Dissertations / Theses: 'Human Postural Analysis'

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Celik, Huseyin. "Linear And Nonlinear Analysis Of Human Postural Sway." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12609927/index.pdf.

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Human upright posture exhibits an everlasting oscillatory behavior of complex nature, called as human postural sway. Variations in the position of the Center-of-Pressure (CoP) were used to describe the human postural sway. In this study
CoP data, which has experimentally been collected from 28 different subjects (14 males and 14 females with their ages ranging from 6 to 84), who were divided into 4 groups according to their ages has been analyzed. The data collection from each of the subjects was performed in 5 successive trials, each of which has lasted for 180-seconds long. Linear analysis methods such as the variance/standard deviation, Fast Fourié
r Transformation, and Power Spectral Density estimates were applied to the detrended CoP signal of human postural sway. Also the Run test and Ensemble averages methods were used to search for stationarity and ergodicity of the CoP signal respectively. Furthermore, in order to reveal the nonlinear characteristics of the human postural sway, its dynamics were reconstructed in m-dimensional state space from the CoPx signals. Then, the correlation dimension (D2) estimates from the embedded dynamics were calculated. Additionally, the statistical and dynamical measures computed were checked against any significant changes, which may occur during aging. The results of the study suggested that human postural sway is a stationary process when 180-second long biped quiet stance data is considered. In addition, it exhibits variable dynamical structure complex in nature (112 deterministic chaos versus 28 stochastic time series of human postural sway) for five successive trials of 28 different subjects. Moreover, we found that groups were significantly different in the correlation dimension (D2) measure (p&
#8804
0.0003). Finally, the behavior of the experimental CoPx signals was checked against two types of linear processes by using surrogate data method. The shuffled CoPx signals (Surrogate I) suggested that temporal order of CoPx is important
however, phase-randomization (Surrogate II) did not change the behavioral characteristics of the CoPx signal.

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Safi, Khaled. "Human postural stability analysis : application to Parkinsonian subjects." Thesis, Paris Est, 2016. http://www.theses.fr/2016PESC1066/document.

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L’analyse de la stabilité posturale chez l’homme a fait l’objet, ces dernières années, d’un intérêt grandissant au sein de la communauté scientifique. Le système postural permet de maintenir la stabilité du corps humain en posture statique ou dynamique. Cette capacité à maintenir cette stabilité devient critique dans le cas des sujets Parkinsoniens. La maladie de Parkinson a en effet une forte incidence sur la stabilité posturale. Un moyen efficace pour évaluer l’équilibre postural consiste à analyser les déplacements dans le plan horizontal du centre de pression du corps humain en posture orthostatique ; les trajectoires mesurées dans la direction medio-latérale (ML) et la direction Antéro-postérieure (AP) sont appelées signaux stabilométriques. Dans cette thèse, nous visons le développement de méthodes efficaces pour l’analyse de l’équilibre en posture orthostatique sous différentes conditions liées à l’entrée visuelle (yeux ouverts/yeux fermés), la position des pieds (pieds joints/pieds écartés) et en considérant d’autres facteurs comme le genre et l’âge. Dans ce cadre, nous proposons, tout d’abord, une méthode exploitant la variante EEMD (Ensemble Empirical Mode Decomposition) de la décomposition en modes empiriques (EMD) et l’analyse de la diffusion du stabilogramme. Dans le contexte du diagnostic de la maladie de Parkinson, la discrimination entre sujets sains et sujets Parkinsoniens est très importante, de même que l’évaluation du stade de la maladie pour les sujets atteints. Dans ce cadre, deux méthodes sont proposées. La première consiste tout d’abord en une extraction et sélection de caractéristiques temporelles et spectrales, à partir des signaux stabilométriques brutes ou des modes de fonctions intrinsèques dérivés de la décomposition EEMD. Des méthodes standards de type KNN, CART, RF et SVM sont ensuite appliquées pour reconnaitre les sujets Parkinsoniens. La deuxième méthode proposée, est une approche de classification qui repose sur l’emploi de HMMs construits en utilisant les signaux stabilométriques brutes dans les directions ML, AP et ML/AP. Enfin, une dernière méthode est proposée pour la segmentation automatique des signaux stabilométriques sous différentes conditions (entrée visuelle, position des pieds). Pour ce faire, un modèle de régression régi par une chaine de Markov cachée (HMMR) est utilisé pour détecter automatiquement les variations des structures des signaux stabilométriques entre ces conditions. Les résultats obtenus montrent clairement la supériorité des performances des méthodes proposées par rapport aux approches standards, aussi bien, en termes d’analyse de l’équilibre postural que de diagnostic de sujets Parkinsoniens
Recently, human balance control analysis has received an increasing interest from the research community. The human postural system maintains the stability of the body both in the static posture (quiet standing) and during locomotion. This ability to maintain stability becomes hard with aging and Parkinson's disease (PD) subjects. PD has a strong effect on postural stability during quiet standing situations, and during locomotion. One effective way to assess human stability is to analyze the center of pressure (CoP) displacements of the human body during quiet standing. The recorded CoP displacements in quiet standing are called stabilometric signals. This thesis aims to develop efficient approaches to analyze the human postural stability in quiet standing under visual and feet position conditions, as well as under age and gender. This is achieved using Empirical Mode Decomposition (EMD) method and stabilogram-diffusion technique. In the other part, the discrimination between healthy and PD subjects is very important for diagnosing Parkinson's disease, as well as for evaluating the disease level of the patient. In this context, two approaches are proposed; the first approach consists of an EMD-based temporal and spectral feature extraction from the stabilometric signals. The second approach is based on a Hidden Markov Model (HMM) using the raw stabilometric signals. The HMM model is an efficient tool to analyze temporal and sequential data. Another approach is proposed in order to segment the stabilometric signals according to the visual and feet position conditions. This is achieved using a Hidden Markov Model Regression (HMMR)-based approach. This study help clinicians to better understand the motor strategies used by the subjects during quiet standing and may guide the rehabilitation process. The obtained results clearly show high performances of the proposed approaches with respect to other standard approaches in both postural stability analysis and discrimination healthy from PD subjects

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Siegrist, Kyle W. "Diagnostic Analysis of Postural Data using Topological Data Analysis." Miami University / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=miami1564748543676698.

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NAGA, SOUMYA. "AN EFFICIENT ALGORITHM FOR CLINICAL MASS CENTER LOCATION OF HUMAN BODY." University of Cincinnati / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1131323551.

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Larson, Michael Andrew. "A Progressive Refinement of Postural Human Balance Models Based on Experimental Data Using Topological Data Analysis." Miami University / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=miami159620428141697.

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Aws, Ghassan. "Analysis of symmetry in the anterior human dentition and its application in the evaluation and correction of postural distortion in the photographic recording of human bite marks." Thesis, University of Edinburgh, 2006. http://hdl.handle.net/1842/1348.

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Postural distortion of human bite marks on skin occurs when photographing a bite mark in a body position other than the position of the body at the time of biting. Postural distortion in the bite mark may introduce significant changes in both the shape and size of the recorded marks. As a result, the analysis of the marks may be hindered and a proper comparison between the bite mark and the causal dentition may be precluded. Therefore, a method by which postural distortion in a bite mark photographic record can be evaluated and eliminated with minimal operator subjectivity is required. This study describes the development of an objective technique for evaluating postural distortion in bite mark photographic records and for minimising postural distortion during photography of bite marks. The source for developing these techniques was provided by digitally analysing the symmetry of dental arches in a defined population including males and females (236 subjects) whose ages ranged between 20 and 30 years. The analysis resulted in quantifying a mathematical relationship between the biting edges of each homologous pair of the anterior teeth and specified reference lines. The validity of the analytical method of dental arch symmetry is discussed. The developed techniques were applied to posturally distorted (test) bite marks. The results demonstrate the validity of the developed techniques in determining postural distortion and recording correct images (shown to resemble the biters dentition) of the test bites. Suggestions for further work are proposed.

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Mikov, Nikolay. "A distributive approach to tactile sensing for application to human movement." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/11608.

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This thesis investigates on clinical applicability of a novel sensing technology in the areas of postural steadiness and stroke assessment. The mechanically simple Distributive Tactile Sensing approach is applied to extract motion information from flexible surfaces to identify parameters and disorders of human movement in real time. The thesis reports on the design, implementation and testing of smart platform devices which are developed for discrimination applications through the use of linear and non-linear data interpretation techniques and neural networks for pattern recognition. In the thesis mathematical models of elastic plates, based on finite element and finite difference methods, are developed and described. The models are used to identify constructive parameters of sensing devices by investigating sensitivity and accuracy of Distributive Tactile Sensing surfaces. Two experimental devices have been constructed for the investigation. These are a sensing floor platform for standing applications and a sensing chair for sitting applications. Using a linear approach, the sensing floor platform is developed to detect centre of pressure, an important parameter widely used in the assessment of postural steadiness. It is demonstrated that the locus of centre of pressure can be determined with an average deviation of 1.05mm from that of a commercialised force platform in a balance application test conducted with five healthy volunteers. This amounts to 0.4% of the sensor range. The sensing chair used neural networks for pattern recognition, to identify the level of motor impairment in people with stroke through performing functional reaching task while sitting. The clinical studies with six real stroke survivors have shown the robustness of the sensing technique to deal with a range of possible motion in the reaching task investigated. The work of this thesis demonstrates that the novel Distributive Tactile Sensing approach is suited to clinical and home applications as screening and rehabilitation systems. Mechanical simplicity is a merit of the approach and has potential to lead to versatile low-cost units.

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Ringhof, Steffen [Verfasser]. "Effects of Concurrent Jaw Clenching on Human Postural Control and Sports Performance: Biomechanical Studies of Static and Dynamic Postural Control and Performance Analysis in Golf / Steffen Ringhof." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1159637547/34.

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MARCHESE, SILVIA MARIA. "CONTRIBUTION OF BASAL GANGLIA, CEREBELLUM AND PARIETAL OPERCULUM TO ANTICIPATORY POSTURAL ADJUSTMENTS." Doctoral thesis, Università degli Studi di Milano, 2020. http://hdl.handle.net/2434/695700.

