首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   2175篇
  免费   4篇
  国内免费   6篇
航空   756篇
航天技术   764篇
综合类   8篇
航天   657篇
  2022年   6篇
  2021年   22篇
  2019年   7篇
  2018年   73篇
  2017年   58篇
  2016年   56篇
  2015年   20篇
  2014年   69篇
  2013年   68篇
  2012年   66篇
  2011年   109篇
  2010年   81篇
  2009年   128篇
  2008年   144篇
  2007年   81篇
  2006年   51篇
  2005年   66篇
  2004年   71篇
  2003年   83篇
  2002年   53篇
  2001年   90篇
  2000年   38篇
  1999年   41篇
  1998年   43篇
  1997年   35篇
  1996年   49篇
  1995年   40篇
  1994年   33篇
  1993年   20篇
  1992年   35篇
  1991年   9篇
  1990年   12篇
  1989年   34篇
  1988年   13篇
  1987年   18篇
  1986年   20篇
  1985年   67篇
  1984年   35篇
  1983年   25篇
  1982年   37篇
  1981年   66篇
  1980年   16篇
  1979年   6篇
  1978年   7篇
  1977年   13篇
  1976年   9篇
  1975年   14篇
  1974年   15篇
  1973年   8篇
  1970年   4篇
排序方式: 共有2185条查询结果,搜索用时 15 毫秒
101.
102.
Based on an integrated approach, we solve the optimization problem for energy content and weight-dimensional characteristics of the electric servo drive by synthesis of structure and analysis of characteristics for different power supplies. The generalized power supply model, developed for different power supply of drive control systems, is given.  相似文献   
103.
We consider the stability of stationary motions of a model of a spacecraft as a system of coaxial bodies with small asymmetry caused by the shift of the axes of dynamic symmetry of bodies relative to the axis of rotation. We determine the stationary motions of the system; their stability is studied with respect to both the projections of angular velocity and the position of the axis of rotation. The sufficient conditions for the stability of these stationary motions are obtained by constructing a Lyapunov function, and the necessary conditions are obtained by analyzing the corresponding linearized equations of perturbed motion.  相似文献   
104.
This paper presents the results of analyzing the shaping of thin-walled conical parts with the uniform thickness along generatrix.  相似文献   
105.
The discretization of the boundary value problem for laminated composite shells is based on the finite difference approach using the regular mesh with the constant grid step and the difference operators of the second order of accuracy. The dynamic relaxation method is proposed for the solution of the nonlinear problem. The evolutionary equations of the dynamic relaxation are constructed, and the optimum parameters of the converging linear iterative process are estimated.  相似文献   
106.
We consider the peculiarities of application for the cabin indicating systems of secondary information display, formulate and systematize the compositional and technical requirements for display systems and their elements. The tendencies and lines in the development of head-up displays for avionics and autobasing complexes were determined. The technique of calculating optics of such display systems with the use of electronic distortion compensation is presented.  相似文献   
107.
A concept of monitoring for material properties with residual life estimation of rotor blades for gas turbine engines is proposed. The structure of on-board control and conditionmonitoring system based on the intelligent pyrometer module with the algorithm for calculating the residual life of turbine rotor blades is described.  相似文献   
108.
This paper considers a beam with a technological longitudinal section on the level of the gravity center of the cross section that is loaded by a vertical concentrated force. We study the structure durability depending on the load amplitude and the initial crack length.  相似文献   
109.
The results of designing the attitude control system of the first Russian nanosatellite TNS-0 no. 1 providing orientation of its longitudinal axis along the local geomagnetic field induction vector are presented. The system consists of a permanent magnet and two sets of hysteresis rods. The magnetic and geometric parameters of the magnet and rods are calculated. The influence of the permanent magnet field on the hysteresis rods and mutual influence of the rods in the case of compact satellite packaging are analyzed. Examples of calculations of transient processes and steady-state angular satellite motion are presented.  相似文献   
110.
The paper discusses a method of designing the neural controller for two-channel control of a technical object by an example of the roll and yaw control depending on deviations, velocities and accelerations of their variation.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号