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481.
This paper considers the scheduling problem to minimize total tardiness given multiple machines, ready times, sequence dependent setups, machine downtime and scarce tools. We develop a genetic algorithm based on random keys representation, elitist reproduction, Bernoulli crossover and immigration type mutation. Convergence of the algorithm is proved. We present computational results on data sets from the auto industry. To demonstrate robustness of the approach, problems from the literature of different structure are solved by essentially the same algorithm. © 1999 John Wiley & Sons, Inc. Naval Research Logistics 46: 199–211, 1999  相似文献   
482.
    
ABSTRACT

Russian political leaders and military strategists are growing increasingly concerned about “strategic conventional weapons”—a broad category that appears to include all non-nuclear, high-precision, standoff weapons—and about long-range, hypersonic weapons, in particular. These concerns are complex and multifaceted (and, in some cases, contradictory), but chief among them are the beliefs that strategic conventional weapons could prove decisive in a major conflict and that Russia is lagging behind in their development. US programs to develop and acquire such weapons—namely, the Conventional Prompt Global Strike program—are of great concern to Russian strategists, who argue both that the United States seeks such weapons for potential use against Russia—its nuclear forces, in particular—and because strategic conventional weapons are more “usable” than nuclear weapons. Asymmetric responses by Russia include increased reliance on tactical nuclear weapons, efforts to enhance the survivability of its nuclear forces, and investments in air and missile defenses. There is also strong—but not completely conclusive evidence—that Russia is responding symmetrically by attempting to develop a long-range, conventionally armed boost-glide weapon.  相似文献   
483.
484.
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   
485.
From 1956 to 1960, the French Army developed a force of Muslim auxiliaries (supplétifs) as a major component of its strategy to combat the National Liberation Front (FLN) insurgency in Algeria. Aside from their military utility in hunting down the guerrillas in the mountains and forests, the supplétifs were instrumental in undermining FLN legitimacy in the countryside. The rapid growth and employment of the supplétif force dismantled FLN political control in the villages, undermined the enemy's unity, and critically weakened the revolutionaries' claim to represent all of Algeria's Muslims. The military and political activities of France's Muslim soldiers also projected an image of Muslim–European unity behind the French cause, and portrayed the French Army as the only legitimate political force in numerous villages. These political successes, however, were limited to the local, tactical level of revolutionary warfare, and the Army was never able to convert the supplétifs into a force of decisive, strategic political significance. They thus had little ultimate impact on the outcome of the conflict.  相似文献   
486.
    
As a consequence of intervention in Iraq and Afghanistan, force ratio for counterinsurgency (COIN) has come under increased scrutiny. Reduced to its essence, the issue is simply, ‘How many troops does it take to get the job done?’ This answer has been sought by the US military, academia, and think tanks. There have been numerous responses, culminating in several ‘plug-and-play’ equations for minimum force ratios in COIN operations. Due to the impossibility of determining precisely how many insurgent forces there are, it has become common to base force ratios on the population of the country. In the realm of policy, the question above is posed as, ‘How many of our troops does it take to get the job done?’  相似文献   
487.
    
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   
488.
    
This article provides an in-depth examination and analysis of the 2006–2009 Tuareg rebellion in Mali and Niger. It identifies the underlying reasons behind the rebellion, explores contrasting counter-insurgency (COIN) strategies employed by the two governments, and presents some lessons learned. While both COIN approaches ultimately produced similar peace settlements, the article argues that the Malian strategy of reconciliation combined with the selective use of force was far more effective than the Nigerien iron fist approach at limiting the size and scope of the insurgency and producing a more sustainable peace. It concludes by looking at the role of external actors, particularly the United States, and how the failure to internationalize the conflict was actually more beneficial to the local COIN effort, as well as to the longer strategic interests of the United States in the region.  相似文献   
489.
    
Accelerated life testing (ALT) using multiple stresses is commonly used in practice to resemble the operating stresses at normal operating conditions and obtain failure observations in a much shorter time. However, to date, there is little research into the theory of planning ALT for reliability estimation with multiple stresses. ALT with multiple stresses can result in a large number of stress‐level combinations which presents a challenge for implementation. In this article, we propose an approach for the design of ALT plans with multiple stresses and formulate multistress test plans based on different objectives and practical constraints. We develop a simulated annealing algorithm to efficiently determine the testing plan parameters. We demonstrate the proposed method with examples based on an actual test conducted using three stress types. The obtained optimal test plans are compared with those based on fractional factorial design. © 2013 Wiley Periodicals, Inc. Naval Research Logistics 60: 468–478, 2013  相似文献   
490.
    
In the aftermath of Israel's stunning victory over Egyptian, Jordanian and Syrian forces during the 1967 Six-Day War, accolades for the victory were often showered upon the Israeli Air Force (IAF). Indeed, many believed that it had been Israeli air power that had been the decisive element in the war by first eliminating the Arab air forces and then obliterating the Arab armies in turn. While the IAF did play an extremely important role in the fighting, it was not the decisive element of Israeli victory, and its impact was felt in very different ways from the common perception. Indeed, an appreciation of the true role of Israeli air power in the war reinforces both the importance of psychological factors in combat, and the ability of air forces to have a psychological impact disproportionate to their physical impact.  相似文献   
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