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   2683篇
  免费   15篇
  国内免费   4篇
电工技术   158篇
综合类   7篇
化学工业   588篇
金属工艺   95篇
机械仪表   56篇
建筑科学   53篇
能源动力   135篇
轻工业   178篇
水利工程   35篇
石油天然气   1篇
无线电   288篇
一般工业技术   407篇
冶金工业   425篇
原子能技术   67篇
自动化技术   209篇
  2024年   12篇
  2023年   13篇
  2022年   25篇
  2021年   37篇
  2020年   28篇
  2019年   44篇
  2018年   23篇
  2017年   21篇
  2016年   43篇
  2015年   33篇
  2014年   62篇
  2013年   140篇
  2012年   114篇
  2011年   131篇
  2010年   90篇
  2009年   148篇
  2008年   121篇
  2007年   92篇
  2006年   88篇
  2005年   92篇
  2004年   73篇
  2003年   86篇
  2002年   63篇
  2001年   58篇
  2000年   61篇
  1999年   62篇
  1998年   159篇
  1997年   114篇
  1996年   78篇
  1995年   54篇
  1994年   46篇
  1993年   49篇
  1992年   36篇
  1991年   35篇
  1990年   19篇
  1989年   30篇
  1988年   28篇
  1987年   14篇
  1986年   17篇
  1985年   26篇
  1984年   22篇
  1983年   18篇
  1982年   16篇
  1981年   23篇
  1980年   27篇
  1979年   14篇
  1978年   18篇
  1977年   20篇
  1976年   26篇
  1972年   10篇
排序方式: 共有2702条查询结果,搜索用时 15 毫秒
131.
This paper introduces a human skill base control algorithm using artificial neural networks and fuzzy reasoning for an autonomous mobile robot. Neural networks are used to select a suitable motion control pattern in actual environments. The back propagation algorithm adjusts the weights of the neural networks so that the selected motion control pattern corresponds to the action, which is obtained by the operator's behavior decision skill. To realize the selected motion control pattern, the orientation angle and the speed of the mobile robot are determined by fuzzy reasoning in which fuzzy rules are also automatically tuned so as to simulate the operator's control skill. We have implemented and tested the proposed control algorithm on an autonomous mobile robot and some experimental results demonstrate the effectiveness of the proposed control algorithm for the autonomous mobile robot. © 2000 Scripta Technica, Electr Eng Jpn, 131(2): 30–39, 2000  相似文献   
132.
This paper describes the phenomenon of internal pressure‐rise due to arcs ignited between metal rod electrodes in air. First, the internal pressure‐rises in a closed chamber due to arcs were measured at currents within the range of 1 to 12.5 kA. The rod electrodes were made of copper, iron, and aluminum, and were 20 mm in diameter. The measurements showed that the maximum pressure‐rise distinctly differed with each electrode material at the same total arc energy, namely, the maximum pressure‐rise was the highest in the case of the aluminum electrode and was the lowest in the case of the iron electrode. Next, to quantitatively verify this difference, the internal pressure‐rise was estimated, taking into account the energy balance in the closed chamber on each electrode material. It was found that the estimated pressure‐rise approximately agreed with the above experimental results by taking into consideration oxidation reactions of the electrodes, melting and vaporization of the electrodes, and radiation loss of the arcs under certain realistic assumptions. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 174(4): 9–18, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21071  相似文献   
133.
We developed a root cause analysis (RCA) system for an enterprise IT system environment. In this paper, we propose a rule‐construction method that builds analysis rule data objects from general analysis rules and the topology information of the actual target IT environment. Using this method, the IT administrator can use the RCA system without any manual rule modifications. For the execution of the analysis, we introduce the certainty factor to realize robust analysis when the order and reachability of a fault event cannot be guaranteed.  相似文献   
134.
Abstract— This paper presents a new display device, which combines a digital backplane and a vertically aligned nematic liquid‐crystal layer. The device has 1280 × 720 pixels in a 0.7‐in.‐diagonal display area. In this paper, we present the concept of the new device and overview the performance of the device for a rear‐projection television application.  相似文献   
135.
