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221.
J. M. Quinn 《Defence and Peace Economics》2013,24(5):536-554
This study models the structural sources of variation in the use of selective (discriminate) repression within 89 civil wars fought between 1981 and 2005. The severity of repressive violence is modeled as a function of the amount of territory being contested by the insurgents. This idea is operationalized using measures of the location, size, and density of insurgency violence. The analysis finds evidence that the repressive behavior of both governments and rebel groups is linked to conflict geography. Governments violate physical integrity rights more frequently and kill more civilians the greater the overall amount of territory under contestation. Rebels kill more civilians in highly dispersed insurgencies that lack a clear epicenter. 相似文献
222.
A. Sokri 《Defence and Peace Economics》2013,24(6):645-653
A nonlinear optimization model is developed in this paper to identify the optimal replacement strategy for military aircraft. In the model, the aircraft operating and maintenance (O&M) costs per available year are estimated as a function of age during the aircraft life cycle. After determining the optimal replacement policy, the model is applied to the CF Long-Range Patrol CP-140A Arcturus fleet. A sensitivity analysis is also carried out to assess the impact of some key model parameters on the result. 相似文献
223.
AbstractThis paper examines the impact of civil war on military expenditure. We employ two measures of military expenditure: the share of military expenditure in general government expenditure and the logarithm of military expenditures. We would reasonably expect a priori that military expenditure as a share of general government expenditure increases during a civil war and that such increases would taper off over the duration of a civil war. We also explore whether the termination of a civil war induces a decline in the share of military expenditure as a share of the general government expenditure in the short-run. We find evidence the of share of military expenditure increases during a civil war and falls in the year succeeding the end of a civil war, and, in particular, if a war ends in a peace treaty. The level of military expenditures, however, rises during civil wars and does not appear to decline in the short-term after the end of a civil war. 相似文献
224.
NJUNGA M MULIKITA 《African Security Review》2013,22(4):105-115
This article argues that whereas the waves of democratization which enveloped the continent in the early 1990s following the collapse of Eastern European one-party socialism genera ted expectations of a ‘new dawn’ for ‘good governance’ and sustainable human development on the continent, one wave after another appears to have suffered serious setbacks. Indeed, a decade later, some of the most articulate pro-democracy leaders, who came into office on the crest of the democratic waves of the 1990s have sought to manipulate their countries' constitutions in order to perpetuate their presidential tenure. Such undemocratic behaviour will only fuel speculation in the industrialized world that the New Partnership for Africa's Development is just another decorative blue-print drawn up by beleaguered African despots in order to obtain new resource inflows at a time the international community under the hegemonic leadership of the Uni ted States will be wholly preoccupied with rebuilding post-Saddam Iraq and the Israeli-Palestinian roadmap. 相似文献
225.
In the classical multiprocessor scheduling problem independent jobs must be assigned to parallel, identical machines with the objective of minimizing the makespan. This article explores the effect of assignment restrictions on the jobs for multiprocessor scheduling problems. This means that each job can only be processed on a specific subset of the machines. Particular attention is given to the case of processing times restricted to one of two values, 1 and λ, differing by at most 2. A matching based polynomial time ε‐approximation algorithm is developed that has a performance ratio tending to . This algorithm is shown to have the best possible performance, tending to 3/2, for processing times 1 and 2. For the special case of nested processing sets, i.e., when the sets of machines upon which individual jobs may be assigned are non‐overlapping, the behavior of list scheduling algorithms is explored. Finally, for assignment restrictions determined by just one characteristic of the machines, such as disc storage or memory constraint in the case of high performance computing, we contribute an algorithm that provides a 3/2 worst case bound and runs in time linear in the number of jobs. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
226.
This study presents power‐of‐two policies for a serial inventory system with constant demand rate and incremental quantity discounts at the most upstream stage. It is shown that an optimal solution is nested and follows a zero‐inventory ordering policy. To prove the effectiveness of power‐of‐two policies, a lower bound on the optimal cost is obtained. A policy that has a cost within 6% of the lower bound is developed for a fixed base planning period. For a variable base planning period, a 98% effective policy is provided. An extension is included for a system with price dependent holding costs. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
227.
We consider a system that depends on a single vital component. If this component fails, the system life will terminate. If the component is replaced before its failure then the system life may be extended; however, there are only a finite number of spare components. In addition, the lifetimes of these spare components are not necessarily identically distributed. We propose a model for scheduling component replacements so as to maximize the expected system survival. We find the counterintuitive result that when comparing components' general lifetime distributions based on stochastic orderings, not even the strongest ordering provides an a priori guarantee of the optimal sequencing of components. © 2008 Wiley Periodicals, Inc. Naval Research Logistics, 2008 相似文献
228.
In this paper, a branch-and-bound procedure is presented for treating the general knapsack problem. The fundamental notion of the procedure involves a variation of traditional branching strategies as well as the incorporation of penalties in order to improve bounds. Substantial computational experience has been obtained, the results of which would indicate the feasibility of the procedure for problems of large size. 相似文献
229.
This paper analyzes the problem faced by a field commander who, confronted by an enemy on N battlefields, must determine an interdiction policy for the enemy's logistics system which minimizes the amount of war material flowing through this system per unit time. The resource utilized to achieve this interdiction is subject to constraint. It can be shown that this problem is equivalent to determining the set of arcs Z* to remove subject to constraint from a directed graph G such that the resulting maximal flow is minimized. A branch and bound algorithm for the solution to this problem is described, and a numerical example is provided. 相似文献
230.
A. S. Goldman 《海军后勤学研究》1969,16(1):111-120
Although industry is expected to design hardware to fit into a general support system and to be capable of arguing life-cycle system costs, adequate information has not been available on the support system in terms of policies and operating decision rules. Policies and operating decisions by users dominate engineering design decisions in determining life-cycle support costs. The relative effect of each of these decision areas on support costs has yet to be resolved empirically. Without an understanding of the sensitivity of support costs to alternative designs, capability is limited in design improvement and support of end items. Life-cycle costing of analysis under cost-effectiveness and the maintainability of integrated logistics support is open to question. 相似文献