A high-pressure metering pump for providing reductant in a single fluid engine exhaust dosing system having a solenoid for actuating a piston slidably received within an inner bore of a valve housing of the pump, the inner bore having a pressure chamber with an inlet check valve and an outlet check valve; and wherein movement of the piston causes high pressure reductant to be received at an atomizer of the system, the atomizer being disposed in a location to cause a maximum reduction of undesirable pollutant in the combustion gases of an engine.

Internal combustion engines emit undesirable pollutants in their exhaust stream. One such pollutant is nitrogen oxides such as nitrogen monoxide, nitrogen dioxide (hereinafter referred to simply as "NOx"). NOx is generated from automobile engines such as diesel engines, and large combustion apparatuses such as cogenerators. In addition, other combustion devices are sources of NOx emissions. Accordingly, exhaust systems are coupled to the engine to limit and/or remove the pollutants from the exhaust system. Technologies have been and continue to be developed to attenuate these emissions.
NOx is cleaned from exhaust gases of internal combustion engines through the use of catalysts. In addition to removing NOx, these catalysts also remove unburned hydrocarbons (HC) and carbon monoxide (CO). When the engine is operated with a lean air/fuel ratio, the catalyst is efficient at removing the HCs and COs because of the extra oxygen in the exhaust gas. However, the extra oxygen tends to inhibit the removal of NOx. Conversely, when the engine is operated with a rich air/fuel ratio, NOx removal efficiency of the catalyst is increased but the HC and CO removal efficiency is decreased.
In the case of exhaust gas from gasoline engines, NOx is usually removed by using so-called three-way catalysts. Also, in the case of large, stationary combustion apparatuses such as internal combustion engines for cogenerators, metal oxide catalysts such as V2O5 are used, and ammonia is introduced into exhaust gas, whereby nitrogen oxides in the exhaust gas are catalytically and selectively reduced.
However, in the case of an exhaust gas having a relatively high oxygen concentration such as those discharged from diesel engines and those discharged from gasoline engines operable in a lean state, efficient removal of NOx cannot be achieved with the above-described devices. Whereas homogeneous charge engines are able to utilize passive self-contained catalytic reduction techniques as exemplified by the three-way catalyst to control emissions of HC, CO, and NOx, so-called lean-burn engines as exemplified by the compression ignition engine may have high oxygen content in the exhaust which renders the conventional catalysis ineffective. In this case, techniques have been developed to meter an additional chemical reductant or reagent into the exhaust ahead of the reducing catalyst. In other cases, regeneration of an emissions control device, such as a particulate matter trap may require metered addition of a "fuel" ahead of an oxidizing catalyst in the exhaust stream so that necessary supplemental heat may be produced.
Conventional Selective Catalytic Reduction (SCR) of NOx involves injection of a typically aqueous urea solution or reductant into the exhaust system ahead of the SCR catalyst. Common reductants include aqueous urea in conjunction with selective catalytic reduction, and perhaps hydrocarbon diesel fuel for the supplemental heat necessary to initiate particulate trap regeneration. As used herein the term "urea" is meant to encompass urea in all of its commercial forms, including those containing: ammelide; ammeline; ammonium carbonate; ammonium bicarbonate; ammonium carbamate; ammonium cyanate; ammonium salts of inorganic acids, including sulfuric acid and phosphoric acid; ammonium salts of organic acids, including formic and acetic acid; biuret; cyanuric acid; isocyanic acid; melamine and tricyanourea.
The reductant dosing system is required to accurately meter the reductant into the exhaust system typically, while being responsive to the engine or after treatment control system. Further, it must present the reductant to the flowing exhaust gases in the most advantageous manner, which typically means that it must be finely atomized and well dispersed. A key requirement is that it should be fully decomposed by the time it reaches the catalyst, so that it may work with immediate effect, and that it should be homogeneously dispersed so that all active sites on the catalyst are engaged equally and non-preferentially to achieve maximum catalyst utilization.
Another requirement is that the reductant must be delivered in a manner that prevents clogging of the atomizer. This is due to the chemical composition of the reductant, which when exposed to heat may be affected by pyrolysis wherein the atomizer may become clogged.
Accordingly, most dosing systems have been designed for delivery of reductant in a two fluid system, namely the reductant and a supply of pressurized air. In most cases these systems utilize an air pressure assisted atomizer to achieve the quality of atomization and dispersion required, as well as meeting the operational robustness target specified. Such systems make use of the metering pump for delivering the reductant into a mixing chamber where it co-mingles with pressurized air from an onboard source such as may be required for an air-brake system or air-suspension in automotive applications. This mixture is conducted through a pipe to the remote dosing location in the exhaust where it exits through a simple atomizing nozzle into the exhaust stream. A typical air atomizing pressure for this type of system might be 2 bar.
Advantages of the known air-assisted or two fluid dosing systems include the ability to use a very simple and robust atomizing nozzle. Disadvantages include the need for air pressure in all applications, even those where the pressurized air is not normally available. Typically, the generation of air pressure requires expensive components which are heavy, bulky, noisy, and energy inefficient. Further, it is only applicable to in-exhaust injection, and is not suitable for in-cylinder injection which may be another similar viable emissions reduction technology.
Therefore, it is desirable to develop an efficient apparatus and method for reducing NOx contained in the exhaust gas or combustion gas of an internal combustion engine or other device requiring such an exhaust system while giving consideration to the aforementioned requirements.

Apparatus and method for reductant dosing of an exhaust


A process for producing high-resistance SiC from low-resistance SiC starting material. The flat (shallow) donor levels of a prevailing nitrogen impurity are overcompensated by admixture of a trivalent doping element with the concentration of the doping element in the SiC being such that it changes the conductivity type from a n-conductivity to a p-conductivity. In addition, a transition element is added having donor levels approximately in the middle of the SiC energy gap, so that the excess acceptor levels are in turn compensated and a high specific resistance is achieved.

The invention relates to a process for producing high-resistance silicon carbide (SiC) from a low-resistance silicon carbide starting material.
SiC in crystalline form has properties of a semiconducting material and is increasingly employed in various semiconductor structural elements. For many applications it is desirable that the substrate, i.e., the starting crystal, be a disk of a high-resistance material. This monocrystal then can serve as the: common substrate for a plurality of individual structural elements which are electrically insulated. Many processes which are performed with pure Si, for example, can be transferred to SiC, i.e., in detail, masking technique with a thermal oxide, ion implantation, dry etching of structures, epitaxia growth and contacting.
The understanding of defects with low levels in the energy gap of SiC is still very incomplete. For example, little is known about transition elements in SiC, either regarding their defect structure (substitutionally or interstitially) or their suspected electrical activity as interference locations with states energetically located far below the conductivity band. An important characteristic of SiC is its polytypicism, i.e., its occurrence in several modifications. Hexagonal 4H- and 6H-SiC with an energy gap of 3.0 eV, and cubic 3D-SiC with an energy gap of 2.4 eV are of interest in connection with electronic applications. Very little is known in particular about the level position of titanium impurities, which are practically unavoidable with deep-drawn SiC. The knowledge and control of impurities with low energy levels, however, is absolutely required in order to assure the quality of opto-electronic and electronic structural elements on the basis of SiC.
It is known from the publication by J. Schneider. H. D. Muller, K. Maier, W. Wilkening, F. Fuchs, A. Dornen, S. Leibenzeder and R. Stein, Appl. Phys. Lett., 56 (1990) p. 1184, that vanadium impurities can occur in SiC crystals in the form of amphoteric impurities with low energy levels. This means that at least three different charge states of vanadium occur in SiC. Two new levels are created in the energy gap by means of vanadium. Based on this it was suspected that vanadium can reduce the life of minority carriers in SiC. In a later publication by K. Maier, J. Schneider, K. Wilkening, S. Leibenzeder and R. Stein "Electron Spin Resonance Studies of Transition Metal Deep Level Impurities in SiC", Materials Science and Engineering B11 (1992), pp. 27 to 30, these levels are also researched. This also does not contain any suggestions for purposefully inserting impurities in p-doped 4H- and 6H-SiC in order to compensate them electrically and to produce high-resistance SiC.
From U.S. Pat. No. 3,344,071 it is known how it is possible to produce high-resistance material from GaAs crystals drawn from the melt by purposeful doping with chromium. In connection with the n-type GaAs it is necessary to additionally admix a substance acting as an acceptor.
It is unknown so far how, in the case of SiC, the effects of flat (shallow) interference locations can be canceled and high-resistance material generated.

Process for producing high-resistance silicon carbide


The invention provides method of diagnosing a receptor tyrosine kinase (RTK)-hyperfunction-induced disorder or a genetic predisposition therefor in a mammal. The method comprises determining the presence of a nucleic acid encoding a mutated fibroblast growth factor receptor-4 (FGFR-4) protein in a nucleic acid sample from a mammal. The presence of a nucleic acid encoding a mutated FGFR-4 protein is indicative of an RTK-hyperfunction-induced disorder or a genetic predisposition therefor.

