The invention is in the field of engine building technology and may be used in space technology or aviation. Liquid-propellant rockets with Laval nozzles are well known, and they have the following insufficiencies: (1) high fuel consumption rates, which lead to increased dimensions and engine weight and boosters; (2) a relatively low combustion efficiency, because the low mass of the combustion products are emitted into the environment; (3) the large length of the de Laval nozzles with increased expansion ratios increase the dimensions and the engine weight; (4) use of high temperature rocket propellants—combustion products—in the camera and de Laval nozzle. These insufficiencies suppress using liquid-propellant rockets in space technology. The goal of the invention is decreasing the influence of these insufficiencies and obtaining an engine with improved efficiency. The goal is achieved with the creation of an engine with the subsonic discharge of combustion products and the creation of a simple nozzle construction.

Field of Invention
The disclosed subject matter is in the field of engine building technology for space technology or aviation.
Background of the Invention
Generally, known engines with de Laval nozzles are widely used in domestic and foreign rockets of various classes. Surveys and accounts of these engines have been provided in a number of literary sources, such as: "Foreign Rocket Engines," Reference Guide, Central Institute of Aviation Motors 1967; "Liquid-Propellant Rockets Using Oxygen and Kerosene," Survey No. 195, GONTI-3, 1964; "Foreign Military Survey," Nos. 5 and 6, 2001; Writings of the Scientific Development and Production Center EnergoMash, Vol. 21 (Moscow 2003); E. B. Volkov et al., Liquid-Propellant Rocket (Moscow: Voenizdat, 1970).
An insufficiency of the method for creating thrust in the above-listed analogues is the relatively low combustion efficiency, which leads to large sizes and engine weight. The method for creating thrust is characteristic for all types of liquid-propellant rockets and is set forth in detail in the book written by V. E. Alemasov, et al., Theory of Rockets (Moscow: Mashinostroeniye, 1969). Its essence is as follows. The flow of the liquid propellant has a plane-parallel movement in the nozzle cavity axially and races out of the chamber to the nozzle exit, passing through critical speed. The primary portion of the thrust in this case is determined by the expenditure and speed of the intersection at the nozzle exit.
An additional portion of the thrust is determined by the area of the exit and pressure on the exit. It is insignificant, comprising only approximately 3.7% of the primary portion of the thrust of the engine in a vacuum. The following are its insufficiencies: (1) high fuel consumption rates increase the sizes and masses of the constructions; (2) a relatively low combustion efficiency, because the large mass of the combustion products at a high temperature are emitted into the environment; (3) utilizing high nozzle expansion rations generated by high exhaust velocities, which lead to an increase in the length and mass of the nozzle and the axial dimensions of the engine; (4) using high temperature rocket propellants—combustion products in the chamber and nozzle.


Apparatus and methods for quadrature clock signal generation are provided. In certain implementations, an apparatus includes an invertible sine shaping filter configured to receive an in-phase clock signal, a quadrature-phase clock signal, and an inversion control signal. The invertible sine-shaping filter is further configured to filter the in-phase and quadrature-phase clock signals to generate sinusoidal in-phase and quadrature-phase clock signals. The invertible sine-shaping filter is further configured to selectively invert one or both of the in-phase and quadrature-phase clock signals based on an inversion control signal. The apparatus further includes a phase interpolator configured to generate an interpolated clock signal based on a weighted sum of the selectively inverted sinusoidal in-phase clock signal and the quadrature-phase sinusoidal clock signal. The in-phase clock signal and the quadrature-phase clock signal have a quadrature-phase relationship.

1. Field
Embodiments of the invention relate to electronic devices, and more particularly, to sine-shaping filters and phase interpolators.
2. Description of the Related Technology
Clock and data recovery (CDR) systems can be used in a variety of applications for recovering data from a high-speed serial data stream. CDR systems can be used in, for example, telecommunications systems, optical networks, and chip-to-chip communication.
A CDR system can use a sampling clock signal to capture samples from the serial data stream. The sampling clock signal can be generated in a variety of ways. For example, a CDR system can include a frequency synthesizer for generating a high speed clock signal having a frequency that is a multiple of a reference clock signal, and the CDR system can generate quadrature square wave clock signals from the high speed clock signal by using a quadrature divider. The quadrature square wave clock signals can be filtered to generate sine and cosine clock signals, which can be used to generate the sampling clock signal by weighted-based phase interpolation.
In certain applications, using a clock synthesizer and a quadrature divider to generate a sampling clock signal can be a practical method of quadrature clock signal generation. However, as data rates of CDR systems increase, the synthesizer and/or the quadrature divider can become more difficult to design, consume a relatively large amount of power, and/or occupy a relatively large die area. Additionally, for certain applications, such as radio transceiver applications, the high speed clock signal can generate undesirable coupling, pulling, and/or other forms of interference.
Similarly, in certain applications, phase interpolation can include both positive and negative weightings for each of the in-phase and quadrature-phases. As the number of weightings increases, the phase interpolator can become more difficult to design, consume a relatively large amount of power, present a relatively large load to input drivers, and/or occupy a relatively large die area. For example, interpolation buffers can consume a significant leakage power, even when inactive.
There is a need for CDR systems having improved performance. Additionally, there is need for improved systems and methods for quadrature clock signal generation.

Apparatus and methods for invertible sine-shaping for phase interpolation


An optical disk includes a first area on which user information is recorded, and a second area in which a plurality of marks radially extending are arranged in a track direction in the optical disk. Information about the reflectance of the optical disk is recorded in the second area. It is intended to optimize the amplification factor of the reproduced signal on the basis of the information about the reflectance of the optical disk in the second area. Control data and user data can be reproduced quickly and highly reliably without depending on the relationship between the reflectances of a recording area and a non-recorded area of the optical disk.

