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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

Unsteady heat transfer simulation for a diesel engine

Shamah, Eliahu, January 1968 (has links)
Thesis (M.S.)--University of Wisconsin--Madison, 1968. / eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references.
2

Outlook in Infants With Univentricle Anatomy Using Oral Motor Stimulation

Thomas, Brittany L., Glenn, L. Lee 01 November 2013 (has links)
Excerpt: The conclusion statements by Coker-Bolt, P., Jarrad, C., Woodard, F., & Merrill, P. (2012). The effects of oral motor stimulation on feeding behaviors of infants born with univentricle anatomy. Journal of Pediatric Nursing, 28(1), 64–71. doi: https://doi.org/10.1016/j.pedn.2012.03.024 were interesting, but the support for the conclusions was absent because of a number of shortcomings. The first shortcoming is that the effect of oral motor stimulation on gastric tube use, ENT abnormalities, or barium swallowing test was weak or absent. The second shortcoming was the shorter hospital stays of the infants in the study could be explained by other factors. These weaknesses would prevent the immediate adoption of those conclusions in health care as of now.
3

Řízení BLDC motoru pomocí LabView FPGA / BLDC motor control using LabView FPGA

Ruhás, Sándor January 2018 (has links)
This thesis focuses on BLDC motor control algorithms with model based design approach. Models and control algorithms were programmed in LabView, the NI MyRIO was used as a hardware platform. For hall-sensor feedback controlled application an already finished power inverter was used from a Honeywell rotary actuator. For sensor-less motor control an indirect sensing of BEMF signal is applied using motor phase current measurement. The time-critical parts of the algorithms are programmed for FPGA, the non-time-critical parts are programmed for LabView Real-Time module.
4

Action-sentence compatibility: the role of action effects and timing

Diefenbach, Christiane, Rieger, Martina, Massen, Cristina, Prinz, Wolfgang 29 July 2022 (has links)
Research on embodied approaches to language comprehension suggests that we understand linguistic descriptions of actions by mentally simulating these actions. Evidence is provided by the action-sentence compatibility effect (ACE) which shows that sensibility judgments for sentences are faster when the direction of the described action matches the response direction. In two experiments, we investigated whether the ACE relies on actions or on intended action effects. Participants gave sensibility judgments of auditorily presented sentences by producing an action effect on a screen at a location near the body or far from the body. These action effects were achieved by pressing a response button that was located in either the same spatial direction as the action effect, or in the opposite direction. We used a go/no-go task in which the direction of the to-be-produced action effect was either cued at the onset of each sentence (Experiment 1) or at different points in time before and after sentence onset (Experiment 2). Overall, results showed a relationship between the direction of the described action and the direction of the action effect. Furthermore, Experiment 2 indicated that depending on the timing between cue presentation and sentence onset, participants responded either faster when the direction of the described action matched the direction of the action effect (positive ACE), or slower (negative ACE). These results provide evidence that the comprehension of action sentences involves the activation of representations of action effects. Concurrently activated representations in sentence comprehension and action planning can lead to both priming and interference, which is discussed in the context of the theory of event coding.
5

Program pro výpočet EC motorů / Program for calculation of BLDC motor

Chloupek, Karel January 2009 (has links)
This thesis focuses on problematics of BLDC motors. Thesis consist of theoretical and practical part. In introduction is the reader acquaint with problematics, principals of development, advantages and disadvantades of BLDC motors. Then folows a description of different types, their realization and construction. Main part of this thesis deals with segment stator. For this type of magnetic circuit was developed computing software. This software will design and provide calculation of motor due to given parameters. In second step, the program generates source code for FEMM software, which provides a simulation. This is the most effective way, how can designer simply verify his calculations
6

Influence de l'environnement odorant sur le processus de simulation motrice révélée par une cellule de force en population jeune et vieillissante saine / Influence of odorant environment on motor simulation process revealed by a grip-force sensor in young and healthy aging population

