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The US-led ‘war on terror’ dramatically changed America's security strategy towards Africa. But more fundamentally, it threw the Horn of Africa on the centre stage of global counter-terrorism. A double-edged blade, counter-terrorism has at once catalysed peace processes and intensified insecurity, with Islamic radicalism at the core of the regional storm. Governments utilised the threat of terrorism for political ends, defending old security paradigms that prioritised regime stability over human security. Africa integrated counter-terrorism into its emerging security agenda, but insufficient funds, operational constraints and poor coordination with international initiatives have hampered meaningful progress. Washington, laudably, launched a robust counter-terrorist campaign, but its high-handed military-heavy style put fragile democracies at risk while lapses in its overall policy risk triggering proxy wars. This essay examines the impact of counter-terrorism on security in the Horn of Africa. It argues for stronger coordination between national, regional and international initiatives to curb international terrorism.  相似文献   
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Claims that China is the only nuclear power currently expanding its arsenal fail to take into account the technical, historical, and bureaucratic realities that shaped China's nuclear posture and drive its ongoing modernization. China's strategic modernization is largely a process of deploying new delivery systems, not designing new nuclear warheads; the majority of its new missiles are conventionally armed. Today, China maintains the smallest operationally deployed nuclear force of any of the legally recognized nuclear weapon states, operates under a no-first-use pledge, and keeps its warheads off alert. The modernization of China's delivery systems is the culmination of a decades-long plan to acquire the same capabilities deployed by the other nuclear powers. U.S. concerns about this modernization focus too much on deterring a deliberate Chinese attack and ignore the risk that modernized U.S. and Chinese forces could interact in unexpected ways during a crisis, creating uncontrollable escalatory pressures. To manage this risk, Washington should assure Chinese leaders that it does not seek to deny China's deterrent, in exchange for some understanding that China will not seek numerical parity with U.S. nuclear forces.  相似文献   
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Britain underestimated the importance of the naval mine in the years leading up to the First World War and entered the conflict unprepared for an extended mine campaign. Traditional interpretations of the mine's position are limited and neglect the broader political and economic factors influencing its development. The mine was a peripheral technology representative of the rapid technological change in the period, and its development was affected by financial constraints, international diplomacy and naval administration. Because of structural impediments, however, and despite significant resources devoted to the weapon, the mine faced obstacles which led to both limited stocks and inadequate plans for use at the opening of the First World War.  相似文献   
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We present a large‐scale network design model for the outbound supply chain of an automotive company that considers transportation mode selection (road vs. rail) and explicitly models the relationship between lead times and the volume of flow through the nodes of the network. We formulate the problem as a nonlinear zero‐one integer program, reformulate it to obtain a linear integer model, and develop a Lagrangian heuristic for its solution that gives near‐optimal results in reasonable time. We also present scenario analyses that examine the behavior of the supply chain under different parameter settings and the performance of the solution procedures under different experimental conditions. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2007  相似文献   
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In recent years, some attention has been devoted to the application of techniques of control theory to inventory management. In particular, H. Vassian (1955) developed a model for a periodic review inventory system utilizing techniques of discrete variable servomechanisms to analyze the system in a cost-free structure. The resulting model is inherently deterministic, however, and emphasizes the control of inventory fluctuation about a safety level by selecting an appropriate order policy. Such an order policy is defined only up to an arbitrary method of forecasting customer demands. The present paper is a continuation of the model developed by Vassian in which exponential smoothing is used as a specific forecasting technique. Full recognition of the probabilistic nature of demand is taken into account and the requirement of minimizing expected inventory level is imposed. In addition, explicit formulas for the variance in inventory are derived as functions of the smoothing constant and the tradeoff between small variance and rapid system response is noted. Finally, in an attempt to remove the bias inherent in exponential smoothing, a modification of that technique is defined and discussed as an alternate forecasting method.  相似文献   
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