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Anticipatory Postural Adjustments (APAs) are a crucial aspect of the voluntary movement organization, being fundamental in stabilizing both the whole-body (inter-limb APAs) and its segments (intra-limb APAs). Until now, only a few works investigated the neural structures involved in APAs programming, by correlating neurological diseases with APAs changes. This approach clarified not only the knowledge regarding these pathologies, but also the relationships between these structures and the APA command. So, to enrich the comprehension about the neural network generating and influencing APAs, this thesis is focused on two aspects. The first part investigated the role of two subcortical structures, basal ganglia and cerebellum, in APAs organization. In particular, it was analyzed (i) how intra-limb APAs stabilize the arm and the forearm, when flexing the index-finger, in patients with basal ganglia dysfunction, as well as (ii) the inter-limb APAs associated to gait initiation in children with cerebellar ataxia. Results showed that basal ganglia seem to be involved in APA control, since the normal pattern of intra-limb APAs is disrupted in parkinsonian patients. On the other hand, the role of the cerebellum as a timing-machine was confirmed, since several alterations were found in the temporal organization of inter-limb APAs in ataxic vs. healthy children. Considering recent studies showing that basal ganglia and cerebellum are reciprocally interconnected and that the cerebellum exerts a functional compensatory activity in parkinsonian patients, it could be interesting to address future studies to inquire a reciprocal compensatory role of basal ganglia in cerebellar disease. The second part dealt with the possible influence of cognitive processes on APA control. To achieve this goal, a cerebellar area with a well-known cognitive role, Crus I-II, was examined. In this context, a protocol of Magnetic Resonance Spectroscopy was developed, able to characterize and quantify metabolites in a cerebellar area of interest. The protocol was validated in healthy subjects and could be used in future investigations of neurological diseases affecting postural and motor control. Finally, the Parietal Operculum (PO) activity was studied. This is a cortical sensory-motor integration center, notably involved in a multimodal network. So, intra-limb APAs associated to index-finger flexion were analyzed in healthy subjects before, during and after modulating the contralateral PO (coPO) excitability by anodal and cathodal transcranial Direct Current Stimulation (tDCS). Since no significant effects were found on intra-limb APAs amplitude and timing, the coPO does not seem to be involved in APA control. However, future studies should address the possible influence of both POs by bilateral tDCS.

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Taylor, Melissa Rose. "The Effect of Input Parameters on Detrended Fluctuation Analysis of Theoretical and Postural Control Data: Data Length Significantly Affects Results." University of Dayton / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=dayton1448879109.

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Yin, ChengXin. "Predictive Simulation for the Design of Robotic Device for Mobility-Aid." Electronic Thesis or Diss., Bourges, INSA Centre Val de Loire, 2020. http://www.theses.fr/2020ISAB0007.

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Dans cette thèse, nous avons proposé une méthodologie pour aider dans la conception d'un exosquelette robotique. En effet, le travail principal est d'aider le concepteur à sélectionner les comportements dynamiques adéquats des mouvements induit par un exosquelette pour une personne à mobilité réduite. En ajustant les paramètres de chaque actionneur, les tâches de mouvement humain peuvent être assistées par l'application d'une aide à la mobilité robotisée via une interaction hommerobot. Il n'y aura qu'un seul groupe de paramètres d'actionneurs les plus appropriés créés par optimisation pour une locomotion humaine particulière. Sur la base des résultats optimisés, nous sommes en mesure d'interpréter l'interaction homme-robot pour proposer une conception de variables de contrôle pour une tâche de mouvement spécifiée. La première étape de cette méthode consiste à mettre en œuvre la modélisation neuromusculosquelettique (NMS) et la simulation, pour mieux décrire les caractéristiques dynamiques humaines. Cette étape peut illustrer les natures physiologiques du corps humain sous la forme de «Actionneur Musculaire - Accélération -Trajectoire» pendant une période de mouvement. Par exemple, on peut rechercher la fonction des muscles dans l'actionnement de la locomotion humaine grâce à une simulation de la poursuite de trajectoire. En outre, des cas de simulation ont été créés pour évaluer de nouveaux mouvements et adaptations à différentes conditions. La mise en œuvre de la simulation prédictive le rend possible: ce quiconstitue également la deuxième étape de notre étude. Pour réaliser les prédictions, elles doivent d'abord formuler notre problèmes de contrôle optimal puis le résoudre par des algorithmes numériques. Une interface de programmation applicable (API) àOpenSim-Matlab a été utilisée pour intégrer un solveur numérique et discrétiser les problèmes et résoudre les processus. Ces propositions ont été validées via une étude de cas d'aide à la mobilité robotique, le système humainESTA. ESTA est un exosquelette conçu pour compenser les degrés de liberté (DOF) du bras de l'utilisateur. L'humanoïde NMS a été modélisé comme un membre supérieur d'un côté. Les effets d'interaction entre l'humain et le dispositif ont été considérés comme les actionneurs virtuels équivalents qui fournissent des forces et moments ajustés pour des articulations humaines particulières. Un problème de contrôle optimal a été formulé pour représenter les simulations prédictives. Ensuite, nous avons également testé une variété de variables de contrôle optimales afin de prédire les situations «What if» . Des données expérimentales ont été collectées pour valider les systèmes ainsi que pour fixer les trajectoires référencées aux prédictions. Les résultats montrent que notre méthode pour proposer un modèle d'actionnement pour un exosquelette robotique est prometteuse et permet de préciser le mouvement humain par une tâche donnée
In this thesis, we have proposed a methodology on design of the robotic exoskeleton. The main work is to help the designer to select adequate dynamical behaviors of the movements induced by an exoskeleton for a person with reduced mobility. Hence by adjusting the parameters for each actuator, the human motion tasks can be assisted by the robotic mobilityaid application via human-device interaction. There is only one group of the most suitable actuator parameters created via optimization for a particular human locomotion. Based on the optimized results, we are able to interpret the human-device interaction as well as to propose the design of control variables for a specified motion task. The first stage of this method consists of the implementation of the neuromusculoskeletal (NMS) modeling and simulation, which is for better describing the human dynamical characteristics. This stage can illustrate the physiological natures of human bodies in the form of 'Muscular ActuatorAcceleration-Trajectory' during a period of motion. For instance, one can search the function of muscles in actuating human locomotion through a motion-tracking simulation. Besides, the 'what if' cases were created to evaluate novel movements and adaptions to different conditions. The implementation of predictive simulation makes it feasible : which also constitutes thesecond stage of our study. To fulfill the predictions, we have to formulate our problems as optimal control processes and then solve them by numerical algorithms. Here, an OpenSimMatlab applicable programming interface (API) was modeled to embed a numerical solver and discretize the problems and solve the processes. These propositions have been validated via a case-study of robotic mobility-aid, the human-ESTA system. ESTA is an exoskeleton designed for compensating degrees-of-freedom (dofs) of the user's arm. The NMS humanoid was modeled as one-side upper extremity limb. Interaction effects between the human and device were considered as the equivalent virtual actuators which provide adjusted forces and moments for particular human joints. An optimal control problem was set to represent the predictive simulations. We also tested a variety of the optimal control variables in order to predict the 'what if' situations. Experimental data were collected for validating the systems as well as setting the referred trajectories to the predictions. Results showthat our method for proposing an actuating pattern for a robotic exoskeleton is promising and allowed to specify the human movement for a given task

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Durango, Melisa de Jesus Barrera. "SIRAH : sistema de reconhecimento de atividades humanas e avaliação do equilibrio postural /." Ilha Solteira, 2017. http://hdl.handle.net/11449/151317.

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Orientador: Alexandre César Rodrigues da Silva
Resumo: O reconhecimento de atividades humanas abrange diversas técnicas de classificação que permitem identificar padrões específicos do comportamento humano no momento da ocorrência. A identificação é realizada analisando dados gerados por diversos sensores corporais, entre os quais destaca-se o acelerômetro, pois responde tanto à frequência como à intensidade dos movimentos. A identificação de atividades é uma área bastante explorada. Porém, existem desafios que necessitam ser superados, podendo-se mencionar a necessidade de sistemas leves, de fácil uso e aceitação por parte dos usuários e que cumpram com requerimentos de consumo de energia e de processamento de grandes quantidades de dados. Neste trabalho apresenta-se o desenvolvimento do Sistema de Reconhecimento de atividades Humanas e Avaliação do Equilíbrio Postural, denominado SIRAH. O sistema está baseado no uso de um acelerômetro localizado na cintura do usuário. As duas fases do reconhecimento de atividades são apresentadas, fase Offline e fase Online. A fase Offline trata do treinamento de uma rede neural artificial do tipo perceptron de três camadas. No treinamento foram avaliados três estudos de caso com conjuntos de atributos diferentes, visando medir o desempenho do classificador na diferenciação de 3 posturas e 4 atividades. No primeiro caso o treinamento foi realizado com 15 atributos, gerados no domínio do tempo, com os que a rede neural artificial alcançou uma precisão de 94,40%. No segundo caso foram gerados 34 ... (Resumo completo, clicar acesso eletrônico abaixo)
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Pettersson, Robert. "Human Postures and Movements analysed through Constrained Optimization." Licentiate thesis, Stockholm : Skolan för teknikvetenskap, Kungliga Tekniska högskolan, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-10682.

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Silva, Cristiano Rocha da. "Estudo multivariável do controle postural humano em resposta a pistas sensoriais somestésicas." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/47/47135/tde-05012017-104731/.

