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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
251

Development of functional asymmetries in young infants : A sensory-motor approach

Domellöf, Erik January 2006 (has links)
Human functional laterality, typically involving a right-sided preference in most sensory-motor activities, is still a poorly understood issue. This is perhaps particularly true in terms of what underlying mechanisms that may govern lateral biases, as well as the developmental origins and course of events. The present thesis aims at investigating functional asymmetries in the upper and lower body movements of young human infants. In Study I, the presence of side biases in the stepping and placing responses and head turning in healthy fullterm newborns were explored. No evident lateral bias for the leg responses in terms of the first foot moved or direction of head turning was found. However, a lateral bias was revealed for onset latency in relation to the first foot moved in both stepping and placing. Asymmetries in head turning did not correspond to asymmetries in leg movements. In Study II, functional asymmetries in the stepping response of newborn infants were investigated in more detail by means of 3-D kinematic movement registration. Evident side differences were found in relation to smoother movement trajectories of the right leg by means of less movement segmentation compared to the left leg. Side differences were also found in relation to intralimb coordination in terms of stronger ankle-knee couplings and smaller phase shifts in the right leg than the left. In Study III, using the same movement registration technique, the kinematics of left and right arm movements during goal-directed reaching in infants were prospectively studied over the ages 6, 9, 12, and 36 months. Main findings included side differences and developmental trends related to the segmentation of the reaching movements and the reaching trajectory, as well as the distribution of arm-hand-use frequency. The results from Study I and II are discussed in relation to underlying neural mechanisms for lateral biases in leg movements and the important role of a thorough methodology in investigating newborn responses. Findings from Study III are discussed in terms of what they imply about the developmental origins for hand preference. An emphasis is also put on developmental differences between fullterm and preterm infants. Overall, the studies of the present thesis show that an increased understanding of subtle expressions of early functional asymmetries in the upper and lower body movements of young infants may be gained by means of refined measurements. Furthermore, such knowledge may provide an insight into the underlying neural mechanisms subserving asymmetries in the movements of young infants. The present studies also add new information to the current understanding of the development of human lateralized functions, in particular the findings derived from the longitudinal data. Apart from theoretical implications, the present thesis also involves a discussion with regard to the clinical relevance of investigating functional asymmetries in the movements of young infants.
252

Provedení golfového švihu u pacientů s amputací dolní končetiny / Golf swing in subjects with amputation of lower extremity

Richtrová, Michaela January 2014 (has links)
Author: Bc. Michaela Richtrová Tittle: Golf swing in subjects with amputation of lower extremity Objectives: The study aims at evaluation of the technique of golf swing used by patients with a different type and level of lower extremity amputation as compared to able-bodied golfers. Another objective is determination of the relation between individual phases of the golf swing and weight transfer, using different golf clubs, as compared to able-bodied golfers. Method: By its topic the work is a pilot study. The research has been divided into three descriptive case studies. The experimental group included two amateur golfers and one professional golfer. The control group was represented by an able-bodied golfer. Evaluation of kinematic parameters (trajectory of shoulders, hips, knee joints) was based on the Qualysis Motion Capture System. Evaluation of dynamic parameters (weight transfer) in the course of golf swing was made using two dynamometric Kistler platforms. Results: The measuring has demonstrated that in terms of both kinematics and dynamics, the mode of movement of a patient with a trans-tibial amputation during a golf swing corresponds to that of an able-bodied golfer. The same results were achieved by the patient also with the use of another type of golf club. A change, both in terms of...
253

Vliv nošení vysokých podpatků na postavení pánve / The effect of wearing high heel shoes on pelvis motion.

Bočková, Barbora January 2015 (has links)
Title The effect of wearing high heel shoes on pelvis motion Aim of the thesis The main aim of this thesis is the verification of the influence of wearing high heel shoes on pelvis motion in the sagittal plane, while walking on high heel shoes and walking on heel less shoes. After then, we want to monitori the impact of walking in these shoes on the trajectory of pelvis motion. Methods Objectification method was 3D record of human gait (= kinematic analysis), which was performed using the Qualisys Track Manager. In our thesis we used the method of comparison. The aim of the study is the comparison of parameters measured in different types of shoes (high heeled shoes, high heeled less shoes with barefoot gait) and the influence on pelvis motion in the sagittal plane. Measurements were carried out in the gym at the Faculty of Physical Education and Sport at ten probands. Results Pelvis tilt to retroversion was more significant when walking on heel less shoes compared with high heel shoes and barefooted walking, also an angle of the trunk and pelvis were most significantly diminished when walking on heel less shoes compared to barefooted walking and high heel shoes. Objectively, a larger deflection of pelvis trajectory while walking on high heel shoes was not confirmed compared to walking on heel less...
254