Introducing the ways of cultivating mental balance, B. A. Wallace and S. L. Shapiro (see record 2006-12925-003) attempted to build bridges between Buddhism and psychology. Their systematic categorization of Buddhist teachings and extensive review of empirical support from Western psychology are valuable for future study. However, it remains a matter of concern that some more profound parts of Buddhist philosophy can be disregarded by focusing only on practical aspects of Buddhism within the context of mental health. In this comment, the authors briefly address four substantial themes to be considered: reality, identity, causality, and logicality. They suggest that the way to interpret Buddhism as techniques for well-being would certainly be viable in encouraging the study of Buddhist teachings in psychology. Yet, such attempts should not result in superficial imports and applications of Buddhist practices but give due weight to the deeper philosophical issues to build more solid bridges between Buddhism and psychology. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
136.
This paper tackles the problem of discovering subtle fall risks using skeleton clustering by multi-robot monitoring. We aim to identify whether a gait has fall risks and obtain useful information in inspecting fall risks. We employ clustering of walking postures and propose a similarity of two datasets with respect to the clusters. When a gait has fall risks, the similarity between the gait which is being observed and a normal gait which was monitored in advance exhibits a low value. In subtle fall risk discovery, unsafe skeletons, postures in which fall risks appear slightly as instabilities, are similar to safe skeletons and this fact causes the difficulty in clustering. To circumvent this difficulty, we propose two instability features, the horizontal deviation of the upper and lower bodies and the curvature of the back, which are sensitive to instabilities and a data preprocessing method which increases the ability to discriminate safe and unsafe skeletons. To evaluate our method, we prepare seven kinds of gait datasets of four persons. To identify whether a gait has fall risks, the first and second experiments use normal gait datasets of the same person and another person, respectively. The third experiments consider that how many skeletons are necessary to identify whether a gait has fall risks and then we inspect the obtained clusters. In clustering more than 500 skeletons, the combination of the proposed features and our preprocessing method discriminates gaits with fall risks and without fall risks and gathers unsafe skeletons into a few clusters.  相似文献   
137.
In 1998, Toyo Gosei Co. published a paper on the development of a new water‐soluble photopolymer of high sensitivity, PVA‐ARBB. In close co‐operation with LG. Philips Displays, the new material was further developed to be applicable in patterning the phosphor layer of a CRT screen. The new material shows about 3 times higher light sensitivity, gives 4–5% higher luminance, has no dark reaction, and is chromium‐free. It is the first chromium‐free photoresist used for phosphor patterning in CRT mass production. A comparison is presented between the conventional resist and the new resist. A survey is given of the most important process conditions.  相似文献   
138.
A molecular structure viewer program, MOSBY has been developed for studies that use atomic coordinates to understand the structures of protein molecules. The program is designed to be portable with a comprehensive user interface by our high-throughput graphics library. In addition, it cooperates with extension modules customized for individual research topics and analysis. For example, an electron density module loads and displays electron density maps derived in X-ray crystallographic analysis superimposed to an atomic model. A molecular dynamics module reads a trajectory file of the results of molecular dynamics calculations and animates the structure. These plug-in modules are devised to function without modification to the MOSBY program. For variations of analysis and calculations with atomic coordinates, the portability and extensibility illustrated by MOSBY play an important rule in scientific computational tools with active software development.  相似文献   
139.
The solid solubility of silicon and germanium in aluminium under pressure are investigated using the microscopic electronic theory based on pseudopotentials and using the virtual crystal approximation. Obtained results for the lattice constant and the solid solubility under pressure in the Al-Si and Al-Ge systems are in good agreement with the few available experimental data, in spite of our not introducing any adjustable parameter except for the lattice constant of pure aluminium crystal. The heat of solution and the pressure-volume relation in the Al-Si and Al-Ge systems are presented theoretically.  相似文献   
140.
Numerical solutions are obtained for natural convection heat transfer in an open channel with corrugated, isothermal confining walls. The channel is very long so that the fluid temperature approaches the wall temperature and the flow can be assumed to be periodically fully developed. The solutions are obtained by solving the full elliptic governing equations in a transformed coordinate system which maps the channel with corrugated walls onto a channel with flat walls. The periodic, fully developed Nusselt number for the corrugated channel is expressed by the relation Nu = CGrPr/(L/W) where Gr, Pr and L/W are the Grashof number, the Prandtl number and the aspect ratio, respectively, and C is a parameter which is a function of Gr, L/W and the corrugation angle θ. In the limiting case of θ = 0° (two flat walls), the parameter C approaches a constant value. This value is within 1.6% of the exact analytical result.  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