Дисертації: "Forehead"

1

Häller, Thomas Vincent. "Improved altertness through forehead cooling /." [S.l.] : [s.n.], 2009. http://www.ub.unibe.ch/content/bibliotheken_sammlungen/sondersammlungen/dissen_bestellformular/index_ger.html.

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2

Kleintjes, Wayne George. "The vascular anatomy of the forehead related to forehead flaps and its application in plastic and reconstructive surgery." Thesis, Stellenbosch : University of Stellenbosch, 2007. http://hdl.handle.net/10019.1/1144.

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3

Warburton, Mark. "Physically based forehead modelling and animation including wrinkles." Thesis, University of Sheffield, 2014. http://etheses.whiterose.ac.uk/7994/.

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There has been a vast amount of research on the production of realistic facial models and animations, which is one of the most challenging areas of computer graphics. Recently, there has been an increased interest in the use of physically based approaches for facial animation, whereby the effects of muscle contractions are propagated through facial soft-tissue models to automatically deform them in a more realistic and anatomically accurate manner. Presented in this thesis is a fully physically based approach for efficiently producing realistic-looking animations of facial movement, including animation of expressive wrinkles, focussing on the forehead. This is done by modelling more physics-based behaviour than current computer graphics approaches. The presented research has two major components. The first is a novel model creation process to automatically create animatable non-conforming hexahedral finite element (FE) simulation models of facial soft tissue from any surface mesh that contains hole-free volumes. The generated multi-layered voxel-based models are immediately ready for simulation, with skin layers and element material properties, muscle properties, and boundary conditions being automatically computed. The second major component is an advanced optimised GPU-based process to simulate and visualise these models over time using the total Lagrangian explicit dynamic (TLED) formulation of the FE method. An anatomical muscle contraction model computes active and transversely isotropic passive muscle stresses, while advanced boundary conditions enable the sliding effect between the superficial and deep soft-tissue layers to be simulated. Soft-tissue models and animations with varying complexity are presented, from a simple soft-tissue-block model with uniform layers of skin and muscle, to a complex forehead model. These demonstrate the flexibility of the animation approach to produce detailed animations of realistic gross- and fine-scale soft-tissue movement, including wrinkles, with different muscle structures and material parameters, for example, to animate different-aged skin. Owing to the detail and accuracy of the models and simulations, the animation approach could also be used for applications outside of computer graphics, such as surgical applications. Furthermore, the animation approach can be used to animate any multi-layered soft body (not just soft tissue).

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4

Dresher, Russell Paul. "Wearable Forehead Pulse Oximetry: Minimization of Motion and Pressure Artifacts." Link to electronic thesis, 2006. http://www.wpi.edu/Pubs/ETD/Available/etd-050306-104212/.

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Thesis (M.S.)--Worcester Polytechnic Institute.
Keywords: sensor attachment, wearable sensor, pulse oximetry, motion artifact, contact pressure, remote physiological monitoring. Includes bibliographical references (p.54-57).

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5

Worden, William Lamont. "Response of choroid and forehead blood flow to systemic phenylephrine infusion." [New Haven, Conn. : s.n.], 2007. http://ymtdl.med.yale.edu/theses/available/etd-08282007-153017/.

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6

Linhares, Daniele Sigal. "A relação da projeção do terço inferior da face com a região da glabela." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/23/23151/tde-03072017-154552/.

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O terço inferior da face exerce uma forte influência na estética dos indivíduos, e sabendo-se da importância do seu equilíbrio, e da contribuição do ortodontista quanto ao diagnóstico do perfil facial, o presente estudo teve por finalidades testar um método de correlação entre uma medida linear localizada a partir da região da glabela com medidas lineares anteroposteriores no terço inferior da face (Triviño, 2012), e verificar a previsibilidade de proporções anteroposteriores no terço inferior da face, a partir de uma linha de referência passando por um ponto na região da glabela. Desenhos anatômicos foram realizados através de telerradiografias em norma lateral de 120 indivíduos com harmonia facial, leucodermas e relação molar de classe I, com o intuito de estabelecer parâmetros cefalométricos para correlacionar referências anteroposteriores do terço inferior da face a partir das linhas Sv-PRT e PRTv, obtidas através do ponto PRT. A aplicabilidade do método foi realizada em um grupo de 24 indivíduos com perfil desagradável, em que considerou insatisfatória a aplicação das fórmulas de previsibilidade utilizando a linha Sv-PRT, como uma referência para determinar as proporções anteroposteriores do terço inferior da face em alguns pacientes. O método que considerou a linha PRTv como referência, através dos métodos estatísticos de correlação de Pearson e regressão linear múltipla, apresentou resultados estatisticamente significativos para todos os valores de referência nos indivíduos do gênero feminino e nos indivíduos do gênero masculino (PRTv-Ls, PRTv-Li e PRT-Pg\'). Foi utilizado o Teste t-Student para verificar que as medidas não foram estatisticamente significativas de acordo com o gênero. Os resultados deste estudo mostraram ser coerente considerar a região da glabela como uma referência de avaliação e diagnóstico para as proporções anteroposteriores do terço inferior da face.
The lower third of the face exerts a strong influence on the aesthetics of individuals, and knowing the importance of its balance, and the orthodontist\'s contribution to the diagnosis of the facial profile, the present study had the purpose to test a method of correlation between a linear measure located from the glabella region with linear anteroposterior measurements on the lower third of the face (Triviño, 2012), and verify the predictability of anteroposterior proportions in the lower third of the face, from a reference line through a point in the glabella region. Anatomical tracings from lateral cephalometric radiographs of 120 individuals with balanced profile, leucoderm and class I were performed in order to establish cephalometric parameters to correlate anteroposterior references of the lower third of the face from the lines Sv-PRT and PRTv, obtained through the PRT point. The applicability of the method was performed in a group of 24 individuals with an unpleasant profile, in which it considered the predictability formulas that used the Sv-PRT line as an unsatisfactory reference to determine the anteroposterior proportions of the lower third of the face in some patients. The method that considered the PRTv line as a reference, using Pearson\'s statistical methods of correlation and multiple linear regression, presented statistically significant results for all reference values in females and males (PRTv-Ls, PRTv -Li and PRT-Pg\'). The Student t-test was used to verify that the measures were not statistically significant according to gender. The results of this study showed that it is coherent to consider the glabella region as an evaluation and diagnostic reference for the anteroposterior proportions of the lower third of the face.

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7

Guerrero, Apolo Jesús David. "La impulsividad en adultos sanos: rasgos antropométricos y exploración estructural de la corteza cerebral." Doctoral thesis, Universitat Autònoma de Barcelona, 2018. http://hdl.handle.net/10803/664013.

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La historia de la Psicología refleja el interés por las formas y estructura del ser humano, siendo cráneo y rostro las más estudiadas para discernir aspectos de la personalidad. Por su relevancia en numerosos trastornos psiquiátricos una conducta que ha sido objeto de numerosas investigaciones es la impulsiva, de la que han surgido distintas conceptualizaciones con cierta controversia etiológica. En este sentido, nada se ha investigado sobre la relación entre este constructo y la estructura craneofacial. No obstante, el psiquiatra francés Louis Corman (1901-1995) en sus observaciones sobre la estructura craneofacial, afirmaba que una mayor inclinación de la frente hacia atrás se relacionaba con rasgos impulsivos, observación que no ha recibido atención hasta la fecha. Por otro lado, las técnicas de neuroimagen están ayudando a clarificar que tipo de variaciones se producen en las regiones cerebrales implicadas en la impulsividad. Y aunque la investigación se ha centrado mayoritariamente en población clínica, los estudios con población sana parecen estar recibiendo mayor atención en la última década. Así, está investigación se constituyó sobre tres objetivos y cuatro hipótesis. En el primer objetivo se investigó la asociación entre la impulsividad y el grado de inclinación de la frente hacia atrás (GIF), bajo la primera hipótesis que a mayor GIF mayor impulsividad. El segundo objetivo estudió la asociación entre la impulsividad y el volumen de la materia gris (VMG) de toda la corteza cerebral. Se formuló una segunda hipótesis que a menor VMG en regiones fronto-temporales mayor impulsividad. El tercer objetivo investigó la asociación entre GIF y VMG de toda la corteza cerebral y se planteó la tercera hipótesis que a mayor GIF menor VMG en regiones fronto-temporales. Asimismo, sobre la hipótesis anterior, surgió una cuarta hipótesis para observar si un hipotético mayor GIF y menor VMG en regiones fronto-temporales, se asociaría a mayor impulsividad. Los resultados confirman ampliamente la primera hipótesis, al obtener una alta asociación positiva entre 16 de 17 factores de impulsividad analizados y GIF. La segunda hipótesis confirma disminuciones en el VMG de regiones de los lóbulos fronto-temporales, aunque también se han hallado incrementos en estos lóbulos y en regiones del lóbulo occipital. En la tercera hipótesis, mayor GIF se asoció con tres regiones cerebrales. Se halló una disminución del VMG en el lóbulo frontal (giro caudal medio frontal derecho) y en el temporal (corteza transversal temporal derecha). También hallamos disminuciones de VMG en una región parietal (giro post-central derecho). Ello confirma nuestra hipótesis aunque se esperaba un mayor número de asociaciones negativas en regiones frontales. Finalmente, en la cuarta hipótesis y en el factor de impulsividad no planeada, se confirma una asociación positiva con GIF a la vez que disminuciones de VMG en la región de la corteza transversal derecha (lóbulo temporal). En conclusión, a mayor GIF mayor impulsividad autoinformada en sujetos sanos. También deducimos que numerosas regiones cerebrales parecen estar implicadas en este constructo. Asimismo, en regiones posteriores del encéfalo, como el lóbulo occipital, no se han hallado correlaciones entre GIF y VMG, lo que parece indicar que GIF puede relacionarse con el tejido cerebral subyacente de regiones anteriores del encéfalo. En esta línea, confirmamos que GIF se asocia a un menor VMG en regiones temporales que influyen en la impulsividad no planeada, y aunque este factor también se ha relacionado con áreas frontales, en esta región no se ha encontrado una asociación conjunta con GIF. Finalmente, aunque se trata de unos resultados iniciales, abren una incipiente línea de investigación sobre la relación conjunta entre la estructura craneofacial, el tejido cerebral subyacente y aspectos de la personalidad.
The history of Psychology reflects the interest in the forms and structure of the human being, being skull and face the most studied to discern aspects of personality. Due to its relevance in numerous psychiatric disorders, a behavior that has been the objective of numerous investigations is impulsiveness, from which different conceptualizations with a certain etiological controversy have emerged. In this sense, nothing has been investigated on the relationship between this construct and the craniofacial structure. However, the French psychiatrist Louis Corman (1901-1995), in his observations on the craniofacial structure, stated that a greater slant of the forehead backwards was related to impulsive features, an observation that has not received attention to date. On the other hand, neuroimaging techniques are helping to clarify what type of variations occur in the brain regions involved in impulsiveness. And while research has focused largely on the clinical population, studies of healthy populations appear to be receiving more attention in the last decade. Thus, this research was based on three objectives and four hypotheses. In the first objective, the association between impulsivity and the degree of backward slanted forehead (GIF) was investigated, under the first hypothesis that the greater the GIF the greater the impulsiveness. The second objective studied the association between impulsiveness and gray matter volume (GMV) of the entire cerebral cortex. A second hypothesis was formulated: the lower the GMV in front-temporal regions, the greater the impulsiveness. The third objective investigated the association between GIF and GMV of the entire cerebral cortex and the third hypothesis was that the higher the GIF the lower the GMV in front-temporal regions. Also, on the previous hypothesis, a fourth hypothesis emerged to observe whether a hypothetical higher GIF and lower GMV in front-temporal regions would be associated with higher impulsiveness. The results broadly confirm the first hypothesis, by obtaining a high positive association between 16 of the 17 impulsivity factors analyzed and GIF. The second hypothesis confirmed decreases in GMV in fronto-temporal lobe regions, although increases have also been found in these lobes and in occipital lobe regions. In the third hypothesis, increased GIF was associated with three brain regions. A decrease in GMV was found in the frontal lobe (right middle frontal caudal rotation) and in the temporal lobe (right temporal cortex). We also found decreases in GMV in a parietal region (right post-central rotation). This supports our hypothesis, although more negative associations were expected in frontal regions. Finally, in the fourth hypothesis and the non-planning impulsiveness factor, a positive association with GIF is confirmed as well as decreases in GMV in the region of the right lateral cortex (temporal lobe). In conclusion, the greater the GIF, the greater the self-reported impulsiveness in healthy subjects. We also infer that numerous brain regions appear to be involved in this construct. Also, in posterior regions of the brain, such as the occipital lobe, no correlations have been found between GIF and GMV, suggesting that GIF may be related to the underlying brain tissue of anterior regions of the brain. In this line, we confirm that GIF is associated with a lower GMV in temporal regions that influence non-planning impulsiveness, and although this factor has also been related to frontal areas, no common association with GIF has been found in this region. Finally, although these are initial results, they open an incipient line of research on the joint relationship between the craniofacial structure, the underlying brain tissue and personality aspects.

