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111.
    
Abstract

Political parties with an armed history are not unusual, yet how these groups function in politics after the transition has largely been ignored. This special issue examines armed groups in party politics, using single and comparative case studies. The introduction forwards five recommendations for future research: (1) We need to see more comparisons across taken for granted boundaries; (2) the consequences for democracy should figure more prominently in our analysis of armed groups; (3) think more critically about standards and conceptual tools; (4) critically examine the interaction between levels of analysis; and (5) methodological pluralism would enrich the field.  相似文献   
112.
    
There is often a call in any organization to make the system ‘more efficient’. This document describes a novel framework for measuring organizational efficiency at the microeconomic level. We show how this framework can be used to monitor an organization using data typically available in extant performance management frameworks. This is most useful in large organizations with eclectic outputs where resources may be too constrained to perform industry-level analyses, such as data envelope analysis, to infer efficiency. This method helps illuminate how the factors of an organization’s internal practices can affect its efficient use of resources.  相似文献   
113.
    
This paper discusses a novel application of mathematical programming techniques to a regression problem. While least squares regression techniques have been used for a long time, it is known that their robustness properties are not desirable. Specifically, the estimators are known to be too sensitive to data contamination. In this paper we examine regressions based on Least‐sum of Absolute Deviations (LAD) and show that the robustness of the estimator can be improved significantly through a judicious choice of weights. The problem of finding optimum weights is formulated as a nonlinear mixed integer program, which is too difficult to solve exactly in general. We demonstrate that our problem is equivalent to a mathematical program with a single functional constraint resembling the knapsack problem and then solve it for a special case. We then generalize this solution to general regression designs. Furthermore, we provide an efficient algorithm to solve the general nonlinear, mixed integer programming problem when the number of predictors is small. We show the efficacy of the weighted LAD estimator using numerical examples. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
114.
    
The purpose of this article is to present an algorithm for globally maximizing the ratio of two convex functions f and g over a convex set X. To our knowledge, this is the first algorithm to be proposed for globally solving this problem. The algorithm uses a branch and bound search to guarantee that a global optimal solution is found. While it does not require the functions f and g to be differentiable, it does require that subgradients of g can be calculated efficiently. The main computational effort of the algorithm involves solving a sequence of subproblems that can be solved by convex programming methods. When X is polyhedral, these subproblems can be solved by linear programming procedures. Because of these properties, the algorithm offers a potentially attractive means for globally maximizing ratios of convex functions over convex sets. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
115.
    
A system reliability is often evaluated by individual tests of components that constitute the system. These component test plans have advantages over complete system based tests in terms of time and cost. In this paper, we consider the series system with n components, where the lifetime of the i‐th component follows exponential distribution with parameter λi. Assuming test costs for the components are different, we develop an efficient algorithm to design a two‐stage component test plan that satisfies the usual probability requirements on the system reliability and in addition minimizes the maximum expected cost. For the case of prior information in the form of upper bounds on λi's, we use the genetic algorithm to solve the associated optimization problems which are otherwise difficult to solve using mathematical programming techniques. The two‐stage component test plans are cost effective compared to single‐stage plans developed by Rajgopal and Mazumdar. We demonstrate through several numerical examples that our approach has the potential to reduce the overall testing costs significantly. © 2002 John Wiley & Sons, Inc. Naval Research Logistics, 49: 95–116, 2002; DOI 10.1002/nav.1051  相似文献   
116.
    
This article argues that deterrence theory can be applied to counterterrorism. Doing so requires broadening the traditional concept of deterrence by punishment, expanding deterrence by denial to include defense, mitigation, and strategic hindrance, and developing deterrence by delegitimization to influence the political, ideological, and religious rationales informing terrorist behavior. In practice, deterring terrorism requires tailoring threats against state and individual facilitators, diffusing the intended consequences of terrorism, and manipulating terrorist self–restraints. When these and other deterrent leverages are applied simultaneously against various actors and processes involved in terrorism, coercion can be achieved.  相似文献   
117.
    
The German invasion in Norway in April 1940 was unique in that it was the first major ‘triphibious’ campaign. It was an operation that was equally dependent upon naval, air and ground forces for success. Norway had long been of interest to German strategists, especially naval thinkers. However, no serious Wehrmacht plans for occupying Norway were even started until December 1939. A small group of staff officers of the three services put together a comprehensive plan in a matter of weeks. The article examines the effectiveness of the German interservice co‐operation and OKW leadership in a very tough and close run campaign. Although there were numerous problems, interservice co‐operation was fairly effective at the tactical and operational levels. Indeed, the Germans won the campaign largely because their services worked together much better than their Allied opponents.  相似文献   
118.
    
This article is a portrait of Admiral Sergei Gorshkov, commander of the Soviet Navy for almost three decades, from 1956–85. The author, a retired US Navy admiral with a Harvard PhD in Russian studies who served as both defense and naval attaché in Moscow, draws on numerous face-to-face interactions with Gorshkov. He also explores Gorshkov's memoirs that were published recently in Russia but have not appeared in an English translation. The paper is not only a first-hand account of an important historical figure, but also a window into the world of military-to-military diplomacy and intelligence during the Cold War.  相似文献   
119.
    
Ordered flow shop models have appeared in the literature since the mid‐1970s and proportionate flow shop models have appeared since the early 1980s. We provide a detailed review of these models along with some analysis and potential topics for future research. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
120.
    
1 1This research was funded in part by a grant from the Lowe Institute of Political Economy. The corresponding author is S. Brock Blomerg. We thank Chris Blomberg and Brianna Loyosa for their excellent research assistance on the project. This paper presents an empirical analysis of what drives congressional legislation on terrorism during the period 1995 to 2010. We utilize and augment current methodology to compile and analyze data on sponsorship and cosponsorship of terrorism related data. Our results on the sources of legislation on terrorism are largely in line with past examinations of the importance of committee membership and leadership, party majority-ship, and other political factors. Further, we find that the most significant and robust drive for legislation on terrorism is the September 11th attacks. And while the impact of 9/11 affected legislative productivity everywhere, we find that it most significantly affected states surrounding New York and Washington D.C. Our results indicate that the economy may be one factor motivating politicians to legislate on terrorism; however, these results are not robust.  相似文献   
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