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排序方式: 共有107条查询结果,搜索用时 390 毫秒
1.
2.
A model is given and a periodic boundary condition is adopted to analyze magnetic fields of a delta type shunt reactor. An approximate three-dimensional finite-element method that combines some axisymmetric fields and a two-dimensional field is then applied. It is found that the flux in the yoke concentrates on the part that is near the legs. The flux density heightens as the legs is approached, and rotational magnetic flux occurs in the parts joined by a leg and the yoke. All flux density waveforms contain mainly third harmonics. It is found that there is rotating flux in the yoke, which causes increased core losses 相似文献
3.
Masahiro Fujimoto Mamoru Ishida Akihiko Fujii Yoshimine Sakamoto Norifumi Fujita Seiji Shinkai Masanori Ozaki 《Synthetic Metals》2009,159(9-10):871-874
The molecular alignment of polydiacetylene (PDA) derivatives and their optical and electrical properties of thin films based on PDA derivatives have been studied. The PDA derivatives were aligned depending on the direction of applied shear stress in the film. From measurements of the polarized absorption and current–voltage characteristics, the optical and electrical anisotropies have been observed, that was discussed by taking the PDA main chain alignment into consideration. 相似文献
4.
Shikano H. Ito M. Onouchi M. Todaka T. Tsunoda T. Kodama T. Uchiyama K. Odaka T. Kamei T. Nagahama E. Kusaoke M. Nitta Y. Wada Y. Kimura K. Kasahara H. 《Solid-State Circuits, IEEE Journal of》2008,43(4):902-910
This paper describes a heterogeneous multi-core processor (HMCP) architecture that integrates general-purpose processors (CPUs) and accelerators (ACCs) to achieve exceptional performance as well as low-power consumption for the SoCs of embedded systems. The memory architectures of CPUs and ACCs were unified to improve programming and compiling efficiency. Advanced audio codec-low complexity (AAC-LC) stereo audio encoding was parallelized on a heterogeneous multi-core having homogeneous processor cores and dynamically reconfigurable processor (DRP) ACC cores in a preliminary evaluation of the HMCP architecture. The performance evaluation revealed that 54times AAC encoding was achieved on the chip with two CPUs at 600 MHz and two DRPs at 300 MHz, which achieved encoding of an entire CD within 1- 2 min. 相似文献
5.
Cryogenic slush fluids such as slush hydrogen and slush nitrogen are two-phase, single-component fluids containing solid particles in a liquid. Since their density and refrigerant capacity are greater than those of liquid-state fluid alone, there are high expectations for the use of slush fluids in various applications such as clean-energy fuels, spacecraft fuels for improved efficiency in transportation and storage, and as refrigerants for high-temperature superconducting equipment. Experimental tests were performed using slush nitrogen to obtain the flow and heat-transfer characteristics in two different types of horizontal circular pipes with inner diameters of 10 and 15 mm. One of the primary objectives for the study was to investigate the effect of pipe diameter on the pressure-drop reduction and heat-transfer deterioration of slush nitrogen according to changes in the pipe flow velocity, solid fraction and heat flux. In the case of an inner diameter of 15 mm, pressure drop was reduced and heat-transfer characteristics deteriorated when the pipe flow velocity was higher than 3.6 m/s. On the other hand, in the case of an inner diameter of 10 mm, pressure drop was reduced and heat-transfer characteristics deteriorated when the pipe flow velocity was higher than 2.0 m/s. From these results, it can be seen that a larger pipe diameter produces a higher onset velocity for reducing pressure drop and deteriorating heat-transfer characteristics. Furthermore, based on observations using a high-speed video camera, it was confirmed that pressure drop was reduced and heat-transfer characteristics deteriorated when the solid particles migrated to the center of the pipe and the flow pattern of the solid particles inside the pipe was pseudo-homogeneous. 相似文献
6.
