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21.
Martin Meyer 《Research Policy》2006,35(10):1646-1662
This paper explores the relationship between scientific publication and patenting activity. More specifically, it examines for the field of nano-science and nano-technology whether researchers who both publish and patent are more productive and more highly cited than their peers who concentrate on scholarly publication in communicating their research results. This study is based on an analysis of the nano-science publications and nano-technology patents of a small set of European countries. While only a very few nano-scientists appear to hold patents in nano-technology, many nano-inventors seem to be actively publishing nano-science research. Overall, the patenting scientists appear to outperform their solely publishing (non-inventing) peers in terms of publication counts and citation frequency. However, a closer examination of the highly active and highly cited nano-authors points to a slightly different situation. While still over-represented among the highly cited authors, inventor-authors appear not to be among the most highly cited authors in that category, with a single notable exception. One policy implication is that, generally speaking, patenting activity does not appear to have an adverse impact on the publication and citation performance of researchers. 相似文献
22.
Recent studies in the tradition of Schmookler have re-emphasised the potential role of demand in stimulating innovation. Here, we reconsider the role of ‘home’ and ‘export’ market demand in stimulating manufacturing innovation using comparable panel data for two small open economies - Ireland and Switzerland. Our analysis is based on the estimation of reduced form innovation production functions using panel data estimators over the sample period 1994-2005. For a range of innovation indicators, however, we find little evidence of any significant market demand effects, with innovation performance instead determined largely by firm-level capability effects and characteristics. In policy and strategy terms this suggests the continued value of measures to improve innovation capability regardless of market demand conditions. In more methodological terms our results suggest the validity of the usual assumption implicit in modelling innovation outputs that supply-side factors predominate. 相似文献
23.
We analyse the impact of R&D cooperation on firm performance differentiating between four types of R&D partners (competitors, suppliers, customers, and universities and research institutes), and considering two performance measures: labour productivity and productivity in innovative (new to the market) sales. Using data on a large sample of Dutch innovating firms in two waves of the Community Innovation Survey (1996, 1998), we examine the impact of R&D cooperation in 1996 on subsequent productivity growth in 1996–1998. The results confirm a major heterogeneity in the rationales and goals of R&D cooperation. Competitor and supplier cooperation focus on incremental innovations, improving the productivity performance of firms. University cooperation and again competitor cooperation are instrumental in creating innovations generating sales of products that are novel to the market, improving the growth performance of firms. Furthermore, customers and universities are important sources of knowledge for firms pursuing radical innovations, which facilitate growth in innovative sales in the absence of formal R&D cooperation. 相似文献
24.
James Rhodes Barry Mason Bertrand Perrat Martin Smith 《Journal of sports sciences》2013,31(17):1639-1647
AbstractThe aim of the current study was to investigate the validity and reliability of a radio frequency-based system for accurately tracking athlete movement within wheelchair court sports. Four wheelchair-specific tests were devised to assess the system during (i) static measurements; (ii) incremental fixed speeds; (iii) peak speeds; and (iv) multidirectional movements. During each test, three sampling frequencies (4, 8 and 16 Hz) were compared to a criterion method for distance, mean and peak speeds. Absolute static error remained between 0.19 and 0.32 m across the session. Distance values (test (ii)) showed greatest relative error in 4 Hz tags (1.3%), with significantly lower errors seen in higher frequency tags (<1.0%). Relative peak speed errors of <2.0% (test (iii)) were revealed across all sampling frequencies in relation to the criterion (4.00 ± 0.09 m · sˉ1). Results showed 8 and 16 Hz sampling frequencies displayed the closest-to-criterion values, whilst intra-tag reliability never exceeded 2.0% coefficient of variation (% CV) during peak speed detection. Minimal relative distance errors (<0.2%) were also seen across sampling frequencies (test (iv)). To conclude, the indoor tracking system is deemed an acceptable tool for tracking wheelchair court match play using a tag frequency of 8 or 16 Hz. 相似文献
25.
