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   980篇
  免费   27篇
电工技术   26篇
综合类   1篇
化学工业   131篇
金属工艺   45篇
机械仪表   70篇
建筑科学   9篇
矿业工程   4篇
能源动力   11篇
轻工业   37篇
水利工程   28篇
石油天然气   15篇
无线电   107篇
一般工业技术   213篇
冶金工业   71篇
原子能技术   43篇
自动化技术   196篇
  2022年   17篇
  2021年   23篇
  2020年   20篇
  2019年   23篇
  2018年   28篇
  2017年   23篇
  2016年   35篇
  2015年   28篇
  2014年   44篇
  2013年   63篇
  2012年   62篇
  2011年   72篇
  2010年   40篇
  2009年   46篇
  2008年   50篇
  2007年   52篇
  2006年   24篇
  2005年   27篇
  2004年   24篇
  2003年   17篇
  2002年   20篇
  2001年   12篇
  2000年   11篇
  1999年   10篇
  1998年   15篇
  1997年   14篇
  1996年   19篇
  1995年   7篇
  1994年   10篇
  1993年   7篇
  1992年   8篇
  1990年   8篇
  1989年   7篇
  1988年   6篇
  1986年   7篇
  1984年   6篇
  1983年   6篇
  1981年   5篇
  1980年   9篇
  1979年   9篇
  1978年   5篇
  1977年   12篇
  1976年   7篇
  1974年   5篇
  1973年   6篇
  1972年   5篇
  1971年   6篇
  1969年   5篇
  1967年   5篇
  1966年   6篇
排序方式: 共有1007条查询结果,搜索用时 15 毫秒
31.
The results of studying the surface of 15- to 100-nm-thick bismuth films by atomic-force microscopy are reported. The near-linear character of the dependences of the average surface roughness and the average height of growth patterns on the film thickness is established. It is found that the average crystallite size increases, as the film thickness is increased. A slight dependence of the crystallite size on the film thickness is observed at thicknesses in the range of 27–70 nm.  相似文献   
32.
Traditional configuration-based product family modeling techniques do not yield favorable solutions for modeling the product families with the dominant product topology variations. This paper presents the case study for the modeling of variations of the product configuration, parameters, and topologies in mass production of custom windows and doors in a one-of-a-kind production (OKP) company. The case study is based on the object-oriented product family modeling framework we developed for OKP which is characterized by the dominant product variation by topology. The problem of variation in topology in our framework is solved by the manual model transformation in the computer-aided design module which creates a new metamodel of products with the desired topology and which is the basis for a further, automatic model transformation. Usage of our framework has a positive effect on the level of the product customizations and shortening of the leading time which helps OKP companies in obtaining a better position at the market. Our software solution for the designing and manufacturing of custom windows and doors based on our framework is implemented in more than 300 mostly small- and medium-sized enterprises. It proves our concept which can be used for the realization of the information systems for computer-aided one-of-a-kind production in the companies with a different production plan.  相似文献   
33.
34.
An intelligent optimization model aiming at off-line or pre-series optimization of the thermal curing cycle of polymer matrix composites is proposed and discussed. The computational procedure is based on the coupling of a finite element thermochemical process model, dynamic artificial neural networks and genetic algorithms. Objective of the optimization routine is the maximization of the composite degree of cure by the definition of the autoclave temperature. Obtained outcomes evidenced the capability of the method as well as its efficiency with respect to hard computing or experimental procedures.  相似文献   
35.
36.
This paper presents the results of the research concerning possibilities of applying artificial neural networks for fault diagnosis, state estimation, and prediction in the gas pipeline transmission network. The influence of several factors on accuracy of the feedforward neural networks so applied was considered. The emphasis was put on neural network's function as state estimator. The choice of the most informative features, the amount and sampling period of training data sets, as well as different configurations of neural networks were analyzed.  相似文献   
37.
38.
Stability of current characteristics of a field-emission cell is analyzed. Experimental and simulated results are presented.  相似文献   
39.
40.
The research was conducted with the aim to investigate the possibility of Farinograph, Extensograph and Amylograph values prediction with linear and/or multiple Mixolab regression models. In total, 163 flour samples were divided based on Machalanobis distances into three sets: prediction, validation and external sample set. Determination coefficients ranged from 0.145 to 0.640 for linear regression models and from 0.279 to 0.739 for multiple regression models. Internal and external validation of developed regression models was conducted. Testing of developed models resulted in a high share of samples for which predicted values were out of the ranges of method official reproducibility and a high share of samples for which predicted values were out of the quality level range obtained by analytical measurement. It was concluded that it is impossible to develop applicable regression models for prediction of Farinograph, Extensograph and Amylograph parameters on the basis of Mixolab values from standard protocol.  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