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81.
82.
微型打印机是各种智能化仪表、仪器及各种单片机系统的重要输出设备。本文介绍应用89C51单片机控制微型打印机实现打印功能的设计和实现方法,并给出89C51单片机控制微型打印机的硬件设计及其C语言软件的实现。 相似文献
83.
本文探讨了设计网上银行支付系统所需要的安全技术,对支付系统的安全性进行了研究,设计了支付系统应具备的功能,设计了系统模型和流程,给出了一种网上银行B2C电子支付系统的安全、可靠,便捷的解决方案. 相似文献
84.
Pilar Beneito 《Research Policy》2006,35(4):502-517
The standard empirical framework for analysing the R&D-patents relationship is widened both by examining the different role of in-house and contracted R&D in the innovative performance of firms, and by considering patents and utility models counts as measures of innovation output. Patents and utility models are considered to approximate for significant and incremental innovations, respectively. Applying count data econometrics to a panel data set of Spanish manufacturing firms surveyed in the period 1990-1996, a transcendental production function is estimated, which allows for non-constant elasticities of the R&D inputs. The results indicate that significant innovations are mainly gestated in-house, whereas contracted R&D seems more orientated towards innovations of incremental nature. 相似文献
85.
Catherine D.F. Corolleur 《Research Policy》2004,33(4):631-642
This paper examines how scientific and technological (S&T) human capital is transformed into financial capital through the creation of firms by scientists. The analysis is based on a database describing the positions held by 132 founders from 62 French biotech SMEs. It shows that star scientists engage in highly risky but also valuable firms. Less famous scientists must develop their human capital rather than valorising a stock. The paper concludes by pointing to three paradoxes concerning the commitment and compensation scheme of star scientists and the managerial position of less known scientists. 相似文献
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87.
根据对Elatostema gagnepainianum H. Schröter模式材料的研究,为它指定了后选模式,并将其处理为藤麻Procris crenata C. B. Robinson的新异名。 相似文献
88.
Roger Svensson 《Research Policy》2007,36(7):1052-1069
Using a unique database on Swedish patents owned by small firms and individuals, survival models estimate how different factors influence the decision to commercialize the patents. Such an analysis has seemingly never previously been undertaken. Since the owners know more about the patents than potential external financiers, problems related to asymmetrical information are present. To overcome these problems when inventors and small technology-based firms need financing, Sweden has for a long time relied on government support rather than private venture capital firms. The empirical results show that the larger is the share of patent-owners’ costs covered by government financial support during the R&D phase, the lower is the probability of patents being commercialized. This lower degree of commercialization is likely to depend on (1) the soft terms of the government loans, where the patent owner can avoid paying back the loan if the patent is never commercialized and/or (2) that the government is not able to select promising projects. The first explanation is related to moral hazard and the second one to adverse selection. The policy suggestion is for government to change the design of the loans, to base them on firms rather than projects. 相似文献
89.
19世纪中期,为发展经济、壮大国防,新生的美国政府制定了一系列政策法令鼓励向西部移民,兴修水利,发展农业,修建铁路,开发森林、矿产及土地资源,大大促进了西部地区的发展.至20世纪初,美国一跃成为世界工业经济与军事强国.然而,对西部资源掠夺式的开发行为对生态环境造成了巨大危害,不平等的民族政策严重地损害了土著文化传统,土地投机和完全的市场导向引起了严重的两极分化.本文简要回顾了美国西部开发的过程,比较了中美两国西部开发的异同点,借鉴美国西部开发的经验与教训,提出了对中国西部大开发的几点启示:①重视环境教育,调整思想认识;②加强资源保护,改善生态环境;③制订优惠政策,规范开发行为;④发挥市场导向,重视政府调控;⑤增加资金投入,搞好基础设施;⑥发展教育事业,推进科技创新;⑦坚持民族平等,实现共同富裕. 相似文献
90.
Knowledge-relatedness in firm technological diversification 总被引:4,自引:0,他引:4
This paper claims that knowledge-relatedness is a key factor in affecting firms’ technological diversification. The hypothesis is tested that firms extend the range of their innovative activities in a non-random way. Specifically, we test the extent to which firms diversify their innovative activities across related technological fields, i.e. fields that share a common knowledge base and rely upon common heuristics and scientific principles. The paper proposes an original measure of knowledge-relatedness, using co-classification codes contained in patent documents, and examines the patterns of technological diversification of the whole population of firms from the United States, Italy, France, UK, Germany, and Japan patenting to the European Patent Office from 1982 to 1993. Robust evidence is found that knowledge-relatedness is a major feature of firms’ innovative activities. 相似文献