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   13136篇
  免费   1457篇
  国内免费   1027篇
电工技术   500篇
技术理论   1篇
综合类   1084篇
化学工业   1998篇
金属工艺   384篇
机械仪表   545篇
建筑科学   1578篇
矿业工程   148篇
能源动力   467篇
轻工业   801篇
水利工程   386篇
石油天然气   238篇
武器工业   107篇
无线电   929篇
一般工业技术   2263篇
冶金工业   689篇
原子能技术   245篇
自动化技术   3257篇
  2024年   93篇
  2023年   377篇
  2022年   655篇
  2021年   670篇
  2020年   569篇
  2019年   520篇
  2018年   477篇
  2017年   551篇
  2016年   553篇
  2015年   513篇
  2014年   788篇
  2013年   922篇
  2012年   799篇
  2011年   869篇
  2010年   627篇
  2009年   689篇
  2008年   689篇
  2007年   729篇
  2006年   602篇
  2005年   558篇
  2004年   469篇
  2003年   414篇
  2002年   374篇
  2001年   319篇
  2000年   254篇
  1999年   233篇
  1998年   183篇
  1997年   165篇
  1996年   127篇
  1995年   139篇
  1994年   94篇
  1993年   78篇
  1992年   72篇
  1991年   63篇
  1990年   67篇
  1989年   65篇
  1988年   58篇
  1987年   26篇
  1986年   15篇
  1985年   22篇
  1984年   16篇
  1983年   20篇
  1982年   14篇
  1980年   9篇
  1979年   8篇
  1966年   6篇
  1964年   6篇
  1959年   7篇
  1958年   5篇
  1955年   7篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
In this paper we report our early experience with the design of technology for senior citizens. We take as our point of departure a pre-study of the ways in which older adult living occurs at three different senior housing facilities in southern Sweden. We contribute to the current debate concerning the ways in which digital technology can be designed to enable new types of living arrangements for the ever growing population of older people. We focus on technology designed to support the social rather than physical challenges of growing older. In particular we discuss how designing for social interaction can circumvent the stigma associated with being lonely in light of diminishing social networks, changed patterns of interactions with family, moving to a new neighbourhood, and the loss of a spouse. We will suggest that designers, in the design of digital technology for social interaction, deliberately leave room for ambiguity to make it possible for people to leave their intentions of use unarticulated. Furthermore, recognizing that many everyday activities already act as enablers for social interaction, we suggest utilizing such activities as an approach for design. We will support our suggestions by introducing three perspectives: a perspective emphasizing that the population of older adults is one of resourceful individuals; a perspective on social interaction emphasizing its circumstantial nature as an inherent part of everyday activities; and a perspective on the role of digital technology emphasizing its role as merely one of many resources present for human action. Finally, we will present an example concept showing how an enhanced TV remote control may be designed to enable social interactions without inflicting too much on the original experience of watching TV and most importantly, without stigmatizing the people using the remote control as lonely individuals craving the company of others.  相似文献   
992.
The European Cognitive Vision project VAMPIRE uses mobile AR-kits to interact with a visual active memory for teaching and retrieval purposes. This paper describes concept and technical realization of the used mobile AR-kits and discusses interactive learning and retrieval in office environments, and the active memory infrastructure. The focus is on 3D interaction for pointing in a scene coordinate system. This is achieved by 3D augmented pointing, which combines inside-out tracking for head pose recovery and 3D stereo human–computer interaction. Experimental evaluation shows that the accuracy of this 3D cursor is within a few centimeters, which is sufficient to point at an object in an office. Finally, an application of the cursor in VAMPIRE is presented, where in addition to the mobile system, at least one stationary active camera is used to obtain different views of an object. There are many potential applications, for example an improved view-based object recognition.  相似文献   
993.
In this paper, we present an approach for recognizing pointing gestures in the context of human–robot interaction. In order to obtain input features for gesture recognition, we perform visual tracking of head, hands and head orientation. Given the images provided by a calibrated stereo camera, color and disparity information are integrated into a multi-hypothesis tracking framework in order to find the 3D-positions of the respective body parts. Based on the hands’ motion, an HMM-based classifier is trained to detect pointing gestures. We show experimentally that the gesture recognition performance can be improved significantly by using information about head orientation as an additional feature. Our system aims at applications in the field of human–robot interaction, where it is important to do run-on recognition in real-time, to allow for robot egomotion and not to rely on manual initialization.  相似文献   
994.
