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981.
介绍了SIMADYN D全数字控制系统在高线生产线上的应用,实践证明,该系统能有效提高交流调速传动控制系统的设计、调试效率,具有控制精度高、响应快速、操作可靠及易于维护的优良品质。 相似文献
982.
In this paper, we utilize transmission-line matrix simulations to study the electromagnetic properties of hyperbolic metamaterial grids, which are synthesized by arranging unloaded transmission lines over electrical ground planes, such that the unit cells are rectangular in shape. The hyperbolic grids support Bragg and Hyperbolic resonant modes that have rectangular and hyperbolic dispersion surfaces, respectively. We demonstrate the formation of these resonant modes in the hyperbolic grids and their refraction, and spatial scanning properties via circuit simulations. The simulation results are compared with experimental results of a two-layer anisotropic hyperbolic metamaterial. 相似文献
983.
The effectiveness of university knowledge spillovers: Performance differences between university spinoffs and corporate spinoffs 总被引:2,自引:0,他引:2
While much prior research has focused upon how the Technology Transfer Offices (TTOs) and other contextual characteristics shape the level of university spinoffs (USO), there is little research on entrepreneurial potential among individual academics, and to the best of our knowledge, no comparative studies with other types of spinoffs exist to date. In this paper we focus on an important but neglected aspect of knowledge transfer from academic research involving the indirect flow to entrepreneurship by individuals with a university education background who become involved in new venture creation by means of corporate spinoffs (CSO) after gaining industrial experience, rather than leaving university employment to found a new venture as an academic spinoff. We argue that the commercial knowledge gained by industry experience is potentially more valuable for entrepreneurial performance compared to the academic knowledge gained by additional research experience at a university. This leads us to posit that the average performance of CSOs will be higher than comparable USOs, but the gains from founder‘s prior experiences will be relatively higher among USOs whose founders lack the corporate context. We investigate these propositions in a comparative study tracking the complete population of USOs and CSOs among the Swedish knowledge-intensive sectors between 1994 and 2002. 相似文献
984.
Although age is not supposed to be a criterion for the award of the Nobel Prize, it is commonly believed that it does play a role. Indeed, econometric evidence in this paper also suggests such a role. However, the paper finds that, if there is a preference for older Nobel candidates, this is introduced during the nomination process. The paper actually finds that the Nobel Committee does not favor older nominees and that, if anything, it seems to partially offset the age premium introduced by the nominators. 相似文献
985.
This paper addresses the role that scientific status plays in initial public offerings of technology focused firms. The paper builds on the literature of the sociology of science as well as the work of Spence (1974) and Podolny (1993) and argues that the presence of a Nobel laureate affiliated with a firm making an IPO provides a signal of firm quality to potential investors. Moreover, and building on the work of Podolny and Scott Morton (1999) and Stuart et al. (1999) we hypothesize that the importance of status diminishes as other measures of firm quality become available. We test our hypothesis for two periods of initial public offerings in biotechnology. We document that there is a clear difference in “maturity” of the firms across the two windows on a number of metrics. Consistent with our hypothesis that Nobel laureates play an important role as a non-financial signal of firm quality, we find that first-window firms with a Nobel laureate affiliate realize greater IPO proceeds in the amount of $24 million. In the second window the amount of money raised is not significantly different between Nobel and non-Nobel firms. This finding is consistent with the signaling literature that argues that the importance of a signal is inversely related to the availability of cogent information on firm quality. Consistent with this view, we also find a change between the two windows in the importance of other non-financial metrics used to convey value. Our research is one of the first to examine the dynamic nature of signals. Because we are unable to distinguish the extent to which the reduction in uncertainty at the firm level is correlated with the reduction of uncertainty at the industry level, the question remains as to the extent to which the diminished importance of signals in our second period is due to a change in market uncertainty versus a change in firm uncertainty. 相似文献
986.
