基于Petri网的微博网络信息传播模型

微博网络中的信息传播模型是分析用户行为,找出传播路径,确定领袖人物,发现舆情热点等研究的基础。虽然多种不同角度的信息传播模型已经得到广泛研究,但缺乏对信息动态传播过程的直观描述。本文基于Petri网的结构和特征,针对微博网络信息传播过程,提出了一种简单直观的描述模型,该模型首先对微博网络的信息动态传播过程中的对象进行结构化描述。本文根据微博网络的用户结构关系,并利用Petri网的相关理论,形式化解释和定义信息传播基本对象,从而更加直接描述了微博网络中的转发、评论、回复等多种用户行为。在此基础上,本文利用Petri网能够描述信息流动问题的特征,结合颜色Petri网和时延Petri网,从Petri网系统的角度表示信息动态传播路径,并研究网络的动态性质和传播条件,使得信息传播模型更加真实地模拟信息传播情况。最后本文分析信息传播算例和新浪微博真实数据实验,验证了模型的有效性和可行性,为舆情态势分析以及用户行为的研究提供帮助和支持,同时也为其它社交网络信息传播的用户行为描述提供了新的思路。     

Strategies and cues adolescents use to assess the age of an online stranger

A common risk among adolescents is sexual solicitation, in which an adolescent is asked to provide sexual information, engage in sexual talk, or in sexual activities. Although scholars increasingly address this topic from an intrapersonal perspective, there is little attention to factors of language use and message content. In two focus group studies, we investigated whether adolescent girls consider themselves capable of assessing whether an online stranger is an adult or a peer, the extent to which adolescent girls actually succeed in making this assessment, the strategies they apply to do so, and the content- and language-related cues focused on. Our findings suggest that most of the adolescent girls are confident in their ability to assess whether the stranger is a peer or an adult with possible sexual intentions. However, we also found that only 43% were able to correctly make this assessment. Most of the adolescents seem to apply the passive strategy of uncertainty reduction: They scan the profile page of the stranger, check contact information, and the profile picture. They may choose to apply the interactive strategy to find out more about the online stranger. Important content-related cues that alarm adolescent girls are: ignoring personal questions, showing an exaggerated amount of interest, acting as a friend, and being sexually oriented. Language cues mentioned related to word usage, abbreviations, sentence length, and tone.     

Comparing Social Work Students’ Perceptions of Risk Using Online Discussion Fora: Lessons Learned from a European Pilot Project

Comparisons of international child welfare systems have identified two basic orientations to practice; a ‘child protection’ orientation and a ‘child welfare’ orientation, which are founded upon fundamentally different values and assumptions regarding the family, the origins of childcare problems, and the proper role of the state in relation to the family. This paper describes a project which sought to compare how undergraduate social work students from three European Universities perceive risk in referrals about the welfare of children and to explore the impact of different cultural, ideological and educational contexts on the way in which risk is constructed by students. Students from Northern Ireland, Germany and Poland examined three vignettes via 10 online discussion fora each of which provided a narrative summary of their discussion. The paper presents some findings from the analysis of the qualitative data emerging from the student discussions and draws out the lessons learned in terms of how the project was designed and implemented using online discussion fora.     

Observational practice in virtual worlds: revisiting and expanding the methodological discussion

Virtual worlds, such as World of Warcraft and Second Life, have seen remarkable mainstream uptake in the last decade. Such environments have grown from hosting niche interest groups to providing sites for leisure, business and education for tens of millions of Internet users. Concurrently, a multi-disciplinary research field exploring the application of such spaces has emerged. This article examines in detail one data collection practice – observation in virtual worlds – that has been applied extensively, but without extensive methodological discussion. By revisiting and extending earlier work on this topic, the article presents four key considerations for those conducting observational research in virtual worlds: defining and delimiting field sites, discerning attention, charting actions and attributing intention. It is concluded that researchers must both ward against flawed assumptions about virtual world observation and consider multi-method strategies to overcome limitations in observational data.     

