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   4231篇
  免费   187篇
  国内免费   123篇
电工技术   126篇
综合类   431篇
化学工业   216篇
金属工艺   27篇
机械仪表   72篇
建筑科学   257篇
矿业工程   52篇
能源动力   52篇
轻工业   173篇
水利工程   49篇
石油天然气   60篇
武器工业   13篇
无线电   139篇
一般工业技术   180篇
冶金工业   2116篇
原子能技术   17篇
自动化技术   561篇
  2023年   21篇
  2022年   80篇
  2021年   86篇
  2020年   62篇
  2019年   66篇
  2018年   67篇
  2017年   73篇
  2016年   64篇
  2015年   86篇
  2014年   145篇
  2013年   127篇
  2012年   208篇
  2011年   304篇
  2010年   312篇
  2009年   311篇
  2008年   255篇
  2007年   291篇
  2006年   298篇
  2005年   283篇
  2004年   275篇
  2003年   267篇
  2002年   208篇
  2001年   179篇
  2000年   43篇
  1999年   22篇
  1998年   19篇
  1997年   22篇
  1996年   16篇
  1995年   18篇
  1994年   12篇
  1992年   9篇
  1991年   9篇
  1989年   10篇
  1987年   9篇
  1986年   10篇
  1985年   9篇
  1984年   9篇
  1979年   12篇
  1966年   13篇
  1965年   9篇
  1964年   16篇
  1963年   21篇
  1962年   8篇
  1961年   20篇
  1960年   12篇
  1959年   15篇
  1958年   12篇
  1957年   15篇
  1956年   8篇
  1955年   22篇
排序方式: 共有4541条查询结果,搜索用时 0 毫秒
1.
Ten areas of health knowledge were investigated in 2 studies, 1 of college students (N=169) and 1 of adults from the community (ages 19-70; N=176). Measures assessed knowledge of aging, orthopedic/ dermatological concerns, common illnesses, childhood/early life, serious illnesses, mental health, nutrition, reproduction, safety, and treatment of illness/disease. Significant gender differences favoring women were found for most areas of health knowledge, especially reproduction and early life. Results showed that cognitive ability accounted for the most variance in health knowledge with nonability (personality and interest traits) and demographic variables accounting for smaller but significant amounts of variance across most knowledge domains. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
2.
For decades, the marketing guidelines of enterprise software providers have focused on those managers who are likely to be more innovative in adopting new information systems. The current study argues that this approach demands improvements for two reasons: (1) this tactic may be biased, since past studies have only examined the single trait of innovativeness and its impact on an individual adoption intention and (2) the organisational implementation intention might be more important than the individual adoption intention, but the former has been largely ignored in the existing literature. Based on the case of business intelligence (BI) systems and data from 62 senior managers, this study is a pioneer in that it empirically reveals that managers’ individual adoption intention is distinct from their organisational implementation intention. Further, while managers’ innovativeness may be a significant determinant of their individual adoption intention towards BI systems, the issue of whether managers actually implement BI systems in their organisations is dominated by their involvement characteristics. Fruitful suggestions are proposed for practitioners and scholars.  相似文献   
3.
This paper resolves the problem of predicting as well as the best expert up to an additive term of the order o(n), where n is the length of a sequence of letters from a finite alphabet. We call the games that permit this weakly mixable and give a geometrical characterisation of the class of weakly mixable games. Weak mixability turns out to be equivalent to convexity of the finite part of the set of superpredictions. For bounded games we introduce the Weak Aggregating Algorithm that allows us to obtain additive terms of the form .  相似文献   
4.
The article aims to evaluate the consumer response to a reduction in the electricity tariffs as a hourly economic signal for the case of an electric utility in the state of Rio Grande do Sul, southern Brazil. Using Differences-in-differences method, the results were robust in showing that the change in the economic signal increased up to 81.01% the consumption at the time influenced by the change, improving the way in which the company's assets are used, in addition to reducing fuel oil consumption by users.  相似文献   
5.
Some students (base group) played the Circuit Game, a 10-level computer-based learning activity intended to help students learn how electrical circuits work. Other students (competition group) played the same game but with competition features added - including a score bar showing performance on each level, the opportunity to earn one ticket per level if a performance criterion is met, and the opportunity to win a prize based on the number of tickets earned. On a retention test given after the game, the competition group remembered significantly more than the base group (d = 0.47). On an embedded transfer test constituting the final level of the game, the groups did not differ significantly. However, on the transfer test there was a significant gender by group interaction in which men performed worse in the competition group than the base group (d = −0.54) and women performed better in the competition group than the base group (d = 0.24). Overall, adding game-like features to a computer-based learning activity caused students to pay attention to game details but did not motivate students - particularly men - to learn more deeply.  相似文献   
6.
