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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.
1

Recurrent Gait of Anthropomorphic, Bipedal Walkers

Shannon, Colleen Elizabeth 10 July 2003 (has links)
This thesis explores the dynamics of two bipedal, passive-walker models that are free to move in a three-dimensional environment. Specifically, two rigid-bodied walkers that can sustain anthropomorphic gait down an inclined plane with gravity being the only source of energy were studied using standard dynamical systems methods. This includes calculating the stability of periodic orbits and varying the system parameter to create bifurcation diagrams and to address the persistence of a periodic solution under specific parameter variations. These periodic orbits are found by implementing the Newton-Raphson root solving scheme. The dynamical systems associated with these periodic orbits are not completely smooth. Instead, they include discontinuities, such as those produced due to forces at foot contact points and during knee hyper-extension. These discontinuities are addressed in the stability calculations through appropriate discontinuity mappings. The difference between the two walker models is the number of degrees of freedom (DOF) at the hip. Humans possess three DOF at each hip joint, one DOF at each knee joint, and at least two DOF at each ankle joint. The first walker model studied had revolute joints at the hips and knees and completely locked ankles. To make the walking motion more anthropomorphic, additional degrees of freedom were added to the hip. Specifically, the second walker model has ball joints at the hips. Two control algorithms are used for controlling the local stability of periodic motions for both walker models. The methods, reference and delay feedback control, rely on the presence of discontinuities in the system. Moreover, it is possible to predict the effects of the control strategy based entirely on information from the uncontrolled system. Control is applied to both passive walker models to try and stabilize an unstable periodic gait by making small, discrete, changes in the foot orientation during gait. Results show that both methods are successful in stabilizing an unstable walking motion for a 3D model with one DOF in each hip and to reduce the instability of the walking motions for the model having more mobility in the hip joints. / Master of Science
2

Kinematic And Dynamic Modeling Of Human Walking

Karthick, G 11 1900 (has links) (PDF)
Walking comes naturally to us and appears to be simple. However, this is not so and it is known that walking requires high level neural control and muscle coordination. There is no single, unifying theory of bipedal walking. Models of walking are useful in various ways such as developing computational theories of neural control, understanding muscle coordination and to design and analyze lower extremity prostheses. This thesis deals with modeling and simulation of walking from a kinematics and dynamics view point. Three sagittal planar models with increasing levels of complexity are presented in this thesis. The first model is a simple two degrees of freedom (DoF) model representing the motion at the hip and the knee joint. The second model is a three DoF model where the ankle joint motion is also taken into account. Finally, the third model considers both the legs and has seven DoF. The kinematic and dynamic equations of the models are derived, and the inverse dynamic analysis and forward dynamic simulation of the models are performed. The simulation results are compared with experimental data available in literature.
3

Proposição e avaliação de um modelo de representação dos membros superiores e escapula durante a marcha humana / Proposition and evaluation of a model of the upper limbs and scapula representation durang the human gait

