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101.
102.
A simple model has been developed to describe the Zeeman patterns of far-infrared laser magnetic resonance spectra of the monobromomethyl radical CH2Br observed at 447.3 and 671.1μm. A satisfactory agreement between the experimental spectra of the radical and their simulation with this simple model has been achieved. This approach can be used to gain further information about the structure and the spectrum of this interesting radical. 相似文献
103.
Oleg Borodin 《Combinatorica》1993,13(1):121-125
The weight of an edge in a graph is the sum of the degrees of its end-vertices. It is proved that in each 3-polytope there exists either an edge of weight at most 13 for which both incident faces are triangles, or an edge of weight at most 10 which is incident with a triangle, or else an edge of weight at most 8. All the bounds 13, 10, and 8 are sharp and attained independently of each other. 相似文献
104.
S. A. Plaksa 《Ukrainian Mathematical Journal》1993,45(8):1316-1320
Under the minimal assumptions imposed on given spaces, the sufficient conditions are established, under which the compositionBA of operatorsA andB has the Noether property and is normally solvable. Similar conditions, guaranteeing that the operatorA is normally solvable or possesses the Noether property, are obtained for the operatorsB andBA.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 8, pp. 1177–1180, August, 1993. 相似文献
105.
The nonlinear Schrödinger-type equations invariant with respect to the extended Galilean group are described. We study the conditional symmetry of such equations, realize the reduction procedure, and construct the classes of exact solutions.Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 45, No. 4, pp. 539–551, April, 1993. 相似文献
106.
B. Z. Shavarov'skyy 《Ukrainian Mathematical Journal》1992,44(12):1572-1574
The decomposability of matrix polynomials with commuting coefficients of quasi-simple structure into regular factors and the solvability of the corresponding matrix polynomial one-sided equations are investigated.Translated from Ukrainskii Matematicheskie Zhurnal, Vol. 44, No. 12, pp. 1716–1718, December, 1992. 相似文献
107.
108.
I. V. Gaishun 《Proceedings of the Steklov Institute of Mathematics》2006,255(2):S47-S53
For a linear nonautonomous system with one output, the existence conditions for an identifier that estimates the current state with exponential rate are established. An algorithm for constructing such an identifier is described and its dependence on small perturbations of coefficients is studied. 相似文献
109.
In this work two non-local problems for the parabolic-hyperbolic type equation with non-characteristic line of changing type
are considered. Unique solvability of these problems is proven. The uniqueness of the solution is proven by the method of
energy integrals and the existence is proven by the method of integral equations. 相似文献
110.
We prove that any 43-fold covering of the plane with translates of a triangle can be decomposed into two coverings. 相似文献