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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.
391

Efeitos de um progama de treinamento de caminhada livre e caminhada nórdica em idosos sedentários / Effects of a Nordic walking and free walking training program on static and dynamic balance parameters, self-selected walking speed, locomotor rehabilitation index and quality of life of sedentary elderly : a randomized controlled trial

Gomeñuka, Natalia Andrea January 2016 (has links)
Introdução: Considerando o rápido aumento da população de idosos e da sua expectativa de vida, junto com a expansão das intervenções de caminhada nórdica (NW) como método de treinamento para idosos, há uma necessidade de estudos de base experimental (ensaios clínicos randomizados controlados, ECRs) de caráter preventivo e de boa qualidade metodológica que permitam aos profissionais da educação física, da saúde e da reabilitação a tomada de decisões relativas ao tipo, volume, intensidade de exercício da NW na promoção da saúde dos idosos sedentários. Objetivos: o presente estudo teve como objetivos (estudo A) determinar, por meio de revisão sistemática de ensaios clínicos randomizados, se o treinamento sistematizado com NW, comparado à caminhada livre (CL), produz efeitos benéficos sobre componentes da aptidão funcional de idosos sedentários saudáveis, também avaliar (estudo B) os efeitos de oito semanas de treinamento de NW e CL na qualidade de vida (QV), no equilíbrio estático, na variabilidade dinâmica, na velocidade autosselecionada de caminhada (VAS) em esteira e no índice de reabilitação locomotor (IRL) de idosos sedentários, e também avaliar (estudo C) os efeitos de oito semanas de treinamento de NW e CL no trabalho mecânico (externo- Wext, trabalho mecânico interno- Wint, no trabalho mecânico total – Wtot), no mecanismo pendular (R), no Custo de transporte (C), na frequência cardíaca de exercício (FCexercício), na sensação subjetiva de esforço (RPE), e nos parâmetros eletromiográficos (amplitude média do sinal e co-contração) dos músculos: deltoides anterior (DA), tríceps braquial (TB), vasto lateral (VL), bíceps femoral (BF), tibial anterior (TA) e gastrocnêmio medial (GM) de idosos sedentários. Desenho Experimental: ECR. Local da Pesquisa: Escola de Educação Física, Fisioterapia e Dança (ESEFID) da Universidade Federal do Rio Grande do Sul Porto Alegre, Rio Grande do Sul, Brasil. Métodos: Participaram deste estudo 32 idosos sedentários randomizados em dois grupos (grupo NW), n=16, idade: 64,6±4,1 anos, massa: 81,5±10,7kg e estatura: 166,3±7,5cm; e o grupo CL, n=16, idade: 68,6±3,9 anos, massa: 74,6±14,5kg e estatura: 161,6±10,3cm), realizaram treinamento de NW e CL durante 8 semanas. Desfechos do estudo A: foram avaliadaos com um estudo de revisão sistemática parâmetros da aptidão funcional de idosos (força e resistência dos membros superiores, força e resistência dos membros inferiores, mobilidade, flexibilidade dos músculos da coluna lombar e da região posterior da coxa, amplitude geral da articulação do ombro, resistência aeróbia e velocidade autosselecionada). Desfechos do estudo B: foram avaliados utilizando questionário de qualidade de vida, testes de equilibrio em plataforma de força e coleta cinemática 3D durante caminhada em esteira rolante para determinação dos Parâmetros funcionais (qualidade de vida, equilíbrio estático e dinâmico, velocidade autosselecionada de caminhada e índice de reabilitação locomotor). Desfechos do estudo C: foram avaliados através coletas de dados espirométricos, cinemáticos 3D e eletromiográficos da caminhada em esteira rolante em diferentes velocidades os parâmetros mecânicos e do mecanismo pendular (trabalho mecânico externo, interno e total- Wext, Wint, Wtot, Recovery -R, Custo de transporte -C, Velocidade autosselecionada -VAS), parâmetros eletromiográficos (amplitude média do sinal e co-contração dos músculos DA, TB, VL, BF, TA e GM), frequência cardíaca de exercício – FCexercício, e sensação subjetiva de esforço - RPE, de idosos sedentários,. Análise Estatística: Os dados de descrição da amostra, no baseline, foram comparados aplicando-se ANOVA one-way. Os desfechos foram analisados utilizando as Equações de Estimativas Generalizadas (GEE), para a comparação entre os grupos (NW e CL) e os momentos (pré e pós treino). Utilizou-se um post-hoc de Bonferroni, para identificar as diferenças entre os efeitos e interações. Os dados foram apresentados em “model-based adjusted means”, e foram analisados com o software Statistical Package for the Social Science (SPSS) v.22.0. Adotou-se um nível de significância de α=0,05. Conclusão: os treinamentos de NW e de CL, promovem melhoras nos componentes da aptidão funcional; no equilíbrio estático e na variabilidade dinâmica de idosos. Contudo algumas diferenças entre as duas intervenções se relacionam ao princípio da especificidade do treinamento e ocorrem apenas nos componentes que receberam mais estímulos impostos pela técnica da caminhada com bastões, especialmente nos membros superiores. Ainda, o incremento da VAS na esteira aliada à utilização do IRL, nos permitem concluir que o treinamento de NW tem relevância clínica e é recomendado como meio de melhora do condicionamento físico e como método de reabilitação de idosos sedentários. Esta atividade física proporciona adaptações centrais com melhora significativa na mobilidade funcional de idosos. Deste modo, após treinamento de resistência aeróbica com e sem bastões os idosos aumentam a velocidade de