The present invention concerns the use of inhibitors for the treatment and/or prophylaxis of diseases which are the consequence of increased receptor tyrosine kinase activity, particularly cancer. The use is particularly directed towards inhibition or lowering of the overexpression and/or altered activity of receptor tyrosine kinases (RTKs). In particular, this altered activity of receptor tyrosine kinase can be triggered by a mutation of FGFR-4, wherein this mutation is in particular a point mutation in the transmembrane domain of FGFR-4 and leads to the exchange of a hydrophobic amino acid for a hydrophilic amino acid. The invention further concerns the use of the inhibitors of FGFR kinases, particularly for the treatment and/or prophylaxis of cancer. Furthermore, the invention concerns a mutated FGFR-4, which leads to overexpression and/or altered activity in cells. Finally, the invention concerns a DNA and RNA sequence of a mutated FGFR-4 molecule. Finally, in addition the invention concerns a pharmaceutical composition, containing the inhibitor as described above and, further, a diagnostic and screening procedure.
Cell growth is a carefully regulated process dependent on the specific needs of an organism. In a young organism, the cell division rate exceeds the cell death rate, which leads to an increase in the size of the organism. In an adult organism, the new formation of cells and cell death are balanced so that a "steady state" arises. In rare cases, however, the control of cell multiplication breaks down and the cells begin to grow and to divide, although no specific need for a higher number of cells of this type exists in the organism. This uncontrolled cell growth is the cause of cancer. Factors that can provoke the uncontrolled cell growth, some-times associated with metastasis formation, are often of a chemical nature, but can also be of a physical nature, such as for example radioactive radiation. Another cause of the triggering of cancer are genetic peculiarities or mutations in a certain organism, which sooner or later lead to the cells degenerating.
Up to now, it has still not been possible satisfactorily to elucidate the processes which control normal growth and differentiation, for example in the breast. In addition to hormonal control, there is also a complex network of different, locally generated growth factors which intervene in the development of the mammary cells. The precise causes of the occurrence of cancer in mammary cells are as unclear and unknown as they are diverse, as is also the case with other cells. Alterations in oncogenes and tumour suppressor genes appear to play an important part in breast cancer carcinogenesis. In addition, reinforced stimulation by regulatory factors which arise in genetically altered cells can lead to increased progression of cell growth.
At present, essentially two alternatives are available for the treatment of cancer. Either the cancer cells are successfully removed from the diseased organism completely by a surgical intervention, or attempts are made to render the degenerated cells in the organism harmless, for example by administration of medicaments (chemotherapy) or by physical therapeutic procedures, such as irradiation.
In chemotherapy, medicaments are often used which in some form intervene in the DNA metabolism and damage rapidly growing cells, which have to produce higher DNA metabolic capacity, more strongly than cells which are dividing slowly or not at all. However, a severe disadvantage of many chemotherapeutic drugs is the low specificity of the active substance used, as a result of which healthy cells are also damaged during the chemotherapy. This low specificity of the active substances further requires that their dosage must in each case be such that as few as possible healthy cells are damaged, with simultaneous killing of the cancer cells. This is often not possible, and the cancer patient dies because of the ever further spreading cancer cells, which in the final stages cause the failure of vital functions.
It is assumed that the overexpression and/or altered activity of certain growth factor receptors contribute to the intensified growth of many neoplasms, including breast cancer. For example, the overexpression of EGFR, i.e. epidermal factor receptor, or ERB B-2 receptor in breast tumours has been linked with a poor prognosis. FGF (historically: fibroblast growth factor) proteins could also be involved in the development of cancer in breast glands or of other cancer; however the results in this regard are contradictory or are inconclusive.
The FGFs constitute a large family of peptide regulatory factors, of which 9 members are so far known. Eight of these have been well characterised in man (Basilico and Moscatelli, 1992; Coulier et al., 1993). The FGFs operate via high-affinity tyrosine kinase receptors, which are coded for by at least four different genes. Further, the FGFs are multifunctional, regulatory peptides which could have an effect not only on tumorigenesis but could also play a major part in cardiovascular diseases, reconstruction after tissue injury, neurobiology and embryonic development. The acidic and basic FGFs (aFGF and bFGF) were the first and are the best characterised members of the family. In vivo it could for example be shown that FGFs are involved in mesodermal induction in embryogenesis (Slack et al., 1987; Kimelman et al., 1988), and also involvement in angiogenesis (Thomas et al., 1985; Thompson et al., 1989; Folkmann and Klagsbrun, 1987).
For the corresponding receptors (FGFRs), four similar genes coding for them have been identified. These genes code for structurally related proteins with an extracellular domain which consists of three immunoglobulin loops and an acid portion, a hydrophobic trans-membrane domain and an intracellular domain, which incorporates a tyrosine kinase activity. For two of these genes, FGFR-1 and FGFR-2, it could be shown that they have multiple transcripts, which arise by alternative splicing (Givol and Yayon, 1992 and Johnson and Williams, 1993). Splice variants which arise from these genes differ with respect to the number of immunoglobulin-like domains in the extracellular region of the receptor and in the sequence for the second half of the third immunoglobulin domain, which can arise from alternative exons. In addition, transmembrane and juxtamembrane shortenings or deletions can arise, which can generate secreted or kinase-inactive protein products.
For FGFR-3, it was possible to find alternative transcripts and corresponding isoforms, but for FGFR-4 there is only a single known protein product. Because of the large number of FGFR genes and transcripts and the lack in many protein products of a specificity for defined FGFs, it is difficult to determine the action of a specific ligand on a specific receptor. Hence, correlations between specific FGF receptors and defined diseases can only be established with great difficulty, let alone a correlation of a particular mechanism of action of a defined receptor with a disease. Accordingly, it is difficult effectively to treat diseases, especially the complex disease picture cancer, utilising the FGFRs.

Method of diagnosing an RTK-hyperfunction induced disorder

Max-Planck-Gesellschaft zur Forderung der Wissenschaften E.V.


A protection diode is used in a CMOS integrated circuit device to direct charged particles to benign locations and prevent damage to the device. The protection diode includes a well region of a first conductivity type formed in a surface of a semiconductor substrate, a heavily doped P-type impurity region disposed within the well region, a heavily doped N-type impurity region disposed within the well region and an STI structure interposed therebetween. A top surface of the STI structure extends above the surface. A silicide resistant block-out layer is formed over the STI structure and extends laterally beyond the STI structure, covering any counterdoped sections that may undesirably be formed in the substrate adjacent the STI structure during implantation operations. The method for forming the structure utilizes processing operations and materials used in the formation of the CMOS integrated circuit device.

During the fabrication of CMOS devices, various processing steps such as plasma deposition and plasma etching can deleteriously influence underlying components of uncompleted CMOS devices. Charged particles, generated during such plasma procedures, can damage the already formed thin gate insulator layers used for the CMOS devices, for example. Protection devices such as protection diodes can be used to guide the unwanted currents generated by the plasma procedures to benign locations in the semiconductor substrate, thus not adversely affecting CMOS device yield or performance.
It is advantageous to form the protection device at an early stage of the CMOS device fabrication sequence so that they are in place during as many of the subsequent plasma processes as possible. Subsequent processing steps such as the formation of heavily doped source/drain regions can counterdope unprotected regions of a protection device such as a diode which, when overlaid with a conductive layer such as metal silicide, can result in unwanted leakage of the protection device, thus reducing or eliminating the ability of the protection device to protect the sensitive components of CMOS devices.
Fringe type protection diode structures include a doped portion formed in regions of a semiconductor substrate surrounded by shallow trench isolation (STI) regions, and are particularly vulnerable to counterdoping phenomena during the subsequent source/drain formation procedures that involve heavy doping. The topography at the interface between the STI, which extends above the substrate surface, and the protection device, formed in the substrate surface, can present problems when attempting to completely cover the protection diode device with a photoresist shape for blocking-out subsequently implanted species used in the formation of heavily doped CMOS source/drain regions, for example. The photoresist shape can become notched, or thinned at this topographical interface allowing unwanted species to enter the peripheral regions of the protection diode device near the interface. If the undesirably implanted species is of opposite conductivity (i.e., counterdoping occurs) a subsequent metal silicide contact layer formed to overlay both the main doped portion of the protective diode, and the oppositely doped component at the periphery, provides a direct path through the protection diode device to regions of the semiconductor substrate, negating the purpose of the protection diode.
The present invention advantageously provides a structure and procedure whereby the protection diode structure, even if undesirably counterdoped during subsequent implant procedures, still remains effective after formation of an overlying metal silicide layer, and therefore still functions to direct any unwanted charge generated during subsequent plasma procedures, to non-CMOS regions of the semiconductor substrate. This is accomplished via masking procedures obtained using no additional process or masking steps. References such as Voldman et al, in U.S. Pat. No. 5,629,544, Chang et al., in U.S. Pat. No. 6,294,448, Wang et al., in U.S. Pat. No. 6,291,281 and Jang, in U.S. Pat. No. 6,093,593, describe methods of forming protective structures, or describe materials used to avoid leakage paths through protection diode devices, but fail to provide a structure that effectively prevents an overlying conductive layer, such as metal silicide, from shorting the counterdoped region of the protection diode structure to an underlying well region. The present invention addresses this shortcoming of conventional technology.

Semiconductor device with reduced leakage protection diode

Taiwan Semiconductor Manufacturing Co., Ltd.


This invention relates to a composition for the preservation of a virus, the composition including a virus, a lipid and a cryoprotectant.

