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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

Artificial pattern recognition with indeterminate input : a methodological review, and an original design for an adaptive system having prospective application in the real-time monitoring of biosignals such as ECG

Parmakis, Gerry January 1999 (has links)
No description available.
2

Measurement and data analysis techniques for the investigation of adult cerebral haemodynamics using near infrared spectroscopy

Elwell, Clare Elizabeth January 1995 (has links)
No description available.
3

Empirical Studies of Arundinaria Species for Restoration Purposes

Mills, Mary Catherine 30 April 2011 (has links)
The research in this thesis concentrates on investigation of the ecology of Arundinaria species for restoration purposes. Arundinaria species are key components in the canebrake ecosystem that was once prominent in the southeastern United States. Arundinaria still occurs as an understory component of bottomland hardwood forests, but with intense agricultural development and urbanization over the past 200 years, canebrakes are now a critically endangered ecosystem with greater than 98% loss. Specifically the thesis addresses the establishment of Arundinaria with other plant species and site preparation techniques. This study indicated that A. gigantea planted into plots dominated by non-native plants benefited significantly more from site preparation (soil tillage, herbicide application) than cane planted into native-species-dominated assemblages. The last portion of the research examined effects of inundation on A. gigantea and A. tecta. Arundinaria tecta appeared to be more flood tolerant than A. gigantea, reflecting habitats in which these species are known to occur.
4

Model Based Enhancement of Bioimpedance Spectroscopy Analysis : Towards Textile Enabled Applications

Buendía López, Rubén January 2011 (has links)
Several signal processing approaches have been developed to overcome the effect of stray capacitances in Electrical Bioimpedance Spectroscopy (EBIS) measurements. EBIS measurements obtained with textile-enabled instrumentation are more vulnerable to stray capacitances. Currently, the most widespread approach for correcting the effect of stray capacitances in EBIS is the time delay ( Td) compensation method, which also has several drawbacks. In this study, the Td method is revisited and its limitations and its lack of a scientific basis are demonstrated. To determine better ways to overcome the effect of stray capacitances, a simplified measurement model is proposed that is based on previous models of artefacts in EBIS measurements described in the literature. The model consists of a current divider with a parasitic capacitance (Cpar) in parallel with the load. Cpar creates a pathway for the measurement current to leak away from the load, provoking a capacitive leakage effect. In this thesis, three approaches with different limitations are proposed to overcome the capacitive leakage effect. The first approach estimates Cpar and subtracts it from the measurements, thus finding the load. Cpar can be estimated because the susceptance of biological tissue is null at infinite frequency. Therefore, at high frequencies, the susceptance of the tissue can be neglected, and the slope of the susceptance of the measurement is Cpar. The accuracy of Cpar depends on the maximum frequency measured and the value of Cpar. Therefore, it may not be possible to accurately estimate small values of Cpar in the typical frequency ranges used in EBIS. The second and third approaches use the Cole fitting process to estimate the Cole parameters, which form the basis for most EBIS applications. Because the conductance of the measurement is free from the effect of Cpar, performing Cole fitting on the conductance avoids the effect of Cpar in the fitting process. With a poor skin-electrode contact, this approach may not be sufficiently accurate. The third approach would be to perform the Cole fitting on the modulus with a reduced upper frequency limit because the modulus and the low-medium frequencies are very robust against the effect of artefacts. In this approach, a slight capacitive leakage effect is unavoidable. Since it is common to find tainted measurements, especially among those obtained with textile-enabled instrumentation, it is important to find viable methods to avoid their effect. The three methods studied showed that they could reduce the effect of tainted measurements. / QC 20120313
5

The physiological effects of pseudoephedrine on endurance cycling : a thesis submitted in the partial fulfilment of the requirements for the degree of Master of Science in Sport and Exercise Science, Massey University (Palmerston North, New Zealand)

