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排序方式: 共有1397条查询结果,搜索用时 31 毫秒
91.
Takaki K. Kanesawa K. Mukaigawa S. Fujiwara T. Go T. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2007,14(4):834-845
Characteristics of a pulse corona reactor driven by an inductive energy storage (IES) pulsed power generator are described in this paper with focusing on the influence of streamer-to-glow transition on NO removal efficiency. A pulsed high voltage with a short rise time of under 30 ns is employed to generate streamer discharges homogeneously in whole the discharge region. Fast recovery diodes are used as semiconductor opening switch (SOS) to shorten the rise time. The various resistors are employed as dummy load to clarify a suitable circuit parameter such as the capacitance of a primary energy storage capacitor and/or the inductance of a secondary energy storage inductor. The energy transfer efficiency of the pulsed power generator has a maximum value of 50% at 714 Omega dummy load resistance. A co-axial cylinder type discharge chamber was used as the corona discharge plasma reactor driven by the IES pulsed power generator. The pulsed power generator supplies 30 kV pulse with 300 pps repetition rate. The co-axial cylinder plasma reactor consists of 1 mm diameter tungsten wire and 19 mm i.d. copper tube with 30 cm length. NO removal from the simulated diesel engine exhaust gas (N2:O2=9:1, Initial NO concentration=200 ppm) increased with input energy into the reactor. The energy efficiency for NO removal was obtained to be 25 g/kWh at 30 % removal in gas flow rate of 2 L/min. However, the energy efficiency decreased to 5 g/kWh with increasing capacitance of the primary capacitor from several hundreds pF to several nF. This decrease was caused by a streamer-to-glow transition. The efficiency was affected by oxygen concentration in the gas mixture. 相似文献
92.
Fan Shi Moju Zhao Tomoki Anzai Keita Ito Xiangyu Chen Shunichi Nozawa 《Advanced Robotics》2013,27(19):971-984
Transformable multi-links aerial robots have great potentials in application relying on the transformable features to change its shape during the flight. Compared to traditional quadrotor robots, transformable multi-links robots are equipped with servo motor between links. To simplify the non-linear dynamic system, the previous work restricts the robot to transform in very slow speed so that the robot could be approximated as a quadrotor robot at each time point. However, tradeoff comes as the dynamic performance is given up. In this paper, we come up with a new framework combining of computationally efficient non-linear model predictive controller and motion primitive to optimize thrust force and joints trajectory of the multi-links aerial robot. Finally, we verify our framework with fast transformation motions and table tennis task which requires dynamic performance. 相似文献
93.
Satoshi Fukuta Keita Ogawa Masaki Nomura Mariko Yamasaki Yasutoshi Sasaki 《Holz als Roh- und Werkstoff》2017,75(3):429-437
In this study, the potential of wood-only (metal-free) load-bearing walls was proposed and tested based on the idea of using the same type of material throughout wherever possible while improving basic properties such as strength, sound insulation, and heat insulation. Specifically, a technique was tested of combining pressure sensitive adhesive tape and wood dowels in place of nails for load-bearing structures with panel reinforcement represented by wood-frame construction. For this paper, its strength was evaluated by conducting in-plane shear tests, which revealed that the initial rigidity and maximum load of the proposed test specimens were greater than that of specimens using nails for jointing. However, the shear load factor, which is calculated based on some strength parameters and which forms the foundation of housing strength design, was slightly lower than that of the nail-jointed specimen. This was because there was a large decline in post-collapse resistance and a lower calculated absorbed energy caused by brittleness. The early detachment of panels was also revealed as a problem in the tests. 相似文献
94.
Kiyoshi Minoura Shigeaki Mizushima Yasushi Asaoka Ichiro Ihara Eiji Satoh Sayuri Fujiwara Yasuhisa Itoh 《Journal of the Society for Information Display》2008,16(1):129-136
Abstract— A novel reflective color LCD without polarizers has been developed using a PDLC film and a retro‐reflector. Bright color images including moving images are achievable with ambient light. This novel LCD will enable the new application area of electronic paper. 相似文献
95.