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8

Roman, Matej. "Automatizované měření teploty v boji proti COVID." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2021. http://www.nusl.cz/ntk/nusl-442439.

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This thesis focuses on the development of an open source software capable of automatic face detection in an image captured by a thermal camera, followed by a temperature measuring. This software is supposed to aid in the COVID-19 pandemics. The developed software is independent of used thermal camera. In this thesis, I am using TIM400 thermal camera. The implementation of the face detection was achieved by an OpenCV module. The methods tested were Template Matching, Eigen Faces, and Cascade Classifier. The last-mentioned had the best results, hence was used in the final version of the software. Cascade Classifier is looking for the eyes and their surrounding area in the image, allowing the software to subsequently measure the temperature on the surface of one's forehead. One can therefore be wearing a face mask or a respirator safely. The temperature measuring works in real time and the software is able to capture several people at once. It then keeps a record of the temperature of each measured individual as well as the time of the measurement. The software as a whole is a part of an installation file compatible with the Windows operating system. The functionality of this software was tested – the video recordings are included in this thesis.

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9

Funk, Merrill D. "Kinematic Changes of the Tennis Forehand Ground Stroke as Post Contact Ball Speed Increases." BYU ScholarsArchive, 2010. https://scholarsarchive.byu.edu/etd/2710.

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Neuromuscular and kinematic patterns during the tennis forehand have been studied extensively. However, no one has evaluated potential upper-extremity kinematic changes during the forehand as ball speed increases. The purpose of this study was to evaluate changes in shoulder and trunk kinematics as forehand ball speed increased, in an attempt to better understand how kinematics may promote forehand ball speed. Peak trunk rotation angle, shoulder horizontal abduction/adduction and internal/external rotation angle, and corresponding angular velocities were measured between initial backswing and ball contact during forehands that were performed at three different speeds (50%, 75%, and 100% of maximal post-impact ball speed). Between-speed differences were observed for all dependent variables. Internal humeral rotation velocity increased by 136% (from 477°/s to 1128°/s) while trunk rotation velocity increased by 91% (from 164°/s to 313°/s) and trunk rotation angle increased by only 26% (from 46° to 58°) as forehand ball speed increased from slow to fast. Two primary conclusions can be drawn from these results: (1) trunk and upper arm rotation (adduction and internal rotation) are important to produce forehand ball speed, and (2), increased joint angular velocity may be more important than altered joint position when attempting to produce maximal forehand ball speed.

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10

Ferreira, Thiago Rogel Santos. "Efeito da autofala na aprendizagem motora." Universidade de São Paulo, 2013. http://www.teses.usp.br/teses/disponiveis/39/39133/tde-06022014-114320/.

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O objetivo deste estudo foi investigar os efeitos da autofala na aprendizagem motora. A tarefa utilizada foi o forehand do tênis de campo. Oitenta e quatro universitários foram divididos em cinco grupos experimentais e um controle (n = 14). Dentre os grupos experimentais um deles utilizou-se de quatro dicas para direcionamento da atenção a elementos-chave da rebatida, os demais fizeram uso de apenas uma das quatro dicas (bola, quique, bater, pronto), já o grupo controle recebeu somente instruções gerais fornecidas a todos os participantes. Na fase de aquisição todos os grupos realizaram 180 rebatidas divididas em 60 por dia. Em seguida, eles realizaram um teste de transferência contendo 10 rebatidas com mudança da direção do outro alvo e, após 5 dias, um teste de retenção contendo 10 rebatidas nas mesmas condições da fase de aquisição. A variável dependente foi o acerto ao alvo localizado na quadra adversária. Os resultados mostraram que todos os grupos melhoraram os desempenhos na fase de aquisição, os quais foram mantidos nos testes de transferência e retenção. Entretanto, não foram encontradas diferenças entre os grupos. Concluiu-se que as aprendizagens do forehand com e sem a autofala apresentaram efeitos similares. E, ainda, que a autofala sobre quatro aspectos da tarefa foi similar àquelas com autofala de apenas um aspecto
The aim of this study was to investigate the effects of self-talk on the motor learning. The task was the forehand of the tennis. Eighty-four students were divided into five experimental groups and one control group (n = 14). One of the experimental groups used four cues for directing attention to key elements of forehand. The other groups have made use of only one of the four cues (ball, bounce, hit, ready), and the control group received only general instructions. In the acquisition phase all groups performed 180 trials which were divided into 60 per day. Then they performed a transfer test of 10 trials involving a shift in the target direction and, after 5 days a retention test was run with ten trials in the same conditions of the acquisition phase. The dependent variable was the hit to the target located in the opponent\'s court. The results showed that all groups improved their performances in the acquisition phase, which were kept in the retention and transfer tests. However, no differences were found between groups. It was concluded that the learning of the forehand with and without self-talk showed similar effects. And, that self-talk of four aspects of the task was similar to those with self-talk of only one aspect

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11

Neto, Ludgero Braga. "Características dinâmicas e eletromiográficas do forehand e backhand em tenistas: uma perspectiva biomecânica para avaliar o desempenho." Universidade de São Paulo, 2008. http://www.teses.usp.br/teses/disponiveis/39/39132/tde-11082008-113504/.

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O forehand e o backhand são as técnicas de movimentos mais utilizados no tênis. São golpes técnicos de complexa execução, pois dependem de uma perfeita sincronização temporal entre o movimento da raquete e a trajetória da bola. A literatura especializada demonstra que o posicionamento dos pés é fundamental para gerar potência nestes golpes e registra basicamente dois tipos de forehand quanto ao posicionamento dos pés: forehand open stance (FOS) e forehand square stance (FSS). A técnica de backhand, desde o início da prática da modalidade, apresenta duas maneiras de ser executada: com uma mão (BK1) ou com duas mãos (BK2) segurando o cabo da raquete. Pesquisas científicas específicas nesta modalidade esportiva têm se tornado razoavelmente freqüentes nas últimas duas décadas. O objetivo deste estudo é descrever as características biomecânicas a partir de parâmetros dinâmicos, cinemáticos e eletromiográficos segundo variáveis e músculos relacionados experimentalmente em função da utilização das quatro técnicas descritas acima. Através do conhecimento destas características biomecânicas, pretende-se ainda estabelecer uma relação de dependência quanto às influências no desempenho técnico esportivo. A amostra foi composta por dez indivíduos do sexo masculino, que possuíam domínio das técnicas analisadas. Ao analisarmos os resultados que reúnem as variáveis Biomecânicas estudadas, percebemos que é possível aceitar parcialmente a hipótese inicial de nosso estudo: as técnicas FOS e BK2 demandam maior ativação muscular quando comparadas com as técnicas FSS e BK1, respectivamente. Observando-se ainda os resultados de eletromiografia, verificamos a predominância de valores mais elevados de ativação muscular para as técnicas FOS e BK2 durante a fase pós-impacto, confirmando-se, portanto a hipótese inicial. Porém, durante a fase pré-impacto, os valores mais elevados de ativação muscular foram observados nas técnicas FSS e BK1, contrariando desta maneira a hipótese inicial. Concluímos, portanto, distintos comportamentos entre as duas técnicas de forehand e backhand, principalmente ao analisarmos as fases pré e pós-impacto, o que nos permitiu uma análise técnica detalhada dos gestos esportivos estudados, dada a complexidade estrutural dos mesmos
The forehand and the backhand are the most common movements in tennis. They are technical strokes of complex execution because they depend on perfect temporal synchronization between the racket\'s movement and the ball\'s trajectory. The tennis literature on the subject shows that the feet\'s positioning is crucial to generate power during these strokes. Two kinds of forehand are identified: the forehand open stance (FOS) and the forehand square stance (FSS). The backhand, since its origin, has appeared in two forms: the one-handed grip (BK1) and the two-handed grip (BK2). Scientific research on the subject has been conducted regularly during the two decades. Hence, the aim of this study is to describe the biomechanical characteristics within dynamic, kinematic and electromyographic parameters, and according to variables and experimentally related muscles in relation to the four different tennis techniques. In addition, through knowledge of these biomechanical characteristics, this thesis intends to identify the influences on technical sports performance. The sample was composed of males (n=10) that have mastery of the forehand and backhand strokes. After analyzing the results that evolve Biomechanics variables studied, we realized that it\'s possible to partially accept the initial hypothesis of our study: the forehand open stance and backhand strokes with both hands demand greater muscle activation when they are compared with forehand square stance and backhand stoke with just one hand, respectively. Still, observing the results of electromyography, we verified the predominance of the highest values of muscle activation for forehand open stance and backhand strokes with both hands during the post-impact phase, it\'s, thus, confirming the initial hypothesis. However, during the pre-impact phase, the highest values of muscle activation were observed in the forehand square stance and backhand strokes with one hand, counteracting, in this way, the initial hypothesis. We concluded, therefore, distinct behaviors between the two forehand and backhand strokes, mainly to analyze the pre and post-impact phase, which allowed us a detailed technical analysis of the sportive gestures studied, owing to its structural complexity