Mouatt, Joshua Roger January 2008 (has links)
Background: Pseudoephedrine (PSE) is a mild central nervous system stimulant that when consumed at a high dosage has the potential to alter physiological and psychophysical responses. PSE is widely accessible as over-the-counter medication and despite limited research into PSE at high dosages or its effects on prolonged exercise (>2 hours) is no-longer on the World Anti-Doping Association’s banned substance list. Currently unrestricted in sport and with no real understanding of the abovementioned responses during endurance exercise there is a high potential for abuse in sport. A recent study performed in our laboratory found PSE to improve self-paced cycling performance in some individuals, however no physiological measurements were taken Purpose: The primary purpose of this study was to determine the physiological effects of PSE at a dosage previously shown to improve performance (2.5 mg/kg) in some individuals during prolonged cycling. A secondary purpose of this study was to assess the effect on endurance cycling performance. Methods: In a randomized, double-blind and counter-balanced design, ten welltrained cyclists participated in two trials, consisting of 120 min of fixed-intensity cycling at 65% VO2max followed by a set work, self-paced time-trial (TT) of ~30 min, following ingestion of either 2.5 mg/kg PSE or visual-matched glucose placebo. Venous blood samples were collected before and during exercise, along with body temperatures and heart rate. Perceived effort and expired gas samples were collected during exercise. Exercise and diet was controlled ~48-hours prior to the trials. Results: Mean heart rate was significantly higher with PSE (P = 0.028) during fixed-intensity exercise. Blood glucose concentrations were significantly lower with PSE (P <0.001) for the first 40 min of fixed-intensity exercise. Respiratory exchange ratio was lower in the final 20-min of fixed-intensity and TT with PSE. Blood lactate, perceived effort, ventilation, and body temperatures were not significantly different between conditions during exercise, nor was TT performance; however individual response was variable. Conclusions: PSE ingestion increased heart rate during endurance cycling and initially suppressed carbohydrate release into the bloodstream while increasing fat oxidation in the later stages of exercise. Despite individual responses, endurance cycling performance remained unchanged with PSE ingestion.
6

Performance, physiological, and perceptual effects of wearing graduated compression stockings during running : a thesis presented in partial fulfilment of the requirements for a degree of Master of Science in Sport and Exercise Science at Massey University, Auckland, New Zealand

Creasy, Robert January 2008 (has links)
Purpose: The aims of these studies were to examine the effects of wearing different grades of graduated compression stockings (GCS) on performance, physiological, and perceptual measures before, during, and after exercise in well-trained runners. Method: Two separate running studies were conducted where participants wore different grades of GCS compared with a placebo control stocking in random, counter-balanced order: (1) a field study focussed on a series of 10-km running performances on a 400m track; (2) a laboratory study that examined the effects of 40-min treadmill running on physiological, perceptual, and muscle function responses. Changes in muscle function and damage were determined pre- and post-run by measuring creatine kinase (CK) and myoglobin (Mb) concentrations, counter-movement jump (CMJ) height, muscle soreness, and pressure sensitivity. Physiological measurements of heart rate (HR), oxygen uptake (V&O2), blood lactate concentration [La], and ratings of perceived exertion (RPE) were measured during running. Pre- and post-run perceptual scales assessed comfort, tightness and pain associated with wearing GCS. Results: There were no significant differences in 10-km run time, mean HR, V&O2, [La], and RPE for participants wearing different GCS in (1) and (2) (P<0.05). Con and Low were rated most comfortable (P<0.05) and Hi were tightest (P<0.05) and induced more pain (P<0.05) when GCS were compared in both studies. CMJ was better in participants wearing Low and Med GCS post-run compared with Con in (1) and for Con and all GCS at 0 h post-exercise in (2). CK and Mb levels were higher (P<0.05) and pressure sensitivity was more pronounced (P<0.05) at 0 h post-run for Con and all GCS (2). Few participants (4/10) reported muscle soreness at any one location in (2). Conclusions: Well-trained runners did not experience improved performance, physiological, or perceptual responses when wearing different grades of GCS during 10- km track or 40 min treadmill running compared with a control garment. 40 min treadmill running at 80% V&O2 max may not be strenuous enough to elicit a loss of muscle function in well-trained runners. Runners felt more comfortable wearing GCS that had less compression.
7