1. Field of the Invention
The present invention relates to an optical disk, a method for producing the same, and a recording and reproducing apparatus. In particular, the present invention relates to an optical disk which stably reproduces information recorded on optical disks having different reflectances, a method for producing the same, and a recording and reproducing apparatus.
2. Description of the Related Art
DVD, which has appeared in recent years, has a lineup including, for example, not only information read-only DVD-ROM and DVD-Video but also information recordable DVD-R and information rewritable DVD-RAM and DVD-RW. Therefore, the DVD market is rapidly expanded not only as the screen image-recording and reproducing medium which substitutes VTR but also as the large capacity medium for computers. Recently, the digital broadcast has come into widespread use, which simultaneously increases the demand for any medium capable of responding to the high detailed image and the long time recording and the demand for any large capacity storage medium capable of responding to the digital data increasing day after day.
A variety of techniques have been hitherto suggested in the field of the optical disk in order to realize the high density. Those having been suggested include, for example, a method in which the recording mark is made fine and minute by using the blue laser having a shorter wavelength (λ=405 nm) and a method in which the high density is realized by recording information on both of the land and the groove of the optical disk. In view of the format, various optical disks have been also suggested, in which not only the data-recording section but also the header section structure to store, for example, the address information is contrived. For example, in the case of iD-photo, the guide groove is deflected in the radial direction of the track to record information about the header section on only one side of the recording track, and thus the format efficiency is enhanced without longly cutting the recording track.
The phase-change recording system, which is adopted, for example, for DVD-RAM and DVD-RW, is generally used in relation to the technique of the information rewritable optical disk. In the case of the optical disk based on the phase-change recording system, a phase-change material is used for a recording layer. Basically, pieces of information of "0" and "1" are recorded to correspond to the crystalline state (non-recorded state) and the amorphous state (recorded state) of the phase-change material respectively. The refractive index differs between areas in the crystalline state and the amorphous state formed in the recording layer. Therefore, for example, the refractive indexes and the thicknesses of the respective layers for constructing the optical disk are designed so that the difference in reflectance is maximized between the portion changed into the crystalline state and the portion changed into the amorphous state. In the case of the optical disk based on the phase-change recording system, the light beam is radiated onto the crystallized portion and the amorphous portion to detect the difference in the reflected light amount between the respective portions of the optical disk so that "0" and "1", which are recorded in the recording layer, are detected.
In order that the amorphous state is realized at a predetermined position of the recording layer of the optical disk based on the phase-change recording system (usually, this operation is referred to as "recording"), the light beam having a relatively high power is radiated so that the temperature of the irradiated portion of the recording layer is raised to a temperature which is not less than the melting point of the recording layer material. On the other hand, in order to effect the crystallization at a predetermined position of the recording layer (usually, this operation is referred to as "erasing"), the light beam having a relatively low power is radiated so that the temperature of the irradiated portion of the recording layer is raised to a temperature which is not more than the melting point of the recording layer material and which is in the vicinity of the crystallization temperature. As described above, in the case of the optical disk based on the phase-change recording system, the predetermined portion in the recording layer can be reversibly changed between the amorphous state and the crystalline state by regulating the radiation power of the light beam to be radiated onto the recording layer.
In the case of the conventional optical disk based on the phase-change recording system, it has been tried to improve the various characteristics of the optical disk by not only increasing the difference in the reflectance between the amorphous state and the crystalline state in the recording layer but also by adjusting the relationship of relative magnitude between the reflectances of the both states. For example, in the case of ordinary DVD-RAM and DVD-RW, the disk is designed so that the reflectance is high at the portion in the crystalline state corresponding to the non-recorded state, and the reflectance is low at the portion in the amorphous state corresponding to the recorded state. Therefore, in the case of the optical disk as described above, the following advantage is obtained, because the address information is recorded in the area in the non-recorded state. That is, the address information is obtained at high S/N, and the reliability of the address information reproduction is improved. Further, in the case of the optical disk as described above, the following advantage is obtained, because the focus servo signal and the tracking servo signal are also obtained from the area in the non-recorded state. That is, it is possible to obtain the tracking servo signal and the focus servo signal having the sufficient intensities, and it is possible to perform, for example, the tracking control in a stable manner.
On the other hand, in relation to the technique of the write-once optical disk capable of recording information only once, a method is generally used, in which a recording layer is formed by using a material containing an organic dye as adopted, for example, for DVD-R. When information is recorded in the recording layer containing the organic dye, the recording mark is formed in the recording layer by causing, for example, at least one of the change of the optical parameter of the organic dye in the recording layer, the deformation of the recording layer as well as the reflective layer and the substrate disposed close to the recording layer, and the gap generated in the recording layer or at the recording layer interface by radiating the light beam having a relatively high power. In the case of DVD-R, the setting is made such that the reflectance is high in the non-recorded state and the reflectance is low in the recorded state, in the same manner as in DVD-RAM and DVD-RW. Therefore, DVD-R is advantageous in that the address information is obtained at high S/N, and the reliability is improved when the address information is reproduced. Further, the focus servo signal and the tracking servo signal are also obtained from the area in the non-recorded state. Therefore, DVD-R is advantageous in that it is possible to obtain the tracking servo signal and the focus servo signal having the sufficient intensities, and it is possible to perform, for example, the control of the tracking in a stable manner.
In this specification, the optical disk, which has the following feature like the conventional DVD-RAM, DVD-RW, and DVD-R, is referred to as "High to Low" disk or simply "HL" disk. That is, when information is recorded by radiating the light beam, the reflectance of the portion irradiated with the light beam (portion in the recorded state) is changed from the high value (high level) to the low value (low level). In general, the HL disk based on the phase-change recording system has a structure including at least a protective layer composed of a transmissive dielectric, a phase-change recording layer, an intermediate layer composed of a transmissive dielectric, and a heat-diffusing layer composed of metal (having a function of a reflective layer as well) which are disposed in this order from the light beam incoming side. Further, the HL disk, which is based on the use of a recording layer containing an organic dye, generally has a structure including at least a recording layer containing an organic dye and a heat-diffusing layer composed of metal (having a function of a reflective layer as well) which are disposed in this order from the light beam incoming side.
In relation to the conventional optical disk based on the phase-change recording system, an optical disk has been also suggested, which is designed such that the reflectance is low in the area in the crystalline state corresponding to the non-recorded state in the recording layer of the optical disk, and the reflectance is high in the area in the amorphous state corresponding to the recorded state (see, for example, Japanese Patent No. 2512087, pp. 4-6, FIG. 1). The optical disk, which is disclosed in Japanese Patent No. 2512087, is advantageous in that old information is erased at a larger ratio when new information is overwritten on the old information.
On the other hand, the optical disk (hereinafter referred to as "organic dye type optical disk"), which is based on the use of the recording layer containing the organic dye, can be also designed such that the reflectance is low in the area in the non-recorded area, and the reflectance is high in the area corresponding to the recorded state. Specifically, the recording mark is formed by causing the change of the optical parameter of the organic dye in the recording layer, while extremely avoiding the deformation of the recording layer as well as the substrate and the reflective layer and the gap generated in the recording layer or at the recording layer interface when the recording mark is formed as described above. Accordingly, the reflectance can be made low in the area in the non-recorded state, and the reflectance can be made high in the area corresponding to the recorded state. The optical disk as described above is advantageous in that the recording sensitivity is improved, because the reflectance is low in the non-recorded area.
In this specification, the optical disk, which has the following feature like the optical disk disclosed in Japanese Patent No. 2512087, is referred to as "Low to High" disk or simply "LH" disk. That is, when information is recorded by radiating the light beam, the reflectance of the portion irradiated with the light beam (portion in the recorded state) is changed from the low value (low level) to the high value (high level). The LH disk, which is based on the phase-change recording system, has a structure as represented by multilayer films including, for example, a recording layer/dielectric layer, a recording layer/metal reflective layer, and a dielectric layer/recording layer/dielectric layer/metal reflective layer. The interference effect is utilized between the films for constructing the multilayer film. Accordingly, the reflectance is low in the area in the crystalline state corresponding to the non-recorded state, and the reflectance is high in the area in the amorphous state corresponding to the recorded state.
Conventionally, an LH disk based on the phase-change recording system has been also suggested (see, for example, Proc. SPIE, vol. 3401, p. 103, 1998), which has a multilayer film structure comprising ZnS—SiO2/SiO2/ZnS—SiO2/Ge2Sb2Te5/ZnS—SiO2/Al alloy. Also in the case of the LH disk, the interference effect is utilized between the films for constructing the multilayer film so that the reflectance is low in the area in the crystalline state corresponding to the non-recorded state, and the reflectance is high in the area in the amorphous state corresponding to the recorded state.
As described above, both of the HL disk and the LH disk have been hitherto investigated in the field of the optical disk based on the phase-change recording system and in the field of the organic dye type optical disk. When each of the optical disks is installed to a conventional recording and reproducing apparatus to record and reproduce information, the following problems arise due to the difference in the film structure. (1) The reflectance in the non-recorded state (crystalline state in the case of the phase-change type) differs between the HL disk and the LH disk. (2) The relationship between the reflectance in the non-recorded state and the average reflectance after the information recording differs between the HL disk and the LH disk. That is, the values of the reflectances in the areas in the non-recorded state and the recorded state and the relationship of relative magnitude therebetween differ depending on whether the optical disk is either the HL disk or the LH disk. Therefore, the level of the reproduced signal to be obtained differs as well. Therefore, a problem arises such that it is impossible to reproduce information stably and highly reliably from both of the HL disk and the LH disk by using any identical recording and reproducing apparatus.
For example, the following method may be conceived in order to solve the problem as described above. That is, any information, which indicates that the optical disk installed to the recording and reproducing apparatus is either the HL disk or the LH disk (hereinafter referred to as "type of the optical disk" as well), is recorded in a control data area for storing the physical format information about the optical disk. The gain is optimally adjusted on the basis of the information, and then the user information or the like is reproduced.
In general, the control data of the optical disk is formed by emboss pits. The control data area and the user data area are formed approximately adjacently to one another. Therefore, in the case of the optical disk based on the phase-change recording system and the optical disk of the organic dye type, for example, the phase-change film, the protective film, and the organic dye film are formed not only in the user data area but also in the control data area respectively. In the case of the conventional optical disks as described above, even when the information concerning the type of the optical disk is recorded in the control data area, the reflectance of the control data area is also changed depending on the type of the optical disk. Therefore, if the gain is not adjusted, it is impossible to accurately reproduce not only the control data but also the information concerning the type of the optical disk. Therefore, in the case of the optical disk on which the information concerning the type of the optical disk is recorded in the control data area, it is necessary that the information concerning the type of the optical disk and the control data are reproduced while adjusting the gain of the reproduced signal depending on the type of the optical disk. Therefore, a problem arises such that the gain adjustment requires a long period of time, and it is impossible to quickly reproduce the control data and the user data. However, at present, there is no method for solving this problem. It is also impossible to find any method for optimizing the gain depending on the type of the optical disk (HL disk or LH disk).

Optical disk with a plurality of radially extending marks for recording reflectance data of the optical disk


The present invention relates an isolated human Site-1 Protease promoter region. The invention also relates to screening methods for agents decreasing the expression of Site-1 protease and thereby being potentially useful for the treatment of medical conditions related to obesity and/or diabetes.