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Todo ser humano apresenta oscilações posturais aleatórias durante a postura ereta quieta advindas de mecanismos centrais e periféricos. Um toque suave (LT do inglês light touch) de um dos dedos sobre uma superfície fixa ao solo resulta em uma pista sensorial adicional, que promove uma diminuição das oscilações posturais. Entretanto, há necessidade de se obter maiores conhecimentos sobre mecanismos associados ao LT, tanto no que tange a aspectos sensoriais quanto motores associados ao fenômeno. O presente estudo teve como objetivo avançar no entendimento sobre a influência do LT sobre o comportamento de múltiplas variáveis extraídas durante a postura ereta quieta. O primeiro capítulo investigou quantificadores de oscilações posturais com base em medidas como o centro de pressão (CP), centro de massa (CM) e ângulos segmentares e corporais durante experimentos com condições em superfície estável e instável, com olhos abertos e olhos fechados, comparando as condições com e sem LT. Adicionalmente, foi analisada a coerência espectral entre sinais de eletromiograma de diferentes músculos do corpo e os quantificadores acima elencados nas diferentes condições. Os resultados mostraram que o LT diminui o nível de ativação de alguns músculos, principalmente o músculo gastrocnêmico medial, importante na manutenção do controle postural. A variabilidade dos ângulos segmentares e corporais, conjuntamente com variáveis extraídas do CP e do CM diminuíram em condições com LT. Na análise de coerência o LT promoveu algumas alterações nos padrões de oscilação entre ângulos, CP, CM e sinais de eletromiograma, porém com poucas modificações na fase entre os sinais. Na análise de coerência intermuscular, comparando pares de músculos do lado direito e esquerdo do corpo, observou-se que para os membros inferiores a coerência ocorre geralmente na faixa de 0 a 1-2 Hz (em fase), podendo aumentar a faixa de frequência em situações mais instáveis (sem visão e superfície instável), em que o LT passa a influenciar de maneira mais significativa a coerência entre os sinais. O segundo capítulo deste estudo foi motivado por estudos que mostraram ser possível manipular as entradas sensoriais geradas pelo dedo durante o LT. O presente estudo investigou se a retirada de uma entrada sensorial proprioceptiva associada ao dedo é capaz de alterar a oscilação postural, possibilitando a separação e quantificação da contribuição sensorial cutânea da contribuição proprioceptiva dos músculos do terceiro dedo. O controle postural foi avaliado com os sujeitos de olhos fechados e sobre uma superfície instável. Os resultados indicaram que a retirada da informação sensorial proprioceptiva do dedo diminuiu a variabilidade e a velocidade do CP, indicando que a informação cutânea sem a adição de interferências proprioceptivas pode diminuir as oscilações posturais
Human subjects during upright stance show random postural oscillations which are controlled by the central nervous system. A light touch of an index finger (LT) on a surface fixed to the ground results in an additional sensory cue, which promotes a decrease in postural oscillations. However, there is a need to improve the knowledge about mechanisms associated with LT, both with respect to sensory and motor aspects associated with the phenomenon. This study aimed to further the understanding of the influence of LT on the behavior of multiple variables measured during upright stance. The first chapter analyzed variations of some quantifiers of postural sway based on the center of pressure (CP), center of mass (CM) and joint and body angles during experiments with different surface and vision conditions, with and without LT. In addition, the spectral coherence was analyzed between electromyogram signals from different muscles of the body and the previously listed sway quantifiers. The results showed that LT decreases the level of activation of some muscles, particularly the medial gastrocnemius, an important muscle for the maintenance of posture. Segmental and body angle variability and variables extracted from the CP and CM decreased in conditions with LT. In coherence analysis LT promoted some changes in patterns of oscillation between angles, CP, CM and EMGs, but with few modifications in the phase between the signals. The intermuscular coherence analysis (comparing the right and left muscles pairs of the body) showed that significant changes usually occured in the range of 0 to 1-2 Hz (in phase) for the lower limbs and may increase the frequency range in unstable situations (without vision and unstable surface). In these cases LT starts to affect more significantly the coherence between signals. The second chapter of this study was motivated by results from studies that have shown that it is possible to manipulate the sensory inputs generated by the finger during LT. This study investigated whether the withdrawal of a finger proprioceptive input affects postural sway, allowing an analysis of the effects of cutaneous sensory inputs of the third finger muscles. Postural control was evaluated with the subjects with the eyes closed and on an unstable surface. The results showed that removal of proprioceptive information from the finger flexor muscles decreased the variability and speed of the CP, indicating that cutaneous inputs without proprioceptive information may decrease postural sway

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PALAZZO, ALICE. "From standing posture to vertical jump - Experimental and model analysis of human movement." Doctoral thesis, Università degli studi di Genova, 2019. http://hdl.handle.net/11567/942312.

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Cuarelli, Gilberto. "Implementação de novas tecnologias para a avaliação do controle postural e análise da marcha humana /." Guaratinguetá, 2018. http://hdl.handle.net/11449/181013.

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Orientador: José Celso Freire Junior
Resumo: Algumas necessidades específicas da Fisioterapia, área que estuda o Equilíbrio Postural e a Análise da Marcha Humana estão entre as principais razões para o desenvolvimento deste trabalho de pesquisa. Ele, tem por base uma plataforma de força, desenvolvida em 2016 por pesquisadores da UNESP e do Laboratório G-SCOP, da instituição Grenoble INP da França. A esta solução foram adicionadas duas interfaces eletrônicas. A primeira, com objetivo de fornecer informações sobre as forças de reação do solo, de um paciente que está sobre a plataforma e a segunda para controlar a estabilidade da plataforma, simulando dois níveis de dificuldades para o paciente se manter em equilíbrio. Aplicativos foram desenvolvidos para fazer a captura de dados e a análise gráfica dos resultados. Além de calcular informações sobre o deslocamento dos centros de pressão e de massa do paciente, eles asseguram o sincronismo entre os dados capturados por sensores de força, instalados na plataforma e um sensor de movimento Kinect. O tratamento dos dados do sensor de movimento possibilita a criação de um modelo tridimensional detalhado, na forma de um esqueleto digital, que apresenta a cinemática de várias articulações do corpo humano e o seu respectivo comportamento posicional, em função do tempo. O trabalho apresenta também um estudo comparativo entre o sistema desenvolvido e um ambiente de referência padronizado, que utiliza um sistema de filmagem, com várias câmeras infravermelho de alta definição, disponív... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Some specific needs of Physiotherapy, an area that studies the Postural Equilibrium and the Gait Analysis are among the main reasons for the development of this research work. It is based on a force platform, developed in 2016 by researchers from UNESP and the G-SCOP Laboratory of the Grenoble INP institution in France. Two electronic interfaces were added to this solution. The first one, to provide information about the ground reaction forces, from one patient on the platform and the second to control the stability of the platform, simulating two levels of difficulty for the patient to keep in balance. Applications were developed to capture data and graphically analyze the results. In addition to calculating information about the displacement of the patient's pressure and mass centers, they ensure synchronization between the data captured by force sensors installed on the platform and a Kinect motion sensor. The treatment of motion sensor data allows the creation of a detailed three-dimensional model, in the form of a digital skeleton, which presents the kinematics of various joints of the human body and their respective positional behavior, as a function of time. The work also presents a comparative study between the developed system and a standardized reference environment, using a multi-camera high-definition infrared camera system, available in a dedicated room of the University Hospital of Grenoble. This analysis evaluates the possibility of creating new products for th... (Complete abstract click electronic access below)
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Zhang, Li. "Human animation from analysis and reconstruction of human motion in video sequences." Thesis, Curtin University, 2009. http://hdl.handle.net/20.500.11937/684.

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This research aims to address one of the most challenging problems in the field of computer vision and computer graphics, that is, the reconstruction of smooth 3D human motions from monocular video containing unrestricted human movement. The objective is to propose novel methods which differ from the traditional kinematics/dynamics formulations and image based reconstruction methods to provide an alternative highly automated way for human animation from the most widely available source that records human movements and activities. Such methods should be relatively low-cost while avoiding many limitations that come up with current motion tracking equipment.Monocular images or video sequences are chosen as the source of the project, due to the fact that they are widely available through many ways, such as film making and even simple home videos. Most of such monocular images or video sequences are generally uncalibrated, i.e., the information on the camera from which these images are taken is not available. In addition, although 2D joint locations and body silhouettes can be extracted from the images, accuracy of such 2D feature extractions may not be satisfactory by current image processing techniques. Using such monocular image sequence as the input source, many techniques and algorithms are proposed in this research.A 3D skeletal human model based on human anatomy is constructed with angular constraints encoded in the joints according to the biomechanical and physiological knowledge. The model is simple and yet sufficient to simulate realistic human motions, while the computational expense is much lower when dealing with skeletal model than with any other human models. Relative lengths of every body part of the human model are adjusted to be consistent with the human subject in the source images before reconstruction. That is achieved by preciously acquired geometry information on the human subject of interest.A Motion Trend Analysis (MTA) method is proposed in this research to automatically reconstruct the 3D postures of the human subject of interest directly from the extracted 2D joint locations (with possible noise tolerance) at each image frame. This method utilized the information on previously reconstructed postures to assist positioning the joints of the human model to their proper 3D locations in the current frame. To ensure a reliable starting point in the reconstruction, manual adjustment may be required to improve the accuracy of the first three posture recoveries. 3D positional coherence of every joint between adjacent recovered postures can be obtained and maintained at a satisfactory level. Objective Function (OF) is defined to represent the 2D residuals between the extracted feature points and the corresponding features resulted from projecting the reconstructed human model to the projection plane. The OF also includes considerations of all 3D positional discrepancies at every joint between adjacent postures. By translating the pelvis joint and rotating each joint of the human model, a proper human posture that resembles the one represented in the monocular image can be created by searching for the minimum value of the OF. To balance 2D residuals and 3D discrepancies, weighting parameters (WP) determination routine was developed which is able to dynamically adjust the WP values for the 2D and 3D factors in an OF.3D acquisition of smooth and reasonable human motion is the main focus of this research. Such human motions are in high demand for applications involving virtual human movements. A Motion Level Control (MLC) algorithm was proposed to be integrated with the MTA system to further ensure the rotational coherence of the reconstruction results in 3D and improve the efficiency of the search process. Application of MLC can be divided into two modules: the relocation of the pelvis joint and the recoveries of the skeleton segments rotations. Based on MLC, the computational cost of the search procedure for the pelvis relocation and the skeleton adjustment in the human posture recovery will be significantly reduced. At the same time, rotational consistency of each body segment in the reconstructed motion can reach a satisfactory level. Experimental results from the proposed algorithm are highly satisfactory.This research also attempts to acquire smooth yet reasonable 3D human motions from the monocular images with body occlusion or based on extracted silhouettes. Existing techniques for recovering human postures usually require as input a human motion sequence where every body segment is visible at all time. Such requirement might not always be satisfied. The human motion to be reconstructed could contain occlusions where part or the body is obscured by other object in the scene or by another part of the human body itself. The input video could also be not clear enough to provide acceptable 2D joint extractions. This research extends the developed MTA and MLC and proposes novel methods to acquire the smooth and reasonable human postures under such circumstances. Experiments have produced very promising results.There are still many challenges ahead, especially on the preprocessing of the monocular images such as the accurate extraction of joint locations and fullyautomatic posture recoveries. Besides, the Objective Function and biomechanical constraints should be further studied to improve the general performance of the motion reconstruction system. Human motion reconstruction algorithm without accurate 2D inputs in terms of joint features or silhouettes should also be explored. The human motion reconstruction obtained from this research currently can handle 2D input with minor extraction errors. A more applicable system that can tolerate more input errors will be highly desirable and hence should attract some research attention. Technical issues to be explored and addressed in the future are identified and discussed in this thesis.

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Neverova, Natalia. "Deep learning for human motion analysis." Thesis, Lyon, 2016. http://www.theses.fr/2016LYSEI029/document.

