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排序方式: 共有10000条查询结果,搜索用时 0 毫秒
991.
We construct a three-parameter family of contact metric structures on the unit tangent sphere bundle T
1
M of a Riemannian manifold M and we study some of their special properties related to the Levi-Civita connection. More precisely, we give the necessary
and sufficient conditions for a constructed contact metric structure to be K-contact, Sasakian, to satisfy some variational conditions or to define a strongly pseudo-convex CR-structure. The obtained
results generalize classical theorems on the standard contact metric structure of T
1
M. 相似文献
992.
We consider some regression relations for record values X(n), n > 0, generated by a sequence of independent random variables
X1, X2, X3,... with a common continuous cumulative distribution function F(x). New characterizations of distributions based on regression
properties of record values are obtained. Bibliography: 7 titles.
__________
Translated from Zapiski Nauchnykh Seminarov POMI, Vol. 339, 2006, pp. 5–14. 相似文献
993.
M. A. Kachalova 《Journal of Mathematical Sciences》2007,140(5):699-715
The additive structure of the Hochschild cohomology ring for a Möbius algebra is described. We use the structure of the bimodule minimal projective resolution of the algebra, constructed in a previous paper. Bibliography: 4 titles. 相似文献
994.
995.
We consider the interpolation Nevanlinna-Pick problem with infinitely many interpolation nodes in the class S[a, b] and rational matrix functions associated with this problem and orthogonal on the segment [a, b]. We obtain a criterion of complete indeterminacy of the Nevanlinna-Pick problem in terms of orthogonal rational matrix functions.
__________
Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 59, No. 6, pp. 764–770, June, 2007. 相似文献
996.
On the properties of solutions to the Goursat-Darboux problem with boundary and distributed controls
N. I. Pogodaev 《Siberian Mathematical Journal》2007,48(5):897-912
We consider a control system described by the Goursat-Darboux equation. The system is controlled by distributed and boundary controls. The controls are subject to the constraints given as multivalued mappings with closed, possibly nonconvex, values depending on the phase variable. Alongside the initial constraints, we consider the convexified constraints and the constraints whose values are the extreme points of the convexified constraints. We study the questions of existence of solutions and establish connections between the solutions under various constraints. 相似文献
997.
Sh. R. Shakirov 《Theoretical and Mathematical Physics》2007,153(2):1477-1486
We propose a method for constructing systems of polynomial equations that define submanifolds of degenerate binary forms of
an arbitrary degeneracy degree.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 153, No. 2, pp. 147–157, November, 2007. 相似文献
998.
999.
L. S. Pul’kina 《Journal of Mathematical Sciences》2007,144(1):3832-3840
The author proves the existence and uniqueness of a generalized solution of a nonlocal problem with an integral condition
for a hyperbolic equation with n spatial variables.
This work is a continuation of the studies started in [3–5], where the solvability problem of nonlocal problems with an integral
condition was studied for hyperbolic equations on the plane.
__________
Translated from Sovremennaya Matematika i Ee Prilozheniya (Contemporary Mathematics and Its Applications), Vol. 33, Suzdal
Conference-2004, Part 1, 2005. 相似文献
1000.
V. M. Budanov 《Journal of Mathematical Sciences》2007,146(3):5931-5937
This paper investigates algorithms of motion planning for a six-legged walking machine over complex terrain. Application of
the Rodrigues-Hamilton parameters for describing the orientation of the body enables one to develop algorithms of motion planning
for the body and legs in an absolute coordinate frame with automatic adaptation to the surface. Experiments with a laboratory
scale walking machine have demonstrated the efficiency of proposed algorithms.
__________
Translated from Fundamentalnaya i Prikladnaya Matematika, Vol. 11, No. 7, pp. 197–206, 2005. 相似文献