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   5791篇
  免费   275篇
  国内免费   304篇
电工技术   72篇
技术理论   1篇
综合类   168篇
化学工业   37篇
金属工艺   83篇
机械仪表   186篇
建筑科学   90篇
矿业工程   40篇
能源动力   28篇
轻工业   18篇
水利工程   14篇
石油天然气   6篇
武器工业   44篇
无线电   1589篇
一般工业技术   184篇
冶金工业   13篇
原子能技术   16篇
自动化技术   3781篇
  2024年   2篇
  2023年   41篇
  2022年   68篇
  2021年   110篇
  2020年   117篇
  2019年   67篇
  2018年   97篇
  2017年   161篇
  2016年   187篇
  2015年   190篇
  2014年   355篇
  2013年   295篇
  2012年   333篇
  2011年   418篇
  2010年   301篇
  2009年   347篇
  2008年   407篇
  2007年   445篇
  2006年   460篇
  2005年   395篇
  2004年   331篇
  2003年   332篇
  2002年   246篇
  2001年   162篇
  2000年   135篇
  1999年   113篇
  1998年   62篇
  1997年   49篇
  1996年   31篇
  1995年   36篇
  1994年   22篇
  1993年   17篇
  1992年   9篇
  1991年   11篇
  1990年   1篇
  1989年   9篇
  1988年   3篇
  1987年   1篇
  1984年   2篇
  1983年   1篇
  1979年   1篇
排序方式: 共有6370条查询结果,搜索用时 46 毫秒
61.

Background

The use of surveys is becoming popular in the health care industry for acquiring information useful to the accomplishment of several studies. Besides their exploitation on a large scale for conducting epidemiological studies, surveys are being increasingly carried out on a narrower perspective through the administration of questionnaires aimed at assessing the quality of life perceived by patients or their clinical status during mid- or long-term treatments. This is useful for managing resources or optimizing and individualizing treatments.

Objectives

This paper describes Gquest, a platform for modeling, generating and administering questionnaires through mobile devices such as smartphones or tablets. Gquest was motivated by the need of administering questionnaires during home treatments, albeit its applicability is rather general. The main requirement was to have a very simple, clean and easy to use platform able to support (a) physicians in the design and delivery of questionnaires and (b) outpatients in sending self-recorded outcomes to the clinical staff.

Methods

Gquest has two basic components. The first one is a model devised for representing questionnaires which is extremely flexible. It allows the generation of questions and answers of different types, supports adaptivity in the dialog with the user and enforces simple consistency rules for checking his input. The second component is an application able to run instances of those questionnaires. It downloads questionnaires over the air in terms of XML files from a server and stores them locally into the mobile repository. Questionnaires become then available to the user, who in our case is a patient or one of his relatives. The user can select which one to fill-in, according to his needs and/or the specific treatment protocol. The selected questionnaire may be filled-in all at once or be completed in subsequent steps over time since any input provided is persisted on a local database. Finally, when a questionnaire is closed all the answers are transparently synchronized to a server for further evaluation or statistical purposes.

Results

The platform has been exploited and tested in two medical domains where questionnaires have very different purposes; a quality of life pilot survey involving patients with atrial fibrillation within the EU-funded project MobiGuide, and an investigation of the users’ needs during the requirements elicitation phase of a telemedicine project for the safe discharge of fragile patients.