The aim of this study was to examine the effects of muscle-tendon length on joint moment and power during maximal sprint starts. Nine male sprinters performed maximal sprint starts from the blocks that were adjusted either to 40 degrees or 65 degrees to the horizontal. Ground reaction forces were recorded at 833 Hz using a force platform and kinematic data were recorded at 200 Hz with a film camera. Joint moments and powers were analysed using kinematic and kinetic data. Muscle - tendon lengths of the medial gastrocnemius, soleus, vastus medialis, rectus femoris and biceps femoris were calculated from the set position to the end of the first single leg contact. The results indicated that block velocity (the horizontal velocity of centre of mass at the end of the block phase) was greater (P < 0.01) in the 40 degrees than in the 65 degrees block angle condition (3.39 +/- 0.23 vs. 3.30 +/- 0.21 m . s(-1)). Similarly, the initial lengths of the gastrocnemius and soleus of the front leg in the block at the beginning of force production until half way through the block phase were longer (P < 0.001) in the 40 degrees than in the 65 degrees block angle condition. The initial length and the length in the middle of the block phase were also longer in the 40 degrees than in the 65 degrees block angle condition both for both the gastrocnemius (P < 0.01) and soleus (P < 0.01-0.05) of the rear leg. In contrast, the initial lengths of the rectus femoris and vastus medialis of the front leg were longer (P < 0.05) in the 65 degrees than in the 40 degrees block angle condition. All differences gradually disappeared during the later block phase. The peak ankle joint moment (P < 0.01) and power (P < 0.05) during the block phase were greater in the 40 degrees than in the 65 degrees block angle condition for the rear leg. The peak ankle joint moment during the block phase was greater (P < 0.05) in the 40 degrees block angle for the front leg, whereas the peak knee joint moment of the rear leg was greater (P < 0.01) in the 65 degrees block angle condition. The results suggest that the longer initial muscle-tendon lengths of the gastrocnemius and soleus in the block phase at the beginning of force production contribute to the greater peak ankle joint moment and power and consequently the greater block velocity during the sprint start. 相似文献
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Birgit Angelika Schmidt Martin Andreas Ziemann Simone Pentzien Toralf Gabsch Werner Koch Jörg Krüger 《文物保护研究》2016,61(2):113-122
A great number of Central Asian wall paintings, archeological materials, architectural fragments, and textiles, as well as painting fragments on silk and paper, make up the so called Turfan Collection at the Asian Art Museum in Berlin. The largest part of the collection comes from the Kucha region, a very important cultural center in the third to ninth centuries. Between 1902 and 1914, four German expeditions traveled along the northern Silk Road. During these expeditions, wall paintings were detached from their original settings in Buddhist cave complexes. This paper reports a technical study of a wall painting, existing in eight fragments, from the Buddhist cave no. 40 (Ritterhöhle). Its original painted surface is soot blackened and largely illegible. Grünwedel, leader of the first and third expeditions, described the almost complete destruction of the rediscovered temple complex and evidence of fire damage. The aim of this case study is to identify the materials used for the wall paintings. Furthermore, soot deposits as well as materials from conservation interventions were of interest. Non-invasive analyses were preferred but a limited number of samples were taken to provide more precise information on the painting technique. By employing optical and scanning electron microscopy, energy dispersive X-ray spectroscopy, micro X-ray fluorescence spectroscopy, X-ray diffraction analysis, and Raman spectroscopy, a layer sequence of earthen render, a ground layer made of gypsum, and a paint layer containing a variety of inorganic pigments were identified. 相似文献
30.
The main purpose of this article is to advance an alternative perspective on the relationship between intrinsic and extrinsic motivation, and in particular to examine critically the assertion that these processes are antagonistic such that the will to learn for its own sake is inhibited by the presence of extrinsic, tangible rewards and incentives such as school grades. The presumption of an antagonistic relationship largely depends on the theoretical perspective adopted. An alternative interpretation based on need achievement theory leads to distinctly different conclusions. Exploring this new perspective allows one to identify both the conditions under which intrinsic motives may coexist with extrinsic motives as well as to consider some of the means by which intrinsic motives and caring about learning can be stimulated in their own right in school settings. 相似文献