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Expertise en patinage en hockey sur glace : effet des contraintes de tâche / Forward ice-hockey skating expertise : effect of task constraints manipulationMell, Florian 20 October 2017 (has links)
Nos recherches s'inscrivent dans le cadre théorique Ecological Dynamics du contrôle moteur, considérant que le comportement moteur, émerge, persiste et se réorganise en fonction des interactions de l’individu avec un ensemble de contraintes. Sur cette base, nous explorons les indices permettant de rendre compte de l’adaptation motrice du hockeyeur à diverses contraintes afin d’analyser l’expertise. À ce titre, nous avons conduit nos recherches en deux temps : i) une analyse qualitative d’entretiens semi-directifs, et ii) une analyse des paramètres superficiels (cinématique et cinétique) et profonds (coordination) du mouvement de patinage avant. À travers l’analyse de dix entretiens d’entraîneurs experts, nous avons observé que les entraîneurs faisaient appel à des connaissances « opératives » organisées en trois catégories (la posture du hockeyeur, l’action des bras, la cinématique des membres inférieurs). Cette étude nous a permis d’enrichir la connaissance des indicateurs de performances du patinage expert et de guider la conception d’un protocole expérimental représentatif du contexte écologique de pratique. La seconde partie du travail consiste en une analyse des paramètres profonds et superficiels du mouvement sous l’effet de manipulation de contraintes de tâche lors d’un sprint sur 20m. Les résultats révèlent une forte stabilité du pattern expert au niveau de l’ensemble des paramètres superficiels, ainsi qu’un mode de coordination en rattrapé et une symétrie entre les membres inférieurs, lorsque l’activité du joueur n’est pas contrainte par la conduite du palet. Cette dernière induit une flexibilité du comportement caractéristique de l’adaptabilité de l’expert. / Based on the theoretical framework of Ecological Dynamics, the aim of this PhD thesis is to analyse the motor behaviour of expert ice-hockey players in relation to a set of interacting constraints. Based on this theoretical framework, our research investigates the performance indicators in order to understand how ice-hockey expert players’ behaviour emerges, persists and is reorganised when the individuals interacts with a set of constraints. We conduced our work in two stages: i) a qualitative research analysing semi-structured interviews of ice-hockey expert coaches and ii) a biomechanics analysis of forward skating. Analysing 10 ice-hockey expert coaches interviews reveals that coaches used ‘operative knowledge’ organized into three main categories (arm movement, lower limb kinematics and posture). This study allowed us to improve our understanding of performance indicators of expert forward skating. It also helped us to design a more representative biomechanics research protocol of forward skating. The second part of this thesis consists of an analysis of low-order and high-order parameters under task constraints manipulation during 20m forward sprints. Our results showed a strong stability of forward skating pattern at the low-order parameters scale as well as a stable catch-up coordination between the two feet and a stable symmetry in the lower limbs movement coordination when expert player weren’t under puck dribbling situation. When they had to run with the puck, experts’ behaviour revealed a significative variability in skating pattern organisation suggesting flexibility of experts’ behaviour in order to improve their adaptability to tasks constraints.
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The Effect of Temporal Pressure on Responsiveness and Gaze Patterns during a Dynamic, Gap Passability Navigation TaskAlt, Jeromy January 2022 (has links)
No description available.