The present invention relates an isolated human Site-1 Protease promoter region. The invention also relates to screening methods for agents decreasing the expression of Site-1 protease and thereby being potentially useful for the treatment of medical conditions related to obesity and/or diabetes.
Sterol Regulatory Element-Binding Proteins (SREBPs)
The integrity of cell membranes is maintained by a balance between the amount of cholesterol and the amounts of unsaturated and saturated fatty acids in phospholipids. This balance is partly maintained by membrane-bound transcription factors called Sterol Regulatory Element-Binding Proteins (SREBPs; for reviews, see Brown and Goldstein (1997) Cell 89, 331-340; Brown and Goldstein (1999) Proc. Natl. Acad. Sci. U.S.A. 96, 11041-11048) that activate genes encoding enzymes of cholesterol and fatty acid biosynthesis. To enhance transcription, the active NH2-terminal domains of SREBPs are released from endoplasmic reticulum membranes by two sequential cleavages. The first is catalyzed by Site-1 protease (S1P), a membrane-bound subtilisin-related serine protease that cleaves the hydrophilic loop of SREBP that projects into the endoplasmic reticulum lumen. The second cleavage, at Site-2, requires the action of S2P, a hydrophobic protein that appears to be a zinc metalloprotease. These regulated proteolytic cleavage reactions are ultimately responsible for controlling the level of cholesterol in membranes, cells, and blood.
Three isoforms of SREBPs have been identified. SREBP-1a and SREBP-1c are encoded by a single gene and differ in their N-terminal acid transcription activation domains. The N-terminus of SREBP-1a is longer and includes additional acidic amino acids, consistent with the observation that it is a more powerful transcription factor (Pai et al. (1998) Proc. Natl. Acad. Sci. U.S.A. 40, 26138-26148). SREBP-2 is produced by a different gene and contains a long activation domain resembling that of SREBP-1a. Recent evidence suggests that the main function of SREBP-2 is to regulate cholesterol synthesis whilst that of SREBP-1 is to regulate fatty acid synthesis (Pai et al., supra).
Inhibition of SREBP transcription factor function will lead to reduced cellular synthesis of free fatty acids and cholesterol, the clinical benefits of which are expected to include increased cellular insulin sensitivity and reduced coronary artery disease (CAD). Furthermore, SREBP-1 represents a cellular mechanism for increasing both fat cell size and number (Kim et al. (1998) J. Clin. Invest. 101, 1-9). Since most obesity generally involves an increase in both cell size and cell number, inhibition of SREBP-1 might be expected to have a positive effect on obesity. The hypolipidemic effects of dietary polyunsaturated fatty acids are believed to derive from a direct inhibitory effect on SREBP-1 expression (Xu et al. (1999) J. Biol. Chem. 274, 23577-23583).
There is data indicating independent regulation of SREBP-1 and SREBP-2 in hamster liver, suggesting the possibility for specific targeting of SREBP-1 or -2 (Sheng et al. (1995) Proc. Natl. Acad. Sci. U.S.A. 92, 935-938).
Transgenic mice over-expressing a dominant-positive form of SREBP-2 in the liver and adipose tissue showed greatly increased levels of mRNAs encoding multiple enzymes of cholesterol synthesis. Enzymes involved in fatty acid synthesis were also increased, however, to a lesser extent (Horton et al. (1998) J. Clin. Invest. 101, 2331-2339). Transgenic mice over-expressing a constitutively active SREBP-1a in the liver and adipose tissue showed greatly increased mRNA levels for enzymes involved in fatty acid and cholesterol (Shimano et al. (1996) J. Clin. Invest. 98, 1575-1584). Their livers were enlarged about 4-fold due to a massive accumulation of free fatty acids and cholesterol. Over-expression of a corresponding version of SREBP-1c in adipocytes of transgenic mice yielded insulin resistance and diabetes (Shimomura et al. (1999) Genes Dev. 12, 3182-3194). In cell culture such overexpression was previously shown to promote adipocyte differentiation. It has further been shown that overnutrition increases SREBP-1c expression in liver and islets of obese fa/fa Zucker diabetic fatty rats (Kakuma, T. et al. (2000) Proc. Natl. Acad. Sci. U.S.A. 97: 8536-8541).
S-1 Protease
As discussed above, SREBPs are activated by proteolysis, which releases the active transcription factor. The luminal subtilisin-like protease Site-1 Protease (S1P) is responsible for the first of the two proteolytic steps. Cleavage by S1P enables further cleavage by a Site-2 protease. S1P is the target for feedback inhibition by cholesterol.
S1P from hamster has been cloned (Sakai et al. (1998) Molecular Cell 2, 505-514). (GenBank accession no. AF078105; SEQ ID NOS: 5 and 6). The corresponding sequence of the (then unidentified) human gene was disclosed by Nagase et al. (1995) DNA Research 2, 37-43 (GenBank Accession no. D420453; SEQ ID NOS: 3 and 4)
SREBP and S1P are co-localized with a third protein: SREBP Cleavage-Activating Protein (SCAP), which is required for Site-1 cleavage in vivo. SCAP contains a site for sterol regulation, conserved in a small number of proteins, e.g. HMG-CoA reductase.
Only one S1P has been identified among the human expressed sequence tags (ESTs). Thus, S1P may be the only member of a subfamily among the subtilisin-like proteases.
Consequently, SREBPs are important regulators of fat and sugar metabolism in mammals and direct or indirect down-regulation of SREBPs may be of therapeutic value in type II diabetes; obesity, hypercholesterolemia, and other cardiovascular diseases or dyslipidemias.
Site-1 Protease represents a molecular target for therapeutic intervention which is expected to interfere with the SREBP pathway. Two principally distinct concepts for inhibition of the site-1-protease activity may be postulated; (i) by inactivation of the proteolytic activity (classical inhibitors) or (ii) by modulation of the site-1-protease gene expression level. In order to modulate the expression of the site-1-protease gene, there is a need for identification of regulatory regions responsible for the regulation of Site-1 protease promoter. Such regulatory regions in the promoter could be used for the identification of agents that inhibit expression of Site-1 protease, and thereby for the inhibition of the SREBP pathway.
The 5xe2x80x2-flanking region (promoter region) of the human Site-1 Protease (S1P) gene has been cloned and sequenced. This promoter region is useful in biological assays for the identification of compounds that inhibit the transcription of the Site-1 Protease. Inhibition of the SREBP pathway is expected to have therapeutic value in type II diabetes; obesity, hypercholesterolemia, and other cardiovascular diseases or dyslipidemias.
Consequently, in a first aspect this invention provides an isolated human site-1 protease promoter region comprising a sequence selected from:
(a) the nucleotide sequence set forth as SEQ ID) NO: 2, or a fragment thereof exhibiting site-1 protease promoter activity;
(b) the complementary strand of (a); and
(c) nucleotide sequences capable of hybridizing, under stringent hybridization conditions, to a nucleotide sequence as defined in (a) or (b).
The term xe2x80x9cpromoter regionxe2x80x9d refers to a region of DNA that functions to control the transcription of one or more genes, and is structurally identified by the presence of a binding site for DNA-dependent RNA polymerase and of other DNA sequences on the same molecule which interact to regulate promoter function.
The nucleic acid molecules according to the present invention includes cDNA, chemically synthesized DNA, DNA isolated by PCR, genomic DNA, and combinations thereof. Genomic DNA may be obtained by screening a genomic library with the cDNA described herein, using methods that are well known in the art.
In a preferred form of the invention, the said nucleic acid molecule has a nucleotide sequence identical with SEQ ID NO: 2 of the Sequence Listing. However, the nucleic acid molecule according to the invention is not to be limited strictly to the sequence shown as SEQ ID NO: 2. Rather the invention encompasses nucleic acid molecules carrying modifications like substitutions, small deletions, insertions or inversions, which nevertheless have S1P promoter activity. Included in the invention are consequently nucleic acid molecules, the nucleotide sequence of which is at least 90% homologous, preferably at least 95% homologous, with the nucleotide sequence shown as SEQ ID NO: 2 in the Sequence Listing.
The term xe2x80x9cstringent hybridization conditionsxe2x80x9d is known in the art from standard protocols (e.g. Ausubel et al., supra) and could be understood as e.g. hybridization to filter-bound DNA in 0.5 M NaHPO4, 7% sodium dodecyl sulfate (SDS), 1 mM EDTA at +65xc2x0 C., and washing in 0.1xc3x97SSC/0.1% SDS at +68xc2x0 C.
The said xe2x80x9cfragmentxe2x80x9d (partial sequence) exhibiting site-1 protease promoter activity can be identified by the skilled person by computer-assisted sequence analysis, e.g. prediction of transcription factor binding sites.
The invention further provides a recombinant construct comprising the human site-1 protease promoter region as defined above. Preferably, the said construct comprises the S1P promoter region operably linked to a gene encoding a detectable product, in particular the human site-1 protease gene (SEQ ID NO: 3).
The term xe2x80x9clinkedxe2x80x9d indicates that a nucleotide sequence encoding a gene product and an S1P promoter, or an active fragment thereof, are located within a continuous nucleic acid sequence. The term xe2x80x9coperably linkedxe2x80x9d means that a nucleotide sequence, which can encode a gene product, is linked to the S1P promoter such that the S1P promoter regulates expression of the gene product under appropriate conditions. Two nucleotide sequences that are operably linked contain elements essential for transcription, including, for example, a TATA box.
The recombinant construct according to the invention could further comprise a reporter gene. As used herein, the term xe2x80x9creporter genexe2x80x9d means a gene encoding a gene product that can be identified using simple, inexpensive methods or reagents and that can be operably linked to a S1P promoter or an active fragment thereof. Reporter genes such as, for example, a luciferase, xcex2-galactosidase, alkaline phosphatase, or green fluorescent protein reporter gene, can be used to determine transcriptional activity in screening assays according to the invention (see, for example, Goeddel (ed.), Methods Enzymol., Vol. 185, San Diego: Academic Press, Inc. (1990); see also Sambrook, supra).
In another aspect the invention provides a vector comprising the recombinant construct as defined above. The term xe2x80x9cvectorxe2x80x9d refers to any carrier of exogenous DNA that is useful for transferring the DNA to a host cell for replication and/or appropriate expression of the exogenous DNA by the host cell. A host cell stably transformed with the recombinant construct is an additional aspect of the invention. Such a host cell can be a prokaryotic cell, a unicellular eukaryotic cell, or a cell derived from a multicellular organism. The methods employed to effect introduction of the vector into the host cell are standard methods well known to a person familiar with recombinant DNA methods. The term xe2x80x9ctransformedxe2x80x9d or xe2x80x9ctransfectedxe2x80x9d refers to the process by which exogenous DNA is transferred into an appropriate host cell.
In a further important aspect, this invention is useful in screening for pharmacological agents that modulate S1P levels by affecting the transcription of the S1P gene. As used herein, the term xe2x80x9cagentxe2x80x9d means a biological or chemical compound such as a simple or complex organic molecule, a peptide, a protein or an oligonucleotide. Consequently, this invention includes a method for identifying an agent capable of modulating the S1P promoter, comprising providing a cell comprising the S1P promoter; contacting said cell with a candidate agent; and monitoring said cell for an effect that is not present in the absence of said candidate agent.
A preferred form of the invention include a method for identification of an agent capable of decreasing or inhibiting site-1 protease promoter activity, said method comprising the steps (i) contacting a candidate agent with the human site-1 protease promoter; and (ii) determining whether said candidate agent decreases expression of the site-1 protease gene, such decrease being indicative for an agent capable of decreasing or inhibiting site-1 protease promoter activity.
For screening purposes, appropriate host cells can be transformed with a vector having a reporter gene under the control of the human S1P promoter according to this invention. The expression of the reporter gene can be measured in the presence or absence of an agent with known activity (i.e. a standard agent) or putative activity (i.e. a xe2x80x9ctest agentxe2x80x9d or xe2x80x9ccandidate agentxe2x80x9d). A change in the level of expression of the reporter gene in the presence of the test agent is compared with that effected by the standard agent. In this way, active agents are identified and their relative potency in this assay determined.
It will be understood that agents acting on the human S1P promoter can be identified by, as an additional step, analyzing direct binding interactions between the candidate agent and the human S1P promoter. Interactions with large molecules may be studied using techniques such as gel shift analysis, footprinting or NMR (see Latchman, D. S. (Ed.) (1995) Methods for studying transcription factors. In: Eukaryotic transcription factors. Academic Press, London, pp. 17-44). Small molecule compounds which appear to bind reversibly to double stranded DNA without intercalation between DNA base pairs have been defined. Methods are described by which this non-intercalative binding can be characterized using ultraviolet spectrometry, fluorimetry with ethidium as a probe, viscometry and other hydrodynamic techniques, circular dichroism and nuclear magnetic resonance spectrometry (See Baguley, B. C. (1982) Nonintercalative DNA-binding antitumour compounds. Mol Cell Biochem 43: 167-181; Gmeiner, W. H. (1998) NMR spectroscopy as a tool to investigate the structural basis of anticancer drugs. Curr Med Chem 5(2):115-135; Wemmer, D. E. and Williams, P. G. (1994) Use of nuclear magnetic resonance in probing ligand-macromolecule interactions. Methods Enzymol. 239:739-767)
A potentially useful method for identification of agents acting on the human S1P promoter is described in Swedish patent application No. 0101218-6, filed on Apr. 5, 2001. Such a method comprises the steps
(a) predicting the structure of an RNA-fragment;
(b) choosing a suitable predicted RNA-fragment of step (a), which RNA-fragment comprises at least one individual stem;
(c) synthesizing the DNA-fragment corresponding to the RNA-fragment of step (b);
(d) inserting the DNA-fragment of step (c) in the upstream proximity of a reporter assay gene, which reporter assay gene produces a signal upon translation, thereby forming a reporter construct;
(e) performing a reporter gene assay, which assay monitors the interaction between a molecule to be tested for RNA-binding and the RNA-fragment of the reporter construct.
As mentioned above, it is expected that agents capable of decreasing or inhibiting site-1 protease promoter activity have potential therapeutic value in particular in obesity, and in type II diabetes; hypercholesterolemia, atherosclerosis and other cardiovascular diseases or dyslipidemias. Consequently, the invention comprises a method for the treatment of medical conditions related to obesity, comprising administering to a patient in need thereof a therapeutically effective amount of an agent identified by the method according to the invention.
The term xe2x80x9ctreatmentxe2x80x9d means any treatment of a diseases in a mammal, including: (i) preventing the disease, i.e. causing the clinical symptoms of the disease not to develop; (ii) inhibiting the disease, i.e. arresting the development of clinical symptoms; and/or (iii) relieving the disease, i.e. causing the regression of clinical symptoms. The term xe2x80x9ceffective amountxe2x80x9d means a dosage sufficient to provide treatment for the disease state being treated. This will vary depending on the patient, the disease and the treatment being effected.
Throughout this description the terms xe2x80x9cstandard protocolsxe2x80x9d and xe2x80x9cstandard proceduresxe2x80x9d, when used in the context of molecular biology techniques, are to be understood as protocols and procedures found in an ordinary laboratory manual such as: Current Protocols in Molecular Biology, editors F. Ausubel et al., John Wiley and Sons, Inc. 1994, or Sambrook, J., Fritsch, E. F. and Maniatis, T., Molecular Cloning: A laboratory manual, 2nd Ed., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. 1989.