Conclusions

Gquest proved to be a suitable tool for dealing with a wide variety of question types and has been positively accepted by the patients enrolled in the pilot study.  相似文献   
62.
从手机银行的应用现状出发,阐述手机银行的技术架构以及常见的安全风险。结合国家等级保护及行业主管部门的相关技术要求,分析手机银行的各个层面的风险评估指标,并采取层次分析法确定各指标的权重,最后得出手机银行的总体安全情况。在此基础上形成的手机银行风险评价体系,可量化风险评估结果,为手机银行的风险管理提供依据。  相似文献   
63.
位置相关信息服务中访问数据涉及到复杂的空间计算,导致访问数据的延迟时间较长,而数据预取能够显著提高数据的访问速度,缩短访问数据的时间。基于LDD的预取策略如DDP考虑了数据距离,但是没有考虑数据的访问概率和更新频率及数据大小。针对以上问题提出基于价值的数据预取(CDP)策略,一些重要的数据预取因素如访问概率、更新频率、数据项大小、数据距离和有效范围等都包含在价值函数里,根据价值函数值的大小来选择被预取的数据。通过实验对比,CDP比DDP策略能更有效的提高缓存命中率。  相似文献   
64.
移动系统平台多样化以及各移动系统开发平台互不兼容,使移动应用开发周期长移植性差。为解决移动应用能够实现一次开发多处运行的问题,提出基于HTML5的移动应用跨平台解决方案。基于HTML5的跨移动平台特性,结合JavaScript、CSS等Web应用开发技术,实现iOS、Android两主流移动系统的跨平台开发,在移动管理驾驶舱系统中验证方案的可行性和实用性。该方案节省开发资源同时又满足移动应用的开发与销售模式。  相似文献   
65.
随着平板电脑、智能手机的普及,移动互联网时代已经到来。各种交互式媒体、移动应用对数字媒体专业人才培养提出新的挑战。在对常熟理工学院数字媒体技术专业建设分析的基础上,结合移动互联网时代未来的发展方向,提出优化课程体系、调整课程结构、重组课程内容、注重复合型人才培养的改革思路。  相似文献   
66.
随着科学技术的飞速发展,作为网络信息领导者的移动通信在日常生活工作中的应用也越来越广泛,但是移动通信在应用中也会遇到很多问题,比如移动网络切换延迟现象较为普遍,组播包的丢包率比较高等等.本文针对于以上问题,分析了多种组播协议,提出了新型的基于Agent的移动组播算法,此算法可以有效地改进切换延迟和丢包率等问题.  相似文献   
67.
随着移动互联网技术快速发展,图书馆事业迎来了前所未有的发展机遇。移动互联网涵盖面广、便捷性高、用户可以随时随地通过网络访问图书馆资源。普及移动图书馆服务,是我国目前图书馆事业的主要发展方向之一。本文简单介绍了互联网环境,从技术角度和系统建设两个方面阐述了这一主题。  相似文献   
68.
In this study, we explored how stereoscopic depth affects performance and user experience in a mobile device with an autostereoscopic touch display. Participants conducted a visual search task with an image gallery application on three layouts with different depth ranges. The task completion times were recorded, and the participants were asked to rate their experiences. The results revealed that the image search times were facilitated by a mild depth effect and that too great a depth slowed search times and decreased user-experience ratings.  相似文献   
69.
Situated Learning stresses the importance of the context in which learning takes place. It has been therefore frequently associated with informal learning or learning outside the classroom. Cloud technologies can play an important role supporting this type of learning, since it requires ubiquitous computing support, connectivity and access to data across various scenarios: on the field, in the classroom, at home, etc. In this paper we first present the situated learning theory and how we can take advantage of services offered by Cloud Computing to implement computer applications implementing learning activities based on this theory, providing pertinent geographical information and discussion boards. Next we propose a software architecture schema which can be used as a basis for integrating existing cloud services into new applications supporting learning activities. Then we present two examples developed with this approach with its viability and advantages. These are discussed in the concluding chapter.  相似文献   
70.
The last 2 decades have seen a constantly increasing interest in mindfulness, due to its positive effects on health and well-being. Recently, a number of mobile applications aimed at supporting people in practicing mindfulness techniques have appeared, but their efficacy has not been formally evaluated yet. In this paper, we first introduce the reader to mindfulness techniques, traditional as well as computer-based. Then, we propose and evaluate a mobile application (called AEON) aimed at helping users in practicing thought distancing, i.e. a mindfulness technique that requires one not to react in response to his/her thoughts but to be aware of them and observe them while they go away. AEON allows the user to enter his/her thoughts and visualize them as written in ink on a parchment placed under water. By touching the screen, the user can interact with the water and produce waves that progressively dissolve each written thought. We evaluate AEON on a sample of naive meditators (i.e. people with no or minimal experience with meditation), contrasting it with two traditional thought distancing techniques that are not computer-based. The first traditional technique requires users to mentally visualize their thoughts as printed on clouds and observe them as they pass by, while the second requires users to write their thoughts on cards, then pick up the cards one at a time, look at them and toss them into a wastepaper basket. AEON obtained better results in terms of achieved mindfulness, perceived level of difficulty and degree of pleasantness. Since practicing mindfulness tends to be difficult for naive meditators, these results suggest that AEON can be a novel and effective way to help them approach mindfulness.  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