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12

Farrow, Damian Thomas, and mikewood@deakin edu au. "The effects of contextual interference on children learning forehand tennis groundstrokes." Deakin University, 1995. http://tux.lib.deakin.edu.au./adt-VDU/public/adt-VDU20060727.112040.

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Previous research on contextual interference theory in controlled laboratory situations consistently illustrated that random practice was superior to blocked practice when learning motor skills. However, when considered in relation to physical education class settings the findings of the contextual interference experiments were not as uniform. Furthermore, the results of the contextual interference research were ambiguous when an open skill was used as the experimental task, with no definite trend evident. Random practice was found more effective for learning (del Rey, 1989) whereas French, Rink and Werner (1990) demonstrated blocked practice to be superior. In the present study, the influence of high and low contextual interference as practice schedules was investigated within an applied sports setting using an open sports skill as the experimental task. Two groups of boys and girls, 8-9 and 10-12 years of age, were taught a forehand tennis groundstroke using both their preferred and non-preferred hands over a ten week coaching and practice period. The findings showed that male subjects were significantly better at the experimental task than female subjects at the pre-test stage only. The result also demonstrated that the 10-12 year old subjects were significantly better than the 8-9 year olds at the task with the exception of the preferred hand at the post and retention test stage. The contextual interference effect was demonstrated in the retention phase on the preferred hand of the 10-12 year old subjects where the random practice group was significantly better than the blocked practice group in an applied sports setting. These findings were discussed in relation to the role of cognition in the learning of these motor skills and the influence of the subjects related background experiences.

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13

Zhang, Peng. "The effects of play practice on teaching table tennis forehand skills." Columbus, Ohio : Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1211575204.

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14

Zhang, Zhiqing. "Biomechanical analysis and model development applied to table tennis forehand strokes." Thesis, Loughborough University, 2017. https://dspace.lboro.ac.uk/2134/24902.

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Table tennis playing involves complex spatial movement of the racket and human body. It takes much effort for the novice players to better mimic expert players. The evaluation of motion patterns during table tennis training, which is usually achieved by coaches, is important for novice trainees to improve faster. However, traditional coaching relies heavily on coaches qualitative observation and subjective evaluation. While past literature shows considerable potential in applying biomechanical analysis and classification for motion pattern assessment to improve novice table tennis players, little published work was found on table tennis biomechanics. To attempt to overcome the problems and fill the gaps, this research aims to quantify the movement of table tennis strokes, to identify the motion pattern differences between experts and novices, and to develop a model for automatic evaluation of the motion quality for an individual. Firstly, a novel method for comprehensive quantification and measurement of the kinematic motion of racket and human body is proposed. In addition, a novel method based on racket centre velocity profile is proposed to segment and normalize the motion data. Secondly, a controlled experiment was conducted to collect motion data of expert and novice players during forehand strokes. Statistical analysis was performed to determine the motion differences between the expert and the novice groups. The experts exhibited significantly different motion patterns with faster racket centre velocity and smaller racket plane angle, different standing posture and joint angular velocity, etc. Lastly, a support vector machine (SVM) classification technique was employed to build a model for motion pattern evaluation. The model development was based on experimental data with different feature selection methods and SVM kernels to achieve the best performance (F1 score) through cross-validated and Nelder-Mead method. Results showed that the SVM classification model exhibited good performance with an average model performance above 90% in distinguishing the stroke motion between expert and novice players. This research helps to better understand the biomechanical mechanisms of table tennis strokes, which will ultimately aid the improvement of novice players. The phase segmentation and normalization methods for table tennis strokes are novel, unambiguous and straightforward to apply. The quantitative comparison identified the comprehensive differences in motion between experts and novice players for racket and human body in continuous phase time, which is a novel contribution. The proposed classification model shows potential in the application of SVM to table tennis biomechanics and can be exploited for automatic coaching.

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15

Zhang, Peng. "The Effects of Play Pracice on Teaching Table Tennis Forehand Skills." The Ohio State University, 2008. http://rave.ohiolink.edu/etdc/view?acc_num=osu1211575204.

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16

Currie, Gary. "Optimizing racquethead-shuttle interaction for an effective overhead forehand clear in badminton." Thesis, McGill University, 1989. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=59550.

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The purpose of this investigation was to determine, the difference in selected kinematic variables of the shuttle-racquet head interaction for players of different ability levels executing the badminton overhead forehand clear. These variables included, (1) resultant velocity of the racquet head at contact, and (2) time between peak velocity and contact. This study also examined the total horizontal displacement of the shuttle after contact, the angle of deviation of the shuttle, the time of flight of the shuttle, the angle of projection of the shuttle after contact, and the shuttle velocity after contact. Six volunteer male subjects were divided equally into three groups corresponding to their ability; novice, intermediate, and advanced. Data were collected using a high speed motion picture camera. The data did not establish significant differences between the three groups with respect to the racquet head velocity at contact, or for the time differences between peak velocity and contact time. However, it was found that the angle of projection of the shuttle as well as the flight time of the shuttle decreased with ability.

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17

Law, Chi-hang. "Chunking occurs when rules are relevant to analogy learning in forehand topspin stroke of table tennis /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31941436.

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18

Law, Chi-hang, and 羅知行. "Chunking occurs when rules are relevant to analogy learning in forehand topspin stroke of table tennis." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45013913.

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19

Sogut, Mustafa. "The Effects Of Rhythm Training On Tennis Performance." Phd thesis, METU, 2009. http://etd.lib.metu.edu.tr/upload/12610859/index.pdf.

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The purpose of the study were
to compare the effects of tennis specific and general rhythm training on the forehand consistency performance, rhythmic competence, tennis playing level and agility performance, and to examine the effects of different tempos on rhythmic competence of tennis players. 30 university students whose mean score of International Tennis Number (ITN) was 7.3 (SD=0.9) were divided randomly into three sub-groups: tennis group (TG), general rhythm training group (GRTG), and tennis-specific rhythm training group (TRTG). Measurement instruments were ITN, Agility Test, Rhythmic Competence Analysis Test (RCAT), and Untimed Consecutive Rally Test (UCRT). A Kruskal-Wallis Test was conducted to calculate possible differences between initial scores and to compare improvement scores of groups. A Mann-Whitney U Test was conducted to determine pairwise comparisons of groups for improvement scores and to analyze RCAT scores for different tempos. Results revealed that participants in both rhythm training groups (GRTG and TRTG) improved their forehand consistency performance and rhythmic competence significantly after training period. Results for the improvement scores indicated that there was significant difference in UCRT (3m) between TRTG and TG and in RCAT (50) between both rhythm training groups and TG. On the other hand, participation to additional rhythm trainings was unable to differentiate tennis playing level and agility performance of groups. There was no significant difference between rhythm training groups for all parameters tested. Results also revealed that synchronization of participants&rsquo
movements with the external stimulus was more precise at fast tempo than at slow tempo.

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20

Genevois, Cyril. "Effets de l'entrainement sur la performance en coup droit et l'hypersollicitation du membre supérieur en tennis." Thesis, Lyon 1, 2013. http://www.theses.fr/2013LYO10327/document.

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L'objectif de ce travail de doctorat étati d'examiner les modalités d'entrainement permettant de développer la vitesse de balle post impact en coup droit au tennis, tout en évaluant les risques potantiels d'hypersollicitation de l'épaule qui pourraient en résulter. Les résultats de nos différentes études ont montré que la puissance maximale développée lors d'un lancer de medecine-ball (MB) à 2 mains sur le côté expliquait 25% de la variation de la vitesse maximale de balle en coup droit et qu'elle était atteinte en utilisant une masse de MB de 5,7% du poids de corps du joueur. Toutefois, les relations entre les distances obtenues lors de ce type de lancer et la vitesse de balle en coup droit sont faibles. En revanche, les lancers de MB sur le côté à une main ont démontré une relation significative avec la vitesse maximale de balle en coup droit. Un entrainement de six semaines basé sur l'utilisation de ce type de lancers a augmenté la vitesse de balle de 11% mais la précision des coups tendait à diminuer. Finalement, un entraînement incorporant des frappes de balle avec une raquette lestée d'environ 12% a également amélioré la vitesse maximale de balle en coup droit (5%), tout en conservant la précision des coups. Enfi, la comparaison de la coordiantion musculaire entre lesles deux types de lancers de MB et la frappe en coup droit a montré que les muscles du tronc et du membre supérieur testés présentaient des modèles d'activité musculaire et des niveaux de sollicitations similaires. Ainsi, les craintes concernant un potentiel de blessure ne sembleraient pas justifiées. Ainsi, les résulats de ces tudes ont contribué à la périodisation de la préparation physique pour l'amélioration de la performance en coup droit chez le joueur de tennis compétiteur amateur
This work aimed at exploring the training modalities to develop maximal post impact ball velocity fo the tennis forehand drive, while assessing the potential risk of upper limb oeruse. The results of our studies showed that maximal power developed during a two-handed side medecine-ball(MB) throw explained 25% of the variation of maximal forehand ball velocitiy, and was achieved when using a MB mass of 5,7 % of player's body weight. However, the relationship between throwing distances and maximal ball velocity of forehand drive was weak. By contrast, a significant relationship was found between the performance for the one-handed side MB throw and the maximal velocity of the forehand drive. A six-week trainig program based on one-hand MB throws increased the ball velocity by 11%, but the shot accuracy tended to be reduced. In the same way, a six-week training program including forehand drives with an overweighted racketr about 12 % allowed the maximal forehand ball velocity to be improved (5%), without alteration in theshot accuracy. Finally, the comparison of muscular coordination between both MB throws and the forehand drive demonstrated that the trunk and upper limb muscles presented similar activity pattern and levels. The potentials for injury risk would thus not justify. In conclusion, the finding of this work contributed to the periodization of the strength and conditioning training in order to improve the forehand drive performance in nonprofessional competitive tennis players

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21

Pereira, Francisco Jorge Almeida Henriques. "Forehead Detection in Thermal Camera using Deep Learning." Master's thesis, 2021. https://hdl.handle.net/10216/135348.

