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71.
Moritoshi Yasunaga Noriyuki Aibe Yoshiki Yamaguchi Yorihisa Yamamoto Takaaki Awano Ikuo Yoshihara 《Artificial Life and Robotics》2008,12(1-2):219-222
Watching and tracking an object while seeing a much wider view is one of advantages of the eye system. We proposed and developed
a tracking camera system that mimics the eyes by using double-lens modules. In the system, a wide view is captured through
the wide-lens module, while the target in it is tracked and magnified through the telescopic lens module. Electronic circuits
for tracking control are implemented onto the reconfigurable VLSI or FPGA in order to embed the parallelism in the tracking
algorithm into the hardware. A successfully developed FPGA-based prototype performs high-speed tracking at the video-rate.
This work was present in part at the 12th International Symposium on Artificial Life and Robotics, Oita, Japan, January 25–27,
2007 相似文献
72.
Qi Gong 《Automatica》2007,43(1):184-189
In this paper we address the practical tracking problem for a class of nonlinear systems by dynamic output feedback control. Unlike most of the existing results where the unmeasurable states in the nonlinear vector field can only grow linearly, we allow higher-order growth of unmeasurable states. The proposed controller makes the tracking error arbitrarily small and demonstrates nice properties such as robustness to disturbances and universal property to reference signals. 相似文献
73.
Rinkenauer Gerhard; Osman Allen; Ulrich Rolf; Müller-Gethmann Hiltraut; Mattes Stefan 《Canadian Metallurgical Quarterly》2004,133(2):261
Lateralized readiness potentials (LRPs) were used to determine the stage(s) of reaction time (RT) responsible for speed-accuracy trade-offs (SATs). Speeded decisions based on several types of information were examined in 3 experiments, involving, respectively, a line discrimination task, lexical decisions, and an Erikson flanker task. Three levels of SAT were obtained in each experiment by adjusting response deadlines with an adaptive tracking algorithm. Speed stress affected the duration of RT stages both before and after the start of the LRP in all experiments. The latter effect cannot be explained by guessing strategies, by variations in response force, or as an indirect consequence of the pre-LRP effect. Contrary to most models, it suggests that SAT can occur at a late postdecisional stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
74.
Dynamics of the explosive growth of a vapor bubble in microgravity is investigated by direct numerical simulation. A front tracking/finite difference technique is used to solve for the velocity and the temperature field in both phases and to account for inertia, viscosity, and surface deformation. The method is validated by comparison of the numerical results with the available analytical formulations such as the evaporation of a one-dimensional liquid/vapor interface, frequency of oscillations of capillary waves, and other numerical results. Evolution of a three-dimensional vapor nucleus during explosive boiling is followed and a fine scale structure similar to experimental results is observed. Two-dimensional simulations yield a similar qualitative instability growth. 相似文献
75.
76.
77.
一种弧焊机器人实时激光扫描视觉系统 总被引:2,自引:0,他引:2
研制了一种小型高精度弧焊机器人实时激光扫描视觉系统,对其各项性能进行了测试,并进行了抗电弧光干扰试验,结果表明,此系统精度高,抗干扰能力强,检测范围宽,能广泛地应秀于机器人和自动化焊接中。 相似文献
78.
在对高速运动目标进行高精度的跟踪测量时 ,常采用高帧频电视跟踪系统。针对高帧频电视象元分辨率低、处理时间短、信噪比低的特点 ,对其定位跟踪算法进行了研究。 相似文献
79.
Real-time accurate hand path tracking and joint trajectory planning for industrial robots (I) 总被引:1,自引:0,他引:1
Previously, researchers raised the accuracy for a robot’s hand to track a specified path in Cartesian space mainly through
increasing the number of knots on the path and the number of the path’s segments, which results in the heavier online computational
burden for the robot controller. Aiming at overcoming this drawback, the authors propose a new kind of real-time accurate
hand path tracking and joint trajectory planning method. Through selecting some extra knots on the specified hand path by
a certain rule and introducing a sinusoidal function to the joint displacement equation of each segment, this method can greatly
raise the path tracking accuracy of robot’s hand and does not change the number of the path’s segments. It also does not increase
markedly the computational burden of robot controller. The result of simulation indicates that this method is very effective,
and has important value in increasing the application of industrial robots.
Foundation item: Foundation of the Robotics Laboratory, Chinese Academy of Sciences (No. RL200002)
Biography of the first author: TAN Guan-zheng, Dr., professor, born in Oct. 1962, majoring in artificial intelligence, robotics and automation. 相似文献
80.
Yan Shuicheng Wang Huan Liu Jianzhuang Tang Xiaoou Thomas S. Huang 《Frontiers of Computer Science in China》2007,1(4):407-412
The techniques for image analysis and classification generally consider the image sample labels fixed and without uncertainties.
The rank regression problem studied in this paper is based on the training samples with uncertain labels, which often is the
case for the manual estimated image labels. A core ranking model is designed first as the bilinear fusing of multiple candidate
kernels. Then, the parameters for feature selection and kernel selection are learned simultaneously by maximum a posteriori
for given samples and uncertain labels. The provable convergency Expectation Maximization (EM) method is used for inferring
these parameters in an iterative manner. The effectiveness of the proposed algorithm is finally validated by the extensive
experiments on age ranking task and human tracking task. The popular FG-NET and the large scale Yamaha aging database are
used for the age estimation experiments, and our algorithm outperforms those state-of-the-art algorithms ever reported by
other interrelated literatures significantly. The experiment result of human tracking task also validates its advantage over
conventional linear regression algorithm.
A short version of this paper appeared in ICME07. 相似文献