http://hdl.handle.net/10092/10 2013-04-20T00:32:54Z http://hdl.handle.net/10092/7627 Title: Construction and testing of a next generation HTS partial-core transformer Authors: Lapthorn, A.C.; Bodger, P.S. Abstract: In 2005 the development of a 50Hz, 15 kVA, 230V:115V high temperature superconductor (HTS), partial core transformer was completed. The transformer was designed purely as a proof of concept, rather than as a unit that would be put into service. The transformer windings were layer wound using Bi2223 HTS tape from American Superconductors. The transformer failed while testing under full load with the internal primary winding failing to open circuit. This prompted an investigation into the cause of failure. Results from the investigation suggested the cause of failure to be a combination of operating near critical limits and insufficient cooling of the windings. This paper presents the design, construction, and testing of a next generation HTS partial core transformer. The design is based around the original 15 kVA HTS transformer with a new winding insulation system allowing improved cooling of the HTS wire. The windings are layer wound with first generation Bi2223 high temperature superconductor from Trithor Germany. A series of electrical tests were performed on the transformer including, open circuit, short circuit, resistive load, overload, ac withstand voltage, and fault ride through tests. The tests were conducted using international transformer testing standards as a guide where applicable. The transformer was found to be 98.2% efficient at rated power with 2.86% voltage regulation. 2012-01-01T00:00:00Z http://hdl.handle.net/10092/7625 Title: Identifizierbarkeit und Parameter Identifizierung in einem alveolaren Rekrutierungsmodell für die Atemmechanik Authors: Schranz, C.; Moller, K.; Docherty, P.D.; Chiew, Y.S.; Chase, J.G. Description: 1-page 2012-01-01T00:00:00Z http://hdl.handle.net/10092/7487 Title: Impact of calibration algorithms on hypoglycaemia detection in newborn infants using continuous glucose monitors Authors: Signal, M.; Le Compte, A.J.; Harris, D.L.; Weston, P.J.; Harding, J.E.; Chase, J.G. Abstract: Neonatal hypoglycaemia is a common condition that can cause seizures and serious brain injury in infants. It is diagnosed by blood glucose (BG) measurements, often taken several hours apart. Continuous glucose monitoring (CGM) devices can potentially improve hypoglycaemia detection, while reducing the number of BG measurements. Calibration algorithms convert the sensor signal into the CGM output. Thus, these algorithms can have a direct impact on measures used to quantify excursions from normal glycaemic levels. The aim of this study was to quantify the effects of calibration sensor error and non-linear filtering of CGM data on measures of hypoglycaemia (defined as BG < 2.6mmol/L) in neonates. CGM data was recalibrated using an algorithm that explicitly recognised the high accuracy of BG measurements available in this study. Median filtering was also implemented either before or after recalibration. Results for the entire cohort show an increase in the total number of hypoglycaemic events (161 to 193), duration of hypoglycaemia (2.2 to 2.6% of total data), and hypoglycaemic index (4.9 to 7.1µmol/L) after recalibration. With the addition of filtering, the number of hypoglycaemic events was reduced (193 to 131), with little or no change to the other metrics. These results show how reference sensor error and thus calibration algorithms play a significant role in quantifying hypoglycaemia. In particular, metrics such as counting the number of hypoglycaemic events were particularly sensitive to recalibration and filtering effects. While this conclusion might be expected, its potential impact is quantified here, in this case for at-risk neonates for whom hypoglycaemia carries potential long-term negative outcomes. Description: invited, 6-pages 2012-01-01T00:00:00Z http://hdl.handle.net/10092/7484 Title: Modelling prefabricated timber floors in fire Authors: O'Neill, J.; Abu, A.; Carradine, D.; Moss, P.; Buchanan, A. Abstract: Current regulations on the use of structural timber in large multi-storey buildings can be restrictive due to a perceived higher level of risk with regards to fire safety. This research investigates the fire performance of unprotected timber floors for use in these types of buildings, involving both modelling and experimental testing. To fully characterise the behaviour of composite timber floor systems in fires, 3D numerical modelling was performed using finite element software. In order to validate the numerical results, full scale furnace testing of the floors was undertaken at the Building Research Association of New Zealand. The final goal of this research is to develop simplified design models to reliably predict the expected fire resistance of these floors for different floor geometries, spans, materials and loading conditions. 2012-01-01T00:00:00Z