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O efeito da experiência, do conhecimento e da habilidade na tomada de decisão do passe do futsal a partir das relações interpessoais angulares / The effect of experience, knowledge and skill on decision-making futsal pass from the angular interpersonal relationshipsSilva, Silvia Leticia da 15 December 2014 (has links)
A tomada de decisão diz respeito a um componente essencial para o desempenho de inúmeras habilidades motoras, principalmente aquelas que envolvem julgamentos e escolhas. Duas correntes teóricas se destacam nesse âmbito: uma, com foco nos níveis de experiência e conhecimento dos indivíduos e, outra, na percepção de variáveis físicas que refletem a coordenação interpessoal. No presente estudo ambas foram consideradas conjuntamente. Investigou-se como indivíduos de diferentes níveis de experiência, conhecimento e habilidade decidiam sobre o passe de bola com base em relações interpessoais angulares. Ângulo foi escolhido como variável coletiva em razão de capturar as relações interpessoais em situações de passes e interceptação de passes. Foram filmados dois jogos de futsal com jogadores experientes e inexperientes entre 13 e 14 anos de idade. As relações interpessoais angulares foram compostas por: ângulo A, interação de vetores ligando o portador da bola com seu marcador e seu companheiro de time; e, ângulo B, interação de vetores ligando o portador da bola com seu companheiro de time e o marcador dele. Essas relações angulares também foram consideradas em relação à taxa de mudança com base em velocidade e variabilidade. Todas as medidas foram calculadas com base nos deslocamentos dos jogadores adquiridos por meio do software TACTO, em relação às coordenadas x e y, numa frequência de 25 Hz. Os dados foram analisados através do teste U de Mann-Whitney, considerando-se o nível de significância de p<=0,05. Os resultados obtidos referentes aos níveis de experiência e de conhecimento não revelaram diferenças significativas em nenhuma das variáveis angulares. Já com relação ao nível de habilidade, diferenças significativas foram encontradas somente para a velocidade angular (B). No que diz respeito à efetividade do passe, os resultados revelaram que independente dos níveis de experiência, conhecimento e habilidade, os passes efetivos foram realizados com base no ângulo (B). Os resultados permitem concluir que os jogadores, independente dos níveis de experiência e de conhecimento, utilizaram as mesmas relações interpessoais angulares para realização do passe, e que o ângulo (B) foi aquele que influenciou na eficiência do passe / The decision-making is an essential component for the performance of a number of motor skills, meanly for those that involve judgments and choices. Two theoretical perspectives highlight in this context: one focusing on the levels of experience and knowledge of individuals, and another, on the perception of physical variables that reflect the interaction between individuals and their environments. In the present study both of them were considered together. We investigated how individuals with different levels of experience, knowledge and skill decided on the pass of the ball based on angular interpersonal interactions. The angle was chosen as collective variable due it be able to capture the interpersonal relationships in situations of passing and intercepting of passing. Two futsal games were filmed with experienced and inexperienced players between 13 and 14 years old. The angular interpersonal relationships were: angle A, passing vector angle to the ball carriernearest defender\'s vector; and angle B, vector angle to the ball carrier-teammate\'s nearest defender\'s vector. These angular relationships were also considered in relation to their rate of change based on velocity and variability. All measures were calculated based on the displacements of the players relative to the x and y coordinates, which were acquired through the TACTO software in a frequency of 25 Hz. The data have been analysed by the U teste of Mann-Whitney considering the level of significance p<=0.05. The results obtained related to the levels of experience and knowledge haven´t revealed significant differences in none of the angular variables. But considering the level of skill, significant differences have been found only towards the angular velocity (B). Regarding the effectiveness of the pass the results showed that despite the levels of experience, knowledge and skill, the effective pass been carried out based on angle (B). The results allow concluding that players, regardless of level of experience and knowledge, used the same angular interpersonal relationships for performing the pass. In addition, that the efficiency of passing was influenced by the angle (B)
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O efeito da experiência, do conhecimento e da habilidade na tomada de decisão do passe do futsal a partir das relações interpessoais angulares / The effect of experience, knowledge and skill on decision-making futsal pass from the angular interpersonal relationshipsSilvia Leticia da Silva 15 December 2014 (has links)
A tomada de decisão diz respeito a um componente essencial para o desempenho de inúmeras habilidades motoras, principalmente aquelas que envolvem julgamentos e escolhas. Duas correntes teóricas se destacam nesse âmbito: uma, com foco nos níveis de experiência e conhecimento dos indivíduos e, outra, na percepção de variáveis físicas que refletem a coordenação interpessoal. No presente estudo ambas foram consideradas conjuntamente. Investigou-se como indivíduos de diferentes níveis de experiência, conhecimento e habilidade decidiam sobre o passe de bola com base em relações interpessoais angulares. Ângulo foi escolhido como variável coletiva em razão de capturar as relações interpessoais em situações de passes e interceptação de passes. Foram filmados dois jogos de futsal com jogadores experientes e inexperientes entre 13 e 14 anos de idade. As relações interpessoais angulares foram compostas por: ângulo A, interação de vetores ligando o portador da bola com seu marcador e seu companheiro de time; e, ângulo B, interação de vetores ligando o portador da bola com seu companheiro de time e o marcador dele. Essas relações angulares também foram consideradas em relação à taxa de mudança com base em velocidade e variabilidade. Todas as medidas foram calculadas com base nos deslocamentos dos jogadores adquiridos por meio do software TACTO, em relação às coordenadas x e y, numa frequência de 25 Hz. Os dados foram analisados através do