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排序方式: 共有1347条查询结果,搜索用时 62 毫秒
1.
Polarity Effect and Electromagnetic Radiation of Partial Discharge Accompanying Growth of Electrical Tree
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Tatsuya Mutakamihigashi Yoshito Kuroishi Hideki Ueno 《Electrical Engineering in Japan》2015,192(3):19-26
We have investigated the characteristics of radiated electromagnetic (EM) waves from positive and negative partial discharges (PD) in epoxy resin and cross‐linked polyethylene. We found that there is a correlation among the EM level from PD, the positive PD current, and electrical trees. Therefore, the growth of an electrical tree produces a lot of positive PD. We have also investigated the characteristics of the frequency region of EM waves from PD in air, insulating oil, and liquid epoxy in addition to the above insulators. EM waves were detected in the frequency region of 40 MHz to 300 MHz from positive and negative PD in epoxy resin and cross‐linked polyethylene. EM waves were also detected in the frequency region of 40 MHz to 150 MHz from positive and negative PD in air. In the case of insulating oil and liquid epoxy, EM waves were detected in the frequency regions of 40 MHz to 150 MHz from positive PD, and 40 MHz to 250 MHz from negative PD. The frequency region differed depending on the material and the discharge polarity. Our investigation indicates that the cause is differences in electric field strength at the time of PD occurrence. 相似文献
2.
Eicosapentaenoic acid (EPA) production by an oleaginous fungus Mortierella alpina expressing heterologous the Δ17‐desaturase gene under ordinary temperature
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3.
Tatsuya Hanaoka Hisashi Ishitani Ryuji Matsuhashi Yoshikuni Yoshida 《Applied Energy》2002,72(3-4):705-721
The objective of this study is to evaluate the potential for recovering fluorocarbons as measures for the abatement of global warming. In this study, we focused on the three different kinds of fluorocarbons: CFCs, HCFCs and HFCs, and targeted refrigerant use because of the availability of relevant data. We first estimated future fluorocarbon emissions from the targeted appliances; we next compared those emissions in the units of CO2 equivalent to the level of CO2 emissions in 1990 from a quantitative point of view. As the result of this study, it was found that fluorocarbon emissions in 1999 and 2010 would be equal to approximately 7 and 3% of the level of CO2 emissions in 1990 respectively. Moreover, if we implement a 100% recovery rate in every recovery route, we can reduce a large amount of emissions which correspond to approximately 2–5% of the level of CO2 emissions in 1990, even if we take into account the energy-related CO2 emissions by the transportation and decomposition of fluorocarbons. 相似文献
4.
Wakejima A. Matsunaga K. Okamoto Y. Ando Y. Nakayama T. Miyamoto H. 《Electronics letters》2005,41(25):1371-1372
A single-ended amplifier using small packaged GaN-FETs exhibits a record 2.14 GHz W-CDMA output power. The amplifier, composed of paralleled 48 mm gate periphery FET die, delivers a peak saturated output power of 371 W with a linear gain of 11.2 dB at a drain voltage of 45 V under 2.14 GHz 3GPP W-CDMA signal input. The output power density (output power/package size) of 1.1 W/mm/sup 2/ is twice as high as that of the existing over 300 W GaAs-FET amplifiers. A low 5 MHz offset ACLR of -36 dBc with a drain efficiency of 24% is also obtained at 8 dB power back off from the saturated output power. 相似文献
5.
Drew Michael R.; Yang Cynthia; Ohyama Tatsuya; Balsam Peter D. 《Canadian Metallurgical Quarterly》2004,30(3):163
Three experiments investigated the effects of varying the conditioned stimulus (CS) duration between training and extinction. Ring doves (Streptopelia risoria) were autoshaped on a fixed CS-unconditioned stimulus (US) interval and extinguished with CS presentations that were longer, shorter, or the same as the training duration. During a subsequent test session, the training CS duration was reintroduced. Results suggest that the cessation of responding during an extinction session is controlled by generalization of excitation between the training and extinction CSs and by the number of nonreinforced CS presentations. Transfer of extinction to the training CS is controlled by the similarity between the extinction and training CSs. Extinction learning is temporally specific. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
6.
