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431.
A. S. Andreou ? K. E. Parsopoulos ? M. N. Vrahatis § G. A. Zombanakis 《Defence and Peace Economics》2013,24(5):481-495
The issue that this paper tackles is the assessment of the relative security benefits that Cyprus and Greece derive in the context of their cooperation on defence matters. This form of cooperation, known as the ‘Integrated Defence Space Doctrine’, aims at defending their interests in the Aegean Sea and the broader East Mediterranean theatre. The paper relies heavily on earlier research on this topic, which deals with the Greek–Cypriot alliance facing an arms race against Turkey, and uses a coefficient especially designed to assess the optimal levels of security and the associated defence expenditure of the two allies. A comparison of the relative security coefficient values for the two allies suggests that the security benefit that Greece derives thanks to its alliance with Cyprus exceeds the corresponding Cypriot benefit by far. Given the importance assigned to human resources by this index, in conjunction with the demographic problems of Greece, this conclusion justifies the recent Greek defence policy revision, emphasizing quality, capital equipment and flexibility of forces. This revision aims at satisfying the security requirements of the alliance and the increasing demands of an arms race against Turkey. 相似文献
432.
Chowdhury (1991) applied Granger causality methods to military expenditure and economic growth series in 55 developing countries. This note applies a similar approach to Australia and finds no causal relationship between military expenditure and growth in either direction. 相似文献
433.
We investigate the link between economic performance and terrorism for 18 Latin American countries from 1970 to 2007, taking into account the potentially complex nature of this link. Panel causality analysis findings indicate that during this period, terrorism had no causal effect on economic growth. By contrast, we find that growth reduced terrorism in the less developed but not in the higher developed Latin American economies. We argue that group-specific differences (linked to patterns of economic development) govern this causal heterogeneity. From a series of negative binomial regressions we gain additional support for our findings, while also identifying further determinants of terrorism. 相似文献
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In signalling its wish to participate in the Additional Protocol at an early stage, Sweden took several steps at the national level long before it actually ratified the protocol in May 2004. In 1998, the Swedish Nuclear Power Inspectorate (SKI) initiated a project to conduct a historical survey of Swedish nuclear weapons research for the period 1945–72. Sweden thus took an important step for the sake of transparency. SKI worked out a general model of how a nationally based survey could be designed, and gradually other states approached SKI in order to learn more about the methods and goals of the historical surveys. In 2002, a cooperative project was initiated between Sweden and Estonia, Latvia, and Lithuania. Finland joined the cooperative effort, and it thus became a dialogue and project carried out by five neighboring states to make national surveys. This article presents summaries of the national reports from Sweden and the Baltic states. 相似文献
438.
Diagnostic clinics are among healthcare facilities that suffer from long waiting times which can worsen medical outcomes and increase patient no-shows. Reducing waiting times without significant capital investments is a challenging task. We tackle this challenge by proposing a new appointment scheduling policy that does not require significant investments for diagnostic clinics. The clinic in our study serves outpatients, inpatients, and emergency patients. Emergency patients must be seen on arrival, and inpatients must be given next day appointments. Outpatients, however, can be given later appointments. The proposed policy takes advantage of this by allowing the postponement of the acceptance of appointment requests from outpatients. The appointment scheduling process is modeled as a two-stage stochastic programming problem where a portion of the clinic capacity is allocated to inpatients and emergency patients in the first stage. In the second stage, outpatients are scheduled based on their priority classes. After a detailed analysis of the solutions obtained from the two-stage stochastic model, we develop a simple, non-anticipative policy for patient scheduling. We evaluate the performance of this proposed, easy-to-implement policy in a simulation study which shows significant improvements in outpatient indirect waiting times. 相似文献
439.
This article introduces the twin robots scheduling problem (TRSP), in which two robots positioned at the opposite ends of a rail are required to deliver items to positions along the rail, and the objective is to minimize the makespan. A proof of ‐hardness of the TRSP is presented, along with exact and heuristic algorithms. Computational results on challenging instances are provided.Copyright © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 119–130, 2014 相似文献
440.
We study new models of scheduled maintenance management for modular systems, consisting of multiple components with respective cycle limits. The cycle limit of each component specifies the time interval in which this component must be repaired or replaced. The goal is to compute a feasible maintenance schedule that minimizes the cost associated with component maintenance. Applications of these models arise in Air Force aircraft maintenance as well as in other arenas with required preventive maintenance. The typical cost structures that arise in practical settings are submodular, which make the resulting models computationally challenging. We develop two efficient and operationally tenable approximation algorithms. We prove constant factor worst‐case guarantees for both algorithms, and present computational experiments showing that these algorithms perform within a few percent of optimality on operationally relevant instances. © 2014 Wiley Periodicals, Inc. Naval Research Logistics 61: 472–488, 2014 相似文献