Vztah mezi projevem mozečkové dominance v podobě fyziologického zánikového syndromu na horních i dolních končetinách a lateralitou člověka / Manifestation of cerebellar dominance in the form of extinction physiological syndrome on upper and lower limbs and its relationship to human laterality

Rybář, Adam January 2015 (has links)
1 Title: Manifestation of cerebellar dominance in the form of extinction physiological syndrome on upper and lower limbs and its relationship to human laterality. Objectives: The aim of this diploma thesis is to determinate size of relationship between manifestation of cerebellar dominance in the form of extinction physiological syndrome and preference of limbs. Methods: A total of 27 individuals (male and female students of UK FTVS) were involved in the current quantitative research. We used indicators which were selected from Musalek's test battery (2013) to assess limb preferences. The evaluation of joint passivity asymmetry was based on angle and time parameters during walk and during controlled falls of forearm and shank on a constructed fall-machine. The movement was registered in real time by Qualisys Motion Capture System. For data analysis, descriptive statistics methods, paired t-test, level of statistical and substantive significance (Cohen's d) and tetrachoric coefficient of correlation were used. Results: Our research suggests that there is no significant difference in joint passivity when comparing preferred and non preferred limbs. Though it is necessary to take into consideration specifics and the size of research sample in which everybody was an active athlete. The result of tetrachoric...
255

Analýza lokomoce po implantaci totální náhrady kyčelního kloubu / Human locomotion after total hip replacement

Horáková, Alena January 2016 (has links)
Title: Human locomotion after total hip replacement Objectives: The aim of this thesis is to perform a gait analysis of patients after total hip replacement and to find out, how chosen temporo-spatial, kinetic and kinematic parameters change during the first half a year after the surgery. The deviations found in gait stereotypes of individual patients are further compared with results of international studies. Methods: The thesis is theoretical-empirical, with small number of patients. 3D kinematic gait analysis was performed by Qualisys system and ground reaction forces by two Kistler force plates. The following parameters are being monitored: length of step, stance phase duration, cadence, walking speed, lateral shift of the pelvis and trunk in standing phase, contralateral pelvic drop in standing phase of the leg, maximum range of motion of the hip joint in sagital plain, maximum of vertical and medio-lateral component of the ground reaction forces in the standing phase. Results: The highest side deviations between legs were found in 3 months after the surgery and remained until 6,5 months after the surgery. In this time period a lower value of the length of step, stance phase duration, maximum range of motion of the hip joint in sagital plain and also a higher lateral shift of the pelvis was...
256

Změny mechaniky pohybu koně v tahu při různé zátěži

PISCOVÁ MANDOVÁ, Paulína January 2019 (has links)
Cold-blooded horses find their use at present mainly in tensile work in forest stands. Motion mechanics plays the key role in estimating their potential for performing this activity. Subsequently, it is used in their selection and reproduction. In the process, applied load the horse is working with significantly influences the characteristics of a movement. Therefore, for horses doing tensile work, an objective assessment of their movement mechanics is important, not only during demonstration but also under a changing load. The aim of this study was to prepare and evaluate an experiment for assessing the quantitative characteristics of motion mechanics (step length, action height and running speed) of a cold-blooded horse with no load and with a load of different weight using videographic kinematic analysis. The data obtained were statistically processed to assess changes in step length, action height and running speed depending on the changing load. The results of our experiment showed that the step length decreases with increasing weight of the load. From an average value of 1.94 m at run without a load, it drops to an average value of 1.02 m at a maximum monitored load of 500 kg. A high dependence (r=-0.93) of the step length reduction on the tensile load was found. The dependence is strongly evincible (p<0.001). Changes in action height with increasing load weight are different for the forelimb and rear limb. The forelimb has an almost constant value (~ 0.08m) and no dependence (p=0.977) on the changing weight of the load has been demonstrated. The rear limb shows a strong correlation (p<0.001) to the increasing weight of the load. The correlation coefficient r=0.52 indicates only a slight dependence. This difference can be explained by different function and construction of the limb. The running speed derived from the horizontal marker from the tracking mark on the back is uniform in all observed cases and decreases from 1.95 m.s-1 to 1.19 m.s-1 with increasing weight of the load. The dependence is strongly evincible (p<0.001) and the correlation coefficient of r=-0.94 indicates a strong dependence. The results obtained from the horizontal head velocity component are very well matched to the spine results. The results provided by this method can be an invaluable tool in objective detection of utility and breeding potential of cold-blooded horse in tensile work. Based on these findings, we can recommend further development of videographic kinematic analysis application to objectify the evaluation of quantitative characteristics of motion mechanics for zootechnical and breeding practice.
257

