全文获取类型
收费全文 | 245990篇 |
免费 | 24404篇 |
国内免费 | 11794篇 |
专业分类
电工技术 | 36913篇 |
技术理论 | 29篇 |
综合类 | 27202篇 |
化学工业 | 11134篇 |
金属工艺 | 8585篇 |
机械仪表 | 21401篇 |
建筑科学 | 27290篇 |
矿业工程 | 9819篇 |
能源动力 | 8927篇 |
轻工业 | 5214篇 |
水利工程 | 6966篇 |
石油天然气 | 7200篇 |
武器工业 | 3957篇 |
无线电 | 24861篇 |
一般工业技术 | 12541篇 |
冶金工业 | 7344篇 |
原子能技术 | 2431篇 |
自动化技术 | 60374篇 |
出版年
2025年 | 43篇 |
2024年 | 3400篇 |
2023年 | 3331篇 |
2022年 | 5094篇 |
2021年 | 6129篇 |
2020年 | 6598篇 |
2019年 | 5044篇 |
2018年 | 4297篇 |
2017年 | 5857篇 |
2016年 | 6877篇 |
2015年 | 7926篇 |
2014年 | 15247篇 |
2013年 | 13012篇 |
2012年 | 17974篇 |
2011年 | 18927篇 |
2010年 | 14394篇 |
2009年 | 14491篇 |
2008年 | 14861篇 |
2007年 | 18786篇 |
2006年 | 16820篇 |
2005年 | 15024篇 |
2004年 | 12354篇 |
2003年 | 11140篇 |
2002年 | 8467篇 |
2001年 | 7087篇 |
2000年 | 5851篇 |
1999年 | 4744篇 |
1998年 | 3508篇 |
1997年 | 2882篇 |
1996年 | 2510篇 |
1995年 | 2132篇 |
1994年 | 1772篇 |
1993年 | 1196篇 |
1992年 | 1039篇 |
1991年 | 739篇 |
1990年 | 589篇 |
1989年 | 492篇 |
1988年 | 365篇 |
1987年 | 205篇 |
1986年 | 130篇 |
1985年 | 154篇 |
1984年 | 133篇 |
1983年 | 104篇 |
1982年 | 79篇 |
1981年 | 67篇 |
1980年 | 54篇 |
1979年 | 51篇 |
1978年 | 34篇 |
1977年 | 29篇 |
1976年 | 26篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
131.
132.
Naoji Shiroma Ryo Miyauchi Akira Nagafusa Youhei Haga Fumitoshi Matsuno 《Advanced Robotics》2015,29(3):149-163
In robot teleoperation, a robot works as a physical agent at a remote site for a robot operator. There are mainly two tasks in robot teleoperation using camera images: environment recognition using visual information and robot control according to the recognition. In this paper, we propose a gaze direction based vehicle teleoperation method with an omnidirectional image stabilization and an automatic body rotation control. In the proposed method, we manage above two tasks in the same manner that are usually treated separately. This method is an intuitive vehicle teleoperation method where an operator do not need to have concern about vehicle body orientations and can absorb differences of vehicle driving mechanisms. That is, this method frees an operator from being bothered from controlling a vehicle and the operator can concentrate on where he/she intends to go. This method mainly consists of two technologies: an omnidirectional image stabilization technology and automatic body rotation control. The conducted experiments show effectiveness of the proposed method. 相似文献
133.
Kensei Hiwaki 《控制论与系统》2015,46(6-7):588-604
This article argues for a theoretical framework of alternative economics pertinent to Sustainable Development. The alternative economics requires an appropriate belief/value system based on a dynamic, sound and holistic society-specific culture (abbreviated as “Culture”). To represent the Culture-based belief/value system, a general framework for overarching Integral Harmony is introduced as an appropriate social value system for a paradigm shift toward sustainability. Such a social value system is now related to the value premises of the alternative economics. Then, the framework of alternative economics is explained in terms of basic theoretical construct that is simplified as a summary equation comprising value and real aspects. Finally, a typical working of the alternative economics is demonstrated diagrammatically as constant interactions of the value aspect and the real aspect (abbreviated as “Value-Real Interactions”). 相似文献
134.
港口油库安全监控系统是在油库区域内按规范设置可燃、有毒气体监测探头报警装置,能够全面检测油库区域气体浓度情况,一旦超过预警值,立即进行自动报警至监控中心,并结合实时的气象监测(如风速、风向、温湿度、气压等气象状况)进行事故风险评估,预测可燃有毒气体危险危害扩散范围,从而采取有效防范措施,避免事故的发生。 相似文献
135.
136.
燃气轮机驱动的压缩机组被广泛地应用在天然气长输管道,其控制系统优化技术的大范围深度应用在管道行业尚数首次,及时消除生产瓶颈的同时,也为涉及燃机的控制专业同行提供了技术借鉴,更重要的是为管道行业燃机运行提供了安全保障。 相似文献
137.
索荣华 《数字社区&智能家居》2013,(11):7013-7016
长期以来,宁夏司法警官职业学院各种信息通过Office软件来存储,处理,在信息的更新,共享,查询,版本控制上等方面存在很多问题,管理这些信息比较繁琐,并且信息很难共享,因此学院急需一套信息管理系统来管理这些信息。该文对宁夏司法警官职业学院学生信息管理系统的项目立项、用户需求征询、设计开发、测试实施做了一个比较全面的概述。 相似文献
138.
Floc architecture of bioflocculation sediment by ESEM and CLSM 总被引:1,自引:0,他引:1
Sediment flocculation is a critical component for the understanding of cohesive sediment dynamics. Traditionally, the referred study has largely been devoted to forming mechanism, influencing factors and physicochemical sediment conditions of all kinds of organic-flocculation and inorganic-flocculation. However, during the last decade, the bioflocculation of sediment by biological activity has been given increasing attention. But most studies have focused on the interrelations between biological and sedimentological variables. With the assistance of a newly developed field kit and correlative microscopy (which includes environmental scanning electron microscopy and confocal laser scanning microscopy), this article begins to bridge the resolution gap between sediment particles and biological activities as well as its metabolic products biofilm, in order to better understand the role of polymeric material biofilm in floc ultrastructure and outward floc behavior of bioflocculation sediment. Results have demonstrated that bioflocculation sediment was observed to be composed of complex networks of biofilm and appeared to be of complicated physical floc structures. The biofilm was found to embed particles and permeate the void space, representing the dominant physical bridging mechanism of the flocs and contributed to the extensive surface area, architecture characteristics, and mechanical properties of bioflocculation sediment. 相似文献
139.
闫锦秀 《网络安全技术与应用》2013,(11):13-14
随着高新科学技术的发展,互联网的规模也不断扩大.人们对互联网需求也越来越多,而现有的网络体系结构开始难以满足人们的需求.本文主要通过讨论现今网络体系结构存在的问题,对相关技术进行研究. 相似文献
140.
Michael Breaks 《New Review of Information Networking》2013,18(2):67-68
The process undertaken by an information seeker, in order to form relevance decisions regarding documents, is defined as “Document Triage.” To better facilitate users’ needs in their triage activities, interactive interfaces have begun to evolve within on-line academic repositories. In order to complement current work on interface design and interaction, and produce custom guidelines to inform the creation of triage interfaces, we examine how interfaces that alter the document presentation and structure affect information seekers’ visual and navigational attention. We present a set of heuristics for both creating and evaluating such interfaces. 相似文献