teste U de Mann-Whitney, considerando-se o nível de significância de p<=0,05. Os resultados obtidos referentes aos níveis de experiência e de conhecimento não revelaram diferenças significativas em nenhuma das variáveis angulares. Já com relação ao nível de habilidade, diferenças significativas foram encontradas somente para a velocidade angular (B). No que diz respeito à efetividade do passe, os resultados revelaram que independente dos níveis de experiência, conhecimento e habilidade, os passes efetivos foram realizados com base no ângulo (B). Os resultados permitem concluir que os jogadores, independente dos níveis de experiência e de conhecimento, utilizaram as mesmas relações interpessoais angulares para realização do passe, e que o ângulo (B) foi aquele que influenciou na eficiência do passe / The decision-making is an essential component for the performance of a number of motor skills, meanly for those that involve judgments and choices. Two theoretical perspectives highlight in this context: one focusing on the levels of experience and knowledge of individuals, and another, on the perception of physical variables that reflect the interaction between individuals and their environments. In the present study both of them were considered together. We investigated how individuals with different levels of experience, knowledge and skill decided on the pass of the ball based on angular interpersonal interactions. The angle was chosen as collective variable due it be able to capture the interpersonal relationships in situations of passing and intercepting of passing. Two futsal games were filmed with experienced and inexperienced players between 13 and 14 years old. The angular interpersonal relationships were: angle A, passing vector angle to the ball carriernearest defender\'s vector; and angle B, vector angle to the ball carrier-teammate\'s nearest defender\'s vector. These angular relationships were also considered in relation to their rate of change based on velocity and variability. All measures were calculated based on the displacements of the players relative to the x and y coordinates, which were acquired through the TACTO software in a frequency of 25 Hz. The data have been analysed by the U teste of Mann-Whitney considering the level of significance p<=0.05. The results obtained related to the levels of experience and knowledge haven´t revealed significant differences in none of the angular variables. But considering the level of skill, significant differences have been found only towards the angular velocity (B). Regarding the effectiveness of the pass the results showed that despite the levels of experience, knowledge and skill, the effective pass been carried out based on angle (B). The results allow concluding that players, regardless of level of experience and knowledge, used the same angular interpersonal relationships for performing the pass. In addition, that the efficiency of passing was influenced by the angle (B)
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Perception et action en natation : effets de l'environnement aquatique et de la vitesse de mouvement sur la dynamique des coordinations / Perception and action in swimming : effects of aquatic environment and speed on coordination dynamicsGuignard, Brice 17 November 2017 (has links)
L’objectif de ce travail est de caractériser la dynamique des coordinations de nageurs experts en fonction de la manipulation de contraintes de tâche (vitesse de nage) et d’environnement (écoulement). Les coordinations intra- et inter-membre (bras vs. bras et bras vs. jambes) sont déterminées à l’aide de centrales inertielles positionnées sur des nageurs experts, réalisant deux tâches de scanning dans une piscine et un bassin à contre-courant. Nous caractérisons l’effet de l’environnement en comparant la coordination intra-bras à la même vitesse de nage dans les deux bassins, puis la dynamique de cette même coordination et de la coordination bras vs. bras lors d’une tâche impliquant huit vitesses. Finalement, la dynamique des coordinations bras vs. jambes est analysée, tout comme l’asymétrie droite/gauche.Nos résultats montrent que le flume canalise l’émergence de comportements fonctionnels, en particulier en faisant décroître la durée de la phase de glisse du fait de l’écoulement dynamique de la masse d’eau. L’augmentation de la vitesse de nage montre de plus larges implications des jambes dans la propulsion. La nage dans le flume conduit à une force de couplage plus faible entre les bras et les jambes et de plus larges asymétries droite/gauche. Les nageurs experts sont donc capables d’adapter leurs coordinations intra- et inter-segmentaires et peuvent transiter entre différents patrons en fonction des contraintes auxquelles ils font face. Ainsi, des périodes de stabilité sont couplées avec des périodes de flexibilité comportementales, exemplifiant leur habileté pour réaliser le but de la tâche en interagissant fonctionnellement avec l’environnement aquatique. / The aim of this thesis is to investigate the coordination dynamics of expert swimmers as a function of both task (swimming speed) and environmental (fluid flow) constraints manipulation. The intra - and inter-segmental coordination (arms vs. arms and arms vs. legs) are assessed by inertial measurement units positioned on expert swimmers swimming two separated scanning tasks in a flume and in a pool. We investigate the effect of aquatic flow by comparing the upper limb coordination when the swimmers swim at a similar speed in pool and flume, then, the upper limb coordination dynamics during a scanning procedure where speed is increased through eight steps. Finally, the arms vs. legs coordination dynamics and the right/left asymmetry were analyzed.Our findings demonstrate that flume is channeling the emergence of functional expert swimmers’ movement patterns, in particular the decrease of glide phase duration related to the moving body of water. The increase of speed reveals larger implications of the lower limbs in the propulsion. Flume swimming leads to lower coupling strength between oscillators and higher asymmetries in the flume. Our findings thus demonstrated that experts are able to adapt their coordination patterns at different levels (intra-segmental of the upper limbs / inter-limb i.e., arms vs. legs) and by transiting between different patterns according to the constraints encountered. Thus swimmers exhibit both periods of behavioral stability and periods of adaptive flexibility, showing their ability to achieve the task-goal by functional interaction with the aquatic environment.
