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121.
In previous papers, the authors introduced the wireless transmission of power and information (WTPI) for realizing a future manufacturing system which is free from the complexity of wiring for the power supply or control. In extension from these studies, the authors have attempted to apply the linear-type WTPI for realizing the maintenance-free drive and the multimover operation of a moving coil-type linear motor. This paper describes the basic concept of the WTPI and the analysis on the performance of the WTPI configured in the linear shape, thereafter introducing the preliminary test result on a prototype of the cableless linear pulse motor (CLLPM) which was constructed by integrating a linear pulse motor (LPM) with the associated driver and the linear WTPI for noncontact motion transfer 相似文献
122.
This paper deals with a dynamic voltage restorer (DVR) characterized by installing the shunt converter at the load side. The DVR can compensate for the load voltage when a voltage sag appears in the supply voltage. An existing DVR requires a large capacitor bank or other energy‐storage elements such as double‐layer capacitors or batteries. The DVR presented in this paper requires only a small DC capacitor intended for smoothing the DC‐link voltage. Moreover, three control methods for the series converter are compared and discussed to reduce the series‐converter rating, paying attention to the zero‐sequence voltages included in the supply voltage and the compensating voltage. Experimental results obtained from a 200‐V, 5‐kW laboratory system are shown to verify the viability of the system configuration and the control methods. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 165(3): 73–82, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20460 相似文献
123.
Zahrul Fuadi Koshi Adachi Hideaki Ikeda Hisataka Naito Koji Kato 《Tribology Letters》2009,33(3):169-178
In this paper, a fundamental mechanism for creep-groan generation is investigated by adopting a simple yet effective caliper-slider
experimental model. Contact condition, which is a function of three parameters, namely normal force, contact roughness, and
material combination, is connected with the creep-groan phenomenon in terms of contact stiffness. Creep-groan generation is
determined by analyzing the frequency characteristic of the generated vibration acceleration when the sliding commences due
to a simultaneous application and release of force in the tangential and normal directions, respectively. As per the obtained
results, creep-groan occurrence or absence in the employed experimental model may be classified into three regions based upon
the value of the contact stiffness, i.e., occurrence, non-occurrence, and mixed regions. The results also indicate that creep-groan
occurrence in this caliper-slider experimental model can be avoided by controlling the value of contact stiffness in an effective
manner. 相似文献
124.
M. Mori Y. Kagami S. Kanemoto T. Tamaoki M. Enomoto S. Kawamura 《Progress in Nuclear Energy》2005,46(3-4):241-252
A new method for estimating reactivity parameters, such as moderator temperature coefficient (MTC) and void reactivity coefficient (VRC), is proposed using steady-state noise data. In order to solve the ill-posed problem of reactivity parameter estimation, a concept of a gray box model is newly introduced. The gray box model includes a first principle based model and a black-box fitting model. The former model acts as a priori knowledge based constraints in a parameter estimation problem. After establishing the gray box and noise source models, the maximum likelihood estimation method based on Kalman filter is applied. Furthermore, it is shown that the frequency domain approach of the gray box model is useful in the case of VRC estimation. The effectiveness of the proposed algorithms is shown through numerical simulation and actual plant data analysis. 相似文献
125.
Noninvasive Measurement of the Volume Elastic Modulus in Finger Arteries Using Photoelectric Plethysmography 总被引:2,自引:0,他引:2
Shimazu Hideaki Yamakoshi Ken-Ichi Kamiya Akira 《IEEE transactions on bio-medical engineering》1986,(8):795-798
A method for the nonivasive measurement of the volume elastic modulus (Ev) in human finger arteries was developed. The volume change ratio and pulse pressure in the arteries were simultaneously determined by a transmittance type infrared photoelectric plethysmograph and a volume oscillometric sphygmomanometer using an occlusive cuff. The Ev values could be obtained at a desired transmural pressure level of the arteries which was controlled by the cuff. A clear difference was revealed between the Ev values obtained in the fingers of two male subjects of 33 and 65 years old. The values determined by this method were compared to those calculated from pulse wave propagation velocity (Evp) obtained simultaneously in the fingers of 11 subjects. The linear regression equation was Ev = 1.31 Evp ?0.117 with a correlation coefficient r = 0.893 (n = 39). These results suggest that this should be a useful and noninvasive method of evaluating changes in arterial elasticity accompanying aging and perhaps influenced by accompanying hypertension or arteriosclerosis. 相似文献
126.
127.
Tsuyoshi Kawai Akihiro Kubota Kensuke Kawamura Hiroyuki Tsumatori Takuya Nakashima 《Thin solid films》2008,516(9):2666-2669
Diffusion kinetics of three dyes in nematic liquid crystals are studied with single-molecule fluorescence autocorrelation spectroscopy. Markedly large anisotropy was observed in the diffusion coefficient and structure of diffusion molecules showed no marked effect on the anisotropy. 相似文献
128.
Hori Tetsuya; Moriyama Hideaki; Kawaguchi Jitsutaro; Hayashi-Iwasaki Yoko; Oshima Tairo; Tanaka Nobuo 《Protein engineering, design & selection : PEDS》2000,13(8):527-533
A temperature-jump (T-jump) time-resolved X-ray crystallographictechnique using the Laue method was developed to detect small,localized structural changes of proteins in crystals exposedto a temperature increase induced by laser irradiation. In achimeric protein between thermophilic and mesophilic 3-isopropylmalatedehydrogenases (2T2M6T), the initial structural change uponT-jump to a denaturing temperature (~90°C) was found tobe localized at a region which includes a ß-turn and aloop located between the two domains of the enzyme. A mutant,2T2M6T-E110P/S111G/S113E, having amino acid replacements inthis ß-turn region with the corresponding residues ofthe thermophilic enzyme, showed greater stability than the originalchimera (increase of Tm by ~10°C) and no T-jump-inducedstructural change in this region was detected by our method.These results indicate that thermal unfolding of the originalchimeric enzyme, 2T2M6T, is triggered in this ß-turn region. 相似文献
129.
130.
Wakita K. Kawamura Y. Yoshikuni Y. Asahi H. Uehara S. 《Quantum Electronics, IEEE Journal of》1986,22(9):1831-1836
The first measurements to be made of large anistropic electroabsorption and modulation of long-wavelength light propagating along the plane of InGaAs/InAlAs multiple quantum well (MQW) structures grown by molecular beam epitaxy (MBE) are reported. Photocurrent response of waveguide p-i-n diodes is studied for incident light polarization parallel and perpendicular to the MQW layers. Photocurrent increase with reverse bias throughout the entire photoresponse spectrum is observed for both polarizations. The MQW p-in optical modulator shows a capacitance-limited pulse response of 250 ps and the modulation depth is 14 percent. 相似文献