Cinématique et dynamique galactiques / Galatics kinematics and dynamics

Leca, Jérôme 08 February 2019 (has links)
Les modèles galactiques auto-cohérents sont nécessaires pour analyser et interpréter les comptages d’étoiles, les distributions de densité stellaire et la cinématique stellaire, dans le but de comprendre la formation et l’évolution de notre Galaxie. Cette thèse a pour but de modifier et améliorer l’auto-cohérence dynamique du modèle galactique de Besançon (BGM) dans le cas d’un potentiel gravitationnel stationnaire et axisymétrique. Chaque orbite stellaire est modélisée en déterminant une troisième intégrale du mouvement de Stäckel. Une fonction de distribution de Shu généralisée avec trois intégrales du mouvement est utilisée pour modéliser la fonction de distribution stellaire. Cette nouvelle version du BGM est comparée avec la précédente version axisymétrique BGM2014 et nous trouvons que les deux versions ont des densités similaires pour chaque composante. L’auto-cohérence dynamique est améliorée et peut être testée en retrouvant les forces et le potentiel via les équations de Jeans appliquées à chaque fonction de distribution stellaire. Les forces sont retrouvées avec une précision meilleure que 1 % sur la plupart du volume galactique. / Dynamically self-consistent galactic models are necessary for analysing and interpreting star counts, stellar density distributions, and stellar kinematics in order to understand the formation and the evolution of our Galaxy. This thesis aims to modify and improve the dynamical self-consistency of the Besançon Galaxy model in the case of a stationary and axisymmetric gravitational potential. Each stellar orbit is modelled by determining a Stäckel approximate integral of motion. Generalised Shu distribution functions (DFs) with three integrals of motion are used to model the stellar distribution functions. This new version of the Besançon model is compared with the previous axisymmetric BGM2014 version and we find that the two versions have similar densities for each stellar component. The dynamically self-consistency is improved and can be tested by recovering the forces and the potential through the Jeans equations applied to each stellar distribution function. Forces are recovered with an accuracy better than 1 % over most of the volume of the Galaxy.
258

Planejamento cinemático-dinâmico de movimento com desvio local de obstáculos utilizando malhas de estados / Kinematic-dynamic motion planning with local deviation of obstacles using lattice states