locomoção nas atividades diárias e com menor custo metabólico devido às adaptações centrais e melhora do mecanismo pendular devido à maior proximidade da VAS à velocidade ótima de caminhada. Ainda há adaptações importantes na ativação muscular decorrentes do treinamento de NW em idosos indicando uma redução dos níveis de co-contração de membros superiores na caminhada sem bastões, à qual repercute diretamente na melhora da aptidão física, na independência funcional dos idosos. Além disso, recomendamos à NW como uma atividade física segura e efetiva para esta população quando a periodização do treinamento são realizados com o volume e intensidade estritamente controlados. / Introduction: Considering the rapid increase in the elderly population and their life expectancy, together with the expansion of Nordic walking (NW) interventions as a training method for the elderly, there is a need for experimental studies (randomized controlled trials, ECRs) of preventive character and of good methodological quality that allow the professionals of physical education, health and rehabilitation to make decisions regarding the type, volume and intensity of NW exercise in the health promotion of sedentary elderly. Objectives: This study aimed (study A) to determine, through a systematic review of randomized clinical trials, whether systematic training with NW, compared to free walking (FW), has beneficial effects on components of the functional capacity of sedentary elderly, also (study B) avaluate the effects of eight weeks of NW and FW training on quality of life (QoL), static balance, dynamic variability, self-selected walking speed on treadmill (SSWS) and Locomotor rehabilitation index (LRI) of sedentary elderly, and also evaluate (study C) the effects of eight weeks of NW and FW training on mechanical work (external, internal and total mechanical work -Wext,Wint, Wtot), pendular mechanism (R), Cost of (C), exercise heart rate (HRexercise), rate of perceived exertion (RPE), and electromyographic parameters (mean signal amplitude and co-contraction) of muscles: Anterior Deltoid (AD), Triceps Brachii (TB), Vastus Lateralis (VL), Femoral Biceps (BF), Anterior Tibialis (TA) and Medial Gastrocnemius (MG) of sedentary elderly. Experimental Design: Controlled Clinical Trial (ECR). Research Location: School of Physical Education, Physiotherapy and Dance (ESEFID), Federal University of Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil. Methods: The sample comprised 33 sedentary participants randomly divided into two groups (NW group, n =16, age: 64.6 ± 4.1 years old, weight: 81.5 ± 10.7 kg and height: 166.3 ± 7.5 cm; and FW group, n =16, age: 68.6 ± 3.9 years, mass: 74.6 ± 14.5 kg and height: 161.6 ± 10.3 cm), performed NW and FW training for 8 weeks. Outcomes of Study A: Parameters of functional fitness of the elderly (upper limb strength and endurance, lower limb strength and endurance, mobility, lumbar spine and posterior hip muscle flexibility, general amplitude of the shoulder joint, aerobic endurance and self-selected speed). Outcomes of study B: Functional parameters (QoL, static and dynamic balance, SSWS and LRI).Outcomes of Study C: Mechanical parameters and pendular mechanism (Wext, Wint, Wtot, R, C, SSS), electromyographic parameters (mean signal amplitude and Co-contraction of AD, TB, VL, BF, AT and MG muscles), HRexercise RPE of sedentary elderly. Statistics Analysis: Sample description data, at baseline, were compared by applying one-way ANOVA. The outcomes were analyzed using Generalized Estimates (GEE), to compare the groups (NW and CL) and the moments (pre and post training). A Bonferroni post-hoc was used to identify the differences between effects and interactions. The data were presented in model-based adjusted means, and were analyzed with the software Statistical Package for the Social Science (SPSS) v.22.0. A significance level of α = 0.05 was adopted. Conclusion: NW and FW training, promotes improvements in functional fitness components; in the static balance and in the dynamic variability of the elderly. However, some differences between the two interventions are related to the principle of training specificity and occur only in the components that received the most stimuli imposed by the walking technique with poles, especially in the upper limbs. Furthermore, the increase in SSWS on the treadmill combined with the use of LRI allows us to conclude that NW training has clinical relevance and is recommended as a means of improving physical conditioning and as a method of rehabilitation of sedentary elderly. This physical activity provides central adaptations with significant improvement in the functional mobility of the elderly. Thus, after aerobic resistance training with and without poles, the elderly increase the speed of locomotion in daily activities and with lower metabolic cost due to the central adaptations and improvement of the pendulum mechanism due to the greater proximity of the SSWS to the optimal speed of walking. There are still important adaptations in muscle activation resulting from NW training in the elderly indicating a reduction in the levels of co-contraction of upper limbs in walking without walking poles, which directly affects the improvement of physical fitness and functional independence of the elderly. In addition, we recommend NW as a safe and effective physical activity for this population when the periodization of training is performed with the volume and intensity strictly controlled.
392

