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71.
From the Barents and the Baltic Sea in the north, through Central Europe and the Balkans, to the Black Sea in the south a range of new subregional groups and cooperation processes have emerged in Europe during the 1990s. Compared to NATO and the European Union, these new subregional groups have received little attention. Their ‘indirect approach’ to security, however, plays an important role in overcoming the legacy of the Cold War, reducing the risks of military conflict and addressing non‐military security challenges. As NATO and the EU expand eastwards, subregionalism is assuming growing importance as a means of avoiding new ‘dividing lines’ in Europe. After the wars in Bosnia and Kosovo, subregionalism is also gaining importance as a means of building cooperation in South‐Eastern Europe. The challenge for the future is to give more substance and depth to Europe's new subregional cooperation frameworks.  相似文献   
72.
The Fisher naval revolution of 1904–10 represented a deliberate attempt to achieve defense transformation to bolster Britain's pretensions to global naval supremacy. The vision called for smaller, more capable forces to do the work of larger, more expensive conventional formations. It consisted of three main elements. First, the replacement of the traditional station fleet system for protecting overseas interests by rapid deployment forces comprised of battlecruisers that could be ‘maneuvered’ by wireless to combat specific enemy threats. Second, at home, instead of a sea control strategy based upon a superior battle-fleet, a sea denial strategy based on flotilla defense commanded and controlled from London via wireless. The third element of the Fisher revolution depended upon ‘plunging’, or shaping and directing technological change through a special relationship with armaments firms. A sophisticated information-communications network was integral to the revolution.  相似文献   
73.
Politicians, political pundits, and others focus a lot of attention on the political militias in Iraq, usually blaming them for their destabilising effect on the country and insisting that they disband. This study examines the impact that the militias in Iraq have on the Iraqi government's ability to consolidate control over its territory by first explaining how militias rose to prominence in Iraq during the power vacuum created by Saddam Hussein's ousting, then analysing the many ways militias adversely impact the security situation. The study then examines the other side of the argument – that is, why militias enjoy so much support in Iraq among their constituencies, and why they may actually be necessary to achieve stability in Iraq in the short term.  相似文献   
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ABSTRACT

This paper challenges recent claims that competitive market dynamics incentivize Private Military and Security Companies (PMSCs) to fully commit to providing effective services, thereby reducing the duration of civil war. Our assessment of a most-likely case scenario for this argument – Sierra Leone – reveals four critical problems. First, there is rarely direct competition, even if numerous companies are present. Second, the presence of multiple PMSCs usually represents a collaboration among subsidiaries providing distinct services, often under the same corporate umbrella. Third, data aggregation obfuscates the overlap of PMSC presence, inflating the amount of perceived competition. Finally, we raise concerns regarding how quantitative analyses can conflate conflict intensity with conflict termination.  相似文献   
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Contained herein is an informal nonmathematical survey of research in multi-echelon inventory theory covering published results through 1971. An introductory section defines the term, “multi-echelon,” and establishes the kinds of problems involving multi-echelon considerations. Subsequent sections provide surveys of research on deterministic and stochastic multi-echelon inventory control problems, allocation models, and multi-echelon planning and evaluation models. A final section discusses the present state of the art and suggests directions for future research. A bibliography of papers concerning multi-echelon inventory theory and applications is included.  相似文献   
77.
The transportation model with supplies (Si) and demands (Di) treated as bounded variables developed by Charnes and Klingman is extended to the case where the Si and Di are independently and uniformly distributed random variables. Chance constraints which require that demand at the jth destination will be satisfied with probability at least βi and that stockout at the ith origin will occur with probability less than αi are imposed. Conversion of the chance constraints to their linear equivalents results in a transportation problem with one more row and column than the original with some of the new arcs capacitated. The chance-constrained formulation is extended to the transshipment problem.  相似文献   
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Research and development activities in a business firm or government laboratory are portrayed as a multi-stage information generation and conversion process. A “basic research” phase generates opportunities, in the form of findings in a set of scientific disciplines, which are available for subsequent exploitation. It is assumed that increments to information in a subject area are stochastic, proportional to the amount of knowledge which already exists in the area, and have values which are randomly distributed. An “exploratory development” phase is viewed as a process of selecting a subset of alternative research opportunities, improving each opportunity in the direction of its applications, estimating the value of the improved opportunity and using these estimates to choose the exploratory development results to be implemented in engineering development. The “engineering development” phase makes the value of exploratory results realizable without changing value or risk. Engineering development costs are assumed to increase as value increases. If exploratory development is not successful, additional costs in engineering development must be incurred to bring the design up to a minimum desirable level. The model is intended as a step toward formulating and analyzing problems in management planning and control of the several interrelated stages of the research and development process.  相似文献   
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