Gene therapy broadly refers to the transfer of genetic material into cells and the expression of that material in those cells for a therapeutic purpose. The goal is to produce the desired protein in the appropriate quantity and the proper location. Although a variety of methods have been developed to deliver therapeutic nucleic acids to cells, many of these methods are limited by relatively inefficient transfer of the therapeutic nucleic acid to the target cells. Because viruses are highly efficient at infecting susceptible cells, viruses are now recognised as being useful vehicles for the transfer of therapeutic nucleic acids into cells for the purpose of gene therapy.
Viruses fall broadly into two distinct groups: those that integrate into the genome of transduced cells and those that do not. An integrating virus inserts its viral genome into host DNA to facilitate long-term gene expression. For a non-integrating virus, however, the viral genome exists extra-chromosomally as an episome in the nucleus of transduced cells. Depending on the ability of the virus to replicate, the viral genome is either passed on faithfully to every daughter cell or is eventually lost during cell division.
Retroviruses and adeno-associated viruses (AAVs) may integrate into the host DNA to provide a steady level of expression following transduction and incorporation into the host genome. As the target DNA is replicated, so too is the inserted therapeutic gene embedded in the transferred chromosomal DNA. Thus, transduction via these vectors can produce durable gene expression. This can be advantageous in tumour vaccine strategies in which a steady level of gene expression may enhance efficacy.
In contrast, adenovirus and vaccinia virus vectors do not integrate into the host DNA but exist as episomes. Thus, a transferred gene is expressed without actual integration of the gene into the target cell genome. Generally, non-integrating viruses are used when transient gene expression is desired.
Examples of viruses that may be used to deliver nucleic acids to cells for gene therapy purposes include adenovirus, adeno-associated virus (AAV), retrovirus, herpes simplex virus, vaccinia virus, poliovirus, sindbis virus, HIV-1, avian leukosis virus, sarcoma virus, Epstein-Barr virus, papillomavirus, foamy virus, influenza virus, Newcastle disease virus, sendai virus, lymphocytic choriomeningitis virus, polyoma virus, reticuloendotheliosis virus, Theiler's virus, and other types of RNA and DNA viruses.
The use of attenuated and killed viruses for purposes of vaccination is also well known. In addition, viruses are also becoming increasingly important as tools for research and diagnostics. The increasing importance of viruses as tools for gene therapy, vaccination, and research and diagnosis has led to a need to develop viral compositions that may be manufactured, stored and used without compromising viral efficacy. For example, viral compositions for vaccination must be able to maintain the immunogenicity of a virus, or the immunogenicity of a component of the virus. In the case of compositions of viruses to be used for gene therapy, it is critical that the efficacy of the live viral formulations carrying therapeutic transgenes be maintained.
Because viruses are biological entities consisting of a nucleic acid encapsulated by a protein coat, they are susceptible to the same chemical and physical processes that may degrade or inactivate proteins and nucleic acids. In particular, live viruses may often be very susceptible to damage, as any change in the conformation or integrity of one or more components of the virus coat or the encapsulated nucleic acid may lead to a loss of infectivity. As such, biopharmaceutical products containing compositions of viruses for vaccination or gene therapy usually require stringent conditions to avoid physicochemical degradation and to maintain biological activity. Degradation of viruses in such compositions may occur during isolation, production, purification, formulation, storage, shipping or delivery of the virus. Accordingly, biopharmaceutical compositions of viruses must be formulated to provide protection of the virus against factors such as temperature, pH, pressure, oxidising agents, ionic content, light, radiation, ultrasound, and changes in phase (for example as occurs during freezing and thawing ("freeze-thawing").
In addition to the factors already discussed, other factors such as viral concentration, the size and structure of the encapsulated nucleic acid, container composition, headspace gas, and number of freeze-thaw cycles may all affect the activity of viral compositions.
As a consequence, the utility of many viruses in biopharmaceutical preparations is often limited by the instability of compositions of the viruses, particularly upon storage. For example, even when viral compositions are stored at very low temperature (for example −80° C.) in the frozen state, a significant loss of infectivity may still occur over time. A further loss of infectivity may occur upon thawing of the frozen viral composition.
In addition, as low temperature storage conditions are not always available, it would be advantageous to develop formulations that improve the preservation of frozen viral formulations above −80° C. for extended periods of time, such as extended storage at temperatures just below freezing. Indeed, viral compositions that must be stored at very low temperature and cannot be stored at standard freezer temperatures (for example −10° C. to −20° C.) for substantial periods of time represent a serious impediment to the widespread clinical use of many viruses.
As will be also appreciated, the storage of products at standard freezer temperatures may also be problematic, because often such freezers undergo temperature cycling that may result in the viral composition being subjected to temperatures above freezing, and as such the compositions may undergo repeated cycles of freezing and thawing. Freeze-thawing may also occur during large scale production, handling or distribution.
It would also be advantageous to develop viral compositions that can maintain the desired pH of the composition for extended periods of time despite being exposed to refrigeration temperatures and/or subjected to conditions such as freeze-thawing, especially the slow rate of freeze-thawing that may occur during large scale production, handling or distribution.
Finally, increasingly high concentrations of virus are also being required for therapeutic purposes. However, the concentration of virus in a composition may present additional problems to the ability to preserve a virus. In particular, a high concentration of virus may contribute significantly to viral instability due to aggregation and/or precipitation.
Therefore for many viruses a deficiency has been the inability to formulate compositions that acceptably preserve the virus, particularly in the frozen state. Such deficiencies with the ability to preserve the activity of viral compositions often preclude their use for gene therapy, for vaccination, or for other purposes.
It is therefore an aim of the present invention to provide a composition for the improved preservation of viruses.
Throughout this specification reference may be made to documents for the purpose of describing various aspects of the invention. However, no admission is made that any reference cited in this specification constitutes prior art. In particular, it will be understood that the reference to any document herein does not constitute an admission that any of these documents forms part of the common general knowledge in the art in Australia or in any other country. The discussion of the references states what their authors assert, and the applicant reserves the right to challenge the accuracy and pertinency of any of the documents cited herein.

Composition for the preservation of viruses


An optimization design method for a spatial flow passage of a low-pressure even spray nozzle, relating to a design method for an essential apparatus in a water-saving irrigation system, such as a spray irrigation system. Specifically, if the model and the inlet diameter of a nozzle are determined, the shape and the size of the cross section of an outlet, a flow passage deflection angle, the radius and the arc length of a flow passage contour, and the size of an elevation angle of the outlet are determined to implement structural optimization of a spatial flow passage of the nozzle; moreover, parameterization design of the spatial flow passage in different inlet diameter conditions is implemented, so that a method for determining structural parameters of a spatial flow passage of a nozzle is obtained. A design method of a spatial flow passage under a low-pressure operation condition is developed, such that the hydraulic performance of the nozzle is optimized, and the nozzle is efficient and saves energy.

China is a great agricultural country with a large population, and is confronted with a severe water shortage problem. Therefore, promoting water-saving irrigation is crucial in the development of agricultural technology in China. The sprinkler irrigation technique is one of efficient water utilization techniques available at present. The irrigation quality of a sprinkler irrigation system depends on the hydraulic performance and operational performance of spray nozzles to a great extent, the spray nozzles are key devices for implementing sprinkler irrigation.
The flow passage of a spray nozzle accomplishes pressure water inflow, turning, energy exchange, and jetting. The structural form, physical dimensions, cross-sectional shape, and surface roughness, etc., of the flow passage have influence on the hydraulic performance of the spray nozzle. In order to reduce internal hydraulic loss in the flow passage of spray nozzle and realize optimization of hydraulic performance, for a small-size low-pressure spray nozzle, a water smashing mechanism is often mounted outside of the nozzle, or a special-shaped nozzle is used, or a tapered cut is worked out at the nozzle, etc., to improve atomization performance of the spray nozzle and increase the water volume near the spray nozzle, but the sprinkling range is often reduced to some extent.
Presently, the structural design in the research mainly focuses on design of auxiliary nozzle, multi-passage technique, water dispersion mechanism, and special-shaped nozzle, etc. However, an optimization design of parameters of spatial flow passage of the spray nozzle can improve hydraulic performance and operating stability of the spray nozzle. Though such an optimization design ought to be regarded as a key concern in the design process, there is few relevant research. In order to solve the above-mentioned problem, the present invention provides a design method for a spatial flow passage of a low-pressure even spray nozzle, so as to overcome the drawbacks of poor evenness and short sprinkling range of spray nozzles in the prior art; in addition, the design method is of far reaching importance for improving the design of flow passages of spray nozzles.
No relevant patent application is found in the patent search carried out by the inventor.

Optimization design method for spatial flow passage of low-pressure even spray nozzle


A humidity detection sensor includes a lower electrode provided on a board, an upper electrode provided so as to face the lower electrode, a humidity sensing film which is formed at least between the lower electrode and the upper electrode and whose dielectric constant changes in response to humidity, and a protective film provided so as to cover the upper electrode. Each of the upper electrode and the protective film has an opening through which the humidity sensing film is partially exposed to the outside. In the opening, the humidity sensing film is provided so as to reach at least a position higher than the position of the lower surface of the protective film.

