自媒体时代民间微公益现状及发展

自媒体时代下,以具参与性与公开性的微博为平台,民间微公益应运而生。民间微公益迅猛的发展得益于微博独特开放的传播特性,出现参与者众多的盛况,但同时,公益性信息管理的规范,草根大众对公益发起及运作的科学性,又成为民间微公益发展的重要掣肘。本文以免费午餐为个案,对其发展现状进行研究,并提出相关的解决对策。     

用于工业控制系统的无线网络通信MAC协议的研究

无线网络技术已被广泛的应用在工业控制系统中,介质访问控制(MAC)协议作为工业控制系统无线网络通信的底层基础,是保证无线网络高效通信的关键协议.针对搭载多收发器无线终端的工业控制系统设计了一种能源有效的MAC协议—MH-MAC,该协议可根据不同网络环境和应用的需求,灵活地配置信道分配方案和介质访问策略,采用MH-RS调度算法来协调多个收发器高效工作.最后与B-MAC协议进行了比较分析,实验表明MH-MAC协议在提高网络带宽、降低传输时延、增加网络吞吐量和减少能量消耗等方面明显优于B-MAC协议,具有良好的可扩展性和实际应用价值.     

新媒体背景下的传统媒体应对——基于媒体公信力的视角

媒体公信力是媒体生存的根基。新媒体技术的崛起从三个方面对传统媒体的公信力形成冲击：弱化了传统媒体的＂把关人＂角色、对传统媒体报道新闻的表现手段及消费方式形成冲击、对传统媒体的经营和管理手段提出新的挑战。在新媒体背景下传统媒体应发挥权威的鉴定者角色,打造透明新闻。面对公民新闻的压力,传统媒体应向受众赋权,加强对新媒体资源的整合、组织能力。媒体管理中还应融入更多自律手段,重塑媒体公信力。     

基于数据世系的微博信息管理与检索算法研究

在微博平台中用户的消息以流的形式按照时间顺序到达系统,对微博数据流的有效管理可以及时地响应用户的查询操作。基于数据库的数据世系思想,提出了一种基于数据世系的微博信息管理方法。首先,根据事件的产生、发展以及变化,将同一社会事件包含的消息定义为数据世系;其次,将微博消息流划分为不同的数据世系,并根据新消息动态地维护数据世系集合;最后,应用数据世系中的文本消息响应用户的查询。实验表明,基于数据世系的微博信息管理方法使用的内存少,运行效率高,可用于微博消息流的实时处理及查询响应工作。     

Driving a Wedge Between Evidence and Beliefs: How Online Ideological News Exposure Promotes Political Misperceptions

This article has 2 goals: to provide additional evidence that exposure to ideological online news media contributes to political misperceptions, and to test 3 forms this media‐effect might take. Analyses are based on representative survey data collected during the 2012 U.S. presidential election (N = 1,004). Panel data offer persuasive evidence that biased news site use promotes inaccurate beliefs, while cross‐sectional data provide insight into the nature of these effects. There is no evidence that exposure to ideological media reduces awareness of politically unfavorable evidence, though in some circumstances biased media do promote misunderstandings of it. The strongest and most consistent influence of ideological media exposure is to encourage inaccurate beliefs regardless of what consumers know of the evidence.     

Being a Serial Transnational Activist

Transnational activism endures as a political practice turning a mirror onto the world's powerbrokers. We analyse a variety of transnational activism best characterized as serial by virtue of an observed systematic time and border‐spanning commitment to protest communication. Following statistical disambiguation of a dataset of 2.5 million unique Twitter users, we identified a subset of exceptionally prolific communicators and interviewed 21 of them. We show that a noted prominence in networked communication of otherwise unremarkable Twitter users may be an upshot of purposive strategies intended to publicize, support or help orchestrate collective action. Accordingly, we propose the term “engagement compass” to address the relationship between activists' life‐patterns and their personal investment in protest over time.     

Urban Social Media Demographics: An Exploration of Twitter Use in Major American Cities

This article explores intersections between place, race/ethnicity, and gender amongst American Twitter users and makes an argument that studying the intensity of tweets provides insights into how and why particular groups tweet. Given recent events in American political life such as the shooting in Ferguson, Missouri and the reactions by young, urban African Americans on Twitter, understanding the role of race, place, gender, and age is important. We observed the time between tweets of urban American Twitter users and explored whether the medium may be providing traditionally marginalized groups, such as young Black men, with potential avenues for mobilizing communication and access to resources.     

Who creates Trends in Online Social Media: The Crowd or Opinion Leaders?

Internet slang words can very quickly become ubiquitous because of social memes and viral online content. Weibo, a Twitter‐like service in China, demonstrates that the adoption of popular Internet slang undergoes 2 distinct peaks in its temporal evolution, in which the former is relatively much lower than the latter. An in‐depth comparison of the diffusion of these different peaks suggests that popular attention in the early stage of propagation results in large‐scale coverage, while the participation of opinion leaders at the early stage only leads to minor popularity. Our empirical results question the conventional influentials hypothesis and provide some insights for marketing practice and influence maximization in social networks.     

Media Niche of Electronic Communication Channels in Friendship: A Meta‐Analysis

The current landscape of communication technologies is characterized by a wide variety of choices. As each medium provides different affordances, each may occupy a different niche and be used in different relationships. Drawing on the theory of the niche, we did a meta‐analysis involving 27 effect sizes from 22 independent samples to test the correlation between media selection/use and friendship closeness. Results showed that the 5 communication channels filled 2 different friendship closeness niches. Mobile phone calls and texting had stronger positive correlations with friendship closeness than instant messaging, social network sites, and online gaming. Culture, but not gender, moderated some of these correlations: Friendship closeness had a stronger positive association with SNS use and online gaming in collectivist cultures.     

The Double‐Edged Sword: The Effects of Journalists' Social Media Activities on Audience Perceptions of Journalists and Their News Products

As social media become popular news platforms, journalists and news organizations have been keen to capitalize on their potential to build and maintain audiences. However, little is known about the extent to which these efforts may have adverse implications. Based on normative theories, the present study investigates the influence of journalists' social media activities (specifically, self‐disclosure and interaction with other users) on audience perceptions of journalists. An experiment (N = 267) revealed that: Although both journalists' self‐disclosure and interaction positively influenced audience perceptions of the journalists in the personal dimension, interaction negatively influenced audience perceptions in the professional dimension; and the perceptions transferred to perceptions of news products, thereby mediating the relationship between journalists' social media activities and audience news perceptions.