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排序方式: 共有3719条查询结果,搜索用时 15 毫秒
51.
Takakuni Douseki Takeshi Yamada Junzo Yamada Kazuyuki Ito Kazuo Nishi 《Solar Energy Materials & Solar Cells》2001,67(1-4)
We have developed a mobile global positioning system (GPS) that operates on just photovoltaic (PV) cells. The system receives wireless signals from satellites and shows one's present location accurately on a map without the need for a battery. A PV display module, which combines a transparent LCD with a-Si PV cells and has a power generation function, is added to ordinary PV cells to increase the total amount of power generated. The PV display module enables 40% more power generation than a system without the module. 相似文献
52.
Kazuhiko Kato Takeshi Hibino Keiichi Komoto Seijiro Ihara Shuji Yamamoto Hideaki Fujihara 《Solar Energy Materials & Solar Cells》2001,67(1-4)
Authors have evaluated the life cycle of a thin-film CdS/CdTe PV module to estimate the energy payback time (EPT) and the life-cycle CO2 emissions of a residential rooftop PV system using the CdS/CdTe PV modules. The primary energy requirement for producing 1 m2 of the CdS/CdTe PV module was similar to a-Si PV module at annual production scale of 100 MW. EPT was calculated at 1.7–1.1 yr, which was much shorter than the lifetime of the PV system and similar to that of a-Si PV modules. The life-cycle CO2 emissions were also estimated at 14–9 g-C/kWh, which was less than that of electricity generated by utility companies. 相似文献
53.
Kohei Miyazaki Naotsugu Sugimura Koji Matsuoka Yasutoshi Iriyama Takeshi Abe Masao Matsuoka Zempachi Ogumi 《Journal of power sources》2008
Carbon-supported La1−xSrxMnO3 (LSM/C) was prepared by reversible homogeneous precipitation method, and its catalytic activities for oxygen reduction under the existence of ethylene glycol (EG) were investigated by using rotating disk electrode. LSM/C exhibited the high activity for oxygen reduction irrespective with the presence of EG, indicating that EG is not oxidized by LSM/C at the cathode side in the present system. Consequently, LSM/C can serve as a cathode catalyst in alkaline direct alcohol fuel cells with no crossover problem. Performance test for fuel cells operation also supported these results and showed cathodic polarization curves were not affected by the concentration of EG supplied to anode even at 5 mol dm−3. 相似文献
54.
Takeshi Kobayashi Yuki Imade Daisuke Shishihara Kenji Homma Miki Nagao Ryota Watanabe Toshiyuki Yokoi Atsuo Yamada Ryoji Kanno Takashi Tatsumi 《Journal of power sources》2008
A high-capacity type of all solid-state battery was developed using sulfur electrode and the thio-LISICON electrolyte. New nano-composite of sulfur and acetylene black (AB) with an average particle size of 1–10 nm was fabricated by gas-phase mixing and showed a reversible capacity of 900 mAh g−1 at a current density of 0.013 mA cm−2. 相似文献
55.
This paper introduces a new concept of testability called consecutive testability and proposes a design-for-testability method for making a given SoC consecutively testable based on integer linear programming problem. For a consecutively testable SoC, testing can be performed as follows. Test patterns of a core are propagated to the core inputs from test pattern sources (implemented either off-chip or on-chip) consecutively at the speed of system clock. Similarly the test responses are propagated to test response sinks (implemented either off-chip or on-chip) from the core outputs consecutively at the speed of system clock. The propagation of test patterns and responses is achieved by using interconnects and consecutive transparency properties of surrounding cores. All interconnects can be tested in a similar fashion. Therefore, it is possible to test not only logic faults but also timing faults that require consecutive application of test patterns at the speed of system clock since the consecutively testable SoC can achieve consecutive application of any test sequence at the speed of system clock. 相似文献
56.
Inaba S. Okano K. Matsuda S. Fujiwara M. Hokazono A. Adachi K. Ohuchi K. Suto H. Fukui H. Shimizu T. Mori S. Oguma H. Murakoshi A. Itani T. Iinuma T. Kudo T. Shibata H. Taniguchi S. Takayanagi M. Azuma A. Oyamatsu H. Suguro K. Katsumata Y. Toyoshima Y. Ishiuchi H. 《Electron Devices, IEEE Transactions on》2002,49(12):2263-2270
The 35 nm gate length CMOS devices with oxynitride gate dielectric and Ni salicide have been fabricated to study the feasibility of higher performance operation. Nitrogen concentration in gate oxynitride was optimized to reduce gate current I/sub g/ and to prevent boron penetration in the pFET. The thermal budget in the middle of the line (MOL) process was reduced enough to realize shallower junction depth in the S/D extension regions and to suppress gate poly-Si depletion. Finally, the current drives of 676 /spl mu/A//spl mu/m in nFET and 272 /spl mu/A//spl mu/m in pFET at V/sub dd/=0.85 V (at I/sub off/=100 nA//spl mu/m) were achieved and they are the best values for 35 nm gate length CMOS reported to date. 相似文献
57.