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The Ecological Dynamics of a Coastal LagoonNandi, Nandi 17 February 2015 (has links) (PDF)
A coastal lagoon is a landform that is influenced by natural processes and human activities. All human activities at the upstream, particularly agriculture and cultivation bring soil, waste, and other materials to the downstream area through the river drains into the lagoon. Even though its position is inland of water bodies, the lagoon is still affected by waves and winds from the sea. Additionally, coastal lagoon will be the depository place for sedimentation from the upland area. Segara Anakan (SA), which is located in Indonesia, is an example of a coastal lagoon area, which has a unique biophysical characteristic. The region has a great natural ability to ensure the sustainability of the interrelationships between terrestrial, estuarine and marine ecosystems in harmony and balance as a habitat for flora and fauna. The region is an area of migration of various types of protected animals and it is a place of breeding for diverse species of the shrimp and fish, which have a highly economical value. Segara Anakan lagoon (SAL), currently experiencing acceleration narrowed on its area due to a very intensive sedimentation from the mainland.
The research aims to answer the question of how ecological dynamic occurs in the SAL area due to sedimentation. Achieving the objectives of this study required examining the morphology and land use changes with multitemporal remote sensing approaches. While, to assess the role of community participation and planning management strategies is using qualitative descriptive methods and SWOT analyze.
The using of multitemporal remote sensing Landsat images is possible to analyze the morphological and land use changes with different time and sensors. These Landsat has image accuracy about 92.66%. It can be used for image interpretations resulting 13 classes of land use. The morphodynamics of SAL indicated by the changes of area of lagoon and accreted land and also the distance of coastlines during the periods 1979-2013. In addition, the land use or land cover also changes during that time. The bigger portions of land use changes are in the tropical and mangrove\'s forests.
There are distinctive forms of participation in conservation efforts. The upstream community involvement in conservation tends to be different participating in the way of ideas, money, materials, properties, skills and expertise or social activities. In addition, the community at downstream area has a sufficiently high level of participation in environmental conservation. There are also strong relationships between the level of education and level of income and basic knowledge in conservation with the participation of SA conservation.
The ecological dynamics of the SAL area are described with a historical time line. It is divided into three time periods: the 1970s - 1980s, the 1990s and from 2000 onwards. Each of these has occurrences that can lead to changes in the environment.
The implementation of appropriate conservation technique can reduce the sedimentation rate. Hence, the synergic coordination measures between upstream and downstream regions are necessary in the future. Increasing community awareness and participation in the conservation by improving educational sector, providing information, and applying sustainable development land use are the ways to match human activities with the temporal and spatial dynamics of the coastal resources.
