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61.
We present a new modification of the Newton’s method which produces iterative methods with order of convergence three. A general error analysis providing the higher order of convergence is given, and the best efficiency, in term of function evaluations, of two of this new methods is provided. 相似文献
62.
Rolando Cavazos-Cadena Emmanuel Fernández-Gaucherand 《Mathematical Methods of Operations Research》1995,41(1):89-108
We consider discrete-time nonlinear controlled stochastic systems, modeled by controlled Makov chains with denumerable state space and compact action space. The corresponding stochastic control problem of maximizing average rewards in the long-run is studied. Departing from the most common position which usesexpected values of rewards, we focus on a sample path analysis of the stream of states/rewards. Under a Lyapunov function condition, we show that stationary policies obtained from the average reward optimality equation are not only average reward optimal, but indeed sample path average reward optimal, for almost all sample paths.Research supported by a U.S.-México Collaborative Research Program funded by the National Science Foundation under grant NSF-INT 9201430, and by CONACyT-MEXICO.Partially supported by the MAXTOR Foundation for applied Probability and Statistics, under grant No. 01-01-56/04-93.Research partially supported by the Engineering Foundation under grant RI-A-93-10, and by a grant from the AT&T Foundation. 相似文献
63.
We develop a simple theory of André-Quillen cohomology for commutative differential graded algebras over a field of characteristic zero. We then relate it to the homotopy groups of function spaces and spaces of homotopy self-equivalences of rational nilpotent CW-complexes. This puts certain results of Sullivan in a more conceptual framework. 相似文献
64.
We introduce a master–worker framework for parallel global optimization of computationally expensive functions using response surface models. In particular, we parallelize two radial basis function (RBF) methods for global optimization, namely, the RBF method by Gutmann [Gutmann, H.M., 2001a. A radial basis function method for global optimization. Journal of Global Optimization 19(3), 201–227] (Gutmann-RBF) and the RBF method by Regis and Shoemaker [Regis, R.G., Shoemaker, C.A., 2005. Constrained global optimization of expensive black box functions using radial basis functions, Journal of Global Optimization 31, 153–171] (CORS-RBF). We modify these algorithms so that they can generate multiple points for simultaneous evaluation in parallel. We compare the performance of the two parallel RBF methods with a parallel multistart derivative-based algorithm, a parallel multistart derivative-free trust-region algorithm, and a parallel evolutionary algorithm on eleven test problems and on a 6-dimensional groundwater bioremediation application. The results indicate that the two parallel RBF algorithms are generally better than the other three alternatives on most of the test problems. Moreover, the two parallel RBF algorithms have comparable performances on the test problems considered. Finally, we report good speedups for both parallel RBF algorithms when using a small number of processors. 相似文献
65.
Wang Xiaoyu Wang Pingjiang Chen Jihong 《International Journal of Infrared and Millimeter Waves》2007,28(1):99-111
Infrared camera has been widely used in electrical power systems for predictive and preventive thermal fault diagnosis. Without
historical IR images being considered, most thermograph analysis used at present are concerned with static image. The dynamic
history and tendency analysis which compares the newly taken image with historical images is particularly attractive. Conclusions
can be drawn from temperature variations rather than just from anomalous thermal pattern. However the spatial distortions
prevent such dynamic analysis from being practicable. So the need to register infrared images arises. This paper proposes
an automatic registration algorithm based on closed temperature contour matching for infrared image series of a target equipment
taken at different times. Centroid Distance Function is used in image registration for the first time. The algorithm can remove
spatial distortions, bring temperature variations into prominence and endow infrared camera with dynamic analysis ability.
Experiment shows that the algorithm is simple, effective and extensible. 相似文献
66.
TheInterpolationProblemontheMaximalIdealSpaceofH~∞¥GuoKungu(郭坤宇)(DepartmentofMathematics,SichuanUniversity,Chengdu,610064)Abs?.. 相似文献
67.
带时滞观测线性离散系统的递推滤波 总被引:1,自引:0,他引:1
何关钰 《高校应用数学学报(A辑)》1992,7(2):206-215
本文讨论带时滞观测线性离散系统的滤波问题,提出利用联合分布函数,得到滤波递推格式.这种方法还适用于一般的带有状态时滞的线性离散系统. 相似文献
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