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排序方式: 共有8964条查询结果,搜索用时 15 毫秒
991.
An existence theorem of two positive solutions of the singular BVP1/(p(t))(p(t)y′(t))′+λα(t)f(y(t))=0,t∈(0,1),αy(0)-βp(t)y′(t)=0=γy(1)+δp(t)y′(t)was established by using topological degree theory. 相似文献
992.
Stephan Dahlke 《manuscripta mathematica》1998,95(1):59-77
This paper is concerned with some theoretical foundations for adaptive numerical methods for elliptic boundary value problems.
The approximation order that can be achieved by such an adaptive method is determined by certain Besov regularity of the weak
solution. We study Besov regularity for second order elliptic problems in bounded domains in ℝ
d
. The investigations are based on intermediate Schauder estimates and on some potential theoretic framework. Moreover, we
use characterizations of Besov spaces by wavelet expansions.
This work has been supported by the Deutsche Forschungsgemeinschaft (Da 360/1-1) 相似文献
993.
周勇 《数学物理学报(A辑)》1997,17(3):245-254
文中证明了核邻型的光滑条件分位过程的强逼近,获得了其一致逼近速度.并由此结果推导出了光滑条件分位估计的渐近正态性、弱收敛和对数律等深刻结果. 相似文献
994.
ZHANGSHENGKAI YANHUIZHEN ZHANGYADONG 《高校应用数学学报(英文版)》1997,12(2):205-214
In this paper we have studied n-person game problems of (0,1) normalization and composition. Also we have concerned multilinear extensions of composition games and especial games [5-7,9-14]. As we have studied Shapley value [1-4,15], we will give some proofs of the the orems. 相似文献
995.
In this paper we consider generalized convexity and concavity properties of the optimal value functionf
* for the general parametric optimization problemP(ε) of the form min
x
f(x, ε) s.t.x∈R(ε). Many results on convexity and concavity characterizations off
* were presented by the authors in a previous paper. Such properties off
* and the solution set mapS
* form an important part of the theoretical basis for sensitivity, stability and parametric analysis in mathematical optimization.
We give sufficient conditions for several types of generalized convexity and concavity off
*, in terms of respective generalized convexity and concavity assumptions onf and convexity and concavity assumptions on the feasible region point-to-set mapR. Specializations of these results to the parametric inequality-equality constrained nonlinear programming problem are provided.
Research supported by Grant ECS-8619859, National Science Foundation and Contract N00014-86-K-0052, Office of Naval Research. 相似文献
996.
997.
It always takes time for people to digest information and make judgments. The decision maker's preference is not always clear and stable when decision analysis and decision making are performed. In this paper, we introduce a generalized preference structure to cope with indefinite preferences. We describe its general properties, its implication on value function representation, its solution concepts, and methods for obtaining the solutions.This research has been partially supported by NSF Grant No. IST-84-18863. The authors are grateful to Dr. D. J. White for his helpful comments on a previous draft. 相似文献
998.
This paper deals with the solvability of boundary value problems for singular integral equations of the form (i)-(ii).By an algebraic method we reduce the problem (i)-(ii) to a system of linear algebraic equations which gives all solutions in a closed form.AMS Subject Classification: 47G05, 45GO5, 45E05 相似文献
999.
Konstantin Volosov Gautam Mitra Fabio Spagnolo Cormac Lucas 《Computational Optimization and Applications》2005,32(1-2):179-207
In this paper we formulate a model for foreign exchange exposure management and (international) cash management taking into consideration random fluctuations of exchange rates. A vector error correction model (VECM) is used to predict the random behaviour of the forward as well as spot rates connecting dollar and sterling. A two-stage stochastic programming (TWOSP) decision model is formulated using these random parameter values. This model computes currency hedging strategies, which provide rolling decisions of how much forward contracts should be bought and how much should be liquidated.The model decisions are investigated through ex post simulation and backtesting in which value at risk (VaR) for alternative decisions are computed. The investigation (a) shows that there is a considerable improvement to “spot only” strategy, (b) provides insight into how these decisions are made and (c) also validates the performance of this model. 相似文献
1000.
Lord–;Shulman's system of partial differential equations of generalized thermoelasticity [1] is considered, in which the finite velocity of heat propagation is taken into account by introducing a relaxation time constant. General aspects of the theory of boundary value and initial-boundary value problems and representation of solutions by series and quadratures are considered using the method of a potential. 相似文献