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22

Pereira, Francisco Jorge Almeida Henriques. "Forehead Detection in Thermal Camera using Deep Learning." Dissertação, 2021. https://hdl.handle.net/10216/135348.

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23

Carneiro, Manuel Francisco Reis. "Comfortable Fabric-Based Headband for Forehead EEG Monitoring." Master's thesis, 2019. http://hdl.handle.net/10316/88016.

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Dissertação de Mestrado Integrado em Engenharia Electrotécnica e de Computadores apresentada à Faculdade de Ciências e Tecnologia
Embora a aquisição de sinais biológicos (electromiografia, electrocardiografia, electrooculografia e electroencefalografia) seja uma tecnologia já estabelecida e bem estudada na prática clínica e em ambientes de investigação científica, os eléctrodos actualmente utilizados para interfacear com o corpo humano falham devido á falta de conforto após longos periodos de monitorização. Isto acontece principalmente porque os eletrodos são feitos de peças de hardware rígidas, incapazes de se adaptar bem à pele humana, delicada e frágil.Enquanto que no caso de ECG já existem soluções vestíveis móveis para monitoramento a longo prazo, como o Holter, este não é o caso do EEG, principalmente devido ao elevado número de eletrodos e fios necessários. As soluções atuais para o monitoramento a longo prazo dos pacientes são muitas vezes volumosas e desconfortáveis, além de serem caras e necessitarem de um alto nível de especialização e conhecimento para colocar os eletrodos no paciente. Além disso, os aparelhos de gravação EEG são muito propensos a interferências de ruído.A solução viável consiste em criar um dispositivo wearable com matrizes de eletrodos integrados e um amplificador integrado para reduzir os níveis de ruído nas leituras.Para colocar esta solução em prática, vários eletrodos flexíveis e elásticos serão integrados numa ”e-skin” de tecido, que também integra o circuito de amplificação necessário.Esta dissertação visa criar um dispositivo de aquisição de EEG para uso diário, de baixo custo e tamanho reduzido. Diferentes materiais (entre tintas e hidrogéis condutores à base de prata e carbono) para a fabricação de eletrodos são testados e comparados com eletrodos comercialmente disponíveis em termos da sua adequação para aquisição de biosinais.O hardware de amplificação e comunicação também é objeto de estudo e desenvolvimento e diferentes abordagens de conexão entre a amplificação e os eletrodos são testadas e comparadas em termos de níveis de ruído nas leituras de EEG, num esforço para reduzir os níveis de ruído no sistema de aquisição.O protótipo final é então comparado com o hardware comercialmente disponível para aquisição de EEG e são retiradas algumas conclusões.Em suma, o principal objetivo desta dissertação está relacionado com a implementação de um novo sistema de aquisição de EEG baseado numa ”e-skin” com materiais e métodos de estado de arte para fabricação de electrónica flexível e e-texteis. Uma aplicação simples do sistema implementado será por fim demonstrada, apenas como caso de estudo.
Although the acquisition of biological signals (electromyography, electrocardiography, electrooculography and electroencephalography) is an established technology and is already well studied in clinical practice and scientific research environments, the currently used electrodes for interfacing with the human body fail in terms of comfort for long-term monitoring. This happens mainly be- cause these electrodes are made of rigid hardware pieces, unable to conform well to the delicate and fragile human skin.While in the case of ECG, there are already mobile wearable solutions for long term monitoring, such as Holter, this is not the case for EEG, mainly due to the high number of electrodes and wires needed. Current solutions for long-term monitoring of patients are often bulky and uncomfortable, in addition to being expensive and needing an high level of expertise and knowledge to place the electrodes in the subject. Furthermore, these EEG recording sets are often prone to a lot of noise interference.The feasible solution consists of creating a wearable device with integrated electrode arrays and an integrated amplifier for reducing noise levels in the readings.To put this solution into practice, multiple stretchable and flexible electrodes will be integrated in a fabric-based e-skin patch, which also integrates the needed amplification circuitryThis dissertation aims at creating an everyday wearable, low cost, low size, EEG acquisition de- vice. Different materials (among silver and carbon based conductive inks and hydrogels) for the electrodes’ fabrication are tested and compared with commercially available electrodes in terms of their suitability for acquiring bio-signals.The amplification and communication hardware is also subject of study and development and different connection approaches between the amplification and the electrodes are tested and compared in terms of noise levels in the EEG readings, in an effort to reduced noise levels in the acquisition systemThe overall prototype is then compared with commercially available hardware for EEG acquisition and conclusions are withdrawn.In summary, the main objective of this dissertation is related with the implementation of a novel e-skin based EEG acquisition system with SOTA materials and methods for stretchable electronics and e-textile fabrication. Simple application of the implemented system will be demonstrated, only as a case study.
Outro - This work was partially supported by the national funds of the Foundation of Science and Technology of Portugal through the CMU-Portugal project Stretchtronics (Nr. CMUP-ERI/TIC/0021/2014), and Dermotronic (02/SAICT/2017 - 31784), co-financed by the European Regional Development Fund (FEDER) through “Programa Operacional Regional do Centro” (CENTRO2020)

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24

Weng-ChonChoi and 蔡永俊. "Feasibility Analysis of Forehead EEG-based NeurofeedbackTraining System." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/asw5k4.

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25

Tsai, Hsing-Yu, and 蔡幸育. "Automatic Sleep Stage Classification System Using Forehead EEG Signals." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/37101791152630784476.

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碩士
國立交通大學
生醫工程研究所
99
Polysomnography (PSG) is a common used method to diagnose sleep problems. However, a standard sleep study is a time consuming manual process. One shall wait for few weeks before proceeding a sleep study and wait another week for the report. Besides the waiting, the wires attached to a subject, the conductive gel applied to the electrodes and the unfamiliar environment would all disturb one’s sleep. In this thesis, a light weight sleep stage scoring system using forehead channels is introduced. Multiple classifiers were combined into a hierarchical classification system to perform automatic sleep stage classification using only Fp1 and Fp2 EEG signals. This system can separate REM sleep without EOG signals and achieve about 70% of agreement with expert’s scoring result. This system could provide a preliminary result and help deciding if a standard sleep study is required. This system also provides the possibility of long term sleep monitoring at home.

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26

Tang-WeiLin and 林唐暐. "Development of a Photoplethysmography-based Forehead-type Physiological Signal Monitoring System." Thesis, 2018. http://ndltd.ncl.edu.tw/handle/drtfev.

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碩士
國立成功大學
資訊工程學系
106
According to the statistics, about 6% population suffers from sleep apnea in the U.S. Sleep apnea may lead to mental discomfort, headache and doze. These symptoms cause discomfort in daily life. Moreover, they may lead to accidents (e.g., car accidents). Therefore, sleep apnea should not be ignored. At present, polysomnography is commonly used to perform overnight sleep recordings so as to determine whether or not the patient has sleep apnea. However, due to the limited resources in hospitals and sleep centers, patients have to wait for weeks or even months for polysomnography. Besides, sleeping in an unfamiliar place such as a hospital or a sleep center may cause poor sleep quality, affecting the accuracy of sleep diagnosis. Generally, polysomnography is not suitable for home use. One reason is that, it is too expensive, and the other reason is that, it requires a long time to setup a larger number of sensors for polysomnography. The proposed system is designed as a wearable device based on photoplethysmography (PPG). The system has low cost, and it does not require setting up a lot of sensors for physiological signal recording. The system can report the degree of blood oxygen saturation, heart rate and respiratory rate. The proposed system has been compared with the polysomnography measurement on oxygen saturation, heart rate and respiratory rate. Besides, by the change of heart rate, the proposed system can detect sleep apnea events. The accuracy of the sleep apnea detection method reaches 84%. Thus, the proposed system can be used for sleep apnea self-screening, allowing the user to evaluate whether or not to go to seek medical attention.

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27

SU, WEN-HUI, and 蘇紋慧. "Research on the use of Forehead Brainwave Signal of Distinguish Different Temperature." Thesis, 2016. http://ndltd.ncl.edu.tw/handle/65051895874913533874.

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Анотація:

碩士
國立高雄大學
電機工程學系碩士班
104
This paper is to analyze the forehead EEG signal variation when the subject’s hand is put in hot or cold water. Compared to many previous researches need to apply conductive plastic before wearing EEG caps, we adapt dry conductive plastic when using Neurosky's mindband. 20 participants closed their eyes for hot or cold temperature in this research. The EEG raw data is received by Bluetooth using the wafer of NeuroSky. The frequency component of the signals is obtained using FFT transform. The frequency characteristic of the signal for hot or cold temperature has been analyzed and discussed. It is possible to distinguish between hot or cold water using forehead EEG signal by comparing the difference in the frequency and the statistics.

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28

Fu-yi, Chien, and 簡富儀. "The effect of Qi-kung training on forehead and forearm muscle oxygen distribution." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/22972792457046339286.