Araujo, Alethea Gomes Nardini 12 April 2009 (has links)
Orientador: Ricardo Machado Leite de Barros / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Educação Fisica / Made available in DSpace on 2018-08-14T03:55:20Z (GMT). No. of bitstreams: 1 Araujo_AletheaGomesNardini.pdf: 1729436 bytes, checksum: 0866174ca722c5ed18e3f01aa5215a5d (MD5) Previous issue date: 2003 / Resumo: A marcha humana é um movimento complexo que integra todos os segmentos corporais. Ela é objeto de pesquisa em laboratórios de todo o mundo e nestes o principal protocolo adotado, protocolo Helen Hays, analisa apenas o movimento dos membros inferiores e pelve e, através da interpretação dos resultados, muitos procedimentos invasivos e/ou conservadores podem ser prescritos. O objetivo geral deste trabalho é propor, avaliar e aplicar modelos de representação biomecânica dos membros superiores e escápula visando a análise de marcha. Um segundo objetivo é integrar os modelos propostos ao protocolo experimental para análise de marcha descrito por ANDRADE (2002). O corpo humano foi modelado como um sistema de quinze corpos rígidos articulados, cada um representando um segmento corporal. A cada segmento foi associado um sistema de coordenadas e a posição e a orientação relativas entre dois segmentos foram descritas, respectivamente, pela translação entre suas origens e pela rotação entre as bases a eles associadas. Os modelos de representação do braço e escápula adotados neste trabalho seguem a recomendação da Sociedade Internacional de Biomecânica. Foram avaliados três voluntários do sexo feminino, sem histórico de patologias ou comprometimento da marcha e dois voluntários do sexo masculino portadores de Paralisia Cerebral Diplégica. Os resultados foram avaliados a partir de testes de acurácia em relação à reconstrução da trajetória de dois marcadores durante a marcha e a acurácia encontrada foi de 2,4mm em um volume calibrado de 4,5m3, o que garantiu a confiabilidade dos resultados. Considerando um ciclo de marcha do membro inferior esquerdo observou-se, nos voluntários normais, que durante a fase de apoio, o ombro direito apresentou aumento da adução, extensão e rotação interna. Durante a fase de balanço, os ângulos mencionados diminuíram. O ombro esquerdo apresentou comportamento simétrico relacionado ao ciclo de marcha. Em relação ao cotovelo, os ângulos de abdução-adução e rotação internaexterna permaneceram constantes em ambos os lados. Um sinal claro de flexão pode ser observado durante todo o ciclo. A análise proposta foi capaz de identificar e caracterizar os padrões de marcha dos voluntários normais. Em relação aos voluntários patológicos, um paciente apresentou um padrão de marcha em crouch e ele revelou um comportamento aproximadamente simétrico considerando os membros superiores do lado direito e esquerdo. O outro paciente apresentou rotação interna aumentada no quadril e pé esquerdo associado a uma rotação do tronco para o lado direito. O cotovelo e o ombro do lado direito apresentaram pequena mobilidade provavelmente para compensar a rotação do tronco para este lado. Os resultados obtidos a partir do protocolo proposto para os sujeitos normais e patológicos foram compatíveis com os dados da literatura em relação aos ângulos articulares dos membros inferiores e da pelve. Os resultados da movimentação dos membros superiores, escápula, tronco e cabeça dos voluntários com e sem alterações da marcha também mostraram coerência com a movimentação esperada pela análise visual e com os dados disponíveis na literatura. / Abstract: The human gait is a complex movement that integrates all body's segments. It is studied in various gait laboratories where the main protocol adopted is the Helen Hays protocol, which considers only the lower limbs and the pelvis movement. With the results obtained from this protocol, respective procedures are prescribed. The aim of this paper is to propose, evaluate and apply models of biomechanical representation of the upper limbs and the scapula, focusing on the gait analysis. The second aim is to integrate the proposed models to an experimental protocol for the gait analysis described by ANDRADE (2002). The human body was modeled as a system of fifteen articulated rigid bodies, each one representing a corporal segment. Each segment was associated to a coordinated system, and the relative position and orientation between two segments were described, by the translation between its origins and the rotation between the bases associated to them. The representation models of the arm and scapula adopted in this paper follow the recommendation of the International Society of Biomechanics. Three female volunteers without gait pathologies and two spastic diplegic cerebral palsy male patients were analyzed. The results were evaluated from the tests of accuracy in relation to the reconstruction of the trajectory of two markers during the gait. The accuracy found was of 2,4mm in a calibrated volume of 4,5m³, thus guarantees the reliability of the results. Considering a left lower limb gait cycle during the stance phase, the right shoulder presented increasing adduction, extension and internal rotation, while during the swing phase these angles decreased. The left shoulder presented a symmetrical behavior related to the gait cycle. Regarding the elbow, the abductionadduction and internal-external rotation angles remain approximately constant in both sides. A clear signal of flexion can be observed during the cycle. The proposed analysis was able to identify and characterize the normal gait patterns of the normal studied subjects. Regarding the pathological subjects, one patient presented a crouch pattern gait and an approximately symmetrical gait by considering the right and left upper limbs. The other patient presented increased internal rotation on the left hip and in the left foot associated to a right rotation of the trunk. The right shoulder and elbow joints have small mobility, probably to compensate the increased rotation of the trunk to this side. The results obtained from proposed protocol for normal and pathological subjects were compatible with literature results concerning lower limbs and pelvis angles. The upper limbs, scapula, trunk and head results from volunteers without and with gait pathologies were coherent with their articulated motion in relation to visual analysis and to another published studies. / Universidade Estadual de Campi / Biodinamica do Movimento Humano / Mestre em Educação Física
4

