The relationship between peak height velocity and physical performance in youth soccer players   总被引：1，自引：1，他引：0  

Philippaerts RM  Vaeyens R  Janssens M  Van Renterghem B  Matthys D  Craen R  Bourgois J  Vrijens J  Beunen G  Malina RM 《Journal of sports sciences》2006,24(3):221-230

Longitudinal changes in height, weight and physical performance were studied in 33 Flemish male youth soccer players from the Ghent Youth Soccer Project. The players' ages at the start of the study ranged from 10.4 to 13.7 years, with a mean age of 12.2 +/- 0.7 years. Longitudinal changes were studied over a 5 year period. Peak height velocity and peak weight velocity were determined using non-smoothed polynomials. The estimations of peak height velocity, peak weight velocity and age at peak height velocity were 9.7 +/- 1.5 cm x year-1, 8.4 +/- 3.0 kg x year-1 and 13.8 +/- 0.8 years, respectively. Peak weight velocity occurred, on average, at the same age as peak height velocity. Balance, speed of limb movement, trunk strength, upper-body muscular endurance, explosive strength, running speed and agility, cardiorespiratory endurance and anaerobic capacity showed peak development at peak height velocity. A plateau in the velocity curves was observed after peak height velocity for upper-body muscular endurance, explosive strength and running speed. Flexibility exhibited peak development during the tear after peak height velocity. Trainers and coaches should be aware of the individual characteristics of the adolescent growth spurt and the training load should also be individualized at this time.  相似文献   

Consensus among stakeholders about success factors and indicators for quality of online and blended learning in adult education: a Delphi study     

Yves Blieck  Ilse Ooghe  Chang Zhu  Koen Depryck  Katrien Struyven  Bram Pynoo 《Studies in Continuing Education》2019,41(1):36-60

Quality models for online and blended learning (OBL) have mainly been developed in higher education. The literature indicates that these models are often conceptualised from the providers’ perspective. What is important for the quality of OBL from the students’ perspective has recently received increased attention in the literature. Consensus among stakeholders about students’ quality needs is useful to support dialogue between professionals to strategically adopt OBL and to ensure that the needs of students are met. This study aims to validate a quality instrument for OBL, taking a set of 74 quality indicators and analysing them in terms of seven success factors (credibility, accessibility, transparency, flexibility, interactivity, personalisation, productivity). The Delphi method was selected as most suited. Participants from adult education were asked to indicate on a 7-point Likert scale to what extent the indicators add to OBL quality to meet students’ needs. After four Delphi rounds, the participants agreed on definitions of success factors and 30 indicators. The results are useful for institutions, ministries of education and external quality assessment agencies to assess the quality of OBL and can support institutions to implement improvement actions to ensure that the needs of students are met.  相似文献   

The overall effects of end-of-course assessment on student performance: A comparison between multiple choice testing, peer assessment, case-based assessment and portfolio assessment     

Katrien Struyven  Filip Dochy  Steven Janssens  Wouter Schelfhou  Sarah Gielen 《Studies in Educational Evaluation》2006,32(3):202

This study investigates the effect of method of assessment on student performance. Five research conditions go together with one of four assessment modes, namely: portfolio, case-based, peer assessment, and multiple choice evaluation. Data collection is done by means of a pre-test/ post-test-design with the help of two standardised tests (N=816). Results show that assessment method does make a difference: assessments do not produce overall effects on student performance. Moreover, student-activating instruction efforts do not automatically result in more extensive learning gains. Finally, test results show, when compared to other assessments, a statistically significant positive effect of the multiple choice test on students' test scores. However, students' preparation level and the closed book format of the tests might serve explanatory purposes.  相似文献   

The relation between metastrategic knowledge,strategy use and task performance: Findings and reflections from a numerosity judgement task     

Koen Luwel  Joke Torbeyns  Lieven Verschaffel 《European Journal of Psychology of Education - EJPE》2003,18(4):425-447

In the research literature several positions concerning the role played by metacognition in adaptive strategy choice can be distinguished. While many authors adhere so-called metacognitive models of strategy choice and strategy change, others have questioned the extent to which metacognitive factors are associated with strategy choice and task performance and have proposed alternative theoretical frameworks wherein strategy choices are described in terms of associative models. In the present article we report data coming from a larger research project on the development of children’s numerosity judgement strategies and skills. The experimental task involved judging numerosities of colored blocks presented in a rectangular grid. Participants were 59 second grade and 50 sixth grade children, whose strategic performance data — obtained by means of a systematic analysis of their response-time patterns — were compared with interview data collected at the end of the experiment. The major result of this comparison is that not only the children from the oldest age group, but also the children from the youngest age group showed clear evidence of metacognitive awareness and understanding of different aspects of their strategic performance.  相似文献   

A methodology for the identification of glass panes of different origin in a single stained glass window: Application on two 13th century windows     

Olivier Schalm  Ine De Raedt  Joost Caen  Koen Janssens 《Journal of Cultural Heritage》2010,11(4):81-492

