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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.
851

Komparativní kineziologická analýza záběru při veslování na skifu a při jízdě na trenažeru Concept 2 D PM3. / Comparative - kinsiological analysis of the rowing stroke on a single scull and on a rowing machine Concept 2

Zbořilová, Martina January 2017 (has links)
Title: Kinesiological analysis of the rowing stroke on a single scull and on a rowing ergometer Concept 2 comparison Purposes: The purpose of the present study was to determine a specific structure in timing of selected muscles during two movement patterns - rowing on a single scull and rowing on an ergometer Concept 2. Methods: By surface electromyography we recorded muscular activity, synergies and involvement throughout mean cycle of the rowing stroke. Results: The mutual correlations of mean EMG curves of all measured muscles showed, that there were not found any differences in inter-locomotive synchronization of selected muscles. Established values of correlation (r) showed higher level of dynamic balance (performance similarity between both measured activities. Determination of the muscular activity timing considering onsets and cessations, was in the percentual results explication of the movement cycle inter-locomotive different. Conclusion: Results showed a great similarity in synergies organizing the muscular coordination in between both measured physical activities. But timing of the movement was different in the moments of muscular activity onsets during rowing and during ergometer rowing. This may be attributed to the specificity of on-water locomotion. Key words: Rowing, Concept 2,...
852

Subletální efekty insekticidů neonikotinoidů na migrační potenciál pavouků / Sublethal effects of the insecticides neonicotinoids on migration abilities of spiders

Přibáňová, Gabriela January 2021 (has links)
The purpose for using pesticides is to kill organisms that cause damage (so-called pests) on various crops and thus prevent possible crop losses. Their side effect is a negative impact on non-target organisms. The presented diploma thesis is focused on the effect of neonicotinoids on invertebrates particularly on spiders. Its main goal was to document their influence on behavioral parameters influencing dispersal abilities such as locomotion and tendency to spread by wind (so-called ballooning). The diploma thesis compares the influence of neonicotinoids on model species, Pardosa lugubris (Walckenaer, 1802) and Phylloneta impressa (L. Koch, 1881) with different modes of prey hunting and compares the influence on adult and nymphal stages. Pesticides Actara® 25 WG, Biscaya® 240 OD, Confidor® 200 OD and Mospilan® 20 SP were applied to the spiders under laboratory conditions and their effect was tested at different concentrations and different methods of application. The biggest impact on spiders had Confidor. It clearly had the most significant negative effect on mobility and a tendency to spider wind propagation. The lethal effects were caused by neonicotinoids in nymphal individuals Pardosa lugubris, especially Confidor (even 100% mortality for tarsal application). During an experiment studying the...
853

Comparative Digital Examination of the Talocrural (ankle) Joint Provides Insight into Human bipedal locomotion

Zimmerman, Allison M. 16 August 2013 (has links)
No description available.
854

A First Look: Understanding the Ground Reaction Forces Experienced by Pectoral Fins of Polypterus Senegalus During Terrestrial Locomotion

Bhamra, Gurjit 05 July 2022 (has links)
Polypterus senegalus, an extant member of the ray-finned fishes, can both swim in water and walk overland. Both environments impose different locomotor requirements on Polypterus fins. In an aquatic environment, forward propulsion is largely generated through oscillations of the pectoral fins working in sync with each other. On land, the pectoral fins are engaged in a contralateral gait, and are involved in lifting the body off the ground while simultaneously balancing the body. Polypterus have been shown to undergo behavioural, anatomical, and physiological changes during both short- and long-term exposure to land. Differences in force environments and locomotor behaviour between aquatic and terrestrial environments are hypothesized to be the cause of these plastic changes observed in the musculoskeletal tissues of Polypterus. Despite these observable changes, it is unclear exactly how the pectoral fins are experiencing ground reaction forces (GRF) during terrestrial locomotion. By measuring and quantifying force production during walking in Polypterus, this thesis provides a first look at the relationship between GRFs produced and experienced during walking and the pectoral fins of the amphibious fish, Polypterus. The kinematics of the pectoral fins and fore body were analyzed during terrestrial locomotion, and strategic points across both pectoral fins and body were digitized. Kinematics were compared with GRFs in the thrust (X), stabilizing (Y) and lifting (Z) planes to understand how impact forces travel through the fin tissues. Further analysis, using inverse dynamics, is required to determine how these impact forces travel through the musculature of the pectoral fins, perhaps providing potential hypotheses as to the effects of GRFs and their role in not only how terrestrial locomotion affects the behavioural, anatomical, and physiological plasticity observed in Polypterus, but also the limbs of tetrapods during the evolutionary transition from aquatic to terrestrial environments.
855

