Knowledge construction and diverging thinking in elementary & advanced mathematics     

Eddie Gray  Marcia Pinto  Demetra Pitta  David Tall 《Educational Studies in Mathematics》1999,38(1-3):111-133

This paper begins by considering the cognitive mechanisms available to individuals which enable them to operate successfully in different parts of the mathematics curriculum. We base our theoretical development on fundamental cognitive activities, namely, perception of the world, action upon it and reflection on both perception and action. We see an emphasis on one or more of these activities leading not only to different kinds of mathematics, but also to a spectrum of success and failure depending on the nature of the focus in the individual activity. For instance, geometry builds from the fundamental perception of figures and their shape, supported by action and reflection to move from practical measurement to theoretical deduction and euclidean proof. Arithmetic, on the other hand, initially focuses on the action of counting and later changes focus to the use of symbols for both the process of counting and the concept of number. The evidence that we draw together from a number of studies on children's arithmetic shows a divergence in performance. The less successful seem to focus more on perceptions of their physical activities than on the flexible use of symbol as process and concept appropriate for a conceptual development in arithmetic and algebra. Advanced mathematical thinking introduces a new feature in which concept definitions are formulated and formal concepts are constructed by deduction. We show how students cope with the transition to advanced mathematical thinking in different ways leading once more to a diverging spectrum of success.This revised version was published online in September 2005 with corrections to the Cover Date.  相似文献   

Risk factors in e-justice information systems     

João Rosa  Cláudio Teixeira  Joaquim Sousa Pinto 《Government Information Quarterly》2013

With the increase of the communication systems' bandwidth and with the dissemination of the information systems, the fields of information and communication technology application expanded in almost all directions. E-government in general and e-justice in particular are no exception and these areas suffered strong changes in the last decades. There is no democracy without a system of swift and transparent justice. Therefore, the introduction of information systems in the courts allows a decrease both in time and number of pending processes, boosting the efficiency of the services provided to citizens and to the society in general.  相似文献   

‘That is like a 24 hours-day tournament!’: using social media to further an authentic sport experience within sport education     

Carla Luguetti  Victoria Anne Goodyear  Mauro Henrique André 《Sport, Education and Society》2019,24(1):78-91

Several studies demonstrate that Sport Education supports the development of an authentic experience of sport. Social media has the potential to further the development of an authentic sport experience since it is a key aspect of contemporary sport culture and can be a space for individuals to interact during the Sport Education. Yet the evidence-base on the use of social media within Sport Education is limited. The purpose of this study was to explore how social media supports the development of an authentic sport experience within Sport Education. The context of this study was within a female recreational community sport futsal club. Players engaged with Sport Education as a focus for their sessions for 13 weeks. The Sport Education season embedded the six key features. During the Sport Education season, players interacted with each other through Facebook. Data were generated from; (1) researcher/player field journal, (2) Facebook posts and (3) post-season player interviews. Data analysis involved inductive, constant comparison and member-checking methods. Results showed that players’ uses of Facebook supported the development of an authentic sport experience. Players’ uses of Facebook strengthened the development of three key Sport Education features; affiliation, festivity and season. Based on the limited amount of research on the impact of social media within Sport Education and community sport, future studies should continue to examine the effectiveness of social media as an interactional tool to enhance the development of an authentic sport experience.  相似文献   

Effects of distinct practice conditions on the learning of the o soto gari throwing technique of judo     

Fábio Rodrigo Ferreira Gomes  Flavio Henrique Bastos  Cássio de Miranda Meira Jr.  Jaqueline Freitas de Oliveira Neiva  Go Tani 《Journal of sports sciences》2017,35(6):572-578

The aim of this study was to investigate the effects of different types of practice on learning the o soto gari, focusing on the kuzushi (unbalancing the opponent). A total of 64 children (mean age 9.19 ± 1.41 years) were assigned to one of four groups: (1) static traditional practice, i.e., uchikomi – repetition of the moving pattern that characterises the technique up to the point of throwing; (2) in motion traditional practice – uchikomi with the tori (player executing the technique) moving/walking; (3) whole practice with pre-kuzushi – full technique with a preparatory component for kuzushi; (4) progressive parts practice with pre-kuzushi – progressively introducing kuzushi, tsukuri (set-up to execute the technique) and kake (final part of the technique; projection) with pre-kuzushi. Pre-test, acquisition, post-test and retention test were carried out. Movements were video recorded and analysed regarding three aspects: global technique of the tori, occurrence of a movement pattern performed by the tori to unbalance the uke (player receiving the “attack”), and occurrence of actual unbalance (kuzushi). Results showed no significant differences between-groups. However, different within-groups improvements suggest that using a uchikomi with pre-kuzushi can help learners deal with the motor actions of pulling and pushing in order to unbalance the opponent.  相似文献   

Patterns of bibliographic references in the ACM published papers     

Jacques Wainer  Henrique Przibisczki de Oliveira  Ricardo Anido 《Information processing & management》2011

This paper analyzes the bibliographic references made by all papers published by ACM in 2006. Both an automatic classification of all references and a human classification of a random sample of them resulted that around 40% of the references are to conference proceedings papers, around 30% are to journal papers, and around 8% are to books. Among the other types of documents, standards and RFC correspond to 3% of the references, technical and other reports correspond to 4%, and other Web references to 3%. Among the documents cited at least 10 times by the 2006 ACM papers, 41% are conferences papers, 37% are books, and 16% are journal papers.  相似文献   

Effect of Ultrasonic Pretreatment on Melon Drying and Computational Fluid Dynamic Modelling of Thermal Profile     

