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作者：KRAAY, D; HARKER, PT; CHEN, BT
摘要：Recent developments in location systems technology for railroads provide a train dispatcher with the capability to improve the operations of a rail line by pacing trains over a territory; i.e., to permit trains to travel at less than maximum velocity to minimize fuel consumption while maintaining a given level of performance. Traditional railroad dispatching models assume that the velocities of the trains moving over a dispatcher's territory are fixed at their maximum value and, thus, are inca...
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作者：HOOKER, JN; GARFINKEL, RS; CHEN, CK
作者单位：University of Connecticut
摘要：A research theme involving location on networks, since its inception, has been the identification of a finite dominating set (FDS), or a finite set of points to which an optimal solution must belong. We attempt to unify and generalize results of this sort. We survey the literature and then prove some theorems that subsume most previous results and that are, at the same time, more genral than previous results. The paper is aimed primarily at investigators who wish to know whether an FDS exists ...
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作者：PREKOPA, A; BOROS, E
摘要：Many transportation networks, e.g., networks of cooperating power systems, and hydrological networks involve a real-valued demand function, defined on the set of nodes, and it is said to be feasible if there exists a flow such that at each node the sum of the incoming flow values is greater than or equal to the demand assigned to this node. By the theorem of D. Gale and A. Hoffman, a system of linear inequalities involving the demand and the arc capacity functions, gives necessary and sufficie...
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作者：ANILY, S; FEDERGRUEN, A
作者单位：Tel Aviv University; Columbia University
摘要：In many important combinatorial optimization problems, such as bin packing, allocating customer classes to queueing facilities, vehicle routing, multi-item inventory replenishment and combined routing/inventory control, an optimal partition into groups needs to be determined for a finite collection of objects; each is characterized by a single attribute. The cost is often separable in the groups and the group cost often depends on the cardinality and some aggregate measure of the attributes, s...
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作者：BALAS, E; SALTZMAN, MJ
作者单位：Clemson University
摘要：We describe a branch-and-bound algorithm for solving the axial three-index assignment problem. The main features of the algorithm include a Lagrangian relaxation that incorporates a class of facet inequalities and is solved by a modified subgradient procedure to find good lower bounds, a primal heuristic based on the principle of minimizing maximum regret plus a variable depth interchange phase for finding good upper bounds, and a novel branching strategy that exploits problem structure to fix...
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作者：LOVEJOY, WS
摘要：A partially observed Markov decision process (POMDP) is a sequential decision problem where information concerning parameters of interest is incomplete, and possible actions include sampling, surveying, or otherwise collecting additional information. Such problems can theoretically be solved as dynamic programs, but the relevant state space is infinite, which inhibits algorithmic solution. This paper explains how to approximate the state space by a finite grid of points, and use that grid to c...
