電気学会論文誌A(基礎・材料・共通部門誌)
Online ISSN : 1347-5533
Print ISSN : 0385-4205
ISSN-L : 0385-4205
132 巻, 8 号
選択された号の論文の21件中1~21を表示しています
解説
  • 鳥居 祥二
    2012 年 132 巻 8 号 p. 603-608
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    The CALET (CALrimetric Electron Telescope) is an Astrophysics mission for the International Space Station (ISS) that will search for signatures of Dark Mater and provide the highest energy direct measurements of the cosmic ray electron spectrum in order to observe discrete sources of high energy particle acceleration in our local region of the Galaxy. CALET will address many of the outstanding questions including; (1) the nature of the sources of high energy particles and photons, through the high energy spectrum, (2) the details of particle transportation in the Galaxy, and (3) signatures of dark matter, in either the high energy electrons or gamma ray spectrum. It will also be capable of monitoring gamma ray transients and solar modulation. The unique feature of CALET is its thick, fully active calorimeter that allows well into the TeV energy region with excellent energy resolution, coupled with a fine imaging upper calorimeter to accurately identify the starting point of electromagnetic showers. It is in the TeV region that we anticipate being able to observe, for first time, an unambiguous signature of energetic particles (electrons) accelerated in specific sources in our local region of the Galaxy and then propagating to Earth.
論文
  • Makoto Suzuki, Chihiro Mitsuda, Kenichi Kikuchi, Toshiyuki Nishibori, ...
    2012 年 132 巻 8 号 p. 609-615
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    The Superconducting Submillimeter-Wave Limb-Emission Sounder (SMILES) has made observations in the Earth's atmosphere from the Japanese Experiment Module (JEM) since October of 2009 to April of 2010, with the aid of 4-K mechanical cooler and super-conductive mixer for the submillimeter limb-emission sounding. The outline of SMILES instrument and its operation on board, as well as sensitivity of SMILES to the chlorine monoxide, ClO, are described. Theoretical ClO detection capability of SMILES at upper stratosphere (25-45 km) is verified by using observed data, and limitations of ClO detection below 25 km and above 45 km are discussed.
  • 武田 明, 高田 和之, 長尾 尋智, 王 建青, 藤原 修
    2012 年 132 巻 8 号 p. 616-622
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    We previously measured for healthy subjects and patients who require hemodialysis the complex relative permittivity (εr´-r´´) of whole blood, and found that εr´-axis intercept εrt´ of straight line approximation to the Cole-Cole plots at frequencies from 200 MHz to 1GHz is significantly different with a level of less than 1% among its averaged values for healthy subjects and patients before and after dialysis, though any correlations between εrt´ and blood urea nitrogen (BUN) and creatinine being used as main indices for hemodialysis evaluation have not so far been clarified.
    In this study, to make correlation analyses between the intercept εrt´ and blood biochemical components for nine patients before and after hemodialysis, we measured six kinds of their blood components including BUN and creatinine, and calculated their Pearson product-moment correlation coefficients for εrt´ along with significant probability P based on a t-test. It should be noted that P is a reference probability to determine whether or not a null hypothesis can be rejected, and that the P value of 0.05 is commonly used as a significance level for statistical test. As a result, we found that a strong correlation with P < 0.05 is observed between εrt´ and albumin, while there are not always significant correlations with P > 0.05 between εrt´ and other blood components including BUN and creatinine. Although albumin is not used as an index for hemodialysis efficiency, it can reflect water amount in blood vessels and liver operation. This finding implies that εrt´ could be used as an index for evaluating blood viscosity and liver function.
  • 松田 昭博, 稲嶺 盛克, 寺本 徳郎, 水谷 嘉伸, 五島 久司, 新開 裕行
    2012 年 132 巻 8 号 p. 623-629
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    In this paper, a numerical analysis of thermo-mechanical viscoelastic material was investigated to predict the compression set of EP-rubber O-rings for substation facilities. Relaxation times for viscous characteristics of this model were calculated by the Arrhenius equation and temperature of rubber. Furthermore, biaxial loading tests by loading test machine and the stress-relaxation tests in the thermal chamber were conducted to evaluate the mechanical and thermal characteristics and effect of temperature on the stress relaxation to confirm the applicability of the simulation code. From the simulated results, the developed code shows enough accuracy to predict the stress reduction of natural rubber parts under the long-term compression.
