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251.
Testing provides essential information for managing infectious disease outbreaks, such as the COVID-19 pandemic. When testing resources are scarce, an important managerial decision is who to test. This decision is compounded by the fact that potential testing subjects are heterogeneous in multiple dimensions that are important to consider, including their likelihood of being disease-positive, and how much potential harm would be averted through testing and the subsequent interventions. To increase testing coverage, pooled testing can be utilized, but this comes at a cost of increased false-negatives when the test is imperfect. Then, the decision problem is to partition the heterogeneous testing population into three mutually exclusive sets: those to be individually tested, those to be pool tested, and those not to be tested. Additionally, the subjects to be pool tested must be further partitioned into testing pools, potentially containing different numbers of subjects. The objectives include the minimization of harm (through detection and mitigation) or maximization of testing coverage. We develop data-driven optimization models and algorithms to design pooled testing strategies, and show, via a COVID-19 contact tracing case study, that the proposed testing strategies can substantially outperform the current practice used for COVID-19 contact tracing (individually testing those contacts with symptoms). Our results demonstrate the substantial benefits of optimizing the testing design, while considering the multiple dimensions of population heterogeneity and the limited testing capacity. 相似文献
252.
A well‐studied problem in airline revenue management is the optimal allocation of seat inventory among different fare‐classes, given a capacity for the flight and a demand distribution for each class. In practice, capacity on a flight does not have to be fixed; airlines can exercise some flexibility on the supply side by swapping aircraft of different capacities between flights as partial booking information is gathered. This provides the airline with the capability to more effectively match their supply and demand. In this paper, we study the seat inventory control problem considering the aircraft swapping option. For theoretical and practical purposes, we restrict our attention to the class of booking limit policies. Our analytical results demonstrate that booking limits considering the swapping option can be considerably different from those under fixed capacity. We also show that principles on the relationship between the optimal booking limits and demand characteristics (size and risk) developed for the fixed‐capacity problem no longer hold when swapping is an option. We develop new principles and insights on how demand characteristics affect the optimal booking limits under the swapping possibility. We also develop an easy to implement heuristic for determining the booking limits under the swapping option and show, through a numerical study, that the heuristic generates revenues close to those under the optimal booking limits. © 2011 Wiley Periodicals, Inc. Naval Research Logistics, 2011 相似文献
253.
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
254.
This article argues that an increasingly sea-power-minded China will neither shelter passively in coastal waters, nor throw itself into competition with the United States in the Pacific Ocean. Rather, Beijing will direct its energies toward South and Southeast Asia, where supplies of oil, natural gas, and other commodities critical to China's economic development must pass. There China will encounter an equally sea-power-minded India that enjoys marked geostrategic advantages. Beijing will likely content itself with ‘soft power’ diplomacy in these regions until it can settle the dispute with Taiwan, freeing up resources for maritime endeavors farther from China's coasts. 相似文献
255.
K.‐J. Müller 《战略研究杂志》2013,36(2):123-152
256.
257.
258.
Gülay Günlük-Senesen 《Defence and Peace Economics》2013,24(5):385-403
This paper investigates the budgetary trade-off structure of security (defence+internal security) expenditures in Turkey for the period 1983-1998. A modified version of Todaro's distributive share index of social welfare is used to quantify the impacts on the growth of primary budget expenditures of Security, Education, Health, General Administration, Infrastructure, and Social Services. We find that defence expenditures dominate overall security expenditures and are less affected in times of bottlenecks in the economy. A systematic pattern of negative budgetary trade-offs of security expenditures in terms of other components is not identified. We also analyse the expenditures of the Defence Industry Support Fund in an attempt to find the cost of the modernisation program to the economy. 相似文献
259.
Clive R. Pickard QGM 《Defence and Peace Economics》2013,24(4):321-330
A UK House of Commons Defence Committee (HCDC) Report on the Gulf War recommended that the UK should be self‐sufficient in supporting its Armed Forces in times of crisis and not even rely on its Allies. This recommendation is at odds with UK Government policy which rejects any formal strategy of support for the defence industrial base preferring international open competition as its procurement philosophy. This paper examines the various factors ranging from the supply of raw materials, production capacity, stockpiling, international joint ventures, and competition through to the effects on the technological update of weapon systems resulting from this philosophy. It draws conclusions supporting the HCDC recommendation and calls for joint MOD‐Industry action to address the issues involved and thereby reduce the risks to the Defence of the Realm. 相似文献
260.
Tilman Brück 《Defence and Peace Economics》2013,24(5):375-389
This paper analyses public policy choices in the security economy from an economic perspective. It discusses the role of public goods for national and global security and identifies the importance of the first‐ and second‐order indirect effects of insecurity on economic activity, which include the behavioural responses of agents and the government to security measures, akin to such effects in insurance economics. Furthermore, key public policy trade‐offs are outlined, in particular between security and efficiency, globalisation, equity and freedom. The analysis identifies suitable policy options for raising security in the national and international contexts and in view of these trade‐offs. A balance between market and non‐market instruments in achieving security should be aimed for in order to minimise the adverse effects of aiming for higher security. In addition, the public good nature of security implies that international coordination of security policies is important, despite this process being fraught with enforcement problems. 相似文献