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991.
992.
V. A. Borodulya V. L. Ganzha Yu. S. Teplitskii Yu. G. Epanov 《Journal of Engineering Physics and Thermophysics》1985,49(4):1197-1202
We propose a simplified model of external heat transfer in a fluidized bed. We compare calculated and experimental data, and recommend a computational procedure in polydisperse beds.Translated from Inzhenerno-Fizicheskii Zhurnal, Vol. 49, No. 4, pp. 621–626, October, 1985. 相似文献
993.
Lawrence E. Holloway Yu Gong Jeff Ashley 《Mathematics and computers in simulation》2006,70(5-6):275-286
This paper introduces the concepts of state observability and condition observability for condition systems, a class of systems composed of discrete state components which interact via discrete binary signals called conditions. Given a set of externally observed conditions, state observability implies that the state of the system can be determined from the observations, and condition observability implies that all unobserved input and output conditions of the system can be determined from the observations. In this paper, we present a class of systems which is state observable and condition observable. We present a method to synthesize an observer system to provide state and condition signal estimates for a single component subsystem. 相似文献
994.
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997.
Yu. G. Vasin A. D. Krakhnov T. Sh. Utesheva 《Pattern Recognition and Image Analysis》2006,16(1):104-105
The development of efficient techniques for converting information obtained from complicated graphical documents into a digital
form is considered. It is shown that the use of discrete geometry methods make it possible to improve the efficiency of many
technological stages.
The work was supported by the Russian Foundation for Basic Research, project no. 00-15-96018 and by the Integration Foundation,
project no. K-03392. 相似文献
998.
An approach to the calculation and design of metal forming is proposed and theoretically considered. This approach can minimize the nonuniformity of a deformation distribution over the cross section of ready products, which is equal to controlling the structure and properties of forged pieces. This approach is based on the calculation of the intermediate shapes of a forged piece by solving a set of inverse forming problems using the boundary element method and by constructing a forging process that is optimal according to a given criterion using dynamic programming. 相似文献
999.
M. Yu. Kollerov A. A. Ilyin I. S. Pol’kin A. S. Fainbron D. E. Gusev S. V. Khachin 《Russian Metallurgy (Metally)》2007,(5):408-414
The effects of the charge composition, casting method, and metal forming method on the structure and shape-memory-effect (SME) and superelasticity characteristics of titanium nickelide-based alloys are studied. The shape recovery temperatures of semiproducts are shown to depend substantially on the volume fraction of the Ti2Ni intermetallic phase, whose formation is stimulated by the oxygen present in a charge or absorbed during casting. An increase in the volume fraction of Ti2Ni in an alloy leads to nickel enrichment of the B2 phase and a decrease in the shape recovery temperatures. Subsequent metal forming at the stage of semiproduct manufacture only weakly affects the volume fraction of Ti2Ni and favors the formation of its equiaxed shape and a more uniform Ti2Ni distribution in the B2 matrix. In alloys where the B2 phase contains more than 56.5 wt % Ni, quenching from temperatures above 600°C and aging in the temperature range 400–500°C result in the dissolution and precipitation, respectively, of the nickel-rich Ti3Ni4 and Ti2Ni3 intermetallics. Therefore, the shape recovery temperatures of semiproducts and finished products can be controlled. Moreover, as the aging temperature changes, the volume fraction and size of nickel-rich intermetallic particles, the slip stresses, and the SME force characteristics change. For example, to increase the compression forces for osteosynthesis fixation devices, one has to use a titanium nickelide-based alloy with a high nickel content in the B2 phase and to perform aging at low temperatures (400–450°C). 相似文献
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