The Experts below are selected from a list of 450 Experts worldwide ranked by ideXlab platform
Kamiar Aminian - One of the best experts on this subject based on the ideXlab platform.
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Orientation of body segments in Ski Jumps using wearable sensors: Analysis of relevant parameters during stable flight phase
2010Co-Authors: Julien Chardonnens, Julien Favre, Florian Cuendet, Gérald Gremion, Kamiar AminianAbstract:Biomechanics analysis of the Ski jump is highly required. Some parameters and their interrelations have been reported in previous research studies limited to few athletes. The generalization of these parameters to athletes of various levels and under training conditions should be assessed, since they have the potential to be used for daily evaluation. This study proposed a new 3D approach based on inertial sensors to evaluate relevant kinematic and aerodynamic parameters of stable flight phase. The proposed wearable system can easily be used for daily training. Aerodynamic forces and body segments 3D angles were extracted during the stable flight phase of 86 Jumps. Then, their correlations with respect to distance as well as their interrelations were analyzed. Their combination expressed 55% of the total distance variance.
Casa Tipán, Edwin Patricio - One of the best experts on this subject based on the ideXlab platform.
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Estudio en modelo del cuenco de socavación al pie de los vertederos de excesos en la Presa Toachi, Proyecto Hidroeléctrico Toachi - Pilatón.
Quito: UCE., 2012Co-Authors: Casa Tipán, Edwin PatricioAbstract:Los chorros que despegan desde saltos en esquí e impactan en el cuenco amortiguador caen a cierta distancia de la presa, estos producen fosos de socavación existiendo la probabilidad de que las estructuras de descarga y las márgenes del cuenco amortiguador sean afectadas. Los modelos hidráulicos son muy importantes para el diseño de la geometría del cuenco disipador de energía. El presente trabajo de investigación trata del análisis de la evolución temporal del foso socavado en un lecho de fondo móvil que contiene grava, esta se encuentra ubicado al pie de los vertederos de excesos de la presa Toachi, se realiza un análisis cualitativo del foso socavado producido para cinco diferentes estructuras de caída (deflectores) presentes en el salto en esquí. Para todas las alternativas ensayadas en la socavación resultante se observa que el material es arrastrado hasta cubrir el umbral, el mismo que restringe el desarrollo longitudinal del foso. Con la operación simultánea de los vertederos de excesos usando los deflectores discontinuos y contracción, se observa la incidencia negativa del foso en las márgenes del cuenco amortiguador.The jets taking off from Ski Jumps and impact in the stilling basin fall some distance from the dam; these scour pits produce the probability exists that discharge structures and stilling basin margins are affected. Hydraulic models are very important for the design of the geometry of the stilling basin. This work presents the analysis of the temporal evolution of the pit undermined in a bed of gravel containing mobile background, this is located at the foot of spillway excess Toachi dam, is performed a qualitative analysis of the pit produced undermined for five different drop structures (buckets) present in the Ski jump. For all alternatives tested in the resultant scour shows that the material is drawn to cover the doorway, restricting the same longitudinal development of the pit. With the simultaneous operation of spillways excess using discontinuous buckets and contraction seen the negative impact of the pit in the stilling basin margins
Dávila Rodríguez, Dimitri David - One of the best experts on this subject based on the ideXlab platform.
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Estudio experimental sobre el alcance y la dirección del chorro a la salida de los vertederos de excesos de la Presa Toachi, Proyecto Toachi Pilatón.
Quito: UCE., 2013Co-Authors: Dávila Rodríguez, Dimitri DavidAbstract:El presente trabajo de investigación tiene como objetivo principal el análisis de la dirección, alcance y forma del chorro proyectado por el vertedero de excesos derecho de la presa Toachi, Proyecto Toachi-Pilatón, utilizando diferentes alternativas de deflectores los mismos que se ubican en el esquí del vertedero, de tal forma de ver cuál de estas alternativas logre que el impacto del chorro se produzca en la parte central del cuenco disipador de energía, evitando de esta manera que el efecto de socavación afecte la estabilidad de los taludes laterales del cuenco disipador. En este trabajo de titulación se expondrá las bases y criterios teóricos para el diseño de saltos en esquí y la configuración del chorro a la salida de los mismos, además se abordará el tema de la modelación física, misma que es fundamental para un estudio de esta índole, ya que se planteará teorías para la selección de escalas, semejanza y las restricciones del fenómeno a ser analizado. Como resultados obtenidos se concluye que la alternativa C (deflector peraltado), logra desviar de mejor manera el chorro hacia el centro del cuenco de disipación.The main goal of this research is to analize the jet´s form, reach and direction proyected by the right excess spillway of Toachi Dam. Different alternatives of buckets, which are located on the spillway Ski, are proved. Thus, it could be observed what bucket has produced a jet impact at the central part of the stilling pool. Furthermore, it would avoid that the undermining effect produces an instability of the lateral stilling pool slopes. This research will explain the theoretical basis and criteria about designing Ski Jumps and configuring the output jet. Moreover, Physical Model topic, which is essential in this study, will be addressed. Theories such as: scale selection, likeness and restriction will be proposed. In conclusion, the results show that alternative C (raised bucket) achieves a better jet deflect to the stilling pool center
Gremion Gérald - One of the best experts on this subject based on the ideXlab platform.
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Orientation of body segments in Ski Jumps using wearable sensors: Analysis of relevant parameters during stable flight phase
2011Co-Authors: Aminian Kamiar, Chardonnens Julien, Favre Julien, Cuendet Florian, Gremion GéraldAbstract:3D kinematic and dynamic analysis is highly required in Ski jumping. Current recording techniques (e.g. camera systems) suffered from limitations, such as volume capture or complexity of use and processing. This study proposed a new 3D approach based on inertial sensors to calculate automatically the whole body segments orientation of the entire jump during in-field measurements. Combination of accelerometers and gyroscopes allowed devising a functional calibration procedure adapted to Ski jumping activity. Then, segments orientation was obtained based on strapdown integration of gyroscopes. Finally, accelerometers were used to define in-run initial orientations and to improve segments orientations during stable flight. In order to show the efficacy of the proposed system, relevant 3D parameters of stable flight phase (V-and attack Ski angles, joint angles, drag and lift forces) were extracted from 86 Jumps of 34 jumpers. Combination of these parameters expressed 55% of whole variance of distance score
Julien Chardonnens - One of the best experts on this subject based on the ideXlab platform.
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Orientation of body segments in Ski Jumps using wearable sensors: Analysis of relevant parameters during stable flight phase
2010Co-Authors: Julien Chardonnens, Julien Favre, Florian Cuendet, Gérald Gremion, Kamiar AminianAbstract:Biomechanics analysis of the Ski jump is highly required. Some parameters and their interrelations have been reported in previous research studies limited to few athletes. The generalization of these parameters to athletes of various levels and under training conditions should be assessed, since they have the potential to be used for daily evaluation. This study proposed a new 3D approach based on inertial sensors to evaluate relevant kinematic and aerodynamic parameters of stable flight phase. The proposed wearable system can easily be used for daily training. Aerodynamic forces and body segments 3D angles were extracted during the stable flight phase of 86 Jumps. Then, their correlations with respect to distance as well as their interrelations were analyzed. Their combination expressed 55% of the total distance variance.