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991.
It is found that, in the spherical coordinate system, the fundamental solution of the Helmholtz equation in a wedge satisfies the Sommerfeld radiation conditions at infinity uniformly in angle coordinates.Deceased.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 9, pp. 1312–1314, September, 1993. 相似文献
992.
Vogel N. Heinzinger J. Cichos F. 《IEEE transactions on plasma science. IEEE Nuclear and Plasma Sciences Society》1995,23(6):926-931
The cathode spot formation in air within the first 170 ns was investigated by laser absorption photography and ps-pulse interferometry. The discharge was initiated between electrodes made from Ag or Pd with cathode-anode distance below 300 μm, the arc duration was some milliseconds, and the arc current 5-10 A. Picosecond holographic interferometry and momentary absorption photography yielded spatial-temporal density distributions in the ignition phase of the cathode spot. An absolute electron density value on the order of 4×1026 m-3 has been found. In contrast to vacuum, the cathode spot plasmas broaden little with increasing distance from the cathode, thus narrow plasma channels are observed in the vicinity of the cathode surface having diameters <20 μm 相似文献
993.
The quantum defect orbital (QDO ) method and its relativistic (RQDO ) counterpart have been employed in this work to compute oscillator strengths for several fine-structure transitions in members of the copper isoelectronic sequence up to Z = 92. The RQDO results are found to be in quite good agreement with the best estimates derived from other sources, whenever the comparison is possible. © 1994 John Wiley & Sons, Inc. 相似文献
994.
995.
G.N. Gatica 《Applied Mathematics Letters》1997,10(6):29-35
We study the solvability and Galerkin approximation of an exterior hyperelastic interface problem arising in plane elasticity. The weak formulation is obtained from an appropriate combination of a mixed finite element approach with a Dirichlet-to-Neumann method. The derivation of our results is based on some tools from nonlinear functional analysis and the Babuska-Brezzi theory for variational problems with constraints. 相似文献
996.
N. V. Pratsevityi 《Ukrainian Mathematical Journal》1998,50(8):1233-1241
We study the fractal properties of a convolution of two Cantor distributions. By using the method of characteristic functions,
we establish sufficient conditions for the singularity of the convolution of an arbitrary finite number of distributions of
random variables with independent s-adic digits. We disprove the hypothesis on the validity of a “singular analog” of the Jessen-Wintner theorem for anomalously
fractal distributions.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 50, No. 8, pp. 1082–1088, August, 1998.
The present work was partially supported by the International Soros Program of Educational Support in Exact Sciences (grant
No. APU 061086). 相似文献
997.
998.
999.
1000.
The dependence of the type of magnetic ordering in multilayer structures on the magnitude of the exchange interaction between
the magnetic layers and on the degree of roughness of the interfaces between the layers is investigated. In the case of a
three-layer system the regions of existence of the domain structure, of noncollinear ordering of the homogeneous magnetic
layers, and of the collinear ferromagnetic phase and collinear antiferromagnetic phase are found.
Fiz. Tverd. Tela (St. Petersburg) 39, 1244–1247 (July 1997) 相似文献