A TFT device, a method of manufacturing the same, a TFT substrate and a display device, making it possible to decrease the photolithography steps, to improve the productivity and to decrease the cost of production. There are formed on the same substrate a first n-ch TFT having an LDD region which is entirely covered with a gate electrode, a second n-ch TFT having an LDD region partially covered with a gate electrode, and a p-ch TFT. Here, electrically conducting thin films and a gate electrode are formed on the electrically conducting thin film and on the insulating film, phosphorus ions are implanted into source/drain regions of the n-ch TFTs using the electrically conducting thin films and gate electrode as masks, and a gate electrode is formed by etching the electrically conducting thin film by using the electrically conducting thin film as a mask.

1. Field of the Invention
The present invention relates to a thin-film transistor device, a method of manufacturing the same, a thin-film transistor substrate provided therewith and a display device. More particularly, the invention relates to a thin-film transistor device having two kinds of polycrystalline silicon thin-film transistors of different types of electric conduction on the same substrate, a method of manufacturing the same, a thin-film transistor substrate provided therewith and a display device.
2. Description of the Related Art
Owing to its light weight, small thickness and low power consumption, a liquid crystal display device (LCD) has been used in wide field of applications such as finders of portable data terminals and video cameras and as display units of notebook PCs (personal computers). In order to decrease the cost, there has nowadays been widely used an LCD of the type of integrally forming the peripheral circuits of TFTs surrounding the display region while forming the thin-film transistors (TFTs) for driving the pixels in the display region. Polycrystalline silicon TFTs (p-Si TFTs) are used as the TFTs for driving pixels and as TFTs for the peripheral circuits in the LCD of the type of integrally forming the peripheral circuits.
The p-Si TFTs for driving the pixels must be fabricated in an LDD structure having a low density impurity implantation region (LDD—lightly doped drain region) formed among the channel region, a source region and a drain region to decrease the defective display caused by the leakage of current. The p-Si TFT for the peripheral circuit, on the other hand, is better not provided with the LDD region since provision of the LDD region results in a decrease in the operation speed and, besides, it is little affected by the leakage of current.
However, the n-ch TFT (TFT having n-type of electric conduction) without LDD region exhibits characteristics that are deteriorated due to hot carriers and, generally, exhibits lower reliability than that of the n-ch TFT having the LDD region. Through experiments conducted thus far, the present inventors have discovered that deterioration in the characteristics due to hot carriers can be decreased yet maintaining a sufficient operation speed of the TFTs upon employing a structure of providing the LDD region and covering the whole LDD region with the gate electrode (gate overlapping LDD structure, hereinafter referred to as GOLD structure). Concerning the TFT for driving the pixel, if there is employed a structure further provided with a conventional LDD region that is not covered with the gate electrode (hereinafter referred to as "partial GOLD structure") in addition to the GOLD structure, then, the off current can be decreased while achieving a high reliability. In the TFT of the GOLD structure, the LDD region as a whole is covered with the gate electrode while in the TFT of the partial GOLD structure, a portion neighboring the channel region in the LDD structure is covered with the gate electrode but other portions are not covered with the gate electrode.
Table 1 shows in comparison the characteristics and reliability of n-ch TFTs depending upon differences in the structure.
TABLE 1TFT1TFT2TFT3TFT4Type of conductionn-typen-typen-typen-typeLDD structurex∘xxGOLD structurexx∘xPartial GOLD structurexxx∘On-current∘∘∘∘∘∘Off-current∘∘∘∘∘∘Hot-carrier deteriorationxx∘∘High-speed circuitxx∘∘∘Pixelxxx∘
In Table 1, TFT1 represents an n-ch TFT of the non-LDD structure and of the non-GOLD structure, TFT2 represents an n-ch TFT of the LDD structure and of the non-GOLD structure, TFT3 represents an n-ch TFT of the GOLD structure and TFT4 represents an n-ch TFT of the partial GOLD structure. As shown in Table 1, the TFT3 of the GOLD structure and the TFT4 of the partial GOLD structure exhibit less deterioration due to hot carriers and higher reliability than those of the TFT1 and TFT2 of the non-GOLD structure. When the TFT3 is compared with the TFT4, the TFT3 is suited for the high-speed circuit (peripheral circuit) on account of its large on-current, but is not suited for driving the pixel due to its large off-current. The TFT4, on the other hand, has a slightly small on-current and a small off-current, and is suited for driving the pixel. The p-ch TFT (TFT having p-type of electric conduction) exhibits characteristics that are not almost deteriorated by hot carriers and needs not have the LDD region.
To lower the consumption of electric power, it is desired that the peripheral circuits are constituted by CMOS circuits. When the CMOS circuits are used, it is important to control the threshold value of the TFTs. In general, the p-Si TFT has a threshold voltage of a negative sign (smaller than 0 V). Therefore, the channel region must be doped with impurities of the p-type such as boron (B) at a low concentration (hereinafter also referred to as "channel doping"). The n-ch TFT and the p-ch TFT exhibit threshold voltages that are shifted in different amounts for the amount of boron with which they are doped. Therefore, to maintain a sufficient difference in the threshold value between the n-ch TFT and the p-ch TFT, the boron concentration in the channel region of the n-ch TFT should be set to be slightly higher than the boron concentration in the channel region of the p-ch TFT.
A method of manufacturing a conventional p-Si TFT substrate having an n-ch TFT of the partial GOLD structure (TFT for driving pixel), an n-ch TFT of the GOLD structure and a p-ch TFT (TFT for peripheral circuit) without LDD region will now be described with reference to FIGS. 32A to 41B. FIGS. 32A and 41B are sectional views of steps illustrating a conventional method of manufacturing the p-Si TFT. In FIGS. 32A to 41B, the region for forming the n-ch TFT (hereinafter also referred to as "first TFT") of the GOLD structure is illustrated on the left side in the drawings, the region for forming the n-ch TFT (hereinafter also referred to as "second TFT") of the partial GOLD structure is illustrated in the central portion of the drawings, and the region for forming the p-ch TFT (hereinafter also referred to as "third TFT") is illustrated on the right side in the drawings.
Referring, first, to FIG. 32A, a silicon nitride film (SiN film) 112, a silicon oxide film (SiO2 film) 114 and an amorphous silicon (a-Si) film are formed on the whole surface of the glass substrate 110 in this order. Then, the whole surface of the a-Si film is channel-doped with boron (B ions) and, then, the a-Si film is laser-crystallized by using an excimer laser to form a p-Si film 120. Referring next to FIG. 32B, a resist is applied onto the whole surface of the substrate followed by patterning by using the first photomask to thereby form a resist pattern 101M. The resist pattern 101M is so formed as to cover the whole region for forming the third TFT. Then, by using the resist pattern 101M as a mask, the p-Si film 120 is additionally channel-doped with boron except the region for forming the third TFT. Then, the boron concentration in the channel region of the n-ch TFTs (first and second TFTs) becomes slightly higher than the boron concentration in the channel region of the p-ch TFT (third TFT).
Referring next to FIG. 33, a resist is applied to the whole surface of the substrate and is patterned by using a second photomask to form resist patterns 102M. The resist patterns 102M are so formed as to cover the whole regions for forming the first to third TFTs. Then, the p-Si film 120 is etched by using the resist patterns 102M as masks to form island-like p-Si films 120a, 120b and 120c.
Referring next to FIG. 34, the resist is applied to the whole surface of the substrate and is patterned by using a third photomask to form resist patterns 103M. The resist patterns 103M are so formed as to cover a region that becomes the channel region of the first TFT, a region that becomes the channel region of the second TFT and the region for forming the third TFT. Then, by using the resist patterns 103M as masks, n-type impurities such as of phosphorus (P) are implanted at a low concentration. Then, n-type impurities are implanted into the p-Si film 121a on the region for forming the first TFT except the channel region 125a and into the p-Si film 121b in the region for forming the second TFT except the channel region 125b.
Referring next to FIG. 35A, an insulating film (gate insulating film) 130 and a first electrically conducting thin film 132 that serves as a gate electrode are formed in this order on the whole surface of the substrate on the p-Si films 121a, 125a, 121b, 125b and 120c. Referring next to FIG. 35B, the resist is applied to the whole surface of the substrate and is patterned by using a fourth photomask to form resist patterns 104M. The resist patterns 104M are so formed as to cover the channel region 125a of the first TFT and the p-Si film 121a of the region that becomes the LDD region, the channel region 125b of the second TFT and the p-Si film 121b of the region (GOLD region) covered with the gate electrode of the LDD region, and the region that becomes the channel region of the third TFT. Then, by using the resist patterns 104M as masks, the electrically conducting thin film 132 is etched to form the gate electrodes 132a 132b and 132c.
Referring next to FIG. 36, the resist is applied to the whole surface of the substrate and is patterned by using a fifth photomask to form resist patterns 105M. The resist patterns 105M are so formed as to cover the channel region 125b of the second TFT and the region that becomes the LDD region 123b, and the region where the third TFT is formed. Then, by using the resist patterns 105M and the gate electrode 132a as masks, n-type impurities such as of phosphorus are implanted at a high concentration. Then, there are formed a source region 122a and a drain region 124a of the first TFT, and a source region 122b and a drain region 124b of the second TFT.
Referring next to FIG. 37A, the resist is applied to the whole surface of the substrate and is patterned by using a sixth photomask to form resist patterns 106M. The resist patterns 106M are so formed as to cover the whole regions for forming the first and second TFTs. Then, by using the resist patterns 106M and the gate electrode 132c as masks, p-type impurities such as of boron are implanted at a high concentration. Then, a source region 122c and a drain region 124c are formed in the regions of the p-Si film 121c of the third TFT except the channel region 125c just under the gate electrode 132c. Next, the resist patterns 106M are peeled off, and the implanted impurities are activated by the irradiation with an excimer laser as illustrated in FIG. 37B.
Referring next to FIG. 38A, a first interlayer insulating film 134 is formed on the whole surface of the substrate on the gate electrodes 132a, 132b and 132c. Referring next to FIG. 38B, a resist is applied onto the whole surface of the substrate, and is patterned by using a seventh photomask to form resist patterns 107M. Then, by using the resist patterns 107M as masks, the interlayer insulating film 134 and the insulating film 130 are etched on the source regions 122a, 122b, 122c and on the drain regions 124a, 124b, 124c to form contact holes 136a, 136b and 136c.
Referring next to FIG. 39A, a second electrically conducting thin film 138 that serves as source/drain electrodes is formed on the whole surface of the substrate on the first interlayer insulating film 134. Referring next to FIG. 39B, a resist is applied to the whole surface of the substrate and is patterned by using an eighth photomask to form resist patterns 108M. Then, by using the resist patterns 108M as masks, the electrically conducting thin film 138 is etched to form source electrodes 138a, 138b, 138c and drain electrodes 139a, 139b, 139c. Through the above steps, there are formed an n-ch TFT (first TFT) of the GOLD structure illustrated on the left side in FIG. 39B, an n-ch TFT (second TFT) of the partial GOLD structure illustrated in the central portion of FIG. 39B and a p-ch TFT (third TFT) without LDD region illustrated on the right side in FIG. 39B.
Referring next to FIG. 40, a second interlayer insulating film 140 is formed on the whole surface of the substrate on the source electrodes 138a, 138b and 138c, and on the drain electrodes 139a, 139b and 139c. Then, by using a ninth photomask, the interlayer insulating film 140 is removed by etching on the source electrode 138b of the second TFT which is for driving the pixel to form a contact hole 142b.
Referring next to FIG. 41A, a third transparent electrically conducting film 144 that serves as pixel electrodes is formed on the whole substrate on the interlayer insulating film 140. Referring next to FIG. 41B, the electrically conducting film 144 is patterned by using a tenth photomask to form a pixel electrode 144b. Through the above steps, there is completed a p-Si TFT substrate including the n-ch TFT (TFT for driving the pixel) of the partial GOLD structure illustrated in the central portion of FIG. 41A, and n-ch TFT of the GOLD structure and p-ch TFT (TFT for peripheral circuit) without LDD region illustrated on the left side and on the right side in FIG. 41A.
When the n-ch TFTs of the GOLD structure and of the partial GOLD structure are formed as described above, it is not allowed to use the gate electrodes 132a and 132b as masks at the time of implanting n-type impurities at a low concentration into the p-Si films 121a and 121b except the channel regions 125a, 125b. Therefore, a step is newly required for forming the resist patterns 103M (see FIG. 34). Therefore, to form the CMOS circuits using the TFTs of the GOLD structure and of the partial GOLD structure, the step of photolithography is increased by at least one time as compared to when the TFTs of the non-GOLD structure are only used. To form the TFTs, therefore, eight or more times of photolithography steps are required. To manufacture the TFT substrate including the pixel electrode 144b, therefore, ten or more times of photo lithography steps are necessary resulting in a drop in the productivity of the TFT substrate and driving up the cost of manufacturing the TFT substrate.
Incidentally, the documents of the related art are as follows:
[Patent Document 1]
JP-A-2000-294787
[Patent Document 2]
JP-A-2001-13524

