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This article outlines Chinese strategic nuclear forces and the Chinese philosophical approach to nuclear security. It then focuses on the domestic conditions in China which could precipitate vulnerabilities to its nuclear forces. From information about internal security conditions in China, specific internal threats to Chinese nuclear security will be derived. Based on these threats, several outsider and insider scenarios will be outlined involving a variety of terrorist or terrorist related behaviors. These notional scenarios will include everything from overrun or attack, to diversion, to cyber terrorism, to sabotage. The article will then cover what these scenarios and the possible Chinese reaction to them may mean for the security, military and diplomatic strategies of the United States.  相似文献   
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This article examines the reassessment of U.S. strategy that Dwight D. Eisenhower directed after replacing Harry S. Truman in the White House in January 1953, as he worked to bring the Korean War to an end and then confronted the problems remaining in its aftermath. Despite much of the rhetoric of the early Eisenhower administration, the outcome of that reassessment fit more closely the objective of containment than key strategic formulations of its predecessor. Why was this so? How did the orientation apply to ending the war in Korea and sustaining the U.S. position there and elsewhere after the armistice? What insights, if any, do the process of reassessment and its outcome provide for the present? Answers to these questions serve to emphasize the dynamic and contingent nature of American strategy in the early Cold War and the importance of flexible, engaged leadership in the White House.  相似文献   
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Following its encounter with insurgent violence in Iraq, the U.S. Department of Defense (DoD) has sought to improve the U.S. military's ability to conduct counterinsurgency. This effort suggests a potential turning-point in the history of the U.S. military, which has traditionally devoted its attention and resources to “high-intensity” or “conventional” combat. Given this institutional culture, what are now the prospects of the U.S. military ‘learning counterinsurgency’? In many ways, the ongoing reorientation is promising and targeted, informed directly by the U.S. campaign in Iraq. At the same time, Pentagon priorities still reveal a remarkable resistance to change, and this in spite of the radically altered strategic environment of the War on Terror. Given this intransigence - and the eventual fall-out from the troubled Iraq campaign - the ongoing learning of counterinsurgency might very well fail to produce the type of deep-rooted change needed to truly transform the U.S. military.  相似文献   
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Research into fingermark enhancement techniques has traditionally used visual comparisons and qualitative methods to assess their effectiveness based on the quality of the developed fingermark. However, with increasing research into the optimisation of these techniques the need for a quantitative evaluative method has arisen. Parameters for acceptable fingerprint quality are not well defined and generally encompass clear, sharp edges and high levels of contrast between the fingermark ridges and background material. Using these current parameters, a conclusive measurement of fingerprint quality and thus the effectiveness of development techniques cannot be achieved.This study presents a model through which an aspect of fingerprint quality can be objectively and impartially measured based on a relative contrast index, constructed through measuring the reflective intensity of the fingermark ridges against the background material. Using a fibre-optic spectrophotometer attached to a microscope with axial illumination, the intensity counts of the ridge detail and background material were measured and a logarithmic contrast index constructed. The microscope and spectrophotometer parameters were experimentally tested using a standard colour resolution chart with known reflective properties. The protocol was successfully applied to four sample groups: black inked fingerprints on white paper; latent fingermarks on white paper developed separately with ninhydrin and physical developer; and fingermarks in blood deposited on white tiles and enhanced with amido black. The contrast indices obtained quantitatively reflect the level of contrast and provide an indication of fingerprint quality through a numerical representation rather than previous qualitative methods. It has been suggested that the proposed method of fingerprint quantification may be viable for application in the forensic research arena as it allows the definitive measurement of contrast to aid the evaluation of fingermark detection and enhancement techniques.  相似文献   
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This article aims to delineate several issues raised by an historically based approach to understanding the present and the future. Beginning with a discussion of the profound impact that drastic changes have had on the international environment, the article then outlines what history suggests about human nature's influence on the course of future events; the future of war; the nature of governance and the United States. This essay does not attempt to provide answers, but rather suggests how policy makers, strategists, and military leaders might think through the complex political and cultural questions they need to be asking in the making of strategy. This is the essential first step for Americans. If they fail to ask the right questions, most answers will prove irrelevant to the challenges of the future.  相似文献   
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During the past two decades Nigeria has invested heavily in scientific research, by developing country standards. Yet these investments at best have had only marginal impacts on the activities of the production and service sectors even though there are many priority development activities which could benefit from inputs from Nigerian researchers. At the national level efforts to direct or even co-ordinate the planning and budgeting of research have been seriously hampered by frequent changes in organizational responsibilities and by repeated budget cuts. Historically, the activities of the federal research institutes have been poorly tuned to the interests and capabilities of the potential users of their research products. Neither these institutes nor the universities with research activities are in a position to develop products or processes which can compete with imported technologies that are saturating the economy. However, the research institutes, and to a lesser extent the universities, should make greater contributions in applying science to improved use of the nation's natural resource endowments, although significant changes in research management at the project level are needed if this objective is to be realized. The Government should provide incentives to the multinational companies operating in Nigeria to develop joint programmes with the research institutes and universities as one mechanism for diffusing the administrative and technical capabilities of the companies. Meanwhile, selected public sector enterprises should be encouraged to expand technological innovation efforts which could be directly applied to their production activities.  相似文献   
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