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211.
This paper reviews recent developments among African regional organisations in undertaking peacekeeping operations, as well as in preparing for future missions. It focuses on those that have been the most active: the Organisation of African Unity/African Union, the Economic Community of West African States and the Southern African Development Community. The paper goes on to briefly describe and analyse the activities of the French, UK, and US capacity-building programmes designed to develop African peacekeeping capacities. The author then identifies some specific concerns and recommends actions to help meet today's challenges. The paper concludes with a short analysis of African organisations' capacities and proclivities to provide a peacekeeping force for Sudan.  相似文献   
212.

This paper experimentally tests a number of hypotheses that follow from models of international competition that are based on Tullock style rent‐seeking models. Specifically, we designed and performed experiments to see how variations in the degree of publicness in the prize as well as changes in the values assigned to the prize affect alliances in terms of individual nation contributions, total contributions, burden sharing, and the likelihood of winning the prize. While there was substantial variation in individual behavior, the results of the experiments generally conform to the theoretical predictions of the rent‐seeking model of international competition and alliances.  相似文献   
213.
In discussing China's January 2007 hit-to-kill intercept of the Chinese weather satellite FengYun-1C, most American analysts sought the “message” for the United States—either by asserting that China's test was a deliberate step toward a comprehensive counterspace capability to offset U.S. conventional military superiority or an attempt to force the United States to the negotiating table on “the prevention of an arms race in outer space.” Chinese officials, after a long silence, eventually claimed the test was an “experiment” that was “not targeted at any country.” We traveled to China several times in 2007 and had a series of conversations with Chinese individuals knowledgeable about the history of this particular antisatellite program and with access to information about the decision-making process prior to and after the final test. These discussions were off the record, not for attribution, given the sensitivity of the subject. They reflected the views of some of the key institutions involved in the test from the State, the Communist Party, the People's Liberation Army, and aerospace experts involved in debris calculations. The information conveyed to us suggests that American commentators tend to place much greater importance on the United States as a driver in China's decision to develop the technology and conduct the test than do the Chinese.  相似文献   
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This article concerns the scheduling of n jobs around a common due date, so as to minimize the average total earliness plus total lateness of the jobs. Optimality conditions for the problem are developed, based on its equivalence to an easy scheduling problem. It seems that this problem inherently has a huge number of optimal solutions and an algorithm is developed to find many of them. The model is extended to allow for the availability of multiple parallel processors and an efficient algorithm is developed for that problem. In this more general case also, the algorithm permits great flexibility in finding an optimal schedule.  相似文献   
216.
Book reviews     
Soviet Nuclear Strategy from Stalin to Gorbachev: a Revolution in Soviet Military and Political Thinking. By Honore M. Catudal. Mansell, London (1988), ISBN 0–7201–2000–4, £25.00

The Military: More Than Just a Job? Edited by Charles C. Moskos and Frank R. Wood. Pergamon‐Brassey's, London (1988), ISBN 0–08–034321‐X, £17.00 ($30.00)

Douglas Haig, 1861–1928. By Gerard J. de Groot. Unwin Hyman, London (1988), ISBN 004 4401922, £20.00

Defence Policy Making. A Comparative Analysis. Edited by G. M. Dillon. Leicester University Press, Leicester (1988), ISBN 0–715–1268–5, £10.95

The Future of U.K. Air Power. Edited by P. Sabin. Brassey's, London (1988), ISBN 0–08–035825‐X (hardcover), 0–08–036256–7 (flexicover), hardcover £18.95 ($34.00), flexicover £9.95 ($17.95)  相似文献   

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In this paper marginal investment costs are assumed known for two kinds of equipment stocks employed to supply telecommunications services: trunks and switching facilities. A network hierarchy is defined which includes important cases occurring in the field and also appearing in the literature. A different use of the classical concept of the marginal capacity of an additional trunk at prescribed blocking probability leads to a linear programming supply model which can be used to compute the sizes of all the high usage trunk groups. The sizes of the remaining trunk groups are approximated by the linear programming models, but can be determined more accurately by alternate methods once all high usage group sizes are computed. The approach applies to larger scale networks than previously reported in the literature and permits direct application of the duality theory of linear programming and its sensitivity analyses to the study and design of switched probabilistic communications networks with multiple busy hours during the day. Numerical results are presented for two examples based on field data, one of which having been designed by the multi-hour engineering method.  相似文献   
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