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文章考查了目前网络威慑理论在实践中出现的困境,并研究了云计算对网络威慑的价值对象,攻防能力以及威慑模式选择的影响,认为国家的网络威慑战略将更加倾向于抵消性威慑。基于此,对我国在云计算背景下加强网络安全提出了建议。  相似文献   
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在传统的含储能单元分布式供电系统中,一般都需要多个单向直流变换器和双向直流变换器才能实现其功能。提出一种新的双输入多通道直流变换器,它的功能等效于一个单向直流变换器和一个双向直流变换器。分析了双输入多通道直流变换器的工作原理,给出了变换器的稳态关系式以及能量管理方法,并运用Saber软件进行仿真,验证了理论分析的正确性。该直流变换器除具有双输入Buck直流变换器的优点外,还能实现可再生能源向储电输入源充电。  相似文献   
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Book reviews     
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   
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We consider a periodic review model over a finite horizon for a perishable product with fixed lifetime equal to two review periods. The excess demand in a period is backlogged. The optimal replenishment and demand management (using price) decisions for such a product depend on the relative order of consumption of fresh and old units. We obtain insights on the structure of these decisions when the order of consumption is first‐in, first‐out and last‐in, first‐out. For the FIFO system, we also obtain bounds on both the optimal replenishment quantity as well as expected demand. We compare the FIFO system to two widely analyzed inventory systems that correspond to nonperishable and one‐period lifetime products to understand if demand management would modify our understanding of the relationship among the three systems. In a counterintuitive result, we find that it is more likely that bigger orders are placed in the FIFO system than for a nonperishable product when demand is managed. © 2013 Wiley Periodicals, Inc. Naval Research Logistics, 2013  相似文献   
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本文从干燥机理出发分析了微波干衣优于红外的性能,并且从实验表明微波干衣比用PTC陶瓷板红外干衣平均节能10~30%,平均节时20~40%。  相似文献   
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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   
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