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碩士
臺北巿立體育學院
運動科學研究所
98
With the development of human science, there are a number of studies of Qi-kung mechanism to physiology confirmed. Qi-kung can increase the blood flow of skin micro-circulation; through short-term Qi-kung training blood lactate decreases effectively after the exercises. Qi-kung can improve physiological function but aerobic capacity to tissues has not understood yet, so this study likes to realize the effect of Qi-kung training to aerobic capacity in tissues. This study was designed to observe the variation of oxygen concentration in tissues before and after Qi-kung training. Ten middle-aged volunteers without chronic diseases involve in participating in this study and take measurement of oxygen concentration of the forehead and left forearm with Near-infrared spectroscopy system (NIRS, ISS, USA). The results showed that there were remarkable increases in oxygen hemoglobin concentration to forehead and forearm and oxygen hemoglobin saturation percentage to left forearm, but obvious decrease in dexoy-oxygen hemoglobin concentration to forehead； total hemoglobin concentration in the forehead and left forearm there was no significant difference. This study demonstrate that Qi-kung could remarkably increase blood flow, and circulation and deliver sufficiently oxygen and nutrients, then it also help to remove metabolic wastes. Therefore, taking Qi-kung every day can deliver ample blood to every part in body and naturally increase cell activities, enhance immunity and achieve wellness .

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29

Chen, Po Chuan, and 陳柏銓. "Using Forehead-Channel Activities to Detect Driver's Drowsiness in a VR Based Driving Environment." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/78095657086703671457.

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Анотація:

碩士
國立交通大學
多媒體工程研究所
96
Previous studies showed that the alpha power increases in the occipital lobe highly related to human drowsiness. However, the acquisition of occipital EEG signals with the traditional electrode cap is inconvenient. Thus, the main purpose of this study was to confirm whether the forehead EEG signals could reflect the driver’s drowsiness and be able to use to estimate driver’s driving trajectory for constructing a feasible detecting system that can be applied in real life. Brain signals acquired from the occipital and the frontal lobe were analyzed and compared in this study. The frequency power changes in these components were used as features and fed into linear regression model to predict driver’s driving performance. Results showed the highest estimation accuracy was yielded with the features extracted from the occipital ICs cluster. We also found that there is another drowsiness-related brain source located in the frontal lobe. Furthermore, the increases of the theta power in the frontal lobe also highly correlated to the driver’s drowsiness. Comparing the conventional methods using the occipital activities, the estimation accuracy using the forehead signals is slightly lower but the estimation accuracy was still higher than 0.8. Results demonstrated that forehead signals could be used to estimate the drivers’ drowsiness. The new detecting system, using forehead signals, not only can correctly estimate the user’s drowsiness but also can drastically reduce the preparation time. In the future, such detection system will be easily and widely applied in the real operational environments.

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30

Lai, Wei-Kai, and 賴威凱. "Wireless Forehead EEG and Eye-blink Feature Extraction for Enhancing Alertness in Fatigue Driving." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/9t5a9h.

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Анотація:

碩士
國立交通大學
生物科技學系
104
Driver fatigue problem is one of the important factors that cause traffic accidents. Recent years, many research had investigated that using EEG signals can effectively detect driver’s drowsiness level. However, real-time monitoring system is required to apply these fatigue level detection techniques in the practical application, especially in the real-road driving. In this study, we investigate to obtain a better and precise understanding of brain activities of mental fatigue under driving, which is of great benefit for devolvement of detection of driving fatigue system. The experiments based on a sustained-attention driving task, which was implemented in a virtual-reality (VR) driving simulator. We were performed for 15 subjects to study Electroencephalography (EEG) brain dynamics by using a mobile and wireless device (referred to herein as Mindo-4), which consists of foam-based electrodes, data acquisition module, Bluetooth transition module, and rechargeable battery. In addition, we also synchronous record Electrooculography (EOG) by using neuroscan system. In our preliminary results, we found the power spectral analysis showed that the dry EEG system could distinguish an alert EEG from a fatigue EEG by evaluating the spectral dynamics of delta and alpha activities. Furthermore, eye-blink analysis also showed that when people feel fatigue, the blink frequency will decrease, and the blink amplitude will increase. Based on the outstanding training results, the RMSE of system would decrease to 0.034±0.019 and the squared R would increase to 0.885±0.057 in the with-in subject leave-one-trial-out cross validation test. In statistics, the performances of system increased significantly after the features of eye-blink were added. As the system performance of with-in subject leave-one-subject-out cross validation test, the system accuracy would obtain 70% when multiple linear regression (MLR) model used combination features of the EEG power spectra of 1-30 Hz and eye-blink parameters. These results indicate that the combination of a smartphone and wireless EEG device constitutes an effective and easy wearable solution for detecting and preventing driver fatigue in real driving environments.

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31

Wei, Chih-Liang, and 魏誌良. "Developing algorithms to distinguish insomnia patients from normal people via the single channel forehead signal." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/48789527989923262851.

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Анотація:

碩士
國立中山大學
機械與機電工程學系研究所
104
Polysomnography (PSG) is considered the gold standard in the diagnosis of sleep disordered breathing. However, compared with the single channel EEG sensor, PSG is difficult to operate, expensive and not suitable for home use. However, with fewer number of signals, the single channel senor provides much less information than PSG. Hence, extracting sufficient information from a single channel signal is a very important task. Considering the fact that insomnia is the most prevalent sleep disorder, this thesis is aimed to develop algorithms to distinguish insomnia patients form normal people via single channel forehead signal. In specific, we use three different approaches to analyze the forehead signal during sleep in order to identify features that have significantly different values between insomnia patients and normal people. The first method uses the zero crossing point interval to characterize the speed of the signal. The second method uses the continuous wavelet transform (CWT) to generate a series of features to assess the time-frequency domain properties of the signal. The third method uses the multiscale entropy criterion to quantify the complexity of the signal. In addition to comparing the value of the features, we also used the percentile rank of these features. By using the Wilcoxon''s rank-sum test to find out which of these features have significantly different median values in the two groups, 23 features were selected to classify insomnia patients from normal people by using Quadratic Discriminant Analysis (QDA). Selected from these 23 features, we tested many pairs of features. The best classification result was obtained by the combination of the zero crossing point interval and a CWT feature. The best classification accuracy is 97.8%. Additionally, we have identified 50 different feature pairs that can achieve classification accuracy of 90% or higher. According to these promising classification results, our algorithm has the potential to effectively distinguish insomnia patients from normal people. With the simplicity of single channel measurement requirement, the proposed approach is ideal for home use. As a result, the proposed method has the potential to become a home-based insomnia screening tool.

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32

David, Matei. "Multiparty Communication Complexity." Thesis, 2010. http://hdl.handle.net/1807/24736.

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Communication complexity is an area of complexity theory that studies an abstract model of computation called a communication protocol. In a $k$-player communication protocol, an input to a known function is partitioned into $k$ pieces of $n$ bits each, and each piece is assigned to one of the players in the protocol. The goal of the players is to evaluate the function on the distributed input by using as little communication as possible. In a Number-On-Forehead (NOF) protocol, the input piece assigned to each player is metaphorically placed on that player's forehead, so that each player sees everyone else's input but its own. In a Number-In-Hand (NIH) protocol, the piece assigned to each player is seen only by that player. Overall, the study of communication protocols has been used to obtain lower bounds and impossibility results for a wide variety of other models of computation. Two of the main contributions presented in this thesis are negative results on the NOF model of communication, identifying limitations of NOF protocols. Together, these results consitute stepping stones towards a better fundamental understanding of this model. As the first contribution, we show that randomized NOF protocols are exponentially more powerful than deterministic NOF protocols, as long as $k \le n^c$ for some constant $c$. As the second contribution, we show that nondeterministic NOF protocols are exponentially more powerful than randomized NOF protocols, as long as $k \le \delta \cdot \log n$ for some constant $\delta < 1$. For the third major contribution, we turn to the NIH model and we present a positive result. Informally, we show that a NIH communication protocol for a function $f$ can simulate a Stack Machine (a Turing Machine augmented with a stack) for a related function $F$, consisting of several instances of $f$ bundled together. Using this simulation and known communication complexity lower bounds, we obtain the first known (space vs. number of passes) trade-off lower bounds for Stack Machines.

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33

Tai, Yu-Lin, and 戴幼琳. "Trunk EMG during tennis forehand stroke." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/66289612655402860415.

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Анотація:

碩士
國立臺灣師範大學
運動科學研究所
101
Purpose: To investigate the change of electromyography (EMG) on trunk muscles during a tennis forehand stroke in different stances and directions. Methods: Twelve advanced males tennis players (right handed) performed two stances (open & square stance) and directions (crosscourt & down the line) forehand stroke. The left and right external oblique (LEO & REO), latissimus dorsi (LLD & RLD), and erector spinae (LES & RES) EMGs were collected and compared. The image time of every motion recorded by CASIO digital camera was divided into the preparation, acceleration and follow through phases. A 3-way ANOVAs of repeated measures (α = .05) and LSD for posteriori comparison were used for analysis. Results: The LEO muscle activation was affected by directions. The EMG of crosscourt hits was greater than down the line hits. The interaction of directions and phases impacted on REO, while LES was influenced by the interaction of stances and phases, but they both were no significant in three phases. Also, six muscles were affected by phases. The activation in the acceleration phase were the hightest, except for the LES, the transforming percentage of peak was greater in the preparation phase to the follow through phase, others five muscles changed from the follow through to the preparation phase. Conclusion: It’s important to train LEO muscle to intensify forehand drive crosscourt. During a tennis forehand stroke, LES muscle will activate first. It is the key point to start the force for the trunk with forward racket swing.

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34

Chien, Chien-Hua, and 簡健華. "Biomechanical Analysis of Table Tennis Forehand Drives." Thesis, 2010. http://ndltd.ncl.edu.tw/handle/29169049798548514216.