Blampain, Justine 03 April 2019 (has links)
L’avancée de l’âge entraîne une diminution du contrôle moteur ainsi que l’apparition de troubles de la marche et de l'équilibre. Ces difficultés affectent la capacité des personnes âgées à accomplir les activités de la vie quotidienne et à maintenir leur indépendance (Salthouse, 2000 ; Seidler et al., 2010). Dans le cadre des théories de la simulation, de nombreuses études ont révélé des similitudes, tant au niveau comportemental que neuronal, entre exécution et simulation motrice (Decety & Jeannerod, 1995 ; Grezes & Decety, 2001). Selon Jeannerod (2001), ce processus cognitif permet de simuler mentalement une action, tandis qu’un mécanisme d’inhibition est mis en place pour contrôler toute exécution motrice externe (Bonnet et al., 1997 ; Jeannerod, 1994). Il est toutefois difficile de caractériser ce processus et d’ainsi révéler les troubles de simulation. Par ailleurs, peu d’études se sont intéressées à stimuler le processus de simulation motrice, notamment par l’utilisation de stimuli odorants. En effet, il a été rapporté que les odeurs avaient de nombreux effets sur la cognition (Millot et al., 2002), les émotions (Matsunaga et al., 2012), mais également l’exécution motrice (Castiello et al., 2006). Ce travail de thèse vise à évaluer l’effet de l’environnement odorant sur la simulation motrice lors de tâches d’observation et d’imagerie d’actions motrices chez des participants jeunes et âgés sains. Dans une première partie, nous avons révélé la simulation motrice à l’aide d’une cellule de force, lors de l’observation d’actions. Une amplitude plus importante des variations de la force de préhension a été observée lors du visionnage de scènes vidéo d’actions chez des sujets jeunes (étude 1), reflet de la mise en place du processus de simulation motrice. Ces résultats ont été retrouvés lors de la présentation de photos représentant des activités de faible (marche) ou forte (course) intensité (étude 2). Dans une deuxième partie, nous nous sommes intéressés à l’effet des odeurs sur le processus de simulation motrice, la cognition et les émotions. En effet, les odeurs sont fortement liées à la mémoire, qu’elle soit émotionnelle (souvenirs) ou sémantique (catégorisation d’une odeur). Placés dans un environnement odorant, les participants ressentaient une sensation de bien-être lorsque les odeurs rappelaient des souvenirs autobiographiques (étude 3). En nous basant sur le modèle d’Act-in (Versace et al.,2014), sentir une odeur entrainerait une réactivation des traces en mémoire et permettrait de se représenter les caractéristiques perceptuelles d’un objet. Ainsi, sentir une orange (gros fruit) ou une fraise (petit fruit) impliquerait une simulation et une exécution motrice différente en fonction de leurs caractéristiques propres. Nous avons ainsi évalué l’influence des odeurs de fraise et d’orange sur la simulation d’actions impliquant la manipulation de fruits (Etude 4). Il était observé un relâchement de la contraction musculaire lorsqu’une odeur de fraise était présentée. L’odeur d’orange entrainait en revanche une plus importante contraction musculaire, et cela même si les participants devaient s’imaginer manipuler une fraise. Ces études ouvrent la question de la représentation perceptuelle évoquée par l’odeur et pouvant influencer la simulation et donc l’exécution. Utiliser des odeurs pourrait, dès lors, être utile lors la prise en soin des personnes ayant des troubles de la motricité en augmentant la sensation de bien-être ressenti et en stimulant le processus de simulation motrice par l’évocation des caractéristiques de perception par l’odeur. Un ensemble de perspectives de recherches et d’applications cliniques s’ouvrent au regard de ces résultats, et seront discutées dans cette thèse. / With advanced age, a decline in fine motor control, gait and balance is observed. These difficulties affect the elderly’s ability to perform daily activities and maintain their independence (Salthouse, 2000; Seidler et al., 2010). In the context of simulation theories, numerous studies revealed similarities between motor execution and simulation, both at a behavioral and a neural level, in neuronal behavioral behavior (Decety and Jeannerod 1995, Grezes and Decety 2001). According to Jeannerod (2001), this cognitive process permits to simulate an action, while a mechanism of inhibition operates to control any external motor execution (Bonnet et al., 1997, Jeannerod, 1994). However, it is difficult to characterize this process and thus reveal the simulation disorders. In addition, few studies were interesting in the stimulation of the motor simulation process, especially by using odorant stimuli. Indeed, odors can have effects on cognition (Millot et al., 2002), emotions (Matsunaga et al., 2012), and motor execution (Castiello et al., 2006). This thesis aims to evaluate the effect of the odorant environment on motor simulation during action observation and motor imagery task in healthy young and elderly participants. In the first part, we revealed the motor simulation by using a grip-force sensor during action observation and motor imagery tasks. A higher amplitude of the grip force variations was observed in young participants when they were watching video scenes of actions (study 1), reflecting the involving of motor simulation process. These results were also found when pictures depicting either a low (walk) or high (race) intensity of force were presented to young participants (study 2). In the same way, these variations were observed in elderly participants when they were watching video of reach-to-grasp actions (study 3). In the second part, we were interested in the effect of odors on the motor simulation process, cognition and emotions. Indeed, odors are strongly related to memory, either in an emotional (memories) or in a semantic (categorization of an odor) way. Placed in an odorant environment, participants felt more positive affects when the odors recalling autobiographical memories were diffused (Study 4). Based on the Act-in model (Versace et al., 2014), perceiving an odor would lead to a reactivation of memory traces implying the perceptual characteristics of this odor. Thus, smelling an orange (large fruit) or a strawberry (small fruit) would lead to a different motor simulation and execution according to their own characteristics. We thus evaluated the influence of strawberry and orange odors on the simulation of reaching-grasping actions involving fruit handling (Study 4). A size-congruence effect was found when a strawberry odor was diffused, as revealed with the muscular release observed. On the other hand, the orange odor led to a more important muscular contraction, especially when the participants had to imagine handle a strawberry. These studies open the question of the perceptual representation evoked by the odors that can influence the simulation process and thus the execution. Using odors could be relevant in clinical settings for people who are suffering from motor disorders by improving the well-being feeling and also stimulate the motor simulation process by evoking perceptual characteristics with the odors. A set of research perspectives and clinical applications will be opened considering these results and will be discussed in this thesis.
7

