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91.
一种用于导弹姿态控制系统的直接力非线性控制法   总被引:1,自引:0,他引:1  
奚勇  张巍巍 《上海航天》2007,24(3):42-45
为改善传统导弹姿控系统线性控制法的不足,用相平面法分析了直接力作用下导弹的姿态运动规律和气动力作用对直接力控制的影响,提出了一种综合控制精度、姿控发动机产品特性和推进剂消耗量等指标的直接力非线性控制方法,给出了控制模型。仿真结果表明,该法能在气动力作用或干扰无法忽略的条件下实现导弹姿控发动机的开关工作正常,保证精度及推进剂消耗最省,其控制精度与线性比例微分(PD)控制律相当。  相似文献   
92.
石莹  段广仁  孙德波 《宇航学报》2004,25(6):686-689
提出了视觉导航信息估计的Matlab Symbolic Computation方法,计算了视觉导航系统中6个自由度变量的最优估计的误差协方差阵的秩、特征值和特征向量,并得到了导航信息可估的条件及结论。通过仿真不仅进一步验证了文献[2]中理论推导及结论的正确性,而且简化了理论分析过程。本文提出的方法具有实际应用价值。  相似文献   
93.
基于单神经元的飞航导弹智能PID控制   总被引:1,自引:1,他引:1  
针对飞航导弹扇面发射和大空域机动飞行引起的非线性时变、建模误差等问题,根据智能控制、神经网络及传统的PID控制理论设计了一种基于单神经元的智能自整定PID控制器。仿真结果表明,该控制器可使飞航导弹的自动驾驶仪具有较好的飞行品质和精度、更强的鲁棒性,同时也能满足实时性要求,且工程实现简单。  相似文献   
94.
天线罩外形形线对天线罩性能的影响   总被引:1,自引:0,他引:1  
比较和分析了不同天线平外形形线在不同长细比情况下对天线罩的电气性能和气动特性的影响。分析认为,在设计天线罩时,应根据导弹和天线罩的综合性能要求进行综合处理。  相似文献   
95.
A modern transonic computational fluid dynamics test case is described in this paper, which is the Aerodynamic Validation Model (AVM) from the Chinese Aeronautical Establishment (CAE). The CAE-AVM is a representation of a modern transonic business jet aircraft with a design Mach number of 0.85. Numerical simulations for the AVM are conducted for two geometries: one baseline geometry, and one geometry that includes the applied model support system of the wind tunnel as well as the deformed wing shape that occurred during wind tunnel testing. The combined influence of wing deformation and model support interference on local and integral aerodynamic features is presented. Comparisons between CFD and experimental results are made; reasons of discrepancy between results from considered cases are analyzed.  相似文献   
96.
This work deals with the aerodynamic database development of the Intermediate Experiment Vehicle.  相似文献   
97.
Recent research proves that wings with leading-edge tubercles have the ability to perform efficiently in post-stall region over the conventional straight wing. Moreover, the conventional straight wing outperforms the tubercled wing at a pre-stall region which is quintessential. Even though tubercled wing offers great performance enhancement, because of the complexity of the flow, the trough region of the tubercled wing is more prone to flow separation. Henceforth, the present paper aims at surface blowing – an active flow control technique over the tubercled wing to enhance the aerodynamic efficiency by positively influencing its lift characteristics without causing any additional drag penalty. Flow parameters like blowing velocity ratios and the location of blowing were chosen to find the optimised configuration keeping the amplitude and frequency of the leading-edge tubercles constant as 0.12 c and 0.25 c respectively. Numerical investigations were carried out over the baseline tubercled wing and tubercled wing with surface blowing at various blowing jet velocity ratios 0.5, 1 and 2 over four different chordwise locations ranging from 0.3 c to 0.8 c.The results confirm that blowing at various x/c with different blowing velocity ratios performs better than the conventional tubercled wing. Comparatively, blowing velocity ratio 2 at 0.3 c shows peak performance of about 28% enhancement in the lift characteristics relative to the baseline model. Particularly, in the pre-stall region, 25–50% increase in aerodynamic efficiency is evident over the tubercled wing with surface blowing compared with the baseline case. Additionally,attempts were made to delineate the physical significance of the flow separation mechanism due to blowing by visualizing the streamline pattern.  相似文献   
98.
Based on improved multi-objective particle swarm optimization (MOPSO) algorithm with principal component analysis (PCA) methodology,an efficient high-dimension multiobjective optimization method is proposed,which,as the purpose of this paper,aims to improve the convergence of Pareto front in multi-objective optimization design.The mathematical efficiency,the physical reasonableness and the reliability in dealing with redundant objectives of PCA are verified by typical DTLZ5 test function and multi-objective correlation analysis of supercritical airfoil,and the proposed method is integrated into aircraft multi-disciplinary design (AMDEsign) platform,which contains aerodynamics,stealth and structure weight analysis and optimization module.Then the proposed method is used for the multi-point integrated aerodynamic optimization of a wide-body passenger aircraft,in which the redundant objectives identified by PCA are transformed to optimization constraints,and several design methods are compared.The design results illustrate that the strategy used in this paper is sufficient and multi-point design requirements of the passenger aircraft are reached.The visualization level of non-dominant Pareto set is improved by effectively reducing the dimension without losing the primary feature of the problem.  相似文献   
99.
以凌阳16位单片机SPCE061A为控制核心,通过所需运动轨迹曲线的参数方程建立运动控制模型,按照算法对两组驱动步进电机进行控制,实现了悬挂画笔在给定的范围内的定点运动、任意曲线运动以及圆心可任意设定的圆周运动等功能,不仅完成了要求发挥的部分功能,同时还增加了语音播放功能。  相似文献   
100.
基于气/固耦合非定常流动的叶栅颤振分析   总被引:3,自引:1,他引:3       下载免费PDF全文
杨青真  肖军  周新海 《推进技术》2005,26(6):526-530
采用二维N-S方程/结构振动方程组耦合数值方法,分析计算了二维非定常气动力强迫振动条件下振动能量及气动力对叶栅所做的功,分别根据振动能量和气动力做功分析了叶栅的颤振特性。NACA0012和PROF叶栅在不同折合频率下气动参数随时间的变化表明,折合频率是影响叶栅颤振的重要因素。气固耦合方法得到的NA-CA0012叶栅颤振折合频率比非耦合的结果高,而对PROF叶栅则相反。这表明叶栅结构动力参数对其发生颤振时的折合频率影响很大且很复杂,要准确预测颤振应该考虑叶栅结构动力与气动力的耦合因素。  相似文献   
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