基于RBAC的访问控制在信息系统中的应用

访问控制是管理信息系统经常采用的安全措施之一．对RBAC(基于角色的访问控制机制)的基本原理进行介绍,然后结合某档案管理信息系统的开发实例,介绍了RBAC在信息管理系统中的设计和应用．     

The effectiveness of post-16 pathways for gaining employment associated with undergraduate degree study

This article sets out to examine the effectiveness of five different post-16 study pathways and the impact that spending time away from education has on gaining employment associated with an undergraduate degree. It also explores advice and guidance for students looking at post-16 study options, higher education and employment. An initial online survey was used, followed by case studies to form a mixed-method approach. The findings suggest that a vocational pathway better prepares students for making decisions around employment and study in comparison to the more traditional A Level pathway. They also highlight that a period of one to four years after finishing post-16 study and starting undergraduate degree study is the most effective for students to gain employment associated with their undergraduate degree. Finally, it was found that most participants did not have positive experiences with advice and guidance regardless of their pathway.     

A Random Multi-Access Method for Data Services in CDMA Cellular System

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从高职入口看我国高等职业教育改革

我国现有高职入口模式“门槛高”、“面向窄”，不适应职业教育的发展方向。我们要改革高职入口模式，坚持以考查职业技能为主，面向全民，建立相关改革配套措施，推动全民职业素质的提高。     

Three dimensions of equity of access to higher education

Concerns over equity of access to higher education are widespread, but there is significant disagreement over what should constitute a fair system. This article assesses diverse conceptualisations of equity and explores the ways in which they embody themselves in the policies of three systems, those of England, Brazil and Kenya. While showing significant disparities of income level and enrolment ratio, all three have made concerted efforts to expand higher education access, accompanied by increasing stratification in terms of the quality and prestige of institutions. Analysis of policy options and outcomes leads to a proposal of three principles for understanding equity of access: availability, accessibility and horizontality. The third of these principles addresses the little-acknowledged safeguard that disadvantaged students should not be confined to lower-quality institutions, while at the same time allowing for diversity of ethos and disciplinary focus.     

基于无线通信的静止式进相器系统设计

静止式进相器是专为大中型绕线式电机节能降耗设计的无功功率就地补偿装置。现有静止式进相器仅停留在单台电动机和单台静止式进相器的配套使用上,缺乏监控系统、历史数据无法保存。详细介绍了基于无线通信的静止式进相器系统设计,系统由静止式进相器控制子系统和主控子系统组成,使用无线通信模块实现静止式进相器和主控机的通信。主控子系统设计中,采用预约ALOHA实现主控子系统的多址通信。该系统经过实验和现场调试,其结果表明:静止式进相器补偿效果明显,实现系统无线通信功能,满足无线监测的设计要求。     

New Media/Internet Research Topics of the Association of Internet Researchers

This study summarizes prior reviews of new media and Internet research, and the growth of the term Internet in academic publications and online newsgroups. It then uses semantic network analysis to summarize the interests and concepts of an interdisciplinary group of Internet researchers, as represented by session titles and paper titles and abstracts from the 2003 and 2004 Association of Internet Researchers conferences. In both years, the most frequent words appearing in the paper abstracts included Internet, online, community, social, technology, and research. The 2003 papers emphasized topics such as the social analysis/research of online/Internet communication, community, and information, with particular coverage of access, individuals, groups, digital media, culture; role and process in e-organizations; and world development. The 2004 papers emphasized topics such as access; news and social issues; the role of individuals in communities; user-based studies; usage data; and blogs, women, and search policy, among others.     

Gaps and Bits: Conceptualizing Measurements for Digital Divide/s

Three arguments are raised in this article with regard to the indices used to measure the digital divide. First, I criticize policymakers who rely on simplistic measures of the digital divide, at the expense of a thoughtful analysis of (1) the purpose of the tool, (2) the level of observation, and (3) the method of approaching the data. Second, I argue that networks and associated technologies are not neutral artifacts but are political and social spaces in their structure as well as in their content levels. Accordingly, we need to factor in the context as an important actor in conceptualizing and measuring the digital divide. Third, two general types of indices are used for the measurement of the digital divide(s): focused monotopical indices and comprehensive indices. Monotopical indices are more widely available, while comprehensive ones are rare. I argue that policymakers need to promote comprehensive indices over monotopical indices. Finally, I present a conceptual definition of the digital divide and a framework for developing a comprehensive index to measure it.     

国内两大开放存取系统的对比研究——奇迹文库和中国预印本服务系统

信息资源的共享对于学术工作者有着重要的意义，本文着重介绍了开放存取运动在中国的实践。深入探讨了中国的两大开放存取系统奇迹文库和中国预印本服务系统，对比两者异同，指出中国两大开放存取系统的优势与尚待完善之处。     

E-prints预印本数据库的自组织同行评议模式设计

经历21世纪前十年快速发展后,OA期刊与预印本数据库发展遭遇瓶颈,最主要原因是OA期刊与预印本数据库至今未能构建一套评议效度不低于传统同行评议模式、适应开放存取环境的新型同行评议模式。本文提出一种预印本数据库环境下,不需要传统编辑介入与期刊载体、由预印本系统按照客观规则与算法推动同行评议活动持续进行、"人人评我、我评人人"的自组织同行评议模式。将自组织同行评议模式与现有代表性同行评议模式进行了比较。预印本数据库下的自组织同行评议模式能够很大程度上消除传统同行评议模式以及我国学术出版与学术评价中存在的诸多弊端,具有范式变革的理论价值以及为构建我国国家级预印本数据库提供决策参考的实践价值。