Network domains in social networking sites: expectations,meanings, and social capital

This paper examines why the use of social networking sites (SNSs) leads to different results in cultivating bridging and bonding social capital for different groups of people. Based on in-depth interviews of 45 university students in Hong Kong, I find that Mainland Chinese students studying in Hong Kong actively use SNSs for seeking practical information about offline matters, and they obtain substantial enacted support from other Mainland students of the same university through SNS use. As a result, they accumulate both bridging and bonding social capital. Local Hong Kong students, however, use SNSs mainly for social information seeking and are only able to accrue limited bridging social capital through SNS use. Drawing on the theory of network domains, I argue that the different offline network structures in which students are located – namely, homogeneous and closed networks versus heterogeneous and open networks – explain this difference. Students with closed offline networks have defined expectations of online ties; they think of their online activities as practical and leading to real changes in their status among peers. Those with open networks have indefinite expectations of their online audience; thus, they interpret online activities differently, thinking of them as recreational, and they are playful in their online behaviour. These different outcomes of online activities consequently lead to diverse results in social capital accrual.     

Lurking Behavior in Online Psychosocial Discussion Forums: Theoretical Perspectives and Implications for Practice

Improving outcomes of telebehavioral psychoeducation requires rethinking program design when delivered wholly or partially for self-directed participation. Discussion forum participation often follows the “90-9-1 Rule” where 90% of participants lurk, rather than contribute content. A theoretical perspective on the behavior can help explain its adaptive functions, as well as the threats that this behavior poses to the lurker. Implications for practice require program redesign that actively links individual skills training and group-based discussion. The proposed linking design can synergize individual and group participation to support the development of mutual aid, as well as greater interaction with psychoeducation content and materials.     

网络小说接受的程式化现象

艺术接受程式化是指受众倾向于按照既有的心理模式或思维定势接受作品,受众的接受动机主要为消遣、娱乐,接受状态比较被动,接受效果主要为表层愉悦。当下网络小说接受的程式化现象主要表现为三个方面,即内容选择类型化、关注热点快速更替和接受视角单一化。网络小说接受的程式化现象是由复杂的社会条件和受众固有的接受心理决定的,有其存在的正当性与合理性,但其对艺术的负面效应也不应忽视。     

网络集群的自组织特征 —— 以“南京梧桐树事件”的微博维权为个案

近年来,伴随着急剧的社会结构转型,我国新的社会身份和社会认同群体也随之产生,在网络中的政治表达和利益维护活动增多,在这些网络讨论的集群内部,参与者会自发形成一定的秩序,推动事件的进行。本研究利用自组织理论作为分析框架,选取"南京梧桐树事件"的微博维权集群为研究对象,重点考察网络集群参与者之间从无序到有序的互动过程、整个系统的演变规律及其与外界的互动机制,由此总结出网络集群中的自组织特征,从而相对准确地把握虚拟社区系统的发展、演化阶段,为更好地理解互联网的社会功能起到借鉴作用,也为政府有关部门做好群体事件的预防工作提供理论和策略上的支持。     

从沃尔玛看传统零售商的电子商务发展转型

作为传统零售商的典型,沃尔玛较早地开展了电子商务的实践探索,在长期的发展中形成了极为宝贵的经验。从介绍沃尔玛的发展概况入手,分析了沃尔玛电子商务的发展背景、主要策略以及借鉴意义,在此基础上讨论了我国传统零售商发展电子商务的策略部署,并重点对传统零售商的电子商务平台的构建与管理做了探讨。加快电子商务的发展已成为传统零售商发展转型的重要选择。     

论网上政府采购安全的法律保障

网上政府采购在我国各地已展开,但其安全性引人瞩目.目前国内法律法规并未对网上政府采购安全予以充分的重视.网上政府采购所涉的安全问题甚为复杂,这源于该采购模式所具有的高技术性、无纸化、瞬时性等特点.完善网上政府采购立法是解决网上政府采购安全保障的必由之路.