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L'objectif de ce travail est de développer des méthodes avancées d'apprentissage pour l’analyse et l'interprétation automatique du mouvement humain à partir de sources d'information diverses, telles que les images, les vidéos, les cartes de profondeur, les données de type “MoCap” (capture de mouvement), les signaux audio et les données issues de capteurs inertiels. A cet effet, nous proposons plusieurs modèles neuronaux et des algorithmes d’entrainement associés pour l’apprentissage supervisé et semi-supervisé de caractéristiques. Nous proposons des approches de modélisation des dépendances temporelles, et nous montrons leur efficacité sur un ensemble de tâches fondamentales, comprenant la détection, la classification, l’estimation de paramètres et la vérification des utilisateurs (la biométrie). En explorant différentes stratégies de fusion, nous montrons que la fusion des modalités à plusieurs échelles spatiales et temporelles conduit à une augmentation significative des taux de reconnaissance, ce qui permet au modèle de compenser les erreurs des classifieurs individuels et le bruit dans les différents canaux. En outre, la technique proposée assure la robustesse du classifieur face à la perte éventuelle d’un ou de plusieurs canaux. Dans un deuxième temps nous abordons le problème de l’estimation de la posture de la main en présentant une nouvelle méthode de régression à partir d’images de profondeur. Dernièrement, dans le cadre d’un projet séparé (mais lié thématiquement), nous explorons des modèles temporels pour l'authentification automatique des utilisateurs de smartphones à partir de leurs habitudes de tenir, de bouger et de déplacer leurs téléphones. Dans ce contexte, les données sont acquises par des capteurs inertiels embraqués dans les appareils mobiles
The research goal of this work is to develop learning methods advancing automatic analysis and interpreting of human motion from different perspectives and based on various sources of information, such as images, video, depth, mocap data, audio and inertial sensors. For this purpose, we propose a several deep neural models and associated training algorithms for supervised classification and semi-supervised feature learning, as well as modelling of temporal dependencies, and show their efficiency on a set of fundamental tasks, including detection, classification, parameter estimation and user verification. First, we present a method for human action and gesture spotting and classification based on multi-scale and multi-modal deep learning from visual signals (such as video, depth and mocap data). Key to our technique is a training strategy which exploits, first, careful initialization of individual modalities and, second, gradual fusion involving random dropping of separate channels (dubbed ModDrop) for learning cross-modality correlations while preserving uniqueness of each modality-specific representation. Moving forward, from 1 to N mapping to continuous evaluation of gesture parameters, we address the problem of hand pose estimation and present a new method for regression on depth images, based on semi-supervised learning using convolutional deep neural networks, where raw depth data is fused with an intermediate representation in the form of a segmentation of the hand into parts. In separate but related work, we explore convolutional temporal models for human authentication based on their motion patterns. In this project, the data is captured by inertial sensors (such as accelerometers and gyroscopes) built in mobile devices. We propose an optimized shift-invariant dense convolutional mechanism and incorporate the discriminatively-trained dynamic features in a probabilistic generative framework taking into account temporal characteristics. Our results demonstrate, that human kinematics convey important information about user identity and can serve as a valuable component of multi-modal authentication systems

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Santos, Michele Caroline dos. "Análise eletromiográfica da sobrecarga postural causada pelo colete balístico em profissionais de segurança pública." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/2040.

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As situações de trabalho que o policial militar está exposto exigem padrões posturais que sobrecarregam as estruturas músculos-esqueléticas podendo desencadear dores na coluna lombar. Na atividade policial militar os indivíduos que desempenham a atividade operacional permanecem 12 horas seguidas utilizando equipamentos obrigatórios de segurança, equipamentos esses que podem totalizar 5,7 kg, essa singularidade da função aliadas a posição sentada na viatura podem levar a sobrecarga da coluna vertebral. O objetivo desse trabalho foi verificar a resposta eletromiográfica em policiais militares operacionais antes e após jornada de trabalho. Foram avaliados 44 indivíduos, do sexo masculino, com uma média de idade de 34,59±8,05 anos. O protocolo utilizado consistiu na avaliação dos músculos paravertebrais e reto abdominal em um teste de contração máxima (CIVM) no movimento de extensão de tronco, partindo da posição sentada. E ainda, foram utilizados o questionário de avaliação funcional Roland-Morris e o diagrama de áreas dolorosas de Corlett e Manenica. Utilizou-se um eletromiógrafo de 16 canais, previamente configurados. O sinais foram processados no domínio temporal (EMGME) e espectral (EMGFM), utilizando o programa MatLab®. Aplicaram-se testes estatísticos de Shapiro-Wilk e Wilcoxon Signed Ranks Test. As análises estatísticas foram realizadas através do software SPSS v21.0 e Microsoft Office Excel 2010 considerando como nível de significância p<0,05. Os resultados mostraram diferenças estatísticas no pós-turno de trabalho na análise temporal, um decréscimo na EMGME no músculo reto abdominal direito (p= 0,016) e na amostra estratificada por idade, com sujeitos acima de 31 anos de idade, (p= 0,016),na análise espectral, redução na EMGFM no músculo Iliocostal direito (p= 0,027) e lados direito e esquerdo na amostra estratificada, em sujeito com mais de 31 anos de idade e com mais de 10 anos de serviço, 50% dos avaliados assinalaram o nível 4 do diagrama de áreas dolorosas e no questionário Roland-Morris, foram encontradas diferenças significativas nos sujeitos com mais de 10 anos de serviço. O protocolo utilizado evidenciou uma diminuição da amplitude do sinal eletromiográfico bem como uma possível fadiga muscular do lado onde usualmente os policiais utilizam seu armamento no pós-turno de trabalho de policiais militares operacionais bem como desconforto postural na região toracolombar e alteração de funcionalidade da coluna devido à queixa álgica na amostra estudada.
The working situations that a military police officer is exposed demand postural patterns that overload the muscle-skeletal structures leading to lower back pain. During the military police activity the individuals who take part in the operational activity spend 12 hours in a row wearing mandatory safety equipment, that can weight up to 5.7 kg, this function singularity along with sitting position inside the patrol car may lead to an overload on the spine. The objective of this work was to verify the neuromuscular response through electromyography in operational military police officers before and after the working shifts. 44 male subjects have been evaluated, with an average of 34.59±8.05 years of age. The protocol used consisted in the evaluation of the paravertebral muscles and abdominal rectus in a maximum contraction test (CIVM) in the extension movement of the upper body. And yet, the Roland-Morris’ functional evaluation questionnaire and the Corlett and Manenica’s painful areas diagram were used. A previously set 16-channel electromyograph has been used. The signal were processed in the temporal (midline of energy) and spectral domain (midline of frequency), using the computer software MatLab®. Shapiro-Wilk statistical tests and Wilcoxon Signed Ranks Test were applied the analysis were carried out through the software SPSS v21.0 and Microsoft Office Excel 2010 considering as significance level p<0.05. The results showed differences in statistics after work in temporal analysis, a decrease in EMGME in the rectus abdominis muscle (p = 0.016) and in the sample stratified by age, with subject over 31 years of age, (p = 0.016), spectral analysis, reduction in EMGFM in the iliocostalis right (p = 0.027) and right and left sides in stratified sampling, in subject with more than 31 years of age and with more than 10 years of service , 50% of the assessed level 4 noted the painful areas and diagram on the Roland-Morris questionnaire, significant differences were found in subjects with more than 10 years of service. The protocol used showed a decrease in the amplitude of the electromyographic signal as well as a possible muscle fatigue on the side where the cops usuallytheir guns after the military police work well as postural discomfort on thoracolumbar region and change the functionality of the column due to complaint algic in the sample studied.

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Bell, Alison. "An ergonomic analysis of vacuum cleaning tasks using observational risk assessment tools." School of Health Sciences - Faculty of Health & Behavioural Sciences, 2008. http://ro.uow.edu.au/theses/126.

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This research thesis examined the risk of upper limb musculoskeletal disorders for cleaning workers while performing vacuum cleaning tasks in the normal course of their employment. The cleaning workers in this study were from three sectors of the workforce – government schools, hospitality and commercial office space. The vacuum cleaning tasks were divided into those performed with a back pack style vacuum cleaning machine and those using a canister/barrel machine. Three observational risk assessment tools were selected to measure the risk of these tasks to cleaning workers. The selected tools were the Manual Tasks Risk Assessment Tool (ManTRA) version 2.0; the Quick Exposure Check (QEC) (Li & Buckle, 1998); and the Rapid Upper Limb Assessment tool (RULA) (McAtamney & Corlett, 1993). Results of this thesis study demonstrated that vacuum cleaning is a risk to the musculoskeletal health of cleaning workers, with some variation between the tool ratings, reflecting the specificity and/or sensitivity of each tool. Differences were found between the three cleaning sectors in terms of overall risk posed by vacuum cleaning tasks. The sector with the greatest risk was found to be the government school cleaners, followed by the hospitality and then commercial office space cleaning sectors. The ‘risk experience’ difference between the sectors cannot be attributed only to vacuum cleaner characteristics, but also, the environment and length of shift worked by the cleaning staff. Further research is required to determine the difference in risk exposure between the two types of vacuum cleaner (back pack and canister).

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Van, der Westhuizen Gareth. "Design, implementation & analysis of a low-cost, portable, medical measurement system through computer vision." Thesis, Stellenbosch : University of Stellenbosch, 2011. http://hdl.handle.net/10019.1/6764.

