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81.
Pigeons were trained to match-to-sample with several new methodologies: a large number of stimuli, computer-drawn color picture stimuli, responses monitored by a computer touch screen, stimuli presented horizontally from the floor, and grain reinforcement delivered onto the picture stimuli. Following acquisition, matching-to-sample concept learning was assessed by transfer to novel stimuli on the first exposure to pairs of novel stimuli. One group (trial-unique), trained with 152 different pictures presented once daily, showed excellent transfer (80% correct). Transfer and baseline performances were equivalent, indicating that the matching-to-sample concept had been learned. A second group (2-stimulus), trained with only two different pictures, showed no evidence of transfer. These results are discussed in terms of the effect of numbers of exemplars on previous failures to find concept learning in pigeons, and the implications of the positive finding from this experiment on abstract concept learning and evolutionary cognitive development.  相似文献   
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Policy makers take initiatives to stimulate knowledge ecosystems in technology hotspots. It is implicitly assumed that these ecosystems will lead to value networks through which the participating companies can realize a competitive advantage. Value networks refer to business ecosystems where the value proposition is offered by a group of companies which are mutually complementary. The strategy literature suggests that business ecosystems lead to competitive advantages for each of the partners in the ecosystem. Based on a unique hand-collected database of 138 innovative start-ups in the region of Flanders, we analyze the knowledge and business ecosystem and the financial support network. We find that the knowledge ecosystem is well structured and concentrated around a number of central actors while the business ecosystem is almost non-existent at the local level. Further, we find that the financial support network is almost 100% publicly backed and fails to bridge the knowledge and business ecosystem. The implications for policy makers who tend to focus on the development of local ecosystems are discussed.  相似文献   
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The Family Service Units is a national charity working in some of the most deprived areas of the country. This paper is concerned with one part of its work, The Connections Project. This project aims to develop non-punitive anti-bullying partnerships between young people, schools, adults in the community and other agencies. This article focuses on a particular aspect of this project, the Support Code, which seeks to promote an ethos of proactive mutual support. The development is described and the teachers' reactions are explored. Though this work is currently being undertaken in primary schools, much is applicable to the early years of secondary education too.  相似文献   
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This article describes how the National Science Foundation's support of information research has evolved from NSF's original mission of improving the dissemination of scientific and technical information to its present interest in information robotics and intelligent systems. The pattern of grant support, since a major reorganization of the information science division in 1978, is analyzed in terms of the institutions, the investigators, and the disciplines that have been major grant recipients.  相似文献   
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