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排序方式: 共有409条查询结果,搜索用时 31 毫秒
141.
Haruo Ihori Kotaro Tanino Takao Kawasaki Masaharu Fujii Kiyomitsu Arii 《Electrical Engineering in Japan》2002,139(1):9-15
We have already reported on reconstructions of the symmetrical and nonsymmetrical electric field vector distribution using the Kerr electrooptic effect and our unique reconstruction method, a modified computed tomography technique. This reconstruction technique gives an electric field map, that is, the strength and the direction of the electric field vector, on any plane. For the reconstruction of one field vector distribution, it was necessary to measure the light intensity twice while changing the optical axis of optical wedges. Moreover, the intensity measurement must be carried out at many points around the electrode system. Therefore, considerable time was required to measure the electric field distribution. We therefore developed a simultaneous three‐direction optical measurement system with three optical systems combined with the two‐beam method. Using the new measurement system, we measured the electric field distribution on planes in a sphere‐to‐sphere electrode system. It took about 0.1 second to measure the light intensity data for the reconstruction. © 2002 Scripta Technica, Electr Eng Jpn, 139(1): 9–15, 2002; DOI 10.1002/eej.1141 相似文献
142.
Hirasawa S. Watanabe T. Takagaki T. Uchino T. 《Semiconductor Manufacturing, IEEE Transactions on》1994,7(4):423-429
Transient temperature distribution was calculated for wafers heated in a new hot-wall-type rapid diffusion furnace. Two-dimensional radiative heat transfer was combined with unsteady conduction in wafers and the furnace. The furnace is composed of parallel plate heaters, and heats wafers to a temperature of about 1000°C. The heaters are divided into four zones and their heating powers are PID-controlled. Two wafers on a holder are inserted vertically from the bottom of the furnace, and heated for three minutes. The calculated results show the wafer temperature approached the desired heating temperature about one minute after insertion, agreeing with experimental results. The average temperature distribution in the wafers during heating is found to be within ±1°C at 1000°C, when the heating power (temperature) of the four zones is properly controlled. The effects of heater temperature, insertion speed, and holder thickness on the temperature distribution in wafers were calculated. The new hot-wall-type rapid diffusion furnace can be used to manufacture future VLSI 相似文献
143.
144.
Kotaro Takahama Hiroaki Sobagaki Yoshinobu Nayatani 《Color research and application》1984,9(2):106-115
The nonlinear model of chromatic adaptation of Nayatani, Takahama, and Sobagaki1–3 is extended to apply to an adapting field with a light-gray background. Its formulation and computational procedure are described in detail. Using the extended formulation, the following adaptation effects are predicted for a background reflectance of 50%: )1( the chromatic-adaptation effect between standard illuminants D65 and A, )2( the change of colorfulness of colored samples )the Hunt effect(, )3( the change of bright and dark contrast of nonselective samples )the Stevens effect(, and )4( the color perception of nonselective samples under a colored adapting illumination )the Helson-Judd effect(. Effects )2( and )3( are observed by changing the adapting luminance. The effect of changing the background reflectance from 0.20 to 0.50 is discussed with respect to prediction of the above four effects. This change is especially significant in the Helson-Judd effect but less so in the others. 相似文献
145.
The activity of arginine decarboxylase (ADC) in leaves of Pharbitis nil was induced by light. The ADC activity increased to a maximum 1 h after illumination, followed by a gradual decrease. This suggested light either induced synthesis of ADC protein de novo or was involved in its activation. Cycloheximide inhibited the photoinduction of ADC activity, and the half life of ADC in leaves was 30-40 min. The temperature and relative humidity in darkness before illumination had no effect on the photoinduction of ADC activity, contrary to the photoresponse of S-adenosylmethionine decarboxylase (SAMDC) activity where the conditions of darkness before lights-on have a marked effect. The light response of the polyamine (PA)-biosynthetic enzyme activity produced transient accumulation of PA. The level of spermidine increased in leaves in which activities of both SAMDC and ADC increased after illumination, while the level of putrescine increased in leaves in which the activity of ADC increased but that of SAMDC did not. 相似文献
146.
147.
Hirasawa K. Ohbayashi M. Sakai S. Jinglu Hu 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》1998,28(6):781-789
According to recent knowledge of brain science it is suggested that there exists functions distribution, which means that specific parts exist in the brain for realizing specific functions. This paper introduces a new brain-like model called Learning Petri Network (LPN) that has the capability of functions distribution and learning. The idea is to use Petri net to realize the functions distribution and to incorporate the learning and representing ability of neural network into the Petri net. The obtained LPN can be used in the same way as a neural network to model and control dynamic systems, while it is distinctive to a neural network in that it has the capability of functions distribution. An application of the LPN to nonlinear crane control systems is discussed. It is shown via numerical simulations that the proposed LPN controller has superior performance to the commonly-used neural network one. 相似文献
148.
Morishita H. Hirasawa K. Fujimoto K. 《Antennas and Propagation, IEEE Transactions on》1991,39(10):1472-1478
Analysis of a cavity-backed annular slot antenna with one point shorted is performed experimentally and theoretically. Resonance frequencies, bandwidths, and radiation patterns are studied with respect to slot width, cavity depth, and slot shorting position. In the theoretical analysis, the method of moments is applied to find the magnet current on the slot, and the Green's function for the field inside the cavity has been newly derived. By selecting a slot shorting position, circular polarization, and a bandwidth of more than 10%, the voltage standing-wave ratio (VSWR) ⩽2 for the input impedance is obtained 相似文献
149.
A nitrosyliron(II) complex with EDTA was produced by reaction of the Fe(II)—EDTA complex and nitrous acid in citric acid—phosphate buffer solution. The experimental results pointed out that nitrous acid is reduced to nitrous oxide by Fe(II)—EDTA complex followed by the formation reaction of nitrosyliron(II) EDTA complex. The composition of this complex was determined to be Fe(II) (NO)2EDTA by both electrochemical and spectroscopic methods.A mechanism of the oxidation of Fe(II) (NO)2EDTA was proposed in which nitrous oxide breaks away from the iron ion. The photoeffect on this reaction is discussed. 相似文献
150.
The method of singular-value decomposition analysis of matrices is used to analyze the 20 color-matching functions of Stiles's observers. It is confirmed that the 20 color-matching functions are well reconstituted by the first three decomposed components. A new deviate observer is derived from the first decomposed component. It is shown that the new deviate observer can be used well in the computation of observer-metamerism indices. Furthermore, an optimized deviate observer is developed by modifying the color-matching functions of the new deviate observer slightly. Both the new and the optimized deviate observer give a basis for the further study of the evaluation of observer metamerism. 相似文献