The application of inertial measurement units and functional principal component analysis to evaluate movement in the forward 3½ pike somersault springboard dive     

Cherie Walker  John Warmenhoven  Peter J. Sinclair 《Sports biomechanics / International Society of Biomechanics in Sports》2019,18(2):146-162

Based on technological and analytical advances, the capability to more accurately and finitely examine biomechanical and skill characteristics of movement has improved. The purpose of this study was to use Inertial Measurement Units (IMUs) and Functional Principal Components Analysis (fPCA) to examine the role of movement variability (assessed via angular velocity), on 2 divers (1 international level; 1 national) performing the forward 3½ pike somersault dive. Analysis of angular velocity curves during ive-flight identified 5 fPCs, accounting for 96.5% of movement variability. The national diver’s scatter plots and standard deviation of fPC scores illustrated larger magnitudes of angular velocity variability across dive flight. For fPC1 and fPC3, magnitudes of SD variability were 282.6 and 201.5, respectively. The international diver illustrated more consistent angular velocity profiles, with clustering of fPCs scores (e.g., fPC1 & 3 = SD’s of 75.2 & 68.0). To account for lower variability in the international diver, the ability to better coordinate movement sequences and functionally utilise feedback in response to initiation of the somersault position is highlighted. Overall, findings highlight how both IMUs and fPCA can more holistically and finitely examine the biomechanical and skill characteristics of movement sequences with the capability to inform athlete development.  相似文献   

基于用户兴趣度量的知识发现服务精准推荐     

丁梦晓  毕强  许鹏程  李洁  牟冬梅 《图书情报工作》2019,63(3):21-29

[目的/意义]针对当前知识发现服务中存在的个性化程度不高和推荐效果不佳等问题，提出一种基于用户兴趣度量和内容分析的推荐算法。[方法/过程]文章通过特征词分布、LDA主题分布、引文结构网络三个维度构建学术资源模型，并通过对用户行为的度量，计算用户对其浏览学术资源的兴趣度，结合学术资源模型构建用户兴趣模型。将用户兴趣模型与学术资源模型匹配，计算其相似度，得到用户对每条学术资源的兴趣值，最后将兴趣值最高的TOP-N学术资源推荐给用户。[结果/结论]通过实验检验算法的有效性和推荐准确率，结果显示，本文从实时动态度量兴趣的角度，提出的推荐算法能较好地预测用户兴趣，推荐效果显著，为实现发现服务精准推荐提供思路。  相似文献   

数据驱动的微信用户信息行为时间特征研究     

张大勇  孔洪新  许磊  景东 《图书情报工作》2019,63(20):104-111

[目的/意义]相对于传统的信息行为分析，数据驱动的信息行为研究更注重数据的外在性与客观性，所得的结果能够更为全面地认识用户信息行为本质特征。[方法/过程]通过自行构建的APP实现对微信用户分享和阅读行为记录的采集，并对微信用户信息行为的时间特性进行系统的分析。[结果/结论]结果表明：微信用户日常信息行为存在显著的假日效应，但是在信息行为时间间隔分布上存在明显厚尾现象和很强的阵发性，预示着微信用户信息行为具有较高的复杂性和不确定性，无法对其产生过程实现有效的预测；此外，微信用户所分享的内容具有很强的时效性，多数内容在微信中能够得到及时的传播，但传播链长度显著受分享内容主题的影响。  相似文献   

Writer identification approach based on bag of words with OBI features     

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   

Co-occurrence of adverse childhood experiences and its association with family characteristics. A latent class analysis with Dutch population data     

《Child abuse & neglect》2019

BackgroundAlthough adverse childhood experiences (ACEs) are relatively common among children, there is limited knowledge on the co-occurrence of such experiences.ObjectiveThe current study therefore investigates co-occurrence of childhood adversity in the Netherlands and whether specific clusters are more common among certain types of families.Participants and SettingRepresentative data from the Family Survey Dutch population 2018 (N = 3,128) are employed.MethodWe estimate Latent Class Analysis (LCA) models to investigate co-occurrence of ACEs. As ACEs we examine maltreatment, household dysfunction, demographic family events, as well as financial and chronic health problems. Gradual measures for maltreatment and financial problems are studied to make it possible to differentiate with regard to the severity of experiences.ResultsOur results show that four ACE clusters may be identified: ‘Low ACE’, ‘Moderate ACE: Household dysfunction’, ‘Moderate ACE: Maltreatment’ and ‘High ACE’. Regression analyses indicated that mother’s age at first childbirth and the number of siblings were related to experiencing childhood adversity. We found limited evidence for ACEs to be related to a family’s socioeconomic position.ConclusionThe found clusters of ACEs reflect severity of childhood adversity, but also the types of adversity a child experienced. For screening and prevention of childhood adversity as well as research on its consequences, it is relevant to acknowledge this co-occurrence of types and severity of adversity.  相似文献   