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Thesis (MScEng (Mechanical and Mechatronic Engineering))--University of Stellenbosch, 2011.
ENGLISH ABSTRACT: The In the Physiotherapy Division of the Faculty of Health Sciences on the Tygerberg Hospital Campus of the University of Stellenbosch, the challenge arose to develop a portable, affordable and yet accurate 3D measurement machine for the assessment of posture in school children in their classroom environment. Currently Division already uses a state-of-the-art VICON commercial medical measuring machine to measure human posture in 3D in their physiotherapy clinic, but the system is not portable and is too expensive to cart around to different places for testing. To respond to this challenge, this Master’s thesis designed and analyzed a machine and its supporting system through both research on stereo-vision methodologies and empirical appraisal in the field. In the development process, the research was required to overcome the limitations posed by small image resolutions and lens distortions that are typical of cheap cameras. The academic challenge lay in the development of an error prediction model through Jacobian derivation and Error Propagation Law, to predict uncertainties of angular measurement calculated by the system. The research culminated in a system that is comparable in accuracy to the VICON within 3mm, and that has 1.5mm absolute accuracy within its own system for a measurement volume radius of 2.5 m. As such, the developed error model is an exact predictor of the angular error to within 0.02° of arc. These results, for both system accuracy and the error model, exceed the expectations on the basis of the initial challenge of the system. The development of the machine was successful in providing a prototype tool that is suitable for commercial development for use by physiotherapists in human posture measurement and assessment. In its current incarnation, the machine will also serve the Engineering Faculty as the most fundamental form of a three-dimensional measuring apparatus using only basic theories and algorithms of stereo-vision, thereby providing a basic experimental platform from which further scientific research on the theory and application of computer vision can be conducted.
AFRIKAANSE OPSOMMING: Die Fisioterapie Afdeling van die Fakulteit Gesondheidswetenskappe op die Tygerberg kampus van die Universiteit van Stellenbosch gebruik ’n allernuutste VICON kommersiële mediese meettoestel om menslike postuur in drie dimensies te meet. Vanuit hierdie Afdeling het die uitdaging ontstaan om ’n draagbare, bekostigbare, maar tog akkurate, drie-dimensionele meetapparaat geskik vir die meet van die postuur van skoolkinders in die klaskamer te ontwikkel. In aanvaarding van hierdie uitdaging, het hierdie Magistertesis ’n toestel en ondersteuningstels ontwerp en ontleed deur beide navorsing in stereo-visie metodiek en terplaatse beoordeling. In die ontwikkelingsproses moes die navorsing die beperkings wat deur klein-beeld resolusie en lens-distorsie (tipies van goedkoop kameras) meegebring word, oorkom. Die akademiese uitdaging lê in die ontwikkeling van ’n voorspellende foutmodel deur van die Jacobianse-afleiding en die Fout Propageringswet gebruik te maak om onsekerheid van hoeksberekening deur die stelsel te voorspel. Die navorsing het gelei tot ’n stelsel wat binne 3mm vergelykbaar is in akkuraatheid met dié van die VICON en ook 1.5mm absolute interne akkuraatheid het in ’n meet-volume radius van 2.5m radius. Die ontwikkelde foutmodel is dus ’n presiese voorspeller van hoekfout tot binne 0.02° van boog. Die resultate met betrekking tot beide die akkuraatheid en die foutmodel het die oorspronklike verwagtinge van die uitdaging oortref. Die ontwikkeling was suksesvol in die skep van ’n prototipe-toestel geskik vir kommersiële ontwikkeling, vir gebruik deur fisioterapeute in die meting en evaluering van menslike postuur. Die stelsel is in sy fundamentele vorm, deur die gebruik van slegs basiese teorieë en algoritmes van stereo-visie, funksioneer as ’n drie-dimensionele meetapparaat. In die fundamentele vorm sal die stelsel die Ingenieursfakulteit dien as ’n basiese eksperimentele platform waarop verdere wetenskaplike navorsing in die teorie en toepassing van rekenaar-visie gedoen kan word.

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Desombre, Laurent. "Fiabilité et modélisation cognitive de l'opérateur humain face à des signaux visuo-posturaux." Valenciennes, 1997. https://ged.uphf.fr/nuxeo/site/esupversions/a9fc578f-b8df-4eab-b503-cedffac16912.

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Le travail présenté dans ce mémoire entre dans le cadre d'un contrat de recherche établi entre la direction de la recherche et de la technologie (division ergonomie - ministère de la défense) et le laboratoire d'automatique et de mécanique industrielles et humaines. L'évolution des systèmes vers une automatisation de plus en plus poussée conduit très souvent à transformer l'activité humaine dans les moyens de transport par air, mer ou terre, en une activité de surveillance et de contrôle d'interface graphique assurant les interactions homme-machine. La monotonie de la tâche qui en résulte associée aux contraintes caractérisant les conditions de travail, ont des effets négatifs sur la vigilance et la performance des opérateurs humains et plus généralement sur la sécurité des systèmes. Aussi convient-il d'analyser les caractéristiques de la situation de travail et de l'operateur pour répondre à un besoin double d'analyse fiabiliste et de modélisation du comportement humain en régime perturbé ou face à une situation accidentelle. Les travaux résumés dans ce mémoire visent à poursuivre l'exploration des perturbations temporaires affectant le fonctionnement des opérateurs, perturbations liées ici aux contraintes temporelle, visuelle et posturale de la situation de travail. Ils englobent à la fois des travaux sur les stimulations vestibulaires d'origine vibratoire et des études sur la présentation d'informations visuelles sur écran graphique, et sont abordés dans une perspective pluridisciplinaire, conciliant aspects humains et automatiques. La situation analysée est celle d'un opérateur humain effectuant une tache de catégorisation de signaux visuels, de durée limitée et de nature simple et répétitive ; sa complexité réside dans la part de réflexion nécessaire à la discrimination de ces messages en fonction de critères définis à l'avance. Au point de vue méthodologie, les données sont traitées dans le cadre de la théorie de la détection du signal dont la principale originalité est d'isoler dans l'acte perceptif, le processus décisionnel du processus sensoriel. Dans ce cadre théorique, trois expérimentations ont été réalisées. La mise en place d'un dispositif d'évaluation des performances perceptives et cognitives de l'opérateur humain effectuant une prise de décision, a fait l'objet de la première expérimentation. Au cours de la deuxième expérimentation, la charge de travail et la capacité perceptive et cognitive de l'opérateur humain sont analysées dans l'environnement vibratoire d'un voilier dans diverses conditions de navigation rencontrées au cours de l'expédition de celui-ci dans l'antarctique. Les taches visuo-cognitivo-motrices de l'opérateur humain pendant ces deux séries d'expériences ont été réalisées avec un temps imposé fixe qui est modulé dans la troisième expérimentation. Dans celle-ci et dernière expérimentation, le rôle et les effets des modifications de la pression temporelle, des faibles variations d'amplitude des stimuli graphiques et des stimulations vestibulaires d'origine vibratoire, sont examinés sur les performances de l'opérateur humain effectuant une tache de détection de variation de figures graphiques. L'analyse des données recueillies tout au long de la phase expérimentale, fait appel dans une première approche à une méthodologie d'évaluation basée sur un modèle statistique, dont la structure est l'analyse Bayesienne des comparaisons. Ce choix est directement suggéré par la mesure de l'activité de l'homme. L'autre approche est plus globale car elle permet de tenir compte du caractère multivariable du comportement humain. La technique d'analyse de données est alors multidimensionnelle : analyse en composantes principales. Finalement, une tentative de modélisation des phénomènes observés dans l'environnement visuo-postural étudié et une identification des lois expérimentales obtenues permettent d'interpréter les résultats et de les présenter sous la forme de modèles. La mise en œuvre de ces modèles fait l'objet de la dernière partie de ce mémoire. L'originalité réside alors dans l'analyse des raisonnements, représentations mentales et mécanismes automatiques liés aux diverses prises de décisions affectées par un jeu de contraintes (délai, difficulté d'observation, stimulations vestibulaires) s'exerçant sur l'opérateur humain.

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Morphett, Adrian. "Workplace analysis for regional pain syndrome the development and application of posture measurement model and cervical assessement tools for reducing the risk of regional pain syndrome /." Swinburne Research Bank, 2009. http://hdl.handle.net/1959.3/67282.

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Thesis (PhD) - Swinburne University of Technology, Faculty of Engineering and Industrial Sciences, 2009.
A thesis submitted for the degree of Doctor of Philosophy, Faculty of Engineering and Industrial Sciences, Swinburne University of Technology, 2009. Typescript. "February 2009". Includes bibliographical references (p. 291-313)

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Youbi, Abdelaziz. "Méthode d'analyse des réponses cardio-vasculaire de sujets à des changements posturaux et d'activité." Paris 6, 1988. http://www.theses.fr/1988PA066607.

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Baradel, Fabien. "Structured deep learning for video analysis." Thesis, Lyon, 2020. http://www.theses.fr/2020LYSEI045.

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Avec l’augmentation massive du contenu vidéo sur Internet et au-delà, la compréhension automatique du contenu visuel pourrait avoir un impact sur de nombreux domaines d’application différents tels que la robotique, la santé, la recherche de contenu ou le filtrage. Le but de cette thèse est de fournir des contributions méthodologiques en vision par ordinateur et apprentissage statistique pour la compréhension automatique du contenu des vidéos. Nous mettons l’accent sur les problèmes de la reconnaissance de l’action humaine à grain fin et du raisonnement visuel à partir des interactions entre objets. Dans la première partie de ce manuscrit, nous abordons le problème de la reconnaissance fine de l’action humaine. Nous introduisons deux différents mécanismes d’attention, entrainés sur le contenu visuel à partir de la pose humaine articulée. Une première méthode est capable de porter automatiquement l’attention sur des points pré-sélectionnés importants de la vidéo, conditionnés sur des caractéristiques apprises extraites de la pose humaine articulée. Nous montrons qu’un tel mécanisme améliore les performances sur la tâche finale et fournit un bon moyen de visualiser les parties les plus discriminantes du contenu visuel. Une deuxième méthode va au-delà de la reconnaissance de l’action humaine basée sur la pose. Nous développons une méthode capable d’identifier automatiquement un nuage de points caractéristiques non structurés pour une vidéo à l’aide d’informations contextuelles. De plus, nous introduisons un système distribué entrainé pour agréger les caractéristiques de manière récurrente et prendre des décisions de manière distribuée. Nous démontrons que nous pouvons obtenir de meilleures performances que celles illustrées précédemment, sans utiliser d’informations de pose articulée au moment de l’inférence. Dans la deuxième partie de cette thèse, nous étudions les représentations vidéo d’un point de vue objet. Étant donné un ensemble de personnes et d’objets détectés dans la scène, nous développons une méthode qui a appris à déduire les interactions importantes des objets à travers l’espace et le temps en utilisant uniquement l’annotation au niveau vidéo. Cela permet d’identifier une interaction inter-objet importante pour une action donnée ainsi que le biais potentiel d’un ensemble de données. Enfin, dans une troisième partie, nous allons au-delà de la tâche de classification et d’apprentissage supervisé à partir de contenus visuels, en abordant la causalité à travers les interactions, et en particulier le problème de l’apprentissage contrefactuel. Nous introduisons une nouvelle base de données, à savoir CoPhy, où, après avoir regardé une vidéo, la tâche consiste à prédire le résultat après avoir modifié la phase initiale de la vidéo. Nous développons une méthode basée sur des interactions au niveau des objets capables d’inférer les propriétés des objets sans supervision ainsi que les emplacements futurs des objets après l’intervention
With the massive increase of video content on Internet and beyond, the automatic understanding of visual content could impact many different application fields such as robotics, health care, content search or filtering. The goal of this thesis is to provide methodological contributions in Computer Vision and Machine Learning for automatic content understanding from videos. We emphasis on problems, namely fine-grained human action recognition and visual reasoning from object-level interactions. In the first part of this manuscript, we tackle the problem of fine-grained human action recognition. We introduce two different trained attention mechanisms on the visual content from articulated human pose. The first method is able to automatically draw attention to important pre-selected points of the video conditioned on learned features extracted from the articulated human pose. We show that such mechanism improves performance on the final task and provides a good way to visualize the most discriminative parts of the visual content. The second method goes beyond pose-based human action recognition. We develop a method able to automatically identify unstructured feature clouds of interest in the video using contextual information. Furthermore, we introduce a learned distributed system for aggregating the features in a recurrent manner and taking decisions in a distributed way. We demonstrate that we can achieve a better performance than obtained previously, without using articulated pose information at test time. In the second part of this thesis, we investigate video representations from an object-level perspective. Given a set of detected persons and objects in the scene, we develop a method which learns to infer the important object interactions through space and time using the video-level annotation only. That allows to identify important objects and object interactions for a given action, as well as potential dataset bias. Finally, in a third part, we go beyond the task of classification and supervised learning from visual content by tackling causality in interactions, in particular the problem of counterfactual learning. We introduce a new benchmark, namely CoPhy, where, after watching a video, the task is to predict the outcome after modifying the initial stage of the video. We develop a method based on object- level interactions able to infer object properties without supervision as well as future object locations after the intervention

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Li, Ching-Lung, and 李青龍. "Analysis and Control Design for Emulated Human Postural Balancing Systems." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/51284726160394539638.

