Anatomy of Protest in the Digital Era: A Network Analysis of Twitter and Occupy Wall Street

Two months before the first Occupy Wall Street (OWS) protest in September 2011, activists were using Twitter to organize and spread the movement. In this study, the earliest Twitter messages regarding #OccupyWallStreet were subjected to network analysis to answer these questions: What were the central hubs in the OWS discourse on Twitter in the summer of 2011? How did OWS emerge from among several social movement organizations to lead a nationwide series of demonstrations? What were the key points in the Twitter dialogue that aided the process of scale shift? By addressing these questions, this research connects social movement concepts with network centrality measures to provide a clearer picture of movements in the digital era.     

Evolution of what? A network approach for the detection of evolutionary forces

Structures of evolving populations are traditionally derived from traits of its members. An alternative approach uses network metrics to define groups that evolve jointly. This supposes that selection acts not only on who members are (i.e., traits) but also on to whom they are connected (i.e., interdependent relationships). This paper presents a method to meaningfully quantify differences in evolutionary forces over multiple levels of population taxonomies and tests almost 1000 multilevel partitions of 8 empirical networked populations evolving over time. It shows that multilevel network metrics as selection criteria identifies stronger evolutionary natural selection than trait based population taxonomies.     

当代大学生网络道德建设刍议

随着互联网在大学校园的迅猛发展,网络对大学生的影响日益增大,网络道德失范问题在大学生中日渐凸现。但由于网络运行规律的独特性,对当代大学生网络道德建设问题可采取相应对策：即奠定网络道德建设的思想基础;营造网络道德建设的良好环境;健全网络道德建设的有效机制;规范网络道德建设的网上行为;造就网络道德建设的得力师资。     

网络环境下高校图书馆创新信息服务的思考

网络环境对高校图书馆信息服务工作提出了严峻挑战。本文分析了网络环境下高校图书馆信息服务工作面临的新特点,提出了创新信息服务工作的新思路。     

网络环境下的主机信息安全研究

随着计算机网络的高速发展和普及,主机信息安全变得日益重要。本文分析了网络嗅探的主要手段,包括共享式和交换式网络的嗅探,以及基于DNS欺骗的嗅探和对HTTPS的嗅探等,并给出了相应的对策。除了防止网络嗅探外,提出了针对个人主机的安全维护的具体措施,对保障网络金融安全具有重要意义。     

Why are some more peer than others? Evidence from a longitudinal study of social networks and individual academic performance

Studies of peer effects in educational settings confront two main problems. The first is the presence of endogenous sorting which confounds the effects of social influence and social selection on individual attainment. The second is how to account for the local network dependencies through which peer effects influence individual behavior. We empirically address these problems using longitudinal data on academic performance, friendship, and advice seeking relations among students in a full-time graduate academic program. We specify stochastic agent-based models that permit estimation of the interdependent contribution of social selection and social influence to individual performance. We report evidence of peer effects. Students tend to assimilate the average performance of their friends and of their advisors. At the same time, students attaining similar levels of academic performance are more likely to develop friendship and advice ties. Together, these results imply that processes of social influence and social selection are sub-components of a more general a co-evolutionary process linking network structure and individual behavior. We discuss possible points of contact between our findings and current research in the economics and sociology of education.     

Telecommunications Network Design—Comparison of Alternative Approaches

The design and development of the network infrastructure to support mission‐critical applications has become a critical and‐complex activity. This study explores the use of genetic algorithms (GA) for network design in the context of degree‐constrained minimal spanning tree (DCMST) problem; compares for small networks the performance of GA with a mathematical model that provides optimal solutions; and for larger networks, compares GA's performance with two heuristic methods—edge exchange and primal algorithm. Two performance measures, solution quality and computation time, are used for evaluation. The algorithms are evaluated on a wide variety of network sizes with both static and dynamic degree constraints on the network nodes. The results indicate that GA provides optimal solutions for small networks. For larger networks it provides better solution quality compared to edge exchange and primal method, but is worse than the two methods in computation time.     

基于网络层次分析的中国职业教育评价

运用网络层次分析法的理论与计算方法,从基本情况、经费情况和办学效益三个方面建立我国职业技术教育状况评价指标体系,在运用网络层次分析法全面考虑指标层次之间及层次内部相互关系的基础上确定指标体系的权重,是对层次分析法的有效改进。对我国部分省市的职业技术教育状况进行了实证分析与比较,给出了这些省市的职业技术教育状况排序及结果分析。     

产业集群的市场结构分析

产业集群网络由市场关系网络和社会关系网络复合而成.产业集群独特的网络结构使产业集群内部市场结构接近完全竞争,集群内部资源配置有效;产业集群外部市场结构接近完全垄断或寡头垄断,表现出强大的区域竞争力.     

城市地铁网络复杂性研究

城市地铁网络属于空间复杂网络,其中的节点与边对应于地理空间中的特定位置。文中首先应用Pajek与Ucinet分析了世界主要城市地铁网络的拓扑特性,发现它们拥有如下共性：倾向于选择短边、平均度数接近于2、聚集系数接近于0,直径较大。进而从网络连通性、特征路径长度与直径的变化趋势三方面分析了北京地铁网络的鲁棒性,研究发现北京地铁网络在节点随机故障情况下具有较好的鲁棒性,但在恶意攻击情况下整个网络很快就会瘫痪。