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With repeated firing, fatigue cracks are produced in a gun barrel, and the barrel is no longer useful when a crack reaches a critical size. The initial crack size and the critical crack size, as well as the number of firings producing the critical crack size, may be considered as random variables. Assuming a proportional damage model for crack growth, a method for estimating the critical crack size distribution is presented. From these results, an estimate of the barrel life, or the residual barrel life once a crack of a given size is measured, can be obtained. 相似文献
483.
In this article we present a proportional hazards model for describing machine tool failures. The model enables us to describe the effect of aging as well as the effect of the machining environment on tool life. We discuss inference for the model and show that computable results can be obtained in a fully Bayesian analysis by using approximation techniques. We illustrate the usefulness of our model by applying it to some actual data on machine tool failures. 相似文献
484.
This article investigates the little-known plans formulated by Harold Wilson's Labour government to deploy Polaris submarines in the Indo-Pacific region. The scheme was first proposed in 1965 as a response to several problems faced by British policy-makers, including China's acquisition of a nuclear capability, Britain's wish to maintain a meaningful position ‘East of Suez’ at reduced cost, and German pressure for equal treatment within NATO on nuclear matters. Despite extensive high-level discussion, the plans were finally abandoned in mid-1968, as Labour moved more decisively to forsake the world role. 相似文献
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Matthew Hughes W. J. R. Gardner Ian F. W. Beckett Eric Grove Philip Jones Craig A. Snyder 《战略研究杂志》2013,36(4):160-169
John Horsfield, The Art of Leadership in War. The Royal Navy From the Age of Nelson to the End of World War II. Westport, Conn. and London: Greenwood Press, 1980. Pp. 240; £14.75. John Joseph Timothy Sweet, Iron Arm: The Mechanization of Mussolini's Army, 1920–1940. Westport, Connecticut &; London: Greenwood Press. 1980. Pp. 207; £15.50. Peter H. Merkl, The Making of a Stormtrooper. Princeton, N.J: Princeton U.P., 1980. Pp. 328; £8.60. Greg Herken, The Winning Weapon: The Atomic Bomb in the Cold War 1945–1950. New York: Alfred A. Knopf, 1980. Pp. 425; $15.00. Geoffrey Smith and Nelson W. Polsby, British Government and its Discontents. New York: Basic Books, and London: Harper and Row, 1981. Pp. 202; £7.95. Seweryn Bialer (ed.), The Domestic Context of Soviet Foreign Policy. Boulder, Colorado: Westview Press and London: Croom Helm, 1981. Pp. 441; £14.95. Jerry F. Hough, Soviet Leadership in Transition. Washington, D.C.: Brookings Institution and Oxford, Basil Blackwell, 1981. Pp. 175; £12.00 (hb.) and £3.95 (pb.) Edward F. Mickolus, Transnational Terrorism: A Chronology of Events 1968–1979. London: Aldwych Press, 1980. Pp. 967; £39.95. Barry Rubin, The Great Powers in the Middle East, 1941–47; The Road to the Cold War, London: Frank Cass, 1980. Pp. 254; £14.50; Daniel Heradstveit, The Arab‐Israeli Conflict; Psychological Obstacles to Peace. Oslo: Universittsforlaget, 1979. Pp. 234; £11.60; Janice Gross Stein, and Raymond Tanter, Rational Decision‐making; Israel's Security Choices 1967. Columbus. Ohio; Ohio State University Press, 1980. Pp. 399; $35. 相似文献
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Washington's so-called Maritime Strategy, which sought to apply US naval might against Soviet vulnerabilities on its maritime flanks, came to full fruition during the 1980s. The strategy, which witnessed a major buildup of US naval forces and aggressive exercising in seas proximate to the USSR, also explicitly targeted Moscow”s strategic missile submarines with the aim of pressuring the Kremlin during crises or the early phases of global war. Relying on a variety of interviews and newly declassified documents, the authors assert that the Maritime Strategy represents one of the rare instances in history when intelligence helped lead a nation to completely revise its concept of military operations. 相似文献
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