1. Field of the Invention
The present invention relates to a humidity detection sensor including a dielectric substance as a humidity sensing film and a method for manufacturing the same.
2. Description of the Related Art
As a humidity detection sensor used for measuring a humidity change, there is a capacitance type humidity detection sensor including a dielectric substance as a polymer humidity sensing film whose dielectric constant changes in response to an amount of absorbed or discharged water. The capacitance type humidity detection sensor includes a sensor section whose capacitance changes in response to humidity; and a reference section that keeps its capacitance constant regardless of humidity. The capacitance type humidity detection sensor converts the capacitance difference between the sensor section and the reference section to a voltage and outputs the voltage. Each of the sensor section and the reference section has a lamination structure in which a polymer humidity sensing film is interposed between a pair of electrodes. Such a humidity detection sensor is disclosed, for example, in PCT Japanese Translation Patent Publication No. 2003-516538.
As disclosed in PCT Japanese Translation Patent Publication No. 2003-516538, as the structure of the humidity detection sensor, there is a structure in which a pair of opposed comb electrodes are provided on the same plane and a humidity sensing film is provided on the pair of comb electrodes, or a structure in which a humidity sensing film is provided between a lower electrode formed on a board and an upper electrode provided on the lower electrode so as to face the lower electrode.
The structure in which the humidity sensing film is provided between the upper and lower electrodes is formed by laminating the lower electrode, the humidity sensing film, and the upper electrode in order, and thus it is possible to easily control the thickness and smoothness of the humidity sensing film as compared to the case where the humidity sensing film is provided on the comb electrodes provided on the same plane. Meanwhile, in the case of the parallel-plate structure in which the humidity sensing film is interposed between the upper and lower electrodes, the upper electrode is exposed, and thus a problem of humidity resistance, such as corrosion of the upper electrode due to water or the like, arises.
As a solution to the problem, it is conceivable to form a protective film on the upper electrode of the sensor section. However, as described in PCT Japanese Translation Patent Publication No. 2003-516538, in the parallel-plate structure in which the humidity sensing film is provided between the upper and lower electrodes, when the upper electrode is partially removed to partially expose the humidity sensing film, thereby smoothly supplying water molecules to the humidity sensing film, if a protective film is formed over the entire surface, external water molecules cannot smoothly be supplied to the humidity sensing film. Meanwhile, a method of selectively forming the protective film only on the upper electrode is conceivable. However, in this case, a problem of corrosion from side surfaces of the exposed upper electrode is considered.

Humidity detection sensor and a method for manufacturing the same


In one aspect the embodiments of the invention provide a method that includes transmitting a first frame comprising a first type of message from a first node for reception by a second node. The first node is associated with a first wireless communication system and the second node is associated with a second wireless communication system. The first type of message includes a first information element for identifying the second node and a second information element for specifying that the first frame is transmitted to initiate a request for simultaneous transmission by the first node and by the second node. The first frame is also received by a third node that is part of the first wireless communication system. The method further includes receiving from the third node a second frame that includes a second type of message. The second type of message identifies the second node and specifies, based on a measurement performed by the third node on the first frame and a measurement performed by the third node on a third frame transmitted by the second node, whether the request for simultaneous transmission is accepted or is not accepted by the third node. The method further includes transmitting a fourth frame that includes the second type of message from the first node for reception by the second node. The second type of message identifies the second node and specifies that the request for simultaneous transmission was accepted by the third node.

This section is intended to provide a background or context to the invention that is recited in the claims. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented or described. Therefore, unless otherwise indicated herein, what is described in this section is not prior art to the description and claims in this application and is not admitted to be prior art by inclusion in this section.
The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:
AP: Wi-Fi Access Point
BSS: Basic Service Set
CdW: Contention Window
CCA: Clear Channel Assessment
CST: Clear-to-Simultaneous-Transmission
DCF: Distributed Coordination Function
DIFS: DCF Interframe Space
FCS: Frame Check Sequence (Cyclic Redundancy Check (CRC))
LTE: Long Term Evolution
MAC: Medium Access Control
MCS: Modulation Coding Scheme
NAV: Network Allocation Vector
OBSS: Overlapping-BSS
RA: Receiver Address
RST: Request-Simultaneous-Transmission
SIFS: Short Interframe Space
STA: Wi-Fi Station (non AP)
STW: Simultaneous Transmission Window
TA: Transmitter Address
The IEEE 802.11 standard for Wireless Local Area Networks (WLANs), commonly known as Wi-Fi, has been broadly adopted to provide users with wireless broadband access to the Internet. With the increase on the demand for wireless Internet access, dense Wi-Fi deployments have become more common in both residential and office environments. For a dense Wi-Fi deployment there can be a high density of Wi-Fi terminals and networks operating without coordination and with overlapping coverage.
In a typical mode of Wi-Fi operation an Access Point (AP) bridges a Basic Subscriber Set (BSS) of wireless stations (STAs) to a wired Ethernet network. Wi-Fi uses a contention-based channel access protocol known as Carrier Sensing Multiple Access with Collision Avoidance (CSMA/CA). In CSMA/CA operation Wi-Fi nodes need to 'listen' to a channel prior to transmitting. This procedure is known as Clear Channel Assessment (CCA). Nodes in CCA may receive transmissions from one or more other nodes. These received transmissions are understood to indicate that the channel is occupied. In response to the channel being occupied the node defers its own transmission for some random duration of time (known as backoff).
One approach employs DCF that uses a CSMA/CA with a binary exponential backoff algorithm. DCF requires a station wishing to transmit to listen for the channel status for a DIFS interval. If the channel is found busy during the DIFS interval, the station defers its transmission. In a network where a number of stations contend for the wireless medium, if multiple stations sense the channel busy and defer their access, they will also virtually simultaneously find that the channel is released and then try to seize the channel. As a result, collisions may occur. In order to avoid such collisions, DCF also specifies random backoff, which forces a station to defer its access to the channel for an extra period.
As can be appreciated the backoff situation occurs more frequently in a dense deployment with overlapping BSSs (OBSSs), which causes a degradation of Wi-Fi performance in terms of throughput, latency and user quality of service (QoS).

Method and apparatus to coordinate simultaneous transmission in overlapping wireless networks


A process for preparing a mesoporous silica comprising contacting as starting components (1) a structure-directing template selected from the group consisting of hydrogenated and non-hydrogenated natural vegetable oils, silicone oils, and combinations thereof; (2) water; (3) silica; and, optionally, (4) a structure-directing co-template selected from tetramethylammonium hydroxide, tetraethylammonium hydroxide, tetrapropylammonium hydroxide, cetyltrimethylammonium bromide (CTAB), hexadecyltrimethylammonium chloride; hexadecyltrimethylammonium hydroxide hydrate, hexadecyltrimethylammonium p-toluenesulfonate, hexadecyltrimethylammonium bis-sulfonate, poloxamers having a weight average molecular weight ranging from 5,000 to 20,000 Daltons (Da), and combinations thereof; in the substantial absence of an alcohol solvent; under conditions such that a mesoporous silica having an average pore diameter ranging from 50 to 175 angstroms and a pore diameter distribution that, within one standard deviation of its mean, is substantially unimodal, is formed. The product composition may offer preferred use in, for example, gas separations, sensing, water purification, heavy metal removal, and electronics, where its narrower pore diameter distribution increases its selectivity.

Field of the Invention
This invention relates to the field of mesoporous silicas. More particularly, it relates to mesoporous silicas prepared using natural and synthetic oils, having relatively large pore diameters and relatively narrow, substantially unimodal pore diameter distribution ranges.
Background of the Art
Mesoporous materials have been known to researchers for many years, and are used for a variety of applications. In general these materials are inorganic solid materials characterized by a porous structure which is formed of channels or pores that frequently have average diameters in a general range of from 2 to 50 nanometers (nm). These channels or pores may be relatively uniform, with fairly constant diameters, or non-uniform, with a variety of diameters. The porous structure provides for a large internal surface area with adsorptive capacity for molecular species which are capable of entering therein.
Mesoporous materials may be amorphous or crystalline. Examples of mesoporous materials include synthetic and natural crystalline pure silicates and aluminosilicates. Such may also be referred to as framework aluminosilicates, where the framework is based on a three-dimensional network of [(Al,Si)4] tetrahedra which are linked to each other, at their corners, by shared oxygen atoms.
However, despite successful use of such mesoporous silica materials in certain applications, some of these materials suffer from less than desirable selectivity. Such may be due to, for example, less than desirable uniformity in pore diameters, i.e., broad pore diameter distributions, or to pore diameters that are too small for larger molecules, such as certain biomolecules. In view of this, it is desirable to develop new means of modifying silica-based mesoporous materials to reduce or eliminate one or more of these problems.

Compositions and processes for mesoporous silicas having large pores with narrow diameter distributions


A display control apparatus displays, together with an image on a display unit, items related to a plurality of objects in the image. At this time, for the plurality of objects in the image, the display control apparatus displays items related to the respective objects at display positions having a predetermined relative positional relationship with the objects. The display control apparatus decides the order of priority of the plurality of objects. In case that the area of a main object having a highest decided priority level and the display position having the predetermined relative positional relationship for an item related to another object overlap each other, the display control apparatus adjusts the display position of the item related to the other object to eliminate the overlapping, and displays the item related to the other object.