Magalhães, André Chaves 06 June 2013 (has links)
Planejamento de movimento tem o propósito de determinar quais movimentos o robô deve realizar para que alcance posições ou configurações desejadas no ambiente sem que ocorram colisões com obstáculos. É comum na robótica móvel simplificar o planejamento de movimento representando o robô pelas coordenadas do seu centro e desconsiderando qualquer restrição cinemática e dinâmica de movimento. Entretanto, a maioria dos robôs móveis possuem restrições cinemáticas não-holonômicas, e para algumas tarefas e robôs, é importante considerar tais restrições juntamente com o modelo dinâmico do robô na tarefa de planejamento. Assim é possível determinar um caminho que possa ser de fato seguido pelo robô. Nesse trabalho é proposto um método de planejamento cinemático-dinâmico que permite planejar trajetórias para robôs móveis usando malhas de estados. Essa abordagem considera a cinemática e a dinâmica do robô para gerar trajetórias possíveis de serem executadas e livre de colisões com obstáculos. Quando obstáculos não representados no mapa são detectados pelos sensores do robô, uma nova trajetória é gerada para desviar desses obstáculos. O planejamento de movimento utilizando malhas de estados foi associado a um algoritmo de desvio de obstáculos baseado no método da janela dinâmica (DWA). Esse método é responsável pelo controle de seguimento de trajetória, garantindo a segurança na realização da tarefa durante a navegação. As trajetórias planejadas foram executadas em duas plataformas distintas. Essas plataformas foram utilizadas em tarefas de navegação em ambientes simulados interno e externo e em ambientes reais. Para navegação em ambientes internos utilizou-se o robô móvel Pioneer 3AT e para navegação em ambientes externos utilizou-se o veículo autônomo elétrico CaRINA 1 que está sendo desenvolvido no ICMC-USP com apoio do Instituto Nacional de Ciência e Tecnologia em Sistemas Embarcados Críticos (INCT-SEC). / Motion planning aims to determine which movements the robot must accomplish to reach a desired position or configuration in the environment without the occurrence of collisions with obstacles. It is common in mobile robotics to simplify the motion planning representing the robot by the coordinates of its center of gravity and ignoring any kinematic and dynamic constraint motion. However, most mobile robots have non-holonomic kinematic constraints, and for some tasks and robots, it is important to consider these constraints together with the dynamic model of the robot in task planning. Thus it is possible to determine a path that can actually be followed by the robot. Here we propose a method for kinematic-dynamic path planning using lattice states. This approach considers the kinematic and dynamic of the robot to generate generate feasible trajectories free of collisions with obstacles. When obstacles not represented on the map are detected by the sensors of the robot, a new trajectory is generated to avoid these obstacles. The motion planning using lattice state was associated with an obstacle avoidance algorithm based on the dynamic window approach (DWA). This method is responsible for trajectory tracking to ensure safety in navigation tasks. This method was applied in two distinct platforms. These platforms were used for navigation tasks in both indoor and outdoor simulated environments, as well as, in real environments. For navigation in indoor environments we used a Pioneer 3AT robot and for outdoor navigation we used the autonomous electric vehicle CaRINA1 being developed at ICMC-USP with support National Institute of Science and Technology in Critical Embedded Systems (INCT-SEC).
259

Efeitos da fisioterapia aquática e convencional sobre a marcha, aspectos clínicos e funcionais de sujeitos com estenose de canal lombar : ensaio clínico randomizado

Rosa, Karen Przybysz da Silva January 2016 (has links)
A Estenose de Canal Lombar (ECL) é caracterizada pela redução do espaço de elementos neurais ou vasculares da coluna lombar. Os sintomas incluem dor e/ou parestesia em membros inferiores, região lombar, e glúteos e Claudicação Intermitente Neurogênica. O tratamento conservador é a escolha inicial para o manejo de pacientes com ECL, por isso é importante a identificação de diferentes estratégias para o tratamento conservador, e a compreensão das alterações em parâmetros funcionais que estes tratamentos geram. O presente estudo objetivou comparar os efeitos de 24 sessões de Fisioterapia Aquática (GFA) e de Fisioterapia Solo (GFS) nos parâmetros espaço-temporais de marcha, equilíbrio, nível de dor percebida, incapacidade, capacidade física funcional, medo de movimento e níveis de depressão em indivíduos com ECL. Para observação das diferenças entre os grupos e momentos foi realizado o teste de Equações de Estimativa Generalizada no software SPSS versão 20.0. Para todas as análises o índice de significância adotado foi de 95% (α=0,05). Os níveis de incapacidade, dor, e estados depressivos reduziram, bem como a velocidade de caminhada autosselecionada e o índice de reabilitação locomotora aumentaram após as intervenções sem diferenças entre os grupos. O GFA apresentou melhora dos parâmetros espaço-temporais de marcha em velocidade fixa, redução da ingesta de medicação analgésica, e redução da média semanal de dor mais cedo que o GFS. O GFS demonstrou maior melhora da mobilidade funcional indicando um melhor equilíbrio após a intervenção em comparação ao GFA. Tratamentos fisioterapêuticos estruturados com associação de exercícios de estabilização de tronco, alongamentos e terapia manual mostram-se eficazes para melhora da incapacidade, dor, depressão e parâmetros de marcha em indivíduos com Estenose da Canal Lombar, sendo o meio aquático potencializador da resposta analgésica e da melhora em parâmetros espaço temporais de marcha e o solo potencializador da melhora do equilíbrio. / Lumbar Spinal Stenosis (LSS) is characterized by a reduction in the space of vascular and neuronal elements of the spinal canal space. Symptoms include pain and/or paresthesia in lower limbs, lumbar region and buttocks, and Neurogenic Intermittent Claudication. Conservative treatments are the choice for initial management of patients with LSS, therefore it is important to identify different conservative treatments strategies and understanding of the changes in functional parameters that those treatments cause. The present study aimed to compare the effects of 24 physiotherapy sections of Aquatic Physiotherapy (GFA) and Ground Physiotherapy (GFS) in spatiotemporal gait parameters, balance, perceived level of pain, disability, functional exercise capacity, fear of movement, and clinical depression in individuals with LSS. Generalized Estimating Equations were made to observe the differences between groups and moments on SPSS software version 20.0. For all tests, the significance level was 95% (α = 0,05). Disability, pain and depressive symptoms reduced and selfselected walking speed and locomotor rehabilitation index increased after interventions with no differences between groups. GFA improve spatiotemporal gait parameter in fixed speed, reduced analgesic medication, and show an earlier reduction in weekly pain. GFS improve functional mobility indicating a better balance in comparison to GFA. Physiotherapeutic treatments structured with the association of stabilization exercises, stretching exercises and manual therapy are efficient in improving disability, pain, depression and gait parameters in Lumbar Spinal Stenosis patients, water environment potentiate analgesic and spatiotemporal improvements, and land potentiate balance improvements.
260

