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91.
根据导弹武器战斗能力量化评估的需要,分析了导弹武器战斗能力的影响因素,运用量纲分析理论,分层次建立起了战斗能力指数评定模型,并对各子指标的量化进行了分析.以这种评价方法得到的"指数",反映问题直观、简单,适合于敌我双方实力的对比,并且与指挥员习惯相一致.  相似文献   
92.
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 Gershenson, D. and Grossman, H.I. 2000. Civil conflict: ended or never ending?. Journal of Conflict Resolution, 44(6): 807821.  [Google Scholar]) 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 Chang, Y.‐M., Potter, J. and Sanders, S. 2007b. War and peace: third‐party intervention in conflict. European Journal of Political Economy, 23(4): 954974.  [Google Scholar]), 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   
93.
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   
94.
Abstract

This 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   
95.
针对自由漂浮空间机器人在关节故障情况下关节锁定位置的辨识问题,根据其线动量守恒和角动量守恒特性,建立了关节故障锁定位置辨识的误差模型,提出了利用混沌粒子群优化(CPSO)搜索关节故障位置的辨识算法。最后采用虚拟样机技术,建立了空间机器人系统的虚拟样机,对空间机器人系统进行动力学仿真,获取了运动数据,采用此数据对提出的关节故障位置辨识算法进行了有效性验证。  相似文献   
96.
本文描述了机器人路径规划的一种新方法:基于转移费用矩阵的机器人路径规划方法。通过定义转移费用矩阵的概念及其上的二元运算,将最优路径的生成,转化为矩阵的运算,使得有限步的矩阵运算,即可得到环境中所有点间的最优路径,达到了在预处理阶段构造最优路径集的目的。最后,介绍了该方法在移动机器人任务规划中的应用  相似文献   
97.
本文利用双机械手协调内力和外力控制系统的简化模型,分析了在双手紧夹持物体与环境接触时,1) 机械手等效电机的动态特性;2) 双手所夹持物体的刚度;3) 双手所操作物体的动态特性;4) 机械手的采样控制延时;5) 双手的非对称性等系统未建模因素对双手对称式协调外力和内力控制稳定性的影响,并给出仿真结果。此结果与实验结果基本相符。  相似文献   
98.
讨论了激波灭火技术的基本原理, 给出可行的研究路线。采用新型的计算效率较高的ENO差分格式, 从非定常EULER方程出发, 对近地爆炸波产生的流场进行数值模拟, 分析后认为控制爆炸波后风场是关键。  相似文献   
99.
机器人操作空间加速度信号应用研究   总被引:1,自引:0,他引:1       下载免费PDF全文
机器人力控制存在着动力学不稳定性问题,即系统响应速度和稳定性之间的矛盾。在操作空间一级引人加速度正反馈,既能使系统的响应频带变宽,又能提高系统阻尼。这种方法能有效地提高机器人对高刚度环境的适应性,使力控制的动力学不稳定性问题得到明显地缓和;另外本文研究了用加速度积分信号代替位置差分速度信号来消除差分噪声,提高力控制精度方法的应用前景。  相似文献   
100.
讨论了快擦写存储器典型位元结构及其存储信息原理,详细论述了目前广泛使用的或非和与非两种结构的快擦写存储矩阵的结构组成和工作原理。  相似文献   
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