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241.
This article describes an algorithm for solving the static electric utility capacity expansion problem. The advantages of this algorithm are twofold. First, it is simpler and yet more efficient than previous algorithms for the same problem. Second, by making simplifying but realistic assumptions on plant sizes it is possible to use this algorithm for the case where one does not allow fractional plant additions. While the model has n variables, it has a clear two-dimensional geometric representation for understanding its properties, developing an algorithm, and interpreting the optimal solution. This algorithm has been implemented in the Intermediate Future Forecasting (IFFS) capacity expansion model at the Department of Energy.  相似文献   
242.
How do we understand combat effectiveness – soldiers’ performance in battle? Despite the broad consensus that understanding combat effectiveness is important both for scholars and policymakers, there is widespread disagreement about what combat effectiveness is. More specifically, studies of effectiveness tend to focus on either the skill of soldiers in battle, or their will to fight. Yet both skill and will are essential components of an effective fighting force. This article argues that understanding combat effectiveness requires understanding both of these key components of effectiveness. In other words, combat effectiveness requires both the skill and will to engage the enemy in an organized manner. It then demonstrates the usefulness of this conceptualization by applying it to the cases of British, Indian, and Australian forces fighting the Japanese during the Second World War. Only when scholars are talking about the same concept will our understanding of the conditions under which militaries are effective in battle progress. By comparing different units fighting the same opponent under the same material conditions, I demonstrate that units vary both in their combat skill and their will to fight, and that understanding their effectiveness in battle requires analyzing both of these key factors.  相似文献   
243.
Abstract

The U.S. Department of Defense (DoD) and the U.S. Department of Veterans Affairs (VA) need to bridge a gap in their understanding of service members’ health outcomes and the issues involved in treatment, such as cost. In addition, clinicians and policy analysts must overcome existing knowledge barriers. Clinicians need to be aware of policy changes that will affect their patient load in numbers and in treatment needs. Policy analysts need to be aware of issues relevant to clinical treatment, such as quality and timeliness of care. Given the need for services and support to military personnel and families, and the fact that the fastest growing expenses in defense are health care costs, a multi-disciplinary line of research will help lawmakers understand the most efficient and effective resource use across the health care services.  相似文献   
244.
This article addresses the problem of scheduling the United States Navy's Atlantic Fleet to satisfy overseas strategic requirements. An integer programming formulation is developed but results in a model with prohibitive size. This fact and the qualitative nature of additional secondary objectives and constraints suggest an interactive optimization approach. A system that solves a natural relaxation of the integer program within an interactive environment is discussed.  相似文献   
245.
针对ATML标准中诊断信息描述一致性问题,提出了基于STEP的AI—ESTATE数据类型转换方法。首先介绍了ATML中诊断信息的描述标准,其次分析了AI—ESTATE信息描述的转换方法,然后应用STEP28针对CEM存在的数据类型进行了EXPRESS-XML匹配结构和功能结构一致性研究,最后建立了CEM典型数据类型的XML标准化描述。  相似文献   
246.
247.
A unified treatment is given for a class of discrete distributions derived by compounding a bivariate Poisson with a bivariate discrete or continuous distribution. Using generating functions a number of interesting results are obtained for probabilities, moments, cumulants, factorial moments, and factorial cumulants. Conditional distributions and regression functions are also examined. Five illustrative examples are presented in detail. © 1994 John Wiley & Sons, Inc.  相似文献   
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249.
The minimum makespan of the general parallel machine scheduling problem with m machines and n jobs is studied. As for a number of other important combinatorial problems, the theory of empirical processes proves to be a very elegant and powerful tool for the probabilistic analysis of the solution value. It is used in this paper to derive a scheduling constant θ such that, for random processing times, the minimum makespan almost surely grows as θn when n goes to infinity. Moreover, a thorough probabilistic analysis is performed on the difference between the minimum makespan and θn. Explicit expressions for the scheduling constant are given for an arbitrary number of unrelated machines with identically distributed processing times (with an increasing failure rate), and for an arbitrary number of uniform machines and generally distributed processing times. © 1996 John Wiley & Sons, Inc.  相似文献   
250.
The bivariate negative binomial distribution of Mitchell and Paulson [17] for the case b = c = 0 is shown to be equivalent to the accident proneness model of Edwards and Gurland [4] and Subrahmaniam [19,20]. The diagonal series expansion of its joint probability function is then derived. Two other formulations of this distribution are also considered: (i) as a mixture model, which showed how it arises as the discrete analogue to the Wicksell-Kibble bivariate gamma distribution, and (ii) as a consequence of the linear birth-and-death process with immigration.  相似文献   
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