Field of the Invention
The present invention relates to a display control apparatus, image capture apparatus, display control method, and image capture apparatus control method.
Description of the Related Art
Recently, there is known an image capture apparatus which recognizes that a captured object is a person, and provides various value-added functions to the person object. Japanese Patent Laid-Open No. 2009-110147 discloses an image capture apparatus which performs processing of associating attribute data of a registered person with face image data detected by a face detection means, and displays a mark image and name data corresponding to it near a face area corresponding to the registered face image data.
However, when many faces exist in one frame or objects exist densely, the ratio of the name display area to the image becomes high, the name display overlaps the important person face, making the display less visible. When pieces of information to be displayed are dense, a personal computer or the like gives priority to objects, and superposes and displays them, which is generally known as a multiwindow system. Japanese Patent Laid-Open No. 11-015626 discloses an arrangement in which display objects are automatically aligned and displayed, in addition to control of the multiwindow system.
However, by simple alignment, the display positions of an object and information related to the object are spaced apart from each other, and their relation becomes unclear. To solve this, more complicated display control is required to arrange display information while maintaining the relation with an object.
For an image capture apparatus having restrictions on the manufacturing cost and battery capacity, it is also important to suppress the performance of a mounted arithmetic device and the operating load on the arithmetic device. Hence, in image capturing accompanied by live view display which particularly requires high processing ability in real time, it is necessary to allocate the ability of the arithmetic device to image capture processing as much as possible, and avoid execution of complicated display control as described above.

This patent is subject to a terminal disclaimer.

Display control apparatus, image capture apparatus, display control method, and image capture apparatus control method


An elevated transistor formation includes a plurality of planes upon which transistors are formed. The plurality of transistor planes are formed at multiple relative elevations overlying a substrate wafer using deposited polysilicon to form a substrate between the layers. The polysilicon is deposited in a multiple-grain form to achieve an advantageous balance between deposition rate and substrate quality. In particular, columnar polysilicon is deposited at a temperature of approximately 620.degree. C. and above to achieve a high deposition rate directly overlying a lower-elevation transistor plane. High quality polysilicon is then deposited overlying the columnar polysilicon layer at a temperature of approximately 580.degree. C. or below. The deposition rate for high quality polysilicon is substantially lower than the deposition rate for columnar polysilicon. The highest quality substrate, upon which transistors in an elevated transistor plane are formed, is amorphous polysilicon.

1. Field of the Invention
The present invention relates to an integrated circuit and fabrication method. More specifically, the present invention relates to an integrated circuit including transistors formed in a plurality of planes overlying a substrate using a graded grain structure to form a semiconductor region between the transistor planes.
2. Description of the Related Art
Polysilicon is deposited as a semiconductor substrate during fabrication of integrated circuits using a chemical vapor deposition (CVD) technique. The structure and properties of polysilicon are determined by CVD characteristics including deposition temperature, and dopant type and concentration. The structure and properties of polysilicon are also determined by thermal cycling operations performed subsequent to chemical vapor deposition. Typical polysilicon deposition processes are performed at a temperature range from approximately 600.degree. C. to 650.degree. C. Deposition is made from a silane (SiH.sub.4) silicon source, generally either a 100% silane source or silane in combination with nitrogen (N.sub.2) or hydrogen (H.sub.2) gas streams. At temperatures below 580.degree. C. the as-deposited film is amorphous. At temperatures above 580.degree. C. the films deposit as polycrystalline silicon with formation of small pockets called crystallites or grains of single-crystalline silicon separated by grain boundaries. Polysilicon having a crystallite structure is commonly called columnar polysilicon.
The crystals in polysilicon deposit in a preferred orientation which depends on the deposition temperature. At temperatures in the range from 580.degree. C. to 600.degree. C., a {311} preferred orientation is produced. The polycrystalline silicon is dominated by crystals with a {110} fiber axis with columnar grains for temperatures in the 625.degree. C. range while a {100} orientation predominates in the 675.degree. C. range.
Amorphous polysilicon films are recrystallized at temperatures from 500.degree. C. to 1000.degree. C. and tend to produce a crystalline structure having a strong {111} fiber texture. The texture and grain size are highly reproducible in polysilicon films that are crystallized from amorphous phase films, producing a grain size that is generally larger than the grain size of as-deposited films. As-deposited amorphous films tend to have a smoother surface than films grown at less than about 580.degree. C. which occasionally have rough surfaces and films grown at 620.degree. C. which always have a rough surface. The smooth surface of as-deposited amorphous polysilicon films is maintained even after annealing at temperatures from 900.degree. C. to 1000.degree. C. The smooth surface of an as-deposited amorphous film is attained at the expense of a slower deposition rate at a temperature of 580.degree. C.
In addition to temperature, deposition and processing parameters including source concentration, pump speed, nitrogen flow, and other gas flows determine the deposition rate and grain size. For example, application of hydrogen (H.sub.2) in the gas stream advantageously reduces the occurrence of surface impurities and moisture which in turn results in a reduced grain size. Moisture or oxygen impurities cause growth of silicon dioxide within the polysilicon, increasing the resistance of the polysilicon and increasing etchability in subsequent masking steps.
The presence of dopants in the gas stream influence the grain size. Typically a strip of polysilicon is used in integrated circuits to function as a conductor. Doping is used to decrease resistivity of the polysilicon.
The quality of polysilicon in terms of characteristics including grain size and grain boundary consistency determines the electrical performance of devices constructed in the polysilicon based on the electrical current flow characteristics of the films. Current resistance arises as electrical current crosses grain boundaries in the polysilicon with larger grain boundaries being associated with a higher resistance. The fabrication of integrated circuits having a consistent current flow from device to device and within a device depends on control of the polysilicon structure.
One problem that arises in the fabrication of integrated circuits is that a high quality polysilicon is needed to built transistors and devices have suitable performance. Unfortunately the deposition rate of high quality amorphous polysilicon is too low, often on the order of 15 to 20 .ANG. per minute so that the deposition polysilicon layers of suitable thickness, for example 1000 to 5000 .ANG., requires a processing time of 50 minutes to about five hours. This deposition time is too long to fabricate integrated circuits with an effective throughput and a reasonable cost.
What is needed is a polysilicon structure and deposition technique that achieves a suitable deposition rate and fabrication throughput.

Integrated circuit including a graded grain structure for enhanced transistor formation and fabrication method thereof


A porous body containing a silicon component as a starting material of optical element is immersed in a solution containing hydrofluoric acid, taken out from the solution and immersed in a solution containing a metal alkoxide containing a first metal component except silicon or a derivative thereof so that the porous body contains the first metal component in such a concentration gradient that the concentration of the first metal component decreases from a periphery of the porous body toward a center of the porous body. Hydrofluoric acid breaks glass bonds of the porous body, so that the concentration of the first metal component can be securely distributed in a desired gradient. Drying and sintering of the porous body enables producing, for example, a glass having a metal component concentration concavely distributed in its radial direction which is excellent in chromatic aberration suppressing capability. After the immersion in the solution of first metal component, the porous body can be immersed in a solution of second metal component to thereby provide the porous body with a concentration gradient of second metal component.

