面向航天型号软件的需求管理研究

依据军用软件研制能力成熟度模型(GJB5000A)过程域,将航天型号软件的需求管理过程分为5个实践,重新定义结合敏捷方法的这5个实践,给出基于GJB5000A的航天型号软件敏捷需求管理活动流程图。将需求管理活动流程看作一种工作流,引入Petri网技术建立需求管理活动模型,并通过Petri网可达树和可覆盖树分析方法对建立的模型进行初步分析。最后将定义的需求管理过程实际运用到项目中,证明其科学性和可行性。     

敏捷软件开发过程模型研究

本文介绍了敏捷开发方法的价值观和基本原理,并从需求分析和开发周期两个方面对敏捷软件开发进行剖析,讨论敏捷软件开发如何对待软件的需求和设计,并调整XP编程实践,建立了敏捷软件开发过程模型.     

GJB 5000A模型的软件测量与分析过程探析

对GJB 5000A-2008军用软件研制能力成熟度模型中软件测量与分析过程的目的与要求进行了分析,明确软件测量与分析的目的——开发和保持测量能力,以支持管理信息的需要。并根据实践积累,对软件测量与分析过程的组织管理提出了解决方案。     

基于知识元和有色Petri网的应急实施流程优化方法

合理的应急实施流程对于有效应对突发事件至关重要。在知识元理论与Petri网方法的基础上提出了一种突发事件应急实施流程的优化方法。首先,借鉴共性知识模型,形式化表示活动基元及其内部联系,建立活动基元模型。随后,找到活动基元模型与有色Petri网的映射关系,并使用有色Petri网方法实现活动基元模型以及活动基元间的基本路由关系。在此基础上,结合知识元原理和Petri网方法,提出突发事件应急实施流程的五步优化方法。最后,以化学危险品事故为例说明该优化方法的使用过程。     

基于Petri网的协同工作流描述方法及建模

工作流技术作为实现企业协同的有效手段,广泛应用于各种场合,应用中的关键是建立适合企业过程的协同工作流模型.Petri网是一种适合于描述异步并发现象的系统模型,它既有严格的数学定义,又有直观的图形表示.文章主要介绍了Petri网和协同工作流模型的理论,以及基于Petri网的工作流建模方法,并给出了设计实例.     

运用敏捷思想改进软件测评流程

为了提高软件测试工程化水平,总装备部颁布了G JB2725 A标准,但在实践中发现基于该标准的软件测评过程工作程序相对繁琐,不能很好地与目前流行的敏捷开发思想进行融合。分析了基于GJB2725A标准的软件测评过程,结合敏捷开发思想,对软件测评过程进行了改进。研究发现,该方法在保证测试覆盖率和软件测试质量的同时,简化了工作流程,提高了工作效率。     

航天型号软件配置管理系统研究

通过对CMM（能力成熟度模型,Capability Maturity Model）中软件配置管理的研究,结合航天型号软件实时性、高可靠性和重用性的特点,提出使用B／S软件架构实现基于web技术的航天型号软件配置管理系统。传统的配置管理系统对航天软件生产实践缺少针对性,航天型号软件配置管理系统根据航天软件工程的实际需求,细化了软件配置项,提高了软件质量,实现了成熟软件模块的高重用性。介绍了CMM中配置管理的基本概念,完成了航天配置管理系统的概要设计,并对系统中配置项管理模块的实现思路进行了具体说明,最后时航天软件配置管理系统的应用前景进行了展望。     

PPQA在军用软件开发中的实施

过程与产品质量保证(PPQA)是GJB5000A军用软件研制能力成熟度模型中一个重要的关键过程域,在对该模型深入理解的基础上,分析了PpQA过程域所涉及的关键任务,并进一步说明在军用软件开发过程中如何有效的实施这些关键任务.     

基于敏捷思想的重量级IT项目管理框架思考

重量级IT项目具有高度复杂性和不确定性,以过程为基础的项目管理需要借敏捷方法加以改进.本文以阐明IT项目的复杂产品系统特性为起点,从复杂产品系统的模块化及分解入手,讨论了IT产品的动态形成过程,提出了一个基于敏捷开发过程的重量级IT项目管理框架.以提升重载方法开发效率、提高产品质量为目的,探讨了复杂产品分解的随机Petri网概念模型、柔性团队行为模型、重载方法适度规范集以及基于知识转移的敏捷开发过程,并提出了若干管理对策.     

面向对象petri网在系统建模中的应用

Petri网具有形象直观的图形描述和严格的数学定义,能描述异步、并发的系统模型.OO技术采用模块化设计思想和自底向上的设计方法,便于模型地设计和维护,有大事化小之功效.针对Petri网建模过程的结构复杂性,本文结合OO技术和Petri网实现了对一小型运货系统的建模,该方法较传统的Petri网建模更加灵活、高效.     

Low doses of a red wine ingredient figh diabetes in mice

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.     

To serve and promote science development via innovation

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.     

Students' Reactions to the Introduction of Videoconferencing for Classroom Instruction

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.     

Tracing the origin and early radiation of birds——Paleornithologist ZHOU Zhonghe

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."     

Cooler temperatures inductive to locust outbreaks

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.     

Exploring Multiplexity: Social Network Structures in a Computer-Supported Distance Learning Class

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.     

Molecular motor assembly of a biomimetic system

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.     

The Role of Intermediating Institutions in the Diffusion of Electronic Data Interchange (EDI): How Industry Associations Intervened in Denmark, Finland, and Hong Kong

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.     

How Electronic Publishers are Protecting Against Piracy: Doubts About Technical Systems of Protection

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.     

The Information Environment and Universal Service

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.