  • 脇本 亨, 高橋 芳光, 木村 統公, 鳴海 礼斗史, 早川 直樹
    2012 年 132 巻 8 号 p. 630-637
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    This paper presents a plain method to calculate the voltage waveform at the motor input terminals from the inverter output terminal voltage and also a method to reduce the voltage. The voltage waveform at the motor input terminals is obtained by the frequency domain calculation using the transfer function of the cable and the frequency characteristics of the voltage waveform at the inverter output terminals. The analysis using this method clarifies the mechanism of the rise of the maximum voltage at the motor input terminals, that is, the ringing at the motor input terminals, which occurs at specific frequencies at which transfer gain increases, causes the rise of the maximum voltage. Therefore, to decrease the maximum voltage at the motor input terminals, it is effective to shorten the cable length or cancel the ringing voltage by pre-switching.
  • 石塚 一男, 蓮沼 輝男, 渡邊 慎也, 海渕 住男, 岡野 好伸
    2012 年 132 巻 8 号 p. 638-648
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    In this paper, a optimized shape of EM wave absorber is calculated using a optimization method called Downhill Simplex Method. As a result of optimization, the necessity for periodically changing an equivalent permittivity in the direction of the thickness of EM-absorber is shown. To confirm this result, the absorber which has a periodic permittivity distribution is made and the reflection coefficient is measured. In the measurement results, the optimization shape absorber shows multi-resonance. Additionally, that absorption is 5dB to 15dB better than the conventional pyramidal absorber's performance in the 60MHz to 300MHz frequency range.
  • Michal Piotr Kwiatkowski, Saburoh Satoh, Chobei Yamabe, Satoshi Ihara, ...
    2012 年 132 巻 8 号 p. 649-655
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    The purpose of this study was to investigate the electrical energy for the environmental applications using AOPs (advanced oxidation processes) combined with ozonation and sonication to remove the FOG (fats, oils and greases) from wastewater of the sewage system. This study focused on FOG removal from a grease trap using the hybrid AOPs. Fatty acids (linoleic, oleic, stearic and palmitic acids) were used as representative standards of FOG. The studies were conducted experimentally in a glass reactor under various operational conditions. The oxidation efficiency using the combination of the ozonation and sonication was determined by the KI dosimetry method and the calorimetry method. Fatty acids concentration were measured by GC/MS. The local reaction field of the high temperature and high pressure, so-called hot spot, was generated by the quasi-adiabatic collapse of bubbles produced in the water under sonication, which is called cavitation phenomenon. Mixing the ozone bubbles into the water under acoustic cavitation, the formation of OH radicals increased. The mechanical effect of acoustic cavitation such as microstreaming and shock waves have an influence on the probability of reactions of ozone and radicals with fatty acids.
  • 猪原 哲, 廣幡 大樹, 小湊 佑一, 山部 長兵衛, 池 英昭, 吐合 一徳, 平林 和也, 玉川 雅章
    2012 年 132 巻 8 号 p. 656-663
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    New method of water treatment for wastewater using discharge in water cavitation field, in which numerous micro bubbles were generated by high-speed water flow, was proposed in this paper. Indigo carmine solution, which is a type of dye, with a concentration of 9mg/Liter was used as a specimen for demonstration of water treatment. The total volume of solution and average speed of solution in the cavitation field was 20 Liter and about 7.4 m/s, respectively. A reduction ratio of absorbance of 96% was obtained in 50 min of treatment time at an electrode distance of 2 mm and a discharge power of 16 W. Also it was found that the efficiency of decolorization was improved by changing the electrode location.
  • 布川 史章, 六角 虎太郎, 鈴木 進, 矢沢 勇樹, 伊藤 晴雄
    2012 年 132 巻 8 号 p. 664-669
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    Pulsed discharge in bubbles generated by pulsed power source is applied to water treatment containing persistent substances, which are mainly organic substances in water and have recently resulted in environmental damage. Humate, the target in this study, is one of the persistent substances.