Komparace koordinačních charakteristik kroku při chůzi na běžeckém trenažéru a v terénu / Comparison of the coordination characteristics of the step of walking on the run trainer and on the natural ground

Dančová, Štěpánka January 2014 (has links)
Title: Walking step coordination characteristic comparison for walking on running simulator and off-road walking. Objectives: Goal of the thesis is to measure, analyze and evaluate data of activity and involvement of lower limb muscles for offroad walking and walking on running simulator. The measured characteristic will be intra-individually and extra-individually compared. Method: Surface polyelectromyography method for data measurement and kineziological movement analysis method for values comparison are used in the thesis. Ten muscles of lower limb (2  5 muscles on left and right lower limb) were chosen. Results: Ten lower limb muscles were chosen and their activity for walking on running simulator and offroad walking was measured by surface polyelectromyography method on ten sportsmen. The results indicate that chosen muscles participate on monitored movement. The analysis shows that the muscles activity follows the same order for each of tested sportsmen independently on the external condition (running simulator and offroad walking). The thesis that correlation of measured values is higher for running simulator have been confirmed. But m.gluteus.med. and m.glut.max. have variation in the activity of the involvement in the field and on the treadmill. Similar results have also m.vastus med....
5

Energetic efficiency and stability in bipedal locomotion: 3D walking and energy-optimal perturbation rejection

Clark, Barrett C. January 2018 (has links)
No description available.
6

System Identification around periodic orbits with application to steady state human walking

