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991.
992.
Wen-Yao Chen Wen-Liang Hwang Tien-Ching Lin 《IEEE transactions on systems, man, and cybernetics. Part B, Cybernetics》2006,36(3):649-659
A prototype is representative of a set of similar objects. This paper proposes an approach that formulates the problem of prototype generation as finding the mean from a given set of objects, where the prototype solution must satisfy certain constraints. These constraints describe the important perceptual features of the sample shapes that the proposed prototype must retain. The contour prototype generated from a set of planar objects was used as an example of the approach, and the corners were used as the perceptual features to be preserved in the proposed prototype shape. However, finding a prototype solution for more than two contours is computationally intractable. A tree-based approach is therefore proposed in which an efficient greedy random algorithm is used to obtain a good approximation of the proposed prototype and analyze the expected complexity of the algorithm. The proposed prototype-generation process for hand-drawn patterns is described and discussed in this paper. 相似文献
993.
V. V. Tcherdyntsev S. D. Kaloshkin A. I. Salimon E. A. Leonova I. A. Tomilin J. Eckert F. Schurack V. D. Rogozin S. P. Pisarev Yu. P. Trykov 《Materials and Manufacturing Processes》2002,17(6):825-841
Al-Cu-Fe alloys were prepared from elemental powders in a high-energy planetary ball mill. A sequence of solid state reactions resulting in quasicrystal (QC) phase formation takes place during heating of the as-milled powder. These reactions were studied by both differential scanning calorimetry and x-ray diffraction methods. Mechanically alloyed powders were consolidated by cold and hot pressing, as well as by explosive compaction. After annealing at sufficiently high temperatures, the consolidated samples are single-phase QC, except the ones consolidated by explosion. The high reactivity of the as-milled alloys causes the appearance of high porosity of the consolidated samples after the annealing. 相似文献
994.
995.
996.
997.
Chai-Chin Lin Chih-Ming Chen Jenn-Hwan Tarng Hsueh-Ming Hang Hsiao-Cheng Yu 《Broadcasting, IEEE Transactions on》2002,48(1):38-43
Field tests of the transmission performance of the ATSC DTV system have been conducted in Taiwan. The test results as well as comparisons against the NTSC system performance are reported and analyzed. From the measured results the reception characteristics of the DTV can be deduced and can provide guidelines for television stations to design the transmission system, schedule equipment deployment, plan service coverage areas, and improve the reception quality of the digital signal 相似文献
998.
999.
A Dielectrophoretic Chip With a 3-D Electric Field Gradient 总被引:1,自引:0,他引:1
1000.
Preparation of nanocrystalline ZSM-5 has been proven possible with carbon matrix by using confined space synthesis. In combination with the hydrothermal method, by the use of a mesoporous carbon nanotube as the inert support material, ZSM-5 with SiO2/Al2O3 ratios of 100 was successfully synthesized with an average crystal size of 27 nm. Their structures were preliminarily characterized by x-ray power diffraction (XRPD) and infrared spectroscopy (IR), and scanning electron microscopy (SEM), respectively. At the same time, we put forward the mechanism about the confined space synthesis in terms of the results. 相似文献