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Full-Text Articles in Physics
Comparison Of Auto-Adjusting And Fixed Level Continuous Positive Airway Pressure Therapy In Patients With Mild To Moderate Obstructive Sleep Apnoea Hypopnoea Syndrome, Geraldine Nolan
Masters
Obstructive Sleep Apnoea Hypopnoea syndrome (OSAHS) is a potentially serious medical disorder associated with increased morbidity and mortality. It is estimated to affect 4% of males and 2% of females between the ages of forty and sixty. Nasal continuous positive airway pressure (CPAP) is the first choice treatment for this condition and it is extremely effective at controlling OSAHS. However, not all patients can tolerate this therapy, in particular those within the mild to moderate category, and there are also many others who are unable to comply with the minimum usage requirements of at least four hours every night. A …
Optimisation Of Organic Materials For Laser Applications, Kieran P. Henderson
Optimisation Of Organic Materials For Laser Applications, Kieran P. Henderson
Masters
This project sets out to investigate the variations of the optical properties of organic conjugated polymers with a view towards understanding the transition from isolated molecule (solution) to the solid state. The polymer poly9p-phenylene vinylene-co-2,5-dioctyloxy-m-phenylene vinylene) (PmPV) is chosen as it is of interest for both light emitting and nanotube composite applications. As a model compound, 2,5-dioctoxy-p-distrylbenzene, termed the trimer, is employed for comparison. The objective are to characterize the effect of the environment, using solvent and concentration dependent studies, on the optical properties of the polymer and to compare the results for the more complex polymeric system to the …
High-Speed Electronic Speckle Pattern Interferometry, Carol Armstrong
High-Speed Electronic Speckle Pattern Interferometry, Carol Armstrong
Masters
Electronic Speckle Pattern Interferometry (ESPI) is used to measure surface displacements. Phase shifting can be used to obtain a fringe pattern which depicts the phase at every point in an image. Previous studies have used algorithms such as the 4-bucket algorithm to obtain phase maps of objects. After the object is displaced a second phase map is obtained in the same way and by correlation the phase difference due to the displacement can be determined. When the object is in rapid continuous motion these algorithms cannot be used. Towards this end a 5-frame algorithm was written, in which the calibrated …
Studies In Cardiac Defribrillation, Eamonn Mckenna
Studies In Cardiac Defribrillation, Eamonn Mckenna
Masters
Cardiac disease resulting in cardiac arrest is one of the most common fatal diseases in the developed world. Defibrillation is the medical procedure used to correct the irregular cardiac rhythm (ventricular fibrillation (VF)) which is very often detected in patients suffering cardiac arrest. In the work reported in this thesis, two aspects of the defibrillation of patients in VF were examined. The first area of investigation concentrated on the use of multiple defibrillation electrodes to be used during closed chest (transthoracic) defibrillation. This study was carried out in a saline bath and centred on “focusing” electric fields from perimeter electrodes …
Non Linear Electronic And Optical Processes In Fullerene Thin Films, Siobhan Phelan
Non Linear Electronic And Optical Processes In Fullerene Thin Films, Siobhan Phelan
Masters
In this study the current voltage characteristics of C60 thin film sandwich structures fabricated by vacuum deposition on indium tin oxide (ITO) with an aluminium top electrode are presented and discussed. A strongly non-linear behaviour and a sharp increase in the device conductivity was observed at relatively low voltages, at both room and low temperatures (30K). At room temperature the system is seen to collapse. In situ Raman measurements indicate that the collapse is the result of a solid state reduction of the fullerene thin film to a polymeric state. The high conductivity state was seen to be stable at …
Crash Analysis: An Investigation Of Current Speed Estimation Techniques, Robert Rice
Crash Analysis: An Investigation Of Current Speed Estimation Techniques, Robert Rice
Masters
The increasing number of cars and collisions on the roads of Europe ensure that the need for accurate speed estimation is an ever-more pressing requirement. This requirement has provided the motivation for an investigation into the accuracy and reliability of existing crash models An in-depth literature review was undertaken to create a greater understanding of the structural collapse behaviour of vehicles during full frontal collisions. It was decided to concentrate the work on frontal collisions as this type of accident makes up the majority of road accidents. This review underlined some of the phenomena that need to be considered when …