Yuji Oie Tatsuya Suda Masayuki Murata Hideo Miyahara 《International Journal of Satellite Communications and Networking》1991,9(5):285-303
One of the most promising approaches for high speed networks for integrated service applications is fast packet switching, or ATM (asynchronous transfer mode). ATM can be characterized by very high speed transmission links and simple, hard-wired protocols within a network. To match the transmission speed of the network links, and to minimize the overhead due to the processing of network protocols, the switching of cells is done in hardware switching fabrics in ATM networks. A number of designs have been proposed for implementing ATM switches. Although many differences exist among the proposals, the vast majority of them are based on self-routeing multistage interconnection networks. This is because of the desirable features of multi-stage interconnection networks such as self-routeing capability and suitability for VLSI implementation. Existing ATM switch architectures can be classified into two major classes: blocking switches, where blockings of cells may occur within a switch when more than one cell contends for the same internal link, and non-blocking switches, where no internal blocking occurs. A large number of techniques have also been proposed to improve the performance of blocking and non-blocking switches. In this paper, we present an extensive survey of the existing proposals for ATM switch architectures, focusing on their performance issues. 相似文献
7.
Immunoassay method for the determination of immunoglobulin G using bacterial magnetic particles. 总被引:7,自引:0,他引:7
We have developed a novel immunoassay method using bacterial magnetic particles for the determination of immunoglobulin G (IgG). Fluorescein isothiocyanate (FITC) conjugated anti IgG-bacterial magnetic particles were prepared. The fluorescence quenching caused by agglutination of FITC-anti IgG antibody-bacterial magnetic particle conjugates was measured by using a fluorescence spectrophotometer. The aggregates based on specific immunoreaction were separated by a gelatin solution. The aggregation of bacterial magnetic particle conjugates was enhanced by application of a magnetic field. The relative fluorescence intensity correlated linearly with a concentration of IgG in the range 0.5-100 ng/mL. 相似文献
8.
K Matsunaga M Oofukuji S Syukuwa M Osabe Y Takeno H Isomoto Y Mizuta S Kohno 《Canadian Metallurgical Quarterly》1997,24(15):2281-2284
The patient was a 83-year-old female with 2' T2-type gastric cancer associated with positive H. pylori in the lesser curvature of the stomach. The patient was treated with oral UFT-E alone in a daily dose of 400 mg. The tumor exhibited an O' IIa + IIc-like appearance 4 weeks after the start of administration and became scarred 8 weeks later, revealing marked tumor reduction in a short period of time. At 8 weeks, biopsy showed marked polymorphonuclear cells infiltration of gastric mucosa with no evidence of malignancy. In an attempt to eradicate H. pylori, 30 mg of lansoprazole, 400 mg of clarithromycin, and 2.0 g of ecabet-Na (3.0 g of Gastrom) were administered for 2 weeks. H. pylori was found to have been successfully eradicated, and the inflammatory lesions were no longer visible histologically. UFT-E was highly effective in this patient, and the eradication of H. pylori may contribute to the prevention of cancer recurrence. 相似文献
9.
T Saita M Katano H Matsunaga H Yamamoto H Fujito M Mori 《Canadian Metallurgical Quarterly》1993,41(3):549-552
Antitumor polyacetylenic alcohol, panaxynol, was isolated and purified from a powder of the root of Panax ginseng C.A. Meyer. Panaxynol inhibited the growth of various kinds of cultured tumor cell lines in a dose-dependent manner. In this paper we demonstrated the first specific antibody production against panaxynol. Anti-panaxynol antibody was elicited in rabbits by immunization with panaxynol hemisuccinate-bovine serum albumin conjugate (panaxynol hemisuccinate-BSA conjugate). An enzyme immunoassay (EIA) for the determination of panaxynol was established using a double-antibody technique. The EIA was highly specific against panaxynol although the antibody showed a minimal cross-reactivity with other types of polyacetylenic alcohol, i.e. panaxydol (12.0%) and panaxytriol (0.77%). Panaxynol at a concentration as low as 6.4 ng/ml can be detected. Using this assay we reconfirmed the rapid consumption of panaxynol by target tumor cells in an in vitro-culture system. The anti-panaxynol antibody may be a valuable tool for studies of the biological properties of polyacetylenic compounds. 相似文献
10.
Color‐vision deficiency is a relatively common genetic condition, which often leads to the obstruction of necessary information in colored images. It is important to minimize such inconvenient effects in communication using colored images from a universal design perspective. The universal design principle stipulates that all environments and products should be usable by all people, regardless of age, physical attributes, and ability. This article proposes a method to detect color combinations in a given image that would confuse color dichromats, and suggests a way in which to modify them to make the image easily distinguishable for both normal and dichromatic observers. Confusing color combinations were detected based on a color‐difference calculation using simulations of how the color would appear to dichromats. The confusing colors were then modified based on the minimization of an evaluation function, which was defined as the sum of the degree of confusion and the degree of color change from the original image. Several colored images obtained by the proposed method were compared with the originals by red–green dichromatic observers who judged them to be clearer, thereby confirming that the proposed method was effective for color rendering for universal design. © 2008 Wiley Periodicals, Inc. Col Res Appl, 33, 203–211, 2008 相似文献