The Effect of Hand-Held Weights and Exaggerated Arm Swing on Heart Rate, Blood Pressure, and Ratings of Perceived Exertion during Submaximal Walking

Austen, Karen Christine 12 1900 (has links)
The purpose of this study was to investigate the effect of hand-weights and exaggerated arm swing on heart rate, blood pressure, and ratings of perceived exertion during submaximal walking. Twenty middle-aged (40- 59 years) female volunteers were given four submaximal treadmill tests at 3.0 mph and 0 grade. The four treatment conditions were as follows: 1) walking with unexaggerated arm swing (AS); 2) walking with unexaggerated arm swing with hand-held weights (ASHW); 3) walking with exaggerated arm swing (EAS), and 4) walking with exaggerated arm swing with hand-held weights (EASHW). The testing sequence was randomized and a minimum of 48 hr was given between tests.
393

Investigations on Dynamics and Control of a Rimless Wheel Based 2D Dynamics Walker using Pulsed Torque Actuation

Patnaik, Lalit January 2014 (has links) (PDF)
Wheeled systems are energy efficient on prepared surfaces like roads and tracks. Legged systems are capable of traversing different terrains but can be lossy. At low speeds and on off-road surfaces, legged systems using dynamic walking can be energy efficient. Towards this objective, the dynamics of the walker needs to be modelled and controlled. In addition, the braking and ground impact losses need to be minimized. This thesis presents analysis and experiments on the dynamics and control of a rimless-spoked-wheel based mobile robot (Chatur ∗) that belongs to a category between wheeled and legged systems. This rolling rimless wheel is effectively a 2D dynamic walker that serves as a platform for investigating the dynamics and energetics of inverted pendulum walking with constant step angle. A pulsed actuation torque is proposed for the system resulting in four torque regimes defined by the ratio of energy losses to available actuator torque. Five physical constraints that impose fundamental limits on the choice of operating points of a generic inverted pendulum walker are expounded and a method for locating optimal operating points is discussed. Chatur’s hardware design is elaborated and a control topology is proposed for pulsed actuation of the dual brushless dc (BLDC) motor driven platform with wheel synchronization. Various actuator torque profiles can be used to achieve dynamic ‘walking’ in a hub-actuated rimless wheel. The proposed pulsed actuation torque gives rise to four torque regimes that achieve sustained walking and a fifth regime where the walker keeps slowing down with each step. The regimes can be identified based on the fraction of stance phase for which the actuator is energized. Theoretical analysis and experimental results are presented. A simple closed-form analytical solution, using hyperbolic functions, is proposed for the stance phase inverted pendulum dynamics considering planar motion. Ground impacts are assumed to cause abrupt drop in velocity. A constant braking torque that lumps together the effect of several loss phenomena is also considered. Based on whether the CoM is rising or falling and whether or not there is an actuating torque, a stance phase can have four types of sub-phases — actuated rise, unactuated rise, actuated fall, unactuated fall. These are concatenated in four different ways to form repeating cycles yielding the four regimes. The experimental set-up is a fixed step-angle walker constructed using two synchronized adjacent rimless wheels independently actuated at the hub. Varying the magnitude and duty ratio of the torque pulse, the four proposed regimes are experimentally shown. The mechanical power consumption and cost of transport are computed from measured motor currents for different average forward speeds. Videos of the walks are also taken. The space of operating points for an inverted pendulum based bipedal dynamic walker in terms of constraints and optimality is investigated. The operating point of the walker can be specified by the combination of initial mid-stance velocity (v0) and step angle (φm) chosen