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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.
91

Evaluating the conservation potential of urban and rural ecosystems for aquatic-breeding amphibians: a case study of two native frogs in southwestern British Columbia

Green, Jemma 27 September 2018 (has links)
The conservation of aquatic-breeding amphibian populations and their habitats is increasingly challenged by urban and rural development, which is occurring more intensively and more rapidly than ever before. Some species are now impacted by development throughout their range. This has forced a re-evaluation of the potential of developed landscapes for providing habitat and contributing to regional conservation strategies. For many amphibians, little is known about the criteria necessary for persistence in a developed landscape. Considerable variation in the physiology, habitat requirements, and movement behaviour of amphibians suggests that responses to habitat loss, alteration, and fragmentation are species-specific. In this thesis, I investigate species-habitat relationships for the northern red-legged frog (Rana aurora) and the Pacific chorus frog (Pseudacris regilla) in a mixed urban-rural landscape in southwestern British Columbia to evaluate the potential for species persistence despite urban and rural development throughout their range. I used repeat auditory surveys of the species’ breeding chorus to determine presence or absence at potential breeding wetlands. I then related species occurrence and abundance to characteristics of the aquatic and terrestrial environment measured at multiple spatial scales. Both species were found to use rural and urban wetlands, though R. aurora were rarely detected while P. regilla were common. Occurrence was best explained by characteristics of the terrestrial environment, rather than within-wetland characteristics, though influential terrestrial characteristics and their scale of impact differed between species. Within the context of the developed landscape, I identify species-specific positive and negative habitat associations and suggest the spatial scales at which management of these habitat characteristics will be most effective. These criteria may help to explain the species’ current distribution, prioritize management strategies, predict the effectiveness of habitat conservation and restoration projects, and inform development in municipalities seeking to maintain or enhance amphibian diversity. / Graduate / 2019-09-11
92

Procedural locomotion of multi-legged characters in complex dynamic environments : real-time applications / Locomotion procédurale de créatures à n-pattes dans des environnements complexes et dynamiques : vers des applications en temps réels

Abdul Karim, Ahmad 17 December 2012 (has links)
Les créatures à n-pattes, comme les quadrupèdes, les arachnides ou les reptiles, sont une partie essentielle de n’importe quelle simulation et ils participent à rendre les mondes virtuels plus crédibles et réalistes. Ces créatures à n-pattes doivent être capables de se déplacer librement vers les points d’intérêt de façon réaliste, afin d’offrir une meilleure expérience immersive aux utilisateurs. Ces animations de locomotion sont complexes en raison d’une grande variété de morphologies et de modes de déplacement. Il convient d’ajouter à cette problématique la complexité des environnements où ils naviguent. Un autre défi lors de la modélisation de tels mouvements vient de la difficulté à obtenir des données sources. Dans cette thèse nous présentons un système capable de générer de manière procédurale des animations de locomotion pour des dizaines de créatures à n-pattes, en temps réel, sans aucune donnée de mouvement préexistante. Notre système est générique et contrôlable. Il est capable d’animer des morphologies différentes, tout en adaptant les animations générées à un environnement dynamique complexe, en temps réel, ce qui donne une grande liberté de déplacement aux créatures à n-pattes simulées. De plus, notre système permet à l’utilisateur de contrôler totalement l’animation produite et donc le style de locomotion / Multi-legged characters like quadrupeds, arachnids, reptiles, etc. are an essential part of any simulation and they greatly participate in making virtual worlds more life-like. These multi-legged characters should be capable of moving freely and in a believable way in order to convey a better immersive experience for the users. But these locomotion animations are quite rich due to the complexity of the navigated environments and the variety of the animated morphologies, gaits, body sizes and proportions, etc. Another challenge when modeling such animations arises from the lack of motion data inherent to either the difficulty to obtain them or the impossibility to capture them.This thesis addresses these challenges by presenting a system capable of procedurally generating locomotion animations fordozens of multi-legged characters in real-time and without anymotion data. Our system is quite generic thanks to the chosen Procedural-Based techniques and it is capable of animating different multi-legged morphologies. On top of that, the simulated characters have more freedom while moving, as we adapt the generated animations to the dynamic complex environments in real-time. Themain focus is plausible movements that are, at the same time,believable and fully controllable. This controllability is one of the forces of our system as it gives the user the possibility to control all aspects of the generated animation thus producing the needed style of locomotion
93

Efeitos fisiológicos do treinamento unipodal em cicloergômetro com e sem irradiação LED / Physiological effects of one-legged cycling with and without LED therapy