Thin-film transistor device, utilizing different types of thin film transistors


The present invention relates to an atomic scale electronic switch; wherein the position of one or more atoms or molecules is or are varied to control the state of the switch. The switch includes a plurality of fixed terminals approximately separated less than 100 .ANG.. Controlling the state of the switch is accomplished by applying a voltage or current to the terminals, thereby moving at least one atoms toward a desired terminal.

There is a continuing desire in the computer industry to increase the storage density of computer memory and build smaller electronic components for computers. Kazan et al., U.S. Pat. No. 4,826,732 issued May 2, 1989, discloses using a scanning tunneling microscope ("STM") to selectively remove or deposit a plurality of absorbate atomic particles from an absorbent carrier surface in an orderly fashion to record information. The STM can then be scanned over the same area again to readout the recorded information.
Eigler U.S. Pat. No. 4,987,312, issued Jan. 22, 1991, discloses moving an atom or molecule from one position on a substrate to another position on the substrate to record information and also repositioning atoms or molecules to fabricate a multi-atom structure. Copending application Ser. No. 07/569270, now U.S. Pat. No. 5,144,148, filed Aug. 17, 1990 is a CIP of and extends the teachings of this Eigler patent.
Foster et al., U.S. Pat. No. 4,916,688 issued Apr. 10, 1990 discloses reversibly changing selected areas of a data recording medium between amorphous and crystalline states with an STM to change the electronic properties of the medium at these areas.
Ooumi et al., U.S. Pat. Nos. 4,962,480 and 4,945,515, issued Oct. 9, 1990 and Jul. 31, 1990 respectively, disclose a memory device which involves writing on an atomic scale with an STM and then reading with the STM.
Although these techniques are useful, there still is a continuing need in the computer art for decreasing the size of computer electronic components and increasing the storage density of computer memory. The present invention provides an atomic scale electronic switch, an atomic scale memory device and an atomic scale logic circuit.
Other advantages of the present invention will become apparent from the following disclosure.


[Theme] To provide a monoclonal antibody against human GPR87. Also, to provide a novel means for diagnosing or treating a malignant tumor.

Malignant tumors (carcinoma, sarcoma and so on) are diseases which cause serious trouble with life maintenance of body and which have very high fatality rate when patients affect. In general they are classified by organs or tissues they develop from, into colon carcinoma, breast carcinoma, gastric carcinoma, lung carcinoma and bone sarcoma, for example. Histologically they are classified into adenocarcinoma, squamous cell carcinoma, transitional cell carcinoma, anaplastic carcinoma and so on.
Efficacious techniques for diagnosis and treatment against various types of malignant tumors have been developed by each research institution and the like. But valid techniques for diagnosis and treatment are not established in many cases.
Squamous cell carcinoma is a cancer which cells of squamous epithelium or squamous metaplasia are changed into malignant tumors. It appears at buccal cavity, tongue, vocal cord, esophagus, tracheobronchial region, lung, pharynx, larynx, female valuva, vagina, cervix, vaginal portion, skin, anus and so on. It occurs comparatively with increased frequency. For example, about 30% of lung carcinomas and about 90% of esophageal carcinomas are squamous cell carcinomas. Also about 80% of uterine carcinomas are cervical carcinomas and most of them are squamous cell carcinomas.
Transitional cell carcinoma is a cancer which cells derived from transitional epithelia tissues changed into malignant tumors. It appears at renal pelvis, urinary duct, bladder and so on.
Adenocarcinoma is a cancer which cells derived glandular tissues changed into malignant tumors. It appears at lacteal gland, stomach, colon, lung, gall bladder, bile duct, kidney, prostate, duodenum, pancreas, ovary, uterus, vagina and so on.
In skin cancer, basal cell carcinoma, squamous cell carcinoma and melanoma in turn appear with increased frequency. In head and neck cancer, most of tongue cancers are squamous cell carcinomas, in pharynx cancer, squamous cell carcinoma and malignant lymphoma appear with increased frequency, and most of larynx cancers are squamous cell carcinomas. In lung cancer, adenocarcinoma, squamous cell carcinoma, small cell carcinoma in turn appear with increased frequency. Most of esophaus cancers are squamous cell carcinomas, most of gastric cancers and colon cancers are adenocarcinomas, and most of pancreas cancers are tubular adenocarcinomas. Most of uterus cancers are adenocarcinomas, most of cervix cancers are squamous cell carcinomas, and most of breast cancers are adenocarcinomas. In kidney cancers, renal cell carcinomas (adenocarcinomas) and renal pelvis-ureter carcinomas (transitional cell carcinomas) in turn appear with increased frequency. Most of bladder cancers are transitional cell carcinomas and part of them are squamous cell carcinomas.
Each cancer is diagnosed by histopathological examination (biopsy, cytodiagnosis, tissue diagnosis, etc), CT (computerized tomography), PET (positron emission tomography), endoscopical ultrasonography and so on. However it is preferable to establish more accurate diagnostic techniques, for example, in regard to detection of with or without invasion and metastasis, and clarity of the cancerous or noncancerous boundaries. Also, operative therapy, chemical therapy or radiation therapy are treated for patients of each squamous cell carsinomas, but sufficient therapeutic effects have not been obtained in many cases.
GPCRs (G-protein-coupled receptors) are membrane proteins with seven transmembrane domeins, and are estimated to constitute a superfamily of nearly 1,000. Their ligands are diverse, for example, exogenous stimulations (lights, smells, tastes, pheromone, etc), lipids, hormones, autacoid, neurotransmitters, nucleotides and so on. In addition, it is thought that more than half of the drugs that are currently available act on GPCR.
GPR87 (G protein-coupled receptor 87) is a protein belonging to the GPCR family, its gene has homology with some of the P2Y receptor, but its function and other knowledge are poorly understood. In non-patent document 1, it was reported that the GPR87 gene has been identified by EST data mining. In non-patent document 1, it was reported that the ligand of GPR87 is lysophosphatidic acid.
It is known by microarray analysis that GPR87 has relatively high expression at the RNA transcriptional levels in skin and placenta of normal human tissues, in small airway epithelial cells, tracheal bronchial epithelial cells, epidermal keratinocytes and human prostate epithelial cells of normal human cells, in lung carcinomas (squamous cell carcinomas) and pancreatic carcinomas of cancer tissues, and cell lines derived from human esophageal carcinoma, cell lines derived from human gastric carcinoma, cell lines derived from human pancreatic carcinoma, cell lines derived from human lung carcinoma, cell lines derived from human ovarian carcinoma, and cell lines derived from human cervical carcinoma of carcinoma's cell lines.
In non-patent document 3, it was reported that GPR87 expresses highly in lung squamous cell carcinoma. In non-patent document 4, it was reported that GPR87 expresses in lung squamous cell carcinoma, lung adenocarcinoma, head and neck carcinoma, pharynx squamous cell carcinoma, larynx squamous cell carcinoma, skin squamous cell carcinoma and cervical squamous cell carcinoma, and it may contribute to viability of human tumor cells.
In patent document 1, GPR87 expression profiles obtained by real-time PCR are disclosed. In addition, the document mentions GPR87 monclonal antibodies, its chimeric antibodies, single chain antibodies and so on, however the actual establishment of hybridomas producing monoclonal antibodies has not been disclosed.
In patent document 2, the anti-GPR87 antibodies for the treatment of cancer are disclosed. In addition, the document mentions GPR87 monclonal antibodies, its modified antibodies, its chimeric antibodies, its humanized antibodies and so on, however only rabbit polyclonal antibodies have been produced and used by them, and the actual establishment of hybridomas producing monoclonal antibodies has not been disclosed.
To date, the anti-GPR87 antibody are sold by Acris Antibodies GmbH (German), Abcam, Inc. (UK), LifeSpan Biosciences, Inc. (USA), Novus Biologicals, LLC (USA), Thermo Fisher Scientific, Inc. (USA), MBL International Corporation (USA), Gene Tex, Inc. (USA), Genway Biotech, Inc. (USA), United States Biological (USA), Imgenex Corporation (USA) and so on. Some of these antibodies were used in the experiments mentioned in non-patent document 3 and non-patent document 4. However these antibodies are all rabbit polyclonal antibodies. To date, it is not reported that GPR87 monoclonal antibodies are actually created.
In non-patent document 5, it has been described about DNA immunization. In non-patent document 6 and 7, it has been described about examples of methods for producing monoclonal antibodies. In non-patent document 8, it has been described about chimera antibodies. In non-patent document 9, it has been described about humanized antibodies. In non-patent document 10 and 11, it has been described about scFv. Non-patent document 5-11 are incorporated into this application by reference. Citation of these documents is not an admission that any particular reference is prior art to this invention.
[Patent Document 1]
    WO2004/082572[Patent Document 2]    WO2008/031842[Non-Patent Document 1]    T. Wittenberger et al, "An Expressed Sequence Tag (EST) Data Mining Strategy Succeeding in the Discovery of New G-Protein Coupled Receptors"; J. Mol. Biol. (2001) 307, 799-813[Non-Patent Document 2]    K. Tabata et al, "The orphan GPCR GPR87 was deorphanized and shown to be a lysophosphatidic acid receptor"; Biochemical and Biophysical Research Communications 363 (2007) 861-866[Non-Patent Document 3]    M. Gugger et al, "GPR87 is an overexpressed G-protein coupled receptor in squamous cell carcinoma of the lung"; Disease Markers 24 (2008) 41-50[Non-Patent Document 4]    S. Glatt et al, "hGPR87 contributes to viability of human tumor cells"; Int. J. Cancer 122, 2008-2016 (2008)[Non-Patent Document 5]    K. K. Peachman et al, "Immunization with DNA through the skin"; Methods 31 (2003) 232-242[Non-Patent Document 6]    G. Galfre and C. Milstein, "Preparation of Monoclonal Antibodies: strategies and Procedures"; Methods in Enzymology 73 (1981) 3-46[Non-Patent Document 7]    St. Groth et al, "Production of Monoclonal Antibodies: Strategy and Tactics"; Journal of Immunological Methods 35 (1980) 1-21[Non-Patent Document 8]    S. L. Morrison et al, "Chimeric human antibody molecules: Mouse antigen-binding domains with human constant region domains"; Proc. Natl. Acad. Sci. USA 81 (1984) 6851-6855[Non-Patent Document 9]    M. Verhoeyen et al, "Reshaping human antibodies: Grafting an antilysozyme activity"; Science 239 (1988) 1534-1536[Non-Patent Document 10]    R E Bird et al, "Single-chain antigen-binding proteins" Science 242 (1988) 423-426[Non-Patent Document 11]    J. S. Huston et al, "Protein engineering of antibody binding sites: recovery of specific activity in an antidigoxin single-chain Fv analogue produced in Escericia coli"; Proc. Natl. Acad. Sci. USA 85 (1988) 5879-5883

