Journal of Advanced Science
Online ISSN : 1881-3917
Print ISSN : 0915-5651
ISSN-L : 0915-5651
19 巻 , 3+4 号
選択された号の論文の9件中1~9を表示しています
Paper
  • -ドゥビュッシーとラヴェルのピアノ曲の比較-
    Tomoaki NIIZUMA, Atsuko TOBA, Yukiko YAJIMA, Keiichi HISADA, Shigeki O ...
    2007 年 19 巻 3+4 号 p. 41-46
    発行日: 2007年
    公開日: 2008/03/18
    ジャーナル フリー
    In order to apply the physical 1/fβ fluctuation analysis to the musicological style analysis, we measured the adjusted β-values of the logarithmic plots of the power spectrum density functions, estimated by the Blackmann-Tukey method, from the zero crosses and the energy envelopes of the sound data of all the piano solo pieces composed by Debussy and Ravel and played by Paul Crossley. The results are that those spectra show approximately 1/f although each has its own individual profile, that on zero cross Ravel' s meanβ-value is, although slightly, significantly smaller than Debussy' s and relatively near 1/f , and that Debussy' s mean coefficient of determination R2 of β-values is higher. This slight but significant difference may reflect the close relation of these two composers on musical style.
Letter
  • Naoki TAKEHARA, Hirohisa HASEGAWA, Yusuke TORIUMI, Tatsuhiro KIMURA, K ...
    2007 年 19 巻 3+4 号 p. 47-50
    発行日: 2007年
    公開日: 2008/03/18
    ジャーナル フリー
    In order to estimate the mental workload, electroencephalogram (EEG) was measured during the Figure Stroop Task performance from ten healthy adult voluntary participants. In the experiment, two kind of visual stimuli were prepared: congruent and incongruent stimuli (figure and number of the figure was congruent or incongruent). Participants were asked to answer the number of displayed figures by pressing designated key. In the task, two different instructions to the participants were used: (1) respond as soon as possible, and (2) respond accurately. Integrated theta component of the EEG were compared between under condition of (1) and that of (2). Relative power percentage of theta component in condition (2) was larger than that in (1). The result suggests that the theta component was related with subjective difficulty of the task.
Paper
Paper
  • Koichi HAYAKAWA, Tempei TANAKAMARU, Yusuke ONO, Yoshihito MATSUMURA
    2007 年 19 巻 3+4 号 p. 55-58
    発行日: 2007年
    公開日: 2008/03/18
    ジャーナル フリー
    Titanium nitride TiN shows considerable hydrogen impermeability and is expected as a prevention coating of hydrogen gas for a cladding tube of metal hydride fission fuel. The TiN coating produce with plasma process is very complicated because the cladding tube is not wide enough to create stable plasma. In this study, a simple reactive evaporation process was selected for coationg process of TiN films to inner wall of narrow tube. The films were thermally deposited on stainless steel sheets were coiled around inner wall of silica glass tubes. Nitrogen as a reactive gas was introduced into the vacuum chamber with pressure of 1.0×10-1 Pa. As results, thin films with gold color were obtained. From XRD measurement of films, distinct diffraction patterns of TiN phase were observed. In this syudy, a reactivity of N2 gas molecules with Ti atoms in Ti-N film formation has measured quantitatively. As results, the reaction probability of N2 molecules rN2 is defined as the ratio of the absorbing rate of N2 on Ti surface AN2 to the rate of N2 impingement ZN2. Reactive evaporation process showed rN2 ≅ 0.013. It was 1/5 of rN2 with Ti film prepared by plasma processes.
Paper
  • Toru ISOGAI, Takuma MATSUMOTO, Yuji YOSHIMURA, Hiroshi HOSHINO
    2007 年 19 巻 3+4 号 p. 59-63
    発行日: 2007年
    公開日: 2008/03/18
    ジャーナル フリー
    We know that polymer electrolyte fuel cell (PEFC) can't run for a long time without humidification. As nafion membrane's function deteriorates when hydrogen ions go through in the dried electrodes,we operated PEFC by two methods for a long time. One is a method to apply the water-soluble macromolecule that is Methyl cellulose (MC) to the surface of PEFC. Another is supply the humidified hydrogen in PEFC. We investigate that a cause of the decreasing output is the platinum catalyst of the electrode particles. It is observed that the particle size of the platinum have increased after operation compared with before operation. Also, the platinum catalyst size distribution supported on acetylene change from uniform to non-uniform. In addition to them, we confirm the resolution of MC which apply to the surface of PEFC by STEM.
