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作者：Zhu, Endong; Crainic, Teodor Gabriel; Gendreau, Michel
作者单位：University of Quebec; University of Quebec Montreal; Universite de Montreal; University of Quebec; University of Quebec Montreal; Universite de Montreal; Polytechnique Montreal; Universite de Montreal; Polytechnique Montreal
摘要：This paper addresses the scheduled service network design problem for freight rail transportation. The proposed model integrates service selection and scheduling, car classification and blocking, train makeup, and routing of time-dependent customer shipments based on a cyclic three-layer space-time network representation of the associated operations and decisions and their relations and time dimensions. This paper also proposes a matheuristic solution methodology integrating slope scaling, a d...
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作者：Zaghrouti, Abdelouahab; Soumis, Francois; El Hallaoui, Issmail
作者单位：Universite de Montreal; Universite de Montreal; Polytechnique Montreal
摘要：Since the 1970s, several authors have studied the structure of the set partitioning polytope and proposed adaptations of the simplex algorithm that find an optimal solution via a sequence of basic integer solutions. Balas and Padberg in 1972 proved the existence of such a sequence with nonincreasing costs, but degeneracy makes it difficult to find the terms of the sequence. This paper uses ideas from the improved primal simplex to deal efficiently with degeneracy and find subsequent terms in t...
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作者：Chen, Xin; Pang, Zhan; Pan, Limeng
作者单位：Nanjing University; University of Illinois System; University of Illinois Urbana-Champaign; Lancaster University
摘要：We analyze a joint pricing and inventory control problem for a perishable product with a fixed lifetime over a finite horizon. In each period, demand depends on the price of the current period plus an additive random term. Inventories can be intentionally disposed of, and those that reach their lifetime have to be disposed of. The objective is to find a joint pricing, ordering, and disposal policy to maximize the total expected discounted profit over the planning horizon taking into account li...
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作者：Nikolova, E.; Stier-Moses, N. E.
作者单位：University of Texas System; University of Texas Austin; Texas A&M University System; Texas A&M University College Station; Columbia University; Universidad Torcuato Di Tella; Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET)
摘要：Heavy and uncertain traffic conditions exacerbate the commuting experience of millions of people across the globe. When planning important trips, commuters typically add an extra buffer to the expected trip duration to ensure on-time arrival. Motivated by this, we propose a new traffic assignment model that takes into account the stochastic nature of travel times. Our model extends the traditional model of Wardrop competition when uncertainty is present in the network. The focus is on strategi...
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作者：Davis, James M.; Gallego, Guillermo; Topaloglu, Huseyin
作者单位：Cornell University; Columbia University
摘要：We study a class of assortment optimization problems where customers choose among the offered products according to the nested logit model. There is a fixed revenue associated with each product. The objective is to find an assortment of products to offer so as to maximize the expected revenue per customer. We show that the problem is polynomially solvable when the nest dissimilarity parameters of the choice model are less than one and the customers always make a purchase within the selected ne...
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作者：Cavus, Ozlem; Ruszczynski, Andrzej
作者单位：Ihsan Dogramaci Bilkent University; Rutgers University System; Rutgers University New Brunswick
摘要：The total cost problem for discrete-time controlled transient Markov models is considered. The objective functional is a Markov dynamic risk measure of the total cost. Two solution methods, value and policy iteration, are proposed, and their convergence is analyzed. In the policy iteration method, we propose two algorithms for policy evaluation: the nonsmooth Newton method and convex programming, and we prove their convergence. The results are illustrated on a credit limit control problem.
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作者：Chou, Mabel C.; Chua, Geoffrey A.; Zheng, Huan
作者单位：National University of Singapore; Nanyang Technological University; Shanghai Jiao Tong University
摘要：Production postponement, the strategy to hold reserved production capacity that can be deployed based on actual demand signals, is often used to mitigate supply-demand mismatch risk. The effectiveness of this strategy depends crucially on the ease, or flexibility, in deploying the reserved capacity to meet product demands. Existing literature assumes that the reserved capacity is fully flexible, i.e., capable of being deployed to meet the demand of any item in a multiproduct system. Little is ...
