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This paper analyses the collaborative design ofa high-technology product, a neuromagnetometerused in the analysis of the activity of thehuman cortex. The producer, Neuromag Company istrying to transform the device from a basicresearch instrument into a means of clinicalpractice. This transition is analyzed as asimultaneous evolution of the product,producer-user network and user activities. Thenetwork is analyzed as a network of activitysystems. Each activity has a historicallyformed object and a motive of its own, as wellas a system of cultural means and expertise. Weuse these to explain and understand theinterests and points of view of the actors inrelation to the product and the contradictionsof the producer-user network. It is suggestedthat the emerging user needs of collectiveactors must be analyzed at three levels. At thefirst level, the use value of the product, itscapacity of solving the vital problems andchallenges of developing user activities, ischaracterized. The second-level analysisconcerns the creation and development of thenecessary complementary tools and services thatmake the implementation and use of the productpossible. This task presupposes collaborationbetween several communities of the innovationnetwork. The third level is the situatedpractical use of the product. In ourexperience, it is advantageous that researcherscontribute with their data to a dialogue inwhich the user needs are articulated. 相似文献
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Distributed Coordination and Workflow on the World Wide Web 总被引:5,自引:0,他引:5
Antonietta Grasso Jean-Luc Meunier Daniele Pagani Remo Pareschi 《Computer Supported Cooperative Work (CSCW)》1997,6(2-3):175-200
This paper describes WebFlow, an environment thatsupports distributed coordination services on theWorld Wide Web. WebFlow leverages the HTTP Webtransport protocol and consists of a number of toolsfor the development of applications that require thecoordination of multiple, distributed servers.Typical applications of WebFlow include distributeddocument workspaces, inter/intra-enterprise workflow,and electronic commerce. In this paper we describe thegeneral WebFlow architecture for distributedcoordination, and then focus on the environment fordistributed workflow. 相似文献
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Gijsbert Erkens Jeroen Janssen 《International Journal of Computer-Supported Collaborative Learning》2008,3(4):447-470
Although protocol analysis can be an important tool for researchers to investigate the process of collaboration and communication,
the use of this method of analysis can be time consuming. Hence, an automatic coding procedure for coding dialogue acts was
developed. This procedure helps to determine the communicative function of messages in online discussions by recognizing discourse
markers and cue phrases in the utterances. Five main communicative functions are distinguished: argumentative, responsive, informative, elicitative, and imperative. A total of 29 different dialogue acts are specified and recognized automatically in collaboration protocols. The reliability
of the automatic coding procedure was determined by comparing automatically coded dialogue acts to hand-coded dialogue acts
by a human rater. The validity of the automatic coding procedure was examined using three different types of analyses. First,
an examination of group differences was used (dialogue acts used by female versus male students). Ideally, the coding procedure
should be able to distinguish between groups who are likely to communicate differently. Second, to examine the validity of
the automatic coding procedure through examination of experimental intervention, the results of the automatic coding procedure
of students, with access to a tool that visualizes the degree of participation of each student, were compared to students
who did not have access to this tool. Finally, the validity of the automatic coding procedure of dialogue acts was examined
using correlation analyses. Results of the automatic coding procedure of dialogue acts of utterances (form) were related to
results of a manual coding procedure of the collaborative activities to which the utterances refer (content). The analyses
presented in this paper indicate promising results concerning the reliability and validity of the automatic coding procedure
for dialogue acts. However, limitations of the procedure were also found and discussed. 相似文献
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Jane Pitcher 《Urban Policy and Research》2006,24(1):67-82
This article explores the role of qualitative and collaborative methods when undertaking evaluation research into local community safety partnerships and neighbourhood strategies. It draws on recent examples of research and evaluation studies of regeneration and community safety programmes in a number of cities and towns in England. The discussion is set against the background of the major changes in policy relating to crime and community safety, particularly the introduction of Crime and Disorder Partnerships and their engagement with local communities. The value of qualitative methods in exploring some key questions is discussed, particularly within a collaborative approach to policy research. 相似文献
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针对区块链应用于物联网环境下的特点和要求,分析了目前广泛应用于联盟链的实用拜占庭容错算法(PBFT)的弊端以及目前应用于共识网络中的门限签名算法存在的普遍问题,提出改进的共识算法。首先,新共识机制将网络中的节点分组用部分节点的两两通信代替所有节点的两两通信减少通信量;其次,将组合公钥的思想引入到门限签名中,减少了通信量与计算量;最后,在节点之间引入信用分机制,优化视图切换协议。仿真结果表明,新提出的共识算法在数据吞吐量以及通信时延方面有了明显的提升,并且得到了通信量最低时的最佳分组方式。 相似文献