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951.
Svend-Holger Friis Ulrich Rieder Jürgen Weishaupt 《Mathematical Methods of Operations Research》1993,37(2):187-205
A general single-server queueing network model is considered. It is well-known that an optimal policy is determined by the largest-index policy. There is an index for each given queue and one allocates the server to a queue with largest current index. Using discounted dynamic programming we give a new and short proof of this result and derive some characterizations and bounds of the indices. Moreover, it is shown that an approximate largest-index policy yields an approximately optimal policy. These results lead to efficient methods for computing the indices. In particular, we present a general largest-remaining-index method. 相似文献
952.
Dirk H. Rischke Yariş Pürsün Joachim A. Maruhn Horst Stöcker Walter Greiner 《Acta Physica Hungarica A》1995,1(3-4):309-322
It is shown that in ideal relativistic hydrodynamics a phase transition from hadron to quark and gluon degrees of freedom in the nuclear matter equation of state leads to a minimum in the excitation function of the transverse collective flow. 相似文献
953.
Global solutions for quasilinear parabolic problems 总被引:4,自引:0,他引:4
Results on the global existence of classical solutions for quasilinear parabolic equations in bounded domains with homogeneous
Dirichlet or Neumann boundary conditions are presented. Besides quasilinear parabolic equations, the method is also applicable
to some weakly-coupled reaction-diffusion systems and to elliptic equations with nonlinear dynamic boundary conditions.
Received December 21, 2000; accepted August 30, 2001. 相似文献
954.
The theory of transmission fluctuation spectrometry (TFS) was recently developed for particle size analysis in dilute flowing particle suspensions, whereby the statistical transmission fluctuations are used to extract the particle size distribution and particle concentration. 相似文献
955.
Ulrich Ellwanger Manfred Hirsch Axel Weber 《Zeitschrift fur Physik C Particles and Fields》1996,69(4):687-697
Wilson’s exact renormalization group equations are derived and integrated for the relevant part of the pure Yang-Mills action. We discuss in detail how modified Slavnov—Taylor identities control the breaking of BRST invariance in the presence of a finite infrared cutoff k through relations among different parameters in the effective action. In particular they imply a nonvanishing gluon mass term for nonvanishing k. The requirement of consistency between the renormalization group flow and the modified Slavnov—Taylor identities allows to control the self—consistency of truncations of the effective action. 相似文献
956.
Joachim Toft 《Bulletin des Sciences Mathématiques》2002,126(2):115-142
We study continuity properties for a family {sp}p?1 of increasing Banach algebras under the twisted convolution, which also satisfies that a∈sp, if and only if the Weyl operator aw(x,D) is a Schatten-von Neumann operator of order p on L2. We discuss inclusion relations between the sp-spaces, Besov spaces and Sobolev spaces. We prove also a Young type result on sp for dilated convolution. As an application we prove that f(a)∈s1, when a∈s1 and f is an entire odd function. We finally apply the results on Toeplitz operators and prove that we may extend the definition for such operators. 相似文献
957.
Emma Thorn-Cs nyi J rg Ulrich Zilles 《Journal of molecular catalysis. A, Chemical》2002,190(1-2):85-100
The structure/property relationship of Schrock-type alkylidene complexes with tungsten and molybdenum as central atoms was investigated. Terminal and, E and Z internal olefins as well as double bond substituted and unsubstituted unsaturated polymers served as metathesis substrates. According to the results obtained, it is possible to choose the optimal catalyst depending on the metathesis substrate and temperature, the central atom plays a decisive role. Examples concerning equilibrium polymerization demonstrate the practical utilization. 相似文献
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