Abstract: [Solution means] Monoclonal antibodies against human GPR87 are provided. The antibodies can recognize human GPR87, which is expressed on a cell membrane while retaining a three-dimensional structure, and can recognize GPR87, which is expressed in a cell endogenously with an epitope being present in an extracellular domain of full-length human GPR87. The antibodies are thus useful in biochemical analysis, etc., of GPR87, useful in immunohistological diagnosis, etc., of squamous cell carcinoma, and also potentially useful in PET diagnosis, antibodies for treatment, etc., of squamous cell carcinoma.


The invention relates to an electrode assembly for the electrochemical treatment of liquids with a low conductivity. Said assembly comprises electrodes (1, 2), between which a polymer solid electrolyte (3) is situated. The electrodes are pressed against one another by means of a compression device (9, 10; 91) and are configured in such a way that the assembly can be traversed by the liquid. To produce said assembly simply and to ensure that it is flexible and easy to use, the compression device (9, 10; 91) is supported on the electrodes (1, 2).

A main area of use for such an electrode assembly is in water systems in which pure water or ultrapure water is to be sterilized and rendered free of algae, in particular. In this case, the water system may comprise pipelines, collection tanks, open baths etc.
Electrode assemblies of the type mentioned initially are used, in particular, to disinfect rainwater, to disinfect ultrapure water circuits in the semiconductor industry and pharmaceuticals industry, to remove organic pollutants in rinse water, to purify water for the food industry and cosmetics industry, and in all types of industrial cooling-water circuits in order to prevent the growth of algae or the growth of bacteria or, in the case of high levels of contamination, to reduce the latter.
Such an electrode assembly can be used to generate oxidizing agents which oxidize germs and thus destroy or inactivate them.
The electrochemical generation of oxidizing agents has the advantage that it is possible, in principle, to adapt to the respective application. A large amount of oxidizing agent is thus required when a water system has already been contaminated with algae or biologically affected and is intended to be purified and disinfected. In contrast, once this operation has been concluded, the water system can be permanently kept in the disinfected and purified state, for which only a small amount of oxidizing agent is required from time to time.
A varying amount of oxidizing agent is also required when a water system has a high organic load as a result of an accident. A similar situation applies to the operation of filling a tank, in which a high level of oxidizing agent production is initially required in order to effect initial disinfection, while only relatively small amounts of oxidizing agent are then sufficient to maintain the disinfected state.
In principle, electrochemical methods are suitable for satisfying the different demands imposed on the production of oxidizing agents since the production of oxidizing agents can be controlled by supplying current.
In order to treat liquids with a low conductivity, for example ultrapure water, it is necessary, on account of the high resistance of the water, to use high voltages in order to generate the current densities required for the production of the oxidizing agents. This problem is partly solved by using polymeric solid electrolytes which, preferably in the form of a membrane having a thickness of a few tenths of a millimeter to a few millimeters, bridge the gap between the electrodes on the basis of their ion conductivity and are suitable as an interlayer between the electrodes in order to avoid a short circuit. On account of the relatively good ion conductivity of the polymeric solid electrolyte, the electrical potential of one electrode is brought very close to the other electrode, a film of water which is thus exposed to high current densities being situated between the surface of the polymeric solid electrolyte and the directly adjacent electrode.
Such electrode assemblies have been implemented for decades in the same manner in principle using the design of a "Fischer cell". In this case, a pressure-exerting device which is formed from a surrounding housing is used to press the flat electrodes flat against the membrane which is situated between the electrodes and comprises a polymeric solid electrolyte. A sufficient contact pressure is produced by screwing flat pressure plates of the housing, which must take place with a minimum torque.
On account of the high level of required stability of the pressure plates of the housing, the construction of such a cell is high and necessitates involved handling. In addition, adaptation to higher throughputs is problematic since the effective electrode area of the cell would have to be enlarged for this purpose or the flow of liquid would have to be divided up and passed through a plurality of cells.
The Fischer cells were originally constructed using lead oxide electrodes. In this case, the use of a lead oxide anode has the further disadvantage that the electrode decomposes in water if it is not held at a protective potential. The use of an electrode assembly having a lead oxide anode is therefore possible only during continuous operation, with the result that the option of using the corresponding cell only when required does not apply.
DE 100 25 167 A1, for example, discloses the practice of using an electrode through which a liquid can flow on account of numerous groove-shaped channels and which has a surface comprising a doped diamond layer. Such electrodes have likewise been arranged in a cell constructed like a Fischer cell (cf. DE 295 04 323 U1). The associated handling disadvantages have been accepted for decades by those skilled in the art as being unalterable.

Electrode assembly for the electrochemical treatment of liquids with a low conductivity


A straw assembly has a flexible first segment with at least one longitudinal glide ridge extending inwardly from a drinking end thereof, a retaining shoulder at a fixed distance from the drinking end, and an orienting finger extending from the retaining shoulder.

