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We consider a Markov decision process (MDP) under average reward criterion. We investigate the decomposition of such MDP into smaller MDPs by using the strongly connected classes in the associated graph. Then, by introducing the associated levels, we construct an aggregation-disaggregation algorithm for the computation of an optimal strategy for the original MDP. 相似文献
995.
Summary Jellium metal surface properties such as the surface dipole barrier and work function are studied in the linear potential
approximation to the effective potential at the surface. The metal surface position and field strength are determined respectively
by the requirement of overall charge neutrality and the constraintst on the electrostatic potential by the Budd-Vannimenus theorem. The calculations are primarily analytic and these properties
are given in terms of the universal function of the field strength. The results obtained employing the Ceperley-Alder expression
for the correlation energy closely approximate those of Lang and Kohn. 相似文献
996.
R.A. Mohammed A.I. Bailey P.F. Luckham S.E. Taylor 《Colloids and surfaces. A, Physicochemical and engineering aspects》1993,80(2-3):237-242
The importance of the interfacial rheology in determining the stability of water-in-Buchan crude oil emulsions has been demonstrated in part 1 of this series of papers (R.A. Mohammed, A.I. Bailey, P.F. Luckham and S.E. Taylor, Colloids Surfaces A: Physicochem. Eng. Aspects, 80(1993)223). In part 2, interfacial tensions of crude oil, and solutions of asphaltenes and resins in a model oil have been investigated. Surface pressure vs. area (Π—A) curves of monolayers of asphaltenes, resins and their mixtures have been established. In its dependence on the ratio of resins to asphaltenes, the pseudostatic dilatational modulus has high values for low resin-to-asphaltene ratios and low values for high resin-to-asphaltene ratios. This is expected to throw light on the cause of the enhanced stability of water-in-crude oil emulsions. 相似文献
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The LiBr assisted/acid catalyzed transacetalation of triols from DMM affords a highly selective method for the synthesis of hydroxy compounds bearing a dioxane ring. These compounds might further conveniently be alkylated by phase transfer catalyzis. 相似文献
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Khan KM Saify ZS Begum S Noor F Khan MZ Hayat S Choudhary MI Perveen S Atta-Ur-Rahman Zia-Ullah 《Natural product research》2003,17(2):115-125
7-Hydroxy-4-methyl-2H-chromen-2-one (2), 7-hydroxy-4,5-dimethyl-2H-chromen-2-one (15) and their some derivatives were synthesized for exploring selected biological screening. The compounds 9 and 13 had shown high degree of cytotoxic activity. Three compound 9, 10 and 13 showed high degree of bactericidal activity amongst the present series. 相似文献