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921.
The main objective of this paper is to demonstrate the feasibility of Internet‐based real‐time control. A novel client/server‐based architecture for Internet‐based supervisory control with a Common Gateway Interface/Hyper Text Markup Language (CGI/HTML) interface is presented. A real‐time operating environment was established for closed‐loop control over Ethernet. We conceived of an autoregressive (AR) prediction scheme and a novel compensation algorithm to compensate for network‐induced time delays and data‐packet losses simultaneously. We constructed an open‐loop unstable ball magnetic‐levitation (maglev) setup as a test bed to validate the two proposed control architectures. Experimental results proved the feasibility of Internet‐based real‐time control and verified the effectiveness of the proposed time‐delay/packet‐loss compensation algorithm in networked feedback control systems. 相似文献
922.
One of the undisputed roles of the Internet is information spreading. However, to this day there is little understanding of the interaction between the way in which information is provided on the Internet and the behavior of different human personality types. This article focuses on the impact of the need for cognition on the desired level of interactivity of a given Website and on web surfing in general. For this experiment, four commercialized Websites were used: (1) flat with no hyperlinks and no time pressure; (2) flat with time pressure; (3) interactive1 with no time pressure; and (4) interactive with time pressure. All of the Websites contained identical information presented in different ways. The relations between need for cognition as a personality variable, time pressure as a situational stressor, the interactivity of the Web site, and several demographic variables were examined on Internet users’ behavior while surfing and on their preferences. One hundred and eighty-two experienced Web surfers took part in the experiment and were randomly assigned to one of the Websites. The number of hyperlinks used while surfing were counted by specially designed software. After surfing, the participants completed questionnaires regarding their satisfaction from the site, their willingness to return to the site, how persuasive the site was, and demographic data. It was predicted that people with high need for cognition would be more experienced in the Internet, use more hyperlinks, and stay longer in the site. People with a low need for cognition were predicted to prefer interactive over linear sites. Results support the preferences of people low in need for cognition of an interactive site. Other predictions were supported only partially. Implementations for Website design and further research are discussed. 相似文献
923.
互联网已经成为现代社会最重要的信息基础设施之一,越来越深刻地影响着人类的生活方式.基于互联网的通信产业链,已经开始向媒体、商务、金融等领域渗透和延伸.互联网产业的快速发展带来的机遇,对于电信运营商而言却更多地体现为一种挑战.本文在总结当前互联网产业特征和发展趋势的基础上,提出了如何应对互联网下一步发展趋势的策略和措施. 相似文献
924.
针对能源互联网中的海量分布式设备和电动汽车的需求,利用C#和Java编程语言设计并开发面向能源互联网的能量管理系统。该系统采用典型B/S 架构,以Asp.Net动态网页开发技术和数据库技术为核心,由云端后台算法、云端服务器的MySQL数据库、前端的网页三大部分构成。详细介绍了软件平台的系统框架,分为上下两层。其中,上层为日前-实时协同的多时间尺度能量管理系统模块,下层包含分布式设备协调控制子系统和电动汽车协调控制子系统。最后,通过仿真算例分析,能量管理系统能对海量的分布式设备和电动汽车进行优化调度,验证了该软件的可移植性、有效性和实用性。 相似文献
925.
926.
移动互联时代“互联网+产品质量追溯”管理体系建立初探 总被引:1,自引:0,他引:1
本文分析了移动互联时代“互联网+产品质量追溯”管理体系建立的必要性,介绍了互联网+产品质量追溯管理体系构成,存在的问题和需要解决的关键技术。文章最后提出了应加强部门协调和相关配套标准体系建设等具体建议。 相似文献
927.
互联网体系结构的演进已经成为学术界和工业界的共识,面向现有体系结构存在问题的修补策略以及基于各种思路的新的体系结构方案不断被提出,但得到大众认可并得到应用的少之又少.如何评估这些策略和方案是否符合互联网体系结构发展的需求成为当前急需解决的一个重要问题.现有的评估工作大多从用户或者ISP的效益出发对互联网体系结构的竞争力和演化趋势进行评估,它们并不考虑应用类型变化对互联网体系结构发展的影响.文中从应用的角度出发,立足于体系结构本身,提出了一种面向应用适应能力的体系结构评估方法,并构建了相应的评估模型2ACT(Application Adaptation CapaciTy),该方法以体系结构的服务适应性(Service AdapTability)及经济适应性(Economic AdapTability)为基础进行建模,以量化应用数据类型变化、应用部署开销对互联网体系结构发展的影响.该方法不但可用于评估体系结构自身的发展趋势,也可用于对体系结构中各种协议或机制的发展能力进行评估.针对当前多媒体数据流量剧增的现象,文中对两种适于多媒体数据应用的机制(In-network内容缓存机制和IP组播协议)进行了评估,结果发现这两种理论上具有优势的协议需在一定的限制条件下部署才能发挥其优势.用户或ISP可以结合自身的应用需求,根据2ACT模型的评估结果,选择相应的体系结构或者协议进行部署. 相似文献
928.
929.
Contemporary concerns that the Internet might lead to political apathy are based on suggestions that people would use the Internet for entertainment purposes rather than news consumption. However, what if someone stumbles upon news when surfing the Internet? Would this incidental news exposure online be helpful in promoting citizens’ political engagement? This study tests whether and how incidental news exposure (INE) and relative entertainment use (REU) on the Internet are associated with political participation. Drawing from US national data, results revealed a significant and positive relationship between INE and offline and online political participation while REU was negatively associated with offline and online political participation. More importantly, the role of INE in facilitating citizens’ online political participation was stronger for those who consume less entertainment online, indicating that incidental news exposure may increase existing gaps in political participation between people who prefer news and people who prefer entertainment online. 相似文献
930.
Electronic harassment and cyberbullying can take various forms and involve a range of perpetrators. This study utilised survey results from 1673 New Zealand students aged 12–19 years to explore electronic harassment on the internet and mobile phones and the distress associated with it. Overall, a third of participants reported electronic harassment in the prior year, with half (53.7%) rating it as distressing. Specific hypotheses and findings were that: mobile phone harassment would be more common and distressing than internet harassment, this was supported with 7% more participants reporting mobile phone harassment and 5.5% more reporting distress from it compared to internet harassment; females would report more harassment than males, this was supported for mobile phone harassment as females’ odds of harassment was approximately twice that of males (however the hypothesis did not hold for internet harassment); females would report more distress from harassment, this was supported for both internet and mobile phone harassment, with females’ odds of distress approximately twice as high as males; that some forms and perpetrators would be associated with more distress than others, again this was supported with the most distressing form of mobile phone harassment being direct verbal aggression and for harassment on the internet being rumour spreading. The study also found a preponderance of harassment from school peers. As predicted there were multiple interactions between the harassment forms and perpetrators and gender. These results highlight important differences in how harassment is delivered and experienced across the mobile phone and internet modalities. The findings point to the need to explicitly consider mobile phone harassment, as well as better ways to tailor interventions to address distressing harassment. Schools are well placed to address electronic harassment alongside other bullying interventions. 相似文献