    A Blumlein type pulse forming network (B-PFN) is provided in the work. The reactor is constructed by a cylinder equipped with a pair of electrode, which are an injection needle and a spiral electrode. The gas used for bubbles are helium, oxygen and nitrogen. In this study, the absorbance from 280 to 600 nm in the wavelength and the total carbon concentration of the humate solution is measured by a spectrophotometer and a total organic carbon analyzer. From the results, the decrease of the absorbance in humate solution is observed and elucidated certain variation of chemical bonding condition in the humate solution. The decreasing rate of the humate solution by pulsed discharge in nitrogen bubble is larger than the pulsed discharge in oxygen and helium bubbles. The organic carbon concentration has decreased by the pulsed discharge in oxygen and nitrogen bubble.
  • 酒井 英男, 永田 翔一, 升方 勝己
    2012 年 132 巻 8 号 p. 670-675
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    In our previous studies, we showed that the remanent magnetization of the material could analyze the lightning current at the ground. In this study, using IG (Impulse Generator) current as a model of lightning, we investigated the underground propagation of the IG current from the remanent magnetization. For this purpose, we dug a square hole with a side length of 80 cm and depth of 13 cm, and placed in it the magnetic samples prepared using sea sand. After injecting an IG current of 530 A underground, the magnetization of these samples was measured.
    The directional distribution of magnetization successfully analyzed the circular magnetic field induced by the IG current and its transit point. Then, the underground path of IG current was determined to a depth of 12 cm. The path of current inclined by approximately 9° from the vertical direction, which may be attributed to the earth conductor being located east of the experimental area. As the relational expression between the intensity of magnetization and the distance from the IG current, an inverse square relation was applied besides the area near the transit point of the current.
    From the results in this study, we conclude that the method using remanent magnetization is useful to elucidate the polarity, intensity and path of both the IG and lightning current underground. Further, the method of using remanent magnetization as a record of lightning current may contribute to the development of an effective earth conductor for limiting damage caused by lightning.
  • 中野 光昭
    2012 年 132 巻 8 号 p. 676-683
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    I have studied the relationship between electrical conduction and the EHD motion induced in mineral oil, between metal electrodes when their polarities are reversed. This paper describes the results of a three-dimensional numerical calculation on the relationship between electrical conduction and EHD motion. The equations used in the calculation are Euler's equation of continuity, the Navier-Stokes equation, Poisson's equation, and the equation of charge continuity. Primarily, the time dependence of the current waveform, the distribution of charge density, and flow velocity are calculated. The main results are as follows: (1) The EHD motion increases the current, inducing a peak in the current waveform. (2) The coulomb force in the vicinity of the electrode/oil interfaces after the reversal of the electrode polarity satisfies the condition for inducing EHD motion. (3) The distribution of space charge density and the flow velocity between electrodes are visualized using a three-dimensional diagram of contour surfaces and the three-dimensional vector diagram.
  • 中野 光昭
    2012 年 132 巻 8 号 p. 684-691
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    I have studied the relationship between electrical conduction and the EHD motion induced in mineral oil, between metal electrodes when their polarities are reversed. This paper describes the results of the three-dimensional numerical calculations of electrical conduction and the EHD motion induced in mineral oil by the reversal of electrode polarities at the time of peak current. The calculation employs Euler's equation, the Navier-Stokes equation, Poisson's equation, and the equation of charge continuity. The main results are as follows: (1) The calculation results of the current waveform are in agreement with the experimental results, with the exception of the time range that has large effects due to charging and absorption currents. (2) The current waveform is related to the time dependence of the current induced by the flow. (3) The distribution of space charge density and flow velocity between electrodes are visualized by the three-dimensional diagram of contour surfaces and the three-dimensional vector diagram.
  • 菊池 英行, 岩崎 富生, 花輪 秀仁, 本田 祐樹
    2012 年 132 巻 8 号 p. 692-697
    発行日: 2012/08/01
    公開日: 2012/08/01
    ジャーナル フリー
    We studied the particle dispersion mechanism of polyamide-imide/silica nano-composite material by using molecular-dynamics simulation technique based on Newtonian dynamics and quantum mechanics. In simulations, adhesive fracture energies at the interfaces between silica and solvents were calculated, and Brownian motions of silica particles were simulated to clarify dispersion properties. The simulation results showed that the colloidal state of silica was maintained by covering the silica surface with a new low hygroscopicity solvent and that the chemical structure of polymer contributed to the dispersion of silica. It is found that the results obtained from molecular dynamics agree well with those obtained by experiments, and that molecular-dynamics simulation technique will become very useful for the development of nano-composite materials in the future.
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