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981.
Gustavo?Berganti?os Leticia?LorenzoEmail author 《Mathematical Methods of Operations Research》2004,59(3):393-403
We associate to each cost spanning tree problem a non-cooperative game, which is inspired by a real-life problem. We study the Nash equilibria and subgame perfect Nash equilibria of this game. We prove that these equilibria are closely related with situations where agents connect sequentially to the source.Finicial support from the Ministerio de Ciencia y Tecnologia and FEDER, and Xunta de Galicia through grants BEC2002-04102-C02-01 and PGIDIT03PXIC30002PN is gratefully acknowledged. 相似文献
982.
指出部分大学物理教材中,用完全非弹性碰撞方法推导相对论动量定义式时,必须附加系统质量守恒这一“预期论据”,从而存在着违反逻辑规则等问题. 相似文献
983.
Benzylpyridinium ions, generated via electrospray ionization of dilute solutions of their salts in acetonitrile/water, are probed by collisional activation in an ion-trap mass spectrometer. From the breakdown diagrams obtained, phenomenological appearance energies of the fragment ions are derived. Comparison of the appearance energies with calculated reaction endothermicities shows a reasonably good correlation for this particular class of compounds. In addition, the data indirectly indicate that at threshold the dissociation of almost all of the benzylpyridinium ions under study leads to the corresponding benzylium ions, rather than the tropylium isomers. Substituent effects on the fragmentation for a series of benzylpyridinium ions demonstrate that neither mass effects nor differences in density of states seriously affect the energetics derived from the ion-trap experiments. 相似文献
984.
Two separate algorithms for calculating the intermediate states, using cellular automata, and the initial conditions in the rate matrix for the diffusion–collision model are introduced. They enable easy and fast calculations of the folding probabilities of the intermediate states, even for a very large number of microdomains. © 2000 John Wiley & Sons, Inc. J Comput Chem 21: 923–932, 2000 相似文献
985.
Probing the color structure of the perfect QCD fluids via soft-hard-event-by-event azimuthal correlations 下载免费PDF全文
We develop a comprehensive dynamical framework, CIBJET, to calculate on an event-by-event basis the dependence of correlations between soft(p_T2 GeV) and hard(p_T10 GeV) azimuthal flow angle harmonics on the color composition of near-perfect QCD fluids produced in high energy nuclear collisions at RHIC and LHC. CIBJET combines consistently predictions of event-by-event VISHNU2+1 viscous hydrodynamic fluid fields with CUJET3.1 predictions of event-by-event jet quenching. We find that recent correlation data favor a temperature dependent color composition including bleached chromo-electric q(T) + g(T) components and an emergent chromo-magnetic degrees of freedom m(T) consistent with non-perturbative lattice QCD information in the confinement/deconfinement temperature range. 相似文献
986.
987.
We present an algorithm for finding a minimum spanning tree where the costs are the sum of two linear ratios. We show how upper and lower bounds may be quickly generated. By associating each ratio value with a new variable in `image space,' we show how to tighten these bounds by optimally solving a sequence of constrained minimum spanning tree problems. The resulting iterative algorithm then finds the globally optimal solution. Two procedures are presented to speed up the basic algorithm. One relies on the structure of the problem to find a locally optimal solution while the other is independent of the problem structure. Both are shown to be effective in reducing the computational effort. Numerical results are presented. 相似文献
988.
We show that if G is a simple connected graph with and , then G has a spanning tree with > t leaves, and this is best possible. © 2001 John Wiley & Sons, Inc. J Graph Theory 37: 189–197, 2001 相似文献
989.
对树的3-彩虹控制数进行研究,首先用构造法找到直径较小的树的3-彩虹控制数的上界.再通过分类讨论思想和数学归纳法得到一般的阶n大于等于5的树的3-彩虹控制数的上界. 相似文献
990.
Scenario tree modeling for multistage stochastic programs 总被引:2,自引:0,他引:2
An important issue for solving multistage stochastic programs consists in the approximate representation of the (multivariate) stochastic input process in the form of a scenario tree. In this paper, we develop (stability) theory-based heuristics for generating scenario trees out of an initial set of scenarios. They are based on forward or backward algorithms for tree generation consisting of recursive scenario reduction and bundling steps. Conditions are established implying closeness of optimal values of the original process and its tree approximation, respectively, by relying on a recent stability result in Heitsch, Römisch and Strugarek (SIAM J Optim 17:511–525, 2006) for multistage stochastic programs. Numerical experience is reported for constructing multivariate scenario trees in electricity portfolio management. 相似文献