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Анотація:

碩士
國立臺灣師範大學
體育學系在職進修碩士班
98
The purpose of this study was to investigate the kinematical variations between the movements of forehand drive in straight and diagonal line when receiving topspin and backspin services of elite table tennis male players. Five collegiate elite table tennis male players in Taiwan were served as the participants. Ten Vicon Motion Capture systems MX13+ (250 Hz) were used to collect the movements of forehand drives, and the Vicon Nexus 1.4 soft ware was used to calculate the kinematic parameters. All the variables were tested by Friedman two-way analysis of variance nonparametric statistical test which was calculated by SPSS 17.0, and the post-hoc comparison were calculated by the Excel software, the significant levels as α = .05. The results as follows: The duration time of each phase of the forehand drives were different. The duration time of backswing were significant less while receiving the backspin than receiving the topspin. The duration time of swing forward movement in diagonal line was less than in straight line. In the swing velocity at contact point and the peak velocity of swing, the drive of receiving backspin was faster than receiving topspin. The center of gravity (COG) of receiving backspin drive in straight line was the lowest among the four movements while in the end of backswing, the contact point and the fastest swing point. The relative sagittal distance between the racket and the COG at contact of forehand drive in diagonal line were more than the distance of the straight line. The racket tilt angle was less when receiving the topspin than the backspin. The shoulder axis (upper trunk) rotation of receiving backspin in diagonal line was the greatest among the four different drives, and it was the least while receiving topspin in straight line drive. There were significant differences in the upper and the lower limb joints angle and angular velocities among the four different drives.

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35

Hsueh, Yi-Chang, and 薛尹彰. "Biomechanical analysis of badminton forehand net shots." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/grngrm.

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Анотація:

碩士
國立臺灣師範大學
體育學系
97
Net shot is the finest skill in the badminton game. The dab shot, the stab shot and the cross court net shot are the main techniques of this skill. The purpose of this study was to compare the kinematics and electromyography variables of forehand dab shot, stab shot and cross court shot of badminton. The subjects were eight elite collegiate male badminton players (ages: 21 ± 2 years; height: 176 ± 8cm; weight: 68 ± 6 kg). The mark trajectories were collected by VICON system (250Hz) and the kinematic variables were computed by Visual 3D software. The electromyography variables were recorded by the Biovision system (1000Hz) and analyzed by the DasyLab 6.0 software. All the variables were tested by Friedman two-way analysis of variance nonparametric statistical test which was calculated by SPSS 13.0, and the post-hoc comparison were calculated by the Excel software, the significant levels as α= .05. The results were: There was a less angle between the racket surface and the horizontal plane in the dab net shot, the players would slower the upper limbs stretch movement and co-contract the upper limb muscle groups before the contact point. The players performed the stab net shot with a faster COG displacement, stretched distal segments and a sequence burst in muscle groups of dominate limbs in order to make a faster racket velocity to stab the shuttle. The players performed cross court net shot with an obvious trunk rotation, upper arm interotation, forearm pronation and greater angle in racket surface with horizontal plane to hit the shuttle. We should slow down the movements in the dab shot to reduce the reaction force between the racket and the shuttle. The players should performed a faster stretch of distal segments and COG in stab net in order to create a greater eccentric force to hit the shuttle. The players increased the upper arm interotation and the forearm pronation to hit the shuttle by inward racket swing.

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36

Shieh, Jia-Bin, and 謝嘉彬. "The qualitative analysis of badminton forehand overhead clear." Thesis, 2004. http://ndltd.ncl.edu.tw/handle/87619867822837888626.

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Анотація:

碩士
國立體育學院
運動科學研究所
92
Badminton is one of the racket sports. There are many techniques to learn. The most important and basic skill is forehand overhead clear. The purpose of this research is focus on qualitative analysis of forehand overhead clear. We reviewed some articles and interview professional players, coaches, and then analyze and compare all these data. We also take serial pictures during the actions of forehand overhead clear by using digital camera. We got two results: 1. the model sketch of badminton forehand overhead clear by stroke athletic qualitative analysis. 2. Esteblishing the criteria sheet for forehand overhead clear. All these will help the beginner learning how to play it. Coach of badminton can diagnose if the player doing right by using them. Further more to correct the wrong position and prevent the damage from doing wrong. According to this research, we make some suggestions for teachers and coaches of badminton.

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37

WANG, Lu-Miin, and 王露敏. "Biomechanical Analysis of Badminton Forehand and Backhand Services." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/10061376356274593611.

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Анотація:

碩士
國立臺灣師範大學
體育學系
98
The purpose of this study was comparing the EMG and kinematical variables between badminton forehand and backhand services. Eight collegiate level one male badminton players (age: 19.63 ±1.5 yr, height: 175.25 ±6.32 cm, weight: 66.75 ±4.77 kg, experience: 9.38 ±1.19 yr.) in Taiwan served as the participants. The EMG variables were recorded by the Biovision system (1000hz) to collected the surface EMG signal of eleven muscles on the dominate right-hand, including flexor carpi ulnaris, pronator teres, flexor carpi radialis, extensor carpi radialis, brachioradialis muscle, biceps brachii, triceps brachii, pectoralis major, anterior deltoideus, posterior deltoideus, trapezius. The EMG and IEMG signals were analyzed by AcqKnowledge 3.9.1 software. The kinematical variables were recorded by Vicon MX-13 system (250Hz) and computed by Vicon nexus1.2 software. The Wilcoxon matched-pairs signed-rank nonparametric statistical test was to test between forehand and backhand serves for the differences in EMG data and motion variables. The Friedman two-way variance analysis of nonparametric statistical test was to test among three different path serves (low, flat and clear serves). The statistical analysis were calculated by the software of SPSS 17.0 and the post-hoc comparison were calculated by the Excel software, the significant levels as at α=.05. The results showed that there were the greater contact heights, the shorter distance, the less movement time and less expectable in the backhand serves than in the forehand serves. During serving, the backhand serves seemed having more advantages than the forehand serves. In rapid serves just like the flat and clear serves, there were greater EMG amplitude signals on the triceps brachii and posterior deltoideus. As on the results of this study, we recommend that the badminton players should used the backhand serves in the games to increase the possibility to win the game.

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38

Chia-Yu, Chen, and 陳佳郁. "The Effect of Constraints on Tennis Forehand Stroke." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/00304583234974131619.

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Анотація:

碩士
國立臺灣師範大學
體育學系
99
Tennis is one of the common physical education curriculums in colleges and the forehand stroke is the most important fundamentals. The beginners usually can easily meet the assessment requirement when hitting against the wall, but the performance level significantly dropped when transferring to the court. Purpose: The study investigated the performance outcome and the coordination pattern of the tennis beginners when executing the forehand strokes under different environment and task constraints. Methods: Eight male college students majoring in PE related areas were instructed to execute the forehand stroke under 2 environmental conditions (to the wall and on the court) and 2 distances (6m and 9m from the net/wall). Gyro 3D motion digitizing system (120Hz) was used to capture the movement kinematics of the 12 joints, yielding a total of 36 dimensions of the movement for principal component analysis (PCA). Two synchronized high-speed cameras (200Hz) captured the movements of the participants and the moments of ball contact. These data were analyzed with the Kwon 3D motion digitizing system. Performance outcome was recorded by another digital camera placed on the front of the target areas. Results: The performance outcomes at 6-m were significantly better than those at 9-m; and the performance outcomes in the wall environment were significantly higher than those on the court. The influence of the distance to the court environment was larger than that in the wall environment. The contact points in the short distance were in advance to the long situation. The speed of the ball before contact were higher for the long distance conditions than that for the short distance conditions, and the variability of the ball speed were higher on the court condition than that in the wall condition. The PCA results showed that the 4 or 5 principal components were sufficient to explain over 75% of variance for both environments. The swing movement of the forehand stroke on the court was interpreted by the 1st and 3rd components, and the left hand movement which was to maintain the balance of the swing movement was interpreted by the 2nd component. The 4th and 5th components were related to the lower limbs and right segments of the body movements. For the wall condition, the movements of the 1st, 2ed, 3rd and 4th components were similar to the 1st, 2ed, 4th and 5th components of the court condition, respectively. The results of effective value showed the range of the swing movement of the long distance shots were larger than the short distance shots. Conclusions: The different environments and distances showed different task difficulties, and the ball-racket contact points could also be the key factor for executing forehand stroke successfully. While the range of motion differentiated the long from the short distance strokes, the coordination patterns in both environmental conditions basically were the same.

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39

Wu, Chin-Tai, and 吳金黛. "Biomechanics of lower extremities during forehand volley in tennis." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/52201350310122436942.

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Анотація:

碩士
國立成功大學
體育健康育與休閒研究所
96
The purpose of this study is to investigate effect of foot insole on lower extremities biomechanics during the cutting movement of forehand volley in tennis. Six male tennis players without history of lower limb injury volunteered for this investigation. Subjects perform three cutting angles movements (0°, 30° & 60°) to hit a dropping ball with a racket. Subjects are asked to wear a tennis shoe (Adidas 012508, size US: 9.5) under two conditions: with its insole and an adhesive insole. Eight-cameras vedio system (Motion Analysis Corp., Santa, Rosa, CA, US) was used to collect the data (different condition in cutting angles and insole) of 3D kinematics. One force platform (Kitsler, Type 9281B, 1000Hz) was used to determine the ground reaction force (GRF). During the experiment, both the motion analysis system and the Kitsler’s force platform are activated at the same time. The result shows that there is no significant difference in the kinematics parameters of the ankle during early stance. Because the movement during early stance is belong to a task-oriented skill, which would lead to different modifications by the subjects. Highest medio-lateral and vertical forces occurred while performing 0° cutting angle with adhesive insole, that increases the stop ability during early stance. The eversion angle, and angular velocity, plantarflexion angle and angular velocity increase with an increase in cutting angle with normal insole during late stance. According to the results, the subjects perform higher cutting angle with normal insole seem to have higher chance to get Achilles tendon injury. The risk factors of adhesive insole with 60° cutting angle are smaller than normal insole. Therefore, the subjects perform 60° cutting angle with adhesive insole has more ankle stability than normal insole during the late stance. Most tennis injuries in lower extremity seem to be caused by push-off during the late stance, and the reduction of foot slipping inside the shoe would improve the ankle stability.

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40

Lao, Iong Tek, and 柳融迪. "Exploring the coordination patterns of badminton backcourt forehand swing." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/79562841957010260648.

