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This paper examines how the role of patents and utility models in innovation and economic growth varies by level of economic development. Using a panel dataset of over 70 countries, we find that patent protection is an important determinant of innovation and that patentable innovations contribute to economic growth in developed countries, but not in developing. Instead, in developing economies, a minor form of intellectual property rights (IPRs) - namely utility models - is conducive to innovation and growth, controlling for other factors. Using Korean firm level data as a case study, we find that utility model innovations contribute to firm performance when firms are technologically lagging and that those minor innovations can be a learning device and thus a stepping stone for developing more patentable inventions later on. Upon reaching higher levels of technological capabilities, firms become more reliant upon patents and less on utility models. Thus the lesson here is that patent protection enhances innovation and economic growth in countries where the capacity to conduct innovative research exists. Where this capacity is weaker, a system that provides incentives to conduct minor, incremental inventions is more conducive to growth. The significance of this paper is to emphasize the importance not just of the strength of IPRs but of the appropriate type of IPRs for economic development.  相似文献   
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IntroductionIt is unclear what is the best strategy for applying patient-based real-time quality control (PBRTQC) algorithm in the presence of multiple instruments. This simulation study compared the error detection capability of applying PBRTQC algorithms for instruments individually and in combination using serum sodium as an example.Materials and methodsFour sets of random serum sodium measurements were generated with differing means and standard deviations to represent four simulated instruments. Moving median with winsorization was selected as the PBRTQC algorithm. The PBRTQC parameters (block size and control limits) were optimized and applied to the four simulated laboratory data sets individually and in combination.ResultsWhen the PBRTQC algorithm were individually optimized and applied to the data of the individual simulated instruments, it was able to detect bias several folds faster than when they were combined. Similarly, the individually applied algorithms had perfect error detection rates across different magnitudes of bias, whereas the error detection rates of the algorithm applied on the combined data missed smaller biases. The performance of the individually applied PBRTQC algorithm performed more consistently among the simulated instruments compared to when the data were combined.DiscussionWhile combining data from different instruments can increase the data stream and hence, increase the speed of error detection, it may widen the control limits and compromising the probability of error detection. The presence of multiple instruments in the data stream may dilute the effect of the error when it only affects a selected instrument.  相似文献   
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This study provides a glimpse into understanding the potential benefits as well as harm of playing video games from the perspective of six Malaysian secondary school students, aged 16-17 years old. The rationale of the study is to enable parents, educators, administrators and policy makers to develop a sound understanding on the impact of playing video games before making any judgment on the contemporary youth culture. Thus, further decision on the acceptance of video games as a new innovation in school or at home could be considered. Although this study is not very extensive, the findings suggest that playing video games contributes to cognitive, social, motivational and emotional development. However, potential harms do exist. Parents play an important role in guiding their children either directly or indirectly, as indicated by the respective students. Caution is advised in the interpretation of the study's findings as it is solely based on the perspectives of the students, as the first person's views. Nevertheless, each student has their very own perspective on the impact of video games on them.  相似文献   
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A key tenet of the Home–School Knowledge Exchange Project is that children's learning will be enhanced if the knowledge and experience that are to be found both at home and in school can be brought together. In this paper we explore ways of connecting home and school to support literacy learning at Key Stage 1, focusing on the home‐to‐school direction. We discuss how shoeboxes, filled with children's artefacts, can support a range of literacy‐related activities in school. It is suggested that the extensive diversity of knowledge and interests reflected in the chosen objects presents teachers with an invaluable opportunity to personalise children's literacy learning.  相似文献   
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ABSTRACT

Advocacy is a complex set of applications that applies knowledge of human behavior in the social environment to promote the rights of others. The purpose of this study was to explore the usefulness of student-created public service announcements (PSAs) to help BSW students learn cause-based advocacy. Our results suggest that assigning a PSA project supports competencies in cause-based advocacy, professional identity development social work, critical thinking, engagement with research-informed practice, and capacity to respond to contexts.  相似文献   
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游子文化:历史、现实与未来   总被引:1,自引:1,他引:0  
本文从游子文化的历史演进和现实状况出发,分析它的现实作用和发展趋向,以及它对华侨、华人社会发生的深刻影响,作者认为以亲缘、地缘、神缘、业缘、物缘人际关系网络为表现形式的中华游子文化,无论与中国社会的现实还是未来都密切相关,特别是对中国的改革开放及和平统一大业起着巨大的促进作用  相似文献   
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Vocabulary knowledge was tested in a native (Cantonese-Chinese) and foreign (English) language in 150 twins and 150 singletons aged 6–11 years, matched on age, gender, grade level, nonverbal intelligence, parents’ education, family income, and number of siblings and household members. The singletons clearly outperformed the twins on the native vocabulary, but this “twinning effect” was much less noticeable for the foreign vocabulary. The effect on English vocabulary was further reduced after exposure to English at home was controlled. Given that these participants learned most of their English in school rather than home, the present findings support the notion that the twinning effect is associated with increased competition for family interaction in twins compared with singletons.  相似文献   
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We present a new approach to enhance mixing in T-type micromixers by introducing a constriction in the microchannel under periodic electro-osmotic flow. Two sinusoidal ac electric fields with 180° phase difference and similar dc bias are applied at the two inlets. The out of phase ac electric field induces oscillation of fluid interface at the junction of the two inlet channels and the constriction. Due to the constriction introduced at the junction, fluids from these two inlets form alternative plugs at the constricted channel. These plugs of fluids radiate downstream from the constriction into the large channel and form alternate thin crescent-shaped layers of fluids. These crescent-shaped layers of fluids increase tremendously the contact surface area between the two streams of fluid and thus enhance significantly the mixing efficiency. Experimental results and mixing mechanism analysis show that amplitude and frequency of the ac electric field and the length of the constriction govern the mixing efficiency.  相似文献   
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