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961.
M. Yu. Kulikov 《Radiophysics and Quantum Electronics》2004,47(9):662-673
On the example of the effect of an atmospheric wave with given amplitude on the density oscillations of minor gas constituents near the mesopause (at heights 80–90 km, we consider the influence of the quasi-resonant periodic spatial transport on a distributed system responding subharmonically to a periodic external action (diurnal sunlight variations). Numerical modeling revealed the formation of a coherent horizontal distribution of the dynamical variables (i.e., the concentrations of small constituents). Application of this effect to the mesopause conditions is discussed.Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 47, No. 9, pp. 739–752, September, 2004. 相似文献
962.
A. Yu. Kolesov E. F. Mishchenko N. Kh. Rozov 《Proceedings of the Steklov Institute of Mathematics》2007,256(1):206-222
The well-known sine-Gordon equation, supplemented with small damping and small quasiperiodic external force, is studied under the zero Dirichlet boundary conditions at the endpoints of a finite interval. The main assumption is that all frequencies of the external force are in 1:1 resonance with certain eigenfrequencies of the unperturbed equation; i.e., the socalled fundamental multifrequency resonance is observed. It is shown that in this case, by an appropriate choice of the parameters of the external force, one can make it so that the boundary value problem has a stable invariant torus of any finite dimension that bifurcates from zero on any preassigned finite set of spatial modes. It is also shown (by numerical analysis) that in a number of cases the above-mentioned torus coexists with a chaotic attractor. 相似文献
963.
We discuss differential equations with nonlinear boundary conditions. We formulate sufficient conditions under which problems
with deviating arguments have quasisolutions or solutions. To obtain the results, we apply the method of monotone iterations. 相似文献
964.
G. I. Petrashen V. V. Reshetnikov Yu. A. Surkov 《Journal of Mathematical Sciences》2007,142(6):2645-2654
A nonstationary problem concerning the propagation of low-frequency waves for a model that consists of a packet of elastic
layers lying on an elastic half-space is considered, and exact mathematical solutions in the form of repeated integrals are
constructed in three basic forms. It is proved that these solutions satisfy initial conditions. The representation of solutions
as a superposition of multiple waves is treated. Bibliography: 6 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 332, 2006, pp. 220–239. 相似文献
965.
O. Yu. Ivanova 《Journal of Mathematical Sciences》2007,147(5):7088-7097
A complete two-dimensional local field K of mixed characteristic with finite second residue field is considered. The existence
of a completely ramified extension L of K such that L is a standard field is assumed. It is proved that the rank of the quotient
U(1)K
2
top
K/TK, where TK is the closure of the torsion subgroup, is equal to the degree of the constant subfield of K over ℚp. I. B. Zhukov constructed a set of generators of this quotient in the case where K is a standard field. In this paper, two
natural generalizations of this set are considered, and it is proved that one of them generates the entire group and the other
generates its subgroup of finite index. Bibliography: 5 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 343, 2007, pp. 206–221. 相似文献
966.
967.
S. A. Shiryaev M. V. Atamanov M. I. Guseva Yu. V. Martynenko A. V. Mitin V. S. Mitin P. G. Moskovkin 《Technical Physics》2002,47(2):238-243
It is suggested to produce metal-carbon composite coatings by magnetron sputtering of mosaic cathodes, which are Group IV,
V, and VI metals. The mosaic structure of the cathode elements are computer-optimized for each of the metals. Reflection electron
diffraction studies show that the coatings have the amorphous or nanocrystalline structures, which are thermally stable. The
coatings offer specific physical properties, in particular, low friction factor and high hardness. 相似文献
968.
RupingZou AibingYu 《中国颗粒学报》2003,1(1):27-32
The initial forming of fiber blend to high green density, i.e. the packing of fibrous particles, is important to the reinforcement of composite materials. It is very useful to develop a general predictive method for the optimum selection of particle mixtures for the property control of ceramic or composite products. This paper presents such a mathematical model developed on the basis of the similarity analysis between the spherical and non-spherical particle packings and assesses its applicability to the packing of fibrous particles with discrete and/or continuous length distributions. The results indicate that the model can predict this packing system well and hence provide an effective way to solve various packing problems in the composite materials processing. 相似文献
969.
T. F. Sysoeva Z. A. Starikova M. V. Leont'eva N. M. Dyatlova 《Journal of Structural Chemistry》1991,31(5):814-817
All-Union Research Institute for Chemical Reagents and High-Purity Chemicals. Translated from Zhurnal Strukturnoi Khimii, Vol. 31, No. 5, pp. 140–143, September–October, 1990. 相似文献
970.
A. Yu. Konstantinov 《Ukrainian Mathematical Journal》1995,47(5):760-772
We establish theorems about the expansion of nonuniformly right-definite multiparameter problems in generalized eigenfunctions. We also give an abstract criterion of existence of commuting self-adjoint extensions of a family of symmetric operators.To Yurii Makarovich BerezanskiiTranslated from Ukrainskii Matematicheskii Zhurnal, Vol. 47, No. 5, pp. 659–670, May, 1995.This research was supported by the Ukrainian State Committee on Science and Technology. 相似文献