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21.
Capacity Constrained Transit Assignment with Common Lines 总被引:1,自引:0,他引:1
Fumitaka Kurauchi Michael G. H. Bell Jan-Dirk Schmöcker 《Journal of Mathematical Modelling and Algorithms》2003,2(4):309-327
This paper proposes the use of absorbing Markov chains to solve the capacity constrained transit network loading problem taking
common lines into account. The approach handles congested transit networks, where some passengers will not be able to board
because of the absence of sufficient space. The model also handles the common lines problem, where choice of route depends
on frequency of arrivals. The mathematical formulation of the problem is presented together with a numerical example.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
22.
Maria G. Semenova Larisa E. Belyakova Anna S. Antipova Yu. N. Polikarpov Lida Klouda Anna Markovic Michael M. Il'in 《Colloids and surfaces. B, Biointerfaces》2003,31(1-4):47-54
We report on the effect of commercially important polysaccharides (maltodextrins with variable dextrose equivalent (Paselli SA-2, MD-6 and MD-10) on the surface activity at the air–water interface of small-molecule surfactants (sms), possessing different hydrophobic–lipophilic balance ((SSL (Na+), the main component is a sodium salt of stearol–lactoyl lactic acid, and PGE (080), polyglycerol ester of C18 fatty acid), and widely used in food products. A marked change of the surface activity of sms was found in the presence of maltodextrins by tensiometry. The combined data of laser multiangle light scattering and mixing calorimetry have suggested that this result is governed by specific complex formation between maltodextrins and sms in aqueous medium. Measurements have been made of the molar mass, the second virial coefficient and the enthalpy of intermolecular interactions in aqueous solutions. The implication of a degree of polymerization of maltodextrins in this phenomenon was shown. The interrelation between the molecular parameters of the formed complexes and their surface activity at the air–water interface has been revealed and discussed. 相似文献
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Michael B. Mensky 《General Relativity and Gravitation》2003,35(9):1729-1732
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Michael S. Roddy 《Order》1994,11(1):1-9
Theretracts (idempotent, isotone self-maps) of an ordered set are naturally ordered as functions. In this note we characterize the possible ways that one retract can cover another one. This gives some insight into the structure of the ordered set of retracts and leads to a natural generalization of the core of an ordered set.Supported by NSERC Operating Grant 41702. 相似文献
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In previous work the authors consider the dynamic assignment problem, which involves solving sequences of assignment problems over time in the presence of uncertain information about the future. The algorithm proposed by the authors provides generally high-quality but non-optimal solutions. In this work, though, the authors prove that if the optimal solution to a dynamic assignment problem in one of two problem classes is unique, then the optimal solution is a fixed point under the algorithm. 相似文献