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901.
Shinichi Tamura Kokichi Tanaka Seiji Ohmori Kozo Okazaki Akira Okada Mitsuru Hoshi 《Pattern recognition》1983,16(2):149-162
An algorithm for measuring an index of leakage in fluorescein fundus angiography is presented. The number of pixels whose gray level exceeds an automatically determined slice level is calculated. An automatic blood vessel elimination technique is introduced. Further, a method of measuring the short term change of leakage from a time series of the fluorescein fundus angiographs is described. Our system can also deal with the time series images obtained on different occasions (long term change).The features of this paper are: (1) this paper deals with double time sequence images (short and long term); (2) an automatic blood vessel recognition algorithm is employed. 相似文献
902.
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904.
As a basic study of a Brillouin fiber-optic gyro, the state of polarization of stimulated Brillouin scattering in an optical fiber ring-resonator is analyzed. A high-birefringent fiber ring-resonator with 90° polarization axis rotation at the splice is considered as a candidate to have a stable lasing. It has two special states of polarization as the lasing modes, namely the polarization lateral modes. The lasing frequencies, namely the longitudinal modes for one state are fixed just in the middle point between the two neighboring lasing frequencies for the other in this resonator. This means that the stable single mode lasing may be obtained. The lasing threshold, the alternation of the lasing modes are discussed both by the simplified theory and the strict theory 相似文献
905.
Shigeru Imai Satoru Takagi Toshio Iizuka Osamu Sugiura Masakiyo Matsumura 《Materials and Manufacturing Processes》1995,10(2):267-281
Two methods are proposed and demonstrated successfully for low temperature atomic layer epitaxy (ALE) of Si, where H atoms play essential roles. The first method is the use of H as a self-limiting factor. Trisilane (Si3H8) was used as source gas and the substrate temperature was modulated in order to alternate steps in an ALE cycle. When the temperature was less than 380°C in the adsorption step and more than 520°C in the desorption step, respectively, the grown layer thickness per cycle was 0.8 ML/cycle. The second method is the use of atomic H as an active reducer of a self-limiting factor. A clean surface was exposed to dichlorosilane (SiH2Cl2) as source gas to grow an Si monolayer covered with CI. Next, atomic H was injected to reduce CI from the surface. An ideal monolayer growth was obtained with the substrate temperature over 540°C. 相似文献
906.
A. Takeoka S. Kouzuma H. Tanaka H. Inoue K. Murata M. Morizane N. Nakamura H. Nishiwaki M. Ohnishi S. Nakano Y. Kuwano 《Solar Energy Materials & Solar Cells》1993,29(3)
A new type of translucent amorphous silicon (a-Si) solar cell, called the see-through a-Si solar cell, is developed. It has multiple microscopic holes within its effective area to transmit light and it generates electric power. A series of technical data on the fabrication processing with various patterning and photovoltaic performance are presented. Some examples of application systems such as car sunroof and home interior are introduced and discussed on a wide variety of new areas of PV applications. The see-through a-Si solar cell was mounted on a car sunroof to drive the car's ventilating system or to charge its battery. The ventilating system reduced the interior temperature of the car from 61 to 47°C during daytime parking. 相似文献
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909.
This paper presents a new analytical modelling of suction cups used for window-cleaning robots. The modelling can be used when the force is parallel to the base surface of the suction cup. The basic idea of this analytical modelling is that the active area of suction cup will decrease as the air pressure decreases in the suction cup. The analytical modelling is based on the theory of elasticity. The results indicated that the suction force should be calculated by means of multiplying the air pressure by the active area of the suction cup rather than the bottom area that is commonly used in traditional methods, and that the friction between the suction cup and the surface of window glass could also be calculated. Finally, the results obtained by the analytical modelling were verified and compared with those calculated by the traditional method. 相似文献
910.