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41.
In this article we investigate situations where the buyer is offered discounted price schedules from alternative vendors. Given various discount schedules, the buyer must make the best buying decision under a variety of constraints, such as limited storage space and restricted inventory budgets. Solutions to this problem can be utilized by the buyer to improve profitability. EOQ models for multiple products with all-units discounts are readily solvable in the absence of constraints spanning the products. However, constrained discounted EOQ models lack convenient mathematical properties. Relaxing the product-spanning constraints produces a dual problem that is separable, but lack of convexity and smoothness opens the door for duality gaps. In this research we present a set of algorithms that collectively find the optimal order vector. Finally, we present numerical examples using actual data. to illustrate the application of the algorithms. © 1993 John Wiley & Sons, Inc.  相似文献   
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Using the general computational strategy of restriction, necessary conditions for optimality provide an alternative criterion for entering variables when degeneracies arises in linear programming problems. Although cycling may still occur, it is shown that if it is possible to make progress at the next iteration, the criterion is guaranteed to identify a non-basic variable which increases the value of the basic solution, thereby reducing stalling. An alternative method for determining variables to exit the basis when degeneracies occur is also suggested.  相似文献   
44.
We show the existence of a unique analytic single parameter limiting survival function arising from the repeated composition of a coherent structure as the number of components tends to infinity. Examples include the repeated composition process of the bridge structure. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004.  相似文献   
45.
Chen and Bhattacharyya [Exact confidence bounds for an exponential parameter under hybrid censoring, Commun Statist Theory Methods 17 (1988), 1857–1870] considered a hybrid censoring scheme and obtained the exact distribution of the maximum likelihood estimator of the mean of an exponential distribution along with an exact lower confidence bound. Childs et al. [Exact likelihood inference based on Type‐I and Type‐II hybrid censored samples from the exponential distribution, Ann Inst Statist Math 55 (2003), 319–330] recently derived an alternative simpler expression for the distribution of the MLE. These authors also proposed a new hybrid censoring scheme and derived similar results for the exponential model. In this paper, we propose two generalized hybrid censoring schemes which have some advantages over the hybrid censoring schemes already discussed in the literature. We then derive the exact distribution of the maximum likelihood estimator as well as exact confidence intervals for the mean of the exponential distribution under these generalized hybrid censoring schemes. © 2004 Wiley Periodicals, Inc. Naval Research Logistics, 2004  相似文献   
46.
Book Reviews     
Patrick Finney (ed.), The Origins of the Second World War. London: Arnold, 1997. Pp.xvi + 461, index. £15.99. ISBN 0–340–67640‐X.

Maria Emilia Paz, Strategy, Security, and Spies: Mexico and the US as Allies in World War II. University Park, PA: The Pennsylvania State University Press, 1997. Pp.xii + 264, 10 illus., biblio., index. $55 (cloth); $19.95 (paper). ISBN 0–271–01665–5 and 01666–3.

Norman J.W. Goda, Tomorrow the World: Hitler, Northwest Africa and the Path toward America. College Station, Texas A&;M University Press, 1998. Pp.xxvi + 307, 2 maps, biblio., index. $39.95. ISBN 0–89096–807–1.

Michael J. Hogan, A Cross of Iron: Harry S. Truman and the Origins of the National Security State, 1945–1954. Cambridge; New York: Cambridge University Press, 1998. Pp.xii + 525, biblio., index. £25; $34.95. ISBN 0–521–64044‐X.

Stephen Van Evera, Causes of War: Power and the Roots of Conflict. Ithaca, NY: Cornell University Press, 1999. Pp.viii + 270, index. $35. ISBN 0–801403201–4.

Eric Arnett (ed.), Nuclear Weapons and Arms Control in South Asia after the Test Ban, SIPRI Research Report No.14. Oxford: Oxford University Press/Stockholm Int Peace Research Institute, 1998. Pp.viii + 98, index. £12.99. ISBN 0–19–8294115.

T.V. Paul, Richard J. Harknett and James J. Wirtz (eds.), The Absolute Weapon Revisited: Nuclear Arms and Emerging International Order. Ann Arbor, Michigan: The University of Michigan Press, 1998. Pp.vi + 312, index. $47.50/£36. ISBN 0–472–10863–8.  相似文献   
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Stochastic combat models are more realistic than either deterministic or exponential models. Stochastic combat models have been solved analytically only for small combat sizes. It is very difficult, if not impossible, to extend previous solution techniques to larger-scale combat. This research provides the solution for many-on-many heterogeneous stochastic combat with any break points. Furthermore, every stage in stochastic combat is clearly defined and associated aiming and killing probabilities are calculated. © 1996 John Wiley & Sons, Inc.  相似文献   
49.
Silverman's game on (1, B) × (1, B) was analyzed by R. J. Evans, who showed that optimal strategies exist (and found them) only on a set of measure zero in the parameter plane. We examine the corresponding game on (1, B) × (1, D) with D > B, and show that optimal strategies exist in about half the parameter plane. Optimal strategies and game value are obtained explicitly. © 1995 John Wiley & Sons, Inc.  相似文献   
50.
This article introduces the use of Benders' cuts to guide a large neighborhood search to solve the traveling umpire problem, a sports scheduling problem inspired by the real‐life needs of the officials of a sports league. At each time slot, a greedy matching heuristic is used to construct a schedule. When an infeasibility is recognized first a single step backtracking is tried to resolve the infeasibility. If unsuccessful, Benders' cuts are generated to guide a large neighborhood search to ensure feasibility and to improve the solution. Realizing the inherent symmetry present in the problem, a large family of cuts are generated and their effectiveness is tested. The resulting approach is able to find better solutions to many instances of this problem. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011  相似文献   
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