Thiago Gomes Figueira 01 December 2017 (has links)
A melhora na capacidade física e/ou reserva funcional de um indivíduo deve-se, entre outros, a um treinamento sistemático e bem padronizado. O exercício aeróbio é uma modalidade frequentemente empregada em um programa de treinamento, especialmente naqueles com objetivo de melhora do condicionamento físico. Contudo atualmente, o uso da fototerapia tem ganhado espaço no que tange ao aumento de desempenho de atletas. Baseado nisso o objetivo deste estudo foi verificar o efeito do treinamento unipodal, terapia LED e treinamento associado à terapia LED sobre parâmetros ergoespirométricos de performance (VO2max, AT e RCT) e na concentração sanguínea de creatina quinase. Para esse estudo participaram 24 voluntários do sexo masculino, os quais foram submetidos a uma avaliação pré-intervenção, foram submetidos a um período de oito semanas de treinamento em cicloergômetro com irradiação LED ou placebo. Após esse período foram submetidos a uma nova avaliação, pós-treino. Para a aplicação da terapia LED, foi utilizado um arranjo contendo 50 LEDs com comprimento de onda de 850 nm e aplicado por 60 segundos após cada sessão de treino. Os voluntários foram separados nos seguintes grupos experimentais: Não Treinados e LED desligado (Grupo NTLD), Não Treinados e LED ligado (Grupo NTLL), Treinados e LED desligado (Grupo TLD), Treinados e LED ligado (Grupo TLL). A perna que recebeu a intervenção foi eleita por sorteio e foi chamada de perna ativa (A) e a perna contralateral, chamada de controle (C). Durante o teste em exercício crescente, até a fadiga, foram quantificadas as variáveis ergoespirométricas, ventilação (Ve), consumo de oxigênio (VO2), equivalente ventilatório de oxigênio (EqVO2), também foi coletada amostra de sangue para dosagem da lactacidemia e foi mensurada a concentração da enzima creatina quinase (CK). Como resultados das respostas agudas frente ao ato de pedalar com uma perna notou-se que a pedalada unipodal apresentou menor valor de intensidade, VO2, Ve, lactacidemia e maior incremento de CK, quando comparada com a pedalada bipodal (convencional). Ao se concluir as oito semanas de treinamento notou-se que a perna ativa na pedalada unipodal apresentou melhoras nas variáveis mensuradas nos grupos TLL, NTLL e algumas no TLD. Também foi encontrada melhora para a perna controle, em algumas variáveis, dos grupos que receberam a terapia LED. Com esse estudo conclui-se que o treinamento unipodal é capaz de melhorar parâmetros como intensidade, ventilação, consumo de oxigênio, eficiência aeróbia, e ainda minimiza os danos musculares induzido pelo exercício no membro que efetuou o treinamento. A terapia LED é capaz de promover as mesmas melhoras em intensidades, consumo de oxigênio e eficiência aeróbia que o treinamento proporcionou, contudo em magnitudes diferentes, ainda é capaz de proporcionar efeito protetor contra lesão muscular induzida pelo exercício. A terapia LED associada ao treinamento potencializa os efeitos conseguidos com cada um isoladamente. / The improvement in physical capacity and/or functional reserve is due to, among other factors, a systematic and organized training program. Aerobic exercise is a frequently used modality in a training program, especially among those who aim to improve physical fitness. However phototherapy has currently gained space in regard to improving the performance of athletes. Based on this information, the purpose of the study was to verify the effect of one-legged cycling, LED therapy and their association on ergospirometric parameters of performance (VO2max, AT and RCT) and on blood concentration of CK. 24 male subjects volunteered for the study and were submitted to a pre-intervention evaluation and an 8-week period of one-legged cycling with LED therapy or placebo. After the intervention period subjects were submitted to a second evaluation. An arrangement containing 50 LEDs and a wavelength of 850 nm was applied during 60 seconds after each training session. Volunteers were divided into the following experimental groups: untrained and LED off (ULOf), untrained and LED on (ULOn), trained and LED off (TLOf) and trained and LED on (TLOn). The leg that received the intervention (training and/or LED therapy) was selected randomly and named active leg (A) and the contralateral limb was named control (C). During the incremental exercise test to volitional failure the ergospirometric variables ventilation (Ve), oxygen uptake (VO2) and oxygen ventilatory equivalent (EqVO2) were measured and blood samples were collected after each stage for lactate and before and 24 hours after the test for the analysis of blood CK. Acute responses from the pre-intervention evaluation showed that the intensity of one-legged cycling led to lower intensity, VO2, Ve, blood lactate and higher increase in blood CK compared to traditional cycling (two-legged). After the 8 weeks of intervention, the active leg showed improvements in the measured variables for the TLOn, ULOn and TLOf groups and, in some of the variables for the groups that received LED therapy. With these data we conclude that one-legged cycling is capable of increasing parameters such as intensity, ventilation, oxygen uptake, aerobic efficiency and minimizes the blood CK responses to exercise in the exercised limb. The association between exercise and Led therapy potentiates the effects achieved with either of the interventions.
94