    As the result, it was the confirmation that output decrease by particle size and distribution of the platinum catalysts.
Paper
  • Kazuya WADA, Haru-Hisa UCHIDA
    2007 年 19 巻 3+4 号 p. 64-67
    発行日: 2007年
    公開日: 2008/03/18
    ジャーナル フリー
    The amount of effective recovery of waste plastic in Japan was 6,110,000t in 2004. The recycling rate has been increasing from 26% in 1990 to 60% in 2004 . In this research, we have evaluated the recycling techniques from the view points of environmental impact such as CO2 emissions and amount of oil fuel reduction. For reducing the consumption of plastics and oils and reducing CO2 emission, material recycle (reproduction), energy recovery (fuel substitution and electric power generation) and chemical modification (fuel substitution and electric power generation) are compared as plastic recycles including cascade processes of utilization. As a result, material recycle is the most effective recycling in the three materials flows, because the material recycle may have few CO2 emissions while it consumes less crude oil.
Paper
  • Takehiro ISHIKAWA, Haru-Hisa UCHIDA
    2007 年 19 巻 3+4 号 p. 68-73
    発行日: 2007年
    公開日: 2008/03/18
    ジャーナル フリー
    Recycle models of used edible oil in different scales were considered from the CO2 emission induced. In the models, CO2 emission was estimated systems including the consumption of used oil as “Bio Diesel Fuel (BDF)” or fuel for direct combustion using “Biomass Burner (BMB)” . Three models from a small scale of household to a city scale with 260,000 residents were compared. Because the amount of oil collected differs in each modeles, the CO2 emission was evaluated for an unit volume of the used edible oil. In case of the use for BMB in a bath facility for 250 persons located in a shopping mall, the most reduction of CO2 emission was obtained
Paper
  • Tsuguhiro WATANABE, Kazuo TAKAYAMA, Akira TONEGAWA, Kazutaka KAWAMURA, ...
    2008 年 19 巻 3+4 号 p. 74-87
    発行日: 2008年
    公開日: 2008/03/18
    ジャーナル フリー
    A new plasma confinement method is proposed to sustain high temperature core plasma in surface magnetic field. Magnetic field is zero in core plasma region (complete β =1plasma). The bootstrap current driven by the pressure of plasma generates the magnetic field in an outside area of the plasma column. The magnetic field plays the role as the surface magnetic field to confine plasma. In addition, in an outside area of external coils, the magnetic field cancel the magnetic field produced by the external coils. It is possible, therefore, to be decreased the total energy of the system by the confinement of high beta plasma. Then, bootstrap transition to the complete β=1 plasma confinement configuration is possible if plasma is heated by sufficient power level. The possibility is confirmed by the energy computation of the magnetic field under the cylindrical coil group model. In addition, it was shown numerically by the one dimensional transport calculation, that the threshold power (lower bound) exist in the heating input to plasma for the bootstrap transition to the complete β=1 plasma confinement configuration. Moreover, detailed structure of the complete β =1 plasma confinement configuration is shown by the equilibrium calculation of an axisymmetric configuration. It is proposed that the LHD magnetic field configuration be suitable for complete β =1plasma confinement.
Paper
  • Jean-Claude CRIVELLO, Tohru NOBUKI, Shunsuke KATO, Masatake ABE, Toshi ...
    2008 年 19 巻 3+4 号 p. 88-96
    発行日: 2008年
    公開日: 2008/03/18
    ジャーナル フリー
    In the present work, the Mg-Al system was studied towards hydrogen absorption properties.
    Several MgxAl100-x compounds from X=47.5 to 70 by incremental step of 2.5 were prepared by ball-milling with post-annealing. Different experimental measurements were performed and are in mutual agreement with properties of existing phases. They show that deviation from the ideal composition of Mg17Al12 (X=58.62) leads to a decrease of the homogeneity. The single γ-phase range is extended at room temperature for initial 55≤X≤62.5 atomic % of Mg.
    The hydrogenation properties have been investigated for two compounds at the nominal composition X=50 and X=58.6. The hydrogen absorption is presented at 350°C and shows a maximum hydrogen capacity of 3.5 and 3.7 wt% respectively. For these two compounds, the pressure-composition isotherm (PCT) curves show two absorption plateaux, with equilibriums around 10 bars which are higher than that of pure MgH2. The shape discontinuity corresponds to a transformation into a 2-step process as described in this work. After final desorption, the initial compounds are recovered, indicates that the reactions are reversible.
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