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271.
The main objective of the paper is to decipher the military expenditure–economic growth relationship, taking the level of economic development (income) into consideration. Our findings suggest the following: (i) military expenditure has a significantly negative relationship to economic growth for the 23 countries with initial incomes (threshold variable) less than or equal to $475.93; (ii) when the threat level is heightened, economic growth (23 countries) is expected to decrease. However, military expenditure in the presence of sufficiently large threats increases growth; (iii) for the remaining 69 countries whose initial incomes (real GDP per capita in 1992 price) exceed $475.93, no significant relationship exists whether the threat variable is taken into consideration or not. 相似文献
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Yang‐Ming Chang 《Defence and Peace Economics》2013,24(2):183-200
This paper presents a simple model to characterize the outcome of a land dispute between two rival parties using a Stackelberg game. Unlike Gershenson and Grossman (2000), we assume that the opposing parties have access to different technologies for challenging and defending in conflict. We derive the conditions under which territorial conflict between the two parties is less likely to persist indefinitely. Allowing for an exogenous destruction term as in Garfinkel and Skaperdas (2000), we show that, when the nature of conflict becomes more destructive, the likelihood of a peaceful outcome, in which the territory’s initial possessor deters the challenging party, increases if the initial possessor holds more intrinsic value for the disputed land. Following Siqueira (2003), our model has policy implications for peace through third‐party intervention. 相似文献
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针对常规海上航线决策没有考虑决策选择过程的问题,引入多选择决策场理论( MDFT),构建了海上能源通道航线动态决策模型。基于信息完备、信息不确定和特殊情况等三种情景想定,进行了海上能源通道航线规划决策及其实验仿真。结果表明,决策过程受时间压力和信息质量的制约,时间压力会制约决策质量,同时还可能引起“偏好逆转”现象,信息不确定也会导致确定性决策。该模型不仅综合考虑了海上能源通道航线选择时需关注的各类要素,且模型参数可动态调整,进而能合理模拟真实的海上状况和决策过程。 相似文献
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一种结合弹道规律的模糊交互式多模型算法 总被引:1,自引:0,他引:1
针对交互式多模型算法中转移概率矩阵与实际运动不匹配而影响跟踪精度的问题,通过分析某型导弹的典型弹道,将弹道规律融合到模型概率转移矩阵中,然后将转移概率模糊化处理,提出了一种基于弹道规律的模糊交互式多模型算法,然后以导弹蛇形运动转至比例导引的机动过程为例进行了仿真验证,比较了典型交互式多模型算法和模糊交互式多模型算法的跟踪性能。仿真结果表明:该算法可显著提高导弹机动段的跟踪精度。 相似文献
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Modeling and solution for the ship stowage planning problem of coils in the steel industry 下载免费PDF全文
We consider a ship stowage planning problem where steel coils with known destination ports are to be loaded onto a ship. The coils are to be stowed on the ship in rows. Due to their heavy weight and cylindrical shape, coils can be stowed in at most two levels. Different from stowage problems in previous studies, in this problem there are no fixed positions on the ship for the coils due to their different sizes. At a destination port, if a coil to be unloaded is not at a top position, those blocking it need to be shuffled. In addition, the stability of ship has to be maintained after unloading at each destination port. The objective for the stowage planning problem is to minimize a combination of ship instability throughout the entire voyage, the shuffles needed for unloading at the destination ports, and the dispersion of coils to be unloaded at the same destination port. We formulate the problem as a novel mixed integer linear programming model. Several valid inequalities are derived to help reducing solution time. A tabu search (TS) algorithm is developed for the problem with the initial solution generated using a construction heuristic. To evaluate the proposed TS algorithm, numerical experiments are carried out on problem instances of three different scales by comparing it with a model‐based decomposition heuristic, the classic TS algorithm, the particle swarm optimization algorithm, and the manual method used in practice. The results show that for small problems, the proposed algorithm can generate optimal solutions. For medium and large practical problems, the proposed algorithm outperforms other methods. © 2015 Wiley Periodicals, Inc. Naval Research Logistics 62: 564–581, 2015 相似文献