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11.
With the words quoted above, the new Secretary of State for Defence in the Thatcher government revealed for the first time the existence of a project that have remained a closely guarded secret, even from amny Cabinet members of four governments, since the late 1960s. Despite the passage of more thatn 20 years since Mr Pym's announcement, the story of the Chevaline project still remains largely unknown outside a small group of select politicians, officials and scientists. This article sets out to use recently declassified documents and what is in the public domain to tell the story of Chevaline from the secret debates about the need to improve Britain's Polaris deterrent force shortly after it was deployed in the late 1960s to the official announcement of the project in 1980 and its eventual operational deployment in 1982. In particular, attention is focused on three main questions: Why was the project kept secret for so long? Why did the improvement programme take so long to come to fruition? Why, given the spiralling costs involved, was it not cancelled? In order to consider these questions relating to what Pym described as ‘the front end’ of the Poaris missile, it is necessary to begin by looking at the background to the project.  相似文献   
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Book reviews     
John Lawrence Tone, The Fatal Knot: The Guerrilla War in Navarre and the Defeat of Napoleon in Spain. Chapel Hill and London; The University of North Carolina Press 1994. Pp.vii + 239, 1 map, biblio., index. $34.95 (cloth). ISBN 0–8078–2169–1.

Robert Holland (ed), Emergencies and Disorder in the European Empires after 1945. London: Frank Cass, 1994. Pp.x + 256; index. £32 (cloth); £15 (paper). ISBN 0–7146–4516–8 and 4109 X

Deborah L. Norden, Military Rebellion in Argentina: Between Coups and Consolidation. Lincoln, NE: University of Nebraska Press, 1996. Pp.242, index, $35/$17.50 (paper). ISBN 0–8032–8369–5.

William M. Minter, Apartheid's Contras: An Inquiry into the Roots of War in Angola and Mozambique. London and Atlantic Highlands, NJ: Zed Books Ltd; Johannesburg: Witwatersrand University Press, 1994. Pp. xii +308, 3 maps, biblio., index. $69.95/£39.95 (cloth); $29.95/£16.95(paper). ISBN 1–85649–266–4 and 266–4.  相似文献   
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Models are formulated for determining continuous review (Q, r) policies for a multiitem inventory subject to constraints. The objective function is the minimization of total time-weighted shortages. The constraints apply to inventory investment and reorder workload. The formulations are thus independent of the normal ordering, holding, and shortage costs. Two models are presented, each representing a convex programming problem. Lagrangian techniques are employed with the first, simplified model in which only the reorder points are optimized. In the second model both the reorder points and the reorder quantities are optimized utilizing penalty function methods. An example problem is solved for each model. The final section deals with the implementation of these models in very large inventory systems.  相似文献   
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An allocation problem is considered in lvhich different kinds of resources must be allocated to various activities, within a given time period. The opportunities for allo'cation appear randomly during this period. Certain assumptions about the values of possible allocations and the distribution of occurrences of opportunities lead to a dynamic programming formulation of the problem. This leads to a system of ordinary differential equations which are (in theory) solvable recursively, and can be solved numerically to any desired degree of precision. An example is given for the allocation of aircraft-carried weapons to targets of opportunity.  相似文献   
17.
Book Reviews     
Men, Ideas and Tanks: British Military Thought and Armoured Forces, 1903–1939. By J. P. Harris, Manchester University Press, (1995) ISBN 0 7190 3762 (hardback) £40.00 or ISBN 0 7190 4814 (paperback) £14.99

Fighting for Ireland. By M. L. R. Smith. London and New York: Routledge, (1995) ISBN 0–415–09161–6.

The Fundamentals of British Maritime Doctrine (BR1806) HMSO London (1995) ISBN 0–11–772470‐X £9.50

Regional Conflicts: The Challenges to US‐Russian Co‐Operation Edited by James E. Goodby SIPRI: Oxford University Press 1995 ISBN 019‐S29–171X, £30.00

SIPRI Yearbook 1995 ‐ Armaments, Disarmament and International Security Oxford: Oxford University Press 1995. ISBN 019–829–1930, £60.00.

Drug Trafficking in the Americas Edited by Bruce M. Bagley & William O. Walker III Transaction Publishers, New Brunswick, (USA), 1994 ISBN 1–56000–752–4.

Raglan: From the Peninsula to the Crimea By John Sweetman, Arms & Armour 1993. ISBN 1–85409–059–3. £19.00.  相似文献   

18.
We consider sequencing n jobs on a single machine subject to job completion times arising from either machine breakdowns or other causes. The objective is to minimize an expected weighted combination of due dates, completion times, earliness, and tardiness penalties. The determination of optimal distinct due dates or optimal common due dates for a given schedule is investigated. The scheduling problem for a fixed common due date is considered when random completion times arise from machine breakdowns. The optimality of a V-shaped about (a point) T sequence is established when the number of machine breakdowns follows either a Poisson or a geometric distribution and the duration of a breakdown has an exponential distribution. © 1996 John Wiley & Sons, Inc.  相似文献   
19.
A posynomial geometric programming problem formulated so that the number of objective function terms is equal to the number of primal variables will have a zero degree of difficulty when augmented by multiplying each constraint term by a slack variable and including a surrogate constraint composed of the product of the slack variables, each raised to an undetermined negative exponent or surrogate multiplier. It is assumed that the original problem is canonical. The exponents in the constraint on the product of the slack variables must be estimated so that the associated solution to the augmented problem, obtained immediately, also solves the original problem. An iterative search procedure for finding the required exponents, thus solving the original problem, is described. The search procedure has proven quite efficient, often requiring only two or three iterations per degree of difficulty of the original problem. At each iteration the well-known procedure for solving a geometric programming problem with a zero degree of difficulty is used and so computations are simple. The solution generated at each iteration is optimal for a problem which differs from the original problem only in the values of some of the constraint coefficients, so intermediate solutions provide useful information.  相似文献   
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