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71.
Masashi Asuka Kenji Kataoka Kiyotoshi Komaya Syogo Nishida 《Electrical Engineering in Japan》2011,175(3):65-73
In this paper, we present an automatic train control method adaptable to disturbed train traffic conditions. The proposed method presumes transmission of detected time of a home track clearance to trains approaching the station by employing equipment of Digital ATC (Automatic Train Control). Using the information, each train controls its acceleration by a method that consists of two approaches. First, by setting a designated restricted speed, the train controls its running time to arrive at the next station in accordance with predicted delay. Second, the train predicts the time at which it will reach the current braking profile generated by Digital ATC, along with the time when the braking profile transits ahead. By comparing them, the train correctly chooses the coasting drive mode in advance to avoid deceleration due to the current braking profile. We evaluated the effectiveness of the proposed method regarding driving conditions, energy consumption, and reduction of delays by simulation. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(3): 65–73, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.10020/eej.21080 相似文献
72.
Yoshinori Nishida Norihisa Izawa Yukio Kuramasu 《Metallurgical and Materials Transactions A》1999,30(3):839-844
Separation of matrix metals in composites was tried on alumina short fiber-reinforced aluminum and 6061 alloy composites and
SiC whisker-reinforced 6061 alloy composite for recycling. It is possible to separate molten matrix metals from fibers in
the composites using fluxes that are used for melt treatment to remove inclusions. About 50 vol pct of the matrix metals was
separated from the alumina short fiber-reinforced composites. The separation ratio of the matrix from the SiC whisker-reinforced
6061 alloy composite was low and about 20 vol pct. The separation mechanism was discussed thermodynamically using interface
free energies. Since the flux/fiber interface energy is smaller than the aluminum/fiber interface energy, the replacement
of aluminum with fluxes in composites takes place easily. Gases released by the decomposition of fluxes act an important role
in pushing out the molten matrix metal from the composite. The role was confirmed by the great amount cavity formed in the
composite after the matrix metal flowed out. 相似文献
73.
Modeling of NBTI saturation effect and its impact on electric field dependence of the lifetime 总被引:1,自引:0,他引:1
H. Aono E. Murakami K. Okuyama A. Nishida M. Minami Y. Ooji K. Kubota 《Microelectronics Reliability》2005,45(7-8):1109-1114
Negative Bias Temperature Instability of pMOSFETs is investigated under various stress gate voltages and temperatures. It is shown that degradation tends to saturate and the dependence of lifetime on electric field (Eox) is expressed as a power-law of Eox. We propose new empirical and kinetic models. The Eox dependence of the lifetime described by the power-law is derived from our empirical model describing the saturation of degradation. Moreover, our kinetic model explains the saturation behavior. 相似文献
74.
Characteristics of the Mach Disk in the Underexpanded Jet in which the Back Pressure Continuously Changes with Time 总被引:1,自引:0,他引:1
When the high-pressure gas is exhausted to the vacuum chamber from the nozzle, the underexpanded supersonic jet contained with the Mach disk is generally formed. The eventual purpose of this study is to clarify the unsteady phenomenon of the underexpanded free jet when the back pressure continuously changes with time. The characteristic of the Mach disk has been clarified in consideration of the diameter and position of it by the numerical analysis in this paper. The sonic jet of the exit Mach number Me=1 is assumed and the axisymmetric conservational equation is solved by the TVD method in the numerical calculation. The diameter and position of the Mach disk differs with the results of a steady jet and the influence on the continuously changing of the back pressure is evidenced from the comparison with the case of steady supersonic jet. 相似文献
75.