The physiological effects of pseudoephedrine on endurance cycling : a thesis submitted in the partial fulfilment of the requirements for the degree of Master of Science in Sport and Exercise Science, Massey University (Palmerston North, New Zealand)

Mouatt, Joshua Roger January 2008 (has links)
Background: Pseudoephedrine (PSE) is a mild central nervous system stimulant that when consumed at a high dosage has the potential to alter physiological and psychophysical responses. PSE is widely accessible as over-the-counter medication and despite limited research into PSE at high dosages or its effects on prolonged exercise (>2 hours) is no-longer on the World Anti-Doping Association’s banned substance list. Currently unrestricted in sport and with no real understanding of the abovementioned responses during endurance exercise there is a high potential for abuse in sport. A recent study performed in our laboratory found PSE to improve self-paced cycling performance in some individuals, however no physiological measurements were taken Purpose: The primary purpose of this study was to determine the physiological effects of PSE at a dosage previously shown to improve performance (2.5 mg/kg) in some individuals during prolonged cycling. A secondary purpose of this study was to assess the effect on endurance cycling performance. Methods: In a randomized, double-blind and counter-balanced design, ten welltrained cyclists participated in two trials, consisting of 120 min of fixed-intensity cycling at 65% VO2max followed by a set work, self-paced time-trial (TT) of ~30 min, following ingestion of either 2.5 mg/kg PSE or visual-matched glucose placebo. Venous blood samples were collected before and during exercise, along with body temperatures and heart rate. Perceived effort and expired gas samples were collected during exercise. Exercise and diet was controlled ~48-hours prior to the trials. Results: Mean heart rate was significantly higher with PSE (P = 0.028) during fixed-intensity exercise. Blood glucose concentrations were significantly lower with PSE (P <0.001) for the first 40 min of fixed-intensity exercise. Respiratory exchange ratio was lower in the final 20-min of fixed-intensity and TT with PSE. Blood lactate, perceived effort, ventilation, and body temperatures were not significantly different between conditions during exercise, nor was TT performance; however individual response was variable. Conclusions: PSE ingestion increased heart rate during endurance cycling and initially suppressed carbohydrate release into the bloodstream while increasing fat oxidation in the later stages of exercise. Despite individual responses, endurance cycling performance remained unchanged with PSE ingestion.
8

The physiological effects of pseudoephedrine on endurance cycling : a thesis submitted in the partial fulfilment of the requirements for the degree of Master of Science in Sport and Exercise Science, Massey University (Palmerston North, New Zealand)

Mouatt, Joshua Roger January 2008 (has links)
Background: Pseudoephedrine (PSE) is a mild central nervous system stimulant that when consumed at a high dosage has the potential to alter physiological and psychophysical responses. PSE is widely accessible as over-the-counter medication and despite limited research into PSE at high dosages or its effects on prolonged exercise (>2 hours) is no-longer on the World Anti-Doping Association’s banned substance list. Currently unrestricted in sport and with no real understanding of the abovementioned responses during endurance exercise there is a high potential for abuse in sport. A recent study performed in our laboratory found PSE to improve self-paced cycling performance in some individuals, however no physiological measurements were taken Purpose: The primary purpose of this study was to determine the physiological effects of PSE at a dosage previously shown to improve performance (2.5 mg/kg) in some individuals during prolonged cycling. A secondary purpose of this study was to assess the effect on endurance cycling performance. Methods: In a randomized, double-blind and counter-balanced design, ten welltrained cyclists participated in two trials, consisting of 120 min of fixed-intensity cycling at 65% VO2max followed by a set work, self-paced time-trial (TT) of ~30 min, following ingestion of either 2.5 mg/kg PSE or visual-matched glucose placebo. Venous blood samples were collected before and during exercise, along with body temperatures and heart rate. Perceived effort and expired gas samples were collected during exercise. Exercise and diet was controlled ~48-hours prior to the trials. Results: Mean heart rate was significantly higher with PSE (P = 0.028) during fixed-intensity exercise. Blood glucose concentrations were significantly lower with PSE (P <0.001) for the first 40 min of fixed-intensity exercise. Respiratory exchange ratio was lower in the final 20-min of fixed-intensity and TT with PSE. Blood lactate, perceived effort, ventilation, and body temperatures were not significantly different between conditions during exercise, nor was TT performance; however individual response was variable. Conclusions: PSE ingestion increased heart rate during endurance cycling and initially suppressed carbohydrate release into the bloodstream while increasing fat oxidation in the later stages of exercise. Despite individual responses, endurance cycling performance remained unchanged with PSE ingestion.
9

