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1.
赵文明  张敏 《科技通报》2014,(5):95-101
物联网服务的建模和验证是物联网研究中的重要问题。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I/O混成自动机。文中提出了基于时空I/O混成自动机的物联网服务建模与验证框架。在框架中,首先对物联网服务进行了描述,并使用时空I/O混成自动机对物联网服务进行建模。这些时空I/O混成自动机形成一个网络,刻画完整的物联网服务的通信并行过程。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对验证的物联网服务性质进行规约,最后使用定理证明器KeYmaera验证物联网服务的正确性。  相似文献   

2.
基于本体的多Agent的自动协商模型研究   总被引:2,自引:0,他引:2  
为解决电子商务中多Agent自动协商的难题,提出了基于本体的多Agent自动协商模型.首先介绍了该模型及其系统框架的结构,详细分析了多Agent自动协商过程,基于Agent自学习能力各协商状态能自动转换:提出了各类服务的本体描述,在语义层次上对各类服务活动进行描述、查询与自动匹配;为了支持多Agent之间的合作,综合考虑服务多属性,提出了一种多Agent间的柔性协商的方法,Agent通过对各类属性的协商,解决了供需双方间自动匹配问题.最后,从查全率、查准率两个指标验证了模型在判定供应商归属的有效性,通过对多属性的柔性协商验证了选定具体供应商的可行性.  相似文献   

3.
于华帅  刘惠艳 《内江科技》2014,35(10):14-15
动态分段技术是交通地理信息系统中一项重要的线性要素动态显示与分析技术,鉴于地下管网与路网具有一定的相似性,本文研究地下管线管理中的时空动态分段模型。近年来,学者对动态分段技术、时态地理信息系统以及时态数据库进行了大量研究,但缺乏支持管线信息显示的较完善的时空动态分段模型。本文首先分析了动态分段模型的研究现状,提出了一种适合管网应用的时空动态分段模型,在概念模型中,将动态分段系统的组成要素融入时态因素,并将属性的时态信息作为独立的属性信息存储,进而通过时态地理信息系统技术完成管线物理段的时态变化;利用统一建模语言(UML)的类图设计方式开发了物理模型,描述了时空动态分段模型中对象之间的关系,并定义了必要的属性和操作;借鉴线性参照系统(LRS)表达空间实体的方法,概括了模型中所涉及到的主要拓扑关系;最后通过实例验证了本文提出方法的有效性。  相似文献   

4.
目前在使用UML给软件系统建模时,针对用户界面建模很少或根本没有,这是因为UML缺少这方面的表达机制。基于此提出了使用UML扩展机制描述需求阶段GUI的用户界面需求表示方法,从而使得用户界面的需求分析描述更加直观和准确。同时,UML Profile将UML扩展到用户界面建模,丰富了UML的应用范围,使得对用户界面需求建模可以统一在UML语言和UML的建模工具中。  相似文献   

5.
本文基于技术接受与使用整合模型(UTAUT)理论,结合相关最新的研究成果,对原始UTAUT模型进行适当的修正,在原有变量的基础上添加信息性动机、娱乐性动机和个体创新性三个新变量作为核心变量,来探讨手机视频APP用户使用意愿影响因素,并进行实证研究。通过问卷调查搜集数据,利用结构化方程建模(SEM)方法进行假设验证。研究结果表明,努力期望、娱乐性动机与个体创新性是影响用户采纳手机视频APP的关键因素。  相似文献   

6.
采用模型检测方法验证微内核操作系统的进程间通信机制,提出了一种从源码提取验证模型的方法.该方法以L4操作系统的进程间通信机制的C++源码实现为检验对象,从源码实现直接提取形式化模型,得到Promela语言的模型描述,可以直接应用模型检测器Spin对其进行正确性检测.实验表明了该方法的可行性和实用性.  相似文献   

7.
采用统一建模语言UML进行系统建模的过程中,模型一致性的建立和维护是正确建模的必要前提。在UML模型的基础上对模型一致性问题进行了分析,给出了一致性问题的分类及模型一致性产生的原因。在此基础上进行模型一致性研究,并提出了关于模型一致性问题的解决方案和思路。  相似文献   

8.
分析当前舆情建模研究现状,提出比较符合社会实际的人际关系网络模型,并对建立该网络模型的思路,网络节点的类型、属性和关系进行描述。在此基础上,根据不同节点类型设定了相应的舆情演化规则,建立了基于人际关系网络的舆情演化模型。  相似文献   

9.
魏来  王雪莲 《现代情报》2010,30(8):19-24
WSMO作为W3C的成员报告,为语义网络服务提供了一个建模本体。文章全面系统的介绍WSMO的整体理论框架,包括理论模型(WSMO)、建模语言(WSML)和执行环境(WSMX)的构建,在此基础上,对WSMO和OWL-S两种描述网络服务的本体语言进行比较分析,并深入剖析了应用范例VTA。  相似文献   

10.
田浩 《大众科技》2011,(1):54-56
文章研究了基于C语言的GPS基带处理芯片验证环境的设计,对芯片验证理论进行了简要介绍,对传统时域滑动捕获算法和基于FFT的并行频域捕获算法进行了介绍,并对FFT的并行频域捕获算法的详细实现过程进行了描述。跟踪部分采用超前—滞后跟踪环对C/A码进行跟踪,采用科斯塔斯环对载波进行跟踪。使用MATLAB对设计进行了验证。  相似文献   

11.
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.
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.
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.
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.
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.
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 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.
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.
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   

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