全文获取类型
收费全文 | 10080篇 |
免费 | 102篇 |
国内免费 | 1篇 |
专业分类
电工技术 | 139篇 |
综合类 | 5篇 |
化学工业 | 867篇 |
金属工艺 | 110篇 |
机械仪表 | 141篇 |
建筑科学 | 164篇 |
矿业工程 | 32篇 |
能源动力 | 104篇 |
轻工业 | 692篇 |
水利工程 | 42篇 |
石油天然气 | 23篇 |
无线电 | 794篇 |
一般工业技术 | 982篇 |
冶金工业 | 5262篇 |
原子能技术 | 109篇 |
自动化技术 | 717篇 |
出版年
2021年 | 47篇 |
2019年 | 45篇 |
2018年 | 50篇 |
2017年 | 57篇 |
2016年 | 73篇 |
2015年 | 51篇 |
2014年 | 82篇 |
2013年 | 183篇 |
2012年 | 164篇 |
2011年 | 226篇 |
2010年 | 194篇 |
2009年 | 206篇 |
2008年 | 227篇 |
2007年 | 234篇 |
2006年 | 202篇 |
2005年 | 202篇 |
2004年 | 186篇 |
2003年 | 167篇 |
2002年 | 142篇 |
2001年 | 148篇 |
2000年 | 163篇 |
1999年 | 283篇 |
1998年 | 1374篇 |
1997年 | 853篇 |
1996年 | 593篇 |
1995年 | 365篇 |
1994年 | 329篇 |
1993年 | 386篇 |
1992年 | 180篇 |
1991年 | 187篇 |
1990年 | 167篇 |
1989年 | 195篇 |
1988年 | 171篇 |
1987年 | 146篇 |
1986年 | 152篇 |
1985年 | 138篇 |
1984年 | 88篇 |
1983年 | 96篇 |
1982年 | 88篇 |
1981年 | 76篇 |
1980年 | 85篇 |
1979年 | 79篇 |
1978年 | 86篇 |
1977年 | 168篇 |
1976年 | 286篇 |
1975年 | 59篇 |
1974年 | 56篇 |
1973年 | 54篇 |
1972年 | 37篇 |
1971年 | 36篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Bloomfield R.E. Guerra S. Miller A. Masera M. Weinstock C.B. 《Security & Privacy, IEEE》2006,4(3):66-68
Critical systems are aptly named - from electric power to water and gas to the telephone system and the Internet, they're all critical to some aspect of our daily lives. We're a networked society and as such, it's important to both know whether critical systems are trustworthy and be able to communicate, review, and debate the level of trust achieved in them. In the safety domain, explicit safety cases are increasingly required by law, regulations, and standards. In this article, we outline what a small, international group of experts, spanning various disciplines in safety, security, reliability, and critical infrastructure, been doing with the International Working Group on Assurance Cases (for Security), what we hope to achieve, and where we go next. 相似文献
2.
The benefits of adhesively bonded structures are well known. However, the most significant factor limiting the extensive application of metal bonding in primary aerospace structures is the prevailing lack of confidence in its long term durability under hostile environmental conditions.1,2 相似文献
3.
Yanqing Ji Hao Ying John Yen Shizhuo Zhu Daniel C. Barth‐Jones Richard E. Miller R. Michael Massanari 《国际智能系统杂志》2007,22(8):827-845
Discovering unknown adverse drug reactions (ADRs) in postmarketing surveillance as early as possible is highly desirable. Nevertheless, current postmarketing surveillance methods largely rely on spontaneous reports that suffer from serious underreporting, latency, and inconsistent reporting. Thus these methods are not ideal for rapidly identifying rare ADRs. The multiagent systems paradigm is an emerging and effective approach to tackling distributed problems, especially when data sources and knowledge are geographically located in different places and coordination and collaboration are necessary for decision making. In this article, we propose an active, multiagent framework for early detection of ADRs by utilizing electronic patient data distributed across many different sources and locations. In this framework, intelligent agents assist a team of experts based on the well‐known human decision‐making model called Recognition‐Primed Decision (RPD). We generalize the RPD model to a fuzzy RPD model and utilize fuzzy logic technology to not only represent, interpret, and compute imprecise and subjective cues that are commonly encountered in the ADR problem but also to retrieve prior experiences by evaluating the extent of matching between the current situation and a past experience. We describe our preliminary multiagent system design and illustrate its potential benefits for assisting expert teams in early detection of previously unknown ADRs. © 2007 Wiley Periodicals, Inc. Int J Int Syst 22: 827–845, 2007. 相似文献
4.
5.
The object-oriented approach to integrating knowledge data, and models is examined. Under the object-oriented paradigm, everything is an object, which is itself an encapsulation of data and methods to manipulate and access the data within the object. Thus knowledge, data, and models can be defined as special kinds of objects. Active knowledge/data language (KDL), a functional object-oriented database system is considered, covering the active-KDL-type system and functions, and query-driven simulation 相似文献
6.
7.
8.
Bond Gary R.; Dietzen Laura L.; McGrew John H.; Miller Larry D. 《Canadian Metallurgical Quarterly》1995,40(2):75
Tested the hypothesis that Ss with severe mental illnesses would achieve better vocational outcomes with an accelerated approach to supported employment (AASE), as compared to gradual approaches (GA) with prevocational training. 86 Ss (mean age 35.1 yrs) with a diagnosis of a serious mental illness, were randomly assigned to either the AASE, or the GA, which included a minimum of 4 mo prevocational training. Data were obtained on indicators of vocational outcomes over 2 yrs, and for a limited number of Ss (n=36), during the 4th yr of inception into the program. Initially, only 5% of Ss preferred prevocational training. After 1 yr, AASE Ss showed better outcomes for a range of indicators, including achievement of competitive employment, duration of employment and mean earnings. During the 4th yr, 59% of these Ss were competitively employed, as compared to only 6% of GA Ss. Rehabilitation is more effective using AASE than GA. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
The use of conventional ultrasound systems to image the upper airway has been limited because ultrasound energy is attenuated by the air column. In an attempt to study upper airway geometry, we developed a computer controlled bi-directional ultrasound system which combines two conventional ultrasound devices with computer image processing to yield images of upper airway structures. Human studies and cadaver studies were performed to evaluate the system. Images acquired by the bi-directional ultrasound system were comparable to images from 3D volume rendered CT scans. This system may provide valuable data in the study of upper airway physiology and pathology. 相似文献
10.
The author explains from an engineering standpoint, how some of the camcorder components work. He discusses the solid-state image sensor, the photodetector, scanning, the shutter frame rate, optics, the recording mechanism, the viewfinder, special effects, and automatic features. Motion detection, discrimination, and compensation are also covered. Recommendations as to which features are most useful are made 相似文献