全文获取类型
收费全文 | 200826篇 |
免费 | 18004篇 |
国内免费 | 13211篇 |
专业分类
电工技术 | 33261篇 |
技术理论 | 11篇 |
综合类 | 19804篇 |
化学工业 | 10274篇 |
金属工艺 | 7714篇 |
机械仪表 | 18536篇 |
建筑科学 | 18888篇 |
矿业工程 | 7975篇 |
能源动力 | 5467篇 |
轻工业 | 5043篇 |
水利工程 | 6562篇 |
石油天然气 | 6481篇 |
武器工业 | 2934篇 |
无线电 | 17504篇 |
一般工业技术 | 10687篇 |
冶金工业 | 8426篇 |
原子能技术 | 1467篇 |
自动化技术 | 51007篇 |
出版年
2024年 | 875篇 |
2023年 | 2329篇 |
2022年 | 3937篇 |
2021年 | 4826篇 |
2020年 | 5798篇 |
2019年 | 4561篇 |
2018年 | 4076篇 |
2017年 | 5807篇 |
2016年 | 6522篇 |
2015年 | 7194篇 |
2014年 | 13631篇 |
2013年 | 11567篇 |
2012年 | 14829篇 |
2011年 | 15881篇 |
2010年 | 11995篇 |
2009年 | 12264篇 |
2008年 | 12142篇 |
2007年 | 14902篇 |
2006年 | 13212篇 |
2005年 | 11552篇 |
2004年 | 9485篇 |
2003年 | 8351篇 |
2002年 | 6715篇 |
2001年 | 5567篇 |
2000年 | 4757篇 |
1999年 | 3815篇 |
1998年 | 2933篇 |
1997年 | 2555篇 |
1996年 | 2050篇 |
1995年 | 1655篇 |
1994年 | 1396篇 |
1993年 | 1003篇 |
1992年 | 820篇 |
1991年 | 612篇 |
1990年 | 469篇 |
1989年 | 426篇 |
1988年 | 305篇 |
1987年 | 168篇 |
1986年 | 115篇 |
1985年 | 118篇 |
1984年 | 163篇 |
1983年 | 124篇 |
1982年 | 118篇 |
1981年 | 85篇 |
1980年 | 59篇 |
1979年 | 73篇 |
1978年 | 48篇 |
1977年 | 48篇 |
1964年 | 13篇 |
1959年 | 14篇 |
排序方式: 共有10000条查询结果,搜索用时 9 毫秒
101.
102.
103.
To clarify whether motion information per se has a separable influence on action control, the authors investigated whether irrelevant direction of motion of stimuli whose overall position was constant over time would affect manual left-right responses (i.e., reveal a motion-based Simon effect). In Experiments 1 and 2, significant Simon effects were obtained for sine-wave gratings moving in a stationary Gaussian window. In Experiment 3, a direction-based Simon effect with random-dot patterns was replicated, except that the perceived direction of motion was based on the displacement of single elements. Experiments 4 and 5 studied motion-based Simon effects to point-light figures that walked in place--displays requiring high-level analysis of global shape and local motion. Motion-based Simon effects occurred when the displays could be interpreted as an upright human walker, showing that a high-level representation of motion direction mediated the effects. Thus, the present study establishes links between high-level motion perception and action. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
104.
105.
针对湘钢65t/h链条钢炉气煤混烧特点,设计了给水、燃烧、汽温调节,应用美国Honеywеll9000系列小型集散控制系统,保证了锅炉安全、经济运行,达到了节能目的。 相似文献
106.
The primary visual sources of depth and size information are binocular cues and motion parallax. Here, the authors determine the efficacy of these cues to control prehension by presenting them in isolation from other visual cues. When only binocular cues were available, reaches showed normal scaling of the transport and grasp components with object distance and size. However, when only motion parallax was available, only the transpont component scaled reliably. No additional increase in scaling was found when both cues were available simultaneously. Therefore, although equivalent information is available from binocular and motion parallax information, the latter may be of relatively limited use for the control of the grasp. Binocular disparity appears selectively important for the control of the grasp. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
107.
关于项目管理中施工进度控制的研究 总被引:5,自引:1,他引:4
阐述了项目管理中施工进度控制的地位与作用,分析了影响工程进度的因素,提出项目进度控制需做好的工作,以提高进度控制水平,确保合同工期的实现。 相似文献
108.
Backlash is one of the most important non-linearities that limit the performance of speed and position control in industrial, robotics, automotive, automation and other applications. The control of systems with backlash has been the subject of study since the 1940s. This survey reveals that surprisingly few control innovations have been presented since the early path breaking papers that introduced the describing function analysis of systems with backlash. Promising developments are however taking place using adaptive and non-linear control strategies. 相似文献
109.
110.
Ramon R. Costa Liu Hsu 《International Journal of Adaptive Control and Signal Processing》1992,6(1):19-33
A variable structure model reference adaptive controller (VS-MRAC) using only input and output measurements was recently proposed and shown to be globally asymptotically stable with superior transient behaviour and disturbance rejection properties. In this paper a singular perturbation approach is used in order to establish the robustness of the controller in the presence of unmodelled dynamics (parasitics) and disturbances. We develop a new Lyapunov-based technique to analyse the overall system and show that for sufficiently small parasitics the system remains stable and the output error is small in some sense. 相似文献