Heterozygous Mutant Mice Have a Subtle Locomotor Phenotype

Thiry, Louise, Lemaire, Chloé, Rastqar, Ali, Lemieux, Maxime, Peng, Jimmy, Ferent, Julien, Roussel, Marie, Beaumont, Eric, Fawcett, James P., Brownstone, Robert M., Charron, Frédéric, Bretzner, Frédéric 01 March 2022 (has links)
Axon guidance receptors such as deleted in colorectal cancer (DCC) contribute to the normal formation of neural circuits, and their mutations can be associated with neural defects. In humans, heterozygous mutations in have been linked to congenital mirror movements, which are involuntary movements on one side of the body that mirror voluntary movements of the opposite side. In mice, obvious hopping phenotypes have been reported for bi-allelic mutations, while heterozygous mutants have not been closely examined. We hypothesized that a detailed characterization of heterozygous mice may reveal impaired corticospinal and spinal functions. Anterograde tracing of the motor cortex revealed a normally projecting corticospinal tract, intracortical microstimulation (ICMS) evoked normal contralateral motor responses, and behavioral tests showed normal skilled forelimb coordination. Gait analyses also showed a normal locomotor pattern and rhythm in adult mice during treadmill locomotion, except for a decreased occurrence of out-of-phase walk and an increased duty cycle of the stance phase at slow walking speed. Neonatal isolated spinal cords had normal left-right and flexor-extensor coupling, along with normal locomotor pattern and rhythm, except for an increase in the flexor-related motoneuronal output. Although mice do not exhibit any obvious bilateral impairments like those in humans, they exhibit subtle motor deficits during neonatal and adult locomotion.
856

Hybrid Solutions for Mechatronics. Applications to modeling and controller design.

Bertollo, Riccardo 10 March 2023 (has links)
The task of modeling and controlling the evolution of dynamical sys- tems is one of the main objectives in mechatronics engineering. When approaching the problem of controlling physical or digital systems, the dynamical models have been historically divided into continuous-time, described by differential equations, and discrete-time, described by difference equations. In the last decade, a new class of models, known as hybrid dynamical systems, has gained popularity in the control community because of its high versatility. This framework combines continuous-time and discrete- time evolution, thus allowing for both the description of a broader class of systems and the achievement of better-performing controllers, compared to the traditional continuous-time alternatives. After the first rigorous introduction of the framework, several Lyapunov-based results were published in the literature, and numerous application areas were shown to benefit from the introduction of a hybrid dynamics, like systems involving impacts or physical systems connected to digital controllers (cyber-physical systems). In this thesis, we use the hybrid framework to study different mechatronics-inspired control problems. The applications we consider are diverse, so we split the presentation into three parts. In the first part we further analyze a particular hybrid control strategy, known as reset control, providing some new theoretical guarantees, together with an application to adaptive control. In the second part we consider two applications of the hybrid framework to the network dynamics field, specifically we analyze the problems of distributed state estimation and of uniform synchronization of nonlinear oscillators. In the third part, we use a hybrid approach to study two applications where this framework has been rarely employed, or not at all, namely smart agriculture and trajectory tracking for a bipedal walking robot. We study these application-inspired problems from a theoretical point of view, giving robust Lyapunov-based stability guarantees. We complement the theoretical analysis with numerical results, obtained from simulations or from experiments.
857

MULTI-USER REDIRECTED WALKING AND RESETTING UTILIZING ARTIFICIAL POTENTIAL FIELDS

Hoffbauer, Cole 09 July 2018 (has links)
No description available.
858

The Nematalycidae (Acariformes): An exploration of large-scale morphological variation and evolution using low-temperature scanning electron microscopy

Bolton, Samuel John 14 September 2016 (has links)
No description available.
859

The biodynamics of arboreal locomotion in the gray short-tailed opossum ( <em>Monodelphis domestica</em> )

Lammers, Andrew R. 18 December 2004 (has links)
No description available.
860

Stable Control of Jumping in a Planar Biped Robot

Hester, Matthew S. 15 July 2009 (has links)
No description available.

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