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991.
992.
Phase-change read-and-write memory (PRAM) is a promising memory that can solve the problems of conventional memory—scalability, read/write speed, and reliability. We will review the opportunities and technical challenges of PRAM. The most important challenge of PRAM is the reduction of the writing current. Various approaches to reduce the writing current will be reviewed and the prospects of PRAM are discussed. 相似文献
993.
A. I. Ul'yanov É. F. Merzlyakov R. G. Faizullin 《Powder Metallurgy and Metal Ceramics》1995,33(1-2):61-63
Density and carbon content are studied for their effect on strength (hardness) and magnetic (coercive force, saturation magnetization) properties of powder steels ZhGr1 and ZhGr1D3. It is shown that the hardness of articles made of these steels may be determined indirectly by measuring two magnetic characteristics.Physicotechnical Institute, Russian Academy of Sciences, Izhevsk. Translated from Poroshkovaya Metallurgiya, Nos. 1–2, pp. 67–69, January–February, 1994. 相似文献
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995.
A digital AC voltage standard with well-known AC-to-DC output voltage difference is described. The proposed feedback configuration can effectively measure and correct for loading effects, caused by a measuring device. Because the AC standard can generate AC and DC voltages at the same output terminals, the automatic measuring setup for thermal voltage converters (TVC) is considerably simplified. The state-of-the-art stability of output voltage enables it to be used for intercomparison purposes 相似文献
996.
This work discusses the author suggestion for locating content in mixed-media for context-sensitive queries. Also provides examples of nontextual approach, a system for organizing digital photographs in which all of the instances of a particular person can be found based on face recognition rather than keyword matching, and compared with a conventional metadata effort that uses predictive labelling of objects in the base data set. 相似文献
997.
Multicolor optical solitons mediated by quadratic nonlinearities have been observed experimentally during the last few years in a variety of materials and geometries in a number of laboratories around the world. Today, many of the basic properties of the corresponding soliton families are theoretically well established. Nevertheless, experiments continuously reveal new surprises, and the topic is entering new theoretical and experimental territories. In this paper, we briefly outline the key features of the quadratic solitons and overview the latest developments. 相似文献
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