Provided is a method for producing an oxide and/or hydroxide wherein the ratio of oxide and hydroxide has been controlled. The method produces an oxide, a hydroxide, or a mixture thereof, and obtains an oxide and/or a hydroxide wherein the ratio of oxide and hydroxide has been controlled by means of changing a specific condition relating to at least one fluid to be processed introduced between processing surfaces (1, 2) when causing the precipitation of the oxide, hydroxide, or mixture thereof by mixing an basic fluid containing at least one type of basic substance and a fluid containing at least one type of metal or metallic substance as the fluids to be processed between the processing surfaces (1, 2) that are provided facing each other, are able to approach to and separate from each other, and of which at least one rotates relative to the other. The specific condition is at least one condition selected from the group consisting of: the speed of introduction of at least one of the fluids to be processed; and the pH of at least one of the fluids to be processed.

In recent years, an oxide, a hydroxide, or a hydroxide as a precursor to an oxide have been wanted in a wide field such as a catalyst, a conductive material, a magnetic material, a secondary electron releasing material, a luminescent material, a heat absorber, an energy storage material, an electrode material, and a coloring material; and in accordance with its object and requirement, any one of an oxide and a hydroxide or both having a controlled ratio of the oxide to the hydroxide have been considered to be necessary. For example, zinc oxide has been widely used as a transparent electrode, a fluorescent material, a drug, and so forth because of its electrical, optical, and chemical characteristics. In considering its intended use and characteristics, zinc oxide is produced in a certain case by preparing zinc hydroxide or a mixture of zinc oxide and zinc hydroxide, which is followed by baking thereof; and in this case, any one of the oxide and the hydroxide or both having a controlled mixing ratio of the oxide to the hydroxide are considered to be necessary.
As to the method for producing an oxide or a hydroxide, methods shown in Patent Document 1 and Patent Document 2 have been known; but it has been difficult to selectively obtain the oxide and the hydroxide by these conventional methods, so that it has been even more difficult to produce the oxide and the hydroxide having a controlled ratio of the oxide to the hydroxide. In addition, in the case that microparticles of an oxide or a hydroxide are produced in a reaction vessel as disclosed in Patent Document 2, reaction conditions tend to be inhomogeneous due to concentration distribution and temperature distribution in the reaction vessel; and thus, not only to control a ratio of the oxide to the hydroxide but also to obtain uniform particle diameter has been difficult.
Meanwhile, a method for producing ceramic microparticles as shown in Patent Document 3 has been provided by the present applicant, but a method to control a ratio of an oxide to a hydroxide has not been described specifically; and thus, a method for producing any one of an oxide and a hydroxide or both having a controlled ratio of the oxide to the hydroxide has been eagerly wanted.


An assembly for the collection and channeling of water leaking beyond a stuffing box or other seal assembly which is normally provided to isolate a rotating propeller shaft in a marine craft from the water in which the craft rides. A receiving chamber is disposed at an inner most end of the sealing assembly or stuffing box in receiving relation to leaking water passing along the shaft wherein the receiving chamber communicates with a liquid exit or collection facility for the removal of the water from the shaft before the water can enter into the interior of the craft.

1. Field of the Invention
This invention relates to a splash guard or like device to prevent leakage into a boat of water passing beyond the sealing assembly or stuffing box normally disposed to restrict leakage along the propeller shaft during operation of the boat.
2. Description of the Prior Art
In propeller driven marine craft, an elongated propeller shaft is rotatably driven at relatively high speeds in order to adequately drive the propeller for the propulsion of the craft through water. When the marine craft is designed to be propelled by an inboard motor, the propeller shaft usually assumes a relatively extended longitudinal dimension and passes through the bottom of the boat generally in the stern area so that the propeller may be properly located rearwardly and somewhat beneath the boat. In each instance, regardless of the size of the craft, a well known problem exists with water leaking into the interior of the craft frequently to the area of the engine compartment or engine room in larger marine crafts even though such leakage is attempted to be restricted by prior art sealing assemblies or stuffing boxes. Typically, such stuffing boxes include packing or like sealing material engaging the outer surface of the shaft while it is rotating. The stuffing box or sealing assembly is designed to effectively restrict or minimize the inflow of leakage or water from the exterior of the craft into its interior during rotation of the shaft. While excess leakage can be controlled to the extent of replacing the packing material of the stuffing box and/or "tightening" certain adjustable mounting features associated with most prior art stuffing boxes, the problem of leakage still exists and presents a major problem.
Accordingly, there is a need for an assembly which would effectively eliminate such leakage while not requiring structural modification of the craft and allow utilization of conventional packing assemblies or stuffing boxes by being cooperatively structured to capture and/or divert any flow of water leaking beyond the stuffing box of the rotating shaft.
Such a preferred assembly should be reliable in terms of preventing the aforementioned leakage, easy and inexpensive to install by being structurally adaptive to the structure and location of the rotating propeller shaft.


