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371.
In recent years military procurement agencies have used “progress payments” in contracting. Although, overall, the adoption of such a policy may well have contributed to a decrease in total costs of procurement, we identify a class of inefficiencies that are likely to have been generated by it.  相似文献   
372.
For a three‐sector Feder‐Ram framework, we present time‐series, cross‐sectional estimates for two cohorts, consisting of Asian and Latin American countries. The estimates indicate that private investment, and defense and non‐defense public spending are growth promoting for alternative error components representations. For the best error components representation, greater growth enhancement is associated with the two forms of public spending in Asia than in Latin America, while the opposite comparison characterizes private investment. Although defense is growth promoting, an opportunity cost exists insofar as non‐defense spending, financed by defense spending, appears to give a small net boost to growth in Latin America.  相似文献   
373.
CONTRIBUTORS     
Russia holds the largest stocks of civilian highly enriched uranium (HEU) of any country, operating more than fifty research reactors, pulsed reactors, and critical assemblies using HEU, as well as nine HEU-fueled icebreakers. Russia's participation in international efforts to phase out civilian HEU is crucial if international HEU minimization efforts are to succeed. Individual Russian institutes and organizations participate in international programs to replace HEU with low-enriched uranium in Soviet-supplied research reactors, develop alternative fuels, and repatriate fresh and spent HEU fuel from third countries. However, an overarching national policy on HEU phase-out has yet to be adopted. There are many obstacles to obtaining such a commitment from Moscow. At the same time, the ongoing reform of the Russian nuclear industry and plans for expansion of domestic nuclear power generation and for increased nuclear exports create opportunities for securing such a commitment.  相似文献   
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Accelerated life testing (ALT) is commonly used to obtain reliability information about a product in a timely manner. Several stress loading designs have been proposed and recent research interests have emerged concerning the development of equivalent ALT plans. Step‐stress ALT (SSALT) is one of the most commonly used stress loadings because it usually shortens the test duration and reduces the number of required test units. This article considers two fundamental questions when designing a SSALT and provides formal proofs in answer to each. Namely: (1) can a simple SSALT be designed so that it is equivalent to other stress loading designs? (2) when optimizing a multilevel SSALT, does it degenerate to a simple SSALT plan? The answers to both queries, under certain reasonable model assumptions, are shown to be a qualified YES. In addition, we provide an argument to support the rationale of a common practice in designing a SSALT, that is, setting the higher stress level as high as possible in a SSALT plan. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
376.
In this article, we study deterministic dynamic lot‐sizing problems with a service‐level constraint on the total number of periods in which backlogs can occur over a finite planning horizon. We give a natural mixed integer programming formulation for the single item problem (LS‐SL‐I) and study the structure of its solution. We show that an optimal solution to this problem can be found in \begin{align*}\mathcal O(n^2\kappa)\end{align*} time, where n is the planning horizon and \begin{align*}\kappa=\mathcal O(n)\end{align*} is the maximum number of periods in which demand can be backlogged. Using the proposed shortest path algorithms, we develop alternative tight extended formulations for LS‐SL‐I and one of its relaxations, which we refer to as uncapacitated lot sizing with setups for stocks and backlogs. {We show that this relaxation also appears as a substructure in a lot‐sizing problem which limits the total amount of a period's demand met from a later period, across all periods.} We report computational results that compare the natural and extended formulations on multi‐item service‐level constrained instances. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
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We introduce an optimal stopping problem for selling an asset when the fixed but unknown distribution of successive offers is from one of n possible distributions. The initial probabilities as to which is the true distribution are given and updated in a Bayesian manner as the successive offers are observed. After receiving an offer, the seller has to decide whether to accept the offer or continue to observe the next offer. Each time an offer is observed a fixed cost is incurred. We consider both the cases where recalling a past offer is allowed and where it is not allowed. For each case, a dynamic programming model and some heuristic policies are presented. Using simulation, the performances of the heuristic methods are evaluated and upper bounds on the optimal expected return are obtained. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
380.
Book reviews     
Norman Cigar, Genocide in Bosnia: The Policy of “Ethnic Cleansing”. College Station, Texas: Texas A&M University Press, 1995. Pp.xiv + 247; app., map, notes, cartoon.

Maria Jose Moyano, Argentina's Lost Patrol: Armed Struggle, 1969–1979. New Haven: Connecticut Yale University Press, 1995. Pp.xiii + 226, biblio., abbreviations, 10 figures, 1 map, tables, index; $25/£16.95. ISBN 0–300–01622–6.

Donald E. Schulz and Deborah Sundloff Schulz, The United States, Honduras, and the Crisis in Central America, Westview Thematic Studies in Latin America, Boulder, Co: Westview, 1994. Pp.368, map, figure, select biblio., abbreviations, index. $52.50/£37.50; (cloth) $17.95/£11.95 (paper). ISBN 0–8133–1324–4 and 1323–6.

Joseph H. Alexander and Merrill L. Bartlett, Sea Soldiers in the Cold War: Amphibious Warfare 1945–1991. Annapolis, Maryland: Naval Institute Press, 1995. Pp.iii + 178, 1 map, 29 illus, biblio, index. $32.95. ISBN

Gary P. Cox, The Halt in the Mud: French Strategic Planning from Waterloo to Sedan. Westview Press, 1994. Pp.258, maps, notes, biblio, index. £33.50. ISBN 0–133–1536–0.  相似文献   
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