摘要:

AbstractConsider a central depot that supplies several locations experiencing random demands. Periodically, the depot may place an order for exogenous supply. Orders arrive after a fixed leadtime, and are then allocated among the several locations. Each allocation reaches its destination after a further delay. We consider the special case where the penalty‐cost/holding‐cost ratio is constant over the locations. Several approaches are given to approximate the dynamic program describing the problem. Each approach provides both a near‐optimal order policy and an approximation of the optimal cost of the original problem. In addition, simple but effective allocation policies are disc

ISSN:0028-1441    

DOI:10.1002/nav.3800310112

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractA recent work obtained closed‐form expressions for the problem of optimal partitioning multi‐item inventories into a given number of groups, where each group has a common order cycle for all the items in the group, and a Pareto function characterizes the distributions by value of the inventory. The optimal order points so obtained for the groups may have no synchronization among themselves at all. This note extends the closed‐form analysis to the requirement that the order cycles be coordinated so that each cycle is an integral multiple of the shortest order cycle. The extent of suboptimality which thus follows is investigated. Several alternatives to achieve integrality have been considered and compared through an illustrative example within the framework of the Pareto fun

ISSN:0028-1441    

DOI:10.1002/nav.3800310113

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractAnn‐component parallel system is subjected to a known load program. As time passes, components fail in a random manner, which depends on their individual load histories. At any time, the surviving components share the total load according to some rule. The system's life distribution is studied under the linear breakdown rule and it is shown that if the load program is increasing, the system lifetime is IFR. Using the notion of Schur convexity, a stochastic comparison of different systems is obtained. It is also shown that the system failure time is asymptotically normally distributed as the number of components grows large. All these results hold under various load‐sharing rules; in fact, we show that the system lifetime distribution is invariant under different load‐sharing

ISSN:0028-1441    

DOI:10.1002/nav.3800310114

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractIn this article we present three properties that will improve the performance of branch‐and‐bound algorithms for fixed‐cost transportation problems. By applying Lagrangian relaxation we show that one can develop stronger up and down penalties than those traditionally used and also develop a strengthened penalty for nonbasic variables. We also show that it is possible to “look ahead” of a particular node and determine the solution at the next node without actually calculating it. We present computational evidence by comparing our developments with existing p

ISSN:0028-1441    

DOI:10.1002/nav.3800310115

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractSupposeXis a random variable having an absolutely continuous distribution functionF(x). We assume thatF(x) has the Wald distribution. A relation between the probability density function ofX−1with that ofXis used to characterize the Wald distributio

ISSN:0028-1441    

DOI:10.1002/nav.3800310116

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractThis article demonstrates that whenever the probability of single‐shot kill is nondecreasing (from one salvo to the next), then the sequence of salvo sizes which minimizes the expected number of shots used is also nondecreasin

ISSN:0028-1441    

DOI:10.1002/nav.3800310117

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

摘要:

AbstractA heuristic solution procedure for set covering is presented that works well for large, relatively dense problems. In addition, a confidence interval is established about the unknown global optimum. Results are presented for 30 large randomly generated problems.

ISSN:0028-1441    

DOI:10.1002/nav.3800310118

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY

ISSN:0028-1441    

DOI:10.1002/nav.3800310101

出版商:Wiley Subscription Services, Inc., A Wiley Company    

年代:1984

数据来源: WILEY