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221.
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   
222.
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   
223.
Book reviews     
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   
224.
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   
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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   
228.
A plethora of arguments from the ‘public choice school’ suggest that public goods are ‘under‐supplied’ by comparison with public sector provision of more private goods. The implication is that rent seeking by the ‘military‐industrial complex’ serves, in some measure, to offset potential allocative inefficiency. In this paper a comparison of rent seeking by producers of public goods and producers of private goods identifies a bias that favours public good supply. The bias results from the different way in which collective demand for public goods and for private goods is expressed. The prospect of larger rents to the ‘military‐industrial complex’ implies greater rent‐seeking expenditures in this sector. The extent to which public goods (and, in particular, defence) are ‘under supplied’ is much exaggerated.  相似文献   
229.
Becoming a nuclear weapon state and sustaining a militarily credible nuclear weapons capability is far from trivial, especially for medium powers. Such a capability is demonstrated by much more than firing a first test or acquiring significant quantities of fissile material; capability is indicated by factors including weaponization, delivery of weapons, reliability and effectiveness of weapons and their delivery systems, fissile material availability, and nuclear and non-nuclear testing. Files in the British National Archives shed considerable light on the problems faced by the nuclear weapon program of the United Kingdom from 1952 through the late 1960s. The question is whether this experience is unique or if it instead offers insights into the potential problems faced by, or facing, other medium or aspiring nuclear weapon states. The proliferation-related topics highlighted include: fissile material production, nuclear testing, the first weapon, weapon delivery rates, non-nuclear testing, delivery platform problems, and long-term maintenance and capability sustainability. Further research could provide clearer insights.  相似文献   
230.
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   
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