for a given walk. Not all operating points lead to a realizable steady-state gait. Using basic mechanics, a framework of physical constraints that limit the choice of operating points is proposed. The constraint lines thus obtained delimit the valid region of operation of the walker in the v0–φm plane. Within this allowable region, sub-regions that result in various regimes of walking are identified. A given average forward velocity vx,avg can be achieved by several combinations of v0 and φm. Only one of these combinations results in the minimum mechanical power consumption and can be considered the opti-mum operating point for the given vx,avg. A method is proposed for obtaining this optimal operating point based on tangency of the power and velocity contours. Putting together all such operating points for various vx,avg, a family of optimum operating points, called the optimal locus, is obtained. For the energy loss and internal energy models chosen, the optimal locus obtained has a largely constant step angle with increasing speed but tapers off at non-dimensional speeds close to unity. Thus, choosing the right step angle and keeping it fixed over a broad range of speeds could lead to an inverted pendulum walker that is close to optimal from a mechanical energy perspective. The complete hardware design for Chatur and the caveats associated with reliable performance of the mechanical and electrical subsystems are elaborated. In order to en-sure lateral stability, the system uses two contralateral wheels each driven by a separate BLDC hub motor. From a motor drive perspective, the mechanical load belongs to a unique class of dynamic loads whose reflected torque has a characteristic cyclic varia-tion that repeats several times within a mechanical revolution. The proposed control topology has two hierarchical levels, an inner loop for torque control of BLDC motor implemented using a standard proportional-integral controller, and an outer loop for torque reference generation that uses the information on the ground impact instants and the motor position feedback. Ground impacts of the spokes are detected by an accelerometer to initiate the application of torque. The torque pulse magnitude can be set internally or by a manual operator via radio control. The pulse duration is programmable and enables attainment of various torque regimes at different steady state speeds. The wheels are synchronized so that corresponding spokes on both wheels move in unison. This is achieved by including a wheel synchronization loop that compensates for any lag between the wheels. Lag is detected based on number of sector changes in the hall-effect position sensor data received from both motors. An improved BLDC motor drive is developed wherein non-commutating current feedback is used to reduce current spikes during sector transitions. Experimental waveforms for controller validation are shown.
394

Konstrukce kráčejícího mobilního robotu / Design of walking mobile robot

Szabari, Mikuláš January 2018 (has links)
The diploma thesis deals with the construction of a walking mobile robot, which is intended for passing through a rugged or forest terrain, whose task is to collect the sample. The first part is devoted to the review of walking robots. Follow-up an analysis of two-legged and four-leg walking robot technologies and a brief overview of drives. The second part is devoted to problem analysis and design variant. The work contains 4 design variants in the form of schemes. Using the multi-criteria analysis, the variants were evaluated and the optimal variant was chosen taking into account the representative parameters. The third part is devoted to the construction of the chosen variant, it is divided into body and leg construction. The overall design is processed in the form of a virtual 3D model. In the leg construction, the design itself, but also the calculations of drives, shafts, gears and belt transmissions are solved. The end of the thesis is devoted to drawing documentation based on 3D model and economic evaluation. Follow-up and discussion with possible continuation and use in practice.
395