An adapter is used to connect a conventional lamp shade finial to a pull chain for a fan or the like. The adapter has a length of bead chain, and a threaded member on one end of the chain. A larger bead prevents the threaded member from coming off the chain; and, the threaded member is sized to be received by the standard base for a lamp shade finial. A lip on the threaded member limits the insertion of the threaded member into the finial base. The other end of the length of bead chain has a connector to connect the adapter to the existing pull chain, and this may be a conventional bead chain connector.

1. Field of the Invention
This invention relates generally to decorative pulls, and is more particularly concerned with an adapter for attaching a decorative pull to a pull chain.
2. Discussion of the Prior Art
There have been many efforts to provide a decorative pull to a pull chain. Such a pull serves the practical purpose of weighting the end of the cord and providing a device that is easy to grasp, and serves the decorative purpose of matching the pull to the general decor in both style and colors. The most common pulls are attached by the manufacturer of the device having the pull cord, and of course such pulls are not easily replaceable. Replacement is usually by replacement of the pull cord, the replacement having a different decorative pull. While this changes the pull, one is limited to the range of pulls available.
An adapter has been marketed for allowing a lamp shade finial to be attached to a pull chain, and such an adapter opens a very wide range of designs and colors for decorative pulls. The disadvantage of the prior art adapter is that it is large, complex and relatively expensive. In some cases, the adapter is so large as to detract from the pull. The prior art device is assembled of several parts that must be glued together, so both parts and labor are more expensive.


A toothed belt having a body with a length, an inside surface, an outside surface, laterally spaced sides, and a plurality of teeth spaced in a lengthwise direction on the inside of the body. An elongate, load carrying cord extends lengthwise of the body and is embedded in the body. A cloth layer is provided on the inside surface of the body. The load carrying cord has a diameter that is greater than 1.1 mm and not greater than 1.5 mm and is prepared by a) bundling glass fiber filaments each having a diameter of from 5 to 10 .mu.m into strands, b) gathering and primary twisting a plurality of stands in one twist direction to form strings, and c) gathering and final twisting the strings in a direction oppositely to the one twist direction.

1. Field of the Invention
This invention relates to power transmission belts and, more particularly, to a belt which has drive/driven teeth along the length thereof.
2. Background Art
Unlike flat belts, V-belts, and the like, toothed belts are not prone to slipping and therefore are highly efficient in transmitting driving forces. Toothed power transmission belts have an advantage over gears, chains, and the like, because they generally do not generate the same level of noise in operation. Because of these advantages, toothed belts are becoming widely used. As one example, toothed belts are used for synchronous driving of overhead cam (OHC) shafts in automobiles. The field of use for these toothed belts continues to expand.
Toothed belts for driving OHC shafts may be operated in automobile engine compartments at high temperatures, at high speeds, and under heavy loads. Automobiles are being redesigned with higher performance internal combustion engines which are operated in even smaller engine compartments. As a result, toothed belts are required to operate in environments at even higher temperatures and still further to wrap around pulleys with relatively small diameters, which often requires the belts to bend at severe angles.
In known toothed belts, load carrying cords are embedded in a back layer at predetermined intervals along the belt width. When such belts are operated around small diameter pulleys, the load carrying cords must bend sharply and are thus required to be highly flexible. In the absence of the necessary flexibility and resiliency, the load carrying cords may break after a relatively short running period.
In one conventional construction, load carrying cords for toothed belts are prepared by bundling and twisting E-glass/ordinary non-alkali glass fiber filaments. One such load carrying cord construction is shown in JP-A 62-159827.
In one known construction, load carrying cords are prepared by dipping E-glass fiber filaments with a diameter of 9 .mu.m in a resorcinol-formalin resin latex mixture (hereinafter RFL). The filaments are bundled into strands which are twisted in a 3/13 process. That is, 3 strands of RFL-processed glass fiber filaments are primary twisted into a string, followed by final twisting of 13 of the strings into a load carrying cord.
This latter type of belt may have a shortened life in certain high performance internal combustion engines. The life of these high performance internal combustion engines is being increased while the life of the toothed belts used in those engines may not be proportionately lengthened. As a result, the toothed belts used for OHC shaft driving may have to be changed relatively frequently during the life of an automobile.
Another problem with toothed belts in this environment, i.e. at high speeds around small diameter pulleys, is that the fibers making up the load carrying cords may generate a significant amount of frictional heat in the belts. This may degrade the adhesion between a canvas covering cloth and the rubber. This heat may also affect the adhesion between the load carrying cords and the rubber. Further, the heat may have a negative influence on both the canvas covering cloth and the rubber making up the belt body. All of these problems contribute to a potentially shortened life for a toothed belt in this environment.
In JP-B 5-44607U, a toothed belt is described with load carrying cords prepared by processing high-strength E-glass fiber filaments, having a diameter from 6 to 8 .mu.m, with RFL. A predetermined number of the processed filaments are bundled into strands and twisted with a primary twist count of from 7.2 to 8.8 twists/10 cm to produce strings of from 500 to 800 filaments per string. The strings are in turn final twisted at a count of from 7.2 to 8.8 twists/10 cm in a direction opposite to the primary twist direction to produce load carrying cords with 9-12 strings per cord.
Even with this type of load carrying cord, in the environment of the modern internal-combustion engines, the load carrying cords may elongate with the belt run under a heavy load. As a result, the belt itself may be elongated. If this occurs, the belt teeth may not properly engage with cooperating pulleys, eventually potentially leading to abrasion, cracking and potential breakage in a relatively early stage of the anticipated belt life.
Further, if the width of the belt is reduced to minimize the overall size of the belt and associated components, even under an ordinary load, the load per unit width of the belt may be relatively large. The teeth in this situation are likewise prone to cracking and breaking prematurely.
It is known to cover the teeth with a nylon cloth. However, since the initial tension of the belt under heavy load may be high, the abrasion resistance of the nylon cloth may not be satisfactory. The land region between adjacent teeth may become abraded at an early stage in the belt life. The teeth may crack or break to prematurely end the belt life.


A piston for an air pump has a connecting rod and a sealing valve. The connecting rod has a seat. The seat has a groove and a retaining surface. The groove is defined in an outer surface of the seat. The retaining surface is adjacent to the groove. The sealing valve movably engages the seat of the connecting rod and has an engaging ring and a sealing part. The engaging ring has an inwall which extends into the groove and has an engaging surface facing the retaining surface. The sealing part is connected with the inwall of the engaging ring and sealingly covers the through hole. The sealing valve is not prone to deformation and warpage during the operation of the piston to prevent any operating noise problem.

1. Field of the Invention
The invention relates to a piston for an air pump, and more particularly to a piston for an air pump to enhance the sealing effect, to prevent deformation of a valve and to reduce operating noise.
2. Description of Related Art
An air pump for inflating tires or airbeds generally comprises a motor, a piston cylinder and a piston. The piston reciprocates in the piston cylinder by operation of the motor, and the piston can compress the air in the piston cylinder to high pressure gas for inflation.
The piston has a piston seat and an elastic flap. The piston seat is mounted at a top end of the piston and has a through hole. The elastic flap is mounted on a top end of the piston seat and covers the through hole. When the piston is driven by the motor, the airflow impacts the elastic flap to lift the elastic flap from the through hole, and then the airflow flows through the through hole into the piston cylinder. When the piston is driven by the motor at the next time, and the airflow will be pushed to flow out the piston cylinder.
The conventional piston has the following disadvantages:
1. The elastic flap is mounted on the piston seat by a rivet, so the combination between the elastic flap and the piston seat is complex. Moreover, the elastic flap becomes warped and deformed when the air pump has been used for a period. Then, a gap is formed between the elastic flap and the piston seat or the elastic flap does not hermetically cover the through hole of the piston seat. Thus, the working efficiency of the piston is poor.
2. The elastic flap is metal and causes a noise when the elastic flap returns to cover the through hole of the piston seat.
3. The material cost of the elastic flap is high.
To overcome the shortcomings, the present invention provides a piston for an air pump to obviate the aforementioned problems.


This invention relates to a line guiding assembly comprising a line guiding trough and a line assembly guided therein which includes a plurality of ribbon cables held within an encapsulant and reinforcement channels. The line assembly forms a loop with a lower length and an upper length. A ribbon material either in a drum or coil is provided that fits inside the loop wherein the coil of ribbon material is between the upper and lower lengths of the line reinforced assembly and extends and retracts in the same direction as the movement of the loop and lengths of the assembly. The ribbon material is different from the material of the line assembly and is preferably stainless steel. A double ended system with two line assemblies operating in a single trough is also provided.