Community computing has recently grown to become a major research area in human–computer interaction. One of the objectives of community computing is to support computer supported cooperative work among distributed collaborators working toward shared professional goals in online communities of practice. A core issue in designing and developing community computing infrastructures – the underlying socio-technical layer that supports communitarian activities – is sustainability. Many community computing initiatives fail because the underlying infrastructure does not meet end user requirements; the community is unable to maintain a critical mass of users consistently over time; it generates insufficient social capital to support significant contributions by members of the community; or, as typically happens with funded initiatives, financial and human capital resource become unavailable to further maintain the infrastructure. Based on more than nine years of design experience with Tapped In – an online community of practice for education professionals – we present a case study that discusses four design interventions that have sustained the Tapped In infrastructure and its community to date. These interventions represent broader design strategies for developing online environments for professional communities of practice.  相似文献   
995.
The world is inherently meaningful for us, i.e. we perceive the world in terms of what we can do with it, and by physically interacting with it we access this meaning and express the meaning. We believe that this is the core reason and foundation for turning to movement-based interaction. ‘Interaction creates meaning’ does not only hold for users during interaction but also for designers when generating ideas and developing concepts. Therefore, we postulate that if one truly likes to design for movement-based interaction, one has to be or become an expert in movement, not just theoretically, by imagination or on paper, but by doing and experiencing while designing. In order to do so, we believe that designers need design tools, techniques, knowledge, awareness and skills that support their search for expressive, rich behaviour. Our search for this support resulted in several methods, tools and knowledge that help designers exploring, visualising and reflecting on interactions. Our developed methods and tools such as the Design Movement approach with its choreography of interaction, gestural design tools, interactive installations and interactive tangible sketching, have not only supported and inspired designers to design for movement-based interaction, but also resulted in surprising, fresh designs in comparison with the limited scope of rather uniform and traditional electronic consumer products. This paper discusses the possibilities and limitations of our approach.  相似文献   
996.
水电厂房内的多场耦合振动分析是工程界十分关心的问题.为了实现发电厂安全生产的目标,过去在对其进行共振校核时,往往只对结构进行模态分析,而忽略了流体的存在;但是厂房流道内存在着大量的流体,流体的存在改变了厂房结构的动力特性,是属于典型的流固耦合振动问题.因此,在对其进行共振校核时应该考虑流体的影响.由于机理的复杂性、建模、数值模拟的困难性,迄今为止关于这方面的分析研究成果很少.本文借助于2个实际工程,对厂房结构与流体复杂的耦合振动问题进行分析,并对其进行比较,详细的阐述了厂房结构-流体的耦合振动特点.本文的研究成果对于解决流体-结构相互作用问题具有重要的工程意义,同时对于解决其他类型的流固耦合振动问题也具有很高的参考价值.  相似文献   
997.
计算机游戏界面设计中的人机交互性研究   总被引:1,自引:0,他引:1  
从计算机游戏界面的概念入手,阐述了游戏界面设计中交互性的概念、组成、作用及意义;通过软件界面和硬件界面,重点论述了游戏界面交互性设计的规律和原则,归纳提出了游戏界面设计中人机交互性的特殊要求。  相似文献   
998.
GUI(Graphical User Interface)是一种结合计算机科学、美学、心理学、行为学,及各商业领域需求分析的人机系统工程,强调人-机-环境三者作为一个系统进行总体设计。这种面向客户的系统工程设计其目的是优化产品的性能,使操作更人性化,减轻使用者的认知负担,使其更适合用户的操作需求,直接提升产品的市场竞争力。手机游戏的GUI包含了游戏的互动操作和视觉效果,文中就详细讨论了游戏的互动操作和视觉效果的各种规范要求,对颜色、图形、文字等画面风格规范要求,使软件界面的总体风格接近和类似系统界面的总体色调。  相似文献   
999.
本文旨在探讨计算机技术与传统数学教学的优化整合模式,研究如何充分利用现代教育资源,构思、设计出符合学生认知水平的计算机辅助教学,以达到充分调动学生学习积极性、提高高等数学课教学质量的目的。  相似文献   
1000.
La2/3 Sr1/3 Mn1-x ZnxO3films (x =0.05, 0.1,0.3, and 0.5) were prepared using magnetron sputtering method, and the effect of Zn doping on transport properties of the films was studied. An analysis of X-ray diffraction showed that the main phase of the bulk target was orthorhombic and the films had better epitaxial character. It was found that the films with x =0.05 and x =0.1 exhibited typical insulator-metal transition. No transition of the films with x≥0.3 was observed and the dominant transport was variable-range hopping due to observable secondary phase ZnO. These could be attributed to the Zn doping effect on manganites.  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