Haijun Jia Hiroshi Kuraseko Hiroyuki Fujiwara Michio Kondo 《Solar Energy Materials & Solar Cells》2009,93(6-7):812-815
For fast deposition of microcrystalline silicon (μc-Si:H) films, a microwave-induced high-density plasma source is developed. By using this plasma source, highly crystallized μc-Si:H films can be deposited from SiH4+He plasma without even using H2 dilution and substrate heating. A systematic deposition study shows that the film deposition rate increases with increase in the input microwave power and the SiH4 flow rate. The film crystallinity also improves with power but degrades with increase in the SiH4 flux. After optimizing the plasma conditions, the deposition of a highly crystallized μc-Si film has been realized at an ultrafast deposition rate higher than 700 nm/s. 相似文献
96.
97.
N. Fujiwara A. Ogaw Yu. Pestov R. Sugahara 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》1985,240(2):275-283
Characteristics of fast pulse propagation in a large planar spark counter (PSC) are simulated using a pulser located inside the spark gap. Besides the main mode of pulse propagation, three undesirable modes are observed. These latter strongly distort the shape of the pulse. Characteristics of these modes and methods to eliminate their effects are demonstrated. We present an electrical design for a 120 cm spark counter along with some of its electrical properties as revealed by measurements made with the inner spark pulser. In the present counter design the charge of a pulse is shared by several neighboring strips, enabling one to measure the transverse position of a spark to a high degree of accuracy. 相似文献
98.
Xunwen Xiao Jianghua Fang Jin Zhou Haoqi Gao Hideki Fujiwara Toyonari Sugimoto 《Synthetic Metals》2010,160(23-24):2413-2416
Crystal structure, and electrical conducting and magnetic properties of a radical cation salt of EDO-TTFVODS with magnetic FeCl4? ion, (EDO-TTFVODS)2FeCl4 (EDO-TTFVODS = ethylenedioxytetrathiafulvalenoquinone-1,3-diselenolemethide) are reported. In this salt, there are two independent donor molecules formed two different layers A and B, and the counter FeCl4? ions layer is sandwiched between two donor layers A and B along the b-axis. The donor molecules form the one-dimensional columns along the a-axis in both donor layers. This salt shows high conductivity at room temperature (σRT = 25 S cm?1) and a metallic behavior down to ca. 80 K, where a metal–insulator transition however occurs. The magnetic susceptibility obeys a Curie–Weiss law (Curie constant C = 4.42 emu K mol?1 and Weiss temperature Θ = ?1.5 K), without any magnetic ordering down to 1.8 K. This result suggests the weak antiferromagnetic interaction between the d spins of FeCl4? ions. 相似文献
99.
Cooking up an interactive olfactory game display. 总被引:2,自引:0,他引:2
Takamichi Nakamoto Shigeki Otaguro Masashi Kinoshita Masahiko Nagahama Keita Ohinishi Taro Ishida 《Computer Graphics and Applications, IEEE》2008,28(1):75-78
It's long been possible to give users outside an actual environment that environment's visual and auditory information and thus contribute to establishing presence. However, we've yet to establish much presence when users require olfactory information - such as in environments focused on foods, flowers, perfumes, or, in some cases, more offensive smells. Recently, several VR researchers have become interested in olfaction and olfactory displays that present smells in virtual environments (VEs). In this article, we describe our interactive olfactory display. One of our development goals is to confirm the assumption that users' interactions with the system increases presence. Thus, we used our interactive olfactory display to develop a cooking game in collaboration with electronic engineers and artists. 相似文献
100.
Takemoto A. Sakakibara Y. Nakajima Y. Fujiwara M. Kakimoto S. Namizaki H. Susaki W. 《Electronics letters》1987,23(11):546-547
A novel 1.3?m InGaAsP/lnP distributed-feedback buried-heterostructure laser diode on p-type InP substrate has been developed utilising a dopant diffusion technique. The laser has achieved a threshold current as low as 20 mA and high output power of 32 mW under CW and SLM operation. 相似文献