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851.
852.
853.
The Z0-boson contribution to the elastic scattering amplitude of an electron in an arbitrary plane-wave electromagnetic field is obtained. Special cases of the plane-wave field are considered.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Fizika, No. 2, pp. 33–39, February, 1991. 相似文献
854.
855.
We obtain equations that describe heat conduction of bodies spatially reinforced by a system of capillary tubes filled with a moving heat-tapping fluid. The corresponding initial boundary-value problem of heat conduction is formulated and qualitatively analyzed. For thin-walled structures, we present an algorithm for reduction of the three-dimensional problem to a two-dimensional one. Specific calculations in solving the formulated problem are performed in the stationary and axisymmetric cases for a conic shell of revolution. The influence of the reinforcement parameters (intensity and direction), velocity of fluid motion in thermal tubes, dimensions of the inner sections of the tubes, and cone angle of a shell on the temperature field is investigated. 相似文献
856.
857.
Limit theorems for the logarithm of the likelihood ratio are proven. With their help the rate of decrease in the probability of errors of the second kind in the Neumann-Pierson criterion is established.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 44, No. 10, pp. 1382–1388, October, 1992. 相似文献
858.
We study applications of asymptotic methods of nonlinear mechanics and the method of Fokker-Planck-Kolmogorov equations to
stochastic oscillations in quasilinear oscillating systems with random perturbations.
__________
Translated from Neliniini Kolyvannya, Vol. 10, No. 4, pp. 510–518, October–December, 2007. 相似文献
859.
Yifeng Yu 《纯数学与应用数学通讯》2007,60(8):1111-1147
In the first part of this paper, we extend several results in Crandall, Evans, and Gariepy [11] and Crandall and Evans [10] to absolute minimizers of more general L∞ functionals. In the second part, we present some interesting connections between L∞ variational problems and weak KAM theory. As an application, we will advance the main result in Fathi and Siconolfi [17], i.e, the existence of a C1 subsolution of the Hamilton‐Jacobi equation. Moreover, we will propose a possible approximation of the projected Aubrey set by a variational approach that was first used by Evans in [14]. © 2007 Wiley Periodicals, Inc. 相似文献
860.
C.X. Gao F.C. Yu S.Y. Jeong A.R. Choi P. Parchinskiy D.J. Kim H.J. Kim Y.E. Ihm C.G. Kim C.S. Kim 《Journal of magnetism and magnetic materials》2006
GaMnN and Be-codoped GaMnN were grown via molecular beam epitaxy using a single GaN precursor and their structural and magnetic properties were examined. X-ray diffraction and superconducting quantum interference device (SQUID) measurements revealed that the grown layers are homogeneous without precipitates. The saturation magnetization of GaMnN has increased from ∼4 to ∼16 emu/cm3 via codoping of Be. The d–d exchange interaction between Mn atoms was discussed for the ferromagnetism of GaMnN. 相似文献