K Kobayashi M Endo H Nishida Y Tomizawa H Satoh H Koyanagi 《Canadian Metallurgical Quarterly》1998,46(9):878-881
The extramammary Paget's disease of anogenital area is rare, and is seen as a precancerous lesion or carcinoma in situ. In most cases, surgical treatment including dissection of regional lymph nodes, skin resection and grafting should be considered first. A 74-year-old male suffered from effort angina and underwent triple coronary artery bypass grafting (CABG) including saphenous vein graft (SVG) harvested from right lower leg. Five years previously he underwent skin grafting for extramammary Paget's disease of both inguinal areas and the perineal area. The postoperative course was uneventful and he was discharged 23 days after the CABG operation. Extramammary Paget's disease is localized in epidermis for years and there has been no report of direct invasion into vessels. Therefore, there appears to be no reason not to use an SVG if there is no luminal thrombus or occlusion. 相似文献
76.
A correlated double sampling technique, applicable to continuous-time active-RC filters, is proposed. It provides suppression of DC offset and 1/f noise, and performs gain boosting and level shifting for the opamps used. A biquad lowpass filter is described to demonstrate the application of the technique. 相似文献
77.
A new brain-computer interface design using fuzzy ARTMAP 总被引:5,自引:0,他引:5
Palaniappan R. Paramesran R. Nishida S. Saiwaki N. 《IEEE transactions on neural systems and rehabilitation engineering》2002,10(3):140-148
This paper proposes a new brain-computer interface (BCI) design using fuzzy ARTMAP (FA) neural network, as well as an application of the design. The objective of this BCI-FA design is to classify the best three of the five available mental tasks for each subject using power spectral density (PSD) values of electroencephalogram (EEG) signals. These PSD values are extracted using the Wiener-Khinchine and autoregressive methods. Ten experiments employing different triplets of mental tasks are studied for each subject. The findings show that the average BCI-FA out- puts for four subjects gave less than 6% of error using the best triplets of mental tasks identified from the classification performances of FA. This implies that the BCI-FA can be successfully used with a tri-state switching device. As an application, a proposed tri-state Morse code scheme could be utilized to translate the outputs of this BCI-FA design into English letters. In this scheme, the three BCI-FA outputs correspond to a dot and a dash, which are the two basic Morse code alphabets and a space to denote the end (or beginning) of a dot or a dash. The construction of English letters using this tri-state Morse code scheme is determined only by the sequence of mental tasks and is independent of the time duration of each mental task. This is especially useful for constructing letters that are represented as multiple dots or dashes. This combination of BCI-FA design and the tri-state Morse code scheme could be developed as a communication system for paralyzed patients. 相似文献
78.
Algebraic description of curve structure 总被引:2,自引:0,他引:2
Nishida H. Mori S. 《IEEE transactions on pattern analysis and machine intelligence》1992,14(5):516-533
79.
S Nishida M Nakamura S Suwazono M Honda H Shibasaki 《Canadian Metallurgical Quarterly》1997,104(5):431-436
Lengthening is generally accepted method of treatment for extremity length discrepancy. This attractive method carries the risk of many complications that may ruin primary treatment plan. The aim of this paper was to analyze complications and their management in own material consisting of 60 extremities in 58 patients aged 8-37 years. Limb length discrepancy was caused by congenital bony hypoplasia in 44 cases, trauma in 8 and infection in 8 cases. Initial shortening ranged from 4 to 15 cm (mean 6.5 cm). Ilizarov technique was used in 20 cases, Wagner method in 6 cases and DeBastiani in 34 cases. Expected elongation has been achieved in 60% cases; in remaining 40% complications occurred. New bone formation disturbances and axial malalignement were among most severe ones. An autogenic marrow injections were used to stimulate callus formation, osteogenon was administered. Axial malalignement was corrected by osteotomy. Percentage of complications decreased as number of elongations performed increased. 相似文献
80.
Yamada M. Mori A. Kobayashi K. Ono H. Kanamori T. Oikawa K. Nishida Y. Ohishi Y. 《Photonics Technology Letters, IEEE》1998,10(9):1244-1246
We describe a tellurite-based Er3+-doped fiber amplifier (EDFA) with a flat amplification bandwidth of 76 nm and a noise figure of less than 7 dB. Furthermore, a parallel-type amplifier composed of this EDFA and a 1.45-μm-band Tm3+-doped fluoride fiber amplifier achieved a flat amplification bandwidth of 113 nm 相似文献