Synthesis of non-equilibrium phases in immiscible metals mechanically mixed by high pressure torsion
Tatsuya Miyazaki Daisuke Terada Yoji Miyajima Challapalli Suryanarayana Reiko Murao Yoshihiko Yokoyama Kazumasa Sugiyama Minoru Umemoto Yoshikazu Todaka Nobuhiro Tsuji 《Journal of Materials Science》2011,46(12):4296-4301
The structural changes in mechanically mixed metals of immiscible combinations of elements caused by bulk mechanical alloying
(MA) through the use of high pressure torsion (HPT) were investigated in Ag–Ni and Nb–Zr systems. There was no alloying between
Ag and Ni on atomic scale even after 100 rotations of HPT. On the other hand, the β-Zr phase started to appear after HPT 2
rotations in the Nb–Zr system, even though β-Zr is a high temperature phase. Further, Nb and Zr were completely mixed to form
a bcc structured single phase after HPT 100 rotations. The sequence of alloying in the Nb–Zr system during HPT was discussed.
These results clearly suggest that non-equilibrium phases can form in the Nb–Zr system by bulk MA by the use of HPT. 相似文献
7.
H Kodama Y Kodama S Shinozawa R Kanemaru K Todaka Y Mitsuyama 《Canadian Metallurgical Quarterly》1998,23(5):361-365
Recently a German appraisal instrument for clinical guidelines was published that could be used by various parties in formal evaluation of guidelines. An user's guide to the appraisal instrument was designed that contains a detailed explanation for each question to ensure that the instrument is interpreted consistently. This paper describes the purposes, format and contents of the user's guide, and reviews the key factors influencing the validity of guidelines. Taking into account international experiences, the purposes, chances and methodological limitations of a prospective assessment of clinical practice guidelines are discussed. 相似文献
8.
The numerical implementation of the boundary-element method formulated for 3-D eddy-current problems is presented. In particular, the algorithm for solving these problems, together with the formulation for the magnetic vector potential and the electric potential using the Lorentz gauge, is discussed in detail. Based on accurate calculations of the numerical solution at interior points in the neighborhood of the boundary, the revised integration method shown earlier by the authors (1988) is extended to this 3-D magnetic field analysis for the steady-state 相似文献
9.
Norifumi Shirasaka Sakayu Shimizu 《Journal of the American Oil Chemists' Society》1995,72(12):1545-1549
Saprolegnia sp. 28YTF-1, isolated from a freshwater sample, is a potent producer of 5,8,11,14,17-cis-eicosapentaenoic acid (EPA). The fungus used various kinds of carbon sources, such as starch, dextrin, sucrose, glucose,
and olive oil for growth, and olive oil was the best carbon source for EPA production. The EPA content reached 17 mg/g dry
mycelium (0.25 mg/L) when the fungus was grown in a medium that contained 2.5% olive oil and 0.5% yeast extract, at pH 6.0
and 28°C for 6 d with shaking. Accompanying production of arachidonic acid (AA; 3.2 mg/g dry mycelia, EPA/AA = 5.1) and other
ω6 polyunsaturated fatty acids was low. Both EPA content and EPA/AA ratio increased in parallel by lowering growth temperature.
Triglyceride was the major mycelial lipid (ca. 84%), but EPA comprised only 2.2% of the total fatty acids of this lipid. About 40% of the EPA produced was found in polar
lipids, such as phosphatidylethanolamine (EPA content, 28.2%), phosphatidylcholine (13.6%), and phosphatidylserine (21.2%). 相似文献
10.
Xingyang?Wu Norifumi?Kobayashi Hidetaka?Nanao Shigeyuki?MoriEmail author 《Tribology Letters》2005,18(2):239-244
Adsorption and reaction of cyclohexene, 1-hexene and benzene on nascent gold surface formed by friction were investigated using an adsorption test apparatus in high vacuum at room temperature. Chemisorption of cyclohexene, 1-hexene and benzene was observed during the sliding processes by a quadrupole mass spectrometer. It is found that nascent gold surface has catalytic activity for hydrogenation of cyclohexene and 1-hexene, and for dehydrogenation of the olefins and benzene. The adsorbed cyclohexene and 1-hexene molecules were hydrogenated on the surface to form cyclohexane and hexane, respectively. As dehydrogenation products, hydrogen from all the sample gases, and benzene from cyclohexene desorbed. Adsorption rate of the olefins was higher than that of benzene, and hydrogenation activity of 1-hexene is higher than that of cyclohexene. However, on nascent Pd–Ag alloy surface, the desorption of hydrogenation products was not detected, although adsorption of the sample gases and desorption of the dehydrogenation products were also observed. 相似文献