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   39591篇
  免费   4634篇
  国内免费   3557篇
电工技术   3505篇
技术理论   10篇
综合类   5589篇
化学工业   676篇
金属工艺   392篇
机械仪表   1945篇
建筑科学   2500篇
矿业工程   1137篇
能源动力   338篇
轻工业   536篇
水利工程   1117篇
石油天然气   509篇
武器工业   983篇
无线电   6257篇
一般工业技术   1980篇
冶金工业   1488篇
原子能技术   82篇
自动化技术   18738篇
  2024年   147篇
  2023年   429篇
  2022年   875篇
  2021年   1083篇
  2020年   1164篇
  2019年   842篇
  2018年   779篇
  2017年   1062篇
  2016年   1306篇
  2015年   1503篇
  2014年   2852篇
  2013年   2603篇
  2012年   3176篇
  2011年   3221篇
  2010年   2483篇
  2009年   2730篇
  2008年   2922篇
  2007年   3158篇
  2006年   2849篇
  2005年   2504篇
  2004年   2166篇
  2003年   1905篇
  2002年   1366篇
  2001年   1136篇
  2000年   871篇
  1999年   564篇
  1998年   387篇
  1997年   314篇
  1996年   258篇
  1995年   201篇
  1994年   186篇
  1993年   135篇
  1992年   93篇
  1991年   76篇
  1990年   46篇
  1989年   53篇
  1988年   43篇
  1987年   25篇
  1986年   23篇
  1985年   27篇
  1984年   37篇
  1983年   29篇
  1982年   16篇
  1981年   13篇
  1980年   17篇
  1979年   15篇
  1977年   8篇
  1965年   10篇
  1964年   12篇
  1961年   7篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
121.
李涛  乔丰伟 《河南冶金》2003,11(2):17-18,33
近年来,为了更好地应对新的市场挑战,钢铁企业都在积极推进信息化建设,以实现管理提升、效益提升的目标。本文结合安钢集团的实际情况,对信息化实施策略进行初步的探讨,希望能对企业信息化建设有所借鉴。  相似文献   
122.
To clarify whether motion information per se has a separable influence on action control, the authors investigated whether irrelevant direction of motion of stimuli whose overall position was constant over time would affect manual left-right responses (i.e., reveal a motion-based Simon effect). In Experiments 1 and 2, significant Simon effects were obtained for sine-wave gratings moving in a stationary Gaussian window. In Experiment 3, a direction-based Simon effect with random-dot patterns was replicated, except that the perceived direction of motion was based on the displacement of single elements. Experiments 4 and 5 studied motion-based Simon effects to point-light figures that walked in place--displays requiring high-level analysis of global shape and local motion. Motion-based Simon effects occurred when the displays could be interpreted as an upright human walker, showing that a high-level representation of motion direction mediated the effects. Thus, the present study establishes links between high-level motion perception and action. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
123.
虚假的会计信息,将严重扭曲股票的价值,扰乱资本市场秩序,侵害投资者的利益。笔者就会计信息失真的原因进行了分析,并就如何防范进行了探讨。  相似文献   
124.
In 2 studies, the relation between measures of self-assessed health (SAH) and automatic processing of health-relevant information was investigated. In Study 1, 84 male and 86 female undergraduate students completed a modified Stroop task. Results indicated that participants with poorer SAH showed enhanced interference effects for illness versus non-illness words. In Study 2, 27 male and 30 female undergraduate students completed a self-referent encoding task. Results offered a conceptual replication and extension of Study 1 by confirming the specificity of the relation between SAH measures and automatic processing of health (vs negative or positive general trait) information. These studies provide evidence that individual differences in SAH are reflected in schematic processing of health-relevant information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
125.
阐述智能建筑的电气设计及施工中各电气设计子项的具体解决方案,以及弱电竖井设置中要注意的一些问题。  相似文献   
126.
This article argues that it is not uncommon for people forming justice judgments to lack information that is most relevant in the particular situation. In information-uncertain conditions, people may therefore construct justice judgments by relying on how they feel about the events they have encountered, and justice judgments may hence be strongly influenced by affect information. Findings show that in information-uncertain conditions, the affective states that people had been in prior and unrelated to the justice event indeed strongly influenced their justice judgments. These findings thus reveal that in situations of information uncertainty, people's judgments of justice can be very subjective, susceptible to affective states that have no logical relationship with the justice judgments they are constructing. Implications for the social psychology of justice and the literature on social cognition and affect are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
127.
城市燃气管网GIS系统的开发   总被引:1,自引:1,他引:0  
随着我国天然气工业的不断发展,对于城市天然气管网的智能化管理已经作为一个全新的课题出现在燃气企业里。过去所使用的MIS系统(Management Information System),无论从效率、准确度、智能程度上讲,都已经不能满足目前城市燃气管网的精确管理。因此地理信息系统(Geography Information System,简称GIS系统)作为一种新的计算机管理系统应运而生,其主要特点是:有精确的管理、有标准的地图提供直接判断、空间关系与实物对应明确、管理直观。文章以企业对管理系统的需求以及技术可行性为出发点,阐述了GIS系统应具有的基本性能;同时结合燃气工程技术的发展,对燃气GIS系统做了应用开发研究;此外还对现阶段部分燃气GIS信息系统的不足做出了分析。  相似文献   
128.
叙述在数字电视平台上建立广电网络信息业务平台的设想,并提出建立湖州广电网络信息业务平台的几点看法。  相似文献   
129.
Information-Based Evaluation Criterion for Classifier's Performance   总被引:2,自引:0,他引:2  
Kononenko  Igor  Bratko  Ivan 《Machine Learning》1991,6(1):67-80
In the past few years many systems for learning decision rules from examples were developed. As different systems allow different types of answers when classifying new instances, it is difficult to appropriately evaluate the systems' classification power in comparison with other classification systems or in comparison with human experts. Classification accuracy is usually used as a measure of classification performance. This measure is, however, known to have several defects. A fair evaluation criterion should exclude the influence of the class probabilities which may enable a completely uninformed classifier to trivially achieve high classification accuracy. In this paper a method for evaluating the information score of a classifier's answers is proposed. It excludes the influence of prior probabilities, deals with various types of imperfect or probabilistic answers and can be used also for comparing the performance in different domains.  相似文献   
130.
Intelligent SQL     
Intelligent SQL is an intelligent database engine interface language which incorporates object-oriented, inferencing, and multi-media constructs. It is intended to be a powerful extension of existing SQL dialects. It also provides querying capabilities for object-oriented databases. Intelligent SQL was prototyped at Ashton-Tate. This paper discusses the main features of Intelligent SQL.  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