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1.
Benjamin Kane Williams Ross H. Sanders Joong Hyun Ryu Pitre C. Bourdon Philip Graham-Smith Peter J. Sinclair 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(2):202-214
Magnetic-inertial measurement units (MIMUs) are becoming more prevalent in sports biomechanics and may be a viable tool to evaluate kinematic parameters. This study examined the accuracy of a MIMU to estimate orientation angles under static conditions and dynamically from a squash racket during a forehand drive shot. A MIMU was mounted onto a goniometer and moved through 0–90°, with static data collected at 10° increments during 10 repetitions of all three axes. Typical error analyses showed the MIMU to be very reliable (TE ≤ 0.03°). MIMU accuracy was determined via intraclass correlation coefficients (ICC) (r > 0.999, p < 0.001). An ordinary least products regression showed no proportional bias and minimal fixed bias for all axes. Dynamic accuracy was assessed by comparing MIMU and optical motion capture data of squash racket swing kinematics. A MIMU was fixed onto a racket and 10 participants each hit 10 forehand shots. Mean orientation angle error at ball impact was <0.50° and ICC showed very high correlations (r ≥ 0.988, p < 0.001) for all orientations. Swing phase root mean squared errors were ≤2.20°. These results indicate that a MIMU could be used to accurately and reliably estimate selected racket swing kinematics. 相似文献
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School readiness of maltreated children: Associations of timing,type, and chronicity of maltreatment
Children who have been maltreated during early childhood may experience a difficult transition into fulltime schooling, due to maladaptive development of the skills and abilities that are important for positive school adaptation. An understanding of how different dimensions of maltreatment relate to children’s school readiness is important for informing appropriate supports for maltreated children. In this study, the Australian Early Development Census scores of 19,203 children were linked to information on child maltreatment allegations (substantiated and unsubstantiated), including the type of alleged maltreatment, the timing of the allegation (infancy-toddlerhood or preschool), and the total number of allegations (chronicity). Children with a maltreatment allegation had increased odds of poor school readiness in cognitive and non-cognitive domains. Substantiated maltreatment was associated with poor social and emotional development in children, regardless of maltreatment type, timing, or chronicity. For children with unsubstantiated maltreatment allegations, developmental outcomes according to the type of alleged maltreatment were more heterogeneous; however, these children were also at risk of poor school readiness irrespective of the timing and/or chronicity of the alleged maltreatment. The findings suggest that all children with maltreatment allegations are at risk for poor school readiness; hence, these children may need additional support to increase the chance of a successful school transition. Interventions should commence prior to the start of school to mitigate early developmental difficulties that children with a history of maltreatment allegations may be experiencing, with the aim of reducing the incidence of continuing difficulties in the first year of school and beyond. 相似文献
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在对近年来创新管理领域普遍使用的创新术语进行全面梳理的同时,构建创新概念框架体系,并以维度特征为视角对各创新术语进行特征类比和类型区分,探究相关发展趋势和各个创新类型在中国创新环境下的实践应用。 相似文献
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根据2003—2015年我国31个省份技术市场发展的基本数据,采用莫兰指数(Moran’s I)分析我国技术市场发展的时空分布特征,利用空间误差模型探究技术市场发展对经济增长的促进作用。研究发现:(1)2003—2015年间各省份技术市场发展存在显著的正向空间关系,但空间集聚程度有所减弱;(2)各省份技术市场发展的空间格局相对稳定,但空间差异显著性有所降低,临近省份技术市场成交额影响下的人均地区生产总值具有明显的集聚特点,各省份技术市场发展下的经济增长之间呈现显著的正向空间相关;(3)分类型技术市场发展模型中,技术服务对经济的产出弹性系数(0.4380)明显高于技术咨询的产出弹性(0.2754)。 相似文献
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以创新驱动发展为研究视角,界定承载研发创新功能的新型研发机构的内涵和形成动因,研究不同信息条件下新型研发机构的作用机理。通过建立数理分析模型发现,在完全信息条件下,通过组织间合作建立新型研发机构,各参与方能够获得经济收益和非经济收益,即使在没有经济收益的极端情况下,参与方也可以获得非经济收益,如学习能力、创新能力、管理能力的提升。在不完全信息条件下,创新研发风险越高,通过各方合作建立新型研发机构,获得的研发创新收益越大。并提出相关建议,以提高新型研发机构的创新能力。 相似文献
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随着我国教育改革不断推进,基础教育美术课程改革也进入深水区,美术教育发展面临许多新问题、新情况和新挑战,其中,要求美术教师专业化成为许多矛盾汇聚的焦点。在职美术教师的发展起点在于职前培养,而培养职前美术教师的关键之一是相关课程的设置与实施过程。故从我国学校美术课程观历史发展脉络出发,倡导建立美术课程内容与教育哲学观念、理解与实践之间紧密联系的观点,基于“实践智慧”,提出组织具有批判性质、经验性质和体验性质三种特点的高等师范学院美术教师教育课程模式设置与实施思路。 相似文献
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《Research Policy》2019,48(7):1855-1865
Quantitative research evaluation requires measures that are transparent, relatively simple, and free of disciplinary and temporal bias. We document and provide a solution to a hitherto unaddressed temporal bias – citation inflation – which arises from the basic fact that scientific publication is steadily growing at roughly 4% per year. Moreover, because the total production of citations grows by a factor of 2 every 12 years, this means that the real value of a citation depends on when it was produced. Consequently, failing to convert nominal citation values into real citation values produces significant mis-measurement of scientific impact. To address this problem, we develop a citation deflator method, outline the steps to generalize and implement it using the Web of Science portal, and analyze a large set of researchers from biology and physics to demonstrate how two common evaluation metrics – total citations and h-index – can differ by a remarkable amount depending on whether the underlying citation counts are deflated or not. In particular, our results show that the scientific impact of prior generations is likely to be significantly underestimated when citations are not deflated, often by 100% or more of the nominal value. Thus, our study points to the need for a systemic overhaul of the counting methods used evaluating citation impact – especially in the case of researchers, journals, and institutions – which can span several decades and thus several doubling periods. 相似文献
10.
Jie Mei Aminul Islam Abidalrahman Moh’d Yajing Wu Evangelos Milios 《Information processing & management》2018,54(6):874-887
Modern OCR engines incorporate some form of error correction, typically based on dictionaries. However, there are still residual errors that decrease performance of natural language processing algorithms applied to OCR text. In this paper, we present a statistical learning model for post-processing OCR errors, either in a fully automatic manner or followed by minimal user interaction to further reduce error rate. Our model employs web-scale corpora and integrates a rich set of linguistic features. Through an interdependent learning pipeline, our model produces and continuously refines the error detection and suggestion of candidate corrections. Evaluated on a historical biology book with complex error patterns, our model outperforms various baseline methods in the automatic mode and shows an even greater advantage when involving minimal user interaction. Quantitative analysis of each computational step further suggests that our proposed model is well-suited for handling volatile and complex OCR error patterns, which are beyond the capabilities of error correction incorporated in OCR engines. 相似文献