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Virginie Marie Lefebvre Meri Raggi Davide Viaggi Clarissa Sia‐Ljungström Francesca Minarelli Bianka Kühne Xavier Gellynck 《Creativity & Innovation Management》2014,23(4):415-435
The objective of this paper is to evaluate the importance of selected characteristics of innovation networks in affecting the decision of food SMEs when joining such networks. The paper develops and tests a series of hypotheses through a choice experiment exercise ran on a sample of 231 firms in six EU countries. The results showed that SMEs prefer networks that are composed of manufacturers and supply chain members, where information is shared confidentially among network partners, and when the network provides support to help the firm build its own networks of partners for innovation. In addition, SMEs' choice of the network is also affected by the interaction between specific network attributes and two firm characteristics, i.e. the firm's collaborative experience and innovation objectives. Based on the results, we conclude that the success of inter‐organizational networks depends on the fit between the network's design and the innovation and networking behaviour of the firms. 相似文献
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The simulation of polymer flows is a complicated problem. One of the limiting factors is the degree to which elasticity plays an important role in the flow. For a given constitutive equation and numerical technique, a higher material relaxation time will result in a lower maximum deformation rate for which convergence is possible. Since industrial processes typically involve large deformation rates, a practical way to allow their simulation is to truncate the longest relaxation times. In this work the Leonov constitutive equation was used to simulate flow through an abrupt contraction. The possibility of truncating the relaxation spectrum was explored and the impact of using truncated spectra on simulations is described. Finally, we propose a technique for obtaining a truncated relaxation spectrum that will be useful for flow simulations. 相似文献
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The development of standardized non-culture-based approaches capable of assessing microbial contarnination of airborne dust is sorely needed. Direct chemical analysis has previously been successfully used for measuring components unique to Gram-negative bacteria. In the present study, dust from primary filters of hospital air-conditioning intake systems (which filter incoming outdoor and recirculated air) and dust from secondary room filters (filtering primarily indoor air) were analyzed. Dust from home air-condition-ing filters (which also filter outdoor air, with recirculation) were also analyzed. Muramic acid is an aminosugar present in Gram-positive and Gram-negative bacterial cell walls and can serve as a measure of bacterial contamination in dust. Samples were analyzed by gas chromatography-mass spectrometry after hydrolysis and conversion of released sugars (including muramic acid) to alditol acetates. Primary hospital filters contained 26.3 ± 10.0 ng of muramic acid/mg dust while secondary filters contained 5.3 ± 5.4 ng/mg. The level of inuramic acid in home air-conditioner dust was 31.7 ± 13.4 ng/mg. This study of dust collected from air-conditioners demonstrates the feasibility of chemical assessment of the microbial contamination of indoor air. 相似文献
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An evaluation was performed on the efficiency and emissions from an engine fuelled with compressed natural gas (CNG) and a mixture of natural gas and hydrogen, respectively. The mixtures of CNG and hydrogen were named HCNG. 相似文献
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For the assessment of an under-clad defect in a vessel subjected to a cold pressurised thermal shock, plasticity is considered through the amplification β of the elastic stress intensity factor KI in the ferritic part of the vessel. An important effort has been made recently by CEA to improve the analytical tools in the frame of R&D activities funded by IRSN. The current solution in the French RSE-M code has been developed from fitted F.E. calculation results. A more physical solution is proposed in this paper. This takes into account two phenomena: the amplification of the elastic KI due to plasticity in the cladding and a plastic zone size correction in the ferritic part. 相似文献