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341.
In this article we consider the unweighted m-center problem with rectilinear distance. We preent an O(nm–2 log n) algorithm for the m-center problem where m ≥ 4.  相似文献   
342.
Book Reviews     
Strategic Geography. By Hugh Faringdon. Routledge, London (1989), ISBN 0-415-00980-4, £40.00

Field Artillery and Firepower. By J. B. A. Bailey. The Military Press, Oxford (1989), ISBN 0-85066-810-7, £25.00 (hardback), ISBN 0-85066-811-5, £14.50 (paperback)

U.S.-Soviet Security Cooperation. Edited by Alexander L. George, Philip J. Farley and Alexander Dallin. Oxford University Press, New York (1988), ISBN 0-19-505397-4, £30.00 (hardback), $19.95 (paperback)

Non-production by Industry of Chemical-warfare Agents: Technical Verification under a Chemical Weapons Convention. Edited by S. J. Lundin. SIPRI/Oxford University Press, Oxford (1988), ISBN 0-19-829129-9, £19.50

Ireland's Terrorist Trauma: Interdisciplinary Perspectives. Edited by Alan O'Day and Yonah Alexander. Harvester Wheatsheaf, Hemel Hempstead (1989), ISBN 7450-049003, £27.50 ($48.65)

Pilots and Rebels: the Use of Aircraft in Unconventional Warfare 1918-1988. By P. A. Towle. Brassey's (UK), London (1989), ISBN 0-08-036712-7, £29.95 ($53.95)  相似文献   
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Consider an experiment in which only record-breaking values (e.g., values smaller than all previous ones) are observed. The data available may be represented as X1,K1,X2,K2, …, where X1,X2, … are successive minima and K1,K2, … are the numbers of trials needed to obtain new records. We treat the problem of estimating the mean of an underlying exponential distribution, and we consider both fixed sample size problems and inverse sampling schemes. Under inverse sampling, we demonstrate certain global optimality properties of an estimator based on the “total time on test” statistic. Under random sampling, it is shown than an analogous estimator is consistent, but can be improved for any fixed sample size.  相似文献   
345.
Moment estimators for the parameters of the Weibull distribution are considered in the context of analysis of field data. The data available are aggregated, with individual failure times not recorded. In this case, the complexity of the likelihood function argues against the use of maximum-likelihood estimation, particularly for relatively large sets of data, and moment estimators are a reasonable alternative. In this article, we derive the asymptotic covariance matrix of the moment estimators, and provide listings for BASIC computer programs which generate tables useful for calculation of the estimates as well as for estimating the asymptotic covariance matrix using aggregated data.  相似文献   
346.
Minimum cardinality set covering problems (MCSCP) tend to be more difficult to solve than weighted set covering problems because the cost or weight associated with each variable is the same. Since MCSCP is NP-complete, large problem instances are commonly solved using some form of a greedy heuristic. In this paper hybrid algorithms are developed and tested against two common forms of the greedy heuristic. Although all the algorithms tested have the same worst case bounds provided by Ho [7], empirical results for 60 large randomly generated problems indicate that one algorithm performed better than the others.  相似文献   
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348.
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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The Weapons Acquisition Process: An Economic Analysis By M.J. Peck and F.M. Scherer Boston: Harvard University Press, (1962).  相似文献   
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