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51.
Andrew S. Bowen 《战略研究杂志》2019,42(3-4):312-343
What were Russia’s objectives in Eastern Ukraine, and why was it seemingly unable to achieve a successful or decisive outcome? In contrast to Russia’s seizure of Crimea, the uprising in Eastern Ukraine was marked by disorganization and chaos. Using proxy and surrogate actors, along with military exercises and the injection of Russian troops, Russia sought to institutionalize a political entity inside Ukraine to influence its domestic politics. In this article, I analyze the mechanisms by which Russia attempted to implement, and later salvage, its strategy. The article contributes to clearer theoretical and practical understanding of limited force in coercive diplomacy, signaling, and a more rigorous treatment of the role and uses of proxy actors. 相似文献
52.
Adam D. Bramoweth James Luther Barbara H. Hanusa Jon D. Walker Charles W. Atwood Jr. Anne Germain 《Defence and Peace Economics》2018,29(1):78-90
AbstractInsomnia is prevalent among Veterans with post-traumatic stress disorder (PTSD), it exacerbates PTSD symptoms, and it contributes to impaired functioning and quality of life. To improve treatment outcomes, it is important to identify risk factors for insomnia and sedative-hypnotic use. Classification and regression trees and logistic regression models were used to identify variables associated with insomnia or sedative-hypnotic use. Key findings include low insomnia diagnosis rates (3.5–5.6%) and high rates of sedative-hypnotics (44.2–49.0%). Younger Veterans and those without a breathing-related sleep disorder (BRSD) were more likely to receive an insomnia diagnosis. Veterans with greater service connection and those with an alcohol/substance use disorder were more likely to be prescribed sedative-hypnotics. Interaction terms may have identified potential groups at risk of being under-diagnosed with insomnia (i.e. non-black Veterans with psychiatric co-morbidity, black Veterans without psychiatric co-morbidity) as well as groups at risk for sedative-hypnotic use (i.e. younger Veterans without BRSD). In sum, Veterans with PTSD have high rates of sedative-hypnotic use despite minimal evidence they are effective. This is counter to recommendations indicating behavioral interventions are the first-line treatment. Policy changes are needed to reduce use of sedative-hypnotics and increase access to behavioral insomnia interventions. 相似文献
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55.
The present paper provides a proof that the Bayes prediction ordering policy developed in [3] is an optimal policy, in the sense that it minimizes the total expected discounted cost of ordering for any finite planning horizon. 相似文献
56.
Let X1 < X2 <… < Xn denote an ordered sample of size n from a Weibull population with cdf F(x) = 1 - exp (?xp), x > 0. Formulae for computing Cov (Xi, Xj) are well known, but they are difficult to use in practice. A simple approximation to Cov(Xi, Xj) is presented here, and its accuracy is discussed. 相似文献
57.
Computerized Scheduling of Seagoing Tankers The tanker scheduling problem considered in this paper is that of the Defense Fuel Supply Center (DFSC) and the Military Sealift Command (MSC) in the worldwide distribution of bulk petroleum products. Routes and cargoes which meet delivery schedule dates for a multiplicity of product requirements at minimum cost are to be determined for a fleet of tankers. A general mathematical programming model is presented, and then a mixed integer model is developed which attempts to reflect the true scheduling task of DFSC and MSC as closely as possible. The problem is kept to within a workable size by the systematic construction of a set of tanker routes which does not contain many possible routes that can be judged unacceptable from practical considerations alone. 相似文献
58.
A modified generalized programming procedure is presented for solving concave programming problems with equality constraints. The procedure constructs convenient linear approximations of the gradient of the dual and finds points where the approximating functions vanish. In the quadratic programming case, the procedure is finitely convergent. Global convergence is established for the non-quadratic case. Illustrative numerical examples are included. 相似文献
59.
Paul S. Dwyer 《海军后勤学研究》1975,22(4):751-775
The general solution process of the Hitchcock transportation problem resulting from the application of the method of reduced matrices may give solutions with some negative xij values. This paper is devoted to a review of the reduced matrices method, an examination of suitable interpretation of sets of xij which include some negative values, and ways of interpreting these values in useful modifications of the Hitchcock problem. Such modifications include a) the reshipment problem, b) the overshipment problem, and c) the transshipment problem. Techniques are developed for determining and eliminating cij which are not optimal. These techniques and results are useful in solving the problems indicated above. The natural applicability of the simple and general method of reduced matrices is emphasized. 相似文献
60.
M. S. Bazaraa 《海军后勤学研究》1973,20(2):357-366
In this study we interpret the exterior penalty function method as a generalized lagrangian metliod which fills duality gaps in nonconvex problems. Geometry and resolution of these gaps from a duality point of view are highlighted. 相似文献