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991.
The provision of online public goods: Examining social structure in an electronic network of practice 总被引:3,自引:0,他引:3
Electronic networks of practice are computer-mediated social spaces where individuals working on similar problems self-organize to help each other and share knowledge, advice, and perspectives about their occupational practice or common interests. These interactions occur through message postings to produce an on-line public good of knowledge, where all participants in the network can then access this knowledge, regardless of their active participation in the network. Using theories and concepts of collective action and public goods, five hypotheses are developed regarding the structural and social characteristics that support the online provision and maintenance of knowledge in an electronic network of practice. Using social network analysis, we examine the structure of message contributions that produce and sustain the public good. We then combine the results from network analysis with survey results to examine the underlying pattern of exchange, the role of the critical mass, the quality of the ties sustaining participation, the heterogeneity of resources and interests of participants, and changes in membership that impact the structural characteristics of the network. Our results suggest that the electronic network of practice chosen for this study is sustained through generalized exchange, is supported by a critical mass of active members, and that members develop strong ties with the community as a whole rather than develop interpersonal relationships. Knowledge contribution is significantly related to an individual's tenure in the occupation, expertise, availability of local resources and a desire to enhance one's reputation, and those in the critical mass are primarily responsible for creating and sustaining the public good of knowledge. Finally, we find that this structure of generalized exchange is stable over time although there is a high proportion of member churn in the network. 相似文献
992.
Mobile TV service, which provides television-like content through a mobile device, holds a limelight as the next killer application of wireless technologies and also as a prospective hedonic information technology. However, in a world where other potential wireless technologies and services speedily emerge, vendors and service providers interested in mobile TV hope that it will be diffused over the gulf between early users to general ones prior to competing sprouts. At this point, an investigation of early consumers’ adoption of mobile TV may offer precious information for its survival. Based on the theoretical assumptions of the technology acceptance model (TAM), this study examines influences of cognitive concentration (or flow experience) and media content on consumers’ acceptance of mobile TV. The results are threefold. First, results suggest that cognitive concentration (or flow experience) and content have a significant role in consumers’ intention to use hedonic information technology. Second, results show that content has a critical impact on cognitive concentration. Finally, results support the use of the extended TAM as an explainer in the context of hedonic information technology. 相似文献
993.
在含Cache的处理器中,代码排布和指令预取是减少取指延迟的常用技术.代码排布侧重研究代码执行的空间相对位置,指令预取则关注于代码执行的时间相对关系.片上Trace技术非入侵地获得程序的执行路径及时间信息,将代码执行的时空关系联系起来,因此为排布技术和预取技术的结合使用提供了基础.基于YHFT-DSP平台,利用程序运行的周期行为特性设置预取,利用VLIW结构处理器的空闲单元执行预取指令,提出以增加预取容限为目标的函数级代码排布方法.实验结果表明,该方法能有效预取并减少指令Cache失效. 相似文献
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