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作者：Lin, KY; Ross, SM
作者单位：Virginia Polytechnic Institute & State University; University of California System; University of California Berkeley
摘要：We consider a multiple-server loss model where customers arrive at a gatekeeper according to a Poisson process. A cost c is incurred if a new arrival is blocked from entering the system by the gatekeeper, while a larger cost K is incurred if an admitted customer finds all servers busy and therefore has to leave the system. The key assumption is that the gatekeeper is informed when an admitted customer finds all servers busy, but is not informed when served customers depart. Assuming an exponen...
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作者：Ghamlouche, I; Crainic, TG; Gendreau, M
作者单位：Universite de Montreal; Universite de Montreal; University of Quebec; University of Quebec Montreal; Universite de Montreal
摘要：we propose new cycle-based neighbourhood structures for metaheuristics aimed at the fixed-charge capacitated multicommodity network design formulation. The neighbourhood defines moves that explicitly take into account the impact on the total design cost of potential modifications to the flow distribution of several commodities simultaneously. Moves are identified through a shortest-pathlike network optimization procedure and proceed by redirecting flow around cycles and closing and opening des...
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作者：Lim, WS; Ou, JH; Teo, CP
作者单位：National University of Singapore; National University of Singapore
摘要：Consolidation of warehouses is a new trend in global logistics management, and the reduction in order processing and inventory costs is often cited as one of the main motivations. In this note we show that when retailers face constant demand rates and their ordering costs are independent of the warehouse that services them, consolidated systems are rarely suboptimal and always lead to close-to-optimal inventory replenishment costs. In particular, we prove that using two (one) properly selected...
