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191.
If one could look through the familiar artificial political lines and colors of a current world map into the twenty-first century strategic reality, one could see a complex new security arena. A deeper look into that picture would provide magical snapshots that show several types of ambiguous and asymmetric conflicts, and state failure - and their causes and consequences. Then, with some additional adjustments of focus, one can discern a number of issues that cannot be shown in two-dimensional space. They are briefly discussed as follows. First and importantly, one can get a better idea of the complex threat situation and the ultimate threat - state failure. Second, an even deeper examination of the vision of contemporary wars reveals the shadows of things that have been and of those that will be on the road ahead. Third, a closer look at the familiar and troubling world map exposes some signposts on the road ahead that indicate the most significant changes in the landscape. Finally, our magical microscope reveals a short list of the basic challenges and tasks that can help discerning civilian and military leaders negotiate the road through the new global security environment.  相似文献   
192.
We develop and estimate optimal age replacement policies for devices whose age is measured in two time scales. For example, the age of a jet engine can be measured in the number of flight hours and the number of landings. Under a single‐scale age replacement policy, a device is replaced at age τ or upon failure, whichever occurs first. We show that a natural generalization to two scales is to replace nonfailed devices when their usage path crosses the boundary of a two‐dimensional region M, where M is a lower set with respect to the matrix partial order. For lifetimes measured in two scales, we consider devices that age along linear usage paths. We generalize the single‐scale long‐run average cost, estimate optimal two‐scale policies, and give an example. We note that these policies are strongly consistent estimators of the true optimal policies under mild conditions, and study small‐sample behavior using simulation. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 592–613, 2003.  相似文献   
193.
In this paper, confidence intervals are given for two quantities of importance related to renewal processes. For each quantity, two confidence intervals are discussed. One confidence interval is given for general, all‐purpose use. Another confidence interval is given which is easier to compute, but not of general use. The case where data are subject to right censorship is also considered. Some numerical comparisons are made. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 638–649, 2003.  相似文献   
194.
We present transient and asymptotic reliability indices for a single‐unit system that is subject to Markov‐modulated shocks and wear. The transient results are derived from the (transform) solution of an integro‐differential equation describing the joint distribution of the cumulative degradation process and the state of the modulating process. Additionally, we prove the asymptotic normality of a properly centered and time‐scaled version of the cumulative degradation at time t. This asymptotic result leads to a simple normal approximation for a properly centered and space‐scaled version of the systes lifetime distribution. Two numerical examples illustrate the quality of the normal approximation. © 2009 Wiley Periodicals, Inc. Naval Research Logistics 2009  相似文献   
195.
Intrastate conflicts, long eclipsing interstate conflicts, are often internationalized. This paper examines internationalized intrastate conflicts through the types of both the intervening and the embattled regimes. Do democracies, more or less than autocracies, support autocratic governments in their fights against rebels? This paper tests three hypotheses: (1) democracies support autocrats fighting rebels less than autocracies do. (2) Democracies support democratic governments fighting against rebels more than autocracies do. (3) The more democratic two states are, the higher the probability one would support the other’s fight against rebels. Covering all documented external support in intrastate wars (1975–2000), our findings support hypothesis one and two only partly and confirm hypothesis three. However, comparing the two major accounts of the Democratic Peace theory (DPT)—the normative and the structural—our findings corroborate only the former robustly. The paper thus helps enriching the insights of the DPT beyond interstate conflicts.  相似文献   
196.
ABSTRACT

China’s efforts to build a ‘new type of great power relations’ and a ‘new type of military-to-military relations’ do not constitute a major turning point in relations with the United States. Political relations set limits on military cooperation, and the two sides have been unable to construct a sustainable strategic basis for relations. This has contributed to an ‘on-again, off-again’ pattern in military ties. Trends show a pattern of frequent disruptions in military-to-military relations from 2000 to 2010, followed by an increase in interactions beginning in 2012. Nevertheless, obstacles on both sides are likely to limit mutual trust and constrain future development of military-to-military relations.  相似文献   
197.
On the surface of a sphere, we take as inputs two points, neither of them contained in any of a number of spherical polygon obstacles, and quickly find the shortest route connecting these two points while avoiding any obstacle. The WetRoute method presented here has been adopted by the US Navy for several applications. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 63: 374–385, 2016  相似文献   
198.
199.
NATO officials have cited various reasons for conducting their air campaign in Kosovo. Though not emphasised as much, the concern that NATO's credibility was at stake stood out as the most paramount on the basis of logical comparison. In fact, NATO intervened in Kosovo primarily to maintain its credibility as the Trans- Atlantic's only multilateral security mechanism because its continued existence depended on it. While NATO's search for its new role in the post-Cold War strategic environment has been fraught with several problems, the inclination towards collective security and crisis management has placed it in a position of proactive military obligation. Predictably, NATO's venture in the Balkans this time around has had various implications on its future prospects as an organisation.  相似文献   
200.
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