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11.
ABSTRACTThis article suggests that situations in which multiple research teams are convened under similar conditions present an opportunity to discover factors that lead to productive collaboration. It argues that social network analysis of research team outputs becomes more valuable when paired with data about research participant perceptions; and that any variables used as indicators of collaboration need to be calibrated using datasets from multiple studies with cross-team comparisons. The article provides an example of the kind of methodology needed to achieve this, describing a study with data from four research teams based at an Australian university campus, reporting their research performance over four years under conditions in which many variables were controlled and with results augmented by a survey of participant perceptions. Findings from the study indicate that there were exceptions to hypothesized associations between participant perceptions of collaboration and specific social network analysis measures over co-authorship data. The article suggests that, given the methodological challenges of studying research teams in the field, multiple datasets combining findings such as those in the present study are a path towards the development of indicators of productive higher education research collaboration. 相似文献
12.
首先对中国知网数据库中收录的以警察体育为主题的文献时序分布进行梳理,通过论文发表时间与数量的变量关系对比,分析揭示该研究领域的历史脉络、发展速度以及演变规律。随后利用信息可视化软件Bibexcel绘制出警察体育研究领域的核心作者、研究机构、高被引文献的知识图谱,阐释该领域的研究结构、力量分布以及合作平台建设等情况。最后运用词频分析、共词聚类和可视化法生成关键词共现网络图谱,挖掘、提炼文献数据背后的规律与逻辑,捕捉警察体育研究领域中的研究热点和前沿动态,并在此基础上深入探讨警察体育未来研究的基本趋势和发展方向。 相似文献
13.
Amal Durou Ibrahim Aref Somaya Al-Maadeed Ahmed Bouridane Elhadj Benkhelifa 《Information processing & management》2019,56(2):354-366
Handwriter identification aims to simplify the task of forensic experts by providing them with semi-automated tools in order to enable them to narrow down the search to determine the final identification of an unknown handwritten sample. An identification algorithm aims to produce a list of predicted writers of the unknown handwritten sample ranked in terms of confidence measure metrics for use by the forensic expert will make the final decision.Most existing handwriter identification systems use either statistical or model-based approaches. To further improve the performances this paper proposes to deploy a combination of both approaches using Oriented Basic Image features and the concept of graphemes codebook. To reduce the resulting high dimensionality of the feature vector a Kernel Principal Component Analysis has been used. To gauge the effectiveness of the proposed method a performance analysis, using IAM dataset for English handwriting and ICFHR 2012 dataset for Arabic handwriting, has been carried out. The results obtained achieved an accuracy of 96% thus demonstrating its superiority when compared against similar techniques. 相似文献
14.
蒋晓帆 《体育科技文献通报》2020,(1):155-157
运用中国知网(CNKI)检索库进行检索,共查找到期刊文献115篇,其中国内期刊65篇,硕士论文31篇。通过Cite Space和中国知网(CNKI)文献分析功能,对国内身体功能训练研究进行计量学分析。研究的基本特征表现为:研究机构多,文献期刊发表数量较少,核心期刊占比较少,论文质量与数量之间存在差异。研究热点以身体功能训练为主,并突显了“功能训练”“训练”和“体育工作者”等关键词,作者合作比较少,仅形成数个微小的作者合作网络。 相似文献
15.
David Sánchez-Oliva Rebecca M. Leech Alberto Grao-Cruces Irene Esteban-Cornejo Carmen Padilla-Moledo Oscar L. Veiga 《Journal of sports sciences》2020,38(9):1062-1069
ABSTRACTThe aims of this study were to identify profiles of sedentary behaviour (SB) patterns, based on leisure-time self-reported SB modalities (screen, educative, social, and relaxing) and to evaluate changes in these profiles over 2 years among Spanish youth aged 8–18 years. Latent profile analysis (LPA), a data-driven analytic approach, was used to identify groups of boys and girls (n = 1553; 48% girls; mean±SD age: 12.56 ± 2.49 y) with distinct SB profiles using the SB modalities (time/d) as input variables. Latent transition analysis, an extension of LPA that uses longitudinal data, was used to analyse 2-year changes in these profiles. At baseline, four and three SB profiles were found among boys (labelled: screen, educative, social, and relaxing) and girls (labelled: screen/social, educative, and relaxing), respectively. Overall, more girls (range: 48%-67%) had the same profile over time, than boys (40%-52%). Participants with a screen or relaxing SB profile at baseline were more likely to have an educative profile after 2 years. Youth with a social and an educative SB profile at baseline were more likely to transition to profiles characterized by higher screen and social SB, respectively. Using a novel and person-centered approach, this study identified gender-specific SB profiles that were moderately stable over time. 相似文献
16.
