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31.
Abstract The purpose of this study is to provide a preliminary framework to observe, analyse and evaluate both activity and learning in virtual communities. So various types of virtual communities will be studied by examining their relationship to socialisation and learning. After a presentation of the main ideas of Wenger's social learning theory, the principal components of the social context of the emergence and evolution of virtual communities will be described. It will show how taking this context into account enables the definition of four principal types of virtual communities: community of interest, goal-oriented community of interest, learners' community and community of practice and describe how the activity of these communities develops according to the goals they set for themselves and to the strategies they adopt to reach them. For each type of virtual community, an attempt will be made to determine the process of negotiation of meaning at the base of learning, and to describe the learning performed in terms of participation and reification processes. 相似文献
32.
Abstract The paper presents the main design issues of a distance learning course on Business on the Internet. The instructional design is based on a learner-centred instructional strategy which allows learners to construct their own knowledge while solving real business problems and transferring their knowledge to other learners. They learn autonomously taking the responsibility for their learning and following their individual cognitive styles, interests, preferences. The learners have access to the Internet being members of a global, cooperative learning community. The learning community involves students and tutors who collectively take responsibility for the design and evaluation of the course content and the teaching methods to be applied. Both students and tutors inhabit a virtual learning environment that offers different virtual places and services: virtual university, virtual enterprise, auditoriums, workshop rooms, cafes, libraries, etc. where students from different locations can meet, interact, learn and work together, as if they were face-to-face. 相似文献
33.
厘清关系确保大学城健康发展 总被引:2,自引:0,他引:2
我国高等教育的跨跃式发展,催生了大学城。大学城既是社会现象,又是一种全新的大学组织制度。文章认为要确保大学城健康发展,必须厘清大学城中大学与大学、大学与企业、大学与社区、大学与政府等诸方面的关系。 相似文献
34.
以徐州市黄河故道应用基因工程菌修复富营养化水体为研究对象,对水体中富营养化指标进行了测定,并对水体中生物生长变化情况进行了观察,试验和分析了基因工程菌中的消氮细菌及沉淀细菌对水体进行生物修复的作用及其效果,指出了存在的问题,为利用生物修复技术处理天然湖泊的富营养化提供了参考数据. 相似文献
35.
The article addresses the issue of learning to elearn in borderless programs in a globalised learning landscape and the associated problems of scaffolding the journey across the digital divide. The authors argue that the assumption underlying such courses is that cross-cultural programs are viable because they are conceived and designed to be ‘global’, and that they assume this design to be inclusive. Henning and Van der Westhuizen claim that the global discourse in most domains can take only marginal note of the need to infuse such programs with a local semiotic—a course design criterion for which they argue. They furthermore forward the notion that the majority of the world's prospective elearners need various bridging mechanisms in order to be able to access the broader discourse and that one of these mechanisms can be explored through the metaphor of “information ecologies” as proposed by Nardi and O'Day [Nardi, B.A., & O'Day, V.L. (1999). Information ecologies. Using technology with heart. Cambridge, MA: The MIT Press]. They also conclude that issues of the learners’ trust in the course and its system need to be considered when contemplating programs for diverse target groups. By way of a case study, consisting of three portraitures of adult learners, they explore the limitations of assumed distributed cognition and claim that learning is, in reality, contained/constrained in the familiar local narrative of the novice adult elearners in a rural South African context. The case study illustrates how the resistance to technology and its power base becomes an obstacle for the students and how the support of peers becomes the main scaffolding mechanism for their entry into electronic learning environments. The findings thus show how the social context becomes the facilitator and the scaffold for elearning, more than technology and the curriculum itself. 相似文献
36.
《Behaviour & Information Technology》2012,31(2):115-126
Three studies were conducted to ascertain how quickly people form an opinion about web page visual appeal. In the first study, participants twice rated the visual appeal of web homepages presented for 500 ms each. The second study replicated the first, but participants also rated each web page on seven specific design dimensions. Visual appeal was found to be closely related to most of these. Study 3 again replicated the 500 ms condition as well as adding a 50 ms condition using the same stimuli to determine whether the first impression may be interpreted as a 'mere exposure effect' (Zajonc 1980). Throughout, visual appeal ratings were highly correlated from one phase to the next as were the correlations between the 50 ms and 500 ms conditions. Thus, visual appeal can be assessed within 50 ms, suggesting that web designers have about 50 ms to make a good first impression. 相似文献
37.
Factors contributing to development of active communities are identified and combined into the Community Activity framework, which is useful in setting up new, or revitalizing inactive, communities. Found factors include: notifying members of new messages by e-mail, having a news section, and ability to add pictures to member profiles. During application of the framework to an inactive community, changes have been made to privacy options, polls, activity notifications, and other areas. Significant positive effects have been found in the number of visits, volume of posted messages, and number of topics. Interest of community members in both user profiles and the message board increased significantly. We conclude that the Community Activity framework is able to contribute in developing active online communities. 相似文献
38.
Immigrant homeowners’ function within ethnic boundaries in the housing market may have helped or hindered them during the recent U.S. Great Recession. This research explores this theme through interviews with immigrant and non-immigrant homeowners from four ethnic communities in Los Angeles County and the non-profit organizations that tried to assist them. Immigrant homeowners turned to co-ethnics for advice and support and formed multigenerational households as a strategy to achieve and sustain homeownership. Language and cultural barriers primed them for risky loans and thwarted their pursuit of refinance and modification when they struggled to make mortgage payments. These findings conform to existing evidence of ethnic segmentation in the housing market and imply that analyses of home buying and homeownership in areas with significant immigrant populations should factor in the role of ethnicity. 相似文献
39.
《Food Control》2014
As a traditional alcoholic beverage, Chinese rice wine is quite popular for its unique flavor and high nutritional value. In this study, we investigated the changes of flavor compounds in varying stages of fermentation by HS-SPME-GC-MS and HPLC. In addition, 16s rDNA-PCR was utilized to analyze the changes of bacterial communities during fermentation of Chinese rice wine from the Shaoxing region. It was noted that the content of flavor compounds including esters, higher alcohols, amino acids and organic acids was different in varying stages of fermentation. In general, the flavor compounds of Chinese rice wine were mainly produced after pre-fermentation. The results also showed that the bacterial community structures and diversity of Chinese rice wine varied significantly during different fermentation stages, and more than 10 genera of bacteria was detected in Chinese rice wine fermentation broth. Among these specific bacteria identified in the study, Lactobacillus (the predominant genus) and Bacillus might take an active part in flavor development in Chinese rice wine. This implied that these bacteria might play significant contributions on the flavor of Chinese rice wine. 相似文献
40.
Online newspapers (and other spaces) are increasingly seeking to utilise user-generated content alongside professionally developed material. However, this might leave websites increasingly vulnerable to trolls, who work to disrupt online communications in online spaces. Such behaviour can have serious consequences both in peoples online and offline lives, and for the development of coherent online communities. One means of controlling is through the manipulation of the online space to create social norms of polite behaviour through the founding of ‘imagined communities’ online.Approaching the issue from a discursive psychological perspective, this paper draws upon comments published in two online British newspaper comment sections responding to the publication of an academic article on trolling. Imagined communities are shown to arise irrespective of the presence of the virtual infrastructure to support the development of these imagined communities.Key features of imagined communities identified here are: individuation (as opposed to deindividuation); mutual influence between posters; shared history for both the users and the online space; the use of humour to cement social bonds. Analysis also revealed tensions in posters understanding of online and offline behaviours.This research holds implications for understanding online spaces, and the interactions between users within these spaces. 相似文献