A variety of reusable straw assemblies are known in the art for use in drinking cups. Flexible elastomeric straws made of various materials, such as silicone, have been used, as have two piece straw assemblies. The latter typically consist of a lower straw mounted on the underside of a lid and an upper straw mounted on the top of a lid, to form an integral straw assembly. Straws having various elements preventing their accidental removal from the cup, such as lips, collars on the outside of the cup lid, and the like, are also known.
Nonetheless, most of these designs are laborious and time-consuming to assemble, difficult to clean, and of limited durability.
The art has also failed to provide a straw assembly optimally suited for use in a spillproof drinking cup of the type disclosed in U.S. Pat. No. Des. 366,809 to Green or U.S. Pat. No. 5,273,172 to Rossbach et al., which are licensed to the assignee of the present invention. These cup assemblies include a cup, a threaded or snap-on lid, a hole through the lid to accept a straw, and a cap mounted on the lid and rotatable about a horizontal axis to fold, seal and enclose the protruding top of the straw.
A typical disposable plastic straw could be used in these cup assemblies. The drawbacks of such a straw are evident. The plastic would rapidly be weakened and split by the bending motion required in the sealing cap. A standard straw would have to be cut to fit the dimensions of the cup and sealing cap. Furthermore, a standard straw would tend to slip and rest directly on the bottom of the cup, limiting the suction action of the straw. In addition, the straw could be difficult to insert through the hole in the lid without bending and buckling. The sealing action of these cups also would be limited by the thin, semi-rigid walls of the straw. Only a partial seal would be effected.


In a method for locating an arterial constriction and performing an arteriotomy distally thereof, especially with a view to establishing a bypass connection between the aorta (52) and a part of the coronary artery (51) distally of a constriction in the artery, the most important steps are locating the site of the constriction in the artery (51), preferably by using an instrument (9) with a head (3) carrying an ultrasonic transducer array (not shown), and making an incision in the artery (51) closely distally of the constriction, preferably by using a knife (not shown) placed in said head (3).

Modern heart surgery was developed fundamentally in the nineteen-fifties together with the extra-corporeal circulation, based on the use of the heart-and-lung machine, making it possible to replace heart valves and to correct certain congenital heart disorders; this as a whole was designated "open heart surgery", as the heart itself, its ventricles and internal functional parts were opened during the operation.
As a natural extension of this method, the coronary bypass surgery emerged in the mid-sixties, also based on the use of the same per-operative technology, viz. the heart-and-lung machine. In this case the surgeon, although not having to operate within the heart itself, needed peace to work in the operating field, i.e. the "coronary tree", the heart's own circulatory system, substantially embedded in the surface of the heart in the form of two main stems--right and left--gradually branching out down along the heart, finally to end deep below the surface in the form of the end-arterial branches of the heart musculature.
Thus, the techniques already established by the use of the heart-and-lung machine were taken over directly, although the coronary bypass operation could not be categorized as "open heart surgery", but rather as "closed heart surgery"--simply to have peace and quiet in the operating field.
The use of the heart-and-lung machine involves a trauma to the heart itself, and more or less serious complications will often appear post-operatively, during intensive care as well as later; thus, in short, a so-called post-perfusion syndrome has been described.

Method and instrument for establishing the receiving site of a coronary artery bypass graft


Devices, systems and methods for communications that include social media clients are provided. In particular, a server operates a virtual client for communicating with clients of a social media server. The server receives a call request associated with a directory number of a call server, the call request to initiate a call associated with the directory number and a given client of the social media server. The server conducts the call by controlling: the virtual client to communicate with the given client, via the social media server; and the virtual client to communicate with a communication device associated with the directory number, via the call server. The server may also facilitate exchange of status updates between a given client of the social media server and the call server. The server may also facilitate calls between respective clients of different social media servers.

Communications using internet-based applications (e.g. "apps") and/or social media clients to message a friend and/or place a telephone call (e.g. and avoid cellular charges or costs associated with landlines) are becoming ubiquitous. Similar packet-based communication techniques including VoIP (Voice over Internet Protocol) calls may be placed over the internet using clients embedded within a website accessed via a personal computer and/or laptop, and the like. However, internet voice-call users are generally not accessible from within a business communications system such as an enterprise business (or cloud) network application, which may depend on landlines and/or cellular networks. A similar situation may exist for users (such as consumers) who use landlines or cell phones, but who don't have access to social media applications. Yet another similar situation may exist for users (such as consumers) who use social media applications for calling, but who are unable to call landlines or cell phones and/or communication devices services by a local area network, and the like, for example in a business communication system.
It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of illustrated embodiments of the present specification.

This patent is subject to a terminal disclaimer.


A reel driving apparatus and a magnetic recording and reproducing device including the reel driving apparatus, where the reel driving apparatus includes: a driver including at least a portion protruding under a deck chassis; a power transmitting unit transmitting a power to the driver; a power changing unit gearing with the driver and selectively transmitting a power to a plurality of reel tables according to a direction along which the driver rotates; and a fixing unit supporting the driver.

1. Field of the Invention
The present invention relates to magnetic recording and reproducing devices such as video tape recorders (VTR) and camcorders. More particularly, the present invention relates to a reel driving apparatus for rotating a reel table on which reels of a tape cassette are placed and a magnetic recording and reproducing device having the same.
2. Description of the Related Art
In general, a magnetic recording and reproducing apparatus such as a VTR and a camcorder includes a reel driving apparatus for rotating reels of a tape cassette to supply a magnetic tape to and withdraw the magnetic tape from a head drum. Such a reel driving apparatus selectively transmits power of a capstan motor to a supplying and winding reel table on which supplying and winding reels of a tape cassette are placed to facilitate travel of a magnetic tape along a predetermined path forward or backward.
FIGS. 1 and 2 are schematic views of a magnetic recording and reproducing device including a conventional reel driving apparatus.
The magnetic recording and reproducing device includes a head drum 11, supplying and winding reel assemblies 12 and 13, and a capstan motor 17. The head drum 11 records an image and sound information on and/or reproduces an image and sound information from a magnetic tape and is installed on an upper surface of a deck chassis 10. The supplying and winding reel assemblies 12 and 13 are spaced apart from each other on a lower portion of the upper surface of the deck chassis 10 and respectively include supplying and winding reel tables 12a and 13a on which supplying and winding reels of a tape cassette are placed. The capstan motor 17 is installed in the vicinity of the head drum 11, transmits power to the supplying and winding reel assemblies 12 and 13, and includes a capstan shaft 17a for transferring the magnetic tape together with a pinch roller 18.
A reel driving apparatus 1 is installed between the supplying and winding reel assemblies 12 and 13 and the capstan motor 17 to transmit the power of the capstan motor 17 to the supplying and winding reel assemblies 12 and 13.
The reel driving apparatus 1 includes a capstan gear 19 gearing with a motor gear 17b of the capstan motor 17, a driving gear 14 including a driven pulley 14a coupled to a driving pulley 19a of the capstan gear 19 by a power transmitting belt 16, and an idle gear 15 selectively gearing with a supplying real gear 12b of the supplying reel assembly 12 or a winding reel gear 13b of the winding reel assembly 13 according to a direction along which the driving gear 14 rotates.
The power of the capstan motor 17 is transmitted through the capstan gear 19 and the power transmitting belt 16 to the driving gear 14. The power transmitted to the driving gear 14 is transmitted to the supplying reel gear 12b or the winding reel gear 13b through the idle gear 15 revolving around a driving shaft 21 of the driving gear 14 according to the direction along which the driving gear 14 rotates.
However, in the reel driving apparatus 1 having the above-described structure, the power transmitting belt 16 is installed on the upper surface of the deck chassis 10. Thus, a space for installing the other deck components such as a pole base assembly (not shown), a pinch roller assembly (not shown), or the like disposed on the upper surface of the deck chassis 10 is reduced. As a result, the structure of the deck chassis 10 becomes complicated, and it is difficult to make the deck chassis 10 compact.
To solve this problem, as shown in FIG. 3, there is suggested a reel driving apparatus 1′ including a motor gear 17b′ of a capstan motor 17, a capstan gear 19′ including a driving pulley 19a′, a power transmitting belt 16′, and a driven pulley 14a′ of a driving gear 14′ that are disposed on a lower surface of the deck chassis 10.
In the reel driving apparatus 1′, a plurality of components are disposed on the lower surface of the deck chassis 10 to increase a space for installing the other components disposed on the upper surface of the deck chassis 10. However, the driving gear 14′ protrudes upward from the driving shaft 21 fixed to a stationary bracket 20 depressed from the deck chassis 10 downward by a thickness of the driven pulley 14a′. Thus, when the reel driving apparatus 1′ is assembled, it is difficult to insert the power transmitting belt 16′ between the driving pulley 19a′ and the driven pulley 14a′.
In other words, the power transmitting belt 16′ is assembled as follows. The driving gear 14′ is fixed to the driving shaft 21 of the stationary bracket 20 on the upper surface of the deck chassis 10. Next, an end of the power transmitting belt 16′ is inserted into the driven pulley 14a′ of the driving gear 14′, and the other end of the power transmitting belt 16′ is pushed under the deck chassis 10 through a space 24 between the deck chassis 10 and the stationary bracket 20. Thereafter, the deck chassis 10 is turned upside-down to insert the other end of the power transmitting belt 16′ into the driving pulley 19a′ of the capstan gear 19′. However, when the deck chassis 10 is turned upside-down to insert the other end of the power transmitting belt 16′ into the driving pulley 19a′ of the capstan gear 19′, the end of the power transmitting belt 16′ may deviate from the driven pulley 14a′ or the other end of the power transmitting belt 16′ may come out of the space 24 between the deck chassis 10 and the stationary bracket 20. In this case, a worker must turn the deck chassis 10 upside-down to insert the end of the power transmitting belt 16′ into the driven pulley 14a′ or push the other end of the power transmitting belt 16′ under the deck chassis 10 through the space 24 between the deck chassis 10 and the stationary bracket 20.
As described above, when the power transmitting belt 16′ is assembled, the upper and lower surfaces of the deck chassis 10 must be turned upside-down. Also, when the end of the power transmitting belt 16′ deviates from the driven pulley 14a′ during turning of the deck chassis 10, the power transmitting belt 16′ must be re-assembled from the start.
In addition, the reel driving apparatus 1 or 1′ has a structure in which the idle gear 15 revolves according to the direction along which the driving gear 14 or 14′ rotates on the upper surface of the deck chassis 10. Thus, the idle gear 15 may contact or interfere with the upper surface of the deck chassis 10 due to a manufacturing tolerance or the like. In a case where the idle gear 15 contacts or interferes with the upper surface of the deck chassis 10, noise is made between the idle gear 15 and the deck chassis 10. Also, the power of the capstan motor 17 may not be transmitted to the supplying reel gear 12b of the supplying reel assembly 12 or the winding reel gear 13b of the winding reel assembly 13.