Čtyřnohý kráčejicí robot / Four legged walking robot

Veleba, Tomáš January 2008 (has links)
The diploma paper deal with control problems of a four legged walking robot. They endeavour to establish and partly implement the walking and control algorithms. They are divided into six parts. Individual chassis types and their advantages and drawbacks are analysed in introduction. Next part describes mechanical design of the robot and also all realised electronics facilities. The third part describes in detail sensors that are used by the robot. Following part deals with description of robot's walking. It explains individual walking phases and analyses both static and dynamic stability. Next part contains description of the robot's software facility. The software facility of the control micro-controller and the algorithm that generates walking are explained in this part. It also describes software facility of control application in computer. Exploration of the possibilities for wireless control is carried out in the last part.
95

Čtyřnohý kráčejicí robot / Four legged walking robot

Fischer, Jan January 2008 (has links)
The object of this thesis is an analysis of the possibilities of a wireless communication and a sensor‘s equipment for a four legged walking robot. The thesis is divided into three parts. In the first part there is a particular sale’s exploration in the section of the wireless communication modules. It refers to the differences among technologies in the methods of signal transmission, the technical parameters but also in the communication protocols. The next part of this thesis is focused on sensor’s equipment with the accent on the possibility of use for a four legged walking robot. It contains a short listing of sensors, which are available in the Czech Republic with division based on the type of sensing magnitude. These two parts make a base for the last part where I have chosen suitable communication modules along with sensors and realization wireless data transfer including control and visualization. The result of this thesis is the complete communication block from the user to the robot.
96

Simulating human-prosthesis interaction and informing robotic prosthesis design using metabolic optimization

Handford, Matthew Lawrence January 2018 (has links)
No description available.
97

Design Optimization for a Compliant,Continuum-Joint, Quadruped Robot

Sherrod, Vallan Gray 01 December 2019 (has links)
Legged robots have the potential to cover terrain not accessible to wheel-based robots and vehicles. This makes them better suited to perform tasks, such as search and rescue, in real-world unstructured environments. Pneumatically-actuated, compliant robots are also more suited than their rigid counterparts to work in real-world unstructured environments with humans where unintentional contact may occur. This thesis seeks to combine the benefits of these two type of robots by implementing design methods to aid in the design choice of a 16 degree of freedom (DoF) compliant, continuum-joint quadruped. This work focuses on the design optimization, especially the definition of design metrics, for this type of robot. The work also includes the construction and closed-loop control of a four-DoF continuum-joint leg used to validate design methods.We define design metrics for legged robot metrics that evaluate their ability to traverse unstructured terrain, carry payloads, find stable footholds, and move in desired directions. These design metrics require a sampling of a legged-robot's complete configuration space. For high-DoF robots, such as the 16-DoF in evaluated in this work, the evaluation of these metrics become intractable with contemporary computing power. Therefore, we present methods that can be used to simplify and approximate these metrics. These approximations have been validated on a simulated four-DoF legged robot where they can tractably be compared against their full counterparts.Using the approximations of the defined metrics, we have performed a multi-objective design optimization to investigate the ten-dimensional design space of a 16-DoF compliant, continuum-joint quadruped. The design variables used include leg link geometry, robot base dimensions, and the leg mount angles. We have used an evolutionary algorithm as our optimization method which converged on a Pareto front of optimal designs. From these set of designs, we are able to identify the trade-offs and design differences between robots that perform well in each of the different design metrics. Because of our approximation of the metrics, we were able to perform this optimization on a supercomputer with 28 cores in less than 40 hours.We have constructed a 1.3 m long continuum-joint leg from one of the resulting quadruped designs of the optimization. We have implemented configuration estimation and control and force control on this leg to evaluate the leg payload capability. Using these controllers, we have conducted an experiment to compare the leg's ability to provide downward force in comparison with its theoretical payload capabilities. We then demonstrated how the torque model used in the calculation of payload capabilities can accurately calculate trends in force output from the leg.
98

Neurobiologically-based Control System for an Adaptively Walking Hexapod

Lewinger, William Anthony 17 March 2011 (has links)
No description available.
99

Local Management and Landscape Effects on the Predator Guild in Vegetable Crops, with a Focus on Long-legged Flies (Diptera: Dolichopodidae)

Kautz, Andrea R. 14 October 2015 (has links)
No description available.
100

Fuzzy Control of Hopping in a Biped Robot

Liu, Yiping 25 August 2010 (has links)
No description available.

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