Contribution à la commande corps-complet des robots humanoïdes : du concept à l'implémentation temps-réel / Contribution to whole-body control of humanoid robots : From concept to real time implementation

Galdeano, David 13 November 2014 (has links)
Les robots humanoïdes sont en passe d'être commercialisés pour le public à grande échelle, mais pour réussir cet objectif il est nécessaire de rendre ces robots fiables, fonctionnels et sécurisés. Ceci implique de nombreuses améliorations par rapport à de l'état de l'art, pour permettre un produit fini. Un des domaines à améliorer est la commande corps-complet des robots humanoïdes. Les objectifs de cette thèse sont de proposer une architecture de commande permettant de générer des mouvements corps-complet bio-inspirés. L'idée principale étant de s'inspirer de la marche humaine afin de reproduire ces mouvements sur un robot humanoïde. La solution de commande proposée utilise le principe de tâches pour quatre objectifs cinématiques: (i) la pose relative des pieds, (ii) la position du CoM, (iii) l'orientation du buste, et (iv) l'évitement des butées articulaires. La stabilité est renforcée en modifiant la position du CoM désirée à l'aide d'un stabilisateur basé sur la régulation non linéaire du ZMP. L'approche résultante est appelée architecture de commande hybride cinématique/dynamique. Cette approche a été validée expérimentalement sur deux prototypes de robots humanoïdes pour différentes tâches telles que le squat et la marche. / Humanoid robots are a rising trend, and are about to be sold to the public on a large scale, but for this to be possible it is necessary to make them reliable, secure and functional. This implies many improvements over the prior state of the art. A domain of improvement is the full-body control of humanoid robots. The objective of this thesis is to propose a control architecture for generating a bio-inspired full-body control. The main idea is to learn from human walking to replicate these movements on a humanoid robot. The proposed control solution uses the principle of kinematics task for four objectives: (i) the relative pose of the feet, (ii) the position of the Centre de masse (CoM), (iii) the orientation of the upper-body, and (iv) the joints' limits avoidance. Stability is enhanced by modifiying the CoM position by using a stabilizer based on nonlinear regulation of the Zero Moment Point (ZMP). The resulting approach is called hybrid kinematic / dynamic control architecture. This approach has been validated experimentally on two prototypes of humanoid robots for tasks such as squat and walking.
396

An analysis of walking and bicycling behavior in suburban multifamily housing: A case study in Eugene, Oregon

Belanger, Kevin M., 1985- 12 1900 (has links)
xi, 63 p. : ill. (some col.) A print copy of this thesis is available through the UO Libraries. Search the library catalog for the location and call number. / Walking, bicycling, and other modes of active transportation can be utilitarian modes of personal transport, but barriers exist that limit the ability of groups of people to use these modes. This research looks at the walking and bicycling behaviors and attitudes of residents of suburban multifamily housing, a housing type identified in previous literature as needing research. Particularly, the roles of pedestrian route distance and directness as well as physical route characteristics are explored in their effects on walking and bicycling behavior. Results show that both the pedestrian network distance and major arterials are significantly correlated with a person's mode choice. Recommendations include increasing density around suburban commercial centers and encouraging pedestrian and bicycle connections between developments to limit arterial interaction. / Committee in Charge: Nico Larco, Chair; Dr. Marc Schlossberg; Dr. Kathryn A. Lynch
397

