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991.
Institute of Rock Mechanics, Academy of Sciences of the USSR, Moscow. Translated from Fiziko-Tekhnicheskie Problemy Razrabotki Poleznykh Iskopaemykh, No. 1, pp. 39–44, January-February, 1992.  相似文献   
992.
The influence of the structure and crystallographic texture of VT3-1 alloy formed by thermomechanical processing of a forging and also of the production factors of subsequent production of a gas turbine engine blade from the forging on the fatigue resistance characteristics was investigated. It was established that the reason for the reduction in fatigue limit and the significant spread in test data is nonuniformity of the structure and texture, both in different forgings and within the same forging, caused by variations in such parameters of thermomechanical processing as the temperature and degree of deformation. The nonuniformity plays a determining role in the reduction in fatigue limit as the result of hydrogen absorption during chemical etching. It was shown that such an effect may be eliminated by degassing vacuum annealing and the general level of fatigue resistance characteristics may be increased as the result of thermomechanical processing of forgings with strict observance of the specified forging temperature.Translated from Problemy Prochnosti, No. 6, pp. 12–19, June, 1992.  相似文献   
993.
994.
Translated from Khimicheskoe i Neftyanoe Mashinostroenie, No. 4, pp. 32–33, April, 1991.  相似文献   
995.
996.
Academic Science Complex, A. V. Lykov Institute of Heat and Mass Transfer, Academy of Sciences, Belorussia, Minsk. Translated from Inzhenerno-fizicheskii Zhurnal, Vol. 62, No. 1, pp. 95–101, January, 1992.  相似文献   
997.
998.
In this paper, the scattering of electromagnetic waves by a perfectly conducting semi-infinite elliptic cone is treated. The exact solution of this boundary value problem in problem-adapted spheroconal coordinates in the form of a spherical multipole expansion is of poor convergence if both the source point and the field point are far away from the cone's tip. Therefore, an appropriate sequence transformation of these series expansions (we apply the Shanks transformation) is necessary to numerically determine the dyadic diffraction coefficients and bistatic radar cross sections (RCS) for an arbitrary elliptic cone. Our far-field data for an elliptic cone, a circular cone, and a plane angular sector are compared with some other results obtained with the aid of quite different methods  相似文献   
999.
The results of a study of photoluminescence excited by a nitrogen laser in the space charge region of Ni-ZnSe contacts are presented. It is found that the photoluminescence intensity is modulated not only in the presence of an external voltage but also in its absence, and that it depends on the diode switching regime: no load or short circuit. A physical interpretation of the results is given. Fiz. Tekh. Poluprovodn. 32, 1210–1212 (October 1998)  相似文献   
1000.
There is ample evidence that people cannot generate random series when instructed to do so. Rather, they produce sequences with too few symmetries and long runs and too many alternations among events. The authors propose a psychological theory to account for these findings, which assumes that subjects generate nonrandom sequences that locally represent theoretical random series subject to a constraint on their short-term memory. Closed-form expressions are then derived for the major statistics that have been used to test for deviations from randomness. Results from 3 experiments with 2 and 3 equiprobable alternatives support the model on both the individual and group levels. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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