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161.
不可观测系统的部分状态可观测性对于大系统故障检测具有十分重要的意义.研究了基于部分可观测性的不可观测离散线性系统测点优化配置问题,证明了采用有限次观测值构造一个矩阵,可以给出部分可观测性成立的充分必要条件,并进一步证明了部分可观测性的度量可以用一个矩阵的秩的特性来刻画.最后,给出了离散线性系统部分可观测性测试优化配置的度量指标.算例表明,提出的部分可观测性度量指标具有简单实用的特点.  相似文献   
162.
健康评估是卫星在轨安全健康工作的关键技术之一.针对卫星控制系统的健康状态评估问题,首先分析了卫星控制系统的内部结构特征,将控制系统按其结构分层并提出了基于层次推理地健康状态评估方法,然后通过分析系统特有的工作关系确定了各级系统状态数的计算方法,最后以某型气象卫星的一种控制模式为例计算了从部件到整系统的各级别状态数.计算以及仿真的结果显示该方法能够利用状态数合理地表示控制系统的健康状态.  相似文献   
163.
对任意正整数n,Pd(n)定义为n的所有正因子的乘积,gd(n)定义为n的所有小于n的正因子的乘积。若n=p1^a1p2^a2…px^as是n的标准分解式,算数函数Ω(n)=a1+a2+…+as。用解析的方法研究关于Smarandache序列Pd(n)、qd(n)与Q(n)的混合均值,并给出两个较好的渐近公式。  相似文献   
164.
HVU护航编队防空作战模型   总被引:1,自引:0,他引:1  
以M.Poulos的防空作战模型为基础,将护航编队防空分为区域防御和点防御2个层次,在进行必要的假设和简化后,建立了HVU (high value units)护航编队防空作战模型.在此模型的基础上,假设护航编队面114 3种攻击态势,对各种态势的防空效能进行了计算,得出了护航编队防空作战效能的衡量标准应选择HVU目标的剩余生命力为依据的结论,并建议为提高护航编队的防空作战效能,HVU应装备防御能力较强的点防御舰空导弹.  相似文献   
165.
刑事和解制度着眼于治疗创伤与恢复被破坏的社会关系,在寻求抚慰与宽容中伸张正义。刑事和解制度有利于被害人利益的恢复与加害人回归社会,有利于提高司法效益,有利于恢复被破坏的社会关系,从而有利于社会主义和谐社会的构建。  相似文献   
166.
Myerson 3 and 4 proposed and characterized a modification of the Shapley value in the context of communication situations. In this paper we propose several characterizations of the extension of the Banzhaf value proposed by Owen 7 to communication situations. In particular we characterize this value with the properties of fairness, isolation, and pairwise merging. © 2006 Wiley Periodicals, Inc. Naval Research Logistics, 2006  相似文献   
167.
Noise and whole-body vibration measurements were made in a Viking military vehicle to determine the variation that should be expected during repeat measures, the effect of speed (up to 60 km/h in 5 km/h increments), and during travel over different types of terrain (comprising concrete road, gravel track and rough cross-country). Measurements were made at various crew positions (including the driver and commander) in both the front and the rear cabs in the vehicles. Three translational axes of vibration were measured in each seat. Two speeds were investigated over road (35 km/h and 55–60 km/h) and gravel (20 km/h and 35 km/h) surfaces. The effect of varying speed of the vehicle on the measured noise and vibration magnitudes was also investigated. The highest sound pressure level (LAeq) of 104 dB(A) was measured at the commander’s standing position during travel over concrete road at 55 km/h. Higher noise levels occurred for a standing commander compared with when sitting on the seat. A maximum single axis frequency-weighted vibration magnitude of 1.0 m/s2 r.m.s. was measured on the driver’s seat during travel over track at 35 km/h. Higher vibration magnitudes occurred during travel over track compared with travel over road. Both noise and vibration exposure of crew within the Viking vehicle increased with increasing speed of the vehicle.  相似文献   
168.
磁通门探测器的数值分析与仿真   总被引:2,自引:1,他引:1  
给出了磁通门探测器的数学模型及其数值分析和计算机仿真的方法,并通过实例计算和模拟探测器内部各种物理量的波形、量值和相互关系,解决了电压源激励和非正弦波激励在传统分析计算中存在的难题,最后针对第Ⅱ类磁芯进行了分析.  相似文献   
169.
This study examines the relationship between defence spending, other components of public spending and economic growth for the 1952–2012 period in China using Granger causality tests and generalised impulse response functions based on vector error correction models. The empirical results reveal two long-run equilibrium relationships among the variables and also show that defence spending inversely and unidirectionally Granger impacts economic growth. Furthermore, empirical findings point to a trade-off relationship between defence spending and public expenditures in China. From a policy maker’s perspective, the findings reported herein imply that a decrease in defence spending may stimulate economic growth.  相似文献   
170.
The economic growth effects of military expenditure have been the subject of a large literature in defence economics. Theories on the economic impacts of military expenditure greatly differ and include arguments that they either enhance economic growth or crowd out productive investments. Empirical literature on defence expenditure and economic growth nexus generally employs linear specifications to investigate the impact of defence expenditures on economic growth. Although it is now well established that many economic variables may have a non-linear data-generating mechanism, it seems that this reality has long been neglected in empirical work on defence–growth nexus. This paper attempts to fill this gap by employing non-linear panel data models to examine the effects of military expenditures on economic growth for Middle Eastern countries and Turkey, for the time period 1988–2012. Results show that the effect of military expenditure on economic growth is nonlinear such that the state of the economy actually determines the effect of the former on the latter. This is important not only in showing asymmetric relationship between these variables but also in revealing the reasons of mixed results of earlier literature.  相似文献   
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