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981.
One considers the differential equation dx/dt=f(t, x) with the impulse action ¦t=ti=Hi(ti,x) in the space of bounded numerical sequences, where f(t, x), Hi(t, x) are T-periodic, countable-dimensional vector-valued functions, is a positive parameter. One gives conditions for the existence of a control (1,2) such that the solution of the equation dx/dt=f(t, x)–1 with impulse action x¦t=ti=Hi(ti,x)–2 assuming for t= the value x=x0, be T-periodic.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 2, pp. 271–275, February, 1990. 相似文献
982.
The problem of estimating the rate of convergence in the central limit theorem for the U-statistics with values in the Hilbert space is considered. Bounds of the order o(n–1/2) if the kernel satisfies the nondegenerate condition and E3 < .Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 8, pp. 1043–1050, August, 1990. 相似文献
983.
Yu. I. Volkov 《Ukrainian Mathematical Journal》1990,42(7):785-796
The concept of the deformation of positive linear operators of type B is introduced, in particular, that of a linear deformation of operators. These concepts are applied to the solving of operator equations of type B. One solves completely the problems of the determination of all positive linear operators of type B for which the covariance of the operators is 1) a polynomial of degrees 3; 2) any power function; 3) an exponential function. In addition, one finds; two families of positive linear operators of type B for which the covariance is a polynomial of degree four.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 42, No. 7, pp. 888–900, July, 1990. 相似文献
984.
V. M. Akhundov 《Mechanics of Composite Materials》1990,26(1):97-104
Conclusion An iterative method was proposed for numerical solution of problems concerning the axisymmetric deformation of uniform and laminated shells of revolution made of highly elastic materials. Calculations performed for rubber, rubber-fiber, and rubber-layered shells demonstrate the reliability and effectiveness of the method.Translated from Mekhanika Kompozitnykh Materialov, No. 1, pp. 109–116, January–February, 1990. 相似文献
985.
We give a brief overview of important results in several areas of sensitivity and stability analysis for nonlinear programming, focusing initially on qualitative characterizations (e.g., continuity, differentiability and convexity) of the optimal value function. Subsequent results concern quantitative measures, in particular optimal value and solution point parameter derivative calculations, algorithmic approximations, and bounds. Our treatment is far from exhaustive and concentrates on results that hold for smooth well-structured problems.Research supported by National Science Foundation Grant ECS-86-19859 and Grant N00014-89-J-1537 Office of Naval Research. 相似文献
986.
Anthony V. Fiacco 《Annals of Operations Research》1990,27(1):371-380
Penalty function techniques are well known perturbation methods for solving mathematical programming problems. We define new classes of penalty functions by introducing simple perturbations of classical penalty functions or, equivalently, perturbations of the given problem. Motivation is a recently developed method called Projective SUMT, proposed by McCormick, based on solving the differential equation associated with a barrier function minimizing trajectory. We show that this trajectory-following algorithm is a simple variation of classical SUMT (Sequential Unconstrained Minimization Technique). This leads to numerous additional interpretations, simplified convergence results, duality relationships and extensions. Like SUMT, Projective SUMT is closely related to the approach of Karmarkar.Research supported by Grant ECS-86195859 and NSF N00014-85-K-0052, Office of Naval Research. 相似文献
987.
A. V. Zorin 《Russian Physics Journal》1990,33(5):441-443
A general form of chronological ordering is proposed, based on introduction of relativistically invariant multipoint step functions (x1, ..., xn). A system of recursive relations is established for these functions, which guarantees that the scattering matrix is unitary, covariant, and causal. The explicit form of the first four -functions is found. A comparative analysis of the known methods of chronological ordering is given.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 5, pp. 70–73, May, 1990. 相似文献
988.
The simplest gauge theory of an elastic-plastic medium is considered in this paper that takes account of just translational plasticity. The equations of motion for such a model turn out to be linear and permit the normal modes spectrum of a medium to be obtained. Taking account of plasticity results in a cardinal transformation of the elastic branches of the spectrum and the appearance of a group of plasma oscillations of a dislocation gas.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 6, pp. 64–68, June, 1990. 相似文献
989.
The problem for a one-temperature plasma is considered with allowance for the finite ionization rate. It is shown that in the developed nonequilibrium case the leading effect of ambipolar electron diffusion and ionization lag lead to a qualitatively different picture as compared with the equilibrium case. In particular, the heat release zone covers only a relatively small leading part of the ionization zone with a relatively low (ne nef) electron concentration.Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 3, pp. 161–169, May–June, 1989.The authors thank A. A. Barmin and A. G. Kulikovskii for useful discussions. 相似文献
990.
Impossibility of centrally symmetric shock waves in vacuum in the relativistic theory of gravitation
A. V. Genk 《Theoretical and Mathematical Physics》1989,79(3):665-670
Burevestnik Scientific-Industrial Union, Leningrad. Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 79, No. 3, pp. 473–480, June, 1989. 相似文献