and 303, which is used as a intermediate transfer, and (ii) plural image forming stations Pa, Pb, Pc, and Pd, which form images by respective different Color materials.
However, in spite of its high image forming speed, the conventional tandem image forming device has a problem in that a size of the device becomes large due to a large number of component parts.
Specifically in an intermediate-transfer type image forming device as in FIG. 8, an image formed at each image forming stations Pa, Pb, Pc, and Pd goes through the following processes: a) a primary transfer process where the image is temporarily transferred to an intermediate transfer belt 304 from photosensitive drums 222a, 222b, 222c, and 222d that are latent image carriers and b) a second transfer process where the image after the primary transfer process is transferred to recording paper P from the intermediate transfer belt 304. Thus, the image forming device including four latent image carriers as in FIG. 8 has five transfer processes because the primary transfer processes whose number of times is equivalent to the number of photosensitive drums 222a, 222b, 222c, and 222d and the second transfer process (a transfer process for transferring the images together at once) are carried out. Further, the respective image forming stations Pa, Pb, Pc, and Pd should be arranged such that the photosensitive drums 222a, 222b, 222c, and 222d and the intermediate transfer belt 304 are respectively provided with five cleaning devices (cleaning devices 226a, 226b, 226c, 226d and 221 in FIG. 8) for removing residual developer, which is not transferred but left over (remained). Accordingly, this causes a problem in that (a) the device tends to be large in size and (b) production cost increases due to a large number of component parts.

Image formation device and image forming method using same