Archeological excavation monitoring using dense stereo matching techniques     

Matteo Dellepiane  Nicolò Dell’Unto  Marco Callieri  Stefan Lindgren  Roberto Scopigno 《Journal of Cultural Heritage》2013,14(3):201-210

Several new tools to obtain three-dimensional information from unorganized image sets are now available for the public use. The main advantage of this software, which is based on dense stereo matching, is the possibility to generate 3D content without the need of high-cost hardware (e.g. 3D scanning devices). Nevertheless, their use in real-world application domains (like cultural heritage) is still not very diffused, due to the non-straightforward usability of the raw data produced. In this paper, we investigate the use of automatic dense stereo reconstruction tools for the monitoring of an excavation site. A methodology for the effective acquisition and processing of data is presented. In addition, the results of the data assessment demonstrate the repeatability of the data acquisition process, which is a key factor when qualitative analysis is performed. The use of three-dimensional data is integrated in an open source mesh processing tool, thus showing that a spatio-temporal analysis can be performed in a very intuitive way using off-the-shelf or free/open digital tools. Moreover, the use of peculiar rendering and the creation of snapshots from arbitrary points of view increase the amount of documentation data, and suggest a perfect integration of data produced with dense stereo matching in the future standard documentation for excavation monitoring.  相似文献   

Dribbling speed along curved paths predicts attacking performance in match-realistic one vs. one soccer games     

Robbie S Wilson  Nicholas M A Smith  Solange de Paula Ramos  Fabio Giuliano Caetano  Marcio Aparecido Rinaldo  Paulo Roberto Pereira Santiago 《Journal of sports sciences》2019,37(9):1072-1079

This study assessed whether a new, closed-skill dribbling or sprinting task could predict attacking performance in soccer. Twenty-five male players were recruited from the Londrina Junior Team Football Academy in Brazil and asked to either dribble the ball or sprint through five custom circuits that varied in average curvature (0–1.37 radians.m^?1). These measures were then validated using a realistic one vs. one competition in which each player acted as attacker or defender in turn (N = 1330 bouts). Sprinting (ICC = 0.96) and dribbling (ICC = 0.97) performances were highly repeatable for individual players. Average dribbling speed decreased non-linearly with increasing circuit curvature (F = 239.5; P < 0.001) from 5.19 ± 0.11 ms^?1 on the straightest path to 2.13 ± 0.03 ms^?1 on the curviest. Overall, dribbling but not sprinting performance predicted attacking success in the one vs. one competition, explaining more than 50% of the variation in attacking success alone (r_p = 0.70; P < 0.001). In conclusion, our new closed-skill dribbling assessment is a valid and reliable protocol to predict a soccer player’s success in attacking performance in one vs. one situation, and can be used to identify talented players.  相似文献   

Performance,motivation, and enjoyment in young female basketball players: An interdisciplinary approach     

André L. A. Soares  Thiago J. Leonardi  Jaqueline Silva  Juarez V. Nascimento  Roberto R. Paes  Carlos E. Gonçalves 《Journal of sports sciences》2020,38(8):873-885

ABSTRACT

The purpose of this study was to examine the variation in accumulated basketball training experience, body size, functional performance, deliberate practice motivation, achievement and competitiveness motivation and sources of enjoyment among young female basketball players, partitioning the potential variation by individuals´ biological characteristics (menarche status) and contextual characteristics (competitive age group and competitive level). We considered 114 adolescent female basketball players aged 14.3 (1.8) years. We used multilevel regression and poststratification estimations. The adolescent female basketball players selected for state-level had more accumulated experience, were taller and with better functional performance. Conditional on the data, youth female coaches tend to value (probably overvalue) size and function when selecting/promoting players, even at early age groups, likely contributing to an overrepresentation of early maturing girls in at early age groups. Players from club- and state-level were similarly highly motivated for deliberate practice and to achievement. Only for competitiveness, state-level players had higher values than club level players. The sources of enjoyment were influenced by context (competitive levels) for self-referenced competencies and others-referenced competencies. Structured programs of training and competition in youth female basketball provide a nurturing environment for the development of players´ engagement and commitment to training and excellence attainment.  相似文献   

Analytics for learning design: A layered framework and tools     

Davinia Hernández-Leo  Roberto Martinez-Maldonado  Abelardo Pardo  Juan A. Muñoz-Cristóbal  María J. Rodríguez-Triana 《British journal of educational technology : journal of the Council for Educational Technology》2019,50(1):139-152

The field of learning design studies how to support teachers in devising suitable activities for their students to learn. The field of learning analytics explores how data about students' interactions can be used to increase the understanding of learning experiences. Despite its clear synergy, there is only limited and fragmented work exploring the active role that data analytics can play in supporting design for learning. This paper builds on previous research to propose a framework (analytics layers for learning design) that articulates three layers of data analytics—learning analytics, design analytics and community analytics—to support informed decision-making in learning design. Additionally, a set of tools and experiences are described to illustrate how the different data analytics perspectives proposed by the framework can support learning design processes.  相似文献   

Cross-cultural adaptation and psychometric properties of the Portuguese version of the youth experience survey for sport (P-YES-S)     

Patrícia Aparecida Gaion Rigoni  José Roberto Andrade do Nascimento Junior  Isabella Caroline Belem  Lenamar Fiorese Vieira 《Measurement in physical education and exercise science》2018,22(4):310-321

