首页 | 官方网站   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   2558篇
  免费   185篇
  国内免费   3篇
工业技术   2746篇
  2024年   14篇
  2023年   45篇
  2022年   43篇
  2021年   121篇
  2020年   89篇
  2019年   89篇
  2018年   146篇
  2017年   104篇
  2016年   134篇
  2015年   111篇
  2014年   123篇
  2013年   466篇
  2012年   98篇
  2011年   106篇
  2010年   128篇
  2009年   139篇
  2008年   68篇
  2007年   50篇
  2006年   48篇
  2005年   21篇
  2004年   19篇
  2003年   15篇
  2002年   17篇
  2001年   76篇
  2000年   74篇
  1999年   73篇
  1998年   82篇
  1997年   78篇
  1996年   22篇
  1995年   7篇
  1994年   12篇
  1993年   11篇
  1992年   8篇
  1991年   5篇
  1990年   7篇
  1989年   3篇
  1988年   7篇
  1987年   3篇
  1985年   7篇
  1984年   11篇
  1983年   4篇
  1982年   6篇
  1981年   9篇
  1980年   7篇
  1979年   6篇
  1978年   8篇
  1977年   3篇
  1976年   3篇
  1973年   4篇
  1968年   4篇
排序方式: 共有2746条查询结果,搜索用时 78 毫秒
1.
2.
3.
Physically based simulation of human hair is a well studied and well known problem. But the “pure” physically based representation of hair (and other animation elements) is not the only concern of the animators, who want to “control” the creation and animation phases of the content. This paper describes a sketch-based tool, with which a user can both create hair models with different styling parameters and produce animations of these created hair models using physically and key frame-based techniques. The model creation and animation production tasks are all performed with direct manipulation techniques in real-time.  相似文献   
4.
The past decade may be regarded as the phase of the fundamental developments in fieldbus systems that were based on the OSI model. Today we are entering a second stage. It is the objective of this issue to present the current state and where the further developments will lead to. This introductory article is intended to give an overview on the subject.  相似文献   
5.
Recently appeared defects on high voltage cables have required an urgent evaluation of the impact of lightning strikes necessary. In some cases overvoltages between the copper wire screen of the cable and earth may appear which cause damages of the cablesheath. Field measurements with a classification of the voltage impulses at the copper wire screen have been made to evaluate the number of events. Additionally a numerical model was developed to study the effects of atmospheric discharges on underground cables with emphasis to the influence on the cablesheath. This numeric method was also applied to estimate the effectiveness of different protection arrangements. This contribution presents evaluation methods for overvoltages of cables and a model used firstly for calculating the stress caused by differential voltages and secondly to determinate the influence of protection measures.  相似文献   
6.
7.
8.
Qualitative-quantitative simulation is one of the most productive and promising research areas in Artificial Intelligence to emerge in recent years. This method provides an elegant way for an exhaustive analysis of uncertain dynamic systems. The application of the qualitative-quantitative simulation is shown in this paper. The important question about the stability of a quanlitatively described dynamical system is solved by a novel analytic method.  相似文献   
9.
10.
There is an appreciable amount of carbonaceous sedimentary phosphate deposits in the northern Africa and the Middle East which are expected to gain importance in the near future because of the depletion of the deposits in Florida. In many of the regions where phosphate deposits are found there is a shortage of fresh water, and sea is not very far. The use of sea water instead of fresh water in flotation of carbonaceous phosphate rock is successfully demonstrated. Thus an appreciable reduction in the operating cost and an ample amount of saving in the fresh water resources of the region is expected.  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-23

京公网安备 11010802026262号