‘He is the Vagabond that Hath No Habitation in the Lord’: The Representation of Quakerism as Vagrancy in Interregnum England,c. 1650–1660     

David Hitchcock 《Cultural and Social History》2018,15(1):21-37

This article examines the printed representation, and prosecutorial characterisation, of the movements, actions and motivations of early Quakers as vagrant. It argues that the prevalence and power of representing (and subsequently treating) early Quakers as vagrants is an understudied aspect of the social and cultural history of the Society of Friends, particularly in Interregnum England. As evidence, it interrogates a furious pamphlet debate between mid-century religious writers and preachers, who devoted much time and ink to painting Quakers as mendacious vagabonds, and Quaker ‘First Publishers’, who responded at length and in a striking way to these accusations. The article concludes that these images of Quakerism as a form of ‘spiritual vagrancy’ created historically significant echoes in English and Atlantic culture.  相似文献   

Location extraction from tweets     

Thi Bich Ngoc Hoang  Josiane Mothe 《Information processing & management》2018,54(2):129-144

Five hundred million tweets are posted daily, making Twitter a major social media platform from which topical information on events can be extracted. These events are represented by three main dimensions: time, location and entity-related information. The focus of this paper is location, which is an essential dimension for geo-spatial applications, either when helping rescue operations during a disaster or when used for contextual recommendations. While the first type of application needs high recall, the second is more precision-oriented. This paper studies the recall/precision trade-off, combining different methods to extract locations. In the context of short posts, applying tools that have been developed for natural language is not sufficient given the nature of tweets which are generally too short to be linguistically correct. Also bearing in mind the high number of posts that need to be handled, we hypothesize that predicting whether a post contains a location or not could make the location extractors more focused and thus more effective. We introduce a model to predict whether a tweet contains a location or not and show that location prediction is a useful pre-processing step for location extraction. We define a number of new tweet features and we conduct an intensive evaluation. Our findings are that (1) combining existing location extraction tools is effective for precision-oriented or recall-oriented results, (2) enriching tweet representation is effective for predicting whether a tweet contains a location or not, (3) words appearing in a geography gazetteer and the occurrence of a preposition just before a proper noun are the two most important features for predicting the occurrence of a location in tweets, and (4) the accuracy of location extraction improves when it is possible to predict that there is a location in a tweet.  相似文献   

Crossing the boundaries of imagination: The role of a public library exhibition in global learning for student teachers and teacher educators     

《Teaching and Teacher Education》2020

In this paper, we utilise the theoretical concept of ‘boundary crossing’ to explore how, as Australian university teacher educators, we worked with library curators and a class of student teachers to mount a public exhibition of their group work. We consider how the students crossed ‘boundaries of imagination’ in symbolic representation and critical analysis by creating artistic installations to express global education themes. We reflect on what we, the university educators, learned about crossing institutional and pedagogical boundaries to mutually facilitate new learning. We argue for the importance of shared public pedagogy as offering new avenues for teacher education and of connecting with local communities.  相似文献   

Assessing Determinants of Perceived Ease of Use of Institutional Repositories by Lecturers in Nigerian Universities     

Alice A. Bamigbola  Airen E. Adetimirin 《International Information and Library Review》2020,52(2):95-107

Abstract

Institutional repositories (IRs) present platform to disseminate research findings to complement the traditional scholarly communication model. The use of IRs is beneficial to authors, host institutions, libraries and society at large. Despite the numerous benefits of IRs, there is low deposit of scholarly works by lecturers and the investment on IRs seems to be a waste. This study examined determinants of perceived ease of use (PEOU) of IRs by lecturers in Nigerian universities. A survey of lecturers received 857 respondents. Awareness, anchor and adjustment factors were found to be determinants of PEOU of Institutional repositories by lecturers in Nigerian Universities.  相似文献   

Assessment feedback in examiner reports on master’s dissertations in translation studies     

《Studies in Educational Evaluation》2020

Assessment is a crucial part of degree programmes in higher education. While previous research has been primarily concerned with PhD thesis assessment practice in western countries, this article considers the focus and assessment criteria of 40 examiner reports on master’s dissertations in translation studies at a Chinese university. The results indicate that these examiners structured their reports in four rhetorical moves: ‘preparing the candidate for a decision’, ‘expressing an evaluation’, ‘conveying the decision’, and ‘making recommendations’. These examiners appeared to place more emphasis on the expression of ideas, rather than on the accuracy and originality of those ideas. They apparently adopted flexible working criteria, assessing the dissertations based on institutional requirements and on their own experience. This article concludes with a discussion of implications for dissertation writing.  相似文献