Wang, Yang 06 August 2013 (has links)
No description available.
7

Piezoelectric Energy Harvesting for Powering Wireless Monitoring Systems

Qian, Feng 26 June 2020 (has links)
The urgent need for a clean and sustainable power supply for wireless sensor nodes and low-power electronics in various monitoring systems and the Internet of Things has led to an explosion of research in substitute energy technologies. Traditional batteries are still the most widely used power source for these applications currently but have been blamed for chemical pollution, high maintenance cost, bulky volume, and limited energy capacity. Ambient energy in different forms such as vibration, movement, heat, wind, and waves otherwise wasted can be converted into usable electricity using proper transduction mechanisms to power sensors and low-power devices or charge rechargeable batteries. This dissertation focuses on the design, modeling, optimization, prototype, and testing of novel piezoelectric energy harvesters for extracting energy from human walking, bio-inspired bi-stable motion, and torsional vibration as an alternative power supply for wireless monitoring systems. To provide a sustainable power supply for health care monitoring systems, a piezoelectric footwear harvester is developed and embedded inside a shoe heel for scavenging energy from human walking. The harvester comprises of multiple 33-mode piezoelectric stacks within single-stage force amplification frames sandwiched between two heel-shaped aluminum plates taking and reallocating the dynamic force at the heel. The single-stage force amplification frame is designed and optimized to transmit, redirect, and amplify the heel-strike force to the inner piezoelectric stack. An analytical model is developed and validated to predict precisely the electromechanical coupling behavior of the harvester. A symmetric finite element model is established to facilitate the mesh of the transducer unit based on a material equivalent model that simplifies the multilayered piezoelectric stack into a bulk. The symmetric FE model is experimentally validated and used for parametric analysis of the single-stage force amplification frame for a large force amplification factor and power output. The results show that an average power output of 9.3 mW/shoe and a peak power output of 84.8 mW are experimentally achieved at the walking speed of 3.0 mph (4.8 km/h). To further improve the power output, a two-stage force amplification compliant mechanism is designed and incorporated into the footwear energy harvester, which could amplify the dynamic force at the heel twice before applied to the inner piezoelectric stacks. An average power of 34.3 mW and a peak power of 110.2 mW were obtained under the dynamic force with the amplitude of 500 N and frequency of 3 Hz. A comparison study demonstrated that the proposed two-stage piezoelectric harvester has a much larger power output than the state-of-the-art results in the literature. A novel bi-stable piezoelectric energy harvester inspired by the rapid shape transition of the Venus flytrap leaves is proposed, modeled and experimentally tested for the purpose of energy harvesting from broadband frequency vibrations. The harvester consists of a piezoelectric macro fiber composite (MFC) transducer, a tip mass, and two sub-beams with bending and twisting deformations created by in-plane pre-displacement constraints using rigid tip-mass blocks. Different from traditional ways to realize bi-stability using nonlinear magnetic forces or residual stress in laminate composites, the proposed bio-inspired bi-stable piezoelectric energy harvester takes advantage of the mutual self-constraint at the free ends of the two cantilever sub-beams with a pre-displacement. This mutual pre-displacement constraint bi-directionally curves the two sub-beams in two directions inducing higher mechanical potential energy. The nonlinear dynamics of the bio-inspired bi-stable piezoelectric energy harvester is investigated under sweeping frequency and harmonic excitations. The results show that the sub-beams of the harvester experience local vibrations, including broadband frequency components during the snap-through, which is desirable for large power output. An average power output of 0.193 mW for a load resistance of 8.2 kΩ is harvested at the excitation frequency of 10 Hz and amplitude of 4.0 g. Torsional vibration widely exists in mechanical engineering but has not yet been well exploited for energy harvesting to provide a sustainable power supply for structural health monitoring systems. A torsional vibration energy harvesting system comprised of a shaft and a shear mode piezoelectric transducer is developed in this dissertation to look into the feasibility of harvesting energy from oil drilling shaft for powering downhole sensors. A theoretical model of the torsional vibration piezoelectric energy harvester is derived and experimentally verified to be capable of characterizing the electromechanical coupling system and predicting the electrical responses. The position of the piezoelectric transducer on the surface of the shaft is parameterized by two variables that are optimized to maximize the power output. Approximate expressions of the voltage and power are derived by simplifying the theoretical model, which gives predictions in good agreement with analytical solutions. Based on the derived approximate expression, physical interpretations of the implicit relationship between the power output and the position parameters of the piezoelectric