Percorrer por autor "Couceiro, Micael"
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- Accuracy of pattern detection methods in the performance of golf puttingPublication . Couceiro, Micael; Dias, Gonçalo; Mendes, Rui; Araújo, DuarteThe authors present a comparison of the classification accuracy of 5 pattern detection methods in the performance of golf putting. The detection of the position of the golf club was performed using a computer vision technique followed by the estimation algorithm Darwinian particle swarm optimization to obtain a kinematical model of each trial. The estimated parameters of the models were subsequently used as sample of five classification algorithms: (a) linear discriminant analysis, (b) quadratic discriminant analysis, (c) naive Bayes with normal distribution, (d) naive Bayes with kernel smoothing density estimate, and (e) least squares support vector machines. Beyond testing the performance of each classification method, it was also possible to identify a putting signature that characterized each golf player. It may be concluded that these methods can be applied to the study of coordination and motor control on the putting performance, allowing for the analysis of the intra- and interpersonal variability of motor behavior in performance contexts.
- Activity profiles of soccer players during the 2010 World CupPublication . Clemente, Filipe Manuel; Couceiro, Micael; M. L. Martins, Fernando; Ivanova, Monika Ognyanova; Mendes, RuiThe main objective of this study was to analyse the distance covered and the activity profile that players presented at the FIFA World Cup in 2010. Complementarily, the distance covered by each team within the same competition was analysed. For the purposes of this study 443 players were analysed, of which 35 were goalkeepers, 84 were external defenders, 77 were central defenders, 182 were midfielders, and 65 were forwards. Afterwards, a thorough analysis was performed on 16 teams that reached the group stage, 8 teams that achieved the round of 16, 4 teams that reached the quarter-finals, and 4 teams that qualified for the semi-finals and finals. A comparison of the mean distance covered per minute among the playing positions showed statistically significant differences (F(4,438) = 559.283; p ˂ 0.001; 2 = 0.836; Power = 1.00). A comparison of the activity time among tactical positions also resulted in statistically significant differences, specifically, low activity (F(4,183.371) = 1476.844; p ˂ 0.001; 2 = 0.742; Power = 1.00), medium activity (F(4,183.370) = 1408.106; p ˂ 0.001; 2 = 0.731; Power = 1.00), and high activity (F(4,182.861) = 1152.508; p ˂ 0.001; 2 = 0.703; Power = 1.00). Comparing the mean distance covered by teams, differences that are not statistically significant were observed (F(3,9.651) = 4.337; p ˂ 0.035; 2 = 0.206; Power = 0.541). In conclusion, the tactical positions of the players and their specific tasks influence the activity profile and physical demands during a match.
- An online tactical metrics applied to football gamePublication . Manuel Clemente, Filipe; Couceiro, Micael; M. L. Martins, Fernando; Mendes, RuiIn collective sports, the match analysis is fundamental in order to improve the quality of coaches’ intervention. Nevertheless, the generality of the systems are based on notational analysis which does not allow a deep understanding about the collective behaviour of the team. Therefore, the main goal of this study is to update and design new tactical metrics that allows an improved online knowledge about the teams’ behaviour. Tactical metrics such as the teams’ centroid, teams’ stretch index and teams’ effective play area will be presented throughout this study, validated by means of a single match experimental case study. Results suggest the potential of the herein proposed tactical metrics, providing relevant and online information to the coaches over time, thus allowing new opportunities to improve the quality of their intervention.
