title: Supercapacitor assisted power converter for DC microgrid applications with self-contained DC-UPS capability

authors: Hu, Yang

subjects: DC microgrid

abstract: Nowadays, due to the advantages inherent in using renewable energy, renewable power generation is becoming established worldwide. Direct current (DC) microgrid systems, which have been proposed as alternatives for traditional alternating current (AC) networks, enable the introduction of a large amount of solar energy by using distributed photovoltaic generation units. Meanwhile, small-scale DC microgrid systems designed at the household level are also viable options used to harness renewable energy (like solar energy) and have broad development prospects.
One of the ‘hot topics’ in the field of renewable energies is how to make efficient use of this type of energy. In this thesis, a high-efficiency DC microgrid system with supercapacitor (SC)-assisted power converter is introduced as a way to harness solar energy to run a 12 V, 50 W household lighting system.
Supercapacitor-assisted low dropout regulator (SCALDO) techniques were used to build an SC-assisted converter for a DC microgrid system. Supercapacitors in the DC microgrid acted as voltage droppers to convert 24 V solar panel’s output to 11 V – 13 V. Supercapacitors were also used as energy storage devices, and performed as a power source to run the household lighting system for a period of time after a sudden mains power outage.
Real weather condition data, including local Hamilton illuminance values, were required to design this system. These data were measured at the University of Waikato. They were converted into irradiance data and were used to create similar patterns for simulation. Prototype circuit of the complete DC microgrid system, with an SC-assisted converter was also developed and shown at the end of the thesis.

text: Supercapacitor assisted power converter for DC microgrid applications with self-contained DC-UPS capability Nowadays, due to the advantages inherent in using renewable energy, renewable power generation is becoming established worldwide. Direct current (DC) microgrid systems, which have been proposed as alternatives for traditional alternating current (AC) networks, enable the introduction of a large amount of solar energy by using distributed photovoltaic generation units. Meanwhile, small-scale DC microgrid systems designed at the household level are also viable options used to harness renewable energy (like solar energy) and have broad development prospects.
One of the ‘hot topics’ in the field of renewable energies is how to make efficient use of this type of energy. In this thesis, a high-efficiency DC microgrid system with supercapacitor (SC)-assisted power converter is introduced as a way to harness solar energy to run a 12 V, 50 W household lighting system.
Supercapacitor-assisted low dropout regulator (SCALDO) techniques were used to build an SC-assisted converter for a DC microgrid system. Supercapacitors in the DC microgrid acted as voltage droppers to convert 24 V solar panel’s output to 11 V – 13 V. Supercapacitors were also used as energy storage devices, and performed as a power source to run the household lighting system for a period of time after a sudden mains power outage.
Real weather condition data, including local Hamilton illuminance values, were required to design this system. These data were measured at the University of Waikato. They were converted into irradiance data and were used to create similar patterns for simulation. Prototype circuit of the complete DC microgrid system, with an SC-assisted converter was also developed and shown at the end of the thesis.

year: 2017

title: Exploring Representations of Interactive Space

authors: Browne, Jordan

subjects: Interactive

abstract: Space has been conceived in many different ways by as many different disciplines. Lefebvre and Harvey suggest conceptions of space as approaches to understanding human interactions within our world. These same conceptions can be employed in a discussion of interactive space and how it is experienced and engaged with. Additionally, the very nature of interactivity facilitates other ideas that can be used to understand its landscape such as recursive space and the notion of how a person's perception of a space impacts their engagement with it.

This research explores representations of interactive space within screen mediated environments. The work uses existing conceptions of space to understand interactivity as well as to inform new ways of challenging the stability of these spaces both theoretically and practically. The project takes a practice-led approach involving the creation and conceptualisation of my own work to theorise some of the possibilities of interactive media. The intent of this study is not so much to define interactive space in its entirety but rather to explore some of the potential ways that it can be theorised using a practice-led approach through the theoretical frameworks of assemblage and affect which, for me, are deeply embedded in the constructions of these spaces.

text: Exploring Representations of Interactive Space Space has been conceived in many different ways by as many different disciplines. Lefebvre and Harvey suggest conceptions of space as approaches to understanding human interactions within our world. These same conceptions can be employed in a discussion of interactive space and how it is experienced and engaged with. Additionally, the very nature of interactivity facilitates other ideas that can be used to understand its landscape such as recursive space and the notion of how a person's perception of a space impacts their engagement with it.

This research explores representations of interactive space within screen mediated environments. The work uses existing conceptions of space to understand interactivity as well as to inform new ways of challenging the stability of these spaces both theoretically and practically. The project takes a practice-led approach involving the creation and conceptualisation of my own work to theorise some of the possibilities of interactive media. The intent of this study is not so much to define interactive space in its entirety but rather to explore some of the potential ways that it can be theorised using a practice-led approach through the theoretical frameworks of assemblage and affect which, for me, are deeply embedded in the constructions of these spaces.

year: 2013

title: Understanding the context of hospital transfers and away-from-home hospitalisations for Māori

authors: Cormack, Donna

subjects: Humans

abstract: In Aotearoa New Zealand, people regularly travel away from their home to receive hospital care. While the role of whānau support for patients in hospital is critical for Māori, there is little information about away-from-home hospitalisations. This paper describes the frequency and patterning of away-from-home hospitalisations and inter-hospital transfers for Māori. Data from the National Minimum Dataset (NMDS), for the 6-year period of 1 January 2009-31 December 2014, were analysed. Basic frequencies, means and descriptive statistics were produced using SAS software. We found that more than 10% of all routine hospitalisations constituted an away-from-home hospitalisation for Māori; that is, a hospitalisation that was in a district health board (DHB) other than the DHB of usual residence for the patient. One quarter (25.19%) of transfer hospitalisations were to a DHB other than the patient's DHB of domicile. Away-from-home hospital admissions increase for Māori as deprivation increases for both routine and transfer admissions, with over half of Māori hospital admissions among people who live in areas of high deprivation. This analysis aids in understanding away-from-home hospitalisations for Māori whānau, the characteristics associated with these types of hospitalisations and supports the development and implementation of policies which better meet whānau Māori needs. The cumulative impact of the need to travel to hospital for care, levels of poverty and a primarily reimbursement-based travel assistance system all perpetuate an unequal cost burden placed upon Māori whānau.

text: Understanding the context of hospital transfers and away-from-home hospitalisations for Māori In Aotearoa New Zealand, people regularly travel away from their home to receive hospital care. While the role of whānau support for patients in hospital is critical for Māori, there is little information about away-from-home hospitalisations. This paper describes the frequency and patterning of away-from-home hospitalisations and inter-hospital transfers for Māori. Data from the National Minimum Dataset (NMDS), for the 6-year period of 1 January 2009-31 December 2014, were analysed. Basic frequencies, means and descriptive statistics were produced using SAS software. We found that more than 10% of all routine hospitalisations constituted an away-from-home hospitalisation for Māori; that is, a hospitalisation that was in a district health board (DHB) other than the DHB of usual residence for the patient. One quarter (25.19%) of transfer hospitalisations were to a DHB other than the patient's DHB of domicile. Away-from-home hospital admissions increase for Māori as deprivation increases for both routine and transfer admissions, with over half of Māori hospital admissions among people who live in areas of high deprivation. This analysis aids in understanding away-from-home hospitalisations for Māori whānau, the characteristics associated with these types of hospitalisations and supports the development and implementation of policies which better meet whānau Māori needs. The cumulative impact of the need to travel to hospital for care, levels of poverty and a primarily reimbursement-based travel assistance system all perpetuate an unequal cost burden placed upon Māori whānau.

year: 2022-11-11