Feasibility of an Electric Jetpack

Youard, Timothy John January 2010 (has links)
The Martin Aircraft Company Limited has been developing the Martin Jetpack for over 25 years. The recent worldwide launch of the Jetpack has enabled the company to step up its research and development programme. The goal of this project was to determine the feasibility of an electrically powered version of the Martin Jetpack. The feasibility of the Electric Jetpack was determined by researching energy storage technologies, researching power cable technologies, simulations of flight times, surveys of electric motors, and the development of a simulation program which was used to optimise some preliminary custom motor designs. The overall conclusion of this project was that the Electric Jetpack was feasible only when it was powered through a tethered power cable, and on-board energy storage was not used. An investigation into current energy storage technologies showed that the Electric Jetpack is not considered feasible when using on-board energy storage, however it is possible to obtain flight for a very short time. The energy storage technologies studied were batteries, fuel cells, and ultra-capacitors. It was found that the best performing technology was the lithium iron nano-phosphate battery. A simulation of flight time showed that this battery type would be able to provide flight for approximately 3.6 minutes. Future trends indicated that the Electric Jetpack with on-board energy storage may eventually be feasible when using a lithium-ion based battery due to improvements being made in energy density and power density. By using a tethered power cable, the weight of the on-board energy storage could be eliminated. This was shown to be a feasible method for powering the Electric Jetpack for applications where the Jetpack needs to only be operated in a small area. The best cable type to use was a multi-stranded flexible cable operating at a high DC bus voltage. The weight of a 5 meter power cable using a 1000 V bus voltage was shown to be 4.9 kg. Potential applications for this kind of Jetpack could include thrill rides and rescue operations from multi-storied buildings. A cable made from carbon nanotubes was shown to be a future technology that could offer a lighter cable. A survey of currently available electric motors showed that none met both the power density and speed required by the Electric Jetpack, even when using a tethered power cable to eliminate the energy storage weight. Because of this, a custom motor design was needed. Research into motor technologies showed that the permanent magnet brushless DC (PMBLDC) motor was the most suited type for the Electric Jetpack. The permanent magnet brushless AC (PMBLAC) motor was also suitable. A PMBLDC motor simulation program was developed using MATLAB which could be used to optimise preliminary custom designs. A characterisation of allowable motor time constants for the PMBLDC motor type was made in order to speed up the simulation time. The optimisation results showed that a power density of 5.41 kW/kg was achievable for the motor when it was located inside the ducted fan tubes, and a power density of 6.56 kW/kg was achievable when the motor was located outside the ducted fans and operated at a higher speed. The motor designs were shown to be within the expected torque per unit rotor volume (TRV) range for aerospace machines. The best power density figures would leave between 37 kg and 42 kg of weight for the motor driver/controller, cable weight, and miscellaneous motor parts. This was considered to be feasible. An FEM simulation was made on one of the optimised motor designs. The FEM results agreed with the parametric results within reasonable accuracy. The parametric back-EMF waveform over-estimated the effects of slotting.

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