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101.
Koh Matsumoto Kazutada Ikenaga Jun Yamamoto Kazuki Naito Yoshiki Yano Akinori Ubukata Hiroki Tokunaga Tadanobu Arimura Katsuaki Cho Toshiya Tabuchi Akira Yamaguchi Yasuhiro Harada Yuzaburo Ban Kousuke Uchiyama 《半导体学报》2011,32(1):21-23
Growth rate has a direct impact on the productivity of nitride LED production.Atmospheric pressure growth of GaN with a growth rate as high as 10μm/h and also Al0.1Ga0.9N growth of 1μm/h by using 4 inch by 11 production scale MOVPE are described.XRD of(002) and(102) direction was 200 arcsec and 250 arcsec, respectively.Impact of the growth rate on productivity is discussed. 相似文献
102.
Hironao Ogura Hiroki Ishida Ryuta Yokooji Hiroyuki Kage Yoshizo Matsuno Arun S. Mujumdar 《Drying Technology》2001,19(7):1461-1477
The authors have been studying Chemical Heat Pumps (CHP) from the viewpoints of energy saving and environmental impact. The CHP can store thermal energy in the form of chemical energy by an endothermic reaction, and release it at various temperature levels during heat demand periods by exo/endothermic reactions. The authors have proposed in an earlier study a novel chemical heat pump (CHP) system for environmentally-friendly effective utilization of thermal energy in drying as a chemical heat pump dryer (CHPD). In this exploratory study, we test the effectiveness of operating the proposed CHPDs experimentally. Basic experiments on the CHPDs such as hot dry air production for convective drying are performed on lab-scale CHPD apparatuses using gas-solid reactions in calcium oxide/calcium hydroxide reactant beds. The proposed CHPDs are found to produce hot air by CHP operation for drying. The temperature levels of the produced hot air and the reaction rates/conversions are as good as in the case of hot water supply system using basically same CHP operation. The cold heat for air dehumidification is also found to be generated/recovered by the same CHPD system. The generated heat amounts can be increased by changing the operating conditions although the heat recovery must be enhanced for practical application of CHPDs. 相似文献
103.
Ito M. Nitta K. Ohno K. Saigusa M. Nishida M. Yoshioka S. Irita T. Koike T. Kamei T. Komuro T. Hattori T. Arai Y. Kodama Y. 《Solid-State Circuits, IEEE Journal of》2009,44(1):83-89
Supporting both WCDMA with HSDPA and GSM/GPRS/EDGE, the 9.3 times 9.3 mm2 SoC fabricated in triple-Vth 65 nm CMOS, has three CPU cores and 20 separate power domains. Unused power domains can be powered down to reduce the leakage power. Partial clock activation scheme especially focused on music playback scene dynamically stops a PLL and clock trees when not necessary and reduces power consumption from 33.6 mW to 19.6 mW. IP-MMU translates virtual address to physical address for 18 hardware-IPs and virtual address space can be allocated when necessary and can be freed after its operation, reducing external memory by 43 MB. Video performance of D1 (720 times 520) size with 30 frames per second for MPEG/AVC decoding and encoding can be achieved under mixed virtual and physical address usage. 相似文献
104.
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106.
Zhu Y. Otsubo M. Honda C. Hashimoto Y. Ohno A. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2005,12(3):556-565
This paper describes the results of experiments and simulations made to examine the waveform of leakage current flowing through the surface of HTV (high temperature vulcanized) silicone rubber specimen exposed to clean fog. Water droplets were placed on the surface of specimen energized with AC voltage and investigations of the surface state were done by a high-speed video camera in a wet condition produced by sprayed clean fog. Simultaneously, according to the experimental condition, a dynamic 3-D model was built to calculate the electric field and current density distribution on the specimen surface by a finite element software. A conducting water layer is formed due to the deformation of droplets and the development of dry band arcing. This caused large distortion and nonlinearly which increased the odd harmonic components in the leakage current waveform. This is in good agreement with the simulating calculation. The information from the leakage current frequency characteristic was extracted and correlated with the insulation surface condition. It can be considered as a diagnostic index for electrical characteristics and insulation state of polymer insulators in the wet condition. 相似文献
107.
Kameda Atsushi Yamamoto Masahito Uejima Hiroki Hagiya Masami Sakamoto Kensaku Ohuchi Azuma 《Natural computing》2005,4(2):103-126
In this paper, we propose a new architecture for a multi-state DNA machine whose conformation of repeated hairpin structures changes sequentially in response to input oligomers. As an application of the machine, we also propose molecular memory in which the machine is used as a memory unit. Addressing in the memory is realized through state transitions of the machine. We then describe a method for designing DNA sequences of the machine, which exhaustively checks conformational changes of the machine by dividing its secondary structure into hairpin units. The method is based on the minimum free energy of the structure, the structure transition paths, and the total frequency of optimal and suboptimal structures. DNA sequences designed by the method were tested in a chemical experiment in which a machine consisting of two hairpins was actually constructed. As a result, we verified that the multi-state DNA machine realized the expected changes in its secondary structure. 相似文献
108.
This paper discusses robust seeking control of hard disk drives by the use of a variable structure multi-rate estimator (VSME). Compensation of pivot nonlinearity is one concern in the design of the seeking control, systems. Pivot nonlinearity is subject to uncertainties, and is difficult to deal with by a linear controller. The VSME estimates a class of uncertain disturbances and nonlinearities and yields compensation current through the linear feedback gain, which reduces the residual vibration and error during settling. Several experiments were carried out on several drives including a 3.5 in. 7,200 rpm drive. These experiments confirmed that the off-track probability after settling, which is defined by the number of seek failures over all trials, is much reduced to less than 1% when the drive is operated under a special temperature condition that increases pivot nonlinearity while the corresponding performance of a conventional linear controller is 12%. The seek failure is defined as the case when the position cannot be maintained within ±2.5% of a track pitch for a certain duration after track seeking mode. 相似文献
109.
Mitsutoshi Miyasaka Hiroyuki Hara Hiroki Takao Simon Tam Rob Payne Prem Rajalingham Satoshi Inoue Tatsuya Shimoda 《Journal of the Society for Information Display》2005,13(3):187-191
Abstract— Thin‐film transistors (TFTs) are field‐effect transistors that can be used to create large‐scale‐integrated (LSI) circuits. The combination of high‐performance TFTs and transfer technology of the TFTs has the potential to foster the rise of a new flexible microelectronics industry. This paper discusses the current status of flexible microelectronics, using a TFT fingerprint sensor (FPS) as an example. Technology used in active‐matrix displays can easily be applied to the TFT FPS. TFT technology should not be confined to the display industry; its use should be expanded into the semiconductor industry. With the result presented in this paper, we declare a new era of flexible microelectronics open. 相似文献
110.