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211.
The United States has multiple nuclear detection initiatives to secure against a terrorist nuclear attack, including the Container Security Initiative, installation of radiation detectors at U.S. border points of entry, and establishment of the Domestic Nuclear Detection Office (DNDO). The current nuclear detection system architecture falls short of being able to reliably catch fissile nuclear material in transit, specifically shielded Highly Enriched Uranium (HEU) and Plutonium (Pu), both within the US and abroad. Checkpoints at border crossings can be circumvented, and no adequate system is under development to deter the transport of fissile materials. Using nuclear link-budget calculations, we show why a network relying primarily on handhelds, fixed detectors, and portals is not sufficient. We examine the technical, economic, and operational feasibility of a comprehensive national network incorporating in-vehicle detectors to reliably detect and deter the transport of fissile material inside the vehicle itself.  相似文献   
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This paper investigates theoretically and empirically the determinants of military spending in Africa. It specifies a formal model and uses time‐series and cross‐sectional estimations to ascertain the reasons behind variations in military allocations across and within 40 African countries during 1960–1991. The differences in military expenditures appear to reflect a complex of economic, political, and strategic factors at both national and international levels. Strategic considerations are, however, found to be the most important factors in most African countries.  相似文献   
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Numerous writers have acknowledged the importance of radio communications and hate propaganda in the Liberian civil war (1990–1997), but none have explored the subject in depth. A wide variety of related issues have been neglected, including military efforts to seize control of broadcast facilities, the deliberate manipulation of public information and perceptions, and the implications of both for wartime atrocities and post-war justice. In the following essay, I identify and discuss six general strands of thought on guerrilla radio broadcasting and communications in wartime Liberia. The first looks to the relationship between mass media and the state in the pre-civil war era. The second covers the cooption of the wartime free press. Three further themes – Charles Taylor's cultivation of personal power, the relevance of broadcasting for rebel command and control capabilities, and Taylor's media dominance during the 1997 Presidential campaign – demonstrate the strategic and public roles of radio communications and broadcasting. Finally, I look to written survivor memoirs for elite responses to wartime media monopolies, guerrilla propaganda, and psychological warfare. I conclude with some notes on indicators for future research, and their implications for historical and contemporary issues in Liberia.  相似文献   
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Building upon a far-reaching reform movement carried out during the administration of Andres Pastrana (1998–2002), the Colombian military emerged in the Alvaro Uribe first term (2002–06) as a powerful, flexible organization capable of implementing a national strategy for successful counterinsurgency. Sweeping organizational change was accompanied by advances in operational art and tactics, as well as the promotion of new leadership tested in combat. A growing maturity in civil–military relations enabled national advances in democratic politics, economic progress and state integration, the latter to a degree unprecedented in Colombian history.  相似文献   
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Abstract

In 2011 a wave of revolutionary movements, the so-called Arab Spring, spread in the Middle East and North Africa. Libya was one of the most affected countries, ending Gaddafi’s dictatorship after an international intervention and a civil war. This paper assesses the effects that this revolution had on Libyan economy. The analysis is made by means of the synthetic control method. Our estimates for the 2011–2014 period show (i) a cumulative loss in the growth rate of per capita real GDP of 64.15%; (ii) a cumulative loss in per capita real GDP of 56,548 dollars; and (iii) a cumulative loss in the aggregate real GDP of 350.5 billion dollars.  相似文献   
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Technologically advanced aircraft rely on robust and responsive logistics systems to ensure a high state of operational readiness. This paper fills a critical gap in the literature for combat models by closely relating effectiveness of the logistics system to determinants of success in combat. We present a stochastic diffusion model of an aerial battle between Blue and Red forces. The number of aircraft of Blue forces aloft and ready to be aloft on combat missions is limited by the maximum number of assigned aircraft, the reliability of aircraft subsystems, and the logistic system's ability to repair and replenish those subsystems. Our parsimonious model can illustrate important trade‐offs between logistics decision variables and operational success.  相似文献   
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