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We consider two opponents that compete in developing asymmetric technologies where each party's technology is aimed at damaging (or neutralizing) the other's technology. The situation we consider is different than the classical problem of commercial R&D races in two ways: First, while in commercial R&D races the competitors compete over the control of market share, in our case the competition is about the effectiveness of technologies with respect to certain capabilities. Second, in contrast with the “winner‐takes‐all” assumption that characterizes much of the literature on this field in the commercial world, we assume that the party that wins the race gains a temporary advantage that expires when the other party develops a superior technology. We formulate a variety of models that apply to a one‐sided situation, where one of the two parties has to determine how much to invest in developing a technology to counter another technology employed by the other party. The decision problems are expressed as (convex) nonlinear optimization problems. We present an application that provides some operational insights regarding optimal resource allocation. We also consider a two‐sided situation and develop a Nash equilibrium solution that sets investment values, so that both parties have no incentive to change their investments. © 2012 Wiley Periodicals, Inc. Naval Research Logistics 59: 128–145, 2012  相似文献   
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This paper studies combat between two homogeneous forces modelled with variable-coefficient Lanchester-type equations of modern warfare with supporting fires not subject to attrition. It shows that this linear differential-equation model for combat with supporting fires may be transformed into one without the supporting fires so that all the previous results for variable-coefficient Lanchester-type equations of modern warfare (without supporting fires) may be invoked. Consequently, new important results for representing the solution (i.e. force levels as functions of time) in terms of canonical Lanchester functions and also for predicting force annihilation are developed for this model with supporting fires. Important insights into the dynamics of combat between two homogeneous forces with such supporting fires are discussed.  相似文献   
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This article aims to review some of the key lessons learnt by the Royal Ulster Constabulary's (RUC) Special Branch in the 37 years of the troubles in Northern Ireland. Above all counter-terrorism is an intelligence led operation and Special Branch are the key agency for this in all UK police forces, who have now benefited enormously from the expertise that the RUC's Special Branch built up over the years and have passed on to their colleagues throughout the UK. Intelligence is more often than not a human role and relies on human agencies, which was the case in Northern Ireland. The bulk of intelligence gathering was carried out at quite low levels although the sifting and analysing of it became a more specialist skill. Electronic intelligence and computerised systems were often quite low down in the order of priorities and uses, which tends to confound popular impressions. Agents, informers and good old fashioned ‘coppers’ who knew their patch were much more important both in terms of gathering information and in terms of undermining the terrorists morale from within and it was these factors that fundamentally defeated the IRA in Northern Ireland.  相似文献   
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Peter Trubowitz, Defining the National Interest: Conflict and Change in American Foreign Policy. Chicago and London: University of Chicago Press, 1998. Pp.xvi + 353, biblio., figs, maps, index. $55 (cloth); $18.95 (paper). ISBN 0–226–81302–9.  相似文献   
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James Meernik 《Civil Wars》2015,17(3):318-339
Research on human rights treaties has mostly reached depressingly similar conclusions – that such treaties and their resulting institutions have little or no impact on human rights. The International Criminal Court, however, possesses significant power to investigate and prosecute violations of international law that equip it with potentially more influence than previous human rights regimes. I suggest, however, that the impact of the ICC on human rights is conditioned by signatory governments’ commitment to good governance and acceptance of the role of the ICC in addressing violations of international law. I develop a two-stage model of ICC ratification and human rights abuse that shows that while many states have ratified the ICC Treaty, not all are committed to stopping the crimes under its jurisdiction. Rather, state commitment to human rights depends first on its commitment to the rule of law within its own borders. Second, commitment to human rights depends on states’ willingness to grant the ICC the powers necessary to carry out its mission. Through a number of statistical tests, I find strong support for these hypotheses on states’ human rights and propensity for violence.  相似文献   
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An availability‐oriented approach has been developed to decide when to replace an aging system. For an existing system, it is optimal to operate another year if and only if the incremental cost per available year is less than the lifetime average cost per available year of a new aircraft. We illustrate our approach using United States Air Force KC‐135 tanker data. In demonstrating our approach, we find it will be optimal to replace the KC‐135 by the end of the decade.  相似文献   
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