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1.
[目的/意义]研究时间因素对专利被引频次的影响,可以减少时间因素对技术评价活动的制约,提高评价的准确性和可信度。[方法/过程]采集1975-2017年的美国专利数据,开展基于固定效应法的专利被引频次的修正研究。将专利按照不同公开年份和不同技术领域分组,选定组内均值和6个TOP分位数为被引频次基准,统计当前时间点的被引频次基准线及基准线的历史时序变化情况。建立神经网络模型,拟合基准线的时序变化规律,并预测未来统计时间点的基准线。[结果/结论]专利公开年份和统计年份的时间差异,使得专利被引频次无法直接进行比较。本文建立了基于不同技术领域、不同公开年份和不同统计年份的专利被引频次基准线,为专利评估提供参考。 相似文献
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[目的/意义] 两个国家间的创新合作机会有些是显性直接的,有些是潜在间接的。在此试图构建一种计量和分析专利引用关系的方法,用于发现两国间潜在的间接创新合作机会。[方法/过程] 全球价值链上不同环节专利之间的引用关系中,蕴含着相互衔接、配套的间接合作关系,而不同环节的专利通常具有不同的功能,即IPC存在一定跨越度。因此,设计"专利引用跨越度"指标及算法,用于计量和筛选专利引用网络中"引用跨越度"达到预设阈值的专利引用关系,作为发现间接创新合作机会的基础数据。以新加坡在中国获得授权的发明专利为样本,基于专利引用跨越度计量并配合人工解读和识别,发现中新两国间一系列的间接创新合作机会。[结果/结论] 基于专利引用跨越度计量的两国间间接创新合作机会发现的方法,被实验检验为有效。 相似文献
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Critical educational literature suggests that an increased reliance upon performative technologies is currently transforming the very foundations from which teacher subjectivities are constructed. Arguably though, the number of studies pointing to this risk or tendency is considerably larger than the ones theorising why this should be the case. Further, in those cases where the relationship between performative technologies and teacher subjectivities is theorised, the psychological mechanisms that the technologies appeal to are seldom brought to the fore. Based on this, the purpose of this article is to theorise the psychological mechanisms that performative technologies appeal to and work through, by means of identifying, systematising and elaborating extant understandings of such mechanisms in the critical educational literature. The results are presented in the form of a conceptual framework (referred to as the CMIS-framework) which suggests that one and the same performative technology may play many different roles, where each such role appeals to and works through a particular psychological mechanism. Importantly, depending on the type of psychological mechanism that is appealed to, the CMIS-framework suggests that this will lead to teachers (un)consciously conducting particular forms of subjectivising work upon themselves, here referred to as compliance, mirroring, identification and self-realisation (CMIS). 相似文献
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In this digital ITEMS module, Dr. Jeffrey Harring and Ms. Tessa Johnson introduce the linear mixed effects (LME) model as a flexible general framework for simultaneously modeling continuous repeated measures data with a scientifically defensible function that adequately summarizes both individual change as well as the average response. The module begins with a nontechnical overview of longitudinal data analyses drawing distinctions with cross-sectional analyses in terms of research questions to be addressed. Nuances of longitudinal designs, timing of measurements, and the real possibility of missing data are then discussed. The three interconnected components of the LME model—(1) a model for individual and mean response profiles, (2) a model to characterize the covariation among the time-specific residuals, and (3) a set of models that summarize the extent that individual coefficients vary—are discussed in the context of the set of activities comprising an analysis. Finally, they demonstrate how to estimate the linear mixed effects model within an open-source environment (R). The digital module contains sample R code, diagnostic quiz questions, hands-on activities in R, curated resources, and a glossary. 相似文献
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In an expertise study with 94 mathematics teachers varying in their relative teacher expertise (i.e., student teachers, trainee teachers, in-service teachers), we examined effects of teachers' professional knowledge and motivational beliefs on their ability to integrate technology within a lesson plan scenario. Therefore, we assessed teachers' professional knowledge (i.e., content knowledge, pedagogical content knowledge, technological knowledge), and their motivational beliefs (i.e., self-efficacy, utility-value). Furthermore, teachers were asked to develop a lesson plan for introducing the Pythagorean theorem to secondary students. Lesson plans by advanced teachers (i.e., trainee teachers, in-service teachers) comprised higher levels of instructional quality and technology exploitation than the ones of novice teachers (i.e., pre-service teachers). The effect of expertise was mediated by teachers' perceived utility-value of educational technology, but not by their professional knowledge. These findings suggest that teachers’ motivational beliefs play a crucial role for effectively applying technology in mathematics instruction. 相似文献
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U. Casellato F. Fenzi P. Guerriero S. Sitran P. A. Vigato U. Russo M. Galgani M. Mendera A. Manasse 《Journal of Cultural Heritage》2003,4(4):337-353
A significant number of archaeological finds of the 13th–16th century from the Tuscan sites of Germagnana and Gambassi in Valdelsa—FI, was studied by different physico-chemical investigations (SEM–EDS, ICP, Mössbauer spectroscopy, XRD, XRF, TG-DTA) in order to contribute to clarify the production methodology and the pre-industrial glass manufacture technology. The studied samples are mainly non-vitreous finds as production waste, refractory materials, crucibles and raw materials; also vitreous finds as frits, skims, glasses (glass masses, glass working waste and finished products) have been taken into consideration. The obtained petrographic and physico-chemical data strongly suggest that both Gambassi and Germagnana glass manufactures were strictly connected with the sources of vitrifiable materials, situated in Tuscan sand quarries. In particular a comparison between sands from the neighbouring quarries and appropriate finds of the two archaeological sites evidences that the employed vitrifiable materials possibly belong to La Casina La Cava resort. The archaeological classification, based on macroscopic observation and stratigraphic position, was compared and verified with the scientific classification of the examined finds of Germagnana and Gambassi sites based on their composition, morphology and physico-chemical properties. 相似文献
8.
女子大众艺术健身操锻炼效果的实验研究 总被引:9,自引:0,他引:9
以 6 0名 18岁以上女子为研究对象 ,采用自编的四套大众艺术健身操 ,每周进行三次练习 ,每次 6 0分钟。持续练习 8周。结果表明 :大众艺术健身操练习可以减小女子身体各部位的围度 ,具有改善女子的形体特征的作用。不仅有非常明显的减肥作用 ,而且具有增加瘦体重从而改变身体成分 ,达到增强体质的作用。对于体重超重和肥胖者 ,减肥和降体重 ,改善身体成分的作用更为显著。大众艺术健身操对提高女子呼吸系统、循环系统机能水平也有一定的作用。对提高女子的力量、灵敏性、平衡能力及反应速度等身体素质有显著的作用。 相似文献
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跳远助跑速度变化对起跳效果的影响——国内外优秀运动员与我院选手的比较分析 总被引:1,自引:0,他引:1
程万才 《西安体育学院学报》2003,20(2):78-79
笔者采用高速摄影、影片解析、数理统计等方法对西安体育学院男子跳远运动员和国内外优秀选手助跑速度变化而影响起跳效果的因素进行比较研究。结果表明:跳远助跑各段落速度的变化对起跳效果及成绩产生很大影响;西安体育学院男子跳远运动员绝对速度低,起跳前两步速度、速度利用率呈下降趋势,影响起跳初速度;跳远起跳前一步的速度、速度利用率对提高起跳效果要比起跳前9—10m段的速度、速度利用率更具有实际意义。 相似文献
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