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111.
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   
112.
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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114.
To manage their assets at an enterprise level, defense organizations have turned to portfolio theory for the planning, analysis and management of their military forces and materiel. Despite being well established in the commercial sector, the application of portfolio approaches in defense is problematic. The vexatious question for defense of how to define and measure benefits arising is complicated by the increased utility and effectiveness achieved through networking of military forces and the equipment they use. The authors discuss the challenges for defense in using a portfolio approach and propose a conceptual model for dealing with the effects arising from networking with information and communications technologies.  相似文献   
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116.
In this article we discuss a processor sharing queueing model for a stored program controlled telephone exchange. The model incorporates the effects of both call requests and operator tasks on the load of the processor. Newly arriving call requests and operator tasks can either be admitted or rejected and for this decision the state of the queue at the moment of arrival is available as information. To guarantee a high level of service, we formulate a constrained optimization problem. Two types of access control, viz., partitioning policies and sharing policies, are considered. The optimization problem is solved for partitioning policies and the performance of both types of policies is compared. © 1993 John Wiley & Sons, Inc.  相似文献   
117.
Necessary and sufficient conditions are specified for a general theory of additive measurement that presumes very little set-theoretic structure. The theory is illustrated for numerical representations in extensive, conjoint, difference, threshold, expected utility, probability, ambiguity, and subset measurement. © 1992 John Wiley & Sons, Inc.  相似文献   
118.
An efficient algorithm for determining the optimal arrival schedule for customers in a stochastic service system is developed. All customers arrive exactly when scheduled, and service times are modeled as iid Erlang random variables. Costs are incurred at a fixed rate per unit of time each customer waits for service, and an additional cost is incurred for every unit of time the server operates beyond a scheduled closing time. The objective is to minimize total operating cost. This type of problem arises in many operational contexts including transportation, manufacturing, and appointment‐based services. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 549–559, 1999  相似文献   
119.
This article reassesses the foreign policy legacy of George W. Bush in light of the emerging historical record of his administration. We conclude that, whereas Bush’s foreign policy was in widespread disrepute when he left office in 2009, that reputation is likely to improve – perhaps significantly – in the coming years. We identify six particular arguments that lend credence to an emerging ‘Bush revisionism.’ To be clear, we do not necessarily argue that the balance sheet on Bush’s foreign policy was positive, but the arguments presented here are likely to generate a more sympathetic and favorable historical assessment of Bush’s presidency over time.  相似文献   
120.
It is shown that when X is an arbitrary finite subset of an n-factor product set and preference relations on each factor or criterion are assumed only to be asymmetric, efficient (undominated) points always exist in the set P of probability distributions on X when the preference relations are extended to probability distributions on the factors according to SSB utility theory. Thus, arbitrary finite structures and potentially cyclic preferences do not present a problem for the theory of efficiency under the convexification-extension procedure.  相似文献   
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