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碩士
國立中興大學
電機工程學系所
95
The aim of this thesis is to characterize a mathematical model, including canal-otolith interaction, to describe biological interaction of the human upright standing posture and biological characteristics. The model explains and describes the subjective vertical orientation, angular velocity induced static tilt, and how does this phenomenon to affect the human upright standing postural balance. On the basis of the model, a state feedback control law is presented to assist the balance of the human’s standing posture that is interfered by the subjective verticals with the phenomenon of subjective vertical orientation illusion treated as an external disturbance. A robust control law is developed to guarantee the posture stability while there is plant uncertainties caused by the effect of vertigo. It is expected that this research could be served as a preliminary for designing postural control law for the future humanoid robots.

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27

Sousa, Andreia Sofia Pinheiro de. "Biomechanical Analysis of Human Movement and Postural Control based on Multifactorial Correlation and Clinical Implications." Doctoral thesis, 2013. https://repositorio-aberto.up.pt/handle/10216/86266.

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28

Sousa, Andreia Sofia Pinheiro de. "Biomechanical Analysis of Human Movement and Postural Control based on Multifactorial Correlation and Clinical Implications." Tese, 2013. https://repositorio-aberto.up.pt/handle/10216/86266.

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29

Pelliccia, Luigi. "HuPOSE: Human-like posture generation and biomechanical analysis for human figures." Tesi di dottorato, 2013. http://www.fedoa.unina.it/9549/1/pelliccia_luigi_25.pdf.

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Over the years an increasing attention has been devoted to ergonomic analyses even from the early stage of the design process. Ergonomic and human factor evaluations often require building a physical mock-up in order to provide an assessment of discomfort and ease of use. This process, using traditional methods, is very time demanding, especially when the design has to be modified and revalidated. Digital mock-up instead, enables manu- facturers to design digital prototypes of a product in full details, simulating its functions and predicting interaction among its different components. In order to take advantage of digital simulation to conduct ergonomic assessments digital substitutes of human beings (also called digital humans), able to interact with the digital mock-up in simulation environment, are required. Since these digital humans are required to simulate human beings in digital environments their resulting movements must be as human-like as possible. Although these digital human simulation tools are now advanced enough to correctly predict human-product and human-process interaction, even before a physical prototype is constructed, the animation process is still very time demanding, mainly because it still relies on key frame techniques. Moreover, the accuracy of the resulting simulations are strongly related to the experience of the operator. The aim of this thesis has been to develop an algorithm capable of speeding up the animation process of digital humans. An algorithm capable of conducting biomechanical analyses has been developed as well. Chapter 1 provides a general introduction underlining the need to use digital human simulation tools from the early stage of the design process. The main applications of digital technologies in industrial world are presented as well. Chapter 2 provides an overview of the the main digital human simulation tools currently available, highlighting their advantages and disadvantages. Chapter 3 describes the mathematical theory underlying the developed HuPOSE model. Both the kinematic and the biomechanical model are presented. The main contribution is the formulation of the inverse kinematic problem in terms of a single CLIK algorithm, using an Augmented Jacobian matrix. This approach suggested also the possibility of computing the static torques at the joints of a digital human by means of kineto-static duality. The computation of the static torques allowed to conduct a biomechanical analysis, in reference to a load-lifting task, very easily. Chapter 4 discusses several possible application for the developed HuPOSE model. Simulation in virtual environment have been conducted using Matlab–Simulink in order to show the ease of motion planning for a human figure. The implemented whole-body motion control technique takes into account the position of the centre of pressure of the digital human. This technique allows to achieve quite natural movements in spite of the limited number of task related control points considered. A biomechanical analisys is presented as well, whose results are results are in good agreement with literature data. Chapter 5 contains the main results achieved, remarks and proposals for future development

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30

Yang, Tai-Chang, and 楊岱璋. "A Real-Time Human Motion Tracking and Posture Analysis." Thesis, 2002. http://ndltd.ncl.edu.tw/handle/76022824615076178318.

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碩士
國立清華大學
電機工程學系
90
In this thesis, we introduce a real time people tracking detection and posture analysis under frequency domain and use a principal component analysis (PCA) model to generate an eigenspace. In general, the shape and silhouette of 2-D projection of human postures is changeless and it is a cue for us to determine what the person is doing. The postures we want to classify are stand, sit, bend, raise-hand, lying and walking. For these postures, we want to recognize each of them in spite of tiny variance of contour. In the whole system, in order to obtain a more clear and complete foreground silhouette, a method of background of maintenance and preprocessing of filtering noise is included. In the beginning of our system, there is a method of background subtraction and preprocessing, which include labeling of connected components, shape remover, morphology opening and closing. Then trace the contour pixels with a start point and sort them in order. With the ordered contour pixels, we can apply Fourier Descriptor (F.D.) on them to analysis the frequency component of our defined posture. And then estimate the similarity between F.D. of current image and the pre-stored data by our PCA models. With finding the maximum similarity, we can classify what the posture now is belonging to. The PCA model is used to generate an eigenspace by training each of the same posture of different people. And then we can recognize each posture according to these trained data. Under the condition and ability the hardware could provide, our system will analyze each frame of video input within about 1/15 second and achieve a near-real-time system.

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31

Wu, Jiuh-Rou, and 吳聚柔. "Automatic Human Body Extraction and Posture Analysis in Consecutive Images." Thesis, 2007. http://ndltd.ncl.edu.tw/handle/81066389184168081432.

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碩士
國立中興大學
電機工程學系所
95
In this thesis, two kinds of human body posture analysis methods are proposed. One is continuous human body posture recognition by a recurrent fuzzy neural network, and the other is human posture estimation by silhouette and skin color information. Before posture analysis, it is necessary to segment the human body from background. A moving object segmentation algorithm is proposed to distinguish the human body from background from a sequence of images. This algorithm uses an automatic threshold determination method with Euler numbers for frame and background differences. After segmentation, a series of image processing is used obtain a complete silhouette of human body. The objective of posture recognition is to recognize four types of main body postures, including standing, bending, sitting, and lying. The significant Discrete Fourier Transform (DFT) coefficients of horizontal and vertical histograms together with length-width ratio of the silhouette are used as features. Recognizer is designed by a recurrent neural fuzzy network. In posture estimation, our objective is to locate significant body points. We combined skin color information with the convex points of contour of human body to locate head, hands, and feet. Experiment results show that the proposed approach can recognize the four types of postures and locate the significant points of human body with good performance.

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32

Reddi, Sarath. "A Geometric Approach for Discrete and Statistical Reach Analysis for a DHM with Mutable Supports." Thesis, 2013. http://etd.iisc.ac.in/handle/2005/2867.

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Abstract:

Conventional ergonomics analysis involves building physical mockups and conducting simulated operations, such that the constraints experienced by the human subjects can be directly observed. The limitations of this approach are that, they are resource intensive, less ﬂexible for testing design variability and diﬃcult to involve large number of subjects to account for population variability and thus, it is a reactive approach. With the advent of computer aided techniques, eﬀorts are on to support ergonomics analysis processes for proactive design approaches. To achieve this, real scenarios are being simulated in virtual environments which include induction of representative human subjects into such envi-ronments and are termed as Digital Human Models (DHMs). The main challenge in the simulation of humans is to obtain the naturalness that is perceived in human interaction with the environment. This naturalness can be achieved by synergetically modeling the physical performance and cognitive aspects of humans in such a way that one aspect caters the requirements posed from the other. But in current DHMs, the various elements in the physical performance aspect are not in line with the requirements of higher level behav¬ioral/cogntive aspects. Towards meeting this objective, the inﬂuence of physical performance aspects of humans on achieving naturalness when DHM interacts with the virtual environment has been studied. In this work, the task of ’reach’ has been chosen for studying the inﬂuence of kinematic structure, posture modeling and stability aspects on achieving naturalness for both discrete and statistical humans. Also, a framework has been developed to give instructions based on relations between the segments of the body and objects in the environment. Kinematic structure is modeled to simulate the humans with varied dimensions taking care of the change of link ﬁxations necessary for various tasks. The conventional techniques used to deﬁne kinematic structures have limitations in resolving the issues that arise due to change in link ﬁxations. In this work a new scheme is developed to eﬀectively handle precedence relationship sand change of conﬁguration of the existing posture whenever link ﬁxations change. The advantage with this new approach is that complex maneuvers which involve diﬀerent link ﬁxations and multiple ﬁxations at a time can be managed automati¬cally without the user’s intervention. Posture prediction involves estimation of the whole body posture which a human operator is likely to assume while performing a task. It involves ﬁnding a conﬁguration satisfy¬ing the constraints like placing the body-segments in preferred locations of the task space and satisfying the relations speciﬁed between body segments. There are two main chal¬lenges in this regard; one is achieving naturalness in the predicted postures and the other is minimizing the mathematical complexity involved in ﬁnding the real time solutions. A human-speciﬁc posture prediction framework is developed which can handle a variety of constraints and realize the natural behavior. The approach is completely geometry based and unlike numerical methods, the solutions involve no matrix inversions. Digital human models (DHMs), both as avatars and agents, need to be controlled to make them manipulate the objects in the virtual world. A relations based description scheme is developed to instruct the DHM to perform the tasks. The descriptions as a set of relations and postures involve simple triplets and quadruplets. As the descriptions constitute only the relations between actors, incorporating diﬀerent behavior models while executing the relations is feasible through this framework. Static balancing is one of the crucial factors inﬂuencing the posture of humans. The stim¬ulus for the static balancing is the body’s self weight and is governed by the location of its point of application, namely the center of mass (COM). The main focus is on determin¬ing suitable locations for COM to infer about the mobility of the segments which supports the human structure in slow motion scenarios. Various geometric conditions necessary for support retaining, altering are deduced and developed strategies for posture transitions for eﬀective task performance while maintaining stability. These conditions are useful in de¬termining the posture transition required to shift the COM from one region to the other and thus the behaviors realized while accomplishing the tasks are realistic. These behaviors are simulated through statically stable walking and sit to stand posture transition. One of the advantages of employing DHMs in virtual simulations is the feasibility of creat¬ing human models with varied dimensions. A comparative study is conducted on diﬀerent methods based on probabilistic and statistic theory as an alternative to the percentile based approach with a view to answer the questions like ’what percentage of people can success-fully accomplish a certain task’ and ’how well can people perform when they reach a point in the operational space’. The case study is done assuming upper and lower arms of hu¬mans as a two link planar manipulator and their link lengths as random variables. Making use of statistical DHMs, the concept of task dependent boundary manikins is introduced to geometrically characterize the extreme individuals in the given population who would ac-complish the task. Simulations with these manikins would help designers to visualize how differently the extreme individuals would perform the task. All these different aspects of DHM discussed are incorporated in our native DHM developed named ’MAYAMANAV’. Finally this thesis will end with conclusions and future work discussing how these diﬀerent aspects of DHM discussed can be combined with behavioral models to simulate the human error.