Reel driving apparatus and magnetic recording and reproducing device having the same


A routing method. When implemented in a network system, the routing method ameliorates problems of media stream routing through a network address translation (NAT) device. First, whether a first terminal will correspond to different public address-and-port information for receiving media stream packets from a second terminal opposite to the first terminal after receiving different requests is determined. The first and second terminals comprise a caller and a callee which are capable of communicating in SIP protocol. The public address-and-port information is recorded as source information in media stream packets initiated by the requests. Media stream packets from the first terminal are relayed based on the determination.

1. Field of the Invention
The present invention relates to a session initiation protocol (SIP), and in particular to a routing method which may conform to standard SIP specification, wherein real-time transport protocol (RTP) packets can pass through network address translation (NAT) devices and be routed correctly.
2. Description of the Related Art
A private address and a port number of a network device in a local area network (LAN) with a network address translation (NAT) device are translated to a public address and a public port number by the NAT device when communicating with another network device external to the LAN. In standard session initiation protocol (SIP), a session description protocol (SDP) message record an actual address and a port number, i.e. a private address and a port number, of a source communication terminal transmitting the SDP messages. On the other hand, when receiving the SDP message, another communication terminal opposite the communication terminal transmits real-time transport protocol (RTP) packets based on the source address and port number recorded in the received SDP message. Hence, if the source address and port number recorded in the SDP messages are a private address and private port number, the RTP packets will be incorrectly routed.
Several methods have been adopted to solve the above-mentioned problem of RTP packet routing. For example, in one method, a SIP server which can be referred to in document RFC 2543 or RFC 3261, published by the Internet Engineering Task Force (IETF), relays all RTP packets of a caller and a callee to ensure correct RTP packet routing. This method, however, places a heavy relay work load on the SIP server.
In method of Application Level Gateway (ALG) and Firewall Control Protocol (FCP) methods, NAT devices translate private source addresses and port numbers of outgoing SDP messages transmitted from an internal to an external network into public addresses and port numbers. NAT devices conforming to ALG and FCP, however, are required by the method while other NAT devices do not work.
In the Simple Traversal of UDP through NATs (STUN) or Traversal Using Relay NAT (TURN) methods, a NAT device is provided with a server for notifying internal terminals of public addresses and port numbers correspond thereto. An internal terminal acquires a public address and port number, from the server of a NAT device, as source address and port number in an SDP message. This method, however, requires additional servers, and communication terminals are required to support the STUN or TURN protocol. Additionally, there is a still high probability that RTP packets will be relayed by a SIP server. Hence, SIP servers are still placed with a heavy relay work load.
In the universal plug and play (UPnP) method, communication terminals acquire public addresses and port numbers from NAT devices, as source addresses and port numbers recorded in SDP messages. Terminals and NAT devices, however, must support the UPnP protocol in addition to SIP.
In still another method, the NAT device type is detected using standard SIP messages to overcome the previously described problem of RTP packet routing. In the method, NAT devices are categorized into full cone, restricted cone, port restricted cone or symmetric NAT devices. This method, however, cannot work correctly with other NAT devices excluded from the four NAT device categories.
In summary, additional resources are required in the above-described methods, such as NAT devices supporting ALG, and NAT devices provided with additional servers or additional protocols. Alternatively, NAT devices are required to satisfy four NAT device categories. Hence, the conventional methods are only capable of working effectively with SIP systems with the provision of additional resources and typical NAT devices.
Hence, there is a need for a new method capable of solving the problems presented by the conventional methods.

Routing method and SIP server using the same


A semiconductor device is provided. An isolation structure is formed in a substrate to define a first and a second active region, and a channel active region therebetween. A field implant region is formed below a portion of the isolation structure around the first, second, and channel active regions. A channel active region includes two first sides defining a channel width. The distance from each first side to a second side of a neighboring field implant region is d1. The shortest distance from a third side of each first or second active region to an extension line of each second side of the field implant region is d2. R=d1/d2, where 0.15≦R≦0.85. A gate structure covers the channel active region and extends over a portion of the isolation structure. Source/drain doped regions are formed in the first and the second active regions.

1. Field of the Invention
The present invention relates to an integrated circuit, and more particularly to a semiconductor device.
2. Description of Related Art
MOS devices are widely used semiconductor devices. As the sizes of devices are gradually reduced, channel lengths are reduced, which accelerates the operation speed of MOS transistors, and meanwhile aggravates a short channel effect. Based on a formula of Electric field=Voltage/Length, if an applied voltage remains unchanged, and the channel length of a transistor is reduced, the energy of electrons in the channel will be increased under the acceleration of the electric field, thus resulting in more frequent electrical breakdown phenomena. The increase of intensity of the electric field may enhance the energy of electrons in the channel, which also results in the electrical breakdown.
Generally speaking, the breakdown voltage of a high voltage device happens earlier since the potential crowding phenomenon happens earlier on a surface of a side close to the drain region, such that it is difficult to raise the breakdown voltage. The conventional high voltage device increases the distance between a source/drain region and a gate region so as to reduce a transverse electric field in the channel by the use of an isolation structure. Moreover, the field implant region formed below the isolation structure may achieve a channel stop function, thereby improving the effect of breakdown voltage of the device.
FIG. 1 is a schematic cross-sectional view of a MOS device. Referring to FIG. 1, in order to raise the breakdown voltage of the device, a field implant region 112 is usually formed below the isolation structure 102. However, since the formed field implant region 112 usually not only is located below the isolation structure 102, but also extends upwards to be neighboring to the channel region 104. When the MOS device is applied in a high voltage, the voltage difference between the substrate 100 and the gate 124 is large. When a certain voltage difference is reached, the channel region 104 is inversed. The formed inversion layer and the field implant region 112 may form a PN junction, thus causing a severe leakage current.


This invention relates to a color image forming apparatus which is capable of forming a mono-color image based on the color image input data. The apparatus includes a circuit for determining the highest value of the image input data. This circuit is called the highest value image data outputting circuit. The highest input color data value is found by comparing the values of the image data for the three primary colors (yellow, magenta and cyan) and outputting the value for the color having the highest input value. The apparatus further includes a mono-color image forming portion which forms a mono-colored image based on the output of the highest value image data outputting circuit.

1. Field of the Invention
The present invention relates to a color image forming apparatus, and more particularly, to a color image forming apparatus having a function of forming a mono-color image based on full-color image data.
2. Description of the Prior Art
Many color image forming apparatuses are provided with not only a function of forming a full-color image based on full-color image data which is a primary function thereof, but also a function of forming a mono-color image based on the full-color image data.
Full-color image data comprising red (R), green (G) and blue (B) signals of three primary colors of light is converted into full-color image data comprising yellow (Y), magenta (M) and cyan (C) signals of three primary colors of image &/rming material such as toner. In a color image forming apparatus, of the three primary color signals, a magenta signal is often used in forming a mono-color image based on the full color image data. This is because of the fact that it is considered that the luminosity of the human eye is sensitive to a color component of green.
As described above, in the conventional color image forming apparatus, a mono-color image is formed based on only the signal data of one color. In this case, there is hardly any problem when an original includes green images. However, for images of colors other than green, the density of the mono-color image formed is low which causes the image to be weak in color since yellow and cyan signal data are not used. In an extreme case, a defective image is formed.

Color image forming apparatus having mono-color image forming function


The present invention provides a flip-flop diagonal with variable viewing angles. It comprises a housing body, an eyepiece adapter unit and a reflective mirror unit. The housing body has a cylindrical sleeve for mounting the diagonal to a telescope. The eyepiece adapter unit includes an eyepiece adapter and an eyepiece support frame, the eyepiece adapter is fixed on the eyepiece support frame, the eyepiece support frame is pivotably mounted on the housing body. The reflective mirror unit includes a reflective mirror, a mirror support bracket and rotary shafts, the reflective mirror is mounted in the mirror support bracket, and the mirror support bracket is pivotally mounted on the eyepiece support frame through the rotary shafts. With the flip-flop diagonal according to the present invention, when observing the sky through the refracting astronomical telescope, wherever the target is, the eyepiece can be located in different positions only by changing the angles of the eyepiece adapter. Therefore, the number of the telescope accessories can be reduced, and, on the other hand, the observation is more convenient.

When people perform astronomy observation, the position of the celestial target often rotates with respect to the refracting astronomical telescope. Therefore, the current refracting telescopes need to be equipped with a certain accessory, i.e., diagonals, which could change the optical axis orientation, thus will facilitate the observers' viewing celestial targets in different positions. At present, two kinds of diagonals with fixed angle are commonly used. One is 45°, the other is 90°, which could turn the optical axis by 45° or 90° for convenient observation. Since the viewing angle is fixed, the whole diagonal has to be changed if the observers want to change the observation angle, which will cause the problems of redundant accessories and wasting time to re-aim the target.


A wiring structure thereof includes a first interlayer insulating film, a first wiring and a first electrode for the capacitive element embedded in the first interlayer insulating film, a barrier insulating film formed over the first interlayer insulating film to cover the wiring and the electrode, a second interlayer insulating film formed over the barrier insulating film, and a second wiring and a second electrode for the capacitive element embedded in the second interlayer insulating film. The lower surface of the second wiring is positioned in the middle of the thickness of the second interlayer layer film, and the lower surface of the second electrode is in contact with the barrier insulating film. The barrier insulating film of a portion interposed between both electrodes functions as a capacitance insulating film of the capacitive element and is thicker than the barrier insulating film of a portion covering the first wiring.