Joo Henrique Fernandes da Silva  Jos Sabino da Silva Neto  Edilene Souza da Silva  Danilo Emídio de Souza Cavalcanti  Patrícia Moreira Azoubel  Mohand Benachour 《Food Technology and Biotechnology》2020,58(4):381

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An Activist Approach to Sport Meets Youth From Socially Vulnerable Backgrounds: Possible Learning Aspirations     

Carla Luguetti  Kimberly L. Oliver  Luiz Eduardo Pinto Basto Tourinho Dantas  David Kirk 《Research quarterly for exercise and sport》2017,88(1):60-71

Purpose: This study was a 2-phase activist research project aimed at co-creating a prototype pedagogical model for working with youth from socially vulnerable backgrounds in a sport context. This article addresses the learning aspirations (learning outcomes) that emerged when we created spaces for youth to develop strategies to manage the risks they face in their community. Method: This study took place in a socially and economically disadvantaged neighborhood in a Brazilian city where we worked with a group of 17 boys aged 13 to 15 years old, 4 coaches, a pedagogic coordinator, and a social worker. During a 6-month period, we collected multiple sources of data including field journal entries/observations (38) and audio records of youth work sessions (18), coaches' work sessions (16), combined coaches and youth work sessions (3), and meetings between the lead and the 2nd author for debriefing and planning sessions (36). Results: By using an activist approach, 4 learning aspirations emerged: becoming responsible/committed, learning from mistakes, valuing each other's knowledge, and communicating with others. Conclusion: Findings suggest there is a need for more sports programs that start from young people's concrete needs and life situations and look to create places for youth to see alternative possibilities and take action.  相似文献   

Do students notice stress in teachers? Associations between classroom teacher burnout and students' perceptions of teacher social–emotional competence     

Eva Oberle  Alexander Gist  Muthutantrige S. Cooray  Joana B. R. Pinto 《Psychology in the schools》2020,57(11):1741-1756

The goal of the present study was to investigate the link between elementary school teacher burnout and students' perceptions of teacher social–emotional competence (SEC). A total of 676 Grades 4–7 students in 35 classrooms rated their classroom teachers' SEC. In addition, teachers self-reported their current level of experienced burnout at work (i.e., depersonalization and emotional exhaustion). Multilevel analyses revealed significant classroom-level variability (i.e., 34%) in student-ratings of teacher SEC. Teacher burnout significantly predicted student-rated teacher SEC, over and above significant student-level variables (school self-concept, sense of autonomy in the classroom) and contextual variables (teacher age, school neighborhood income). Specifically, higher levels of teacher burnout were related to receiving lower SEC ratings by students. Teacher burnout explained a significant portion of the classroom-level variability in student-rated teacher SEC. The present study emphasizes the link between teacher burnout and the SEC. Furthermore, given that teacher reports (burnout) were linked to student reports (teacher SEC), these findings also suggest that students notice stress in their classroom teacher.  相似文献   

Predicting centre of mass horizontal speed in low to severe swimming intensities with linear and non-linear models     

Kelly de Jesus  Helon Vicente Hultmann Ayala  Leandro dos Santos Coelho  João Paulo Vilas-Boas  Ricardo Jorge Pinto Fernandes 《Journal of sports sciences》2019,37(13):1512-1520

We aimed to compare multilayer perceptron (MLP) neural networks, radial basis function neural networks (RBF) and linear models (LM) accuracy to predict the centre of mass (CM) horizontal speed at low-moderate, heavy and severe swimming intensities using physiological and biomechanical dataset. Ten trained male swimmers completed a 7 × 200 m front crawl protocol (0.05 m.s^?1 increments and 30 s intervals) to assess expiratory gases and blood lactate concentrations. Two surface and four underwater cameras recorded independent images subsequently processed focusing a three-dimensional reconstruction of two upper limb cycles at 25 and 175 m laps. Eight physiological and 13 biomechanical variables were inputted to predict CM horizontal speed. MLP, RBF and LM were implemented with the Levenberg-Marquardt algorithm (feed forward with a six-neuron hidden layer), orthogonal least squares algorithm and decomposition of matrices. MLP revealed higher prediction error than LM at low-moderate intensity (2.43 ± 1.44 and 1.67 ± 0.60%), MLP and RBF depicted lower mean absolute percentage errors than LM at heavy intensity (2.45 ± 1.61, 1.82 ± 0.92 and 3.72 ± 1.67%) and RBF neural networks registered lower errors than MLP and LM at severe intensity (2.78 ± 0.96, 3.89 ± 1.78 and 4.47 ± 2.36%). Artificial neural networks are suitable for speed model-fit at heavy and severe swimming intensities when considering physiological and biomechanical background.  相似文献   

Polycentric organizing and performance: A contingency model and evidence from megaproject planning in the UK     

Nuno Gil  Jeffrey K. Pinto 《Research Policy》2018,47(4):717-734

This study sheds light on polycentric forms of organizing and corresponding performance implications. Organizations with a polycentric architecture supplement their internal hierarchical decision-making structures with egalitarian, local structures in order to encourage collaboration with legally independent stakeholders. We ground our study on the planning stage for four capital-intensive infrastructure development projects (megaprojects) in the UK. We first establish that megaproject planning is carried on by polycentric organizations. We show that in this form of organizing the promoter has decision-making authority over the high-order choices, but shares the authority over the local choices with groups of autonomous stakeholders. We also show how this organizational architecture addresses local disputes and pressures to relax performance targets. Our main contribution is a contingency model that proposes four conditions linking performance to polycentric organizing, whether or not: i) the institutional environment empowers an ‘umpire’ to referee disputes; and ii) the system leader can mobilize substantial slack resources to reconcile conflicting interests. We argue that the four conditions reveal very different classes of managerial problems, and draw implications for practice and policy including but not limited to megaprojects.  相似文献