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481.
We undertake inference for a stochastic form of the Lanchester combat model. In particular, given battle data, we assess the type of battle that occurred and whether or not it makes any difference to the number of casualties if an army is attacking or defending. Our approach is Bayesian and we use modern computational techniques to fit the model. We illustrate our method using data from the Ardennes campaign. We compare our results with previous analyses of these data by Bracken and Fricker. Our conclusions are somewhat different to those of Bracken. Where he suggests that a linear law is appropriate, we show that the logarithmic or linear‐logarithmic laws fit better. We note however that the basic Lanchester modeling assumptions do not hold for the Ardennes data. Using Fricker's modified data, we show that although his “super‐logarithmic” law fits best, the linear, linear‐logarithmic, and logarithmic laws cannot be ruled out. We suggest that Bayesian methods can be used to make inference for battles in progress. We point out a number of advantages: Prior information from experts or previous battles can be incorporated; predictions of future casualties are easily made; more complex models can be analysed using stochastic simulation techniques. © 2000 John Wiley & Sons, Inc. Naval Research Logistics 47: 541–558, 2000  相似文献   
482.
When solving location problems in practice it is quite common to aggregate demand points into centroids. Solving a location problem with aggregated demand data is computationally easier, but the aggregation process introduces error. We develop theory and algorithms for certain types of centroid aggregations for rectilinear 1‐median problems. The objective is to construct an aggregation that minimizes the maximum aggregation error. We focus on row‐column aggregations, and make use of aggregation results for 1‐median problems on the line to do aggregation for 1‐median problems in the plane. The aggregations developed for the 1‐median problem are then used to construct approximate n‐median problems. We test the theory computationally on n‐median problems (n ≥ 1) using both randomly generated, as well as real, data. Every error measure we consider can be well approximated by some power function in the number of aggregate demand points. Each such function exhibits decreasing returns to scale. © 2003 Wiley Periodicals, Inc. Naval Research Logistics 50: 614–637, 2003.  相似文献   
483.
484.
China’s rapid economic growth is facilitating massive increases in its military spending and causing increased security concerns in Asia and the Western Pacific. But there is uncertainty over how large China’s military spending is relative to other countries, or how fast it is growing in real terms. We address this issue by deriving a relative military cost price index based on the relative unit costs of inputs. We find that China’s real military spending is much larger than suggested by exchange rate comparisons, and even larger than standard purchasing power parity comparisons. We also find, however, that the real growth of China’s military spending has been smaller than conventionally thought. This is due to rapidly growing wages in China and the large share of personnel in China’s military budget.  相似文献   
485.
Many contributors to military ethics from diverse locations and philosophical perspectives maintain that virtues are central to martial theory and practice. Yet several contemporary philosophers and psychologists have recently challenged the empirical adequacy of this perspective. Their challenge is known as the situationist critique, a version of which asserts that: (a) situational features rather than character traits such as virtues cause and explain human behavior, and (b) ethical theories and development programs are empirically inadequate to the extent that they incorporate virtues. In this paper, I assess the merit of this critique and consider some implications of my assessment for military practitioners and theorists.  相似文献   
486.
An institutional perspective on nuclear deterrence cooperation within alliances has the potential to fundamentally reorient how we think about analyzing nuclear and deterrence decision-making between nuclear patrons and non-nuclear clients. It comes at a time when the presidency of Donald Trump is sure to test many of the core claims and assumptions in security studies, especially relating to bargaining and credibility within alliances. This article surveys questions that will be core to the research agenda involving alliance institutions and nuclear weapons during the Trump presidency and beyond.  相似文献   
487.
To manage their assets at an enterprise level, defense organizations have turned to portfolio theory for the planning, analysis and management of their military forces and materiel. Despite being well established in the commercial sector, the application of portfolio approaches in defense is problematic. The vexatious question for defense of how to define and measure benefits arising is complicated by the increased utility and effectiveness achieved through networking of military forces and the equipment they use. The authors discuss the challenges for defense in using a portfolio approach and propose a conceptual model for dealing with the effects arising from networking with information and communications technologies.  相似文献   
488.
International technical cooperation on issues relevant to the challenges of nuclear disarmament can demonstrate commitment to obligations under Article VI of the Treaty on the Non-Proliferation of Nuclear Weapons, strengthen the security of fissile materials and weapons, and develop technical approaches to support more ambitious disarmament activities in the future. Including non-nuclear weapon states would ensure that their views are taken into account and would invest them in developing solutions to key challenges. This article discusses three areas for technical cooperation that would build on past activities and that could produce such benefits as improved protection, control, and accounting of nuclear weapons and fissile material; enhanced transparency for nuclear weapon complexes; and mechanisms for international management of sensitive civilian nuclear facilities. International cooperation in each of these areas could provide a technical basis for pursuing possible future disarmament negotiations and substantively demonstrate commitment to Article VI.  相似文献   
489.
在系统奇点唯一的条件下,研究了一类微分系统不存在极限环的的充分条件,运用和发展了以往的结果.  相似文献   
490.
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