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41.
This paper analyzes, from a game-theoretic standpoint, the simultaneous choice of speeds by a transitor and by an SSK which patrols back and forth perpendicular to the transitor's course. Using idealized acoustic assumptions and a cookie-cutter detection model which ignores counterdetection, we are able to present the problem as a continuous game, and to determine an analytic solution. The results indicate that with these assumptions, there are conditions under which neither a “go fast” nor a “go slow” strategy is optimal. The game provides a good example of a continuous game with a nontrivial solution which can be solved effectively.  相似文献   
42.
The component placement problem is a specialization of the quadratic assignment problem that has been extensively studied for a decade and which is of considerable practical value. Recently, interest in component placement algorithms has risen primarily as a result of increased activity in the field of computer-aided design automation. This paper deals with the methodology of component placement and is based on the results of considerable operational experience. A tutorial presentation of tree search placement algorithms is provided, and an improved placement procedure is described which is demonstrated to be effective in generating near optimal solutions to the component placement problem. These solutions are completely reproducible and are obtained at an acceptable expenditure of computational resources. An additional objective is an assessment of performance of the class of near optimal algorithms. In particular, the question- how close to optimal are the near optimal solutions- is examined.  相似文献   
43.
This paper has been presented with the Best Paper Award. It will appear in print in Volume 52, No. 1, February 2005.  相似文献   
44.
The human visual system is still an important factor in military warfare; military personnel receive training on effective search strategies, and camouflage that can effectively conceal objects and personnel is a key component of a successful integrated survivability strategy. Previous methods of camouflage assessment have, amongst others, used psychophysics to generate distinctiveness metrics. However, the population from which the human observers are drawn is often not well defined, or necessarily appropriate. In this experiment we designed a new platform for testing multiple patterns based on a camouflaged object detection task, and investigate whether trained military observers perform better than civilians. We use a two-alternative forced choice paradigm, with participants searching images of woodland for a replica military helmet displaying Olive Green, Multi Terrain Pattern, US Marine Pattern or, as a conspicuous control, UN Peacekeeper Blue. Our data show that there is no difference in detection performance between the two observer groups but that there are clear differences in the effectiveness of the different helmet colour patterns in a temperate woodland environment. We conclude that when tasks involve very short stimulus presentation times, task-specific training has little effect on the success of target detection and thus this paradigm is particularly suitable for robust estimates of camouflage efficacy.  相似文献   
45.
The criticism of James, Solberg and Wolfson (JSW) (1999) by Oneal and Russett (OR) is not responsive to the methodologica] issues at stake. JSW argued that war is an endogenous feature of the world political and economic system. If its causes are to be measured, it must be as a structural equation in a simultaneous system. Wedded to the idea that “democracies never fight each other,” OR rely on a single equation to justify their view. JSW claim that such an equation may be an ad hoc reduced form with no causal implications unless the equation is explicitly identified as a structural equation. JSW expand the model to explain democracy and conflict as two endogenous variables. JSW do not claim to have discovered the true relationships between these variables by their minimal expansion of the structural relation. They do show that unless these (and other) variables are treated as part of a system, the results are unstable, contradictory, of minimal size and not a reliable guide to public policy.  相似文献   
46.
47.
‘Doctrine’ has been part of military vernacular for at least a century. Nonetheless, it is a concept which is rather under-explored. The aim of this article is thus to break doctrine down into its component parts in order to grasp what a military doctrine actually is. Thereafter, the article points out different ways to utilise doctrine as a military devise. A doctrine cannot be, or rather should not be, all things to all men. On the contrary, doctrine can be a tool of command, tool of education or a tool of change. The main upshot of the article is that the future of doctrine is far brighter than its critics want us to believe.  相似文献   
48.
Highly fragmented insurgencies often lack explicit coordination mechanisms such as plans, direct means of communication, or hierarchical organization. Many such insurgencies nevertheless obtain a high degree of coordination that produces strategic-level effects. This article presents a theory of how coordination can emerge tacitly in highly fragmented insurgencies, and how this can produce strategic-level effects. Strategic effects emerge through a combination of complementary and supplementary tactical-level actions between commonly positioned insurgent groups. The theory is then tested again evidence from the Soviet–Afghan War. The evidence presented shows that some of the Mujahidin's strategic-level effectiveness was produced through tacit coordination.  相似文献   
49.
50.
Brian Johnson, The Secret War. London: BBC, 1978. Pp. 352; £6.50.

R. V. Jones, Most Secret War: British Scientific Intelligence 1939–45. London: Hamish Hamilton, 1978. Pp. xx + 556; £7.95.

Solly Zuckerman, From Apes to Warlords 1904–46. London: Hamish Hamilton, 1978. Pp. 00 (Information not available from publisher); £8.50.

Adrian Preston, ed., General Staffs and Diplomacy before the Second War. London: Croom Helm, 1978. Pp. 138; £5.95.

W. G. F. Jackson. ’Overlord’: Normandy 1944. London: Davis Poynter, 1978. Pp. 250; £6.75.

Richard K. Betts, Soldiers, Statesmen, and Cold War Crises. Cambridge, Mass. and London: Harvard University Press, 1977. Pp. 292 + index + appendices; Np.

Gerard J. Mangone, Marine policy for America—The United States at Sea. Lexington, Mass.: Lexington Books, 1977. Pp. 370, £17.50.

F. M. Richardson, Fighting Spirit. London: Leo Cooper, 1978. Pp. 189 + xv; £7.50.

Allen R. Millet, Ed., A Short History of the Vietnam War. London &; Bloomington: Indiana University Press, 1978. Pp. 169; £2.75.

Robert P. Berman, Soviet Airpower in Transition. Washington: Brookings, 1978. Pp. 82; $2.95 (Paper).  相似文献   
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