Offshore outsourcing to vendors in foreign countries causes unique challenges which need to be understood and managed effectively. This paper explores cultural differences in IS offshoring arrangements involving German client organizations that outsource application development activities to Indian vendors. For this purpose, a research framework is developed based on both theoretical considerations and specific empirical observations from multiple case studies. The goal is to (1) explore the nature of cultural differences in offshore outsourcing arrangements in depth and to (2) analyze the relationship between those cultural differences and offshore outsourcing success. Based on the case findings, implications and practices for the management of offshore development projects are outlined. The results indicate that cultural differences in terms of power distance, IS designer values, and an active versus passive working attitude critically affect several dimensions of relationship quality, thereby influencing offshore outsourcing success. A clear definition of roles and mechanisms, strong leadership, and an active management of culture by adapting to either the client’s or the vendor’s national culture appeared to be effective ways to manage cultural differences.
Armin HeinzlEmail:
  相似文献   
7.
In recent years, educators and students are increasingly employing online collaboration applications such as Google Docs™ and PBWorks™ for group projects and assignments. Yet, the effectiveness of these emerging technologies has not been rigorously examined. Anchoring upon and informed by the existing literature, two design characteristics – sociability and visibility, and two human characteristics – gender and age, are focused on, which are salient in online collaboration applications. A field experiment was conducted to examine the direct and moderating effects of design and human characteristics on learning outcomes. The research found that sociability improved process satisfaction and positive social environment while visibility enhanced academic performance and solution satisfaction of learners. Males had higher solution satisfaction while older learners had higher academic performance. Moderating effects were also found. Both theoretical and practical implications are drawn. In particular, a rubric for online collaboration application selection for academic performance is conceived. This study provides empirical support for online collaboration application effectiveness in education which will augur well for future adoption, use and evolution.  相似文献   
8.
《Ergonomics》2012,55(3):461-481
Computer programming knowledge can be classified into five levels of abstraction: objective, conceptual, functional, logical, and physical. An experiment was carried out to determine whether the mastering of knowledge at different levels of abstraction changed with the level of skill. Ten experts and ten novices in C computer programming participated in the experiment. The subjects' knowledge at the five levels of abstraction was tested through 20 multiple-choice questions. The experimental results indicated that knowledge differences between experts and novices at an abstract level or a concrete level depended on what abstract or concrete knowledge was implied. Experts had better abstract knowledge than novices at the conceptual and functional levels but not at the objective level. Experts had better concrete knowledge than novices at the physical level but not at the logical level. The classification of computer programming knowledge in levels of abstraction and the experimental results helped in clarifying a general finding from previous studies that experts had better abstract knowledge than novices.  相似文献   
9.
《Ergonomics》2012,55(11):1285-1297

Human factors and ergonomics research could benefit from focusing more strongly on individual differences – especially trait variables. The present study suggests the analysis of moderator effects as a promising way to enhance understanding of trait variables and process control performance. Process control performance was studied by analysing moderator effects of general mental ability (GMA) and need for cognition (NC) on risky decision-making (RDM) and performance. Fifty engineering students were trained on a process control task using a computer-based simulation for three hours and tested twice thereafter. Risky decision-making was measured using a computerised gambling task while GMA and NC were assessed with questionnaires. Risky decision-making in interaction with each GMA and NC explained variance in performance over and above variance explained by the single effects. In conclusion, the analysis of moderator effects between individual difference variables and process control performance seems promising.

Practitioner Summary: Individual difference variables affect learning and performance, but have often not been studied to any great extent in human factors research. This article suggests a promising approach to studying individual differences – moderator analyses – and illustrates how such differences can lead to a better understanding of what determines process control performance.  相似文献   
10.
Chen JY  Barnes MJ 《Ergonomics》2012,55(9):1043-1058
A military targeting environment was simulated to examine the effects of an intelligent route-planning agent RoboLeader, which could support dynamic robot re-tasking based on battlefield developments, on the performance of robotics operators. We manipulated the level of assistance (LOAs) provided by RoboLeader as well as the presence of a visualisation tool that provided feedback to the participants on their primary task (target encapsulation) performance. Results showed that the participants' primary task benefited from RoboLeader on all LOAs conditions compared to manual performance; however, visualisation had little effect. Frequent video gamers demonstrated significantly better situation awareness of the mission environment than did infrequent gamers. Those participants with higher spatial ability performed better on a secondary target detection task than did those with lower spatial ability. Finally, participants' workload assessments were significantly lower when they were assisted by RoboLeader than when they performed the target entrapment task manually. Practitioner Summary: This study demonstrated the utility of an intelligent agent for enhancing robotics operators' supervisory control performance as well as reducing their workload during a complex urban scenario involving moving targets. The results furthered the understanding of the interplay among level-of-autonomy, multitasking performance and individual differences in military tasking environments.  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