1. Field of the Invention
The present invention relates to a process for producing a gradient index optical element and a gradient index optical element produced thereby which is suitable for use in optical devices such as a camera, a microscope, an endoscope and an electronic imaging optical system. More particularly, the present invention is concerned with a process for producing a gradient index optical element in which a porous body containing a silicon component is immersed in a solution containing hydrofluoric acid and thereafter in a solution containing a metal alkoxide or derivative thereof and concerned with a gradient index optical element produced thereby.
2. Discussion of Related Art
The gradient index optical element is one whose medium itself has been provided with refractive power by causing the medium to have a refractive index distribution. The gradient index optical element has excellent aberration suppressing capability to thereby enable reducing the number of constituent lenses, so that it is attracting attention as an optical element which is indispensable in next-generation optical systems.
The known gradient index optical elements can be classified as follows, depending on the Abbe's number change and the refractive index change in the radial direction thereof. That is, the gradient index optical element whose refractive index decreases from a glass center to a periphery thereof is designated the gradient index optical element of the positive refractive power type, and the gradient index optical element whose refractive index contrarily increases is designated the gradient index optical element of the negative refractive power type. With respect to the chromatic dispersion accompanying the refractive index change, the chromatic dispersion distribution in which the Abbe's number is decreased with the increase of the refractive index is designated the positive dispersion distribution, the chromatic dispersion distribution in which the Abbe's number is contrarily increased with the increase of the refractive index is designated the negative dispersion distribution and the chromatic dispersion distribution in which the Abbe's number has no substantial change irrespective of the increase of the refractive index is designated the low dispersion distribution. Thus, combinations of the refractive index change and the Abbe's number change give, for example, an optical element of a negative dispersion distribution of the positive refractive power type. The chromatic dispersion distribution in which the refractive index is scarcely changed and the Abbe's number is greatly changed is designated the super dispersion distribution.
In the field of developments of such optical elements, for example, Microoptics News, vol. 9-3, pp. 13-18 (1991), Preprints of papers 127-128 Presented before 1992 Japan Optics Symposium, U.S. Pat. No. 5,166,827 and SPIE, vol. 1780, pp. 456-463 (1992) disclosed that the low or negative dispersion distribution is advantageous in the gradient index optical element of excellent chromatic aberration suppressing capability which is applicable to white light sources. Further, Applied Optics, vol. 25 no. 18, pp. 3351-3355 (1986) described that the gradient index optical element of the negative refractive power type has excellent chromatic aberration suppressing capability. Still further, Japanese Patent Application Laid-Open Specification No. 148405/1994 disclosed the composition realizing the super dispersion distribution. In the production of the above gradient index optical element having excellent chromatic aberration suppressing capability, it is requisite that the concentration of a metal component such as Ti, Nb, Ta or Zr be continuously increased from a glass center toward a periphery thereof, namely, have a concave distribution.
These gradient index optical elements are produced by, for example, the customary sol gel process, ion exchange process or molecular stuffing process. Among these processes, the sol gel process is attracting intense attention because a glass of high aperture ratio can be obtained and a polyvalent metal oxide can be provided with a distribution to thereby enable giving variation to the optical properties of the obtained gradient index optical element.
Japanese Patent Application Laid-Open Specification No. 108626/1992 disclosed a process for producing the gradient index optical element of the negative refractive power type in which a porous body is immersed in a distribution imparting solution and cooled to thereby stop the move of the distribution imparting solution according to the sol gel process. On the other hand, Japanese Patent Application Laid-Open Specification No. 306126/1993 disclosed a process for producing the gradient index optical element of the negative refractive power type in which a metal salt is incorporated in a porous body from its periphery.
Japanese Patent Application Laid-Open Specification No. 55339/1992 disclosed a process comprising immersing a gel containing a first dopant in a suitable leaching solution to thereby provide the first dopant with a distribution, followed by providing a second component with a distribution. Japanese Patent Application Laid-Open Specification No. 292624/1987 described a process for producing SiO.sub.2 --TiO.sub.2 glass in which a porous body is immersed in a Ti-containing solution to thereby cause the porous body to uniformly contain the Ti component. Japanese Patent Application Laid-Open Specification No. 83719/1992 described a process for producing the gradient index optical element of the positive refractive power type in which a wet porous body of SiO.sub.2 --TiO.sub.2 is immersed in a fluorine-containing solution to thereby leach out the Ti component, so that the optical element has a refractive index distribution having a convex profile in the radial direction thereof.
The application of the process of Japanese Patent Application Laid-Open Specification No. 306126/1993 to the production of the gradient index optical element in which a metal component such as Ti, Nb, Ta or Zr having intense influence on the refractive index is provided with a concave distribution in the radial direction of the porous body is difficult because a suitable salt is not available. The terminology "suitable salt" used herein means the salt which can be easily handled, can be dissolved in an available solvent, can easily control chemical reaction and can produce a homogeneous sol when being used as a material of the sol gel process.
The process of Japanese Patent Application Laid-Open Specification No. 108626/1992 has drawbacks in that metal components are precipitated because of substantial changes of the solubilities thereof which occur in accordance with temperature changes, selection of an employed solvent is difficult and further the reproducibility of the resultant refractive index distribution is not good. In the process of Japanese Patent Application Laid-Open Specification No. 55339/1992, the realization of a concave metal concentration distribution is difficult although the first dopant can be easily provided with a convex metal concentration distribution. On the other hand, the use of the process of Japanese Patent Application Laid-Open Specification No. 292624/1987 for reducing the time of immersion in the titanium-containing solution to there-by provide titanium with a concave distribution in the radial direction encounters problems such that not only can only a small proportion of titanium component contribute to the network because of strong Si--O--Si bonds but also part of the titanium component which does not associate with the Si--O--Si bonds aggregates together at the time of sintering of the porous body to thereby cause precipitation of anatase crystals with the result that the obtained optical element is devitrified. The process of Japanese Patent Application Laid-Open Specification No. 83719/1992 has a drawback in that a concave metal concentration distribution cannot be realized although the use of hydrofluoric acid for leaching out the titanium component from the silica titanium gel can naturally provide the titanium with a convex metal concentration distribution.

Process for producing gradient index optical element


Non-volatile memory devices include memory cells therein with reduced cell-to-cell coupling capacitance. These memory cells include floating gate electrodes with open-ended wraparound shapes that operate to reduce the cell-to-cell coupling capacitance in a bit line direction, while still maintaining a high coupling ratio between control and floating gate electrodes within each memory cell.

One class of nonvolatile memory devices includes electrically erasable programmable read only memory (EEPROM), which may be used in many applications including embedded applications and mass storage applications. In typical embedded applications, an EEPROM device may be used to provide code storage in personal computers or mobile phones, for example, where fast random access read times may be required. Typical mass storage applications include memory card applications requiring high capacity and low cost.
One category of EEPROM devices includes NAND-type flash memories, which can provide a low cost and high capacity alternative to other forms of nonvolatile memory. A typical NAND-type flash memory includes a plurality of NAND-type strings therein that are disposed side-by-side in a semiconductor substrate. Each EEPROM cell within a NAND-type string includes a floating gate electrode and a control gate electrode, which is electrically connected to a respective word line. These EEPROM cells may be cells that support a single or a multi-level programmed state. EEPROM cells that support only a single programmed state are typically referred to as single level cells (SLC). In particular, an SLC may support an erased state, which may be treated as a logic 1 storage value, and a programmed state, which may be treated as a logic 0 storage value. The SLC may have a negative threshold voltage (Vth) when erased (e.g., −3V<Vth<−1V) and a positive threshold voltage when programmed (e.g., 1V<Vth<3V).
The state of an EEPROM cell may be detected by performing a read operation on a selected cell. As will be understood by those skilled in the art, a NAND string will operate to discharge a precharged bit line BL when a selected cell is in an erased state and a selected word line voltage (e.g., 0 Volts) is greater than the threshold voltage of the selected cell. However, when a selected cell is in a programmed state, the corresponding NAND string will provide an open circuit to the precharged bit line because the selected word line voltage (e.g., 0 Volts) is less than the threshold voltage of the selected cell and the selected cell remains "off". Other aspects of NAND-type flash memories are disclosed in U.S. application Ser. No. 11/358,648, filed Feb. 21, 2006, and in an article by Jung et al., entitled "A 3.3 Volt Single Power Supply 16-Mb Nonvolatile Virtual DRAM Using a NAND Flash Memory Technology," IEEE Journal of Solid-State Circuits, Vol. 32, No. 11, pp. 1748-1757, November (1997), the disclosures of which are hereby incorporated herein by reference.
Operations to program or erase an EEPROM cell may include the application of a relatively high program or erase voltage to the control electrode or channel region of the EEPROM cell, respectively. As will be understood by those skilled in the art, the magnitude of a program voltage should be sufficient to attract a sufficient number of electrons to a floating gate electrode within the cell and the magnitude of the erase voltage should be sufficient to withdraw a high percentage of accumulated electrons from the floating gate electrode. These operations to attract electrons to the floating gate electrode or withdraw electrons from the floating gate electrode result in a change in a threshold voltage of the EEPROM cell. In particular, operations to program an EEPROM cell may result in an increase in the threshold voltage of the EEPROM cell and operations to erase an EEPROM cell may result in a decrease in the threshold voltage of the EEPROM cell, as described above for both single and multi-level cells.
Unfortunately, as EEPROM devices become more highly integrated on a semiconductor substrate, the parasitic capacitance between floating gate electrodes of closely adjacent EEPROM cells may increase. As illustrated by FIGS. 1A-1C, this parasitic capacitance is directly proportional to the area of overlap between adjacent floating gate electrodes and inversely proportional to the lateral distance between adjacent floating gate electrodes. This lateral distance is typically reduced as the level of device integration increases. In particular, FIG. 1A illustrates an array of NAND-type EEPROM devices, which includes a plurality of floating gate electrodes 19 spaced side-by-side in two dimensions (e.g., row and column directions). These floating gate electrodes 19 are separated from active regions 13 of a semiconductor substrate 11 by tunnel insulating layers 17. These active regions 13 are defined by spaced-apart trench isolation regions 15. The control electrodes of each EEPROM cell within a row are commonly connected to respective word lines 23 (shown as word lines A, B and C). Each floating gate electrode 19 is separated from a corresponding word line by an inter-gate dielectric layer 21. As illustrated by FIGS. 1B-1C, the floating gate electrodes 19 are spaced apart from each other in a bit line direction by source/drain regions 25 and are spaced apart from each other in a word line direction by the trench isolation regions 15. The area of overlap between each floating gate electrode in the bit line direction is equivalent to the product h1W1 and the area of overlap between each floating gate electrode in the word line direction is equivalent to the product h1×W2.
These increases in parasitic capacitance caused by higher device integrated levels can result in a corresponding increase in floating gate interference. If this interference is sufficiently high, then the programming of one EEPROM cell may result in a threshold voltage shift of one or more closely adjacent EEPROM cells in the neighborhood of the EEPROM cell undergoing programming. Such shifts in threshold voltage can reduce memory device reliability by causing bit errors to occur during data reading operations. These and other consequences of increased parasitic capacitance between floating gate electrodes are described in an article by Jae-Duk Lee et al. entitled "Effects of Floating-Gate Interference on NAND Flash Memory Cell Operation," IEEE Electron Device Letters, Vol. 23, No. 5, pp. 264-266, May (2002).

Non-volatile memory devices with wraparound-shaped floating gate electrodes and methods of forming same


A color photographing device is equipped with a light-receiving section having a red pixel selectively receiving red light and outputting a red pixel signal and a green pixel selectively receiving green light and outputting a green pixel signal. The color photographing device is further equipped with an optical filter disposed on the side with a light-receiving surface of the light-receiving section. The optical filter substantially equalizes the signal level of the red pixel signal and the signal level of the green pixel signal when achromatic color illuminated by a solar light source in the daytime is photographed. Therefore, a white balance gain Wr at about 5000K can be lowered as compared with a conventional color photographing device. Accordingly, reduction of color noises and enhancement of gradation can be expected.

