共查询到20条相似文献，搜索用时 46 毫秒
1.
为了描述信息物理融合系统(cyber-physical systems,CPS)的时空一致性,一种实时规范语言STe C已经提出[1],CPS的设计和实现能否满足时空一致性显得十分重要。文中对混成自动机进行了扩展,提出了具有位置驱动特点的时空自动机。文中提出了基于时空自动机的CPS建模与验证框架。在框架中,首先使用STe C语言对CPS进行了描述并使用时空自动机对CPS进行建模。文中采用的形式化验证方法为微分动态逻辑(differential dynamic logic,DL),其操作模型为HP(hybrid program)。利用DL可以将所建模型转换为对应的HP。结合得到的HP对验证的CPS属性进行规约,最后使用定理证明器Ke Ymaera对属性进行自动化验证。 相似文献
2.
3.
随着现代信息技术的不断发展,各地区供电信息通信技术也在不断提升,各县市之间也开始施行一体化运维方案,采取了"集中调控、分区运维"的模式,分别在市区和各管理分区内建立相应的调控站,进一步优化了运维管理的责任化和属地化,也提升了我国电力企业信息通讯管理工作的效率。本文即是对市县供电企业信息通信一体化运维模式进行研究,探讨了一体化运维模式的概念,并对信息通信一体化的建设方式进行说明,重点介绍了运维模式中监控体系的构建方式,最终阐述了运维模式建设过程中的优化方法,以期能为相关工作提供参考。 相似文献
4.
5.
浅谈新一代互联网信息资源管理模式--数字图书馆 总被引：5，自引：0，他引：5
计算机的日益普及，通信技术的不断完善，互联网的飞速发展，对图书馆传统服务模式提出挑战。而国际环境下的信息资源和用户信息需求与以往有着显著不同。因此，人们提出了新一代互联网信息资源管理模式——数字图书馆的设想。本文就数字图书馆的概念、特点以及建设的意义进行了阐述。 相似文献
6.
新兴信息通信技术的出现与发展不仅对商业领域产生了革命性影响,更给政府职能、管理模式带来了新的机遇和挑战。在新的信息通信技术条件下,各国政府相继出台各种政策与实施计划以大力推进电子治理。本文简要介绍了近年来新出现的Web2.0、移动技术、云计算等信息通信技术的概念及其技术特点;论述了新兴信息通信技术在各国电子治理中的实际应用和成果;探讨了这些新技术与政府治理相关的特征及其对政府的影响。 相似文献
7.
信息物理系统(Cyber Physical System,CPS)作为下一代智能感知系统,有效的将虚拟世界与物理世界进行融合,实现计算、通信、控制协同工作。CPS技术构成包括多方面,涉及军工、消防、交通、医疗等各大领域。由于CPS各节点间的数据传输存在规模性、动态性、异构性,选择一种合适的数据交换格式是提高系统传输效率的关键。目前数据间的交换多使用文本格式,针对XML、JSON的数据传输方式,其传输格式复杂,压缩文件体积较大,效率较低;相比较,Google推出的Protocol Buffer二进制传输格式在传输时效方面更具优势。本文主要以异构网关中不同格式的数据转换性能为研究重点,通过不同传输格式传输时效性的对比,并采用具有优势的Protocol Buffer方式对CPS系统数据进行封解包。 相似文献
8.
赵凡 《科技成果管理与研究》2013,(7):10-11
量子计算与量子信息是一个多学科的交叉研究课题,同时也是各种不同形式研究的交叉,涉及量子力学、信息学、计算机科学、密码学、数学、物理学的多个分支,如凝聚态物理、原子分子物理、光学等。清华大学物理系核物理教研室主任龙桂鲁从1998年开始进行量子计算与量子信息的研究工作,在他看来,量子计算与量子信息的研究是一个潜在的高新技术研究,如果量子计算机一旦真正运用,那会带来一个新的时代。作为量子计算和量子通信领域的探路者,多年来,龙桂鲁在这一领域开拓创新,取得了许多令世界瞩目的研究成果。他领导团队提出首个量子安全直接通信方案,开辟和引导了该研究方向;提出首个多方高维密集编码模型,发展了分布式量子通信理论;提出了分步传输和块传输方法;建立了量子搜索相位匹配理论,在科学研究中做出了突出的贡献。 相似文献
9.