This study investigated adaptation and the psychometric properties of the Portuguese version of the Youth Experience Survey for Sport (P-YES-S). Translators, professors, and athletes participated. Athletes between 14 and 18 years were recruited. The instrument was the P-YES-S. Content validity was assessed by coefficients of content and kappa, while Cronbach’s alpha was used for internal consistency analysis and intraclass correlation for temporal stability. Exploratory and confirmatory factorial analyses were conducted to test the construct validity of the instrument. Discriminant validity was assessed by comparing the Average Variance Extracted (AVE) with the squared correlation between factors. Results showed acceptable levels for content validity, internal consistency, temporal stability, concurrent validity, and construct validity. The acceptable model was: X²/df = 1.54, GFI = 0.93, CFI = 0.92; AGFI = 0.92, TLI = 0.91, AIC = 414.63, BIC = 610.93, MECVI = 1.41 and RMSEA = 0.0.04, p = 0.03. The adaptation process produced an instrument with 22 items and the dimensions of Personal and Social Skills, Cognitive Skills, Initiative Experiences, and Negative Experiences.  相似文献   

Some numerical tests for an alternative approach to optimal feedback control     

Roberto Font  Pablo Pedregal 《Journal of The Franklin Institute》2018,355(15):7011-7026

We test a recently proposed approach to optimal feedback control of nonlinear systems leading to an iterative descending strategy [24]. We start by discussing the numerical implementation of this strategy, and propose a number of improvements that can speed up the computation process by up to two orders of magnitude. The resulting algorithm is then applied to a series of test problems of increasing complexity. Results seem to show that this can be a promising strategy to bear in mind for more realistic situations.  相似文献   

Bullying in Italian schools: the role of perceived teacher unfairness     

Massimo Santinello  Alessio Vieno  Roberto De Vogli 《European Journal of Psychology of Education - EJPE》2011,26(2):235-246

The principal aim of the study is to examine the role of perceived teacher unfairness in predicting bullying behaviour. Data were taken from the “Health Behaviour in School Aged Children” project, a cross-sectional survey investigating health behaviours among early adolescents in selected European countries. Bullying behaviour (bully, victim, and bully/victim), perceived teacher unfairness and others confounding factors were measured through a self-administered questionnaire filled out by a representative sample of 4,386 (48.4% males) Italian students (11, 13, and 15 years old). Covariates included demographic characteristics, socioeconomic status, school performance and other psychological factors. After adjusting for age and gender, teacher unfairness showed a significant association with being a bully (OR = 1.59; CI = 1.40–1.80) and a bully or victim (OR = 1.47; CI = 1.21–1.78). This relationship remained significant after additional adjustment for several potential confounding factors. Results show that characteristics of the school setting such as teacher unfairness can be significant predictors of involvement in bullying behaviour among early adolescents.  相似文献   

天文学家能把星星数完吗?     

GuntherHasinger  青艺龙 《科学中国》2002,(6):45-51

好像每天的报纸都在报道天文学上的新发现:新的天体,新的物理过程,新的物质形式,等等.这种没完没了的发现哪天才到头呢?是否有一天天文学家会自信已经清点完了宇宙的全部资产?  相似文献   

Advanced displays and natural user interfaces to support learning     

Juan-Fernando Martin-SanJose  Ramón Mollá  Roberto Vivó 《Interactive Learning Environments》2017,25(1):17-34

Advanced displays and natural user interfaces (NUI) are a very suitable combination for developing systems to provide an enhanced and richer user experience. This combination can be appropriate in several fields and has not been extensively exploited. One of the fields that this combination is especially suitable for is education. Nowadays, children are growing up playing with computer games, using mobile devices, and other technological devices. New learning methods that use these new technologies can help in the learning process. In this paper, two new methods that use advanced displays and NUI for learning about a period of history are presented. One of the methods is an autostereoscopic system that lets children see themselves as a background in the game and renders the elements in 3D without the need for special glasses; the second method is a frontal projection system that projects the image on a table in 2D and works similarly to a touch table. The Microsoft Kinect^© is used in both systems for the interaction. A comparative study to check different aspects was carried out. A total of 128 children from 7 to 11 years old participated in the study. From the results, we observed that the different characteristics of the systems did not influence the children's acquired knowledge, engagement, or satisfaction. There were statistically significant differences for depth perception and presence in which the autostereoscopic system was scored higher. However, of the two systems, the children considered the frontal projection to be easier to use. We would like to highlight that the scores for the two systems and for all the questions were very high. These results suggest that games of this kind (advanced displays and NUI) could be appropriate educational games and that autostereoscopy is a technology to exploit in their development.  相似文献   

On the use of extended TAM to assess students' acceptance and intent to use third‐generation learning management systems          下载免费PDF全文

Salvador Ros  Roberto Hernández  Agustín Caminero  Antonio Robles  Isabel Barbero  Araceli Maciá  Francisco Pablo Holgado 《British journal of educational technology : journal of the Council for Educational Technology》2015,46(6):1250-1271

Service‐oriented e‐learning platforms can be considered as a third generation of learning management systems (LMSs). As opposed to the previous generations, consisting of ad hoc solutions and traditional LMS, this new technology contemplates e‐learning systems as services that can be integrated into different learning scenarios. This paper shows that the flexibility of these systems allows building personal learning environments and proposes the use of an extended technology acceptance model (TAM) to assess the acceptance and intention to use a third generation of LMS. To fit and validate the service‐oriented e‐learning platforms acceptance model, structural equation modeling and path analysis have been implemented. The results point out that the intention to use this third‐generation LMS is determined by the gadgets and container design, both of which are structural elements of this technology. Finally, it is also shown that previous experience does not determine the use intention of this technology.  相似文献