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Ressources naturelles et développement dans le monde tropical : les contradictions entre dynamiques écologiques, reproduction sociale et ordre économique international / Natural resources and development in the tropical world : the contradictions between socio-ecological dynamics, social reproduction and the international economic orderSchmitt, Boris 02 December 2013 (has links)
Les ressources naturelles sont au cœur de dynamiques contradictoires. Alors qu'elles sont essentielles à la reproduction des sociétés et du vivant, l'organisation actuelle de l'économie mondiale tend à les subordonner principalement à des logiques d'accumulation. Outre que ces dernières ne prennent pas suffisamment en compte les limites physiques au sein desquelles l'humanité évolue, elles entraînent à diverses échelles des inégalités problématiques sur les plans social et écologique. L'ordre économique international actuel tend en effet à générer des phénomènes d'échange écologique inégal qui nuisent au développement des pays producteurs et exportateurs de matières premières, ainsi qu'aux populations et écosystèmes les plus vulnérables en leur sein. Le monde tropical est exemplaire de telles contradictions, concentrant parmi les plus importantes ressources de la biosphère – notamment en matière de biodiversité – ainsi que des milieux socio-écologiques particulièrement fragilisés. Face à des visions et logiques économicistes d'exploitation des ressources, qui s'inscrivent dans la longue durée historique, et trouvent des relais dans les structures juridico-politiques du système économique mondial, il importe de repenser le concept même de ressource naturelle. Il s'agit en effet de redonner toute leur place aux dimensions sociales et écologiques dans les processus de gestion et d'exploitation des ressources. Cela implique une réflexion sur les valeurs qui guident les interactions avec la nature et les relations économiques internationales, afin que la solidarité, la complémentarité et la justice deviennent des priorités. / Natural resources are in the midst of contradictory dynamics. While they are essential to the reproduction of societies and life, actual organization of the world economy subordinates them to logics of accumulation. In addition to the fact that these logics don't take into account (consider) the physical limits inside of which humanity evolves, they induce problematic socio-ecological inequalities at different scales. Indeed, actual international economic order tends to generate ecologically unequal exchanges, which disrupt the development of primary exporting countries and threaten the most vulnerable populations and ecosystems inside of them.Tropics are the typical context in which such contradictions develop themselves. Actually, this part of the world concentrates some of the most important resources for the biosphere – such as biodiversity – but also highly fragilized socio-ecological environments.To confront economistic views and logics of resources exploitation, which are the product of the longue durée, and find support in the juridical and political structures of the world economic system, it is critical to rethink the very concept of natural resources. Social and ecological dimensions should be put back at the heart of natural resources management and exploitation process. Such an approach necessitates thinking about the values that guide interactions with nature and international economic relations, so that solidarity, complementarity and justice become priorities.
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The Ecological Dynamics of a Coastal Lagoon: A Study of the Morphodynamics, Land Use Change, Community Participation, and Spatial Planning of the Segara Anakan Lagoon in IndonesiaNandi, Nandi 04 February 2015 (has links)
A coastal lagoon is a landform that is influenced by natural processes and human activities. All human activities at the upstream, particularly agriculture and cultivation bring soil, waste, and other materials to the downstream area through the river drains into the lagoon. Even though its position is inland of water bodies, the lagoon is still affected by waves and winds from the sea. Additionally, coastal lagoon will be the depository place for sedimentation from the upland area. Segara Anakan (SA), which is located in Indonesia, is an example of a coastal lagoon area, which has a unique biophysical characteristic. The region has a great natural ability to ensure the sustainability of the interrelationships between terrestrial, estuarine and marine ecosystems in harmony and balance as a habitat for flora and fauna. The region is an area of migration of various types of protected animals and it is a place of breeding for diverse species of the shrimp and fish, which have a highly economical value. Segara Anakan lagoon (SAL), currently experiencing acceleration narrowed on its area due to a very intensive sedimentation from the mainland.
The research aims to answer the question of how ecological dynamic occurs in the SAL area due to sedimentation. Achieving the objectives of this study required examining the morphology and land use changes with multitemporal remote sensing approaches. While, to assess the role of community participation and planning management strategies is using qualitative descriptive methods and SWOT analyze.
The using of multitemporal remote sensing Landsat images is possible to analyze the morphological and land use changes with different time and sensors. These Landsat has image accuracy about 92.66%. It can be used for image interpretations resulting 13 classes of land use. The morphodynamics of SAL indicated by the changes of area of lagoon and accreted land and also the distance of coastlines during the periods 1979-2013. In addition, the land use or land cover also changes during that time. The bigger portions of land use changes are in the tropical and mangrove\''s forests.
There are distinctive forms of participation in conservation efforts. The upstream community involvement in conservation tends to be different participating in the way of ideas, money, materials, properties, skills and expertise or social activities. In addition, the community at downstream area has a sufficiently high level of participation in environmental conservation. There are also strong relationships between the level of education and level of income and basic knowledge in conservation with the participation of SA conservation.
The ecological dynamics of the SAL area are described with a historical time line. It is divided into three time periods: the 1970s - 1980s, the 1990s and from 2000 onwards. Each of these has occurrences that can lead to changes in the environment.
The implementation of appropriate conservation technique can reduce the sedimentation rate. Hence, the synergic coordination measures between upstream and downstream regions are necessary in the future. Increasing community awareness and participation in the conservation by improving educational sector, providing information, and applying sustainable development land use are the ways to match human activities with the temporal and spatial dynamics of the coastal resources.
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