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Анотація:

碩士
國立臺灣師範大學
運動科學研究所
100
Badminton in Asia has been a quite prevalent sport. In recent years, Taiwan's badminton players had great performance in the international competitions. In Badminton games, the consistent movement patterns of the swing are considered to be advantageous because of the reduction of the preparation time from the opponents before returning the shots . Literatures on the backcourt overhead strokes have indicated that there are no differences during the preparation phase of the strokes for the clear, drop, and smash shot, however, there are differences at the striking point of the 3 strokes. In this study, the coordination patterns of the forward swing from the 3 types of stroke were investigated based on the dynamical systems theory. Purpose: To investigate the differences of the coordination patterns of the clear, drop, and smash shot under the actual and deceiving conditions. Methods: Eight national level badminton players participated in the study. Two high-speed cameras and Kwon 3D 3.1 software were used to capture the kinematics of the joints of the wrist, elbow and shoulder. The two-way repeated measure ANOVA was used to analyze the angle-angle diagram and the relative phase of each pair of joints in three different shots and 2 different conditions. Results: The shoulder joints are more stable than the elbow and wrist joints in the spatial coordination pattern. The wrist and elbow joints are more stable in the temporal coordination pattern. Conclusions: The spatial coordination patterns of the shoulder-wrist joints from the swing phase to the striking phase are different when the deceiving shots are implemented. These differences can be used as the important pre cue for the receiving shots from the opponents.

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41

Liang, Hsi-Chien, and 梁世建. "Table Tennis Forehand Drive Movement Three-Dimensional Kinamatics Analysis." Thesis, 2006. http://ndltd.ncl.edu.tw/handle/25051005181668015853.

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Анотація:

碩士
國立臺北教育大學
體育學系碩士班
95
Table Tennis Forehand Drive Movement Three-Dimensional Kinamatics Analysis Advisor: Tsu-Lin Wong, Ph.D. Graduat Student: Hsi-Chien Liang Abstract This research aims to examine table tennis (ping pong) forehand drive movements during paddle raising (preparation) period, swing to hit (strike) period, continued swing period, and return to original posture period. Specifically this research examines the kinematics parameters related to: time, distance, displacement, and speed of paddle swing, as well as player joint angle changes and speeds of joint changes, and speed and displacement of player center of gravity changes. The test subjects include two female adult team members of the Guo Tai Table Tennis team, who are also Taiwan National Team members, and two junior male members of Taiwan National Team. All four players are right-handed and hold their paddles in the “handshake” style with the reversed rubber face of the paddle used in forehand drive. The average age, height, and weight of the players are 15.53 ± 1.01 years old, 160.25 ± 4.79 cm, and 58.75 ± 11.64 Kg, respectively. The equipment includes two Mega Speed (120 Hz) video cameras for synchronized taping. Before the experiments, the equipment recorded the 3D reference frame for 5 seconds, and 21 reflectors were placed on each player at important joint locations. A Smart-Pong szs-3000 robot was used to produce long, topspin serves, and forehand drives from the players were video taped. The images were processed with Kwon motion analysis system model trimmer, Direct Linear Transformation, and Wave Filter. Then, the data were processed with Excel and Origin statistic and graphing software to obtain kinematics parameters of human body in the 3D movements. These experiments produced the following results: (1) Forehand drive movement duration ratios: paddle raising period accounts for about 20% of the whole movement duration, swing to hit period accounts for about 10%, continued swing after the hit accounts for about 17%, and return to the original posture accounts for about 39%. The entire durations in the current studies are similar to those previously reported. However, the present studies show relatively shorter duration for paddle raising and longer duration for return to the original posture; these are different from the previously reported findings. (2) Forehand drive displacement ratios: paddle raising accounts for about 24% of the entire displacement (distance), swinging the paddle to hit the ball accounts for about 23%, continued swing after the hit accounts for about 28%. The entire distances are similar to previously reported results. However, current studies revealed shorter distances for the paddle raising and longer distance for the return to the original posture. These two aspects are also different from the previous studies. (3) Results from the current studies revealed that the average paddle swing speed is 11.00 ± 1.30 meter/second, and the maximum speed average is 15.71 ± 0.01 meter/second. These results are very similar to previous results. (4) Changes in the angles of the shoulder joints and the elbow joints during a forehand drive: paddle raising period: 3.06 ± 8.60 degrees for the shoulder joint, and 37.44 ± 12.47 degrees for the elbow joint; swing to hit the ball: 21.55 ± 7.47 degrees for the shoulder joint, and -18.68 ± 8.34 degrees for the elbow joint; continued swing after the hit: 37.87 ± 9.81 degrees for the shoulder joint, and -29.76 ± 12.57 degrees for the elbow joint; return to the original posture: -59.99 ± 8.79 degrees for the shoulder joint, and 2.91 ± 13.42 degrees for the elbow joint. These results, like previously reported results, show substantial variations among the players. (5) The upper limb joint movement speeds progressively increase from the proximal end to the distal end, i.e., paddle speed > wrist speed > elbow speed > shoulder speed. This observation is consistent with human body movement chain principles. Both adult National Team members have various joint movement speeds faster than those of the two junior National Team members. These results are similar to the previously reposted results. Although these results do not completely conform to whipping effects, they are generally consistent with such effects. Furthermore, one of the players (Shong Nai Yi), who has the most changes in the shoulder and elbow joints, also has the maximum swing speed. (6) Both adult National Team members have better parameters in their torso and upper and lower limb joint speeds, the average and peak speeds of the center of gravity, and the smoothness of the trace of their center of gravity. In particular, during the critical period of swinging the paddle to hit the ball, only one player (Shong Nai Yi) has consistency between her general movement direction and her center of gravity moving direction in the 3D space. This result should be worth the attention of future investigators. Results from the current studies are generally consistent with those previously reported. Table tennis is a special sport that is commonly associated with player variations due to different movement or strike styles. However, based on kinematics parameter analysis of players in action, it is hoped that one can deduce the scientific principles of this sport or find out the meaning or clue of the best movement. If future investigators can use more advanced scientific equipment, software, or combine with studies of training method, these studies will catch the interests of coaches and players and serve as references for future trainings. Keywords: table tennis, forehand drive, kinematics.

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42

Chang, Yu-Hsueh, and 張鈺雪. "Grip force analysis of badminton forehand net kill stroke." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/62457050467859313418.

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Анотація:

碩士
國立臺灣師範大學
體育學系
103
The purpose of this study was to investigate the grip force of the badminton players when they were performed forehand net kill technique. Eight college elite badminton players served as the participants in this study. The palm pressure sensors (Tekscan Grip 4255N) were pasted on the fingers and the palm, Tekscan software was used to collect finger grip force. A Wilcoxon matched-pairs signed-rank nonparametric statistical test was conducted to compare the differences between every two spots in the hands. The results showed there were significant differences in the duration time of the movements with each other. The shortest duration time was the swing phase in the movement (0.07sec), followed by the lift the racket, third for the preparation period, the longest period to follow. The max force of middle finger, index finger, little finger, the second to fourth metacarpal, ring finger and the first metacarpal were generated in the swing phase before impact. In the whole action process, the middle finger, index finger, ring finger and little finger played an important role in controlling force and stabilizing racket. Since the racket compression during the movement, the maximum force was generated after the impact in the fifth metacarpal. Also at the following phase, each knuckle generated the second peak force in order to stabilize the racket.

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43

Huang, Hsin-Hsueh, and 黃信學. "Biomechanical Analysis of Table Tennis Forehand and Backhand Drives." Thesis, 2011. http://ndltd.ncl.edu.tw/handle/15199951154905119222.

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Анотація:

碩士
國立臺灣師範大學
體育學系在職進修碩士班
99
The purpose of this study was to combine the kinematics, kinetics and surface EMG methods to analyze six elite collegiate table tennis players in Taiwan (age: 21 ±4.69 yr, height: 173.5 ±4.59 cm, weight: 67 ±5.80 kg, experience: 12 ±4.52 yr.) when they were performing the forehand and backhand drives techniques while receiving the top spin and the under spin services. Ten VICON MX13+ Motion Capture systems (250 Hz), two KISTLER Force Plates (1500 Hz) and Noraxon Wireless EMG system (1500 Hz) were used to collect the kinematics of the dominate upper limb muscle groups, which were the wrist flexor, wrist extensor, biceps brachii, triceps brachii, pectoralis major, anterior deltoid and posterior deltoid. The EMG data were analyzed by using the Acknowledge software (1000Hz)., kinetics data and surface EMG signal. The Vicon Nexus 1.52 was used to calculate the kinematics and the kinetics data, the Noraxon software was to analyze the EMG signal parameters. All the variables were tested by Friedman two-way analysis of variance nonparametric statistical test, and the post-hoc comparisons were calculated by the Excel software. The Wilcoxon matched-pairs signed-rank nonparametric statistical test was to test the different variables between forehand and backhand drives, the significant level was at α =.05. The results were as follows: there was a significant difference that the forehand drive was greater than backhand drive in the following variables, the return initial velocity of the ball, racket swing velocity, the velocity of center of gravity, racket upswing displacement and the height of center of gravity at the contact point. There was greater racket tilt angle and a lower center of mass when return backspin serve. In ground reaction forces, there was a significant correlation between anteroposterior impulse and horizontal racket anteroposterior velocity. In EMG, The anterior deltoid, pectoralis major, flexor carpi radialis and extensor carpi ulnaris in forehand drives, the posterior deltoid, triceps and extensor carpi ulnaris in back hand drives exerted the greater muscular amplitude during the swing forward phase. There were co-contractions between Biceps Brachii and Triceps Brachii, Flexor carpi radialis and Extensor carpi ulnaris in forehand drives during upswing phase, while a less co-contraction in backhand. The muscular strategy and the patterns of the forehand and backhand drives in elite table tennis players were not the same.

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44

tsai, ya-shih, and 蔡雅詩. "Kinematics Analysis of of badminton forehand and backhand serves." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/z35xmv.

