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Koji YAMASHITA Osamu FUJIWARA Kazuo KATOH Takashi AZAKAMI
This letter presents a method for estimating the discontact rate by the pantograph noise current using a statistical test. This method requires no apriori information on the current collection system used in the previous methods. The experiment is performed to verify the validity of the above method.
Takeshi KONDOH Osamu FUJIWARA Kazuo KATOH Takashi AZAKAMI
This letter presents a method for real-time visualization of static electricity distribution which can be achieved by rapidly measuring the voltages induced on the array electrodes. For verifying the validity of this method, the measurement examples on the charged sheets are demonstrated.
The state of the art of low-voltage (LV) analog circuit design techniques is reviewed, and fundamental design techniques are identified and classified as follows: 1) current-mode, 2) series-to-parallel, 3) signal range sharing, 4) dynamic bias, 5) linear bias, and 6) LV regulator. A relatively wide variety of low frequency application circuits have been developed, but future development is expected for wide-bandwidth application circuits such as a voltage-controlled-oscillator (VCO), a balanced multiplier, etc. The circuit techniques such as current-mode, signal range sharing, and dynamic bias will probably be most important for advanced future circuit designs.
Kazuo KATO Satoshi YASUKAWA Kazunori SUZUKI Atsuo ISHIKAWA
The purpose of this study was to identify the key variables that determine the quality of the auditory environment, for the purposes of workplace auditory design and assessment. To this end, we characterized changes in oscillatory neural activity in electroencephalographic (EEG) data recorded from subjects who performed an intellectual activity while exposed to fluctuating ambient noise. Seven healthy men participated in the study. Subjects performed a verbal and spatial task that used the 3-back task paradigm to study working memory. During the task, subjects were presented with auditory stimuli grouped by increasing high-frequency content: (1) a sound with frequencies similar to Brownian noise and no modulation; (2) an amplitude-modulated sound with frequencies similar to white noise; (3) amplitude-modulated pink noise; and (4) amplitude-modulated Brownian noise. Upon presentation, we observed a characteristic change in three EEG bands: theta (4-8Hz), alpha (8-13Hz), and beta (13-30Hz). In particular, a frequency-dependent enhancement and reduction of power was observed in the theta and beta bands, respectively.
Ichiro HIROSAWA Tetsuo HONMA Kazuo KATO Naoto KIJIMA Yasuo SHIMOMURA
The sites that doped divalent Eu ions occupy in BaMgAl10O17 were studied by X-ray absorption fine structure (XAFS) measurement. The radial structural function and the Fourier-filtered EXAFS wiggle derived from the observed XAFS spectrum suggested that Eu ions occupy the Beevers-Ross and/or anti-Beevers-Ross sites. Observed XANES spectrum also could be explained by Beevers-Ross site occupation.
Takeshi KONDOH Osamu FUJIWARA Kazuo KATOH Takashi AZAKAMI
This letter presents a method for visualizing the 2-dimensional distribution of electrostatic charge, which is based on the principle of the X-ray CT. For confirming the possibility of this method, the focusing images of the simple model are also demonstrated by a computer computation.
Masahiro ISHIKAWA Osamu FUJIWARA Kazuo KATOH Takashi AZAKAMI
For the effectively therapeutic conditions of laser acupuncture, as a first step, this letter examines the thermal stress inside the skin tissue produced by laser acupuncture. A method is presented of calculating the 3-dimensional thermal stress. The numerical results are also shown.
Souichi TSUKAMOTO Osamu FUJIWARA Kazuo KATOH Takashi AZAKAMI
This letter describes the occurrence-frequencies of the microarcs in the carbon sliding-contacts which are known to give the low radio-noises. A method is presented for statistically evaluating the arc occurrence-frequencies. The measurement results are also shown.