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91.
This paper considers a combined system composed of multiple stand-by remotely piloted vehicles (RPVs) and a single battery against a single passive enemy target, where the target, if not killed, is allowed to change its location after each attack. The RPV has the duty to report on target acquisition, to confirm a target kill, and to pass information on any change in target location after each battery attack. The battery has the duty to attack the target on the basis of the target location information provided to it by the RPV. We develop a closed-form expression for the time-dependent state probabilities of the system, which can be used to compute several important combat measures of effectiveness, including (a) the time-varying mean and variance of the number of the RPVs being alive and of the surviving enemy target, (b) the mission success, mission failure, and combat draw probabilities, and (c) the mean and variance of the combat duration time. Illustrative numerical examples are solved for these combat measures, and sensitivity analyses are performed with respect to target acquisition time and target kill probability. © 1998 John Wiley & Sons, Inc. Naval Research Logistics 45: 645–667, 1998 相似文献
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针对大气层外拦截器常值姿态控制问题,设计了一种"数字变推力"姿态控制系统。通过对拦截器动力学环节合理简化,应用线性二次型最优控制理论(LQR),设计出连续型角度最优控制律,并依据廉价控制、昂贵控制等原则,选择合适的加权矩阵推导出控制量的解析表达式;根据PWPF((Pulse Width Pulse Frequency)调制原理,将用连续推力设计最优控制律用于常值推力发动机,实现了"数字变推力"姿态控制系统设计;考虑燃料消耗及PWPF线性工作区要求等应用PSO(Particle Swarm Optimization)优化算法对PWPF调制器参数进行了优化设计和仿真。仿真结果表明了该设计方法的有效性及工程应用价值。 相似文献
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针对MIL-STD-188-220C标准的路由协议多目的地址最佳转发树问题,提出一种基于遗传算法的优化算法,仿真结果表明,该算法具有收敛快,寻路成功率高的优点。 相似文献
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Yang‐Ming Chang 《Defence and Peace Economics》2013,24(3):149-169
This paper presents a simple model to characterize explicitly the role that an intervening third party plays in raising the cost of rebellion in an intrastate conflict. Extending the Gershenson‐Grossman (2000) framework of conflict in a two‐stage game to the case involving outside intervention in a three‐stage game as in Chang et al. (2007b), we examine the conditions under which an outside party optimally intervenes such that (i) the strength of the rebel group is diminished or (ii) the rebellion is deterred altogether. We also find conditions in which a third party optimally intervenes but at a level insufficient to deter rebellion. Such behavior, which improves the incumbent government’s potential to succeed in conflict, is overlooked in some conflict studies evaluating the effectiveness of intervention. One policy implication of the model is that an increase in the strength of inter‐governmental trade partnerships increases the likelihood that third‐party intervention deters rebellion. 相似文献
98.
Using the Solow–Swan growth model and the time‐trend included in the aggregate production function, this study applies the multivariate cointegration approach to re‐investigate the long‐run and causal relationships between defence expenditures and GDP while controlling for capital and labour input in Taiwan during the 1955–2002 period. It examines the long‐run causal relationship using the weak exogeneity test and utilizes general impulse response functions to determine whether a shock to defence expenditures affects economic growth or vice versa. Our findings provide substantive evidence in favour of the existence of a long‐run equilibrium cointegrated relationship between defence expenditures, GDP, labour and capital stock. The results of the weak exogeneity test indicate that a bi‐directional causal relationship exists in the long‐run between defence expenditures and GDP. Thus, the main policy implication that emerges from the long‐run results is that increasing defence expenditures in Taiwan is an effective means to boost overall economic performance and, with this improved economy, it should then be able to increase its defence expenditures further. Lastly, from our dynamic vector error correction model estimations, it is found that defence expenditures are a major means of adjusting for disequilibria that occur within the system. 相似文献
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AbstractThis study examines the causal nexus between defence spending and education expenditure in China using the bootstrap Granger full-sample causality test and sub-sample rolling window estimation. The full-sample result indicates that there is no causality between defence spending and education expenditure. By adopting a time-varying rolling window approach to revisit the dynamic causal relationships, this article identifies a negative unidirectional causality running from education expenditure to defence spending. The finding suggests that it is the education expenditure crowds out defence spending in China rather than reverse. No causality is demonstrated from defence spending to education expenditure, indicating that an increase in military spending will not crowd out expenditure on education. The results could be partly explained by that the education expenditure in China is below the requirement of corresponding economic growth, urging for more financial budget. Whereas the findings support a negative trade-off between defence and education expenditures, they refute the theory of ‘guns for butter’. 相似文献
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