Tecnologías Inmersivas y medidas psicofisiológicas para la evaluación y entrenamiento de niños con Trastorno del Espectro Autista

Olmos Raya, Elena 03 May 2021 (has links)
[ES] El Trastorno del Espectro Autista (TEA) es una afección compleja que se encuentra dentro de los llamados Trastornos del Neurodesarrollo. Está caracterizada por la presencia de disfunciones en las interacciones sociales, en la capacidad comunicativa, pensamiento simbólico, así como, conductas estereotipadas y desregulación de carácter sensorial. Actualmente, dada su elevada prevalencia, ha despertado el interés científico para poder llevar a cabo diagnósticos más tempranos que repercutan en intervenciones más eficaces. Hasta el momento el diagnóstico del TEA se ha venido realizando mediante baterías diagnósticas estandarizadas basadas en criterios cualitativos, por lo cual, la respuesta puede distar de la obtenida en un contexto real. Es por ello que herramientas como la Realidad Virtual (RV), con la potencialidad de reproducir entornos con elevado grado de realismo, pueden ser un contexto válido tanto para la evaluación como para la intervención terapéutica. Se han aplicado entornos virtuales no inmersivos, dado el rechazo de la población TEA a utilizar visores RV, aunque con resultados observacionales. Dichas limitaciones pueden superarse con el uso de los llamados Entornos Virtuales Inmersivos (EVI), ya que suponen una solución tecnológica no invasiva, con mayor capacidad de inmersión y, por tanto, de generar respuestas con mayor similitud a las obtenidas en un contexto real. Las mediciones de carácter observacional pueden superarse con mediciones fisiológicas, tales como, la actividad electrodermal (EDA), que proporciona la respuesta de la excitación corporal en forma de sudoración ante un estímulo o el eye tracking, el cual muestra el comportamiento ocular. Ambas suponen respuestas implícitas, inconscientes y cuantificables, que pueden ayudar a definir la afección. Por todo ello, la presente Tesis Doctoral, compuesta de tres estudios, tiene como objetivo unir el uso de EVI, con capacidad de estimulación visual, auditiva y olfativa con medidas fisiológicas, focalizadas en la evaluación y entrenamiento del TEA, además de estudiar las relaciones entre las mismas y las baterías diagnósticas del TEA. El Estudio nº 1 valoró la adaptación de los participantes a los dispositivos y el EVI y los niveles EDA en un contexto de respuesta al saludo. Los resultados hallaron que los sujetos TEA mostraron una tolerancia similar en el uso del EVI y del dispositivo EDA. Aumentaron sus niveles de excitación con respecto al estado de reposo previo (Ratio), cuando intervino el sentido del olfato, no habiendo relaciones significativas con las baterías diagnósticas. El Estudio nº 2 profundizó en los niveles EDA en un contexto de imitación total o parcial. Los resultados mostraros que los sujetos TEA mostraron una menor activación (Ratio), ante procesos de imitación total, con estimulación olfativa, no encontrando relaciones significativas con las baterías diagnósticas. El Estudio nº 3 estudió el EDA y el comportamiento ocular en un EVI basado en un Centro Comercial. Los resultados EDA, no proporcionaron diferencias en la sesión de evaluación, pero descendieron en los sujetos TEA tras una sesión de entrenamiento. El comportamiento ocular en la sesión de evaluación discriminó entre los grupos, pero en el entrenamiento el comportamiento fue similar. Las relaciones entre dichas medidas y las baterías diagnósticas no mostraron relaciones significativas. Tecnologías inmersivas y medidas psicofisiológicas para la evaluación y entrenamiento de niños con Trastorno del Espectro Autista Como conclusión final cabe señalar que, la medida electrodermal que contó con mayor capacidad para identificar a la población TEA fue la medida Ratio. Mientras que el EDA, tras el entrenamiento, fue indicador de una mejora de la excitación ante situaciones de señalado, respuesta al nombre y atención