- Análise da ocupação espacial de futebolistas sub-12 na sub-fase de jogo 1x1 com guarda-redesPublication . Manuel Clemente, Filipe; Couceiro, Micael; M. L. Martins, Fernando; Dias, GonçaloTendo como base o modelo dos constrangimentos de Newell (1986), o presente estudo teve como objetivo estudar uma tarefa de 1x1 com guarda -redes face à ocupação do espaço pelo jogador atacante. Participaram voluntariamente 10 futebolistas (11,1 ± 0,99 anos de idade) com média de anos de prática de 1,9 (± 0,74 anos). Os resultados demonstram que, perante constrangimentos instrucionais fornecidos pelos treinadores nas situações para “arriscar”, os atacantes tendem a centralizar a sua ação em conformidade com a baliza, verificando -se o oposto quando sujeitos a instruções para conservar a bola, ou seja, dispersando a ação pelo espaço de prática. Os dados obtidos mostram que a manipulação de constrangimentos instrucionais na díade atacante -defensor em futebolistas é relevante confirmando, igualmente, a pertinência da utilização de heat maps para a análise da ocupação espacial dos jogadores
- Análise de jogo no futebol : métricas de avaliação do comportamento coletivoPublication . Manuel Clemente, Filipe; Couceiro, Micael; M. L. Martins, Fernando; Figueiredo, António J.; Mendes, RuiO jogo de futebol, como realidade complexa, necessita de uma interpretação do comportamento coletivo da equipa. Assim, o presente trabalho objetivou apresentar 4 métricas de avaliação coletiva baseadas na relação espácio-temporal, procurando identificar diferenças nos comportamentos coletivos nos momentos com e sem posse de bola. Para o efeito, analisou-se um jogo de futebol de sete do escalão de formação sub-14. Os resultados evidenciaram diferenças significativas entre os momentos com e sem posse de bola no que se refere ao espaço ocupado pelas equipas A (F(1, 1506)= 8.31, p= 0.004, η²= 0.005, Power= 0.82) e B (F(1, 1506)= 37.66, p= 0.001, η²= 0.024, Power= 1.00), às triangulações efetivas entre jogadores nas equipas A (F(1, 1506)= 1343.89, p= 0.001, η²= 0.472, Power= 1.000) e B (F(1, 1506)= 968.50, p= 0.001, η²= 0.391; Power= 1.00) e à progressão do centroid nas equipas A (F(1. 1506)= 11.79, p= 0.001, η²= 0.008, Power= 0.93) e B (F(1, 1506)= 9.43, p= 0.001, η²= 0.006, Power= 0.87). Conclui-se com o presente trabalho que as métricas de avaliação coletiva possibilitam uma identificação de relações espácio-temporais entre jogadores, identificando uma expansão maior das equipas na situação com posse de bola, bem como, o avanço do ponto médio da equipa.
- Analysis and parameter adjustment of the RDPSO towards an understanding of robotic network dynamic partitioning based on Darwin's theoryPublication . Couceiro, Micael; M. L. Martins, Fernando; Rocha, Rui P.; Ferreira, N. M. FonsecaAlthough the well-known Particle Swarm Optimization (PSO) algorithm has been first introduced more than a decade ago, there is a lack of methods to tune the algorithm parameters in order to improve its performance. An extension of the PSO to multi-robot foraging has been recently proposed and denoted as Robotic Darwinian PSO (RDPSO), wherein sociobiological mechanisms are used to enhance the ability to escape from local optima. This novel swarm algorithm benefits from using multiple smaller networks (one for each swarm), thus decreasing the number of nodes (i.e., robots) and the amount of information exchanged among robots belonging to the same sub-network. This article presents a formal analysis of RDPSO in order to better understand the relationship between the algorithm’s parameters and its convergence. Therefore, a stability analysis and parameter adjustment based on acceleration and deceleration states of the robots is performed. These parameters are evaluated in a population of physical mobile robots for different values of communication range. Experimental results show that, for the proposed mission and parameter tuning, the algorithm con-verges to the global optimum in approximately 90% of the experiments regardless on the number of robots and the communication range.
