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61.
This article presents part of phase 2 of a research project funded by the NSF-National Science Digital Library Project, which observed how academic users interact with the ScienceDirect information retrieval system for simulated class-related assignments. The ultimate goal of the project is twofold: (1) to find ways to improve science and engineering students’ use of science e-journal systems; (2) to develop methods to measure user interaction behaviors. Process-tracing technique recorded participants’ processes and interaction behaviors that are measurable; think-aloud protocol captured participants’ affective and cognitive verbalizations; pre- and post-search questionnaires solicited demographic information, prior experience with the system, and comments. We explored possible relationships between affective feelings and cognitive behaviors. During search interactions both feelings and thoughts occurred frequently. Positive feelings were more common and were associated more often with thoughts about results. Negative feelings were associated more often with thoughts related to the system, search strategy, and task. Learning styles are also examined as a factor influencing behavior. Engineering graduate students with an assimilating learning style searched longer and paused less than those with a converging learning style. Further exploration of learning styles is suggested.  相似文献   
62.
In this article we propose that medical practice evolves as a result of progress along three different pathways: improvement in the ability to develop effective medical technologies, learning in medical practice, and advances in biomedical scientific understanding of disease. The relative importance of these three pathways varies from case to case, and often they interact strongly. More specifically, we argue here that in cases of therapeutic innovation where a new medical technology is involved the advance in medical practice is driven largely by the ability to develop and use effective medical artifacts and the interactive sequence among these interdependent pathways often starts with what is learned in practice and not in science. While we state this argument in general, we develop it in detail in a longitudinal and contextual case study of the emergence and evolution of a treatment for advanced heart failure based on an implantable device, the Left Ventricular Assist Device (LVAD). Our findings show that an essential aspect of the evolution of the LVAD therapy is collective and cumulative learning that requires experience that only can be gained through the actual use of LVADs. We discuss the theoretical and policy implications that follow from our understanding of how medical practice evolves for research on the evolution of medical practices and new medical technologies, and policies about the evaluation of rapidly moving medical practices and clinical research involved in their advancement.  相似文献   
63.
Charles Darwin hoped that a large body of working naturalists would embrace evolution after the Origin of Species appeared in late 1859. He was disappointed. His evolutionary ideas at first made painfully little progress in the scientific community. But by 1863 the tide had turned dramatically, and within five years evolution became scientific orthodoxy in Britain. The Origin's reception followed this peculiar trajectory because Darwin had not initially tied its theory to productive original scientific investigation, which left him vulnerable to charges of reckless speculation. The debate changed with his successful application of evolution to original problems, most notably orchid fertilization, the subject of a well-received book in 1862. Most of Darwin's colleagues found the argument of the Origin convincing when they realized that it functioned productively in the day-to-day work of science-and not before. The conceptual force of the Origin, however outwardly persuasive, acquired full scientific legitimacy only when placed "in the harness of daily labour".  相似文献   
64.
Collaboration in large-scale projects introduces challenges involving both coordination (the ability to collaborate) as well as cooperation (the willingness to do so). Existing research has shown how modular designs can improve coordination by locating interdependencies within rather than between different modules. Based on an in-depth case study of collaboration in a large-scale infrastructure project, our study highlights an effect of modularity on collaboration that previously has been overlooked. Specifically, we show that while modular designs may help overcome coordination challenges by reducing interdependencies between modules, they can in turn hamper collaboration by emphasizing specialization within modules. Therefore, though existing work typically perceives modularity and integration as opposites, we clarify how they can also act as complements. In particular, we show how firms need to complement modular designs with integrating practices that stimulate cooperation. Overall, we contribute to the literature on collaboration and modularity by explaining when and how organizations can combine modularity and integration.  相似文献   
65.
The scientific theme for the 2006 Bower Award for Achievement in Science was Electric Power Systems. The award was presented to Narain G. Hingorani for the conceptualization and pioneering advancement of Flexible AC Transmission Systems (FACTS) and Custom Power in electric power systems, and for outstanding technical contributions in High Voltage Direct Current (HVDC) technology. His contributions have enhanced the quality and security of the electric power system, and are expected to revolutionize future alternating current power transmission and distribution systems.  相似文献   
66.
There is an ongoing debate over the activities of brands and companies in social media. Some researchers believe social media provide a unique opportunity for brands to foster their relationships with customers, while others believe the contrary. Taking the perspective of the brand community building plus the brand trust and loyalty literatures, our goal is to show how brand communities based on social media influence elements of the customer centric model (i.e., the relationships among focal customer and brand, product, company, and other customers) and brand loyalty. A survey-based empirical study with 441 respondents was conducted. The results of structural equation modeling show that brand communities established on social media have positive effects on customer/product, customer/brand, customer/company and customer/other customers relationships, which in turn have positive effects on brand trust, and trust has positive effects on brand loyalty. We find that brand trust has a fully mediating role in converting the effects of enhanced relationships in brand community to brand loyalty. The implications for marketing practice and future research are discussed.  相似文献   
67.
68.
The web creates manyopportunities for encroachment on intellectualproperty including trademarks. Our principaltask in this paper is an investigation into anunusual form of such encroachment: theimproper use of metatags. A metatag is a pieceof HTML code that provides summary informationabout a web page. If used in an appropriatemanner, these metatags can play a legitimaterole in helping consumers locate information. But the ``keyword'' metatag is particularlysusceptible to manipulation. These tags can beeasily abused by web site creators anxious tobait search engines and bring scores ofvisitors to their sites. The law aboutmetatags is far from settled and many legalscholars are uncomfortable with the conclusionthat the unauthorized use of a trademark in ametatag represents infringement. How should weassess this practice known as ``spamdexing'' froma normative perspective? Is it commercial fairplay or something more sinister? We make thecase here that there are salient moral problemswith spamdexing since it exploits thereputational goodwill of trademark owners andconfuses consumers. It violates basic moralduties and it flouts the golden rule principle. Hence unauthorized use of a competitor'strademark in a metatag is not morallyacceptable.  相似文献   
69.
This paper considers the changing role of universities in the UK as they respond to an engagement agenda that stipulates a more immersive and visible interaction between academics and the public. It constitutes a survey of attitudes to public engagement in a selection of UK universities drawing on interviews with senior academics with managerial responsibility at the end of 2009. The results of this study reflect a mood of indecision and anxiety among respondents towards a public engagement agenda seen to influence the contours of their professional identities and working lives. The study situates academic accounts that contest the legitimacy of public engagement as a core academic activity and the role of academics in communicating with public groups. Moreover, it reveals a lack of agreement and consistency in the conceptualisation and application of public engagement in higher education contexts, certainly beyond an emergent discourse of research impact.  相似文献   
70.
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