The present invention relates to a semiconductor device and a manufacturing method therefor, and is available suitably in, for example, a semiconductor device having a capacitive element and a manufacturing method therefor.
Various semiconductor devices are manufactured by forming a MISFET (Metal Insulator Semiconductor Field Effect Transistor), a capacitive element and the like over a semiconductor substrate and coupling among the respective elements by wirings. As the capacitive element formed over the semiconductor substrate, there may be mentioned a MIM (Metal Insulator Metal) type capacitive element.
There has been described in each of Japanese Unexamined Patent Application Publication No. 2005-109063 (Patent Document 1), Japanese Unexamined Patent Application Publication No. 2004-214550 (Patent Document 2), and Japanese Unexamined Patent Application Publication No. 2004-128466 (Patent Document 3), a technique related to the MIM type capacitive element.

Semiconductor device and manufacturing method therefor


Method and computer system for logically evaluating a Boolean expression used in a query statement to optimize the query. The Boolean expression refers to an attribute and includes a plurality of conditions. The Boolean expression is received (410) and decomposed (420) into the plurality of conditions. For each condition at least one condition value referring to the attribute is extracted (421) from the condition. The at least one condition value is then inserted (422) into a condition value list in sorted order. A relationship vector of the at least one condition value is initialized (423). Then the relationship vectors of the at least one condition value and of each further condition value that is in the condition list and that is in the value range of the condition are adjusted (424). After having processed all conditions the Boolean expression may be reducing (430) according to each relationship vector.

Some applications provide query interfaces that allow a user to define Boolean expressions that include multiple conditions for selecting data from a computer system, such as a database system or a file system. For example, the Boolean expressions can be written in a standard query language (SQL). They are then sent to the computer system, where they are executed. Examples of such a computer system are described in the patent applications WO 02/061612 and WO 02/061613. A Boolean expression can include multiple conditions which are combined by Boolean operators. A condition typically includes an attribute name, an operator, and a value or a value range.
For example, the following three conditions referring to the attribute birth_date may be combined with AND or OR operators.
birth_date between 1938 and 1990
birth_date <=1940
birth_date >1920
Advantageously, within the system the complete Boolean expression is processed in disjunctive or conjunctive normal form. In this example, it is assumed that all conditions are combined with a Boolean AND or that all conditions are combined with a Boolean OR. If there are many conditions in the Boolean expression, it may happen intentionally or unintentionally that some of the conditions refer to the same attribute.
Some combinations of conditions referring to the same attribute may either lead to uninteresting results for logical reasons or cause more conditions than necessary to be passed to the computer system. The following cases may be distinguished:
Null set: The result set is empty (zero records found). This may happen if all the conditions are combined with AND.
Entire search domain: The result set consists of all records loaded into or stored in the computer system, so the selectivity is zero. This may happen if the conditions are combined with OR.
More conditions than necessary: two or more of conditions referring to the same attribute have an overlap with respect to their selectivity. That is, there is some redundancy in the conditions of the Boolean expression.

Method and system for Boolean expression query optimization


A hair replacement device which includes a hair attachment flap hingedly attached to the interior of the base and along its perimeter. A plurality of perforations are formed into the hair attachment flap where the preferred perforations are slits which may be shaped like arrow heads. A method of attaching a hair replacement device to a wearer's head is disclosed whereby the wearer's own natural hair is pulled through the perforations on the hair attachment flap and secured using adhesive.

Hair loss is a problem which affects many people. While some people affected by hair loss simply accept the resulting change in appearance, others do not and seek devices and methods to replace their lost hair. Over the years, many prior art devices and methods have been devised to help those individuals who wished to maintain the appearance of a full head of hair.
Throughout the worldwide industry of hair replacement and the history thereof, artisans in the practice of non-surgical hair replacement as well as the manufacturers of various types of hair pieces have traditionally strived for better methods of hair attachment. Any method or procedure to be considered would have to address two primary concerns as they relate to the prospective client.
First would be the appearance. The particular method or procedure chosen should enhance the appearance of the user and at least have no negative impact on the aesthetic and realistic qualities of the chosen hairpiece. Second, but no less important is the method of attachment. The method or procedure should improve upon or at least have no negative impact on the level of security and comfort the hair piece attachment method affords.
Traditionally, prior art hair replacement or hair piece attachment procedures have been divided into two categories. There are those referred to as "semi-permanent", such as mechanical clips or double-sided tape. These methods offer the hair replacement wearer the freedom and flexibility to remove the hair piece at will, while providing a reasonable security of attachment in the wind, while swimming, etc.
For other hair replacement clients, only a permanent attachment will do. While there is actually nothing permanent about a permanent attachment, these methods offer the user a higher level of security, as well as a method of attachment that more closely replicates their original hair growth. These methods require a routine maintenance about every four to eight weeks. The most common of the permanent attachment methods are the bond method, the weave method, and what is sometimes referred to as a point attachment.
The bond method, probably the most popular of all the permanent attachment methods, employs any one of a number of medical-grade adhesives and offers the client a reasonable level of security, a low level of detectability, and a reasonable degree of comfort at the time of attachment. Many clients, however, endure a number of drawbacks with this method. Although the mastic used is a medical grade adhesive, prior art methods require the adhesive to be placed directly in contact with the scalp. Many clients suffer an allergic reaction to the mastic, and others complain of a reaction to the bond or the combination of the bond and a tape. This process also requires the user's own hair to be shaved at the point of attachment.
The weave method is actually one of any number of different braiding techniques. While most weave methods offer a relatively high level of security, they vary in diameter and are therefore more difficult to conceal. Also, there is usually a certain level of discomfort that the user must tolerate.
The point attachment method is usually employed by hair replacement specialists who do not weave hair, and are used on a client who can not be bonded. This method, actually can be any number of knotting techniques, and may or may not employ a bonding mastic as well. This method usually offers the least amount of comfort and security and usually has the shortest longevity.
Several prior art patents have disclosed devices and methods to address the deficiencies in the art. For example, U.S. Pat. No. 3,970,092 entitled Method of Attaching a Hairpiece was issued to Nelson on Jul. 20, 1976. This patent disclosed a method of attaching a hairpiece wherein the recipient's natural hair is utilized to "lock" the hairpiece in place. After the hairpiece, which has a base element comprising open-hole netting, has been positioned on the recipient's head, the natural hair underlying the base element is pulled up and through the base. Thereafter, a selected plurality of hair lengths are divided into pairs of groups which are knotted together. Once the knot has been tied, a drop of adhesive is applied to the knot to prevent it from coming loose. This prior art method presents several drawbacks as compared to the invention disclosed herein. First, like most weaving methods, a certain amount of strain is placed on the hair through the knotting, thereby presenting a degree of discomfort to the recipient. Second, this method utilizes an adhesive which may come into contact with the recipient's scalp thereby causing an allergic or non-allergic reaction.
Another prior art method is presented in U.S. Pat. No. 5,033,486 entitled Method for Attaching a Hairpiece to the Scalp which was issued to Finamore, et al. on Jul. 23, 1991. This method comprises removing a strip of natural hair from the recipient along a band below the wearer's natural hair line. Next, an adhesive material is applied along the scalp band in order to affix the hairpiece to the user. As is evident, this prior art method has several disadvantages when compared to the invention disclosed herein. First, it is necessary to remove a band of the wearer's natural hair. Second, as in other bonding methods, the adhesive is applied directly to the wearer's scalp, giving rise to the possibility of reaction or allergy.
Yet a third prior art patent discloses a method of attaching a hairpiece. U.S. Pat. No. 4,296,765 entitled Method and Apparatus for Securing a Hairpiece was issued to Bachtell on Oct. 27, 1981. Here, the hairpiece has a plurality of loops. At each of the plurality of loops, a first adjacent group of natural hair is pulled through the loop and held outwardly extended from the wearer's head under tension. A second adjacent group of natural hair is then pulled through and held under tension so that the two groups of hair cross against each other. A line is then tied about the two groups where they cross and a liquid adhesive is applied to the line. Again, when compared to the invention disclosed herein, the disadvantages of tension on the wearer's natural hair and the application of adhesive are presented.
It is therefore an objective of the present invention to provide a hair replacement device and a method of attaching it to the wearer's head that overcomes the deficiencies of the prior art.
It is further an objective of the present invention to provide a hair replacement device and a method of attaching it to the wearer's head that does not utilize a weaving method.
It is further an objective of the present invention to provide a hair replacement device and a method of attaching it to the wearer's head that does not require an adhesive to make contact with the skin of the wearer's scalp.
It is further an objective of the present invention to provide a hair replacement device and a method of attaching it to the wearer's head that does not require the wearer's natural hair to be shaved prior to installation.
It is further an objective of the present invention to provide a hair replacement device and a method of attaching it to the wearer's head that does not cause stress or tension to the wearer's natural hair.
Other objectives, advantages and novel features, and further scope of applicability of the present invention will be set forth in part in the detailed description to follow, taken in conjunction with the accompanying drawings, and in part will become apparent to those skilled in the art upon examination of the following, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.

Hairpiece and method of attaching hairpiece to user's head


A device for weight training is attached to a weight lifting apparatus, such as a barbell or a selectorized weight machine, to provide a continuously variable resistance force to the lifting bar of the apparatus. As the power demands of the particular exercise decrease and then increase over an exercise cycle due to the musculoskeletal characteristics of the body, this device provides increasing and then decreasing resistance force to dampen out the variations in the power demands over the exercise cycle. A length of latex tubing intended for a specific exercise can be used to provide the variable resistance force. The latex tubing is connected at one end to the weight lifting apparatus and at the other end to an anchor, such as a platform loaded with weights.