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Анотація:

碩士
國立臺灣師範大學
體育學系在職進修碩士班
97
The purpose of this study was to analyze the kinematical variables of the badminton players when they were performing forehand and backhand serve. Four collegiate elite female badminton players in Taiwan were served as the subjects. Ten Vicon MX-13+ cameras (Vicon, Oxford, UK, 300Hz) were used to record the 3D kinematics data and calculated by Vicon Nexus 1.2 system. The nonparametric statistical test of the Wilcoxon matched-paired signed-rank test between forehand and backhand serve for the differences in kinematics at a .05 significant level. The other way was tested by Friedman analysis of variance nonparametric statistical test which was calculated by SPSS 12.0, and the post-hoc comparison were calculated by the Excel software, the significant levels as α= .05. The result is that in the forehand serving motions of the three different dropping locations, the time of hitting the shuttle is long serve  drive serve  short shot. There are clues in the time of swinging the racket. There are noticeable differences between ulnar flexion of the long serve and drive serve and the short serve of radial flexion. There are noticeable differences between the hitting points and the front or back or left or right distance from the physical center of gravity. In the forehand serving, I suggest to enhance the steadiness of all joints in the twisting forearm because the hitting point is far from the physical center of gravity. If one can fix the angle of the forearm in the process of twisting the body, one can hit the hitting point more correctly. In the backhand serving motions of the three different dropping locations, all depend on the flexion of the wrist.There are also noticeable differences between the hitting points and the front or back distance from the physical center of gravity. In the forehand and backhand serving, I suggest that players enhance the explosive force of the joint of wrist so that at the moment of hitting the shuttle, they can change the force and angle and shorten the time of swinging the racket, which will have an unexpected effect. At the same dropping locations, there are no noticeable differences between forehand and backhand serving of the three different shots. The unclear differences may be caused by only a few data from subjects.

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45

Chen, Yu-Ta, and 陳昱達. "Kinematic analysis of active and passive badminton forehand smashes." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/r4375z.

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Анотація:

碩士
國立臺灣師範大學
體育學系
97
The purpose of this study was to compare the kinematics variables of active and passive badminton forehand smashes. Ten male badminton first level collegiate players were served as the subjects. Ten Vicon MX-13+ cameras (Vicon, Oxford, UK, 250Hz) were used to record the 3D kinematic data and computed by Vicon Nexus 1.3 system. The nonparametric statistical test of the Wilcoxon matched-paired signed-rank test was used to compare the kinematic differences between active and passive forehand smashes at a .05 significant level. The results showed that the initial shuttle velocity during the active smash was greater than the passive smash may due to a better location of contact and the center of gravity (COG) movement, whereas the passive smash performed a shorter movement duration time. There were significant differences between the two smashes in the upper arm angles due to the variation of the posture at striking. Moreover, most of the upper arm angular velocity for the active smash was faster than the passive action. We also found that the internal rotation for the shoulder and the pronation for the wrist were the most important in the two forehand smashes. The trunk with active smash showed greater angular velocity, and seemed to accord with the stretch-shortening cycle (SSC) theory. Therefore, active smash can be beneficial to powerful attack and passive smash can be beneficial to instantaneous attack.

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46

Cheng, Kuang-Chih, and 鄭光志. "Information of badminton forehand shots from dynamic point light display." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/6qja9n.

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Анотація:

碩士
國立臺灣師範大學
體育學系
96
The purpose of this study was to examine the invariant information of badminton forehand shots from dynamic point light data alone. A motion digitizing system (GypsyGyro-18) and a high speed camera (200 Hz) was used to capture 6 forehand strokes of badminton from six badminton elite players and six PE major students. The kinematics data were converted to 15-point of biological motion data including drop, smash and clear shots to both left and right side of the court. Experiment 1: 25 badminton experts and 33 PE major students were recruited to view 144 biological motion clips of the preparatory phase of badminton shots and to identify where the shuttlecock landed. The results showed certain invariant information could be used for both groups, but the percentage of accuracy was low. Furthermore, experts group had better performance in predicting the landing position of the shots, and the depth was more accurately identified than the left-and-right direction. Experiment 2: 12 performers viewed 72 biological motion clips of their complete badminton shots and identified which ones were performed by themselves. The results showed that the performers were unable to identify their own movement and PE group tended to misidentify themselves to be the elites. In conclusion, biological motion can provide invariant information of performance without personal characteristics. The information invariants were provided with the specific mode and affordance also played a role in detecting it.

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47

Huang, Ping-Chang, and 黃炳璋. "Inertia Sensor Applied to Badminton Forehand Drop Shot Vibration Analysis." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/44196797261165698688.

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Анотація:

碩士
樹德科技大學
資訊工程系碩士班
101
Goal: to study to apply the inertia sensor in analyzing the acceleration of badminton forehand drop shots of the female top players. Method: The subjects of the study are ten right-handed National Personal Ranking Competition Badminton players (aged 16.1 ± 2.18 years, height 161.6 ± 3.2 cm, weight 54.9 ± 3.14 kg, ball age 7.5 ± 2.17 years). The study applied wireless inertial sensor (including triaxial accelerometers, the sampling frequency is 3333Hz) on experimental rackets, and with a high-speed camera and speed gun to retrieve the information of the racket vibration when the players repeatedly hit the ball 20 times, and used frequency domain analysis, time domain analysis, vibration time, ball points to analyze the statistical differences. Result： 1.The study found that there was no significant difference in t-test when the same player used the racket was with or without inertial sensors. 2.There was a significant difference that the ball speed of the best players were faster than that of the second best players. 3.To compare the racket amplitude frequency spectrum analysis, the average of the best players’ batting point in appropriate areas was more than seven times, which was significantly stabler than the second best players. 4.In the spectrum analysis, in the Y-axis direction (lateral direction), the best players had more amplitude in 78~156Hz but the second best players did not. In the Z-axis direction (forward direction), the best players had more amplitude in 78~195 Hz but the second best players did not. 5.There were significant differences between the best players and second players in the frequent area analysis of the maximum, average, total rated power of the racket acceleration. 6.There was a significant difference that in the racket vibration time in three axises , the best players’ was lower than the second best players’. 7.There were significant differences between the best players and second best players in the time-domain analysis of the maximum, average, total rated power of the racket acceleration in triaxial and the values of the best players were greater than them of the second best players. 8.The Pitch angle (ρ ) for the best players refers to 12.29 and that for the second best players refers to 12.04. There is little difference. As for the Roll (ϕ) angle, their performance refers to 55.01 and 47.45 respectively. There is substantial difference. As for Theta (θ) angle, their performance refers to 56.81 and 59.3 respectively. There is little difference. Conclusion： 1.The Racket with wireless inertial sensors would not affect the player’s hitting performance. 2.There was a significant difference that the ball speed of the best players was faster than the second best players. 3.In the X-axis and Z-axis, the vibration frequency of the best players was more obvious than that of the second best players. In the Y-axis, there was no obvious vibration frequence among the best and second best players. 4.The best players would loosen the grip of the racket after hitting balls, while the second best players would not. 5.There were significant differences between the best players and the second best players in the maximum, average, total power rate of the racket acceleration, and the X-axis direction (upward direction) was the most differently valued. 6.The study found that from the X-axis and Z-axis, in the hitting process, the best players accelerated the pressing down faster than the second best players did. Suggestion： The analysis of the experimental data about the X-axis and Z-axis acceleration and angle when hitting balls may offer relevant information and modals to professional coaches for training players in the future.

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48

SU, YI-SHEN, and 蘇依審. "Effects of Teaching Methods on Tennis beginners Forehand/Backhand Performance." Thesis, 2017. http://ndltd.ncl.edu.tw/handle/21444659090768413647.

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Анотація:

碩士
中國文化大學
體育學系運動教練碩博士班
105
This study mainly discusses about two different teaching methods including fun and traditional. According to different curriculum design patterns, we can find out the differences between satisfaction and skills of students. In this study, 40 tennis beginners from Grade 7 of National High School in Taipei were selected as experimental group. The tennis skill test and the tennis learning satisfaction were used as the tools. The students were divided into two groups by random sampling. One group is the fun of teaching group, and the other group is the traditional teaching group. After eight weeks of experimental teaching, we can see the test scores for the learning effect before and after teaching. With independent samples and dependent samples T test statistical analysis, the results are summarized as follows: First, the students in the fun group had significant differences in boring sensation, but the traditional group did not reach significant differences. The fun group felt more enjoy than the traditional group in learning. Second, the learning skills of students in both fun and traditional group were significantly different. Fun and traditional groups’ forehand stroke were significant differences, while the backhand strokes’ were not significant differences. The fun group learned better than the traditional group.

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49

Chiang, Shao-Chun, and 江少鈞. "The Inverse Dynamic and Kinematic Analysis During Forehand in Soft Tennis." Thesis, 2009. http://ndltd.ncl.edu.tw/handle/16052316134105248639.

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碩士
臺北巿立體育學院
運動科學研究所
97
The aim of this research was to investigate the kinematic parameters of upper joint of soft tennis players during forehand swing and using dynamics and inverses dynamics to calculate the horizontal, vertical force and net muscle torque of upper limbs (wrist, elbow and shoulder joint) during the process of forehand hitting. The participators of this study were five elite collage soft tennis players, using two high speed cameras (500Hz) and motion software to analyze kinematic parameters of player swinging and applied inverses dynamics to calculate the force and torque of upper joints. The result of this research was showing some subjects: 1. The kinematic parameters of upper joint were faster from shoulder to wrist joint to be whipping effect. 2. The swinging motion was expectably coincident with the stroking pattern of the subjects. 3. In the inverses dynamic analysis showed that the shoulder joint had the bigger power than other two joints of ball stroking.

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50

Wei, Chun-Ta, and 魏君達. "An analysis of the motion of forehand loop in table tennis." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/89056170983040153899.

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碩士
國立臺灣體育大學(桃園)
運動技術研究所
96
The purpose of the study was to evaluate the motion of skills of fore-hand loop of elite table tennis players. The subjects of the study were eleven male national grand master athletes of table tennis in R.O.C. The study method was that we videoed players’ motions of fore-hand loop to returned back-spin ball, then decomposed the continual movie to serial pictures for analysis and commented subjectively by four raters, with the rater reliability 0.865, on those data of each player’s skills of fore-hand loop. By the main study of quantities and characters of their motions, the results we achieved were as follows. (1) There were twelve items of common important key point of the motion of skills of fore-hand loop of those eleven players. (2) On other seven items, there were inconsistent skill motions characteristics with individual players. The conclusions of the study were that within the nineteen items the motion of skills of fore-hand loop, there were twelve items the motion of skills of fore-hand loop should be correctly performed by elite table tennis players. Few inconsistent the motion of skills should be the key points that owing to the player’s physical condition, striking method and position.

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