Introduction: A realtime weightlifting automatic barbell trajectory extraction algorithm was proposed in this paper. We utilize the color and motion characteristics of the barbell to extract from the ...video sequence and further implement a computer-aided weightlifting training system by considering the barbell trajectory. Our aim was to create a new computer-aided training system which can utilize in a real competition and feedback analysis result to the coach in realtime. This system can effectively decrease the cost of the kinematic analysis which needs manual marker and lab environmental. Methods: Spatial and temporal of the video sequence are both considering to find the coordinate of barbell in a frame and further connect the coordinates as the trajectory. The trajectory of the barbell was utilized in our computer-aided training system and evaluated the performance of the lifter. Results: 2013 Taiwan Weightlifting Universidad Game was utilized to verify our proposed algorithm. The video sequence was captu
Les cœurs de réacteur à neutrons rapides refroidi au sodium (RNR-Na ) sont constitués d’assemblages combustibles disposés selon un réseau hexagonal régulier, compact en régime de fonctionnement ...nominal.Sous l’effet de l’irradiation et de la température, les assemblages sont amenés à se déformer axialement et radialement.Les objectifs de cette thèse sont la compréhension des phénomènes neutroniques intervenant lors d’une telle déformation du cœur, l’impact sur la conception ainsi que la mise au point de schémas de calcul neutroniques déterministes innovants aptes à en évaluer l’amplitude.La première partie de ces travaux est dédiée au développement d’une modélisation analytique des causes de variations de réactivité lors de la déformation du cœur. Cette analyse a permis d’identifier à la fois les causes de ces variations de réactivité et l’impact du déplacement des assemblages en fonction de leurs directions et de leurs positions dans le cœur.Un premier schéma neutronique basé sur la méthode de projection de maillage a été conçu et développé à l’aide des codes ERANOS (BISTRO, H3D et VARIANT) et du solveur SNATCH Le deuxième schéma conçu se base sur la transformation géométrique du maillage de calcul : le maillage est modifié en fonction du champ des déformations des assemblages. Cette fonctionnalité a été implémentée pour le solveur SNATCH, initialement prévu pour la résolution de l’équation de Boltzmann pour de mailles régulières.Enfin un modèle itératif basé sur la méthode de projection de maillage a été mis en place afin de déterminer les champs de déformations les plus réactifs en fonction de l’énergie mécanique fournie au cœur dans sa configuration nominale.
The fuel assemblies of SFR cores (sodium fast reactors) are normally arranged in hexagonal regular lattices, whose compactness is ensured in nominal operating conditions by thermal expansion of assemblies pads disposed on the six assembly wrapper faces.During the reactor operations, thermal expansion phenomena and irradiation creep phenomena occur and they cause the fuel assemblies to bow and to deform both radially and axially.The main goal of this PhD is the understanding of the neutronic aspects and phenomena occurring in case of core and lattice deformations, as much as the design and implementation of deterministic neutronic calculation schemes and methods in order to evaluate the consequences for the core design activities and the safety analysis.The first part of this work is focused on the development of an analytical model with the purpose to identify the neutronic phenomena that are the main contributors to the reactivity changes induced by lattice and core deformations.A first scheme based on the spatial mesh projection method has been conceived and implemented for the ERANOS codes (BISTRO, H3D and VARIANT) and to the SNATCH solver.The second calculation scheme propose is based on mesh deformation: the computing mesh is deformed as a function of the assembly displacement field. This methodology has been implemented for the solver SNATCH, which normally allows the Boltzmann equation to be solved for a regular mesh. Finally, an iterative method has been developed in order to fulfill an a-priori estimation of the maximal reactivity insertion as a function of the postulated mechanical energy provided to the core, as much as the deformation causing it.
Various crimes have been steadily increasing and many people feel uneasy about public safety. Especially, the number of snatch occurrence in Osaka has been the top in Japan for the last 31 years, and ...it is serious problem. This study aims to research relationship between visibility and occurrence of snatch by quantifying the visibility. At first, from relationship among occurrence of snatch, population data, land-use data, and illuminance data, 24 wards in Osaka city were classified into 4 groups. In Sumiyoshi ward, belonging residential area group, relationship of occurrence of snatch was studied. From the study, the rate of occurrence of snatch is relatively lower in the area where distance of visible road is from 50m to 100m comparing the area where the distance is longer or shorter in both.
본 연구는 복/배근력의 균형적 발달비가 역도 인상기술에 어떠한 영향을 미치는 지를 알아보기 위해 복/배근력의 균형비가 1:1.33 이하의 불균형을 보인 국가대표 남자 역도선수 4명을 대상으로 복근과 배근 강화훈련을 5개월간 처치하고, 처치전 동작은 6월 선수권대회, 처치후 동작은 10월 전국선수권 대회를 통해 기술변화 양상을 비교분석 하였다. 분석은 2D ...DLT 방법을 활용하였고 이 연구를 통하여 복근과 배근 강화 훈련을 매일 5개월 간 실시하여 나타난 복/배근력 균형비는 14-53%의 균형비 증가가 있는 것으로 나타났다. 선수 A,B,D는 복근력과 복/배근력 비율이 훈련 프로그램으로 향상되었고, 풀 구간에서 운동수행 시간이 줄어들었고, 이동거리에서 출발구간, 풀 구간, 앉아받기 구간 모두 짧게 나타났으며, 선수 C는 복근력과 복/배근력의 비율이 훈련 프로그램으로 향상되었고, 풀 구간에서 최대속도가 줄어들었고, 이동거리에서 출발구간, 풀 구간, 앉아받기 구간 모두 짧게 나타났다. 복근과 배근 강화훈련으로 효율적인 동작은 풀 구간에서 짧고 빠르게 바벨을 이동시키는 것으로 나타났으며 이는 국가대표 남자선수 4명 모두 3-15Cm 정도 풀 구간 바벨이동거리가 짧아지게 하는데 기여하였다.
The Purpose of this study was to investigate snatch technique enhancement effect by 5 months ABS & Back training. We analysed Korea elite weightlifting championship in June, 2003 before ABS & Back training and analysed Korea weightlifting competetion in October, 2003 after ABS/Back training. They are videotaped on digital camera with the frame rate being 30Hz. This data was reduced to 2D coordinates using 2D DLT method. It was conclusions that; ① The balance rate of Abdominal muscles/Back muscle enhanced 14-53% by 5 months ABS/Back training for four subjects. ② Subject A, B, D reduced pull phase time, also movement distance reduce in start phase, pull phase, lock out phase. ③ Subject C reduced maximal velocity in pull phase, and movement distance reduce in start phase, pull phase, lock out phase. ④ Pull phase time reduced by ABS/Back trainning. and reduce barbell movement distance about 3-15cm for four subjects.
The paper presents a comparative analysis of the data obtained from the vertical trajectory of the bar during weightlifting in the snatch mode, these amateur athletes will be compared to an elite ...athlete in weightlifting, in order to obtain velocities and accelerations for the evaluation of the technique used in each phase. The Lagrange interpolation method was used to obtain a mathematical representation a function of time describing the trajectory of the bar during the uprising in the snatch mode, to thereby obtain the speed and acceleration during the lifting of the bar at every phase.
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