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151.
介绍空间对接技术和Stewart运动平台的概念,说明目前研究空间对接仿真技术对我国具有重大意义,探讨国内外空间对接系统运动学动力学建模、半物理仿真和路径规划的研究现状,更进一步深入分析了对接综合实验台stewart平台的轨迹规划研究策略和途径. 相似文献
152.
基于嵌入式运动控制器系统的设计与开发 总被引:2,自引:4,他引:2
本文综合运用嵌入式系统技术和运动控制技术,采用X86架构的PC104作为核心中央处理器的方案,详细介绍了嵌入式运动控制器的硬件设计,及如何使用WindowsCEPlatformBuilder开发平台,进行裁减和定制嵌入式运动控制器的Win-dowsCE操作系统平台,进行软件设计。 相似文献
153.
基于运动轨迹聚类的运动分割 总被引:1,自引:0,他引:1
文中提出了一种基于子空间聚类的运动分割算法。针对基于因式分解的运动分割方法对噪声敏感的问题,引入一个基于形状相关矩阵的相似矩阵,然后将特征点映射到一个由相似矩阵决定的低维子空间中。在这个子空间中,可以通过光谱图聚类方法对特征点进行聚类。为提高光谱图聚类方法的分段常数特征向量条件,文中计算了一个相关的概率矩阵的较大特征值相对于边权重变化的敏感度,来切断类之间的连接。通过实验,可以看到文中的方法有较好的鲁棒性。 相似文献
154.
超分辨率重构技术需要考虑的几个因素 总被引:2,自引:0,他引:2
超分辨率重构指的是用低分辨率的视频重构高分辨率的视频和图像,以获得更好的视觉效果。该文分别从成像过程和压缩过程两个方面讨论了超分辨率重构过程需要考虑的因素,同时指出了运动估计和运动补偿在超分辨率重构中的重要性。文章还分析了运动估计在超分辨率重构技术中所面临的新的难题。最后,对于超分辨率算法的具体实现进行了探讨性的研究。 相似文献
155.
Calibrated,Registered Images of an Extended Urban Area 总被引:1,自引:0,他引:1
Teller Seth Antone Matthew Bodnar Zachary Bosse Michael Coorg Satyan Jethwa Manish Master Neel 《International Journal of Computer Vision》2003,53(1):93-107
We describe a dataset of several thousand calibrated, time-stamped, geo-referenced, high dynamic range color images, acquired under uncontrolled, variable illumination conditions in an outdoor region spanning several hundred meters. The image data is grouped into several regions which have little mutual inter-visibility. For each group, the calibration data is globally consistent on average to roughly five centimeters and 0 1°, or about four pixels of epipolar registration. All image, feature and calibration data is available for interactive inspection and downloading at http://city.lcs.mit.edu/data.Calibrated imagery is of fundamental interest in a variety of applications. We have made this data available in the belief that researchers in computer graphics, computer vision, photogrammetry and digital cartography will find it of value as a test set for their own image registration algorithms, as a calibrated image set for applications such as image-based rendering, metric 3D reconstruction, and appearance recovery, and as input for existing GIS applications. 相似文献
156.
Margarita Mediavilla Juan-Carlos Fraile Ignacio J. Galindo M. Teresa González 《Journal of Intelligent and Robotic Systems》2003,38(1):85-104
Strategy-based path planning was introduced by the authors as a way to give robotic manipulators some sort of reactive behaviour in dynamic and unpredictable environments. This approach is based on making robots react to moving obstacles using a restricted subset of the configuration space, and on using an off-line pre-planning stage to choose the restricted subset. In this paper, strategy-based path planning is applied and explored, focusing our attention on the off-line stage. It is applied to the joint motion of two and three robots that perform pick and place tasks sharing common working areas. 相似文献
157.
Reusing Primitive and Acquired Motion Knowledge for Gait Generation of a Six-legged Robot Using Genetic Programming 总被引:1,自引:0,他引:1
Kentarou Kurashige Toshio Fukuda Haruo Hoshino 《Journal of Intelligent and Robotic Systems》2003,38(1):121-134
There has been growing interest in motion planning problems for mobile robots. In this field, the main research is to generate a motion for a specific robot and task without previously acquired motions. However it is too wasteful not to use hard-earned acquired motions for other tasks. Here, we focus on a mechanism of reusing acquired motion knowledge and study a motion planning system able to generate and reuse motion knowledge. In this paper, we adopt a tree-based representation for expressing knowledge of motion, and propose a hierarchical knowledge for realizing a reuse mechanism. We construct a motion planning system using hierarchical knowledge as motion knowledge and using genetic programming as a learning method. We apply a proposed method for the gait generation task of a six-legged locomotion robot and show its availability with computer simulation. 相似文献
158.
Piiroinen Petri T. Dankowicz Harry J. Nordmark Arne B. 《Multibody System Dynamics》2003,10(2):147-176
The inherent dynamics of bipedal, passive mechanisms are studiedto investigate the relation between motions constrained to two-dimensional (2D)planes and those free to move in a three-dimensional (3D) environment. Inparticular, we develop numerical and analytical techniques usingdynamical-systems methodology to address the persistence and stabilitychanges of periodic, gait-like motions due to the relaxation ofconfiguration constraints and the breaking of problem symmetries. Theresults indicate the limitations of a 2D analysis to predictthe dynamics in the 3D environment. For example, it is shownhow the loss of constraints may introduce characteristically non-2Dinstability mechanisms, and how small symmetry-breaking terms may result inthe termination of solution branches. 相似文献
159.
Kyoungrae Cho Munsang Kim Jae-Bok Song 《Journal of Intelligent and Robotic Systems》2003,36(4):371-387
A pick-and-place operation in a 3-dimensional environment is a basic operation for humans and multi-purpose manipulators. However, there may be a difficult problem for such manipulators. Especially, if the object cannot be moved with a single grasp, regrasping, which can be a time-consuming process, should be carried out. Regrasping, given initial and final poses of the target object, is a construction of sequential transition of object poses that are compatible with two poses in the point of grasp configuration. This paper presents a novel approach for solving the regrasp problem. The approach consists of a preprocessing and a planning stage. Preprocessing, which is done only once for a given robot, generates a look-up table which has information on kinematically feasible task space of the end-effector throughout the entire workspace. Then, using this table, the planning automatically determines a possible intermediate location, pose and regrasp sequence leading from the pick-up to put-down grasp. With a redundant robot, it is shown experimentally that the presented method is complete in the entire workspace and can be implemented in real-time applications due to rapid regrasp planning time. The regrasp planner was combined with an existing path. 相似文献
160.