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971.
Sturm's chain technique for evaluation of a number of real roots of polynomials is applied to construct a simple algorithm for global optimization of polynomials or generally for rational functions of finite global minimal value. The method can be applied both to find the global minimum in an interval or without any constraints. It is shown how to use the method to minimize globally a truncated Fourier series. The results of numerical tests are presented and discussed. The cost of the method scales as the square of the degree of the polynomial. 相似文献
972.
以各类特殊函数与S turm-L iouv ille本征方程之间关系为基础,导出了一个计算各类特殊函数模积分的一个统一公式,这样不仅避免了过去要对不同的特殊函数分别用不同方法计算模的积分,而且使模的计算本身得到较大简化. 相似文献
973.
The EMF concentration cell method was applied to determine excess partial molar thermodynamic functions for some sections of the systems Tl?Ag?Te and Tl?Sb?Te. The presence of binary and ternary associates is assumed in Tl?Ag?Te solutions. 相似文献
974.
B. S. Goh 《Journal of Optimization Theory and Applications》1997,92(3):581-604
Existing algorithms for solving unconstrained optimization problems are generally only optimal in the short term. It is desirable to have algorithms which are long-term optimal. To achieve this, the problem of computing the minimum point of an unconstrained function is formulated as a sequence of optimal control problems. Some qualitative results are obtained from the optimal control analysis. These qualitative results are then used to construct a theoretical iterative method and a new continuous-time method for computing the minimum point of a nonlinear unconstrained function. New iterative algorithms which approximate the theoretical iterative method and the proposed continuous-time method are then established. For convergence analysis, it is useful to note that the numerical solution of an unconstrained optimization problem is none other than an inverse Lyapunov function problem. Convergence conditions for the proposed continuous-time method and iterative algorithms are established by using the Lyapunov function theorem. 相似文献
975.
V. G. Krotov 《Mathematical Notes》1997,62(4):439-448
In the critical case αp=n functions from the Hardy-Sobolev spacesH
α
p
(B
n
) have a limit almost everywhere on the boundary along certain regions of exponential contact with the boundary. It is proved
in the paper that the maximal operator associated with these regions is bounded as an operator fromH
α
p
(B
n
) toL
p
(ϖB
n
).
Translated fromMatematicheskie Zametki, Vol. 62, No. 4, pp. 527–539, October, 1997.
Translated by N. K. Kulman 相似文献
976.
Given a compact metric space X and a continuous map f from X to itself, we construct a barrier function for chain-recurrence. We use it to endow the space of chain-transitive components with a non-trivial ultrametric distance and to construct Lyapunov functions for f. Most of these constructions are then generalized on an arbitrary separable metric space to a continuous compactum-valued map. 相似文献
977.
We obtain a joint limit theorem in the space of analytic functions for Lerch zeta-functions with algebraic irrational parameter.
The research was partially supported by the Lithuanian State Science and Studies Foundation, grant No. T-81/09. 相似文献
978.
P. Maréchal 《Journal of Optimization Theory and Applications》2005,126(2):357-366
Algebraic properties of the functional operation introduced in Part 1 of this paper (Ref. 1) are considered. In essence, the functional operation is shown to be associative, right distributive with respect to addition, and left distributive with respect to epigraphic sum. 相似文献
979.
Prof. Dr. U. Rieder 《Mathematical Methods of Operations Research》1991,35(6):473-490
A general partially observed control model with discrete time parameter is investigated. Our main interest concerns monotonicity results and bounds for the value functions and for optimal policies. In particular, we show how the value functions depend on the observation kernels and we present conditions for a lower bound of an optimal policy. Our approach is based on two multivariate stochastic orderings: theTP
2 ordering and the Blackwell ordering.Dedicated to Prof. Dr. K. Hinderer on the occassion of his 60th birthday 相似文献
980.
Victor J.W. Guo Martin Rubey Jiang Zeng 《Journal of Combinatorial Theory, Series A》2006,113(7):1501-1515
Recently, Guo and Zeng discovered two families of polynomials featuring in a q-analogue of Faulhaber's formula for the sums of powers and a q-analogue of Gessel-Viennot's formula involving Salié's coefficients for the alternating sums of powers. In this paper, we show that these are polynomials with symmetric, nonnegative integral coefficients by refining Gessel-Viennot's combinatorial interpretations. 相似文献