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941.
C. Foias A. E. Frazho I. Gohberg M. A. Kaashoek 《Integral Equations and Operator Theory》1997,29(4):455-490
The family of all solutions of the three chains completion problem with a prescribed tolerance is described explicitly. It is shown that this family can be parameterized by a natural set of contractive upper triangular operators. As an application all solutions to a suboptimal nonstationary Nehari problem are described. 相似文献
942.
943.
We consider a particular case of the matrix Carleman problem for two pairs of functions in a ring and find a constructive
solution of this problem. In addition, we propose an algorithm for the construction of solutions for two infinite systems
of smooth transition and for a system of two singular equations of special type.
Translated from Ukrainskii Matematicheskii Zhurnal, Vol. 49, No. 5, pp. 662–671, May, 1997 相似文献
944.
In the case of number fields the embedding problem of a p-extension with non-Abelian kernel of order p4 is studied. The two kernels of order 34 with generators α, γ and relations α9 = 1, [α,α]3=1,[α,αγγ]==1,[αγγ]=α3,γ3=1 or γ3=α3 and the kernel of order 24 with generators α, β, γ and relations α4=1 β2,[αγ]=1, [α,γ]=1,[βγ]=α2 are considered. For kernels of odd order the embedding problem is always solvable. For the kernel of order 16 the solvability
conditions are reduced to those for the associated problems at the Archimedean points, and to the compatibility condition.
Bibliography: 9 titles.
Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 227, 1995, pp. 74–82. 相似文献
945.
To establish H2 CARS thermometry at high pressure, accumulated H2
Q-branch CARS spectra were recorded in the exhaust of a fuel-rich CH4/air flame at pressures between 5 and 40 bar. Temperatures were deduced by fitting theoretical spectra to experimental data points. The Energy-Corrected Sudden (ECS) scaling law was employed to set up an empirical model for the calculation of H2 linewidths in high-pressure hydrocarbon flames with H2 as a minority species. Experimental H2 CARS spectra could be simulated very accurately with this model. The evaluated temperatures agreed well with reference temperatures obtained by spontaneous rotational Raman scattering of N2. 相似文献
946.
947.
Stationary solitons are found to occur in two-dimensional media with a variable saturation magnetization whose square is a
harmonic function of the coordinates. It is shown in this case that the Landau-Lifshits equation can be reduced to the integrable
O(3) sigma-model in curved space. Some properties of the solutions obtained are discussed. Bibliography: 15 titles.
Translated by V. D. Lipovskii. 相似文献
948.
949.
Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 12, p. 2899, December, 1991. 相似文献
950.