It is often required to provide a connection between a piece of equipment which is in linear motion, such as a robot and a stationary piece of equipment, such as a control panel wherein the connection does not hinder the motion of the moving piece of equipment and wherein the reliability of the connection is adequate and sufficiently durable to sustain the system through a large number of motions.
A line guiding assembly which accomplishes these objectives includes U.S. Ser. No. 07/807,018. Although the connection of this line guiding assembly is sufficiently durable, when this assembly is used for long intervals, debris is generated by the abrasion at the surfaces of the upper and lower lengths as they travel against each other. This debris may collect in the area surrounding the line guiding assembly and may be cosmetically undesirable and/or the debris may serve as an airborne carrier of static charge which may be unacceptable in certain applications.
The line guiding assembly of U.S. Ser. No. 07/807,018 also requires a large driving force to overcome the static friction that exists between the upper and lower lengths and put the mobile piece of equipment into motion.
There is a need to improve the line guiding assembly to eliminate the creation of debris and provide a system where a lesser driving force to move the mobile piece of equipment is provided.


A method and circuitry for generating a trigger signal based on an oscillation signal and associated non-transitory computer program product are provided. The method includes following steps. Firstly, a calibration value is obtained according to a reference frequency and a frequency of the oscillation signal, and a counting value is gradually altered from a first initial value to a breakpoint value. Secondly, the counting value is updated to a second initial value when the counting value is equal to the breakpoint value. Then, the counting value is gradually altered from the second initial value to a final value, and the trigger signal is generated when the counting value is equal to the final value.

Technical Field
The disclosure relates in general to an oscillator, and more particularly to a method and a circuitry for generating a trigger signal based on an oscillation signal and associated non-transitory computer program product.
Description of the Related Art
In electronics and especially synchronous digital circuits, a clock signal oscillating between a high level state and a low level state is essential. FIG. 1 is a schematic diagram illustrating a crystal oscillator used in a digital circuit. Crystal oscillators 11 are widely used for generating clock signals (CLK). A chip 10 of the digital circuit 1 is synchronized by the clock signal (CLK).
The requirement for low power (hereinafter, LP) consumption has been growing at an exponential rate, and many electronic devices provide a power saving mode (for example, standby mode, sleep mode etc.). In order to ensure the electronic product can swiftly change from the power saving mode to a normal mode, the crystal oscillator 11 continues to operate even if the chip 10 is disabled in the power saving mode. However, power assumption of the crystal oscillator 11 is relatively high and should not be neglected.
Since the crystal oscillators consume significant power, on-chip oscillators (for example, LP oscillator) are designed to replace the crystal oscillators in the power saving mode. Although the on-chip oscillators consume less power than the crystal oscillator, frequency of the LP oscillator is not as accurate as frequency of the crystal oscillator. That is to say, the LP oscillator is not suitable for application having tighter frequency tolerances. Consequentially, selecting an oscillator to meet both the requirement of accuracy and low power consumption becomes a dilemma.

Method and circuitry for generating trigger signal and associated non-transitory computer program product


A logarithmic power detector includes a power distributor, a first detection circuit, a second detection circuit and an output circuit. The power distributor is used to generate a first power signal and a second power signal according to an input signal. The first detection circuit is used to attenuate the first power signal to generate a first rectified signal, filter the first rectified signal to generate a first low-pass signal, and amplify the first low-pass signal to generate a first amplification current. The second detection circuit is used to attenuate the second power signal to generate a second rectified signal, filter the second rectified signal to generate a second low-pass signal, and amplify the second low-pass signal to generate a second amplification current. The output circuit is used to receive the first amplification current and the second amplification current to generate a converted voltage related to the input signal.

In radio frequency (RF) communication, the power amplifier generates RF signals for transmission via an antenna. The power of the RF signal needs to be controlled within a specific power range to enable transmission within the predetermined coverage while reducing signal interference. The logarithmic power detector detects the power of the RF signal and controls the power amplifier to adjust the power of the RF signal. However, the conventional logarithmic power detector cannot accurately measure the power of the RF signal, and its operation bandwidth is limited.
Therefore, a logarithmic power detector is needed to accurately detect the power of the input signal and increase the linearity and operational bandwidth of the output signal.


Upon starting instruction of a compressor before the compressor is started, a pressurized water jet line 20 is opened and pressurized water is jetted to the inside of the compressor. By this manner, a dry operation with rotors and a mechanical seal kept in a dry state is definitely prevented and the compressor can be started even after it is stopped for a long hour. Further, the compressed air is supplied to the inside of the water tank, and the water from the water tank is jetted to the inside of the compressor by its pressure. The compressed air ejected from the water tank is cooled below a saturation temperature of water content and the water content thereof is condensed and separated. The separated water content is supplied to the inside of the compressor, and an excess circulating water is discharged from the water tank. Thus, a long hour continuous operation can be performed without replenishing water.

(1) FIELD OF THE INVENTION
The present invention relates to a water jet type air compressor system into which water is jetted in order to perform lubrication or the like, a starting method for the system, and a water quality control method for the system.
(2) DESCRIPTION OF THE RELATED ART
FIG. 1 is a schematic view of a screw compressor. In this drawing, a screw compressor 10 is a biaxial screw compressor, which is constituted of two screw rotors 1, bearings 2a, 2b, a high pressure seal (e.g., a mechanical seal 3), a low pressure seal (e.g., a lip seal 4), a compressor main body 5 and the like. This screw compressor 10 rotatively drives two screw rotors 1 engaged with each other, compresses the air introduced from an air intake 5a between the two rotors, and discharges the compressed air from a discharge opening 5b. Incidentally, the mechanical seal can also be used as the low pressure seal, and in this case, water is supplied to both mechanical seals.
FIG. 2 is an external view of the screw compressor of FIG. 1. In this drawing, 6a is a pulley for driving the rotors and 5c is a water supply port to the mechanical seal. In the compressor of such screw compressor, since seal faces or frictional faces (the material of which is carbon or ceramics) of the rotors 1 and the mechanical seal 3 have a structure of directly sliding, water is jetted and supplied from the air intake and the water supply port 5c so as to lubricate the sliding faces. Incidentally, this water serves not only to lubricate and cool the sliding faces, but also to improve compression efficiency by cooling the compressed air.
FIG. 3 is a block diagram of the air compressor equipment using such a water jet type compressor. In this drawing, 7 is a fan motor (a motor with fan), 8 is a water tank, and 9 is a water cooler. The fan motor 7 drives the pulley 6b with a fan 7a for blowing the air to the water cooler 9, and rotatively drives the pulley 6a for driving the rotors by a belt. By the rotative driving of the pulley 6a, the inner rotors rotate, and the air is introduced from an air introducing line 12a through the air intake 5a. A compressed air compressed between the rotors is supplied to the water tank 8 from the discharge opening 5b through a compressed air line 12b.
In the water tank, water is supplied up to an intermediate position, and the inner water is forcibly fed to the water cooler 9 through a water line 13a by pressure (about 0.7 Mpa: about 7 Kg/cm.sup.2 g) of pressurized air supplied to the upper part, and here it is cooled and, further, it is supplied to the air intake and the water supply port 5c of the compressor 10 through a water line 13b and jetted inside thereof. The water which has lubricated and cooled the inside of the compressor 10 is circulated in the water tank 8 with the pressurized air, separated by a mist separator 8a, and mixed with the inner water inside the water tank 8. On the other hand, the pressurized air from which water content is eliminated is ejected from a check valve 8b.
As described above, in the conventional water jet type air compressor system, water is supplied to the rotors or the mechanical seal of the water jet type compressor 10 during operation, thereby providing for lubrication and cooling. However, when the compressor stops and pressure inside the water tank 8 continues to be in a normal pressure state for a long time, since the compressor is usually located at a high position, the water level goes down and the water line 13a and the inside(the rotors and the mechanical seal) of the compressor 10 are kept in a dry state.
For this reason, when the compressor was started in this dry state (hereinafter referred to as a dry operation), there was a problem in that the compressor was operated in a dry state during the time till a circulating water arrived at the rotors and the mechanical seal. This dry operation time is the time until pressure inside the water tank is increased by driving the compressor and the circulating water arrives at the rotors or the mechanical seal by pressure of the compressed air. This dry operation time is, for example, about 5 to 10 seconds. During this dry operation, there has been a problem in that lubricating and cooling effect are not available owing to the dry state, and compared to a state wherein water is supplied, wear and temperature rise of the rotors or the mechanical seal become severe, thereby causing inconveniences such as damages or lowering of the performance and shortening of the exchange cycle.
On the other hand, as described above, in the conventional water jet type air compressor system, water is supplied to the rotors or the mechanical seal of the water jet type compressor 10 during operation, thereby providing for lubrication and cooling. This water is circulated between the water tank and the compressor, and a part of the water mist contained in the compressed air and an evaporated water content (a vapor) are not separated by the mist separator 8a but supplied to a supply destination from an air outlet. Hence, there has been a problem in that the circulating water was gradually reduced, thereby requiring a periodic replenishment of the water.
Further, since no impurity is contained in the vapor lost by evaporation, when ordinary service water containing a hard component is used as starting water, there has been a problem in that impurities in the circulating water condensed and scale trouble occurred. For this reason, a demineralizer or a water quality purifying device becomes indispensable, which makes the system complex and expensive. Further, the cyclic exchange of ion exchange resin or filters becomes indispensable for the demineralizer or the water quality purifying device, thereby incurring a maintenance cost.
Further, there is a problem in that impurities in the circulating water, particularly solid material have a bad effect on frictional faces of the mechanical seal or the rotors and increases wear thereof. In order to eliminate such solid material, a filter is disposed in the circulating water path. However, if filtering accuracy is enhanced, not only is the exchange cycle of the filter shortened, but also elimination of microscopic particles by the filter as such is difficult.
Further, when the circulating water is continuously used for a long time, bacteria is bred in the circulating water, and this bacteria, accompanied by the compressed air with water mist, becomes a source of asthma and allergies. Hence, in the conventional water jet type air compressor system, there has been a problem in that the inner circulating water was required to be exchanged by periodically stopping the system with a result that a working rate of the system was reduced.
To solve these problems, for example, Japanese Patent Application Laid-open No. 1448387/1983 discloses an "Adjustment method of the water for compressor". However, this method simply and automatically supplies the water by disposing a sensor, and does not basically solve the problems as described above.

