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21.
Fujiwara Osamu 《电子科学学刊(英文版)》2008,25(3):384-388
Characteristic measurement of contact discharge currents are made through a hand-held metal rod from charged human body. Correlation coefficients are obtained, through Statistic Package for Social Science (SPSS), for various charge voltages, which is based on the effect test of electrode contact approach speeds on discharge current parameters of current peaks, maximum rising slope and spark lengths. Discharge parameters at charge voltage 300V are independent on approach speed. For charge voltages equal to and higher than 500V, the contact approach speed has strong positive correlation with discharge parameters of the peak current and the maximum rising slope, whereas has strong negative correlation with the spark length. 相似文献
22.
Osamu Hanaizumi Yong-Gi Lee Isao Takahashi Tomohiko Nakajo Jun-Ichi Murota Shojiro Kawakami 《Optical Fiber Technology》1995,1(4)
A laminated polarization splitter for the wavelength region longer than 1.3 μm is fabricated for the first time. It is composed of a-SiC:H/SiO2 alternative multilayers prepared by plasma-enhanced chemical vapor deposition. Splitting behavior is also verified experimentally. It has low absorption loss even for the wavelength region around λ = 1.3 μm because the band-gap energy of a-Sic is larger than that of a-Si. The measured splitting angle is 13.8°, which is 2.4 times larger than the 5.7° splitting angle of rutile. The absorption loss of the multilayer is reduced to 1 × 10-3 dB/μm at λ = 1.3 μm. The magnitude of the residual stress is 9.45 × 108 dyn/cm2, which is about one-third of that prepared by the rf bias sputtering equipment which is used for another project of our group. The deposition rate of SiO2, is increased to 135 nm/min, which is 27 times larger than that prepared by the sputtering equipment. 相似文献
23.
Chil-Woo Lee Osamu Hasegawa Wiwat Wongwarawipat Hiroshi Dohi Mitsuru Ishizuka 《Journal of Visual Communication and Image Representation》1991,2(4)
This paper describes a system that can synthesize realistic sequential images of moving goldfish based on the image understanding result of real goldfish. To analyze and synthesize images in real-time, we have constructed a hardware system that consists of 32 paralell transputers with a high-speed visual-data interface called VIT (Visual Interface for Transpputer Network). The system is very flexible and powerful for various types of image processing because it can be extended according to the required computational cost. In the understanding process, we assume that the target object, a goldfish in this case, deforms its shape pliably in 3-D space and moves only in a two-dimensional direction. A modeling, called the Bone-Structured Solid Modeler, which is suitable for representing deformable objects such as living things, plays an important role in the understanding and synthesis processes of the deformable object. Three types of constraints for motion, namely, static, dynamic, and object, are utilized to verify the estimated pose and orientation of the object. In the motion synthesis process, realistic moving images are synthesized by controlling the model employing the motion understanding result. Simulation results are presented to show the effectiveness of the system. The technology discussed in this paper is expected to play a key role in the realization of future visual human interfaces. 相似文献
24.
The paper summarises Japanese activities concerning photovoltaic systems including those for residential use, which is one of the major targets for a domestic alternative energy supply. Fiscal year 1999 marked the 25th anniversary of the Sunshine Project that was initiated in July 1974. The Sunshine Project was subsequently reorganised into the New Sunshine Program to include renewable energy, energy conservation and environmental technology. The major target of the Photovoltaic Technology Development Project in the Programme, from an early stage of R&D, has been focused on utility-connected, residential applications mounted on roofs. Recently, it can be considered that technologies for the target have been fundamentally established and a series of new activities have been introduced to promote the commercialisation and diffusion of PV systems. To review those activities, several condensed tables are presented, i.e., R&D history of residential applications, recent trends in regulation and code improvements, and new institutional activities to disseminate PV systems. The authors also present performance results collected from a large number of PV systems by using a very effective evaluation method called the ‘SV method’. The paper finishes by introducing a good example of simple system monitoring with good verification that can establish a knowledge circle from a variety of PV fields, including to factories, engineers, owners and investors, and it seems to be quite cost-effective. 相似文献
25.
Hydrogen is a clean alternative to conventional hydrocarbon fuels, but it is very important to reduce the nitrogen oxides (NOx) emissions generated by hydrogen combustion. The rich-lean combustion or staged combustion is known to reduce NOx emissions from continuous combustion burners such as gas turbines and boilers, and NOx reduction effects have been demonstrated for hydrocarbon fuels. The authors applied rich-lean combustion to a hydrogen gas turbine and showed its NOx reduction effect in previous research. The present study focused on experimental measurements of NO and NO2 emissions from a coaxial rich-lean burner fueled with hydrogen. The results were compared with diffusion combustion and methane rich-lean combustion. Significant reductions in NO and NO2 were achieved with rich-lean combustion. The NO and NO2 reduction effects by rich-lean combustion relative to conventional diffusion combustion were higher with hydrogen than with methane. 相似文献
26.