Response on reinforced concrete structural elements to ballistic impact and contact detonations

Athanasiou, Evangelia January 2018 (has links)
Concrete is a widely studied material with a composite nature. It is used both in civil and military buildings and infrastructures. An issue of great importance is the protection of people from terrorist attacks that target critical infrastructure. Explosions, detonations and/or projectile impacts are some of the most severe actions a concrete structure can face. Experimental analysis is necessary in order to understand and predict the response of a structure to such dynamic and strain rate sensitive conditions. However, as the cost of performing experiments is significant and numerical simulations offer improved blast and impact analysis capabilities, there is an effort to limit experiments to validation purposes. In recent years, many researchers have studied the impact loads transferred to reinforced concrete (RC) structures both through direct projectile impacts or blast waves at both near and far field. The aim of the current study is twofold. First, to investigate contact detonations on this type of material (RC), since literature can provide us with limited information. Secondly, to assess the behaviour of the RC structure under combined ballistic impact and contact detonation of a very specific geometry of projectile (HESH) that exists currently on the market and behaves differently from the normal projectiles that consist of one single material. The author analysed and discussed in depth the response of RC members exposed to contact detonations. More precisely, the effect of the mass of explosive (C4) on pressures, impulses and energy balances. Also, she investigated the kinematic response of RC slabs and the structural role of the reinforcing bars. The driving force of this RC structures. Currently, the majority of studies regarding contact blast are focusing either on innovative types of concrete or normal concrete. However, normal concrete is investigated as a control parameter (to prove the effective resistance of the innovative material) rather than a detailed study on the behaviour of the material. Thereafter, the author analysed the response of a RC wall under the combined effect of kinetic energy (terminal ballistics) and contact detonation caused by the impact of a 90 mm HESH (High Explosive Squash Head) projectile fired from a distance of 70 m. The aim was to investigate the response of the structural member under the superposition of those two actions and analyse the combined effects of the impact velocity and detonation on the response of the structure. The numerical modelling is based on a Multi-Material-Arbitrary-Lagrangian-Eulerian approach (MMALE, using LS-DYNA) using the Winfrith concrete constitutive material model to investigate the dynamic response of the RC members under high strain rate conditions. The efficiency of the proposed numerical modelling is validated with experimental results - based on open-arena testing - and provided by the Royal Military Academy of Belgium. Some of the key findings of this research are that the increase of the amount of the explosive affects the damage failure of the RC members from flexural failure to shear failure. In addition, fitting curves that could be used in design, were proposed, that show the relation between the mass of explosive and the resulting pressures and impulses, within the tested range. In the case of the combined blast and impact scenario, the detonation was found to dominate the structural response of the RC slab.

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