The chemical composition of 11 glass panes originating from two 13th century non-figurative windows were analyzed by means of Scanning Electron Microscopy–Energy Dispersive X-ray system (SEM-EDX). The windows were discovered in the back-wall of the triforium during the restoration of the choir of the cathedral St. Michael and St. Gudule in Brussels (Belgium). In order to determine if these windows were fabricated with glass of different origin or not, the compositional difference between the panes were compared with the variation in composition as a result of the following causes: (1) compositional fluctuation between panes cut from the same sheet of glass, (2) compositional fluctuation caused when panes are cut from different sheets that were made with the same batch, (3) compositional fluctuation caused when the glass is made from different batches at the same production center, and (4) compositional fluctuation as a result of glass produced at different fabrication centers.  相似文献   

Variability of inter-team distances associated with match events in elite-standard soccer     

W Frencken  Hd Poel  C Visscher  K Lemmink 《Journal of sports sciences》2012,30(12):1207-1213

Abstract In soccer, critical match events like goal attempts can be preceded by periods of instability in the balance between the two teams' behaviours. Therefore, we determined periods of high variability in the distance between the teams' centroid positions longitudinally and laterally in an international-standard soccer match and evaluated corresponding match events. Position data were collected with AMISCO Pro?. Inter-team distance variability was calculated over a 3-s moving window. Out of the 242 match periods that exceeded the variability criterion, 51 were dead-ball situations. Match events identified through longitudinal inter-team distance primarily related to defending players moving forward-backward after a longitudinal pass. Match events identified through lateral inter-team distance mainly corresponded with defending players moving laterally following sideways passing. One of two goals and two of fourteen goal-attempts were preceded by a period of high variability. Together, periods of highly variable inter-team distance were associated with collective defensive actions and team reorganisation in dead-ball moments rather than goals or goal attempts. Inter-team dynamics quantified (mutual) reorganisation of the teams and marked teams' collective defensive ability to respond to attacking explorations.  相似文献   

Connected migrants: Encapsulation and cosmopolitanization     

Koen Leurs  Sandra Ponzanesi 《Popular Communication》2018,16(1):4-20

ABSTRACT

Taking a cue from Dana Diminescu’s seminal manifesto on “the connected migrant,” this special issue introduces the notions of encapsulation and cosmopolitanism to understand digital migration studies. The pieces here present a nonbinary, integrated notion of an increasingly digitally mediated cosmopolitanism that accommodates differences within but also recognizes Europe’s colonial legacy and the fraught postcolonial present. Of special interest is an essay by the late Zygmunt Bauman, who argues that the messy boundaries of Europe require a renewed vision of cosmopolitan Europe, based on dialogue and aspirations, rather than on Eurocentrism and universal values. In this article, we focus on three overarching discussions informing this special issue: (a) an appreciation of the so-called “refugee crisis” and the articulation of conflicting Europeanisms, (b) an understanding of the relationships between the concepts of cosmopolitanization and encapsulation, and (c) a recognition of the emergence of the interdisciplinary field of digital migration studies.  相似文献   

The development of computational estimation in the transition from informal to formal mathematics education     

Sekeris  Elke  Empsen  Michaël  Verschaffel  Lieven  Luwel  Koen 《European Journal of Psychology of Education - EJPE》2021,36(3):845-864

European Journal of Psychology of Education - The transition from informal to formal mathematics is an important episode in children’s mathematical development. The current study investigated...  相似文献   

The role of ethnic school segregation for adolescents’ religious salience     

Koen Van der Bracht  Fanny D’hondt  Mieke Van Houtte  Bart Van de Putte  Peter A. J. Stevens 《牛津教育评论》2016,42(2):129-145

Public concerns over the possible effects of school segregation on immigrant and ethnic majority religiosity have been on the rise over the last few years. In this paper we focus on (1) the association between ethnic school composition and religious salience, (2) intergenerational differences in religious salience and (3) the role of ethnic school composition for intergenerational differences in religious salience. We perform analyses on religious salience, one five-point Likert scale item measuring religious salience among 3,612 16-year-old pupils in Belgian secondary schools. National origin was used as a proxy for ethnicity. Ethnic minority pupils in schools with a higher share of ethnic minorities tend to be more religious. This relation holds for Muslim as well as other religious and ethnic minorities. Ethnic school composition also moderates the relationship between migrant generation and religious salience: second generation migrants tend to be more religious in ethnic minority dominated schools. For ethnic Belgians the association is moderated by their religious affiliation: Catholics tend to be more religious, while non-affiliated ethnic Belgians are less religious in schools with a higher share of ethnic minority pupils.  相似文献   

The use of reverse engineering to analyse student computer programs     

Philip Vanneste  Koen Bertels  Bart de Decker 《Instructional Science》1996,24(3):197-221

In this paper, an explanatory program understander that can analyse student solutions for programming assignments is described. The approach uses a number of reverse engineering techniques and is grounded on a cognitive model of procedural programming knowledge. It will be shown that, through the use of reverse engineering techniques, a lot of feedback (e.g. on errors) can be generated without having to use any prior knowledge on what the program is supposed to do. When such information is available, problem-specific feedback can also be generated. Furthermore, the use of the cognitive programming concepts allows one to specify the errors in an understandable way using exactly the same words and concepts as human programmers. This opens interesting possibilities for other uses of the proposed program understanding technique described in this article.  相似文献