BackgroundResearch on achievement goal orientations in sport has typically relied on the use of variable-centered approaches that tend to overlook population heterogeneity. In this study, we used a person-centered approach to identify subgroups of competitive tennis players according to unique combinations of achievement goal orientations and tested for subgroup differences in motivation and mental toughness.MethodsA sample of 323 competitive tennis athletes (69.35% male) between 15 and 25 years of age (17.60 ± 2.40 years, mean ± SD) completed the 3 × 2 Achievement Goal Questionnaire for Sport, Sport Motivation Scale II, and Mental Toughness Index. Latent profile analysis was used to identify unique combinations of achievement goal orientations. Comparisons between latent subgroups on autonomous motivation, controlled motivation, and mental toughness were performed using analysis of variance.ResultsLatent profile analysis supported 3 distinct patterns of achievement goal profiles that were primarily distinguishable based on valence of competence (i.e., approach vs. avoidance). Analyses of variance indicated that athletes who were classified into subgroups that endorsed approach types of goals (regardless of the types of avoidance goals they endorsed) reported higher levels of autonomous motivation and mental toughness.ConclusionResults indicated that athletes tend to pursue a number of achievement goals collectively rather than in isolation. Although approach goals are more commonly linked to adaptive psychological functioning and positive outcomes, avoidance goals may also be associated with desirable psychological characteristics if they are pursued in conjunction with approach types of achievement goals. 相似文献
17.
BackgroundPlanctomycetes is a phylum of biofilm-forming bacteria with numerous biosynthetic gene clusters, offering a promising source of new bioactive secondary metabolites. However, the current generation of chemically defined media achieves only low biomass yields, hindering research on these species. We therefore developed a chemically defined medium for the model organism Planctopirus limnophila to increase biomass production.ResultsWe found that P. limnophila grows best with a 10 mM sodium phosphate buffer. The replacement of complex nitrogen sources with defined amino acid solutions did not inhibit growth. Screening for vitamin requirements revealed that only cyanocobalamin (B12) is needed for growth. We used response surface methodology to optimize the medium, resulting in concentrations of 10 g/L glucose, 34 mL/L Hutner’s basal salts, 23.18 mM KNO3, 2.318 mM NH4Cl and 0.02 mg/L cyanocobalamin. The analysis of amino acid consumption allowed us to develop a customized amino acid solution lacking six of the amino acids present in Aminoplasmal 10%. Fed-batch cultivation in a bioreactor using the optimized medium achieved a final ΔOD600 of 46.8 ± 0.5 after 108 h, corresponding to a cell dry weight of 13.6 ± 0.7 g/L.ConclusionsThe optimized chemically defined medium allowed us to produce larger amounts of biomass more quickly than reported in earlier studies. Further research should focus on triggering P. limnophila biofilm formation to activate the gene clusters responsible for secondary metabolism.How to cite: Kruppa OC, Gerlach D, Fan R, et al. Development of a chemically defined medium for Planctopirus limnophila to increase biomass production. Electron J Biotechnol 2021;54. https://doi.org/10.1016/j.ejbt.2021.09.002. 相似文献
18.
为更好地了解国外体育创新创业领域研究的前沿热点和发展趋势,明晰我国发展的不足。运用文献计量法、数理统计法等对1968—2018年Web Of Science(SSCI、SCI等核心库)中的收录的123篇文献进行了计量分析。结果表明:国外体育创新创业领域已取得一定的成果,但也仍存在作者合作脉络单一、实证研究单薄、案例分析不够全面等问题,建议国内应取长补短,从巩固理论研究、深入实证研究、加强协作脉络、延伸企业家精神内涵等方面入手,以期更好地促进我国体育创新创业领域的发展。 相似文献
19.
20.
ABSTRACT This study used the 2017 Las Vegas and 2016 Orlando mass shootings as case studies to explore alleged double standards in reporting of events featuring Muslim and non-Muslim mass perpetrators of violence. The study used framing theory and content analysis to examine Los Angeles Times and New York Times coverage of the shootings during the one week immediately following each event. Findings are consistent with previous literature and the researchers’ expectations. The Orlando shooting, carried out by a Muslim, was allotted more coverage despite the fact that it produced nine fewer fatalities than the Las Vegas shooting, perpetrated by a white non-Muslim. The analysis also showed that the examined newspapers were more likely to employ a “terrorism” frame in their coverage of the Orlando shooting than in their coverage of the Las Vegas shooting; link the Orlando mass shooting with the global war on terrorism; and to humanize Stephen Paddock, the white perpetrator of the Las Vegas shooting. Framing differences found in this study may contribute to downplaying the threat of white male gun violence, and to reinforcing fears of Islam and Muslims. 相似文献