transducer are given. / Doctor of Philosophy / Wireless monitoring systems with embedded wireless sensor nodes have been widely applied in human health care, structural health monitoring, home security, environment assessment, and wild animal tracking. One distinctive advantage of wireless monitoring systems is to provide unremitting, wireless monitoring of interesting parameters, and data transmission for timely decision making. However, most of these systems are powered by traditional batteries with finite energy capacity, which need periodic replacement or recharge, resulting in high maintenance costs, interruption of service, and potential environmental pollution. On the other hand, abundant energy in different forms such as solar, wind, heat, and vibrations, diffusely exists in ambient environments surrounding wireless monitoring systems which would be otherwise wasted could be converted into usable electricity by proper energy transduction mechanisms. Energy harvesting, also referred to as energy scavenging and energy conversion, is a technology that uses different energy transduction mechanisms, including electromagnetic, photovoltaic, piezoelectric, electrostatic, triboelectric, and thermoelectric, to convert ambient energy into electricity. Compared with traditional batteries, energy harvesting could provide a continuous and sustainable power supply or directly recharge storage devices like batteries and capacitors without interrupting operation. Among these energy transduction mechanisms, piezoelectric materials have been extensively explored for small-size and low-power generation due to their merits of easy shaping, high energy density, flexible design, and low maintenance cost. Piezoelectric transducers convert mechanical energy induced by dynamic strain into electrical charges through the piezoelectric effect. This dissertation presents novel piezoelectric energy harvesters, including design, modeling, prototyping, and experimental tests for energy harvesting from human walking, broadband bi-stable nonlinear vibrations, and torsional vibrations for powering wireless monitoring systems. A piezoelectric footwear energy harvester is developed and embedded inside a shoe heel for scavenging energy from heel striking during human walking to provide a power supply for wearable sensors embedded in health monitoring systems. The footwear energy harvester consists of multiple piezoelectric stacks, force amplifiers, and two heel-shaped metal plates taking dynamic forces at the heel. The force amplifiers are designed and optimized to redirect and amplify the dynamic force transferred from the heel-shaped plates and then applied to the inner piezoelectric stacks for large power output. An analytical model and a finite model were developed to simulate the electromechanical responses of the harvester. The footwear harvester was tested on a treadmill under different walking speeds to validate the numerical models and evaluate the energy generation performance. An average power output of 9.3 mW/shoe and a peak power output of 84.8 mW are experimentally achieved at the walking speed of 3.0 mph (4.8 km/h). A two-stage force amplifier is designed later to improve the power output further. The dynamic force at the heel is amplified twice by the two-stage force amplifiers before applied to the piezoelectric stacks. An average power output of 34.3 mW and a peak power output of 110.2 mW were obtained from the harvester with the two-stage force amplifiers. A bio-inspired bi-stable piezoelectric energy harvester is designed, prototyped, and tested to harvest energy from broadband vibrations induced by animal motions and fluid flowing for the potential applications of self-powered fish telemetry tags and bird tags. The harvester consists of a piezoelectric macro fiber composite (MFC) transducer, a tip mass, and two sub-beams constrained at the free ends by in-plane pre-displacement, which bends and twists the two sub-beams and consequently creates curvatures in both length and width directions. The bi-direction curvature design makes the cantilever beam have two stable states and one unstable state, which is inspired by the Venus flytrap that could rapidly change its leaves from the open state to the close state to trap agile insects. This rapid shape transition of the Venus flytrap, similar to the vibration of the harvester from one stable state to the other, is accompanied by a large energy release that could be harvested. Detailed design steps and principles are introduced, and a prototype is fabricated to demonstrate and validate the concept. The energy harvesting performance of the harvester is evaluated at different excitation levels. Finally, a piezoelectric energy harvester is developed, analytically modeled, and validated for harvesting energy from the rotation of an oil drilling shaft to seek a continuous power supply for downhole sensors in oil drilling monitoring systems. The position of the piezoelectric transducer on the surface of the shaft is parameterized by two variables that are optimized to obtain the maximum power output. Approximate expressions of voltage and power of the torsional vibration piezoelectric energy harvester are derived from the theoretical model. The implicit relationship between the power output and the two position parameters of the transducer is revealed and physically interpreted based on the approximate power expression. Those findings offer a good reference for the practical design of the torsional vibration energy harvesting system.
8

