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31.
The Gezi Protests, an environmental sit‐in that turned into a social movement in Turkey, is often compared to the Arab Spring and the Occupy movement with regard to the importance attributed to social media. This paper examines the role that social media played during the protests, with an emphasis on how trust was built and maintained among the protestors. In‐depth interviews with 21 active Gezi protestors revealed that social trust and system trust were intertwined in actual practices. On one side, technological affordances worked as an interface that facilitated social identification, which helped in trusting the person behind the information. On the other side, technological affordances themselves invited different levels of trust, subject to both physical constraints and technological barriers. 相似文献
32.
Evaluating the Wisdom of Strangers: The Perceived Credibility of Online Consumer Reviews on Yelp 下载免费PDF全文
This study examined the effects of review valence, the reviewer profile, and the receiver's familiarity with the platform (user/nonuser) on the perceived credibility of a review on Yelp.com and on the receiver's attitude toward the reviewed object. The results demonstrated a difference in cue‐taking between users and nonusers. For users, there was an interaction effect of 2 profile cues (number of friends and number of reviews) on competence. Users interpreted the cues in combination, whereas non‐users were not influenced by them. The friends × reviews × platform familiarity interaction indirectly affected attitude through competence. Further, review valence was positively associated with perceived credibility and attitude. The findings support and extend the social information processing theory and cue combination literature. 相似文献
33.
The Rise of Twitter in the Political Campaign: Searching for Intermedia Agenda‐Setting Effects in the Presidential Primary 下载免费PDF全文
Bethany A. Conway Kate Kenski Di Wang 《Journal of Computer-Mediated Communication》2015,20(4):363-380
Questions exist over the extent to which social media content may bypass, follow, or attract the attention of traditional media. This study sheds light on such dynamics by examining intermedia agenda‐setting effects among the Twitter feeds of the 2012 presidential primary candidates, Twitter feeds of the Republican and Democratic parties, and articles published in the nation's top newspapers. Daily issue frequencies within media were analyzed using time series analysis. A symbiotic relationship was found between agendas in Twitter posts and traditional news, with varying levels of intensity and differential time lags by issue. While traditional media follow candidates on certain topics, on others they are able to predict the political agenda on Twitter. 相似文献
34.
Underwater communication primarily utilizes propagation of acoustic waves in water. Its unique characteristics, including slow propagation speed and low data rates, pose many challenges to Media Access Control (MAC) protocol design. In most existing handshaking-based underwater MAC protocols, only an initiating sender can transmit data packets to its intended receiver after a channel reservation through a Request-to-Send (RTS)/Clear-to-Send (CTS) handshake. This conventional single-node transmission approach is particularly inefficient in underwater environments, as it does not account for long propagation delays. To improve channel utilization in high latency environments, we propose a novel approach that exploits the idle waiting time during a 2-way handshake to set up concurrent transmissions from multiple nodes. The sender can coordinate multiple first-hop neighbors (appenders) to use the current handshake opportunity to transmit (append) their data packets with partially overlapping transmission times. After the sender finishes transmitting its packets to its own receiver, it starts to receive incoming appended packets that arrive in a collision-free packet train. This not only reduces the amount of time spent on control signaling, but it also greatly improves packet exchange efficiency. Based on this idea, we propose an asynchronous, single-channel handshaking-based MAC protocol based on reverse opportunistic packet appending (ROPA). From extensive simulations (single- and multi-hop networks) and comparisons with several existing MAC protocols, including MACA-U, MACA-UPT, BiC-MAC, Slotted-FAMA, DACAP, unslotted Aloha, we show that ROPA significantly increases channel utilization and offers performance gains in throughput and delay while attaining a stable saturation throughput. 相似文献
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36.
由于多媒体编码和解码的问题.导致不能在线观看.只能下载到本地播放。本文采用了流媒体技术。通过设计WEB视频网站并以其为平台实现视频资源在线播放。本文说明了流媒体服务器的配置和如何使用ASP.NET工具设计设网站。 相似文献
37.
何志强 《电脑与微电子技术》2010,(11):103-106,112
阐述网络电台的发展现状及前景。结合校园广播电台的实际,在分析校园网络电台功能结构的基础上,提出校园网络电台的设计方案。利用PHP和MySQL搭建网络电台,详细介绍声音的采集、模拟信号的编码和广播的实现过程,进而对校园网络电台的搭建进行总结。 相似文献
38.
本文就远程教学中出现的流媒体技术做了简要说明,并对Windows Media软件中包含的3个组件进行了重点说明。对利用该组件进行课件采集、制作,Media服务器配置,Media Player功能等做了详细介绍,同时也描述了Windows Media的发展前景。 相似文献
39.
Travis Gagie 《Information Processing Letters》2008,108(6):418-421
Sorting is a classic problem and one to which many others reduce easily. In the streaming model, however, we are allowed only one pass over the input and sublinear memory, so in general we cannot sort. In this paper we show that, to determine the sorted order of a multiset s of size n containing σ?2 distinct elements using one pass and o(nlogσ) bits of memory, it is generally necessary and sufficient that its entropy H=o(logσ). Specifically, if s={s1,…,sn} and si1,…,sin is the stable sort of s, then we can compute i1,…,in in one pass using O((H+1)n) time and O(Hn) bits of memory, with a simple combination of classic techniques. On the other hand, in the worst case it takes that much memory to compute any sorted ordering of s in one pass. 相似文献
40.
Studies have demonstrated that students prefer PowerPoint and respond favorably to classes when it is used. Few studies have addressed the physical structure of PowerPoint. In this study, students enrolled in several psychology classes on two campuses completed a 36 item questionnaire regarding their preferences for the use of PowerPoint in the classroom. Students preferred the use of key phrase outlines, pictures and graphs, slides to be built line by line, sounds from popular media or that support the pictures or graphics on the slide, color backgrounds, and to have the lights dimmed. It is recommended that professors pay attention to the physical aspects of PowerPoint slides and handouts to further enhance students’ educational experience. 相似文献