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61.
International knowledge spillovers, especially through multinational companies (MNCs), have recently been a major topic of academic and management debate. However, most studies treat MNC subsidiaries as relatively passive actors. We challenge this assumption by investigating the drivers of knowledge protection intensity of MNC subsidiaries. We argue that knowledge protection intensity is determined by MNC subsidiary mandates and by opportunities and risks originating from the host region. We hypothesize that not just competence-creating but also competence-exploiting mandates increase knowledge protection intensity. In addition, technological cluster regions in the host country can be expected to provide opportunities for knowledge sourcing and MNC subsidiaries may be willing to protect knowledge less intensively to participate in cluster networks. We test our hypotheses using a dataset of 694 observations of 631 MNC subsidiaries in Germany and develop recommendations for research, managers and policy makers. 相似文献
62.
含钒的化合物能够有效地催化H2O2,因此可作为多元Fenton-like催化剂中的有效组份之一,Fe2V4O13中存在Fe(Ⅲ)和V(V)同时和协同活化H2O2的可能性。通过液相合成法制备了Fe2V4O13,并对其对AOⅡ的催化活性进行了研究,研究表明,Fe2V4O13是一种新型高效稳定的多相Fenton-like催化剂。 相似文献
63.
采用O*NET工作分析系统中的工作技能、工作风格和工作价值观问卷对660名高校体育教师进行调查,研究表明:高校体育教师O*NET工作技能问卷包含专业技能、认知技能和社会技能,工作风格问卷包含关系导向、事业导向和创新导向,工作价值观问卷包括工作条件、自我实现、独立自主和环境支持,各因子均具有良好的内部一致性信度;O*NET问卷所包含的因子在任务完成情况、学生体育成绩、学生比赛成绩和教学研究成果四个方面对高校体育教师的工作绩效起到正向预测作用;高校体育教师的教龄能显著正向预测学生比赛成绩和教学研究成果两方面的工作绩效,职称高的体育教师取得高工作绩效的可能性大于职称低的。 相似文献
64.
统计了2012年伦敦奥运会皮划艇1 000mK1、K2、K4、C1和C2共5个项目决赛前三名的分段成绩,分析与归纳分段成绩呈现出的特点,对提升中国皮划艇长距离项目训练和比赛水平提出了建议。 相似文献
65.
66.
Marco S Giarratana 《Research Policy》2004,33(5):787-806
The paper analyses the birth of the encryption software industry (ESI), a new niche in the software industry. Using a Chandlerian perspective, this work reports the main facts about firm entry and growth, with a particular focus on start-up strategies and actions.Since scale economies do not play a major role in ESI, the paper investigates the different sources of firm competitive advantages.This work shows that innovation and product differentiation, along with investments in co-specialised assets, are variables strongly correlated to young firm probability to survive and grow. In doing so, we have collected highly detailed information on product introduction, US patents granted, worldwide alliances and biographical data of firm founders. 相似文献
67.
The determinants of regional innovation in Europe: A combined factorial and regression knowledge production function approach 总被引:3,自引:0,他引:3
The present paper studies the determinants of regional innovation in Europe through a knowledge production function approach that combines factorial analysis and regression. Our dependent variable are the patents while we used initially 21 explanatory variables that were converted—by a factor analysis—into five non-observable “hypothetical” variables reflecting five important aspects of the innovation systems: the National environment, the Regional environment, Innovating firms, Universities and the R&D done by Public Administration. Our results show that all factors have a statistically significant effect on the production of knowledge (patents), although they present very different impacts. 相似文献
68.
Business cycles modify firms’ incentives to innovate and the direction of innovation. By introducing a new measure of patent unconventionality this paper explores the impact of the business cycle on firms’ technological search strategies. We find that during upturns firms generate inventions characterized by a higher level of technological unconventionality. We also find that financially resilient and diversified firms produce more unconventional patents. While patent unconventionality is associated with technological impact and market value, firms extract more value by investing in unconventional inventions in downturns. 相似文献
69.
文章研究了185nm紫外光/氧化协同降解水体中微量三氯甲烷的降解情况,考察了溶液浓度、光解时间、溶液pH值以及加入氧化剂等对降解三氯甲烷的影响,研究结果表明,CHCl3的脱氯基本是由185nm紫外光引起;其脱氯率几乎不受pH值的影响;在近中性条件下,5mg.L-1的三氯甲烷水溶液的CODMn去除率、脱氯率均与光解时间呈指数上升;光解5min后,CODMn去除率可达50%左右,脱氯率则小于30%;CHCl3的解离主要是185nm光子的作用,而与其它氧化性物质无关。 相似文献
70.
Daniel W. Kee Susan Nakayama Siaw Linda Carter 《Contemporary educational psychology》1985,10(3):268-274
An experiment was conducted to evaluate constructive memory in fourth-grade low-SES black and middle-SES white children. The children were read nine short passages; each passage was composed of two premise statements and a filler sentence. The children were tested by a recognition procedure. Thirty-six test sentences were presented randomly. Four sentences were associated with each passage (true premise, false premise, true inference, and false inference). Subjects were asked to make yes/no recognition decisions based on whether the test sentence was identical to a sentence presented at study. Middle-SES white children made few errors, except to true inference test sentences. This pattern of performance is consistent with the constructive view of memory. Low-SES black children also had a high error rate to true inference items. However, this outcome may not reflect constructive memory because they also had a high error rate to some of the other types of test sentences. 相似文献