The Prediction Of Field Cricket Phonotaxis In Complex Acoustic Environments

Mhatre, Natasha 12 1900 (has links)
Animals detect, recognize and localize relevant objects in noisy, multi-source environments. Female crickets locate potential mates in choruses of simultaneously calling males using acoustic signals, a behaviour termed phonotaxis. The mechanisms underlying cricket phonotaxis are now understood across multiple levels: biophysical, neurobiological and behavioural. Phonotaxis has, however, rarely been tested in the complex real-world acoustic environments and no attempts have been made to predict acoustic orientation behaviour in these conditions despite our extensive understanding of its underlying mechanisms. In this thesis, I first characterized the acoustic environments faced by female crickets of the species Plebeiogryllus guttiventris in the field. Phonotaxis behaviour of females was then characterized under laboratory conditions using two sound sources. The data obtained were used to develop a simulation that predicted this behaviour. The predictions of the simulation were then tested against the phonotaxis behaviour of females in realistic, multi-source conditions in the field. My field studies of male behaviour showed that males of this species produced complex and variable songs in choruses where multiple males called simultaneously. The acoustic ranges of males in these choruses overlapped extensively and females performing phonotaxis in such choruses would hear multiple males simultaneously. The acoustic interactions of simultaneously calling males were also characterized for their timing relationships with each other and the changes they made to the temporal patterns of their songs. Males did not either synchronise or alternate their chirps, however they made changes to the temporal patterns of song in a way that is likely to make them more attractive to females. I then characterized the closed-loop walking phonotaxis behaviour of P. guttiventris females in the presence of two active sound sources playing conspecific song. Both the baseline and relative SPLs of the two speakers were systematically varied and female phonotactic paths were obtained. Females were found to preferentially approach louder songs. Several aspects of this behaviour were characterized, in particular orientation ability and motor behaviour under varied conditions of stimulus intensity. A stochastic simulation of closed-loop walking phonotaxis behaviour was developed using both current understanding of field cricket physiology and my data on closed-loop walking phonotaxis. The simulation was demonstrated to both qualitatively and quantitatively recapture female behaviour. It was also able to qualitatively recapture female behaviour in two previously published classical experiments in which the hearing of female crickets was disrupted. Female phonotaxis was then tested under real-world multi-source conditions. The behaviour of real females was compared to the predictions of the simulation. The simulation was found to recapture both female preference and phonotactic path forms at the population level. To my knowledge, this is the first study to both examine and successfully predict phonotaxis behaviour in complex real-world acoustic conditions.
398

Quadruped robot control and variable leg transmissions

Ingvast, Johan January 2006 (has links)
The research presented in this thesis regards walking of quadruped robots, and particularly the walking of the Warp1 robot. The motivation for the robot is to provide a platform for autonomous walking in rough terrain. The thesis contains six papers ranging from development tools to actuation of robot legs. The first paper describes the methods and tools made for control development. These tools feature: programming of the robot without low level coding (C-code); that the controller has to be built only once for simulation and experiments; and that names of variables and constants are unchanged through the chain of software Maple -- Matlab -- Simulink -- Real~Time~Workshop -- xPC--Target. Three controllers, each making the robot walk are presented. The first controller makes the robot walk using the crawl gait. The method uses static stability as method for keeping balance and the instantaneous trunk motions are given by a concept using the so called weight ratios. A method for planning new footholds based on the positions of the existing footholds is also proposed and the controller experimentally verified. The second walking controller shows that the robot also can walk dynamically using the trot gait. The method proposed uses information from ground contact sensors on the feet as input to control balance, instead of, which is common, inertial sensors. It is experimentally verified that Warp1 can trot from level ground onto a slope and turn around while staying balanced. The main ideas of these two walking controllers are fused in the third which enables smooth transitions between crawl and trot. The idea of using the ground contact sensors from the first controller is here used to estimate the position of the center of mass. This controller uses weight ratios in the gait crawl as well as in the dynamic gait trot. Hence, the method of using weight ratios is not only useful for static stability for which it was originally intended. The controller is experimentally verified on Warp1. The Warp1 robot weighs about 60 kg, has 0.6 m long legs with three actuated joints on each. The speed and strength is sufficient only for slow walking, even though the installed power indicates that it should be enough for faster walking. The reason is that a walking robot often needs to be strong but slow when the feet are on the ground and the opposite when in the air. This can not be achieved with the motors and transmissions currently used. A transmission called the passively variable transmission (PVT) is proposed which enhance motor capabilities of robot joints. It is elastic, nonlinear and conservative. Some general properties for elastic transmissions are derived such that they can be compared with conventional transmissions. The PVT gives strong actuation at large loads and fast actuation at small loads. The proposed transmission is compared to a conventional transmission for a specific task, and the result is that a smaller motor can be used. / QC 20100831
399