conjunta, en el caso del comportamiento ocular, fue capaz de diferenciar entre los grupos únicamente en la / [CA] El Trastorn de l'Espectre Autista (TEA) és una afecció complexa que es troba dins dels anomenats Trastorns del Neurodesenvolupament. Està caracteritzada per la presència de disfuncions en les interaccions socials, en la capacitat comunicativa, pensament simbòlic, així com, conductes estereotipades i desregulació del caràcter sensorial. Actualment, donada la seua elevada prevalença, ha despertat l'interés científic per poder dur a terme diagnòstics més primerencs que deriven en intervencions més eficaces. Fins al moment el diagnòstic del TEA s'ha realitzat mitjançant bateries diagnòstiques estandarditzades basades en criteris qualitatius, és per això que la resposta pot ser diferent a l'obtinguda en un context real. Per tant, eines com la Realitat Virtual, amb la capacitat de reproduir entorns amb un elevat grau de realisme, poden ser un context vàlid tant per a l'avaluació com per a la intervenció terapèutica. S'han aplicat entorns virtuals no immersius, donat el rebuig de la població TEA a utilitzar visors RV, malgrat que amb resultats observacionals. Dites limitacions poden superar-se amb l'ús dels anomenats Entorns Virtuals Immersius (EVI), ja que suposen una solució tecnològica no invasiva, amb major capacitat d'immersió i per tant, de generar respostes amb major similitud a les obtingudes en un context real. Les mesures de caràcter observacional poden superar-se amb mesures fisiològiques, tals com, l'activitat electrodermal (EDA), que proporciona la resposta de l'excitació corporal en forma de sudoració enfront d'un estímul o l'eye tracking, el qual mostra el comportament ocular. Ambdues suposen respostes implícites, inconscients i quantificables, que poden ajudar a definir l'afecció. Per tot això, la present Tesi Doctoral, composta de tres estudis, té com a objectiu unir l'ús d'EVI, amb capacitat d'estimulació visual, auditiva i olfactiva amb mesures fisiològiques, focalitzades en l'avaluació i entrenament del TEA, a més d'estudiar les relacions entre les mateixes i les bateries diagnòstiques del TEA. L'Estudi nº 1 va valorar l'adaptació dels participants als dispositius i l'EVI i els nivells EDA en un context de resposta salutació. Els resultats van trobar que els subjectes TEA van mostrar una tolerància similar en l'ús d'EVI i del dispositiu EDA. Van augmentar els seus nivells d'excitació pel que fa a l'estat de repòs prEVI (Ràtio), quan va intervenir el sentit de l'olfacte, no havent-hi relacions significatives amb les bateries diagnòstiques. L'Estudi nº 2 va aprofundir en els nivells EDA en un context d'imitació total o parcial. Els resultats mostraren que els subjectes TEA mostraren una menor activació (Ràtio), davant de processos d'imitació total, amb estimulació olfactiva, no trobant relacions significatives amb les bateries diagnòstiques. L'Estudi nº 3 va estudiar l'EDA i el comportament ocular a un EVI basat en un Centre Comercial. Els resultats EDA, no van proporcionar diferències en la sessió d'avaluació, però van baixar en els subjectes TEA després d'una sessió d'entrenament. El comportament ocular en la sessió d'avaluació va discriminar entre els grups, però en l'entrenament el comportament va ser similar. Les relacions entre aquestes mesures i les bateries diagnòstiques no van mostrar relacions significatives. Com a conclusió final es pot assenyalar que, la mesura electrodermal que va comptar amb major capacitat per a identificar a la població TEA fou la mesura Ràtio. Pel quefa a l'EDA, després de l'entrenament, va ser un indicador d'una millora de l'excitació enfront de situacions d'assenyalament, resposta al nom i atenció conjunta, en el cas del comportament ocular, va ser capaç de diferenciar entre els grups únicament en la sessió d'avaluació. Finalment, l'EDA i el comportament ocular, no van ser mesures amb capacitat correlacional amb les bateries diagnòstiques. / [EN] Autism Spectrum Disorder (ASD) is