针对传统的CPS上层资源调度中,信道的选择具有一定的突发性和随机性,随着外界信息多样性、复杂性的不断增加,转换后的信息往往存在冲突.为此,本文提出了基于消息反馈的CPS上层资源动态分配与优化调度策略.把前期的CPS资源调度情况反馈给后续的调度程序,通过这种合理的动态调度信息反馈,实时反馈调度情况.实验结果表明,该方法能够较好地克服数据的冲突,调度效率有了明显地提高. 相似文献
10.
当前以信息化、自动化和互动化为特征的智能企业建设,对信息技术提出了更高的要求。针对当前信息通信技术企业桌面终端服务管理的特点和存在的问题,提出管理与技术并重的工作思路。结合广西博联信息通信技术有限责任公司实践经验,阐述提高桌面终端信息安全水平的具体管理措施和技术方法,以期提升企业IT运维的效率。 相似文献
11.
A research group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol-a chemical found in the skins of red grapes in red wine-can improve the sensitivity of mice to the hormone insulin according to a report in the October issue of Cell Metabolism.…… 《中国科学院院刊(英文版)》2008,22(1):14-15
Aresearch group led by Prof. ZHAI Qiwei from the Institute for Nutritional Sciences under the CAS Shanghai Institutes for Biological Sciences has discovered that even relatively low doses of resveratrol--a chemical found in the skins of red grapes and in red wine--can improve the sensitivity of mice to the hormone insulin, according to a report in the October,2007 issue of Cell Metabolism. As insulin resistance is often characterized as the most critical factor contributing to the development of Type 2 diabetes, the findings“provide a potential new therapeutic approach for preventing or treating” both conditions, the researchers said. 相似文献
12.
《中国科学院院刊(英文版)》2008,22(1):2-3
CAS should stick to the principle of rendering service to, and giving impetus for, the development of China＇s science enterprise by making S＆T innovations, said CAS President LU Yongxiang. The CAS president made the remarks in a recent talk to communicate the gist of the winter session of the Party＇s Leading-member Group at CAS, which was held from 7 to 11 January in Beijing. 相似文献
13.
Marjorie Armstrong-Stassen Margaret Landstrom Ramona Lumpkin 《The Information Society》1998,14(2):153-164
This study examined how students who had no prior experience with videoconferencing would react to the use of videoconferencing as an instructional medium. Students enrolled in seven different courses completed a questionnaire at the beginning of the semester and again at the end of the semester. Students at the origination and remote sites did not differ in their reactions toward videoconferencing but there was a significant difference for gender. Women reacted less favorably to videoconferencing. Compared to the beginning of the semester, students reported significantly less positive attitudes toward taking a course through videoconferencing at the end of the semester. There were no significant differences in students' attitudes toward videoconferencing across courses at the beginning of the semester but there were significant differences across the courses at the end of the semester. The results suggest the need for better preparation for both students and instructors. 相似文献
14.
《中国科学院院刊(英文版)》2008,22(1)
With great care, Dr. ZHOU Zhonghe takes out a package wrapped by cotton tissue from a drawer and says: "This is the gem of our collections: the fossil of a bird that lived 125 million years ago!" Then, pointing at a tiny mound, he explains: "Look, this is the claw and that is the head. It was in the egg shell and ready to hatch ... The species fell into a family of waterside inhabitants." 相似文献
15.
