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201.
202.
Amanda R. Moodie 《The Nonproliferation Review》2013,20(3-4):383-386
203.
Pinar Derin‐Güre 《Defence and Peace Economics》2013,24(4):393-395
This paper investigates the economic roots of separatist terrorism in Turkey. The political conventional wisdom is that poverty in highly Kurdish‐populated, south‐eastern Turkey is one of the most important causes of separatist terrorism and Turkish–Kurdish conflict in Turkey. Therefore, many economic policies have been implemented to improve the economic conditions in the south‐eastern part of the country. Using the Global Terrorism Database and Vector Autoregression (VAR) methodology, I find that there is no causal relationship between economic conditions in south‐eastern Turkey and separatist terrorism. Therefore policy‐makers should be cautious in using economic measures to prevent separatist terrorism in Turkey. 相似文献
204.
205.
In their article in this journal, James, Solberg and Wolfson (1999) challenge our findings that two states are more likely to have peaceful relations if they are both democratic. They claim to develop a simultaneous system of two equations showing that peace and democracy foster each other, and that the effect of peace in encouraging democracy is stronger than that of democracy on peace. Their analysis, however, is flawed. Their research design employs measures of dispute and joint democracy that are inferior to those now common in the literature, and their equation for predicting peace is not properly specified. These problems distort their results. Even so, their results provide evidence of the pacific benefits of democracy. Analyses we conduct with a more completely specified model reveal stronger support for the democratic “ peace. Furthermore, a test of the effect of interstate conflict on democracy should be done at the national (or monadic) level of analysis; but James et al. perform a dyadic analysis. In a monadic test using vector autoregression, we find that disputes make no contribution to explaining the character of regimes. Even with their dyadic method, their finding that peace promotes democracy is not robust Including a crucial control variable, the ratio of militarily relevant national capabilities, that James et al. omitted, dramatically alters their findings. 相似文献
206.
207.
This paper considers a discrete time, single item production/inventory system with random period demands. Inventory levels are reviewed periodically and managed using a base‐stock policy. Replenishment orders are placed with the production system which is capacitated in the sense that there is a single server that sequentially processes the items one at a time with stochastic unit processing times. In this setting the variability in demand determines the arrival pattern of production orders at the queue, influencing supply lead times. In addition, the inventory behavior is impacted by the correlation between demand and lead times: a large demand size corresponds to a long lead time, depleting the inventory longer. The contribution of this paper is threefold. First, we present an exact procedure based on matrix‐analytic techniques for computing the replenishment lead time distribution given an arbitrary discrete demand distribution. Second, we numerically characterize the distribution of inventory levels, and various other performance measures such as fill rate, base‐stock levels and optimal safety stocks, taking the correlation between demand and lead times into account. Third, we develop an algorithm to fit the first two moments of the demand and service time distribution to a discrete phase‐type distribution with a minimal number of phases. This provides a practical tool to analyze the effect of demand variability, as measured by its coefficient of variation, on system performance. We also show that our model is more appropriate than some existing models of capacitated systems in discrete time. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
208.
We consider an M/G/1 retrial queue with finite capacity of the retrial group. First, we obtain equations governing the dynamic of the waiting time. Then, we focus on the numerical inversion of the density function and the computation of moments. These results are used to approximate the waiting time of the M/G/1 queue with infinite retrial group for which direct analysis seems intractable. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
209.
Antoon W.J. Kolen Jan Karel Lenstra Christos H. Papadimitriou Frits C.R. Spieksma 《海军后勤学研究》2007,54(5):530-543
In interval scheduling, not only the processing times of the jobs but also their starting times are given. This article surveys the area of interval scheduling and presents proofs of results that have been known within the community for some time. We first review the complexity and approximability of different variants of interval scheduling problems. Next, we motivate the relevance of interval scheduling problems by providing an overview of applications that have appeared in literature. Finally, we focus on algorithmic results for two important variants of interval scheduling problems. In one variant we deal with nonidentical machines: instead of each machine being continuously available, there is a given interval for each machine in which it is available. In another variant, the machines are continuously available but they are ordered, and each job has a given “maximal” machine on which it can be processed. We investigate the complexity of these problems and describe algorithms for their solution. © 2007 Wiley Periodicals, Inc. Naval Research Logistics, 2007 相似文献
210.
This study analyzes the determinants of arms production in 15 countries using annual panel data from 1997 to 2002. The results suggest that real GDP per capita, military expenditures, arms exports, and arms imports are positively related to arms production. 相似文献