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Incentives to innovate are a central element of innovation theory. In the private-investment model, innovators privately fund innovation and then use intellectual property protection mechanisms to appropriate returns from these investments. In the collective-action model, public subsidy funds public goods innovations, characterized by non-rivalry and non-exclusivity in using these innovations. Recently, these models have been compounded in the private-collective innovation model where innovators privately fund public goods innovations. Private-collective innovation is illustrated in the case of open source software development. This paper contributes to the work on this model by investigating incentives that motivate innovators to share their knowledge in an initial situation, before there is a community to support the innovation process. We use game theory to predict knowledge sharing behavior in private-collective innovation, and test these predictions in a laboratory setting. The results show that knowledge sharing is a coordination game with multiple equilibria, reflecting the fragility of knowledge sharing between innovators with conflicting interests. The experimental results demonstrate important asymmetries in the fragility of knowledge sharing and, in some situations, more knowledge sharing than theoretically predicted. A behavioral analysis suggests that knowledge sharing in private-collective innovation is not only affected by material incentives, but also by social preferences such as fairness. The results offer general insights into the relationship between incentives and knowledge sharing and contribute to a better understanding of the initiation of private-collective innovation.  相似文献   
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This paper asks two - relatively simple - questions: can cities shape socio-technical transitions? And how would we know if they were? There are three key objectives. The first of these is to set out emerging, and in our view, convincing evidence, that large world cities have political aspirations to develop purposive and managed change in the socio-technical organisation of infrastructure networks that can be characterised as ‘systemic’ transitions. The second objective is conceptual in orientation and seeks to address how we understand transitions at the scale of the city, the role of ‘the city’ in undertaking transitions, and review both the strengths and shortcomings of the multi-level perspective (MLP) on socio-technical transitions in addressing this. The third objective is to identify what an urban transition would look like, and then constructs a new framework to conceptualise and research urban transitions. The paper then summarises the key aspects and implications of our argument.  相似文献   
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Anthropometric dimensions of male powerlifters of varying body mass   总被引:1,自引:1,他引:0  
In this study, we examined the anthropometric dimensions of powerlifters across various body mass (competitive bodyweight) categories. Fifty-four male Oceania competitive powerlifters (9 lightweight, 30 middleweight, and 15 heavyweight) were recruited from one international and two national powerlifting competitions held in New Zealand. Powerlifters were assessed for 37 anthropometric dimensions by ISAK (International Society for the Advancement of Kinanthropometry) level II and III accredited anthropometrists. The powerlifters were highly mesomorphic and had large girths and bony breadths, both in absolute units and when expressed as Z(p)-scores compared through the Phantom (Ross & Wilson, 1974). These anthropometric characteristics were more pronounced in heavyweights, who were significantly heavier, had greater muscle and fat mass, were more endo-mesomorphic, and had larger girths and bony breadths than the lighter lifters. Although middleweight and heavyweight lifters typically had longer segment lengths than the lightweights, all three groups had similar Zp-scores for the segment lengths, indicating similar segment length proportions. While population comparisons would be required to identify any connection between specific anthropometric dimensions that confer a competitive advantage to the expression of maximal strength, anthropometric profiling may prove useful for talent identification and for the assessment of training progression in powerlifting.  相似文献   
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The need for administrative know-how in libraries is great. Problems of administration in libraries do not differ significantly from those in other types of organizations. It behooves librarians to be aware of modern management theory, as developed and tested in the environment of business, and to adopt such useful tools as operations analysis and the systems approach to problems in the library environment.  相似文献   
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