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561.
2016年年初以来,朝鲜先后进行了第四次、第五次核试验,在此背景下,韩国国防部宣布,韩美同意在韩国部署末段高空区域防御系统——"萨德"导弹防御系统,朝鲜半岛地区风云再起。美韩此举使原本不安的东北亚局势更加紧张,诱发并恶化着东北亚地区大国家间潜存的"安全困境"。韩国决定部署"萨德"不仅严重僵化了中韩的国际关系,使得原本对峙局面下的朝韩两国局势更加紧张,更破坏了东北亚军事战略均衡,地区"新冷战"格局逐步形成。 相似文献
562.
Shishir Upadhyaya 《Defence Studies》2017,17(1):63-83
This paper examines the ongoing expansion of China’s maritime power in the Indian Ocean region and analyses its potential impact on the extant balance of Sino-Indian maritime power in the region. It posits that the expanding Chinese maritime power in the Indian Ocean could seriously challenge India’s geostrategic advantage in the near future and that India can no longer take for granted its strategic location at the centre of the Indian Ocean nor the strength of its historical ties with the various regional states. It further argues that the current Indian maritime strategy for the Indian Ocean region, to be the “net security provider” for the entire region, is unsustainable and thus needs to be reviewed and rebuilt leveraging the geographic advantage enjoyed by India over China in the Indian Ocean. 相似文献
563.
Yan Cimon 《Defense & Security Analysis》2017,33(4):333-346
With the Canada First Defence Strategy, Canada has put forth a major opportunity to reconcile national security imperatives and industrial policy. The Jenkins Report (2013) set out to examine ways to use that procurement effort to foster key industrial capabilities (KICs) that would put the Canadian defence industry at an advantage both nationally and internationally. The Canadian defence industry should then develop highly focused capabilities with a view to moving up global value chains. As such, KICs that hold the best potential should be selected. They should be sustained through a range of strategies that are however contingent on the elimination of policy gaps. This leads to a balancing act between the need to control intellectual property assets versus accessing them in a world where national boundaries are eroded. Canada’s industry should target opportunities outside North America while continuing to focus on better integration with the North American industry. 相似文献
564.
Leila Mohammadi 《海军后勤学研究》2017,64(7):566-579
We investigate the joint signature of coherent systems, under the assumption that the components have independent and identically distributed lifetimes. The joint signature, for a particular ordering of failure times, is an ‐dimensional matrix depending solely on the composition of the systems and independent of the underlying distribution function of the component lifetimes. The elements of the ‐dimensional matrix are formulated based on the joint signatures of numerous series of parallel systems. The number of the joint signatures involved is an exponential function of the number of the minimal cut sets of each original system and may, therefore, be significantly large. We prove that although this number is typically large, a great number of the joint signatures are repeated, or removed by negative signs. We determine the maximum number of different joint signatures based on the number of systems and components. It is independent of the number of the minimal cut sets of each system and is polynomial in the number of components. Moreover, we consider all permutations of failure times and demonstrate that the results for one permutation can be of use for the others. Our theorems are applied to various examples. The main conclusion is that the joint signature can be computed much faster than expected. 相似文献
565.
We analyze an interdiction scenario where an interceptor attempts to catch an intruder as the intruder moves through the area of interest. A motivating example is the detection and interdiction of drug smuggling vessels in the Eastern Pacific and Caribbean. We study two models in this article. The first considers a nonstrategic target that moves through the area without taking evasive action to avoid the interdictor. We determine the optimal location the interceptor should position itself to best respond when a target arrives. The second model analyzes the strategic interaction between the interceptor and intruder using a Blotto approach. The intruder chooses a route to travel on and the interceptor chooses a route to patrol. We model the interaction as a two‐player game with a bilinear payoff function. We compute the optimal strategy for both players and examine several extensions. © 2017 Wiley Periodicals, Inc. Naval Research Logistics, 64: 29–40, 2017 相似文献
566.
David R. Morrison Jason J. Sauppe Wenda Zhang Sheldon H. Jacobson Edward C. Sewell 《海军后勤学研究》2017,64(1):64-82
The cyclic best‐first search (CBFS) strategy is a recent search strategy that has been successfully applied to branch‐and‐bound algorithms in a number of different settings. CBFS is a modification of best‐first search (BFS) that places search tree subproblems into contours which are collections of subproblems grouped in some way, and repeatedly cycles through all non‐empty contours, selecting one subproblem to explore from each. In this article, the theoretical properties of CBFS are analyzed for the first time. CBFS is proved to be a generalization of all other search strategies by using a contour definition that explores the same sequence of subproblems as any other search strategy. Further, a bound is proved between the number of subproblems explored by BFS and the number of children generated by CBFS, given a fixed branching strategy and set of pruning rules. Finally, a discussion of heuristic contour‐labeling functions is provided, and proof‐of‐concept computational results for mixed‐integer programming problems from the MIPLIB 2010 database are shown. © 2017 Wiley Periodicals, Inc. Naval Research Logistics, 64: 64–82, 2017 相似文献
567.
Satellite constellation design for forest fire monitoring via a stochastic programing approach 下载免费PDF全文
There is significant value in the data collected by satellites during and after a natural disaster. The current operating paradigm in practice is for satellites to passively collect data when they happen to fly over a disaster location. Conversely, this article considers the alternative approach of actively maneuvering satellites to fly directly overhead of the disaster site on a routine basis. Toward this end, we seek to compute a satellite constellation design that minimizes the expected maneuver costs for monitoring an unknown forest fire. In this article, we present a 2‐stage stochastic programing model for this problem as well as a accelerated L‐shaped decomposition approach. A comparison between our approach and the current operating paradigm indicates that our solution provides longer duration data collections and a greater number of data collections. Analysis also shows that our proposed solution is robust over a wide array of scenarios. 相似文献
568.
Jacqueline L. Hazelton 《战略研究杂志》2017,40(1-2):68-91
This article analyzes the political utility of US drone strikes theoretically and deductively. Placing strikes within the context of the theorized political functions of force and considering how they fit into two grand strategies, restraint and selective engagement, I argue that these strikes buy the United States relatively little in the way of political effects assuring its own security because the terrorism threat they are intended to combat is a limited one within the skein of US global interests. Furthermore, their contribution to counter-terrorism efforts is likely to diminish with the adoption of armed drones by non-state actors. Drone strikes can, however, provide leverage over recalcitrant US client states while reassuring liberal partners and giving them some leverage over US choices. In addition, within the counter-terrorism sphere, drone strikes are less likely to inflame popular opinion than are alternative uses of force. This analysis contributes to an increasingly rigorous examination of the strikes’ role in US foreign and security policy. 相似文献
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