- Analysis of football player’s motion in view of fractional calculusPublication . Couceiro, Micael; Manuel Clemente, Filipe; M. L. Martins, FernandoAccurately retrieving the position of football players over time may lay the foundations for a whole series of possible new performance metrics for coaches and assistants. Despite the recent developments of automatic tracking systems, the misclassification problem (i.e., misleading a given player by another) still exists and requires human operators as final evaluators. This paper proposes an adaptive fractional calculus (FC) approach to improve the accuracy of tracking methods by estimating the position of players based on their trajectory so far. One half-time of an official football match was used to evaluate the accuracy of the proposed approach under different sampling periods of 250, 500 and 1000 ms. Moreover, the performance of the FC approach was compared with position-based and velocity-based methods. The experimental evaluation shows that the FC method presents a high classification accuracy for small sampling periods. Such results suggest that fractional dynamics may fit the trajectory of football players, thus being useful to increase the autonomy of tracking systems.
- Autimatic tools of match analysis : inspecting soccer team's dispersionPublication . Manuel Clemente, Filipe; Couceiro, Micael; M. L. Martins, Fernando; Korgaokar, AjitThe contracting-expanding soccer teams' relationship is one of the most important dynamic behaviors of the game. Therefore, a soccer game was analyzed using the centroid and stretch index method, while recording the team's ball possession status (with or without ball possession). The correlation test suggest an inverse relationship between opposing teams (r _(1508)=- 0.054) during all game. When considering ball possession by the teams, the results of the stretch index confirm that there are statistical differences with a small effect between the moments with and without possession of the ball for team B (F_(1; 1506)=22.777; p-value≤0.001; η^2=0.015; Power=0.998). Therefore, it was possible to confirm that the contracting -expanding relationship is an intrinsic behaviour of a soccer game in relation to ball possession.
- Developing a tactical metric to estimate the defensive area of soccer teams : the defensive play areaPublication . Manuel Clemente, Filipe; M. L. Martins, Fernando; Couceiro, Micael; Mendes, Rui; Figueiredo, António J.This study proposes a computational method to inspect the tactical position of players during the match and a new metric to analyse the defensive pressure made by a soccer team. These metrics only require Cartesian information about the players’ positions on the field. As a case study, three matches played by the same professional soccer team were considered, including variables computed for the half of the match (first half vs second half) and the final score of the game for an analysis of variance of tactical performance, trying to identify the influence of such variables on the collective organisation. The data were collected at 1 Hz and from this process, 9218 instances of useful time were collected. The results revealed that the different kinds of final scores had significant effects on the tactical performance. The comparison between two halves of the match revealed significant differences with a small effect size on tactical performance. In summary, this study showed that these new tactical metrics can be a computational option to increase a coaches’ knowledge about the defensive organisation of soccer teams, giving them the possibility to augment their own perception with metrics that can provide specific information.
- Dispositivo de escoamento aerodinâmico induzido para análise do desempenho do serviço de ténisPublication . Cabral Mendes, Pedro; Mendes, Rui; Coelho-e-Silva, M. ou Coelho-e-Silva, M.J. ou Coelho-Silva, M ou Silva, M.; Luz, João Miguel Almeida; Dias, Gonçalo; Couceiro, MicaelEste trabalho teve como objetivo desenvolver um dispositivo de produção de um Escoamento Aerodinâmico Induzido (EAI) capaz de simular a constrição ambiental e vento lateral, em contexto experimental de análise ao primeiro serviço de tênis. Para tal, estudou-se o comportamento da bola de tênis sob o efeito de um EAI no túnel de vento e analisou-se (3D) o lançamento da bola no primeiro serviço plano de 12 jogadores de tênis experientes. Concebeu-se um dispositivo composto por um ventilador industrial ajustável em altura e em profundidade às caraterísticas morfológicas e técnicas do tenista. O caudal de EAI é estável e monitorizável através de um variador de velocidade. Conclui-se que as três “velocidades de vento” selecionadas, constrangem o lançamento da bola (simulado por uma máquina) no eixo dos x (lateral), tornando o dispositivo capaz de perturbar a execução motora do serviço de tênis, recriando uma constrição ambiental relevante para a modalidade.