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181.
Search patterns and absorptive capacity: Low- and high-technology sectors in European countries 总被引:4,自引:0,他引:4
Searching for externally available knowledge has been characterised as a vital part of the innovation process. Previous research has, however, almost exclusively focused on high-technology environments, largely ignoring the substantial low- and medium-technology sectors of modern economies. We argue that firms from low- and high-technology sectors differ in their search patterns and that these mediate the relationship between innovation inputs and outputs. Based on a sample of 4500 firms from 13 European countries, we find that search patterns in low-technology industries focus on market knowledge and that they differ from technology sourcing activities in high-technology industries. 相似文献
182.
The increasing commercialization of university discoveries has initiated a controversy on the impact for scientific research. It has been argued that an increasing orientation towards commercialization may have a negative impact on more fundamental research efforts in science. Several scholars have therefore analyzed the relationship between publication and patenting activity of university researchers, and most articles report positive correlations between patenting and publishing activities of scientists. However, previous studies do not account for heterogeneity of patenting activities. This paper explores the incidence of patenting and publishing of scientists distinguishing between corporate patents and patents assigned to non-profit organizations for a large sample of professors active in Germany. While patents assigned to non-profit organizations (incl. individual ownership of the professors themselves) complement publication quantity and quality, patents assigned to corporations are negatively related to quantity and quality of publication output. 相似文献
183.
Frizo Janssens Lin Zhang Bart De Moor Wolfgang Glnzel 《Information processing & management》2009,45(6):683-702
A hybrid text/citation-based method is used to cluster journals covered by the Web of Science database in the period 2002–2006. The objective is to use this clustering to validate and, if possible, to improve existing journal-based subject-classification schemes. Cross-citation links are determined on an item-by-paper procedure for individual papers assigned to the corresponding journal. Text mining for the textual component is based on the same principle; textual characteristics of individual papers are attributed to the journals in which they have been published. In a first step, the 22-field subject-classification scheme of the Essential Science Indicators (ESI) is evaluated and visualised. In a second step, the hybrid clustering method is applied to classify the about 8300 journals meeting the selection criteria concerning continuity, size and impact. The hybrid method proves superior to its two components when applied separately. The choice of 22 clusters also allows a direct field-to-cluster comparison, and we substantiate that the science areas resulting from cluster analysis form a more coherent structure than the “intellectual” reference scheme, the ESI subject scheme. Moreover, the textual component of the hybrid method allows labelling the clusters using cognitive characteristics, while the citation component allows visualising the cross-citation graph and determining representative journals suggested by the PageRank algorithm. Finally, the analysis of journal ‘migration’ allows the improvement of existing classification schemes on the basis of the concordance between fields and clusters. 相似文献
184.
Lefèvre W 《Endeavour》2007,31(2):54-58
Did Vermeer van Delft create some of his paintings by means of a camera obscura? This still undecided question has stirred up heated debates. For some, the mere idea is an inexcusable insult on a great artist. All this heat has drawn attention away from a rich seam of questioning: what was the seventeenth-century camera obscura really like? And did it shape the ways in which Vermeer's contemporaries viewed, imagined, understood and, for that matter, rendered the visual world? 相似文献
185.
Buchegger W Haller A van den Driesche S Kraft M Lendl B Vellekoop M 《Biomicrofluidics》2012,6(1):12803-128039
In this study, the pre-steady state development of enzymatic bioreactions using a microfluidic mixer is presented. To follow such reactions fast mixing of reagents (enzyme and substrate) is crucial. By using a highly efficient passive micromixer based on multilaminar flow, mixing times in the low millisecond range are reached. Four lamination layers in a shallow channel reduce the diffusion lengths to a few micrometers only, enabling very fast mixing. This was proven by confocal fluorescence measurements in the channel’s cross sectional area. Adjusting the overall flow rate in the 200 μm wide and 900 μm long mixing and observation channel makes it possible to investigate enzyme reactions over several seconds. Further, the device enables changing the enzyme/substrate ratio from 1:1 up to 3:1, while still providing high mixing efficiency, as shown for the enzymatic hydrolysis using β-galactosidase. This way, the early kinetics of the enzyme reaction at multiple enzyme/substrate concentrations can be collected in a very short time (minutes). The fast and easy handling of the mixing device makes it a very powerful and convenient instrument for millisecond temporal analysis of bioreactions. 相似文献
186.
This study examined whether the learning advantages of an external focus of attention relative to an internal focus, as demonstrated by Wulf, H?ss, and Prinz (1998), would also be found for a sport skill under field-like conditions. Participants (9 women, 13 men; age range: 21-29 years) without experience in golf were required to practice pitch shots. The practice phase consisted of 80 practice trials. One group was instructed to focus on the arm swing (internal focus), whereas another group was instructed to focus on the club swing (external focus). One day after practice, a retention test of 30 trials without instructions was performed. The external-focus condition was more effective for performance during both practice and retention. 相似文献
187.
188.
A. Harry Passow Gilbert de Landsheere A. D. C. Peterson Harold J. Noah Henry Saltzman W. D. Halls Gordon Bishop Richard F. Goodings Helmut von Bracken Franz Hilker Daniel J. Casey Donald E. Super Klaus Schleicher Neville Postlethwaite B. F. Nel Peter Martin Roeder Wolfgang Brezinka Hans Friedrich Eric Ashby Franklin Parker Ernst Prokop Clare Burstall Kenneth Austwick 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1968,14(3):328-375
189.
190.
Geraldine Clarebout Holger Horz Wolfgang Schnotz Jan Elen 《Educational technology research and development : ETR & D》2010,58(5):573-587
The current study investigates whether embedding support may provide a solution to sub optimal use of support and whether
this is related to learners’ self-regulation skills and goal orientation. Sixty students were divided in a condition where
support was embedded and a condition where support was non-embedded. Results reveal that the embedded group used more and
spent more time on the use of support. Quality of use differed for one support device only, with quality being higher in the
non-embedded group. An interaction with self-regulation was found. High self-regulators use the support devices less optimal
when support is embedded. No conclusions could be drawn with respect to goal orientation. Quality of usage and proportional
time spent on support influenced learning outcomes. 相似文献