Étude sur la remise en suspension de particules suite à la marche d’un opérateur / Particle resuspension due to human walking

Mana, Zakaria 09 December 2014 (has links)
Lors des interventions humaines pendant les arrêts de tranche des installations nucléaires d’EDF, on remarque une remise en suspension de certains radionucléides sous forme d’aérosols (1 µm < dp < 10 µm). Dans le cadre d’une augmentation des interventions effectuées de façon simultanée en bâtiment réacteur, il devient important de mieux comprendre la remise en suspension due à l’activité des opérateurs pour adapter leur radioprotection. Le but des travaux de cette thèse est de quantifier la remise en suspension des particules suite à la marche des opérateurs sur un sol faiblement contaminé. Pour cela, la démarche suivie consiste à coupler un modèle de remise en suspension aéraulique avec des calculs numériques d’écoulement sous une chaussure, puis à caractériser expérimentalement certains paramètres d’entrée du modèle (diamètre de particule, forces d’adhésion, mouvement de la chaussure).Le modèle de remise en suspension Rock’n’Roll proposé par Reeks et Hall (2001) a été choisi car il décrit de manière physique ce mécanisme et est basé sur le moment des forces appliquées à une particule. Il nécessite la maîtrise de paramètres d’entrée tels que la vitesse de frottement de l’air, la distribution des forces d’adhésion et le diamètre des particules.Concernant le premier paramètre, des simulations numériques d’écoulement ont été réalisées, à l’aide du code de calcul ANSYS CFX, sous une chaussure de sécurité en mouvement (numérisée par CAO 3D) ; les cartographies des vitesses de frottement obtenues donnent des valeurs de l’ordre de 1 m.s⁻ ¹ pour une vitesse angulaire moyenne de 200 °.s⁻ ¹ .Concernant le deuxième paramètre, des mesures AFM (Atomic Force Microscope) ont été réalisées avec des particules d’alumine ainsi que des particules d’oxyde de cobalt en contact avec des surfaces en époxy représentatives de celles rencontrées dans les installations d’EDF. L’AFM permet d’obtenir la distribution des forces d’adhésion et révèle une valeur moyenne bien plus faible que ce qui peut être calculé de façon théorique en utilisant par exemple le modèle JKR proposé par Johnson et al. (1971). De plus, cette technique, tenant compte des rugosités de surface, montre que plus la taille de la particule augmente, plus la moyenne des forces d’adhésion diminue. Enfin, l’analyse des mesures AFM a permis d’obtenir une corrélation liant la distribution des forces d’adhésion au diamètre des particules, remplaçant celle de Biasi et al. (2001) initialement utilisée dans le modèle Rock’n’Roll et permettant ainsi d’adapter le modèle aux particules et aux revêtements de sol étudiés. Le couplage, effectué dans le code de calcul ANSYS CFX, entre les calculs de vitesses de frottement et le modèle de remise en suspension, a permis de déterminer des taux de remise en suspension théoriques pour le cas d’un cycle unique de marche. Ce couplage a été dans un premier temps validé par une comparaison à l’expérience pour le cas simple d’une plaque en rotation dans un volume contrôlé. En complément, des expériences à l’échelle d’un local ventilé de 30 m³ ont été réalisées en marchant sur un revêtement époxy ensemencé en particules de tailles calibrées (1,1 µm et 3,3 µm). Ces expériences ont permis de mettre en évidence les paramètres influant la remise en suspension des particules, tels que la fréquence de pas et la taille des particules. / In nuclear facilities, during normal operations in controlled areas, workers could be exposed to radioactive aerosols (1 µm < dp < 10 µm). One of the airborne contamination sources is particles that are initially seeded on the floor and could be removed by workers while they are walking. During the outage of EDF nuclear facilities, there is a resuspension of some radionuclides in aerosol form (1 µm < dp < 10 µm). Since the number of co-activity will increase in reactors buildings of EDF, it becomes important to understand particle resuspension due to the activity of the operators to reduce their radiation exposure. The purpose of this Ph.D thesis is to quantify the resuspension of particles due to the progress of operators on a contaminated soil. Thus, the approach is to combine an aerodynamic resuspension model with numerical calculations of flow under a shoe, and then to characterize experimentally some input parameters of the model (particle diameter, adhesion forces, shoes motion).The resuspension model Rock'n'Roll proposed by Reeks and Hall (2001) was chosen because it describes physically the resuspension mechanism and because it is based on the moment of forces applied to a particle. This model requires two input parameters such as friction velocity and adhesion forces distribution applied on each particle.Regarding the first argument, numerical simulations were carried on using the ANSYS CFX software applied to a safety shoe in motion (digitized by 3D CAO); the mapping of friction velocity shows values of about 1 m.s⁻ ¹ for an angular average velocity of 200 °.s⁻ ¹ . As regards the second parameter, AFM (Atomic Force Microscopy) measurements were carried out with alumina and cobalt oxide particles in contact with epoxy surfaces representative of those encountered in EDF power plants. AFM provides the distribution of adhesion forces and reveals a much lower value than what can be calculated theoretically using JKR model (Johnson et al. (1971)). Moreover, this technique, taking into account the surface roughness, shows that adhesion forces decrease while particle diameter increase. Finally, the analysis of AFM measurements gives a correlation linking the distribution of adhesion forces to the particle diameter, replacing the one given by Biasi et al. (2001) originally used in the Rock'n'Roll model and thereby adapt the model to particles and flooring studied in our case.Coupling, performed in ANSYS CFX software, between the calculations of friction velocity and model of particle resuspension, gives theoretical resuspension rate during shoe motion. This coupling was initially validated by comparison to the experience for the simple case of a rotating plate in a controlled volume. Secondly, experiments at the scale of a ventilated room of 30 m³ were performed by walking on an epoxy coating initially seeded by calibrated particle size (1,1 µm and 3,3 µm). These experiments highlight the parameters influencing the suspension of particles, such as step frequency and particle size.
9