1. Technical Field
This invention relates to weight lifting equipment. More particularly, it pertains to a method and apparatus for continuously varying the resistance force exerted by the lifting bar of a weight lifting device.
2. Description of the Prior Art
Generally speaking, there are two types of weight lifting devices in common use today. Each has its own advantages and disadvantages.
One such type is the free-weight barbell. The typical barbell uses a lifting bar with one or more weight plates attached near each end of the bar. The weighted bar is grasped by one or two hands and raised and lowered through an exercise cycle. Some barbells, typically those with a shorter bar, are intended for use primarily for one-handed exercises. These shorter barbells, known as dumbbells, can employ a one-piece construction which combines the lifting bar and weight plates into one piece which prevents varying the fixed weight of the barbell for different exercises for different users. Other barbells, typically those with a longer bar, are intended for use primarily for two-hand exercises. These longer barbells typically employ removable weight plates of various individual weights and means for adding and removing the individual weight plates to and from each end of the bar to vary the fixed weight of the barbell for different exercises and for different users.
The second common type of weight lifting device is the selectorized weight lifting machine which employs a stack of weights channeled for being raised and lowered by a cable and pulleys which connect the stacked weights to a lifting bar. As the lifting bar is raised and lowered through an exercise cycle, a number of the stacked weights, pre-selected by the user for the particular exercise, are raised and lowered. The stacked weights, cable, pulleys and lifting bar are generally interconnected structurally and the path of the lifting bar is typically predefined by the structural connections, unlike the lifting bar of the typical free-weight device which can be moved freely without restriction.
The resistance force of a lifting bar of the more common types of weight lifting devices, against which a user raises and lowers the lifting bar, is fixed and constant through an entire exercise cycle. While benefits of weight lifting with such a fixed and constant resistance force have been well known for many years, the added benefits of weight lifting with a variable resistance force, one which increases as the amount of force required of the body through an exercise cycle decreases and which decreases as the amount of force required of the body through an exercise cycle increases, have become well known more recently.
For weight lifting, power is determined by the amount of force required of a body to move a lifting bar over a prescribed distance in a resultant amount of time. While the time and distance components for determining power remain fairly constant for most exercises, the amount of force required of a body through an exercise cycle will typically vary due to the musculoskeletal features of the body. As a user approaches the midpoint of an exercise cycle, there is typically less difficulty in raising or lowering a lifting bar (i.e. less force required). Conversely, as a user returns to the start and end point of an exercise cycle, there is typically more difficulty (i.e. more force required). Power or strength training to compensate for natural musculoskeletal variations in the amount of required force, with time and distance remaining fixed, involves increasing the resistance force of the lifting bar as the required lifting force decreases in an exercise cycle and decreasing the resistance force of the lifting bar as the required lifting force increases. Power training can permit a user to realize more significant gains in a person's strength and muscle development in a shorter period of time as compared to weight training with a fixed and constant resistance force.
U.S. Pat. No. 5,029,849 discloses an apparatus for varying the resistance force through a defined portion of an exercise cycle. It uses a rather complex series of cords, clips, straps and buckles, in addition to a mechanical type of variable resistance means. The device is intended to apply a variable resistance force through the second step of a defined three-step process of raising and lower a lifting bar. It further discloses means for loosely connecting the apparatus to an end of a lifting bar outside of the weight plates or, presumably, inside the weight plates, assuming the weight plates are removable and the user is inclined to first remove both the weight plates and the means for retaining the weight plates on the lifting bar. This invention further discloses means necessary for physically adjusting the length of the device for physical size differences between individual users.
It is an object of the present invention to provide a variable resistance force to a lifting bar of a weight lifting device throughout a complete exercise cycle. It is a further object of the present invention to provide an apparatus which permits a safe, quick, and easy connection to and removal from the lifting bar of such a device without the need to remove any weight plates. It is a further object of the present invention to provide a device which minimizes the need to adjust the length of the apparatus for physical size differences between individual users. It is yet a further object of the present invention to provide means for allowing a particular user to easily increase the amount of variable resistance force to use for a particular exercise.

Apparatus for continuously varying the resistance force of a weight training device


A drying device includes an air/air heat exchanger and an air/refrigerant heat exchanger. The air refrigerant heat exchanger includes a phase change material.

Air dryers are generally utilized to remove water vapor typically from compressed air or gas. Where refrigerant-type air dryers are employed, a refrigerant system is used to lower the temperature of the air or gas being dried to a temperature at or below the condensation temperature of water therein. At such temperatures, water vapor in the undried air condenses on a surface within a condenser where it can be collected and purged from the system.
In order to sufficiently lower the temperature of the undried air or gas, many refrigerant systems comprise a heat exchanger where heat is drawn from the air or gas being dried to a refrigerant. Typically, heat from undried air is coupled to the evaporation of a colder refrigerant in an evaporator. In this case, as the liquid refrigerant is vaporized, it removes heat from the undried air or gas and cools the air in the process. When the air or gas reaches a temperature at or below the condensation temperature of water therein, the net result is that the water vapor therein begins to condense (or separate) from the air or gas and is collected in a condenser or separator.
In order to recycle the refrigerant in the system, a compressor and a chiller unit are often installed—the compressor compresses the gaseous refrigerant that has been vaporized in the chiller, and the condenser condenses the gaseous refrigerant into a high pressure liquid. The refrigerant, is then ready for another cycle of vaporization.
A common problem with refrigeration-type dryers is determining how to suspend cooling (i.e., "de-energize" the system) during times of no load or low load conditions. For example, the demand for refrigeration is low or non-existent when little to no air is flowing through the refrigerator dryer or when the incoming air is already cool. Typically, it is desirable to reduce or discontinue cooling during such periods to avoid ice formation in the refrigerant system that could affect operation of the refrigeration air dryer. Ice can plug the system so that it does not continue drying the air, or it can plug the air passages stopping the flow of compressed air.
One way to prevent excessive cooling and the resulting problem, is to use a cycling-type refrigeration dryer. In a cycling refrigeration-type dryer system, a thermostatic temperature device causes de-energizing of a refrigerant compressor when the undried air has been cooled to a predetermined temperature. This can also be accomplished by measuring the evaporator pressure. The same device can then cause the compressor to be re-energized when the temperature in the evaporator elevates to a predetermined temperature, indicating further cooling is required to remove moisture from the incoming air. Thus, it has been found that between adequate load and low load conditions, a refrigeration compressor may cycle on and off about thirty to forty times per hour.
The number of cycles per hour is significant because frequent cycling adds costs associated with wear and tear on the compressor, control systems, and valves. As a result, the life without maintenance of the refrigeration system is drastically reduced. Accordingly, it would be desirable to provide a refrigerant air dryer system and method that extends the life of its refrigeration system.
Moreover, the greater the number of times a refrigeration system cycles, the greater the amount of energy that is consumed. Lower energy consumption has both cost and environmental benefits. Accordingly it would also be desirable to provide a refrigeration dryer system and method that reduces the amount of energy consumed.

Refrigeration-type dryer apparatus and method


A method of gray component replacement receives a current pixel color value. A highlight likelihood and color neutrality is determined for the current pixel color value. An output pixel color value depending upon the color neutrality and the highlight likelihood is generated. The input pixel color value is obtained from an image acquisition system and the output color pixel value is used by an output engine to render the pixel.

In digital printing systems, a picture element (pixel) may be defined as a space on a page into which dots of ink, dye or toner are placed. The placing and number of the dots determines how a human eye integrates the dots and picture elements into an image. Colors of pixels, for example, are generally controlled by the number of dots of different colors of ink within the space. A pixel having a high concentration of yellow dots will appear mostly yellow. The yellow can be altered to appear greener or more orange by the addition of dots of the other colors.
Generally, color imaging processes use subtractive coloring to achieve color images. In digital display systems, the substrate upon which an image is displayed, the screen, is generally considered to be black and colors are added together to form color images. In digital printing, the substrate is generally white, so colors are added together to subtract color from white. The subtractive colors are cyan, magenta and yellow (CMY).
In dye-based color printing systems, the dyes have high purity and intensity and the color black may be recreated on the paper by mixing the three colors together. In ink and toner-based systems, however, that is not usually the case. The mix of CMY generally results in an intermediate brownish color, not black. Therefore, black is added to the available inks and toners, and is represented by the color K.
When an image is produced using CMYK, the addition of black requires that the other color amounts be altered to account for the addition. This process is generally referred to as gray component replacement (GCR) or under color removal (UCR). Most GCR systems rely upon a series of equations that are applied to the current CMYK values of a given pixel. These equations generally only use the minimum value of the CMY values for the current pixel. This may be thought of as performing a one-dimensional GCR process.
For print mode, this one-dimensional method of GCR seems sufficient for the most applications. However, for such applications as the copy mode of multi-function device, where the electronic scan image is a mix of text, pictorial and graphic contents, the one-dimensional GCR process may result in objectionable artifacts in the final output hardcopy, such as graininess in highlight areas, color fringing, texture contouring, edge blurring, and reducing of color in dark areas.

Two-dimensional gray component replacement


A tunable optical dispersion compensator (TODC) having a silica arrayed-waveguide grating (AWG) directly coupled at its input to a Mach-Zehnder interferometer device and at its output to a polymer thermo-optic lens.