1. Field of the Invention
The present invention relates to a color photographing device such as an electronic camera, a digital video camera or the like. Specifically, the present invention relates to a white balance adjustment carried out by a color photographing device.
2. Description of the Related Art
In general, color temperature of a light source for illuminating an object is different among photographing places. Colors reproduced as an image reflect colors of the object itself and colors of the light source for illuminating the object. Therefore, white balance is adjusted in the color photographing device so that a white object is reproduced to be white (for example, see Japanese Unexamined Patent Publication No. 2000-92509 and Japanese Unexamined Patent Publication No. Hei 7-193826).
For example, in a color photographing device in which a red pixel signal R, a green pixel signal G and a blue pixel signal B are output by an image sensor, white balance is adjusted so that the signal levels of R, G and B are equal to one another when achromatic color is photographed. Specifically, the color temperature of a light source is first estimated. Then, R and B are multiplied by gains Wr and Wb, respectively, for white balance processing (hereinafter referred to as "white balance gains") which correspond to the color temperature.
FIG. 1 shows an example of a spectral sensitivity characteristic of a conventional image sensor, which is normalized on the basis of the peak value of the sensitivity of green pixels, and FIG. 2 shows a white balance gain characteristic to the image sensor having the spectral sensitivity characteristic shown in FIG. 1. As is apparent from FIG. 2, the conventional image sensor has a spectral sensitivity characteristic that the ratio of the signal levels of R, G and B are equal to about 0.45:1:0.55 when achromatic color illuminated by a light source having color temperature of 5000K is photographed. The following two reasons can be given as a part of the reasons that the spectral sensitivity characteristic of the image sensor has been set as described above.
First, G contains a larger mount of brightness information than R or B. Therefore, when the signal level of G is varied, the brightness of an overall image is varied.
Accordingly, when white balance is adjusted, the white balance gain Wg to G must be set to 1.
Second, the white balance gains Wr and Wb are normally required to be equal to 1 or more. This is because if there is any color temperature at which the white balance gains Wr and Wb are set at less than 1, the highlight becomes colored at the color temperature.
More specifically, if Wr, Wb>1, pixel signals R, G, and B are held saturated, and thus the highlight remains white. However, if white balance is adjusted with Wr being smaller than 1, G and B remain at their maximum values, but R is set to be smaller than the maximum value thereof. Accordingly, the white of the highlight is reproduced to be slightly blue-green.
In the conventional color photographing device, as shown in FIG. 2, about double the white balance gain was applied to both Wr and Wb when color temperature was around 5000K (color temperature at which photographing is considered to be most frequently carried out). However, the higher the Wr and Wb are, the more remarkable the troubles are, such as increased noises of R and B and discontinuity of gradation. Particularly, color noises can be remarkable at dark portions of an image.


A network searching method adapted to a mobile electronic device in a no service state is provided. In the method, a first timer is activated. A network searching operation is performed. Whether an available network is found is determined. If the available network is not found, whether a time count of the first timer is smaller than a network searching active interval is determined. If the time count is not smaller than the network searching active interval, a second timer is activated. Before a network searching inactive interval set up by the second timer expires, the mobile electronic device is controlled to remain in a power save mode. If the time count is smaller than the network searching active interval, a third timer is activated. When a sleep interval set up by the third timer expires, the mobile electronic device is controlled to perform the network searching operation again.

1. Field of the Invention
The invention generally relates to a network searching method adapted to a mobile electronic device, and more particularly, to a network searching method adapted to a mobile electronic device in a no service state.
2. Description of Related Art
Generally, when there is no service available, a mobile electronic device (for example, a cell phone or a smart phone) keeps performing a network searching operation until it finds and connects to an available network. As a result, the battery power of the mobile electronic device is quickly consumed. For example, one may leave his or her cell phone in the car and park the car in the basement. As a result, the cell phone remains in a no service state for a very long time therefore cannot register with any available network. Based on the existing technique, the cell phone keeps searching for an available network at regular intervals until the battery power is exhausted.
FIG. 1 is a networking searching timing diagram of a conventional mobile electronic device in a no service state. Referring to FIG. 1, the abscissa represents time in unit of second. The period from time t1 to time t2 is referred to as a search interval I1. During the search interval I1, the mobile electronic device performs a network searching operation. In the present embodiment, the search interval I1 is, for example, 5 seconds. The period from time t2 to time t3 is referred to as a sleep interval I2. If the mobile electronic device does not find any available network, it stops searching for any network during the sleep interval. In the present embodiment, the sleep interval I2 is, for example, 30 seconds. The sleep interval is followed by another search interval, during which the mobile electronic device performs another network searching operation. If the mobile electronic device cannot find any available network, it repeatedly performs and stops the network searching operation until an available network is found or the battery power of the mobile electronic device is exhausted.
In another existing network searching method, the sleep interval is set to a variable value, and the longer the mobile electronic device remains in the no service state, the longer the sleep interval is. Such a design contradicts the communication protocol compatibility test specified by the 3rd Generation Partnership Project (3GPP). Besides, when the mobile electronic device moves to a valid network coverage area, it may not be able to resume the network searching operation due to the overlong sleep interval. As a result, an unpleasant experience is brought to the end user.

Network searching method for reducing power consumption and mobile electronic device using the same


Provided are a method and apparatus for determining whether backlight exists. The method according to an embodiment of the present invention includes calculating scattering degrees of luminance values of pixels included in each of images which represent the same photographic subject and have different brightness levels from each other; and determining whether backlight exists on the photographic subject in consideration of the calculated scattering degrees.

1. Field of the Invention
The present invention relates to a photographing device such as a digital camera, and more particularly, to a method and apparatus for determining whether backlight exists on a photographic subject.
2. Description of the Related Art
When backlight exists on a photographic subject, if the backlight is not considered, the photographic subject is photographed so as to be excessively dark. Thus, when backlight exists on a photographic subject, a photographing device such as a digital camera recognizes the backlight and performs a series of processes before the photographic subject is photographed in order to obtain a clear image of the photographic subject even when the backlight exists. Turning flash on and increasing an exposure value (EV) of the photographing device are examples of the processes.
However, a conventional photographing device may wrongly determine that backlight exists on a photographic subject, for example, when the photographic subject is originally very dark or when the photographic subject is disposed in very bright surroundings. Thus, the conventional photographing device may not clearly photograph the photographic subject on which backlight does not actually exist, by performing the above processes before the photographic subject is photographed.

Method and apparatus for determining whether backlight exists


A scanning projection exposure apparatus having a projection optical system (11), for serially transferring a pattern on a reticle (7) onto a wafer (12). The exposure apparatus control the position and/or the tilt angle of the wafer (12) such that the surface of the wafer (12) may be continuously adjusted during the scanning exposure operation so as to be coincident with an image plane of the projection optical system (11), with a high tracking accuracy, even when the image plane of the projection optical system (11) tends to vary during the scanning exposure operation. An image of that portion of the pattern on the reticle (7) which is confined in an illumination area (8) is formed in a plane through the projection optical system. This plane is used as a first reference plane (62). Parameters of the first reference plane (62) such as the tilt angle .theta..sub.p are determined by measurement. An image plane is defined by conjugate images (formed on the wafer side) of the points passing the center of the illumination area (8) when the reticle (7) is moved for scanning in the X-direction. This image plane is used as a second reference plane (65). The tilt angle .THETA..sub.x of the second reference plane (65) is determined by measurement. When the scanning exposure operation is performed, the tilt angle of the illumination field (13) of the wafer (12) is made coincident with that of the first reference plane (62), and the focusing position of the wafer (12) is made coincident with that of the second reference plane (65).

