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961.
In this paper, we prove that every automorphism of the semigroup of invertible matrices with nonnegative elements over a linearly
ordered associative ring on some specially defined subgroup coincides with the composition of an inner automorphism of the
semigroup, an order-preserving automorphism of the ring, and a central homothety.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 2, pp. 3–23, 2005. 相似文献
962.
963.
A. M. Raigorodskii 《Journal of Mathematical Sciences》2007,146(2):5723-5730
This work deals with some problems on the embeddings of finite geometric graphs into the random ones. In particular, we study here applications of the random graph theory to the Nelson-Erdös-Hadwiger problem on coloring spaces. 相似文献
964.
965.
A. V. Pukhlikov 《Journal of Mathematical Sciences》2007,140(2):303-320
Combining the connectedness principle of Shokurov and Kollár, we develop a new technique of studying birational maps of natural
Fano fiber spaces. We prove that the only structures of a rationally connected fibration on direct products of typical Fano
varieties are projections onto the factors. In particular, the groups of biregular and birational self-maps of Fano direct
products coincide.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 10, No. 4, pp. 183–206, 2004. 相似文献
966.
We consider a nonlinear optimal control problem with an integral functional in which the integrand is the characteristic function
of a closed set in the phase space. An approximation method is applied to prove the necessary conditions of optimality in
the form of a Pontryagin maximum principle without any prior assumptions on the behavior of the optimal trajectory. Similarly
to phase-constrained problems, we derive conditions of nondegeneracy and pointwise nontriviality of the maximum principle.
__________
Translated from Nelineinaya Dinamika i Upravlenie, No. 4, pp. 179–204, 2004. 相似文献
967.
968.
A. D. Lapin 《Acoustical Physics》2007,53(1):11-15
The problem of scattering of a Rayleigh wave by a chain of identical closely spaced monopole-dipole resonators with friction is considered. The values of resonator parameters that provide the rejection of the Rayleigh wave are found. The conditions under which the Rayleigh wave is much more efficiently reflected by the dipole resonators than by the monopole ones are determined. 相似文献
969.
V. E. Zubov A. D. Kudakov N. L. Levshin 《Bulletin of the Russian Academy of Sciences: Physics》2007,71(11):1548-1549
It is established that reversible adsorption of water and methyl alcohol molecules, occurring via formation of hydrogen bonds, changes the dynamic properties of domain walls in the surface region of soft ferromagnets, as well as their initial static magnetic susceptibility. A mechanism is proposed for the effects revealed. 相似文献
970.
The effect of variation of the scattered light intensity in a magnetic fluid with aggregates of magnetite particles several microns in size under the action of a magnetic field is studied. The effect relaxation times are determined when the magnetic field is turned on and off. This effect is found to be caused by the orientation of anisotropically magnetized aggregates. Experimental data are used to calculate the average anisotropy of the magnetic susceptibility of the aggregate and estimate its magnetic permeability. 相似文献