Overview on Technical Issues for Future Mobile Network and a Proposal of DLC Scheme in Wireless Link
This paper gives an overview on technical issues for future mobile networks. the QoS control for multimedia services, security function, expansion of network capacity, expansion of address space, multicast function, radio link quality and mobility control of terminals are taken up as technical issues.Then, a novel DLC scheme in wireless link named EREP-ARQ (Estimation and Report of Error Pattern ARQ) which can reduce the retransmission ratio is proposed. In this scheme, error pattern generated in the radio link is estimated at the receiver side and the estimated error pattern is returned to the transmission side. If the estimation is correct, no retransmission is needed. Compared to conventional SR-ARQ, throughput can be improved by17% and Cell Loss Ratio (or Packet Loss Rate) can be reduced to less than 1/10 by the proposed EREP-ARQ. 相似文献
27.
Jun-ichi Nishizawa Akihiko Murai Hiroki Makabe Osamu Ito Tomoyuki Kimura Ken Suto Yutaka Oyama 《Solid-state electronics》2004,48(12):2251-2254
The tunnel injection transit time (TUNNETT) diodes with p+p+n+n−n+ structure were fabricated by liquid phase epitaxy (LPE). About 100 Å tunnel junction (p+n+) was successfully prepared by the double impurity diffusion of Ge and S during LPE growth. Continuous wave (CW) oscillation was realized at 51.520 GHz in the V-band cavity with the phase noise of −60 dBc/Hz at 1 kHz bandwidth. 相似文献
28.
Wataru Tamura Arata Yasuda Ken Suto Masasuke Hosokawa Osamu Itoh Jun-Ichi Nishizawa 《Journal of Electronic Materials》2003,32(10):1079-1084
Effects of Bi doping in PbTe liquid-phase epitaxial layers grown by the temperature difference method under controlled vapor
pressure (TDM-CVP) are investigated. For Bi concentrations in the solution, xBi, lower than 0.2 at.%, an excess deep-donor level (activation energy Ed≈0.03–0.04 eV) appears, and Hall mobility is low. In contrast, for xBi>0.2 at.%, Hall mobility becomes very high, while carrier concentration is in the range of 1017 cm−3. Inductive coupled plasma (ICP) emission analysis shows that, for xBi=1 at.%, Bi concentration in the epitaxial layer is as high as NBi=2.3–2.7 × 1019 cm−3. These results indicate that Bi behaves not only as a donor but also as an acceptor, and the nearest neighbor or very near
donor-acceptor (D-A) pairs are formed, so that strong self-compensation of Bi takes place. Carrier concentration for highly
Bi-doped layers shows a minimum at a Te vapor pressure of 2.2 × 10−5 torr for growth temperature 470°C, which is coincident with that of the undoped PbTe. 相似文献
29.
Maehara Fumiaki Nakamura Osamu Takanashi Hitoshi 《Wireless Personal Communications》2000,15(3):181-197
We propose a novel SIR weighting postdetection combining diversity scheme with a new accurate SIR estimation method. The SIR is estimated and used as the weighting factor to compensate severe cochannel interference, one of the most important issues for PCS in terms of frequency utilization. Theimprovement offered by the proposal depends on SIR estimation accuracy.The SIR is, in this paper, estimated by a matched filter where theauto-correlation between received signal and unique word is calculated. Computer simulationsconfirm that the SIR of each diversity branch can be estimated easily andaccuratelyby the proposed SIR estimation method. The proposed diversity scheme achievesaperformance very close to that of ideal SINR weighting diversity underRayleighfading with severe cochannel interference. When average SIR = 10 dB and thenumber of branches(L)=4, the proposed diversity scheme lowers the requiredEb/N0 by 5 dB at BER = 1×10-3compared to conventional maximal ratio combining diversity. This paper alsopresentsthe unique word length required to realize adequate performance, i.e.,robustnessagainst high-pitch Rayleigh fading. 相似文献
30.
The authors have proposed a method of reducing the energy consumption in residential buildings by providing household members with information on energy consumptions in their own houses. An on-line interactive “energy-consumption information system” that displays power consumptions of, at most, 18 different appliances, power and city-gas consumption of the whole house and room temperature, for the purpose of motivating energy-saving activities has been constructed and the effectiveness of the system investigated by installing it in 10 residential buildings. The experiment showed that energy-saving consciousness was raised and energy consumption was in fact reduced by the energy-saving activities of the household members. In this paper, the system is described in detail and the effectiveness of reducing energy-consumption of the whole house and for space heating will be discussed. Also the energy-saving activities in a certain household are shown by using load duration curves. 相似文献