1. Field of the Invention
The present invention relates to a projection exposure apparatus for use in photolithographic processes or fabricating semiconductor devices (such as LSIs), imaging devices (such as CCDs), liquid crystal displays (LCDs), thin film magnetic heads and others. More particularly, the present invention relates to a scanning exposure type of projection exposure apparatus, such as of a so-called step-and-scan type, in which a mask and a photosensitized substrate are moved for scanning in synchronism with each other and relative to an exposure optical system, so as to serially transfer a pattern formed on the mask onto the photosensitized substrate.
2. Description of the Related Art
The photolithography technique is commonly used in fabrication of semiconductor devices and the like. For this technique, there are used step-and-repeat type of projection exposure apparatuses (such as steppers) in which a pattern formed on a reticle (serving as a mask) is projected through a projection optical system onto each of shot areas defined on a photoresist-coated wafer (or glass plate, etc.). More recently, as larger and larger chips of semiconductor devices are being fabricated, it has become desired to make a projection exposure having a much larger pattern onto a wafer. In order to meet this desire, there has been developed a scanning exposure type of projection exposure apparatus in which a reticle and a wafer are moved for scanning in synchronism with each other and relative to a projection optical system, so that a shot area having a larger extent than the effective exposure field of the projection optical system may be exposed.
One of the known types of projection exposure apparatuses using the scanning exposure technique is the aligner, in which the entire region of the pattern on one reticle is serially projected onto the entire region of the surface of one photosensitized substrate by using a 1:1 projection optical system. More recently, there has been developed a step-and-scan type of projection exposure apparatus, in which each of shot areas on a wafer is exposed by demagnification projection scanning exposure and the exposure site is moved from one shot area to another by stepping the wafer.
In general, the projection exposure apparatus uses a projection optical system which has a large numerical aperture (NA) and thus a very shallow focal depth, so that a certain type of mechanism must be provided for keeping the surface of the wafer coincident with the image plane of the projection optical system so as to enable transfer of a fine circuit pattern with a high resolution.
Therefore, in a conventional one-shot exposure type of projection exposure apparatus, a tilt sensor (or leveling sensor) is provided to measure a tilt angle of the surface of the wafer relative to the guide plane (or slide plane) of the wafer stage. Further, a tilt angle of the image plane of the projection optical system relative to that guide plane is also measured and stored as preparatory data. Then, the tilt angle of the surface of the wafer is controlled by servo-control technique such that the measured value supplied by the tilt sensor may converge to the tilt angle of the image plane and thereby the surface of the wafer is made parallel to the image plane. In addition, by performing such control of the tilt angle (auto-leveling control) together with the so-called auto-focusing control for causing the height of the surface (focusing position) of the wafer to be coincident with the image plane of the projection optical system, the entire region of each shot area on the wafer is kept falling within the range of focal depth about the image plane. So far, the scanning exposure type of projection exposure apparatus also uses essentially the same control technique as that for the one-shot exposure type of projection exposure apparatus as described above, in order to cause the surface of the wafer to be coincident with the image plane.
In the scanning exposure technique, an image of a portion of the pattern on the reticle is projected through the projection optical system onto the wafer and within a slit-like projection exposure area on the wafer (this area is referred to as the "illumination field" hereinafter). In contrast, the area on the wafer within which the entire pattern on the reticle is serially projected, and thus which is larger than the illumination field, is referred to as the "exposure field" (corresponding to a shot area).
In a typical conventional scanning exposure apparatus, and in particular in the demagnification projection step-and-scan type of projection exposure apparatus, the reticle and the wafer are moved for scanning independently of each other and relative to the projection optical system, so that the slide plane of the reticle and that of the wafer are established independently. Further, because it is impossible to achieve the perfect parallelism between the slide plane of the reticle and the pattern surface of the reticle, the level (height) of the image plane of the projection optical system (i.e., the plane in which the image of the pattern on the reticle is formed through the projection optical system) may gradually vary as the position of the reticle in the scanning direction varies. Such gradual variation of the level of the image plane may cause a tracking error if the response speed of the auto-focusing control is relatively low, resulting in that a portion of the surface of the wafer within the exposure field (shot area) may not fall within the range of focal depth relative to the image plane.
Because the auto-focusing (AF) sensor and the tilt sensor are used for detecting the focusing position and the tilt angle, respectively, of that portion of the surface of the wafer which is confined within the projection exposure area (or the slit-like illumination field in the case of the scanning exposure type), the detection areas of these sensors are generally confined within the projection exposure area (or the slit-like illumination field). For this reason, in a conventional control sequence, the focusing and leveling control is performed only during the time period when an exposure area on the wafer is actually exposed. Thus, during the time period when the exposure site moves from one projection exposure area to another, the focusing and leveling control is made inoperative and the positions of the Z-stage and the tilt-stage are kept fixed. Then, when the positioning of the wafer for the new projection exposure area (or the new scanning start position) has been made, the focusing and leveling control is restarted. This control sequence is utilized because the whole path of the movement of the exposure site from one projection exposure area (or the scanning start position) to the next may not necessarily be confined within the regions which are detectable, but may be within the regions which are not detectable, so that it is difficult to continue the focusing leveling control. In the case where the focusing and leveling control is made inoperative during the movement to the next location, the focusing position of the surface of the wafer may significantly vary after such movement if the wafer surface is inclined relative to the guide plane of the wafer stage. This results in large initial adjustments (which equal the focusing error, that is, an amount of defocusing and the tilt angle error) required when the focusing and levelling control restarts at the next illumination field to be exposed, thus a longer settling time (adjustment time) is required for these errors to settle within allowable ranges. This results in a drawback that the throughput of the exposure process (the number of wafers that can be exposed per unit of time) is reduced.
In particular, in a typical step-and-scan type of projection exposure apparatus, the focusing and levelling control of the wafer surface is continuously performed during the scanning exposure on each exposure area while the wafer is moved for scanning. Therefore, if there is on the surface of the wafer a region with a groove-like structure (such as so-called street lines for indicating the border between adjacent semiconductor chips sites on a wafer), which is inappropriate for the region from which measurements are derived for the focusing and levelling control, then the focusing and levelling control may be disturbed, resulting in a lower tracking accuracy as well as a longer settling time.

Projecting exposure apparatus and method of exposing a circuit substrate


A system and method is provided to reduce the occurrence of engine knock for engines that utilize a dual-fuel fumigation system. Typically, dual fuel systems inject a gaseous-fuel flow into the air intake stream of a diesel engine. This results in more complete combustion within the engine as well as reduced diesel fuel usage. Such dual fuel systems are susceptible to engine knocking due to premature detonation of the gaseous fuel air intake mixture that is often caused by sudden changes to the operating conditions of the engine. The present system utilizes a knock sensor to identify early stages of such engine knocking. To eliminate such engine knocking conditions, the system temporarily interrupts the gaseous fuel flow to resume operation in full diesel mode. The gaseous fuel flow is then reestablished based on the present operating conditions of the engine.

Due to the high thermal efficiency achieved by compression-ignited engines (e.g., in comparison with spark-ignited engines), such engines are commonly utilized in industrial applications. Further, due to increasing fuel costs, such engines are also gaining popularity in the passenger vehicle and light truck markets. The high efficiency of compression-ignited engines, such as diesel engines, is due in part to the ability to use higher compression ratios than spark-ignited engines (i.e., gasoline engines) as well as the ability to control power output without a throttle. In the latter regard, the lack of a throttle eliminates throttling losses of premixed charges typical in spark-ignited engines thereby resulting in significantly higher efficiency at part load. However, compression-ignited engines and diesel engines in particular typically cannot achieve the low oxides of nitrogen (NOx) and particulate emission levels that are possible with spark-ignited engines.
Diesel engines typically inject diesel fuel into the engine's combustion chamber when that chamber's piston is near the end of the compression stroke. The high pressure present in the chamber ignites the diesel fuel. Due to the injection mixture of diesel fuel and compressed intake air within the combustion chamber, a large fraction of the fuel exists at a very fuel-rich equivalence ratio. That is, the fuel and air in the combustion chamber are not necessarily a homogenous mixture. This may result in incomplete combustion of the diesel fuel, which tends to result in high particulate emissions. Furthermore, the fuel-rich equivalence ratio can also lead to high flame temperatures in the combustion process, which results in increased NOx emissions. As tougher environmental standards are being enacted for all internal combustion engines, users of diesel engines are looking for ways to lower emissions. One solution is to reduce the amount of diesel injected into the combustion chamber, which reduces the equivalence ratio and works to reduce particulate and NOx emissions. Such a reduction in injected diesel, however, reduces engine power.
Utilization of gaseous-fuels with diesel engines provides for more complete combustion of any diesel fuel consumed, can enhance fuel economy, and typically results in lower engine emissions. That is, in order to reduce particulate and NOx emissions levels from diesel engines and/or to increase fuel economy, such engines may be partially or completely converted for use with gaseous-fuels such as, compressed natural gas (CNG), liquid natural fuels (LNG) such as ethanol, and liquid or liquefied petroleum gas (LPG), such as propane. However, such gaseous-fuels typically do not alone have the centane value required to allow for their ignition through compression. Accordingly, diesel engines must be modified to use such fuels.
Methods for converting a diesel engine to consume gaseous-fuels typically fall into three categories. The first is to convert the engine to a spark-ignited engine; a second is to convert the engine to allow for the direct injection of gaseous-fuels into the combustion chamber with injected diesel; and a third is a dual-fuel technology, in which the gaseous-fuel is mixed with all or a portion of the intake air of the engine. As will be appreciated, the second and third methods utilize injected diesel (i.e., pilot diesel) to ignite the gaseous-fuel. In this regard, the combustion of the gaseous-fuel results in more complete combustion of the injected diesel. Furthermore, as the gaseous-fuel allows the engine to produce additional power less diesel is injected into the engine.
Conversion to a spark-ignition system and/or a direct gaseous-fuel injection system for utilizing gaseous-fuels with a diesel engine each typically require substantial modification to the diesel engine. Such modifications may include replacement of cylinder heads, pistons, fuel injection system and/or duplication of many engine components (e.g., injection systems). Accordingly, these systems are typically expensive and oftentimes unreliable. On the other hand, dual-fuel systems require little modification to existing engines.
Dual-fuel operation where gaseous-fuels are mixed with intake air prior to the introduction of that air-fuel mixture into the cylinders of the engine is known in the art as fumigation. That is, the mixture of gaseous-fuel and intake air is introduced into each cylinder of the engine during the intake stroke. During the compression stroke of the cylinder piston, the pressure and temperature of the mixture are increased. Near the end of the compression stroke, a small quantity of pilot diesel fuel from the engine's existing diesel fuel injection system is injected into the cylinder. The pilot diesel ignites due to compression and in turn ignites the mixture of gaseous-fuel and intake air. As will be appreciated, such fumigation systems may be retrofit onto existing diesel engines with little or no modification of the existing engine. Furthermore, engines using such fumigation systems may typically be operated in a dual-fuel mode or in a strictly diesel mode (e.g., when gaseous-fuel is not available).