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141.
Although there is a considerable amount of empirical evidence on inter-firm collaborations within technology-based industries, there are only a few works focussing on R&D cooperation by low-tech firms, especially small and medium-sized enterprises (SMEs). Providing further and new evidence based on a recently built database of CRAFT projects, this study analyses the relationship between technology and proximity in international R&D networks using HOMALS and statistical cluster techniques. The resulting typology of international cooperative R&D projects highlights that successful international cooperative R&D projects are both culturally/geographically closer and distant. Moreover, and quite interestingly, geographically distant projects are technologically more advanced whereas those located near each other are essentially low-tech. Such evidence is likely to reflect the tacit-codified knowledge debate boosted recently by the information and communication technology (ICT) “revolution” emphasized by the prophets of the “Death of Distance” and the “End of Geography”.  相似文献   
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This paper presents the results of a microscopic analysis conducted on supposedly retouched glass fragments that were likely used as tools. The pieces were recovered in a series of excavations performed at the historical site of Fortlet Miñana (1860–1869), a military settlement used during the war against the Indians on the southern border of Buenos Aires province, Argentina. The use of glass as raw material in archaeological sites of the historic period has frequently been reported in the Pampas and Patagonian regions. In this paper we present a review of ethnohistoric and ethnographic sources concerning the use of glass side scrapers, end scrapers, and arrowheads by aboriginal groups throughout the world. In order to perform the analysis, the glass fragments from Fortlet Miñana were compared to a series of experimental pieces on which traces of deliberate use on two kinds of raw material, wood and hide, were identified. The experimental approach and the microscopic analysis demonstrate that the retouched glass fragments recovered at Fortlet Miñana were not used as tools. Therefore, we conclude that microscopic analysis is of significant use to all researchers working with materials of this kind.  相似文献   
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Different economic theories suggest that residential and labor market relocations are mutually related. This has been verified in various empirical studies. We analyze this relationship based on a bivariate duration model of residential and labor market mobility. This specification is motivated by a search model that allows for simultaneous search on the labor and housing market, taking commuting costs into account. We investigate this relationship by using information on job and residence durations. In order to be able to analyze properly empirical duration data, we derive the statistical distributions of interest. Our empirical results based on a Dutch sample of full-time employed workers show that residential and labor market mobility depend positively on one another, which is in line with the theoretical search model presented. Moreover, we present easy-to-interpret measures for this dependency.  相似文献   
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