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651.
This article presents a branch and bound method for solving the problem of minimizing a separable concave function over a convex polyhedral set where the variables are restricted to be integer valued. Computational results are reported.  相似文献   
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Book reviews     
Die Faszination des Verrats: Eine Studie zur Dekadenz im Ost‐West Konflikt. By Thomas Noetzel. Hamburg, Junius (1989) DM48.

Les Nations Armées. By Maurice Faivre (Preface by Pierre Messmer), Paris FEDN/Economica (1988).

Insurgency and Terrorism: Inside Modern Revolutionary Warfare. By Bard E. O'Neill, Brassey's (US), Washington, DC (1990), $19.00.

LIC 2010: Special Operations and Unconventional Warfare in the Next Century. By Rod Paschall, Brassey's (US), Washington, DC, $24.00.

Air Power and Colonial Conflict: The Royal Air Force 1919–1939. By D. E. Omissi, Manchester University Press, Manchester and New York (1990), ISBN 0–7190–2960–0. £35.00.

Key to the Sinai: The Battles for Abu Ageila in the 1956 and 1967 Arab‐Israeli Wars. By George W. Gawrych. Combat Studies Institute Research Survey No. 7, US Army Command and General Staff College, Fort Leavenworth, Kansas, 1990. $8.00.

Arms Export Regulations. Edited by Ian Anthony. SIPRI/Oxford University Press, Oxford (1991), ISBN 0–19–829158–2, £25.00.  相似文献   

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A large population of independent identical units having finite mean lifetime T is observed. From the history A(y) of cumulative arrivals and the history B(y) of cumulative removals in the interval 0 ≦ y ≦ τ one must predict at time τ the desired T . Two lifetime predictors X(τ) and Y(τ) and related simple predictors obtained from A(y) and B(y) are shown to converge to T with a rate of convergence dependent on the structure of the failure rate function of the units. This dependence is studied theoretically and numerically.  相似文献   
658.
In this article, we describe a new algorithm for solving all-integer, integer programming problems. We generate upper bounds on the decision variables, and use these bounds to create an advanced starting point for a dual all-integer cutting plane algorithm. In addition, we use a constraint derived from the objective function to speed progress toward the optimal solution. Our basic vehicle is the dual all-integer algorithm of Gomory, but we incorporate certain row- and column-selection criteria which partially avoid the problem of dual-degenerate iterations. We present the results of computational testing.  相似文献   
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This paper investigates the effect of the optimal solution of a (capacitated) generalized transportation problem when the data of the problem (the rim conditions—i.e., the available time of machine types and demands of product types, the per unit production costs, the per unit production time and the upper bounds) are continuously varied as a linear function of a single parameter. Operators that effect the transformation of optimal solution associated with such data changes, are shown to be a product of basis preserving operators (described in our earlier papers) that operate on a sequence of adjacent basis structures. Algorithms are furnished for the three types of operators—rim, cost, and weight. The paper concludes with a discussion of the production and managerial interpretations of the operators and a comment on the “production paradox”.  相似文献   
660.
Structured finite action-finite state space discounted Markovian decision problems are analyzed. Any problem of a general class is shown to be equivalent to a “separated” problem with decomposable problem structure. A modified policy iteration approach is developed for this decomposable reformulation. Both analytic and computer evaluations of the decomposition algorithm's effectiveness are presented.  相似文献   
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