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   2504篇
  免费   96篇
  国内免费   14篇
电工技术   53篇
综合类   5篇
化学工业   548篇
金属工艺   76篇
机械仪表   79篇
建筑科学   66篇
矿业工程   9篇
能源动力   74篇
轻工业   282篇
水利工程   22篇
石油天然气   8篇
无线电   146篇
一般工业技术   429篇
冶金工业   486篇
原子能技术   20篇
自动化技术   311篇
  2023年   27篇
  2022年   29篇
  2021年   70篇
  2020年   35篇
  2019年   54篇
  2018年   76篇
  2017年   71篇
  2016年   98篇
  2015年   76篇
  2014年   94篇
  2013年   160篇
  2012年   140篇
  2011年   154篇
  2010年   104篇
  2009年   97篇
  2008年   92篇
  2007年   91篇
  2006年   68篇
  2005年   63篇
  2004年   46篇
  2003年   33篇
  2002年   45篇
  2001年   27篇
  2000年   25篇
  1999年   34篇
  1998年   137篇
  1997年   89篇
  1996年   74篇
  1995年   39篇
  1994年   33篇
  1993年   31篇
  1992年   19篇
  1990年   16篇
  1989年   10篇
  1988年   17篇
  1987年   10篇
  1986年   12篇
  1985年   21篇
  1984年   21篇
  1983年   17篇
  1982年   12篇
  1981年   20篇
  1980年   18篇
  1979年   16篇
  1978年   12篇
  1977年   17篇
  1976年   36篇
  1974年   11篇
  1973年   17篇
  1940年   10篇
排序方式: 共有2614条查询结果,搜索用时 0 毫秒
61.
Artificial bee colony (ABC) algorithm developed by Karaboga is a nature inspired metaheuristic based on honey bee foraging behavior. It was successfully applied to continuous unconstrained optimization problems and later it was extended to constrained design problems as well. This paper introduces an upgraded artificial bee colony (UABC) algorithm for constrained optimization problems. Our UABC algorithm enhances fine-tuning characteristics of the modification rate parameter and employs modified scout bee phase of the ABC algorithm. This upgraded algorithm has been implemented and tested on standard engineering benchmark problems and the performance was compared to the performance of the latest Akay and Karaboga’s ABC algorithm. Our numerical results show that the proposed UABC algorithm produces better or equal best and average solutions in less evaluations in all cases.  相似文献   
62.
63.
64.
65.
66.
The AUTOPIA program has been working on the development of intelligent autonomous vehicles for the last 10 years. Its latest advances have focused on the development of cooperative man?uvres based on communications involving several vehicles. However, so far, these man?uvres have been tested only on private tracks that emulate urban environments. The first experiments with autonomous vehicles on real highways, in the framework of the grand cooperative driving challenge (GCDC) where several vehicles had to cooperate in order to perform cooperative adaptive cruise control (CACC), are described. In this context, the main challenge was to translate, through fuzzy controllers, human driver experience to these scenarios. This communication describes the experiences deriving from this competition, specifically that concerning the controller and the system implemented in a Citröen C3.  相似文献   
67.
An increasing number of people are joining online social networks. By interacting with each other, network members influence one another’s opinion. These influencing effects can be utilized by marketing. A wave of influence can be triggered by addressing only a few opinion leaders in the network. Targeting the right opinion leaders is a big challenge. This paper presents a new approach which simulates the spread of opinions when influencing certain opinion leaders. In contrast to other approaches, the influencing effects are not assumed but revealed by real data. The principles of opinion formation are detected by ant mining algorithms before they are applied to simulate the spread of opinions. The approach is applied to an online gaming community and provides valuable insights for marketing.  相似文献   
68.
As the urgent need for efficient and sustainable energy usage becomes ever more apparent, interest in Smart Homes is on the rise. The SESAME-S project (SEmantic SmArt Metering – Services for Energy Efficient Houses) uses semantically linked data to actively assist end-consumers in making well-informed decisions and controlling their energy consumption. By integrating smart metering and home automation functionality, SESAME-S works to effectively address the potential mass market of end-consumers with an easily customizable solution that can be widely implemented in domestic or business environments, with expected savings of over 20?% from the total energy bill. The developed system is a basis for conceptualizing, demonstrating, and evaluating a variety of innovative end-consumer services and their user interface paradigms. In this paper, we present the SESAME-S system as a whole and discuss the semantically enabled services, demonstrating that such systems may have broad acceptance in the future. The data obtained through such systems will be invaluable for future global energy-efficiency strategies and businesses.  相似文献   
69.
High melting Mo-Si-B based alloys exhibit good mechanical properties and oxidation resistance at very high temperatures. The alloy composition Mo-9Si-8B (at.%) shows excellent oxidation behavior between 900°C–1,300°C as a consequence of protective silica scale formation. Below 900°C, a protective oxide layer does not form as a consequence of simultaneous and competitive Mo- and Si-oxide formation. Macro- and microalloying strategies as well as pre-treatment prior to oxidation in air were examined in order to determine their impact on the oxidation performance. Alloying with Cr is a suitable means for protective Cr-oxide scale formation at intermediate temperatures; adding small amounts of reactive elements was found to have a strong impact on the silica scale forming ability. Furthermore, the oxidation behavior can be controlled and enhanced by selective oxidation in oxygen-deficient atmospheres prior to exposure to air.  相似文献   
70.
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