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   9848篇
  免费   210篇
  国内免费   9篇
电工技术   103篇
综合类   6篇
化学工业   1425篇
金属工艺   113篇
机械仪表   322篇
建筑科学   268篇
矿业工程   28篇
能源动力   146篇
轻工业   1033篇
水利工程   118篇
石油天然气   16篇
无线电   924篇
一般工业技术   1222篇
冶金工业   3352篇
原子能技术   108篇
自动化技术   883篇
  2022年   79篇
  2021年   159篇
  2020年   94篇
  2019年   105篇
  2018年   95篇
  2017年   123篇
  2016年   101篇
  2015年   97篇
  2014年   142篇
  2013年   385篇
  2012年   238篇
  2011年   335篇
  2010年   284篇
  2009年   298篇
  2008年   342篇
  2007年   307篇
  2006年   300篇
  2005年   252篇
  2004年   217篇
  2003年   231篇
  2002年   226篇
  2001年   185篇
  2000年   176篇
  1999年   209篇
  1998年   778篇
  1997年   492篇
  1996年   428篇
  1995年   303篇
  1994年   253篇
  1993年   258篇
  1992年   114篇
  1991年   131篇
  1990年   138篇
  1989年   137篇
  1988年   142篇
  1987年   138篇
  1986年   109篇
  1985年   133篇
  1984年   95篇
  1983年   103篇
  1982年   71篇
  1981年   90篇
  1980年   70篇
  1979年   80篇
  1978年   70篇
  1977年   110篇
  1976年   201篇
  1975年   74篇
  1974年   71篇
  1973年   64篇
排序方式: 共有10000条查询结果,搜索用时 187 毫秒
141.
142.
Previous research has established the connection between the way in which children interact with objects and the potential early identification of children with autism. Those findings motivate our own work to develop "smart toys," objects embedded with wireless sensors that are safe and enjoyable for very small children, that allow detailed interaction data to be easily recorded. These sensor-enabled toys provide opportunities for autism research by reducing the effort required to collect and analyze a child’s interactions with objects. In the future, such toys may be a useful part of clinical and in-home assessment tools. In this paper, we discuss the design of a collection of smart toys that can be used to automatically characterize the way in which a child is playing. We use statistical models to provide objective, quantitative measures of object play interactions. We also developed a tool to view rich forms of annotated play data for later analysis. We report the results of recognition experiments on more than fifty play sessions conducted with adults and children as well as discuss the opportunities for using this approach to support video annotation and other applications.  相似文献   
143.
Economic dispatch is carried out at the energy control center to find out the optimal output of thermal generating units such that power balance criterion is met, unit operating limits are satisfied and the fuel cost is minimized. With growing environmental awareness and strict government regulations throughout the world, it has become essential to optimize not only the total fuel cost but also the harmful emissions, both, under static as well as dynamic conditions. The static environment economic dispatch finds the optimal output of generating units for a fixed load demand at a given time, while the dynamic environmental economic dispatch schedules the output of online generators with changing power demands over a certain time period (normally one day) so as to minimize these two conflicting objectives, simultaneously. In this paper, the price penalty factor approach is employed for simultaneous minimization of cost and emission. The generator ramp rate constraints, non-convex and discontinuous nature of cost function and the large number of generators in practical power plants, make this problem very difficult to solve. Here, a fuzzy ranking approach is employed to identify the solution which offers the best compromise between cost and emission objectives.  相似文献   
144.
Advances in computational geometric modeling, imaging, and simulation let researchers build and test models of increasing complexity, generating unprecedented amounts of data. As recent research in biomedical applications illustrates, visualization will be critical in making this vast amount of data usable; it's also fundamental to understanding models of complex phenomena.  相似文献   
145.
In recent years, great progress has been made in the development of computer-based technologies that support the manufacturing industries. Those concerned with advanced manufacturing technology (AMT) are becoming increasingly aware of the fundamental importance of human organisational issues for the successful development, implementation, operation and maintenance of AMT. The discipline of industrial ergonomics and occupational occupational psychology, therefore, have a significant contribution to make in this field. This paper introduces the special issue, Ergonomics Matters in AMT, and presents a discussion of some of the future directions of AMT and the likely implications for ergonomics research.  相似文献   
146.
Consumer confidence is at its lowest ebb since 1980. Economic growth is at a standstill & unemployment & inflation are both rising. Here's a front-line report from more than three dozen operators who are fending off the recession's dual pressures of slow sales & rising costs. They are using discount pricing, partnering with vendors, setting pay for performance standards & a variety of other recession-beating practices.  相似文献   
147.
148.
149.
150.
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