Regional investment in R&D, technological development and innovation is perceived as being strongly associated with productivity, growth and sustained international competitiveness. One policy instrument by which policy makers have attempted to create regional advantage has been the establishment of publicly funded research centres (PRCs). In this paper we develop a logic model for this type of regional intervention and examine the outputs and longer-term outcomes from a group of (18) publicly funded R&D centres. Our results suggest some positive regional impacts but also identify significant differences in terms of innovation, additionality and sustainability between university-based and company-based PRCs. University-based PRCs have higher levels of short-term additionality, demonstrate higher levels of organisational innovation but prove less sustainable. Company-based PRCs demonstrate more partial additionality in the short-term but ultimately prove more sustainable. 相似文献
987.
This paper contributes to the ongoing debate on the impact of academic patenting on publishing and knowledge transfer. Drawing upon two separate surveys of academics, and their CV information, we provide empirical evidence for UK academics in engineering and physical sciences. The contribution of this paper is two-fold. First, our findings show that (the intensity of) academic patenting complements publishing up to a certain level of patenting output, after which we find evidence of a substitution effect. We also find weak evidence of important differences across scientific fields with the more basic-oriented fields showing indications of a crowding-out effect. Second, our analysis of the potential impact of patenting on knowledge transfer shows a positive correlation between the stock of patents and engagement in knowledge transfer channels. However, we find that a substitution effect sets in, indicating an inverted U-shaped relationship between patenting and several knowledge transfer channels. 相似文献
988.
This article develops a general framework to describe the changes in university IPR regulations in Europe and their effects on the patenting activities of universities and on knowledge transfer processes. Understanding the effects of changes in IPR regulations on academic patenting is a complex issue, and parallels with the US case can be misleading. First, despite the general trend towards institutional ownership, university IPR regulations in Europe remain extremely differentiated and there is no one-to-one mapping to the US system. Second, it is difficult to disentangle the quantitative and qualitative effects of changes in IPR ownership regulations on academic patenting activities from the effects of concurrent transformations in the institutional, cultural and organizational landscape surrounding academic knowledge transfer. The article proposes a review and typological classification of national university IPR ownership systems on the basis of their development since 2000, and uses it to analyze the aggregate dynamics of academic patent ownership in several European countries. The analysis of patterns of ownership of academic patents shows that there has been a general increase in university patenting since 1990, with a significant slowdown (and even reduction in some countries) after early 2000s accompanied by a switch in academic patents ownership in favor of university ownership though preserving the European specificity of high company ownership of academic invented patents. 相似文献
989.
Although sources and determinants of academic entrepreneurship have begun to command the attention of policy-makers and researchers, there remain many unanswered questions about how individual and social factors shape the decisions of academics to engage in entrepreneurial activities. Using a large-scale panel of academics from a variety of UK universities from 2001 to 2009, this paper examines how an academics’ level of entrepreneurial capacity in terms of opportunity recognition capacity, and their prior entrepreneurial experience shape the likelihood of them being involved in starting up a new venture. In addition, we explore what role university Technology Transfer Offices (TTOs) play in stimulating venture creation. The results show that individual-level attributes and experience are the most important predictors of academic entrepreneurship. We also find that the social environment surrounding the academic also plays an influential role, but its role is much less pronounced than individual-level factors. Finally, we show that the activities of the TTO play only a marginal, indirect role, in driving academics to start new ventures. We explore the implications of this analysis for policy and organizational design for academic entrepreneurship. 相似文献
990.
Tércia Zavaglia TorresAuthor VitaeIvo Pierozzi Jr.Author Vitae Nadir Rodrigues PereiraAuthor VitaeAlexandre de CastroAuthor Vitae 《International Journal of Information Management》2011,31(2):121-127
The great contemporary organizational challenge for enterprises is to create a conceptual and methodological framework allows the management of knowledge by means of networks designed for social interaction. This statement is based on the premise that the competitive drive and sustainable success of the company depend on the introduction of new forms of production innovative processes, which can only be ensured through integrated approaches to knowledge management and the incorporation information technologies (IT). This is a reality that has already been accepted by the Brazilian Agricultural Research Corporation (Embrapa, its acronym in Portuguese), a Brazilian research, development, and innovation (RD&I) institution supporting agricultural sector. For some years now, Embrapa has been incorporating what it has learned about knowledge management into its strategic planning process. In this paper, we present a new approach to managing knowledge and information, and we analyze the need for research institutions to administer the knowledge they produce through an RD&I management model based multi- and inter-disciplinary teams, and multi-institutional research networks. 相似文献