In long-distance transmission of optical signals, the accumulation of chromatic dispersion in optical fibers presents serious problems. These problems intensify with an increase in bit rate and the distance traveled by the optical signals. Efforts to date that compensate for dispersion have primarily involved the use of dispersion compensating optical fibers (DCF).
Dispersion compensating efforts that employ DCF—while well-proven—are not particularly amenable to integration in existing network elements. This is due—in part—because DCF is employed as a large spool of fiber which occupies significant space in a network office and is not adjustable. In addition, service providers that utilize DCF in their networks must accurately characterize their fiber, deploy more expensive optical amplifiers and accept additional latency added to links employing the DCF [˜20% additional latency for a fully compensated standard-single-mode fiber (SSMF) link]. Finally, DCF cannot satisfy all of the dispersion compensation requirements of many 40-Gb/s links, consequently a tunable optical dispersion compensator (TODC) having a small tuning range is often required in addition to the DCF.
A TODC employing an arrayed waveguide grating (AWG) and thermo-optic lens was described in U.S. Pat. No. 7,006,730 directed to a "Multichannel Integrated Tunable Thermo-Optic Lens and Dispersion Compensator the entire contents of which are hereby incorporated by reference. The TODC described therein appeared to be an attractive alternative/supplement to DCF.

Tunable optical dispersion compensating apparatus


A unit for feeding products (3) to a blistering machine (M) includes a delivery group (2, 2a, S) for selectively distributing products (3) to a station (SR), where the products (3) are introduced into respective blisters (40) of a blister band (4), moving in a forward direction (W) inside the blistering machine (M). The filling station (SR) is defined by a conveyor (10) consisting of a belt (11) provided with seas (110). Each seat (110) receives a relative product (3) distributed by the delivery group (2, 2a, S) and releases the products (3) into a respective blister (4). The conveyor (10) include at least one endless belt (11), moving in step relation with the blister band (4) wound around respective pulling wheels (13, 14), with an upper portion of the belt (11) defined by an upper run (11a) extending under the delivery group (2, 2a, S) in a direction parallel to the forward direction (W), defined by a lower run (11b) extending, along at least a section (O) parallel to the forward direction (W), substantially very close to and above the blister band (4) and facing the blister band (4).

Currently, in an automatic blistering machine, a continuous band of heat-weldable material, or of aluminium, is driven to move forward through different working stations in the following order: a forming station, where receptacles, or blisters, are made in the band, a station, where the products are fed and the blisters are filled with the products, a station, where the upper surface of the band is sealed, and a station, where the pieces of the band containing a predetermined number or blisters, and consequently of products, are cut, each of these pieces forming a blister pack.
A unit is situated at the above feeding and filling station for feeding products and introducing them into the blisters. The above unit assures a correct filling of all the blisters, as well as the integrity of the products, so as to reduce jams and wastes of products, all this while maintaining the required high production speed.
Among different proposed solutions, one particularly advantageous is described in the International Patent Application PCT Num. WO 01/42088 of the same Applicant.
According to this solution, a unit for feeding products to a blister band situated below includes basically selection means which form a plurality of longitudinal channels, arranged in such a way as to define an oscillating grid and aimed at receiving products coming from the hopper situated above.
The selecting means are connected to suitable oscillating means, which generate a relative oscillating movement, crosswise and/or longitudinally, between the selecting means and the blister band opposite thereto, so as to facilitate stable introduction of the products present in the longitudinal channels, falling down into the corresponding blisters formed in the band.
A system of this kind requires overfeeding of products; therefore, in a fixed interval of time, the hopper must feed the selecting means with a number of products exceeding the number of blisters facing the grid in this interval of time.
Then, downstream of the selecting means, the exceeding products, which are not yet introduced into the blisters, are usually conveyed, by suitable collecting means, to the feeding hopper and then re-cycled.
The above described unit is functionally efficient, in particular as regards filling of blisters, which are usually sized as the products they must contain, i.e. the dimensions of the blister are slightly bigger than the dimensions of the product; the difference between the dimensions of the blister and the product facilitates the product introduction, but prevents more products from being introduced into the same blister.
In some cases, an product must be introduced in a blister much bigger than it is necessary in normal situation, i.e. in order not to modify the dies in the blister forming station: in this situation, known devices of the above described type do not manage to prevent two or more products, instead of only one, from entering each blister.
In other cases, blisters filling operation must be performed with bigger care with respect to the unit described in the above mentioned International Patent Application PCT Num. WO 01/42088, or other known devices, in order to protect the products integrity.
This necessity is more frequent with products like tablets, which are rougher and more friable than sugarcoated pills and less sliding with respect thereto, or in situations in which aluminium band is used, less resistant to denting than the band of plastic material.

Unit for feeding products to a blistering machine

I.M.A. Industria Macchine Automatiche S.p.A.


A seismic acoustic signal source includes a hull that has a wetted surface in contact with a body of water. When underway, the draft of the hull is substantially zero. An acoustic signal generator is provided with a linear actuator that is resiliently mounted in the hull. The linear actuator is acoustically coupled to the hull bottom such that when the signal generator is activated, the hull radiates an acoustic wavefield into the water.

1 . Field of the Invention
A marine seismic acoustic signal generator is installed in a small, substantially zero-draft marine support vehicle that is usually towed behind a service ship in a body of water. In operation, the entire vehicle becomes an acoustic wavefield generator.
2 . Discussion of Related Art
As is well known to geophysicists, a sound source, at or near the surface of the earth, is caused periodically to inject an acoustic wavefield into the earth at each of a plurality of regularly-spaced survey stations. The wavefield radiates in all directions to insonify the subsurface earth formations whence it is reflected back to the surface to be received by seismic sensors (receivers). The seismic sensors are located at designated stations at or near the surface of the earth. The seismic sensors convert the mechanical earth motions (or water-pressure variations in a marine environment), due to the reflected wavefield, to electrical signals. The resulting electrical signals are transmitted over a signal-transmission link of any desired type, to instrumentation, usually digital, where the seismic data signals are archivally stored for later processing. The travel-time lapse between the emission of a wavefield by a source and the reception of the resulting sequence of reflected wavefields by a receiver, is a measure of the depths of the earth formations from which the respective wavefields were reflected.
The seismic survey stations of a 3-D survey are preferably distributed in a regular grid over an area of interest with inter-station spacings on the order of 25 meters. The processed seismic data associated with a single receiver location are customarily presented as a one-dimensional time scale recording displaying rock layer reflection amplitudes as a function of two-way wavefield travel time. A plurality of seismic traces from a plurality of receivers distributed sequentially along a line of survey may be formatted side-by-side to form a model of a cross section of the earth (two-dimensional tomography). Seismic sections from a plurality of intersecting lines of survey distributed over an area of interest, provide three-dimensional tomography.
At sea, in deep water, the sensors are mounted in one or more streamer cables and towed through the water by a cable ship. In relatively shallow water, the sensors and their connecting cables are laid on the sea floor from a service boat. Alternatively, in shallow water and the transition zone (the surf), the sensors may be associated with instrumented buoys. All of these techniques are well known to the art and need not be dwelt upon further.
In marine operation, a service (shooting) ship tows an acoustic source such as an array of air guns, a chirp signal generator or other device through the water over the region to be surveyed. As it visits each survey station, the source is triggered to generate a desired wavefield. One such device is disclosed in U.S. patent application Ser. No. 3,384,868, issued May 21, 1968 to G. Brown et al., which is incorporated herein by reference. This is an apparatus for the generation of seismic energy waves within a water medium which consists of a rigid frame member and suspension attachments, the frame member movably securing a piston plate between upper and lower sealed bellows which are alternately pressurized by reciprocal oil flow to vibrate the piston plate relative to the frame member, the apparatus also including the employ of additional bellows which is sealed between the piston plate and frame member to receive varying air pressure to thereby maintain static-pressure balance.
A somewhat similar device is taught by U.S. Pat. No. 3,329,930, issued Jul. 4, 1967 to Jimmy R. Cole et al. This source is a submerged hydraulic vibrator having an inverted bell-shaped body member closed on the bottom by a flexible plate. An hydraulic servo valve, mounted in a cylindrical housing secured to the body member, vibrates a piston that is coupled to the flexible bottom plate. The assembly is designed to be towed through the water, imparting vibratory signals thereto at selected survey stations.
The drag produced by the towed sources necessarily slows down the shooting ship, reducing the production rate of stations occupied per unit time and is therefore costly. It would appear to be useful to incorporate the acoustic source into the structure of the shooting ship itself in a streamlined configuration.
One such system was disclosed in U.S. Pat. No. 3,401,660, issued Sep. 17, 1968 to Booth B. Strange et al. for a Seismic Ship. Here, wells on the order of eight feet in diameter extend from the working deck through the ship's bottom, opening into the water. By means of a crane, a suitable sound source is lowered into the well flush with the hull, but immersed in the water. Either a chirp-signal generator or an impulse-type source was used.
The disadvantage of that particular arrangement was the need for totally-enclosed, sealed sound sources and the wells, open to the sea penetrating the ship's hull. The devices were unwieldy, had a tendency to protrude beneath the hull and were difficult to service during active operations by reason of their total immersion. Furthermore, each time the source was activated, the ship was severely shaken which threatened its structural integrity.
A number of marine sources are known which rely upon a pair of opposing pistons mounted in a sleeve that are initially in intimate contact. The pistons are, by hydraulic or electro-hydraulic means, caused to abruptly expand outwardly from each other, against a volume of water, to radiate a wavefield in the water. The wavefield may be periodic, impulsive or implosive. Typical of such sources is described in U.S. Pat. No. 4,153,135, issued May 8, 1979 to John Bouyoucos for an APPARATUS FOR THE GENERATION OF ACOUSTIC SIGNALS IN MARINE ENVIRONMENTS. Several similar types of marine sources are illustrated in another Bouyoucos U.S. Pat. No. 4,207,962, issued Jun. 17, 1980.
Underwater acoustic sources towed through the water experience hydrodynamic drag which slows progress and increases operational expenses. Submerged mechanical acoustic sources also require watertight integrity of the components, both mechanical and electrical, which increases production and maintenance expenses. Furthermore, most submerged vibratory acoustic sources require that the pressure of the interior of the device be equalized with the ambient water pressure in order for the device to operate properly. A significant problem with underwater towed marine sources is the first ghost reflection from the water surface, which produces notches in the farfield power spectrum.