a complex condition that falls under the category of so-called Neurodevelopmental Disorders. It is characterized by the presence of dysfunctions in social interactions, in the communicative capacity, symbolic thinking, as well as, stereotypical behaviours and deregulation of sensorial character. Currently, given its high prevalence, it has awakened scientific interest in order to carry out earlier diagnoses that will have an impact on more effective interventions. Until now, the diagnosis of ASD has been carried out by means of standardized diagnostic batteries based on qualitative criteria, so that the response may be far from that obtained in a real context. Therefore, tools such as Virtual Reality (VR), with the potential to reproduce highly realistic environments, can be a valid context for both assessment and therapeutic intervention. Non-immersive virtual environments have been applied, given the refusal of the ASD population to use VR viewers, although with bservational results. These limitations can be overcome with the use of so-called Immersive Virtual Environments (IVEs), since they represent a non-invasive technological solution, with a greater capacity for immersion and, therefore, for generating responses that are more similar to those obtained in a real context. Observational measurements can be overcome with physiological measurements, such as electrodermal activity (EDA), which provides the body's response in the form of sweating to a stimulus, or eye tracking, which shows the behaviour of the eye. Both involve implicit, unconscious and quantifiable responses, which can help define the condition. Consequently, the present Doctoral Thesis, composed of three studies, aims to unite the use of IVE, with the capacity of visual, auditory and olfactory stimulation with physiological measures, focused on the evaluation and training of ASD, as well as studying the relationships between them and the diagnostic batteries of ASD. The Study nº1 evaluated the adaptation of the participants to the deviIces and the IVE and the EDA levels in a context of response to the greeting. The results found that ASD subjects showed similar tolerance in the use of the IVE and EDA dEVIce. They increased their levels of arousal with respect to the prEVIous resting state (Ratio), when the sense of smell was involved, with no significant relationship with the diagnostic batteries. Study nº2 studied in depth the EDA levels in a context of total or partial imitation. The results show that the ASD subjects showed a lower activation (Ratio), when facing total imitation processes, with olfactory stimulation, finding no significant relations with the diagnostic batteries. The Study nº3 studied the EDA and the ocular behaviour in an IVE based in a Shopping Centre. The EDA results, did not provide differences in the evaluation session, but they decreased in the ASD subjects after a training session. Eye behaviour in the assessment session discriminated between the groups, but in the training the behaviour was similar. The relationships between these measures and the diagnostic batteries did not show significant relationships. As a final conclusion, it should be pointed out that the electrodermal measure that had more capacity to identify the ASD population was the Ratio measure. While the EDA, after the training, was an indicator of an improvement of the excitement in front of situations of signalling, response to the name and joint attention, in the case of the ocular behaviour, it was one able to differentiate between the groups only in the evaluation session. Finally, the EDA and the ocular behaviour, were not measured with correlational capacity with the diagnostic batteries. / Olmos Raya, E. (2021). Tecnologías Inmersivas y medidas psicofisiológicas para la evaluación y entrenamiento de niños con Trastorno del Espectro Autista [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/165871 / TESIS

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