Takeshi Ohbuchi Fujihiko Matsumoto 《Analog Integrated Circuits and Signal Processing》2013,75(2):257-266
For medical devices, low frequency and low power applications are required, and a transconductor which has a low transconductance is needed. A conventional current division scheme for the low transconductance wastes operating current. This paper proposes an improved local-feedback MOS transconductor operating in subthreshold region. The proposed transconductor is optimally designed using maximally flat approximation method, Newton-Raphson method, and Downhill simplex method. From the optimization, two optimum values are obtained. Characteristics of the proposed transconductor are confirmed by simulation. Transfer characteristics of the proposed transconductor are linear, and the power consumption of the proposed transconductor is 1/60 as compared with the presented transconductor using current division scheme. The CMRR is around 70 dB, and the THD is lower than ?55 dB under a condition of that the frequency of the sinusoidal input is 100 Hz. As a demonstration of an application, the proposed transconductor is applied to a low frequency second order Butterworth filter. A cutoff frequency of the filter is 100 Hz. Simulation results show validities and availability of the proposed transconductor. 相似文献
58.
Access and metro networks based on WDM technologies 总被引:3,自引:0,他引:3
Iwatsuki K. Jun-ichi Kani Suzuki H. Fujiwara M. 《Lightwave Technology, Journal of》2004,22(11):2623-2630
This paper describes the technical issues of access and metro networks based on wavelength division multiplexing (WDM) technologies, some solutions, and an experimental demonstration. A WDM star access network with colorless optical network units (ONUs) is proposed. For realizing the colorless ONU, two approaches are introduced; optical carrier supply and spectrum slicing. In addition, a WDM metro ring network with scalable optical add/drop multiplexers (OADMs), namely the tapped-type OADM, is proposed to effectively accommodate the large amount of traffic issued from access networks. Prototypes are constructed and used to verify the feasibility of the proposed WDM technologies. 相似文献
59.
Hosokawa F Tomita T Naruse M Honda T Hartel P Haider M 《Journal of electron microscopy》2003,52(1):3-10
A spherical aberration (Cs)-corrected 200 kV TEM was newly developed. The column of the microscope was extended by 25 cm and the inner yoke of the objective lens was modified to insert some parts of the corrector elements. The corrector has two hexapole elements that play a main role in Cs correction and they are placed at a position equivalent to the coma-free point of the objective lens by using two transfer doublet lenses. The Cs correction was successfully carried out by means of the third-order aberration that was generated in the two extended hexapoles. The Cs can be corrected to the desired value and also can be overcompensated in order to produce a negative Cs, as with the corrected Cs of -23 microm shown in this work. The optical system of the corrector does not produce second- and fourth-order aberrations, and can correct residual aberrations up to the third order. All of the corrector elements are computer-controlled and the third-order aberrations are quite stable after they are properly corrected. The resolution of 0.135 nm was experimentally confirmed by the Young's fringe method. Image simulations of a silicon [110] single crystal were made with various Cs and defocus values to demonstrate the effectiveness of arbitral control of Cs. 相似文献
60.
Comparisons of computed mobile phone induced SAR in the SAM phantom to that in anatomically correct models of the human head 总被引:1,自引:0,他引:1
Beard B.B. Kainz W. Onishi T. Iyama T. Watanabe S. Fujiwara O. Jianqing Wang Bit-Babik G. Faraone A. Wiart J. Christ A. Kuster N. Ae-Kyoung Lee Kroeze H. Siegbahn M. Keshvari J. Abrishamkar H. Simon W. Manteuffel D. Nikoloski N. 《Electromagnetic Compatibility, IEEE Transactions on》2006,48(2):397-407
The specific absorption rates (SAR) determined computationally in the specific anthropomorphic mannequin (SAM) and anatomically correct models of the human head when exposed to a mobile phone model are compared as part of a study organized by IEEE Standards Coordinating Committee 34, Sub-Committee 2, and Working Group 2, and carried out by an international task force comprising 14 government, academic, and industrial research institutions. The detailed study protocol defined the computational head and mobile phone models. The participants used different finite-difference time-domain software and independently positioned the mobile phone and head models in accordance with the protocol. The results show that when the pinna SAR is calculated separately from the head SAR, SAM produced a higher SAR in the head than the anatomically correct head models. Also the larger (adult) head produced a statistically significant higher peak SAR for both the 1- and 10-g averages than did the smaller (child) head for all conditions of frequency and position. 相似文献