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101.
The problem of assigning computer program modules to functionally similar processors in a distributed computer network is investigated. The modules of a program must be assigned among processors in such a way as to minimize interprocessor communication while taking advantage of affinities of certain modules to particular processors. This problem is formulated as a zero-one quadratic programming problem, but is more conveniently modeled as a directed acyclic search graph. The model is developed and a backward shortest path labeling algorithm is given that produces an assignment of program modules to processors. A non-backtracking branch-and-bound algorithm is described that uses a local neighborhood search at each stage of the search graph. 相似文献
102.
The paper presents the formulation and several solutions of a model for allocating a fixed number of aircraft to carriers and to missions. The amount of damage that can be inflicted is maximized. A nonseparable concave nonlinear objective function expresses diminishing marginal damage. Linear constraints on aireraft, carrier space, and aircraft availability for missions are included. The model is solved using the sequential unconstrained minimization technique (SUMT). The model is presented in terms of a scenario. Several different exponential damage functions are treated, and S-shaped damage functions are discussed. 相似文献
103.
Several approximate procedures are available in the literature for obtaining confidence intervals for the parameter A of an exponential distribution based on time truncated samples. This paper contains the results of an empirical study comparing three of these procedures. 相似文献
104.
If international terrorism is on a rising trend, an important source of confirmation or refutation of this is time‐series data on terrorist activity. Using chiefly data collected by the RAND/MIPT consortium we show using basic statistical analysis that in the period 1968–2005 the yearly number of all international terrorist incidents shows no trend over time, but fluctuates year on year in a random manner. On the other hand some indicators do show a definite trend over time, principally the steady rise in the number of incidents that are death‐dealing in nature. A further conclusion is drawn, showing that the proportion of these incidents leading to deaths above a given level is virtually fixed. 相似文献
105.
106.
Dinah W. Cheng 《海军后勤学研究》1994,41(6):759-770
We demonstrate here how recent advances in the study of discrete-event stochastic systems provide fruitful results for the modeling, analysis, and design of manufacturing systems. We consider a multistage make-to-stock system where outputs from the final stage are used to satisfy customer demands. We address the problem of finding the appropriate trade-off between reduced order waiting time and increased process speeds. Using the idea of infinitesimal perturbation analysis (IPA), we establish a simple procedure where sample-path derivatives can be obtained along an arbitrary sample path. Under suitable conditions, we demonstrate that these derivative estimators are unbiased and strongly consistent and can be used in a classical stochastic optimization scheme to solve the problem. The role of continuity and convexity on the validity of the estimator is also addressed. Although the focus of this article is not to solve for the optimal solution, we provide a theoretical justification for such a pursuit. The approach is appealing as it is numerically stable, easy to implement, and can be extended to other system performance measures. © 1994 John Wiley & Sons, Inc. 相似文献
107.
The verification of arms-control and disarmament agreements requires states to provide declarations, including information on sensitive military sites and assets. There are important cases, however, in which negotiations of these agreements are impeded because states are reluctant to provide any such data, because of concerns about prematurely handing over militarily significant information. To address this challenge, we present a cryptographic escrow that allows a state to make a complete declaration of sites and assets at the outset and commit to its content, but only reveal the sensitive information therein sequentially. Combined with an inspection regime, our escrow allows for step-by-step verification of the correctness and completeness of the initial declaration so that the information release and inspections keep pace with parallel diplomatic and political processes. We apply this approach to the possible denuclearization of North Korea. Such approach can be applied, however, to any agreement requiring the sharing of sensitive information. 相似文献
108.
Clifford W. Marshall 《海军后勤学研究》1969,16(4):531-541
This paper presents a quantitative index of the level of risk assumed by a contractor in various contract type situations. The definition includes expression of real world uncertainty and contractor's utility for money. Examples are given for the major contract types and special applications are discussed. 相似文献
109.
Richard B. Streeter Guy W. Hagen Edward E. Patenaude Dennis K. Killinger 《Defence and Peace Economics》2013,24(6):569-587
This paper presents a model for converting legacy defense production facilities into private‐sector economic resources. Specifically, this paper will examine as a case study the first successful conversion of a former U.S. Department of Energy nuclear weapons production installation, including reasons for its success, its costs and benefits, and lessons for public policy. It is envisioned that this model may be useful for mitigating local economic hardship resulting from defense “downsizing” and for privatizing production capacities critical for national defense. 相似文献
110.
Daniel Khalessi 《The Nonproliferation Review》2013,20(3-4):421-439
ABSTRACTSince the 1950s, the United States has engaged in nuclear sharing with its NATO allies. Today, 150-200 tactical nuclear weapons remain on European soil. However, the Treaty on the Non-proliferation of Nuclear Weapons (NPT) prohibits the transfer of nuclear weapons to non-nuclear weapon states. The potential discrepancy between text and practice raises the question of how the NPT's negotiators dealt with NATO's nuclear-sharing arrangements while drafting the treaty that would eventually become the bedrock of the international nonproliferation regime. Using a multitiered analysis of secret negotiations within the White House National Security Council, NATO, and US-Soviet bilateral meetings, this article finds that NATO's nuclear-sharing arrangements strengthened the NPT in the short term by lowering West German incentives to build the bomb. However, this article also finds that decision makers and negotiators in the Lyndon B. Johnson administration had a coordinated strategy of deliberately inserting ambiguous language into drafts of Articles I and II of the Treaty to protect and preserve NATO's pre-existing nuclear-sharing arrangements in Europe. This diplomatic approach by the Johnson administration offers lessons for challenges concerning NATO and relations with Russia today. 相似文献