Walking for transportation : estudio de los factores individuales y contextuales que influyen en el caminar como medio de transporte y de sus implicaciones en salud

Olabarria Saenz de Viguera, Marta, 1982- 08 May 2013 (has links)
Desplazarse a pie es una actividad física moderada, rutinaria e integrada en la vida diaria que podría convertirse en una herramienta para disminuir la tendencia creciente del sedentarismo de la población. El objetivo de esta tesis es valorar el potencial en salud de la movilidad a pie como fuente de actividad física, y estudiar los factores individuales y contextuales que influyen en caminar como transporte. Para ello, se han llevado a cabo tres estudios. En el primero, utilizando la Encuesta de salud de Barcelona (ESB2011), se ha estudiado la relación entre la movilidad diaria y el sobrepeso o la obesidad; En el segundo, a partir de la Encuesta de Movilidad de Cataluña (EMQ2006) se ha estimado el beneficio económico derivado de la reducción de mortalidad resultante de sustituir desplazamientos motorizados cortos por caminar. Por último, también a partir de la Encuesta de Movilidad de Cataluña (EMQ2006) se ha estudiado la influencia de factores del entorno del barrio sobre la movilidad a pie. El cuerpo de esta tesis consta de 3 artículos científicos y otro artículo original en anexos que analiza específicamente la relación del género y la movilidad. Los estudios incluidos en esta tesis señalan como cambios concretos en la movilidad de poblaciones inactivas tienen efectos beneficiosos en salud, y podrían derivar en elevados beneficios económicos. Se han podido además identificar grupos poblacionales y factores del entorno susceptibles de intervención. / Walking for transportation is a moderate, routinely and daily integrated physical activity that could became a tool to decrease the current sedentarism of the population. The objective of this thesis is to analyze the potential in health of walking for transportation as a source of physical activity, and to study the individual and contextual factors that influence on the decision of walking for transport. Three studies were carried out. The first used the Barcelona Health Survey (ESB2011) to study the relationship between daily mobility and overweight or obesity; the second used the Cataluña Mobility Survey (EMQ2006) to estimate the economical benefits derived from the substitution of short duration motorized trips by walking. The third study, using again the Cataluña Mobility Survey (EMQ2006), looked at the influence of environmental factors on walking behavior. This thesis consists of three scientific papers included in the main section, and another original paper, included in the annex section, which analyzes the specific relationship between gender and mobility. The studies included in this thesis suggest that concrete behavioral changes on mobility in inactive populations could lead to several health benefits, and could also derive on economical benefits. In addition, population groups and environmental factors susceptible to intervention have been identified.
400

Just idag är jag stark : En anarkistisk och intersektionell studie av läktarkultur och politiskt identitetsskapande

Cullemo, Jenny January 2011 (has links)
This thesis explores the relationship between the Swedish autonomous left and the terrace culture of European football. It has its geographic starting point in Stockholm, Sweden and follows the three larges tStock­holm football clubs, AIK, Djurgården and Hammarby, and its supporters. The author has followed the football club Hammarby from the terrace for the entire 2011 football season, and has interviewed six political activists who visit, or used to visit, the terrace. The research context this study is incorporated into centres around the history of, and relationship between, the terrace cultures of AIK, Djurgården and Hammarby. Previous research has also focused on the radical potential of Ultras terrace culture (which is derived from Italian supporter culture) and the terrace culture from an intersectional perspective. Part of the aim of the thesis is to explore anarchist theory within an academic framework, something which has rarely been done before. The other main theoretical approach is largely based on the ideas of political theorist Chantal Mouffe and her exploration of the political identity formation of the subject in opposition to the deindividuating effect the mass can have on the individual. The method of the thesis is based on anarchist theories of participatory methods and on walking interviews developed by, among others, geographer Jon Anderson. What the research shows is that the presence of fascist values is much stronger on the terraces ofStockholmthan expected, and that the terrace culture as a whole has adopted a seemingly “apolitical” stance to try and submerge these. The participants’ stories centre on the inability to “loose oneself” in the mass of the terrace, and the feelings this inability awakens. This is the first thesis about the Ultras culture written in a Nordic context.

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