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作者：Alpern, Steve; Lidbetter, Thomas
作者单位：University of Warwick; University of London; London School Economics & Political Science
摘要：We show how to optimize the search for a hidden object, terrorist, or simply Hider, located at a point H according to a known or unknown distribution v on a rooted network Q. We modify the traditional pathwise search approach to a more general notion of expanding search. When the Hider is restricted to the nodes of Q, an expanding search S consists of an ordering (a(1), a(2), ... ) of the arcs of a spanning subtree such that the root node is in a(1) and every arc a(i) is adjacent to a previous...
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作者：Baldacci, Roberto; Mingozzi, Aristide; Roberti, Roberto; Clavo, Roberto Wolfler
作者单位：University of Bologna; University of Bologna; Universite Paris 13; Centre National de la Recherche Scientifique (CNRS); CNRS - Institute of Physics (INP)
摘要：In the two-echelon capacitated vehicle routing problem (2E-CVRP), the delivery to customers from a depot uses intermediate depots, called satellites. The 2E-CVRP involves two levels of routing problems. The first level requires a design of the routes for a vehicle fleet located at the depot to transport the customer demands to a subset of the satellites. The second level concerns the routing of a vehicle fleet located at the satellites to serve all customers from the satellites supplied from t...
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作者：Carlsson, John Gunnar; Jia, Fan
作者单位：University of Minnesota System; University of Minnesota Twin Cities
摘要：The hub-and-spoke distribution paradigm has been a fundamental principle in geographic network design for more than 40 years. One of the primary advantages that such networks possess is their ability to exploit economies of scale in transportation by aggregating network flows through common sources. In this paper, we consider the problem of designing an optimal hub-and-spoke network in continuous Euclidean space: the spokes of the network are distributed uniformly over a service region, and ou...
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作者：He, Ying; Dyer, James S.; Butler, John C.
作者单位：City University of Hong Kong; University of Texas System; University of Texas Austin; University of Texas System; University of Texas Austin
摘要：We propose a preference condition called shifted difference independence to axiomatize a general habit formation and satiation model (GHS). This model allows for a general habit formation and satiation function that contain many functional forms in the literature as special cases. Since the GHS model can be reduced to either a general satiation model (GSa) or a general habit formation model (GHa), our theory also provides approaches to axiomatize both the GSa model and the GHa model. Furthermo...
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作者：Gounaris, Chrysanthos E.; Wiesemann, Wolfram; Floudas, Christodoulos A.
作者单位：Princeton University; Imperial College London; Princeton University
摘要：The robust capacitated vehicle routing problem (CVRP) under demand uncertainty is studied to address the minimum cost delivery of a product to geographically dispersed customers using capacity-constrained vehicles. Contrary to the deterministic CVRP, which postulates that the customer demands for the product are deterministic and known, the robust CVRP models the customer demands as random variables, and it determines a minimum cost delivery plan that is feasible for all anticipated demand rea...
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作者：Kim, Michael Jong; Makis, Viliam
作者单位：University of Toronto; National University of Singapore
摘要：Stochastic control problems that arise in reliability and maintenance optimization typically assume that information used for decision-making is obtained according to a predetermined sampling schedule. In many real applications, however, there is a high sampling cost associated with collecting such data. It is therefore of equal importance to determine when information should be collected and to decide how this information should be utilized for maintenance decision-making. This type of joint ...
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作者：Agarwal, Yogesh
作者单位：Indian Institute of Management (IIM System); Indian Institute of Management Lucknow
摘要：This paper considers the problem of designing a multicommodity network with single facility type subject to the requirement that under failure of any single edge, the network should permit a feasible flow of all traffic. We study the polyhedral structure of the problem by considering the multigraph obtained by shrinking the nodes, but not the edges, in a k-partition of the original graph. A key theorem is proved according to which a facet of the k-node problem defined on the multigraph resulti...
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作者：Long, Jiancheng; Huang, Hai-Jun; Gao, Ziyou; Szeto, W. Y.
作者单位：Hefei University of Technology; Beihang University; Beijing Jiaotong University; University of Hong Kong
摘要：In this paper a novel variational inequality (VI) formulation of the dynamic user optimal (DUO) route choice problem is proposed using the concept of approach proportion. An approach proportion represents the proportion of travelers that select a turning or through movement when leaving a node. Approach proportions contain travelers' route information so that the realistic effects of physical queues can be captured in a formulation when a physical-queue traffic flow model is adopted, and so th...
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作者：Allon, Gad; Deo, Sarang; Lin, Wuqin
作者单位：Northwestern University; Indian School of Business (ISB)
摘要：In recent years, growth in the demand for emergency medical services, along with decline in the number of hospitals with emergency departments (EDs), has raised concerns about the ability of the EDs to provide adequate service. Many EDs frequently report periods of overcrowding during which they are forced to divert incoming ambulances to neighboring hospitals, a phenomenon known as ambulance diversion. The objective of this paper is to study the impact of key operational characteristics of th...
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作者：Moreno-Centeno, Erick; Karp, Richard M.
作者单位：Texas A&M University System; Texas A&M University College Station; University of California System; University of California Berkeley
摘要：We develop a novel framework, the implicit hitting set approach, for solving a class of combinatorial optimization problems. The explicit hitting set problem is as follows: given a set U and a family S of subsets of U, find a minimum-cardinality set that intersects (hits) every set in S. In the implicit hitting set problem (IHSP), the family of subsets S is not explicitly listed (its size is, generally, exponential in terms of the size of U); instead, it is given via a polynomial-time oracle t...
