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131.
South Korea is threatened by its troubled relationship with North Korea. North Korea possesses a large cache of missiles as well as chemical and biological weapons, and the future potential to mount nuclear weapons on its missiles. The United States is also challenged because of its defense commitments to Seoul. As a countermeasure, the United States and South Korea decided to deploy Terminal High Altitude Area Defense (THAAD) missile defenses in South Korea. However, China has objected. Chinese scholars believe the THAAD radar would be able to track Chinese inter-continental ballistic missiles, thereby weakening their deterrent. A technical analysis does not support this assertion. However, it is vital for South Korea, given its proximity and economic interdependence, to reassure China. South Korea should highlight that THAAD will be deployed by the United States Forces Korea and is not a commitment by Seoul to become part of U.S.-led missile defenses in the Asia-Pacific. 相似文献
132.
Stochastic dynamic programming models are attractive for multireservoir control problems because they allow non‐linear features to be incorporated and changes in hydrological conditions to be modeled as Markov processes. However, with the exception of the simplest cases, these models are computationally intractable because of the high dimension of the state and action spaces involved. This paper proposes a new method of determining an operating policy for a multireservoir control problem that uses stochastic dynamic programming, but is practical for systems with many reservoirs. Decomposition is first used to reduce the problem to a number of independent subproblems. Each subproblem is formulated as a low‐dimensional stochastic dynamic program and solved to determine the operating policy for one of the reservoirs in the system. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006 相似文献
133.
In this article we introduce a 2‐machine flowshop with processing flexibility. Two processing modes are available for each task: namely, processing by the designated processor, and processing simultaneously by both processors. The objective studied is makespan minimization. This production environment is encountered in repetitive manufacturing shops equipped with processors that have the flexibility to execute orders either individually or in coordination. In the latter case, the product designer exploits processing synergies between two processors so as to execute a particular task much faster than a dedicated processor. This type of flowshop environment is also encountered in labor‐intensive assembly lines where products moving downstream can be processed either in the designated assembly stations or by pulling together the work teams of adjacent stations. This scheduling problem requires determining the mode of operation of each task, and the subsequent scheduling that preserves the flowshop constraints. We show that the problem is ordinary NP‐complete and obtain an optimal solution using a dynamic programming algorithm with considerable computational requirements for medium and large problems. Then, we present a number of dynamic programming relaxations and analyze their worst‐case error performance. Finally, we present a polynomial time heuristic with worst‐case error performance comparable to that of the dynamic programming relaxations. © 2003 Wiley Periodicals, Inc. Naval Research Logistics, 2004. 相似文献
134.
Tobias Brueggemann Johann L. Hurink Tjark Vredeveld Gerhard J. Woeginger 《海军后勤学研究》2011,58(8):795-803
We investigate the quality of local search heuristics for the scheduling problem of minimizing the makespan on identical parallel machines. We study exponential size neighborhoods (whose size grows exponentially with the input length) that can be searched in polynomial time, and we derive worst‐case approximation guarantees for the local optima of such neighborhoods. The so‐called split neighborhood splits a feasible schedule into two layers, and then recombines the two layers by finding a perfect matching. We show that the makespan of every local optimum for split is at most a factor of 2 away from the globally optimal makespan. We then combine the split neighborhood with two neighborhoods from the literature. The combination of split with the jump neighborhood only marginally improves the approximation guarantee, whereas the combination with the lexicographic‐jump neighborhood decreases the approximation guarantee from 2 to 3/2. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
135.
Brendan Simms Bruce Hoffman Daniel W. Fitz‐Simons Robert H. Dorff Jennifer Morrison Taw Gabriel Marcella 《Small Wars & Insurgencies》2013,24(1):127-139
Frank Zimmer, Bismarcks Kampf gegen Kaiser Franz Joseph Konigsgratz und seine Folgen. Graz, Vienna, Cologne: Styria Verlag 1996. Pp.203,49 illus., 1 map. OS 350/DM 49. ISBN 3–222–12377–2. Saul Zadka, Blood in Zion: How the Jewish Guerrillas drove the British out of Palestine. London and Washington: Brassey's, 1995. Pp.227, chron., illus., index. £19.95. ISBN 1–85753–136–1. Theodore L. Gatchel, At the Water's Edge: Defending against the Modern Amphibious Assault. Annapolis, MD: Naval Institute Press, 1996. Pp.xvi+217, notes, biblio, index. $36.95. ISBN 1–55750–308–7. Max G. Manwaring and William J. Olson (eds.) Managing Contemporary Conflict: Pillars of Success. Boulder, CO: Westview Press, 1996. Pp.269, no index. $65 (cloth); $25 (paper). ISBN 0–8133–8969 and 9978–5 Chris Seiple, The US Military/NGO Relationship in Humanitarian Interventions, Carlisle Barracks, PA: The Richard L. Millett and Michael Gold‐Biss (eds.) Beyond Praetorianism: The Latin American Military in Transition. University of Miami: North/South Center Press; Boulder, CO: Lynne Rienner, 1996. Pp.xv +317, index. $24.95. ISBN 1–5745–000–9. Rudolph C. Barnes Jr, Military Legitimacy: Might and Right in the New Millennium. London and Portland, OR: Frank Cass, 1996. Pp.199, select biblio., index. £27.50/$39.50, ISBN 0–714–4624–5. 相似文献
136.
Ordered flow shop models have appeared in the literature since the mid‐1970s and proportionate flow shop models have appeared since the early 1980s. We provide a detailed review of these models along with some analysis and potential topics for future research. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2013 相似文献
137.
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
138.
Robert Ayanian 《Defence and Peace Economics》2013,24(1):51-65
In this paper I shift the focus of real exchange rate analysis from conventional macroeconomic variables, which have failed to explain changes in floating real dollar exchange rates, to military security variables, which show an uncanny ability to explain the pattern of floating real exchange rate changes among NATO‐area floating currencies from early 1973 through the failed Soviet coup of August, 1991. 相似文献
139.
ABSTRACTThis study seeks to evaluate the threat of malicious chemical use by non-state actors. It finds that non-state actors have primarily turned to ready-to-use crude chemical weapons (CW) instead of traditional CW agents. Interestingly, the worst crude CW attacks have been more destructive than those employing traditional CW. Scenarios for catastrophic consequences exist, but chemical attacks have typically been used to accomplish tactical goals, which leverage psychological and economic impacts. Therefore, successful efforts to counter CW proliferation by non-state actors must be substantially different from those targeting states. 相似文献
140.
设计了四轮全向移动机器人的传感器信息采集硬件电路,并通过分析四轮全向移动机器人的运动学模型,提出了基于TI公司最新研发的TMS320F28069为主控制器的直流电机双闭环速度控制方案.试验结果表明:所提控制方案能够满足四轮全向移动机器人速度控制的要求,且响应速度快、误差小. 相似文献