A joint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology his co-workers from Norway US Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells suggesting that China's projected climate warming could decrease the pest's numbers. The study was published in Proceedings of the National Academy of Sciences on September .…… 《中国科学院院刊(英文版)》2008,22(1):6-7
Ajoint study by Prof. ZHANG Zhibin from the CAS Institute of Zoology and his co-workers from Norway, US and Swiss have indicated that historical outbreaks of migratory locusts in China were associated with cold spells, suggesting that China＇s projected climate warming could decrease the pest＇s numbers. The study was published in Proceedings of theNational Academy of Sciences on 17 September, 2007. 相似文献
16.
Caroline Haythornthwaite 《The Information Society》2001,17(3):211-226
A computer-mediated group is a complex entity whose members exchange many types of information via multiple means of communication in pursuit of goals specific to their environment. Over time, they coordinate technical features of media with locally enacted use to achieve a viable working arrangement. To explore this complex interaction, a case study is presented of the social networks of interactions and media use among members of a class of computer-supported distance learners. Results show how group structures associated with project teams dominated who communicated with whom, about what, and via which media over the term, and how media came to occupy their own communication niches: Webboard for diffuse class-wide communication; Internet Relay Chat more to named others but still for general communication across the class; and e-mail primarily for intrateam communication. Face-to-face interaction, occurring only during a short on-campus session, appears to have had a catalytic effect on social and emotional exchanges. Results suggest the need to structure exchanges to balance class-wide sharing of ideas with subgroup interactions that facilitate project completion, and to provide media that support these two modes of interaction. 相似文献
17.
Active biological molecules functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery disease diagnosis therapy new nanodevice construction.…… 《中国科学院院刊(英文版)》2008,22(1):22-22
Active biological molecules and functional structures can be fabricated into a bio-mimetic system by using molecular assembly method. Such materials can be used for the drug delivery, disease diagnosis and therapy, and new nanodevice construction. 相似文献
18.
Electronic data interchange (EDI) provides means for interorganizational communication, creates network externalities, requires an advanced information technology (IT) infrastructure, and relies on standards. In the diffusion of such innovations, institutional involvement is imperative. Such institutions contain governmental agencies, national and global standardization organizations, local government, and nonprofit private organizations like industry associations. The last type of organizations we call intermediating institutions. They intermediate or coordinate ("inscribe") the activities of a group of would-be adopters. Unfortunately, little is known of how these organizations shape the EDI diffusion trajectory. In this article we examine one specific type of intermediating organizations?industry associations?and how they advanced the EDI diffusion process in the grocery sectors of Hong Kong, Denmark and Finland. We identify six institutional measures, placed into a matrix formed by the mode of involvement (influence vs. regulation) and the type of diffusion force (supply push vs. demand pull), that can be mobilized to further the EDI diffusion. Industry associations were found to be active users of all these measures to varying degrees. Their role was critical especially in knowledge building, knowledge deployment, and standard setting. Furthermore, institutional involvement varied due to policy and cultural contingencies and power dependencies. 相似文献
19.
Leah A. Lievrouw 《The Information Society》2000,16(2):155-159
This essay focuses on universal service and the Internet as means to support social and political participation. The emphasis on access to telecommunications systems in conventional approaches to universal service is contrasted with access to content. A model of the information environment is described that accounts for the roles of content and conduit, both of which are necessary conditions to achieve true access. A method is outlined for employing information indicators to observe or measure the information environment. 相似文献
20.
Puay Tang 《The Information Society》1998,14(1):19-31
The increasing prospects of digital piracy has prompted the perceived need by electronic publishers to adopt technical systems of protection, and governments to reform their copyright laws. This article is a preliminary study of the management of intellectual property by electronic publishers, defined as those involved in the production of online databases, and CD-ROMs. It focuses on three main issues: (1) how electronic publishers view the increasing threat of piracy; (2) the methods of protection employed to protect intellectual property in digital format; and (3) the importance of technological protection of intellectual property in electronic publications. The analysis is based on a sample of 23 UK electronic publishers. The interviews revealed an interesting assortment of protection methods and did not show that technological protection was a preferred way. Instead, the means of protection, in addition to copyright law, comprised niche markets, pricing, trust, bad publicity, and nontechnical and technical means. 相似文献