Modèle d'isochrones automatisé du mouvement potentiel des personnes portées disparues

Blanco, Miguel Alfonso January 2016 (has links)
Résumé : Au Canada, annuellement il y a près de 10 000 personnes disparues. Pour les retrouver chaque fois une alerte est donnée. La police et les groupes de recherche terrestre spécialisés travaillent pour la retrouver, mais, par où commencer? Dans quelles directions orienter les recherches? Combien du temps pour balayer les différents secteurs? C’est souvent une question d’heures ou même des minutes pour la retrouver vivante. La théorie de recherche a trois concepts essentiels; la probabilité d’aire, la probabilité de détection et la probabilité de succès. Notre travail a cherché à préciser la probabilité d’aire. L’objectif de ce travail de recherche a consisté à développer un algorithme pour élaborer des cartes d’isochrones automatiques de la vitesse de marche probable des disparus. Il tient compte des restrictions dues aux variables environnementales (relief, occupation du sol, météorologie) et anthropiques (âge, sexe, taille, poids et activité physique). Le travail est développé au tour d’un système d’information géographique. Sur ceci nous distinguons deux groupes des données. Le premier correspond aux données attributaires que servent à générer la zone tampon et les facteurs de vitesse de l’individu. Ces données sont attachées à la couche du point initial. Dans le deuxième groupe, nous trouvons les données à référence spatiale intérieures à la zone tampon. Les facteurs de vitesse de l’individu et la carte de pentes génèrent la carte de vitesses par superficie. Les données de couverture de sol, quant à elles, produisent la carte de coût de traversée de la superficie. Finalement, la multiplication des deux dernières cartes produit la carte de coût de voyage, laquelle est le résultat essentiel pour concevoir la carte des courbes isochrones. Un algorithme a été construit et développé en langage de programmation Python. Il a été exécuté avec des données saisies dans l’environnement d’ArcGis 10.2. Nous avons observé une tendance des disparus à rester dans un rayon d’une heure de marche à partir du point initial (Pl). De plus, des variables comme les routes, sentiers et lignes de transport d’énergie influencent la marche. Finalement nous avons trouvé que l’outil aide au confinement de la probabilité d’aire. L’outil se démarque par sa simplicité d’usage. À l’intégration des facteurs de marche qui sont reliés à l’individu. Ainsi qu’à l’inclusion des facteurs météorologiques. Il peut s’exécuter partout au Canada. / Abstract : In Canada, annually there are about 10 000 missing persons. To find them whenever a warning is given. Police and specialized ground search groups work to find her, but where to start? In what directions guide research? How much time to scan the different sectors? It is often a matter of hours or even minutes to find her alive. The search theory has three basic concepts; the probability of area, the probability of detection and probability of success. Our work has sought to precise the probability of area in land search. The aim of this research was to develop an algorithm to make automatic isochrone maps that show the probability walking time of the missing person. It takes account of restrictions due to environmental variables (topography, land use, meteorology) and anthropogenic (age, sex, height, weight and physical activity). The work was developed around a geographic information system. On top of this, we distinguish two groups of data. The first is the attribute data that are used to generate the buffer zone and the individual speed factors. These data are attached to the initial planning point layer. In the second group, we find the internal spatial data in the buffer zone. The individual factors of speed and slope map produced the speed map. Ground cover data generated the cost map of crossing the area. Finally, the multiplication of the last two maps produced the travel cost map, which is the last step to design the isochrone map. An algorithm has been built and developed in the Python programming language. It was performed with the data entered into the ArcGIS 10.2 environment. We observed a trend of lost persons to stay around an hour's walk from the initial planning point (IPP). In addition, variables such as roads, paths and power transmission lines affect the walking speed. We found that the tool aid to precise the containment of probability of area. The tool is distinguished by its ease of use. With the integration of walking factors that are connected to the lost persons. We include meteorological factors. It can run across Canada.
10

Low-dimensional modeling and analysis of human gait with application to the gait of transtibial prosthesis users

Srinivasan, Sujatha 22 June 2007 (has links)
No description available.

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