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101.
针对传统多属性决策投影算法不能有效评估投影值相近方案的不足之处,提出了一种基于相近方案在理想方案和负理想方案上投影值的相对贴近度改进型方法,并给出了算法的具体步骤。仿真实例表明,改进算法可有效地对投影值相近方案进行二次评估,评估结果合理。  相似文献   
102.
定义了A-紧1-集压缩映象场的广义度,扩展了1984年张庆雍建立的半紧1-集压缩映射的不动点指数理论。  相似文献   
103.
分析了单一评估方法的局限性,基于兼容度准则提出一种将综合指数法和功效评分法等常用评估方法组合而成的一种综合评估方法,采用该方法对潜艇声纳的作战性能进行了评估分析.算例分析表明,该方法对于提高评估结果的可信性具有明显的作用.  相似文献   
104.
针对小子样维修性试验因数据异总体而导致验前信息融合精度低的问题,提出了基于信息可用度的验前信息折合模型,解决了因数据异总体无法融合的问题;利用随机加权法对验前分布参数进行了拟合,准确地表述了验前分布;提出了基于支持度的融合权值确定方法,提高了各验前分布融合权值分配的合理性;最后,通过某装备维修性试验验前信息融合实例,表明了该方法具有一定的工程应用价值。  相似文献   
105.
作战指挥系统的优劣程度,通常用系统内信息传递的及时性和准确度两项指标进行衡量,结构熵理论中时效和质量两种度量方式可以有效地对这两项指标进行定量分析。运用这一理论对网络空间作战指挥系统的传统型构建方式和改进型构建方式分别建立了系统有序度模型,结合实例进行评价分析,从而论证两种作战指挥系统结构优劣程度,为网络空间作战指挥体系的构建提供参考。  相似文献   
106.
ABSTRACT

Even with sizable economic inputs, access to foreign technologies, and considerable political will, China, up until the late 1990s, experienced only limited success when it came to the local design, development, and manufacture of advanced conventional weapons. Not surprisingly, therefore, reforming the local defense industry in order to upgrade its technology base and manufacturing capabilities and to make armaments production more efficient and cost-effective has long preoccupied the Chinese leadership. The fact that most of these efforts had little positive impact on the country’s military technological and industrial capabilities only encouraged Beijing to experiment with additional reforms in the hopes of finally getting it right.  相似文献   
107.
In this article, we analyze a discrete‐time queue that is motivated from studying hospital inpatient flow management, where the customer count process captures the midnight inpatient census. The stationary distribution of the customer count has no explicit form and is difficult to compute in certain parameter regimes. Using the Stein's method framework, we identify a continuous random variable to approximate the steady‐state customer count. The continuous random variable corresponds to the stationary distribution of a diffusion process with state‐dependent diffusion coefficients. We characterize the error bounds of this approximation under a variety of system load conditions—from lightly loaded to heavily loaded. We also identify the critical role that the service rate plays in the convergence rate of the error bounds. We perform extensive numerical experiments to support the theoretical findings and to demonstrate the approximation quality. In particular, we show that our approximation performs better than those based on constant diffusion coefficients when the number of servers is small, which is relevant to decision making in a single hospital ward.  相似文献   
108.
针对现代武器装备发展趋势及维修保障要求,以Borland Delphi为平台,采用关系数据库技术,开发了新型火炮装备的IETM系统。该系统将各种格式图像信息统一整合,采用Cult3D技术实现三维模型的人机交互,提供了方便快捷的检索方式。  相似文献   
109.
《防务技术》2022,18(11):1979-1999
A quasi-isentropic study on the process of driving a cylinder with aluminized explosives was carried out to examine the influence of the aluminum (Al) reaction rate on cylinder expansion and the physical parameters of the detonation products. Based on the proposed quasi-isentropic hypothesis and relevant isentropic theories, the characteristic lines of aluminized explosives driving a cylinder were analyzed, and a quasi-isentropic model was established. This model includes the variation of the cylinder wall velocity and the physical parameters of the detonation products with the Al reaction degree. Using previously reported experimental results, the quasi-isentropic model was verified to be applicative and accurate. This model was used to calculate the physical parameters for cylinder experiments with aluminized cyclotrimethylenetrinitramine explosives with 15.0 % and 30.0 % Al content. The results show that this quasi-isentropic model can be used not only to calculate the cylinder expansion rule or Al reaction degree, but also to calculate the physical parameters of the detonation products in the process of cylinder expansion. For explosives with 15.0 % and 30.0 % Al, 24.3 % and 18.5 % of the Al was found to have reacted at 33.9 μs and 34.0 μs, respectively. The difference in Al content results in different reaction intensity, occurrence time, and duration of two forms of reaction (diffusion and kinetic) between the Al powder and the detonation products; the post-detonation burning reaction between the Al powder and the detonation products prolongs the positive pressure action time, resulting in a continuous rise in temperature after detonation.  相似文献   
110.
The explosive reaction degree and protection from explosions are concerns in the military field.In this work,the reaction degree of the composition B explosive was investigated experimentally.Multi-layered compound structures were used as barriers to weaken the blast loads.A comprehensive experiment using a high-speed camera and image processing techniques,side witness plates,and bottom witness plates was presented.Using the experimental fragment velocities,fragment piercing patterns,and damage characteristics,the reaction degree of the explosive impeded by different multi-layered com-pound structures could be precisely differentiated.Reaction parameters of the explosive obstructed by compound structures were obtained by theoretical analysis and numerical simulations.Unlike the common method in which the explosive reaction degree is only distinguished based on the initial pressure amplitude transmitted into the explosive,a following shock wave reflected from the side steel casing was also considered.Different detonation growth paths in the explosive formed.Therefore,all these shock wave propagation characteristics must be considered to analyze the explosive response impeded by compound structures.  相似文献   
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