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33

Reddi, Sarath. "A Geometric Approach for Discrete and Statistical Reach Analysis for a DHM with Mutable Supports." Thesis, 2013. http://etd.iisc.ernet.in/handle/2005/2867.

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Abstract:

Conventional ergonomics analysis involves building physical mockups and conducting simulated operations, such that the constraints experienced by the human subjects can be directly observed. The limitations of this approach are that, they are resource intensive, less ﬂexible for testing design variability and diﬃcult to involve large number of subjects to account for population variability and thus, it is a reactive approach. With the advent of computer aided techniques, eﬀorts are on to support ergonomics analysis processes for proactive design approaches. To achieve this, real scenarios are being simulated in virtual environments which include induction of representative human subjects into such envi-ronments and are termed as Digital Human Models (DHMs). The main challenge in the simulation of humans is to obtain the naturalness that is perceived in human interaction with the environment. This naturalness can be achieved by synergetically modeling the physical performance and cognitive aspects of humans in such a way that one aspect caters the requirements posed from the other. But in current DHMs, the various elements in the physical performance aspect are not in line with the requirements of higher level behav¬ioral/cogntive aspects. Towards meeting this objective, the inﬂuence of physical performance aspects of humans on achieving naturalness when DHM interacts with the virtual environment has been studied. In this work, the task of ’reach’ has been chosen for studying the inﬂuence of kinematic structure, posture modeling and stability aspects on achieving naturalness for both discrete and statistical humans. Also, a framework has been developed to give instructions based on relations between the segments of the body and objects in the environment. Kinematic structure is modeled to simulate the humans with varied dimensions taking care of the change of link ﬁxations necessary for various tasks. The conventional techniques used to deﬁne kinematic structures have limitations in resolving the issues that arise due to change in link ﬁxations. In this work a new scheme is developed to eﬀectively handle precedence relationship sand change of conﬁguration of the existing posture whenever link ﬁxations change. The advantage with this new approach is that complex maneuvers which involve diﬀerent link ﬁxations and multiple ﬁxations at a time can be managed automati¬cally without the user’s intervention. Posture prediction involves estimation of the whole body posture which a human operator is likely to assume while performing a task. It involves ﬁnding a conﬁguration satisfy¬ing the constraints like placing the body-segments in preferred locations of the task space and satisfying the relations speciﬁed between body segments. There are two main chal¬lenges in this regard; one is achieving naturalness in the predicted postures and the other is minimizing the mathematical complexity involved in ﬁnding the real time solutions. A human-speciﬁc posture prediction framework is developed which can handle a variety of constraints and realize the natural behavior. The approach is completely geometry based and unlike numerical methods, the solutions involve no matrix inversions. Digital human models (DHMs), both as avatars and agents, need to be controlled to make them manipulate the objects in the virtual world. A relations based description scheme is developed to instruct the DHM to perform the tasks. The descriptions as a set of relations and postures involve simple triplets and quadruplets. As the descriptions constitute only the relations between actors, incorporating diﬀerent behavior models while executing the relations is feasible through this framework. Static balancing is one of the crucial factors inﬂuencing the posture of humans. The stim¬ulus for the static balancing is the body’s self weight and is governed by the location of its point of application, namely the center of mass (COM). The main focus is on determin¬ing suitable locations for COM to infer about the mobility of the segments which supports the human structure in slow motion scenarios. Various geometric conditions necessary for support retaining, altering are deduced and developed strategies for posture transitions for eﬀective task performance while maintaining stability. These conditions are useful in de¬termining the posture transition required to shift the COM from one region to the other and thus the behaviors realized while accomplishing the tasks are realistic. These behaviors are simulated through statically stable walking and sit to stand posture transition. One of the advantages of employing DHMs in virtual simulations is the feasibility of creat¬ing human models with varied dimensions. A comparative study is conducted on diﬀerent methods based on probabilistic and statistic theory as an alternative to the percentile based approach with a view to answer the questions like ’what percentage of people can success-fully accomplish a certain task’ and ’how well can people perform when they reach a point in the operational space’. The case study is done assuming upper and lower arms of hu¬mans as a two link planar manipulator and their link lengths as random variables. Making use of statistical DHMs, the concept of task dependent boundary manikins is introduced to geometrically characterize the extreme individuals in the given population who would ac-complish the task. Simulations with these manikins would help designers to visualize how differently the extreme individuals would perform the task. All these different aspects of DHM discussed are incorporated in our native DHM developed named ’MAYAMANAV’. Finally this thesis will end with conclusions and future work discussing how these diﬀerent aspects of DHM discussed can be combined with behavioral models to simulate the human error.

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34

Granata-Clark, Kim. "Ergonomic analysis of posture among members of a landscape tree crew /." 2005. http://proquest.umi.com/pqdweb?did=1034613561&sid=1&Fmt=6&clientId=17867&RQT=309&VName=PQD.

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Thesis (M.S.)--San Jose State University, 2005.
Includes abstract. Includes bibliographical references (leaves 71-73). Subscription required for access to full text. ProQuest ; Also available via the World Wide Web ;

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35

Huang, Pei-Chung, and 黃培忠. "A Behavior Analysis System Using Human Silhouette Features and Static Posture Classification." Thesis, 2008. http://ndltd.ncl.edu.tw/handle/02170160128046564070.

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碩士
中原大學
資訊工程研究所
96
With the advance of technology, the surveillance system has been widely used in many environments. Computer vision and multimedia techniques make feasible the development of new and “smart” surveillance systems that are different from traditional systems with only the recording function. In recent research, the surveillance system has been designed to automatically detect the location of human in video and to analyze the human behavior. In this paper, the objective is to identify and track the location of human, to match various static posture states in human behavior with respect to an established database, and to recognize the actual human behavior. The system design includes pre-processing of objects, object normalization, feature extraction of human, and collection of a database of human behavior for further analysis. The system was developed using 20 standard behavior as training samples, and was then evaluated with 32 unknown behavior samples. In addition, 2322 and 610 static poses were also evaluated. Our preliminary results demonstrated a 90% of classification in recognizing the two human behavior, namely the “walking” or “running”. In conclusion, human behavior is composed of many static posture states. Our methods could be used to analyze the combination of these states, and ultimately applied in surveillance systems with the need to recognize various humanbehavior.

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36

Chen, Jiun-Liang, and 陳俊良. "A Principal-Component-Analysis-Based Approach to Recognizing the Postures of Human Silhouettes." Thesis, 2003. http://ndltd.ncl.edu.tw/handle/55524967456016448274.

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Abstract:

碩士
國立臺灣科技大學
自動化及控制研究所
91
In this thesis, we present a principal component analysis (PCA) method to recognize body postures in real-time, which produces an eigenspace as our recognition model since a body posture in a two-dimensional image generally has a fixed shape and silhouette. Many different postures mainly made by various hands’ swing are used for identification. To get more complete foreground, the finding of a threshold for separating foreground from background followed by a noise removal process are first performed in our recognition system. At the beginning, this system adopts a background subtraction method to obtain foreground which is further preprocessed. Background subtraction is the method that the current image is cut off to get a rough foreground by means of finding an appropriate threshold to binarize the image so as to figure out foreground and background. Subsequently, both opening and closing operations in mathematical morphology are employed to erase noises. After this, connected components are searched for constitating a complete foreground. Next, we determine the contour pixel of foreground, which are sorted in an order and then recorded.. To recognize body postures, we take these ordered data as our main training samples. In experiments, we demonstrate 15 distinct postures and every posture has 10 samples, that is to say, we have 150 training samples. At last, we use the PCA method to find the most important projection vectors, and the corresponding posture can be obtained from solving the smallest vector distance between the input and training images. So far, the experimental results reveal that our approach is efficient and effective to recognize the body postures.

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37

McClymont, Juliet. "An analysis of the relationship between maximum cortical bone thickness and maximum curvature in the metatarsals of Pan and Homo." Thesis, 2013. http://hdl.handle.net/10539/12698.

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Abstract:

A Dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science, November 2012.
Hominoids practice a diverse array of locomotor behavior, from obligate terrestrial bipedalism to arboreal suspensory behavior, which is reflected in the variable morphology found in their foot bones. That hominin foot bones reflect locomotor behavior is also clear, but the forms of locomotor behaviors to be inferred are less clear. Pressure plate studies indicate that the center of pressure tends to move medially in the human foot during the last half of stance phase of bipedal gaits, while it tends to remain relatively more lateral in the bonobo and chimpanzee foot during the last half of stance phase. Here is presented a comparison of metatarsals of Homo sapiens[n=22] and two species of Pan (Pan paniscus [n=15] Pan troglodytes schweinfurthii [n=22]in order to explore the relationship between Homo and Pan metatarsal morphology and foot function. Specifically, this dissertation addresses whether cortical thickness is associated with the position of maximum change in geometry on the plantar surface in metatarsals.

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38

Li, Jui-Cheng, and 李瑞誠. "Vision-based Human Model Construction for Posture Analysis and its Real-time Implementation." Thesis, 2013. http://ndltd.ncl.edu.tw/handle/08954467105217029385.