Water jet type air compressor system, its starting method, and water quality control method thereof

Ishikawajima-Harima Heavy Industries Co., Ltd.


The present invention relates to a porous film including polyethylene and pore-forming particles, wherein the porous film has a structure including lamella and fibril, and the average size of pores located inside the porous film is larger than the average size of pores located on the surface of the porous film; a separator including the same; and an electrochemical cell.

A separator for an electrochemical cell is a porous film as an interlayer separating positive and negative electrodes in the cell and thus maintaining ion conductivity and charging and discharging the cell.
This porous film is manufactured in a method of a dry process and a wet process. The wet process is a method of mixing a polymer material with a plasticizer, extruding the mixture into a sheet, and removing the plasticizer from the sheet to form a pore. In the wet process, since a pore size is determined by a type of a plasticizer and compatibility of the polymer material with a plasticizer, sizes of the pores may be uniform but it is difficult to apply the same process to materials other than polyethylene, and there are problems that a solvent for extracting the plasticizer is harmful to human body and the environment, and drawbacks that processability and economy are not good.
The dry process is a method of forming a precursor film through extrusion, adjusting alignment of lamellas through a heat-treatment and the like to, and then, drawing the precursor film to form a pore. The dry process disclosed in Korean Patent Laid-Open Publication No. 2008-0085922 uses no extraction solvent unlike the wet process and thus is environmentally-friendly and competitive in terms of price but has a problem of having a low drawing rate and deteriorating tensile strength in a horizontal direction, since a pore is formed between crystalline materials and non-crystalline materials by drawing a single material.
In the dry process, a pore size is determined by an intensity difference between the crystalline materials and non-crystalline materials, so the pore size tends to be determined by types of materials. Generally, a porous film produced by a dry process using polyethylene has an excessively large pore size and thus may not be used as a separator. Therefore, a polypropylene porous film having a small pore size is used alone, or a polyethylene porous film is combined with a polypropylene porous film to provide a separator having a shutdown function. However, the polypropylene porous film has poor producibility and workability as compared with polyethylene porous film, and there are limits for a use of an organic solvent in preparation of a coated separator in order to improve heat resistance, and there are drawbacks that a separator function such as a shutdown function may not be available.

Porous film, separator comprising same, and electrochemical cell


System and method for generating video frames. The system includes a frame generator which generates one or more intermediate frames based upon one base frames. Each of the base frames are comprised of a plurality of macroblocks. Furthermore, one or more of the macroblocks have a motion vector. The macroblocks are comprised of a plurality of pixels. In the frame generation process, the frame generator performs a number of steps such as: (i) determines whether frame generation is appropriate, (ii) examines the first and second base frames to check for the presence of textual characters, (iii) selects a frame generation method based upon information in the first and second frames, (iv) filters the generated frames. In one embodiment, the system includes a server computer having an encoder, a client computer having a decoder, and a network connecting the server computer to the client computer. In this embodiment, the frame generator resides and executes within the client computer and receives the base frames from the decoder.

1. Field of the Invention
The invention pertains to the field of video transmissions. More particularly, the invention pertains to a system and a method for generating video frames.
2. Description of the Related Art
Virtually all applications of video and visual communication deal with large quantities of video data. To create a video presentation, a rendering computer displays a plurality of digital images (xe2x80x9cframesxe2x80x9d) in succession, thereby simulating movement.
Currently, certain technical problems exist relating to transmitting and rendering a video presentation across low bandwidth computer networks. FIG. 1 illustrates a conventional streaming video system 100. In the video system 100, a media server 102 is connected via a network 104 to a rendering computer 106. The media server 102 typically includes one or more video presentations 110 for transmission to the rendering computer 106.
One problem that is encountered in current streaming systems is that the transmission bandwidth between the media server 102 and the rendering computer 106 is not sufficient to support a real-time seamless presentation, such as is provided by a standard television set. To overcome this problem and allow the user to receive the presentation in real-time, the video presentation is often spatially and temporally compressed. Further, to reduce the amount of data that is transmitted, the media server 102 skips selected frames of the presentation, or, alternatively, the video presentation can be developed having only a few frames per second. The resulting presentations, however, are jittery and strobe-like and are simply not as smooth as a presentation that has a higher frame rate.
To increase the rate at which the frames are displayed to a user, a frame generator 112 may be used to provide intermediate frames between two selected reference frames of the video presentation 110. Typically, frame generators fall within one of two categories: linear motion interpolation systems and motion compensated frame interpolation systems. Linear motion interpolation systems superimpose two reference frames of the video presentation 110 to create one or more intermediate frames. Motion compensated frame interpolation systems use motion vectors for frame interpolation.
FIG. 2 illustrates the data format of a frame 200 according to one motion compensated frame interpolation system. The frame 200 of FIG. 2 is divided into nine horizontal groups of blocks (GOB). Each GOB includes eleven macroblocks. Each macroblock has four luminance blocks of 8 pixels by 8 lines followed by two downsampled chrominance blocks (Cb and Cr).
In motion compensated interpolation systems, selected macroblocks are assigned a motion vector based upon a reference frame. FIG. 3 illustrates an exemplary reference frame 300. Usually, the reference frame is the last frame that was transmitted to the rendering computer 106. Each motion vector points to an equivalently sized region in the reference frame that is a good match for the macroblock that is to be transmitted. If a good representation cannot be found, the block is independently coded.
By sending motion vectors that point to regions in the reference frame already transmitted to the rendering computer 106, the media server 102 can transmit a representation of a frame using less data than if the pixel information for each pixel in each block is transmitted.
Although current frame generators increase the frame rate, they are simplistic in design. These systems do not account for certain idiosyncrasies within selected streaming presentations. For example, current frame generators that use motion compensated frame interpolation do not account for video presentations that have textual characters. Often a video image is overlaid with video text to convey additional information to the viewer. If motion compensated frame interpolation generates an intermediate frame having textual characters, the generated frame may inappropriately move the text to a new position, thereby creating some floating text that was not intended by the creator of the video presentation.
Another problem associated with existing frame generators is that they unintelligently perform frame generation regardless of whether such interpolation results in a better quality video presentation. Although frame interpolation does increase the number of frames presented to the viewer, such frame generation can produce strange results under certain circumstances. Some encoders, for example, choose a motion vector for a selected block based only upon the fact that the motion vector references a block that is a good match for the selected block even though there is no actual motion from one corresponding frame to the other. Thus, since all of the vectors do not represent motion, frame generation in these instances should not always be employed.
Additionally, current frame generators do not perform any type of post filtering to the generated frames. As can be readily appreciated, since motion compensated interpolation systems build an intermediate frame using blocks of pixels, i.e., macroblocks, the pixels at the border of each block may not be a close match to the pixels in the neighboring block. Accordingly, the borders of each of the blocks may be readily visible to a viewer of the media presentation.
There is a need for a frame generator that behaves intelligently about the frame generation process. If frame generation would produce anomalous results, frame generation should not be performed. A frame generator should also determine whether the reference frames include textual characters and account for them in the frame generation process. A frame generator should also filter interpolation artifacts from the intermediate frame.
The frame generator of the present invention has several features, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this invention as expressed by the claims which follow, its more prominent features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled xe2x80x9cDetailed Description of the Inventionxe2x80x9d one will understand how the features of this invention provide advantages over other frame generators.
One embodiment of the invention includes a method of generating video frames, the method comprising receiving first frame data in a memory in the computer system, the first frame data representing a first video frame, the first frame data comprising a plurality of elements, each element corresponding to a group of pixels, receiving second frame data in the memory in the computer system, the second frame data representing a second video frame, the second frame data comprising a plurality of elements, each element corresponding to a group of pixels, determining which elements of the first and the second frames define, at least in part, video text, and generating at least one intermediate frame using the elements of the first frame and/or the second frame.
Another embodiment of the invention includes a system for generating video frames, the system comprising means for receiving a first frame in a memory in the computer system, the first frame representative of a digital image at a first time, the first frame comprising elements corresponding to pixel groups, means for receiving a second frame in the memory in the computer system, the second frame representative of the digital image at a second time, the second frame comprising elements corresponding to pixel groups, means for determining which elements of the first and the second frames define, at least in part, video text, means for generating at least one intermediate frame using the elements of the first frame and/or the second frame, wherein the intermediate frame represents at least one element at a position intermediate to respective positions whereat the at least one element is represented by the first frame and the second frame, and maintaining in the intermediate frame the spatial positioning of the determined textual elements of the first and/or second frames.
Yet another embodiment of the invention includes a method of generating frames having video text, the method comprising receiving a first frame having textual characters, determining whether the first frame includes textual characters, and generating a second frame, the second frame maintaining the positioning of the textual characters in the second frame with respect to the first frame.
Yet another embodiment of the invention includes a program storage device storing instructions which, when executed, perform the steps comprising receiving a first frame in a memory in the computer system, the first frame representative of a digital image at a first time, the first frame comprising elements corresponding to pixel groups, receiving a second frame in the memory in the computer system, the second frame representative of the digital image at a second time, the second frame comprising elements corresponding to pixel groups, determining which elements of the first and the second frame define, at least in part, video text, generating at least one intermediate frame using the elements of the first frame and/or the second frame, the intermediate frame representing at least one element at a position intermediate to respective positions whereat the at least one element is represented by the first frame and the second frame, and maintaining in the intermediate frame the spatial positioning of the elements determined to define video text elements.
Yet another embodiment of the invention includes a method of generating intermediate digital frames, the method comprising the steps of receiving a first frame having a plurality of macroblocks in a memory in the computer system, the first frame representative of an image at a first instance in time, the plurality of macroblocks each having four quadrants, each of the four quadrants, having a plurality of rows and columns of pixels, each of the pixels having an associated intensity value, receiving a second frame having a plurality of macroblocks in the memory in the computer system, the second frame representative of the image at a second instance in time, the plurality of macroblocks each having four quadrants, each of the four quadrants having a plurality of rows and columns of pixels, each of the pixels having an associated intensity value, and determining which macroblock quadrants of the first and the second frame define, at least in part, video text, the determining step comprising identifying a number edges that are within each of the macroblock quadrants, and determining whether the number of edges exceeds a threshold, generating at least one intermediate frame using the macroblock quadrants of the first frame and/or the second video frame, wherein the intermediate frame is representative an intermediate position of one or more selected macroblock quandrants in the first frame and/or the second frame, and maintaining in the at least one intermediate frame the spatial positioning of the macroblock quadrants determined to define video text.
Yet another embodiment of the invention includes a system for generating video frames, the system comprising: a frame analysis module for receiving frames, the frame analysis module detecting the presence of video text within the frames, and a frame synthesis module for generating frames between two received frames, the generated frames including the video text in the same spatial position as in either or both of the received frames.