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碩士
國立中正大學
電機工程研究所
101
In recent years, how to take care for the elderly physical function and quality life has become the focus of public attention. And fall accidents are the most common injuries for the elderly, body imbalance is generally considered the main reason for falling, one study noted that we can observe the usual gesture to estimation probability of falling in the future. so we hope to be able to construct the human body model which contains 11 feature points, recording the current activities of the human body so we can provide the data for the posture analysis , for reaching needs of the elderly, and today such as event detection, behavior analysis, and gesture recognition are very popular issue. In this paper, we propose a vision-based human model construction system for posture analysis, it can operate in most shooting scenarios and users do not need to wear any control sensors, finally the algorithm has been real-time implemented and verified using the TI OMAP4430 application processor (includes dual-core ARM Cortex -A9) embedded platform.

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39

Wang, Che-Jen, and 王哲人. "Analysis and Synthesis of Human Posture by Robust Point Matching and Radial Basis Function Networks." Thesis, 2005. http://ndltd.ncl.edu.tw/handle/70578813125987636156.

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碩士
國立臺灣海洋大學
資訊工程學系
93
In this thesis, a system for analyzing and synthesizing human postures has been proposed. The proposed system first learns a series of sample posture images of a people and extracts some necessary information from this series of images. Then, based on the learned information, the system tries to synthesize new postures of another people similar to the learned postures by using one single posture image of the people. In order to establish the control-point correspondences between the sample posture and the input posture, the proposed system first applies the robust point matching algorithm (RPM) to establish the control-point correspondences between the consecutive sample postures beforehand because the consecutive sample postures are similar and the RPM often works well on this kind of point patterns. Then, the sample posture most similar to the input posture is retrieval by a two-stage procedure. The first stage uses three proposed features to find some sample postures similar to the input posture in a flash. Then, the second stage uses the RPM to perform detailed matching to find the most similar one, and also obtains the control-point correspondences between the input posture and the most similar sample posture. Hence, the control-point correspondences from the input posture to any one of the sample postures can be established via the correspondences among the sample postures. Once the control-point correspondences between the input posture and the sample posture to be synthesized have been established, the radial basis function networks are then applied to synthesize the new posture of the people similar to the sample posture. The proposed system was tested against a subject and experimental results show the feasibility of the proposed approach.

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40

Ho, Ping-Jui, and 何秉叡. "Measurement and Analysis of Human Body''s Balance Ability with Static and Dynamic Standing Postures." Thesis, 2015. http://ndltd.ncl.edu.tw/handle/34717302788140338875.

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碩士
銘傳大學
資訊傳播工程學系碩士班
103
Maintaining the balance of the human body is a remarkable ability for life. The balance ability is not only to reflect the individual condition of body health, but also revealing the body characteristic of the synergistic between the limbs and the muscle. In order to observe the strategies of balance maintaining when the human body in various conditions, the first purpose of this study is to analyze and measure the abilities of static and dynamic standing balances, respectively. The measurement system applies the 3D motion capture device for tracking the 3D motion trajectories of the head, neck, shoulder, hip, knee, ankle, and toe of the human body. The EMG activities of the rectus femoris, biceps femoris, astrocnemius medialis and tibialis anterior are recorded for observing the reaction of the human body. The interactive mechanism is analyzed by the 3D posture of the human body and the EMG activities of the corresponding muscles. Therefore, we can obtain the types of the balance strategy for individuals. The second purpose of this study is to build the national model of the balance ability about the student age from 6 to 12. The model is expected to be applied for the detection of the abnormal balanced development of the student, selection the suitable athletes and examination of the effect about the training plan of the balance ability.

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41

Buckley, John G., Asha Alan R. De, Louise Johnson, and Clive B. Beggs. "Understanding adaptive gait in lower-limb amputees: insights from multivariate analyses." 2013. http://hdl.handle.net/10454/9631.

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In this paper we use multivariate statistical techniques to gain insights into how adaptive gait involving obstacle crossing is regulated in lower-limb amputees compared to able-bodied controls, with the aim of identifying underlying characteristics that differ between the two groups and consequently highlighting gait deficits in the amputees. Eight unilateral trans-tibial amputees and twelve able-bodied controls completed adaptive gait trials involving negotiating various height obstacles; with amputees leading with their prosthetic limb. Spatiotemporal variables that are regularly used to quantify how gait is adapted when crossing obstacles were determined and subsequently analysed using multivariate statistical techniques. There were fundamental differences in the adaptive gait between the two groups. Compared to controls, amputees had a reduced approach velocity, reduced foot placement distance before and after the obstacle and reduced foot clearance over it, and reduced lead-limb knee flexion during the step following crossing. Logistic regression analysis highlighted the variables that best distinguished between the gait of the two groups and multiple regression analysis (with approach velocity as a controlling factor) helped identify what gait adaptations were driving the differences seen in these variables. Getting closer to the obstacle before crossing it appeared to be a strategy to ensure the heel of the lead-limb foot passed over the obstacle prior to the foot being lowered to the ground. Despite adopting such a heel clearance strategy, the lead-foot was positioned closer to the obstacle following crossing, which was likely a result of a desire to attain a limb/foot angle and orientation at instant of landing that minimised loads on the residuum (as evidenced by the reduced lead-limb knee flexion during the step following crossing). These changes in foot placement meant the foot was in a different part of swing at point of crossing and this explains why foot clearance was considerably reduced in amputees. The results highlight that trans-tibial amputees use quite different gait adaptations to cross obstacles compared with controls (at least when leading with their prosthetic limb), indicating they are governed by different constraints; seemingly related to how they land on/load their prosthesis after crossing the obstacle.
Yes

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42

(10875660), Hamed Asadi. "Multi-Modal Sensing Approach for Objective Assessment of Musculoskeletal Fatigue in Complex Work." Thesis, 2021.

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Abstract:

Surface electromyography (sEMG) has been used to monitor muscle activity and predict fatigue in the workplaces. However, objectively measuring fatigue is challenging in complex work with unpredictable work cycles, where sEMG may be influenced by the dynamically changing posture demands. The sEMG is affected by various variables and substantial change in mean power frequencies (MPF), and a decline over 8-9% is primarily considered musculoskeletal fatigue. These MPF thresholds have been frequently used, and there were limited efforts to test their appropriateness in determining musculoskeletal fatigue in live workplaces (which predominantly consist of complex tasks). In addition, the techniques that consider both muscular and postural measurements that incorporate dynamic posture changes observed in complex work have not yet been explored. The overall objective of this work is to leverage both postural and muscular cues to identify musculoskeletal fatigue in complex tasks/jobs (i.e., tasks involving different levels of exertions, durations, and postures). The work was completed in two studies.

The first study aimed to (1) predict subjective fatigue using objective measurements in non-repetitive tasks, (2) determine whether the musculoskeletal fatigue thresholds in non-repetitive tasks differed from the previously reported threshold, and (3) utilize the empirically calculated thresholds to test their appropriateness in determining musculoskeletal fatigue in live surgical workplaces. The findings showed that the multi-modal measurements indicate better sensitivity than single-modality (sEMG) measurements in detecting decreases in MPF, a predictor of fatigue. In addition, the results showed that the thresholds in dynamic non-repetitive tasks, like surgery, are different than the previously reported 8% threshold. Additionally, implementing muscle-specific thresholds increased the likelihood of more accurately reporting subjective fatigue. The second study aimed to develop a multi-modal fatigue index to detect musculoskeletal fatigue. A controlled laboratory study was performed to simulate the non-repetitive physical demands at different postures. A series of experiments were conducted to test the effectiveness of various metrics/models to identify subjective fatigue in complex tasks. Next, the composite fatigue index (CFI) function was developed using the time-synced integration of both muscular signals (measured with sEMG sensors) and postural signals (measured with Inertial Measurement Unit (IMU) sensors). The variables from sEMG (amplitude, frequency, and the number of muscles showing signs of fatigue) and IMU (the prevalence of static and demanding postures and the number of shoulders in static/demanding posture) sensors were integrated to generate the CFI function. The prevalence of static/demanding postures was developed using the cumulative exposures to static/demanding postures based on the material fatigue failure theory. The single value fatigue index was obtained using the resultant CFI function, which incorporates both muscular and postural variables, to quantify the muscular fatigue in dynamic non-repetitive tasks. The findings suggested that the propagation of musculoskeletal fatigue can be detected using the multi-modal composite fatigue index in complex tasks. The resultant CFI function was then applied to surgery tasks to differentiate the fatigued and non-fatigued groups. The findings showed that the multi-modal fatigue assessment techniques could be utilized to incorporate the muscular and postural measurements to identify fatigue in complex tasks beyond single-modality assessment approaches.

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43

Buckley, John G., G. Cooper, C. N. Maganaris, and N. D. Reeves. "Is stair descent in the elderly associated with periods of high centre of mass downward accelerations?" 2012. http://hdl.handle.net/10454/9630.

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Abstract:

No
When descending stairs bodyweight becomes supported on a single limb while the forwards-reaching contralateral limb is lowered in order to make contact with the step below. This is associated with lowering of the centre of mass (CoM), which in order to occur in a controlled manner, requires increased ankle and knee joint torque production relative to that in overground walking. We have previously shown that when descending steps or stairs older people operate at a higher proportion of their maximum eccentric capacity and at, or in excess of the maximum passive reference joint range of motion. This suggests they have reduced and/or altered control over their CoM and we hypothesised that this would be associated with alterations in muscle activity patterns and in the CoM vertical acceleration and velocity profiles during both the lowering and landing phases of stair descent. 15 older (mean age 75 years) and 17 young (mean age 25 years) healthy adults descended a 4-step staircase, leading with the right limb on each stair, during which CoM dynamics and electromyographic activity patterns for key lower-limb muscles were assessed. Maximum voluntary eccentric torque generation ability at the knee and ankle was also assessed. Older participants compared to young participants increased muscle co-contraction relative duration at the knee and ankle of the trailing limb so that the limb was stiffened for longer during descent. As a result older participants contacted the step below with a reduced downwards CoM velocity when compared to young participants. Peak downwards and peak upwards CoM acceleration during the descent and landing phases respectively, were also reduced in older adults compared to those in young participants. In contrast, young participants descended quickly onto the step below but arrested their downward CoM velocity sooner following landing; a strategy that was associated with longer relative duration lead-limb plantar flexor activity, increased peak upwards CoM acceleration, and a reduced landing duration. These results suggest that a reduced ability to generate high eccentric torque at the ankle in the forward reaching limb is a major factor for older participants adopting a cautious movement control strategy when descending stairs. The implications of this CoM control strategy on the incidences of falling on stairs are discussed.

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Dissertations / Theses on the topic 'Human Postural Analysis'

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