System and method for generating video frames and detecting text


In general, the present disclosure is directed to a time of flight (ToF) sensor arrangement that may be utilized by a robot (e.g., a robot vacuum) to identify and detect objects in a surrounding environment for mapping and localization purposes. In an embodiment, a robot is disclosed that includes a plurality of ToF sensors disposed about a housing of the robot. Two or more ToF sensors may be angled/aligned to establish overlapping field of views to form redundant detection regions around the robot. Objects that appear therein may then be detected by the robot and utilized to positively identify, e.g., with a high degree of confidence, the presence of the object. The identified objects may then be utilized as data points by the robot to build/update a map. The identified objects may also be utilized during pose routines that allow the robot to orient itself within the map.

Some navigation approaches for robotic devices includes utilizing imaging systems to identify objects in an environment for mapping and localization purposes. Such systems may include one or more image sensors to perform object detection, wall tracking, and so on. For example, such systems may include multiple image sensors that each have a different field of view.
One such navigation and localization approach includes utilizing a simultaneous localization and mapping (SLAM) algorithm with image sensor data as an input. Often, multiple image sensors get utilized to ensure that front, back, and side views get captured for purposes of ensuring that environmental features/obstructions are factored into navigation decisions. Multiple image sensors can be particularly important when a robotic device can move in potentially any direction based on rotation about a center axis of the same. This ensures that the robotic device collects a sufficient amount of environmental data from each field of view to prevent collisions, falling down stairs, and so on. However, image sensors increase both cost and complexity in manufacturing robotic devices, as well as necessitate having sufficient hardware/software resources to capture and process multiple simultaneous image data streams.

Time of flight sensor arrangement for robot navigation and methods of localization using same


A semiconductor component includes a semiconductor body having a surface and a cutout in the semiconductor body. The cutout extends from the surface of the semiconductor body into the semiconductor body in a direction perpendicular to the surface. The cutout has a base and at least one sidewall. The component further includes a layer on the surface of the semiconductor body and in the cutout. The layer forms a well above the cutout. The well has a well base, a well edge and at least one well sidewall. The at least one well sidewall forms an angle α in the range of 20° to 80° with respect to the surface of the semiconductor body. The layer has at least one edge which, proceeding from the well edge, extends in the direction of the surface of the semiconductor body.

The semiconductor industry has always strived to achieve smaller feature sizes. For this purpose, it is necessary to reduce the size of the structure elements required. In this case, however, the tolerance limits must not be disregarded. Self-aligned production methods are increasingly being used for this purpose, and make it possible to meet the requirements for smaller structures while at the same time fulfilling tolerance ranges to be complied with.
Examples from power semiconductor technology for self-aligned structure elements are known from DE 102004057237 A1, which describes contact holes for channel/source regions in the case of gate trench transistors. The contact holes are produced in mesa regions between two trenches with a defined, small distance from the trenches. This can be done here either with the aid of so-called "spacers" or by means of an oxide layer—produced by thermal oxidation—as a mask for the contact hole etching. However, the tolerances are relatively large in the case of "spacers" and, in the case of the oxide masks, particularly in the case of gate trench transistors, the gate trench has to be produced with a greater depth in order to be able to carry out the thermal oxidation.

Method for producing a structure element and semiconductor component comprising a structure element


A cutting machine for cutting material from a crack that is present in a paved surface. The cutting machine has a circular cutting blade. The cutting blade has an axis of rotation and a mid-axis that is perpendicular to the axis of rotation. A wheeled platform is provided having wheels that are configured and oriented to cause the wheeled platform to turn about a predetermined point when the wheeled platform turns. A mounting arbor is supported under the wheeled platform. The mounting arbor retains the circular cutting blade in a position where its mid-axis generally aligns with the predetermined point around which the wheeled platform turns. The mid-axis of the cutting blade therefore remains in a fixed position when the wheeled platform is turned in a new direction. This allows the cutting blade to remain within the paved surface.

1. Field of the Invention
In general, the present invention relates to portable cutting machines that are used to cut grooves in paved surfaces. More particularly, the present invention relates to cutting machines that are used to cut away loose material from in and around cracks that may be present in the paved surface.
2. Prior Art Description
Many surfaces, such as streets, parking lots, driveways and the like are paved either in asphalt or concrete. Over time, cracks have a tendency to develop in the pavement material. As cracks develop, water is able to seep deeper and deeper into the pavement material. As the water, repeatedly freezes and thaws, the water expands the crack. This increases the size of the cracks, thereby letting even more water and dirt into the cracks. Once dirt is present in a crack, seeds can take root in the cracks. The roots of growing plants further increase the size and number of cracks, thereby letting more and more water, dirt and seeds into the pavement. Eventually, the prevalence and severity of the cracks become so pronounced that the integrity of the paved surface is compromised. Once so damaged, the paved surface cannot be economically repaired. The paved surface must, therefore, be either replaced or buried under a new paved surface.
In order to prevent a paved surface from becoming damaged, maintenance must be periodically performed on the paved surface. One of the most common and useful maintenance procedures is crack repair. During crack repair, the cracks in a paved surface are sealed. In this manner, water, dirt and seeds are prevented from entering the crack and degrading the paved surface. Small cracks can be sealed simply by covering the crack with tar or liquefied asphalt. However, larger cracks are often filled with dirt, leaves, gravel and other debris. These larger cracks must be cleaned of this debris before they can be properly sealed.
Each contractor has a preferred method of cleaning out large cracks in paved surfaces. For instance, some contractors rely upon manual labor and have men armed with pneumatic chisels manually clean large cracks. This technique produces good results, but is very time consuming and labor intensive. In attempts to make crack cleaning more efficient, motorized saws are sometimes employed. In the prior art, there are many portable motorized saws that are used to cut groves into a paved surface or asphalt or concrete. These saws typically have a round rotating blade that can be lowered into the paved surface as the saw is moved along the paved surface. Such motorized saws are designed to cut straight lines in pavement and are usually used to make stress relief joints and other long, straight cuts.
When such a motorized saw is used to clean a pavement crack, many problems occur. One big problem is that cracks rarely run straight. A saw must therefore constantly be turned in direction as it follows a crack. With many prior art saws, the saw blade must be lifted out of the pavement, the saw turned to a new direction, and the saw blade replunged into the pavement each time the motorized saw changes direction. If the saw is turned with the blade in the pavement, the saw blade can bind and/or break.
Another problem associated with pavement cracks is that pavement cracks vary in width and depth from point to point along the length of the crack. If a prior art motorized saw is used, the saw blade must be constantly adjusted in cut depth to avoid excessive wear. Furthermore, a blade thicker than the widest part of the crack must be used to ensure the blade fully cleans the crack. This causes the blade to cut far more material than is required in most parts of the crack. This results in excessive wear to the blade and greatly decreases the life of the blade.
A need therefore exists for a pavement cutting machine that is specifically designed to follow and clean pavement cracks, wherein the cutting machine avoids the disadvantages of prior art cutting machines that have been previously mentioned.

Apparatus for cleaning cracks in a paved surface in preparation of surface repair