title: Supecapacitor-assisted Temperature Modification Apparatus (SCATMA) and Fast Supercapacitor Charger

authors: Gurusinghe, Nicoloy

subjects: SCATMA

abstract: This thesis presents the design and development of the supercapacitor-assisted "instant" water heating system as well as a new power converter topology to fast charge a supercapacitor bank. 
Delayed delivery of hot water in domestic water heating systems wastes over 15 million cubic metres of treated water per annum in New Zealand. The patent pending supercapacitor assisted temperature modication apparatus (SCATMA), solves this problem by using pre-stored supercapacitor energy. These supercapacitors deliver short-term high-power bursts into heater coils placed in the final half meter of pipe connecting the faucet. During a period of less than a minute, 100-200 Wh of energy is released to the heater coil at a rate between 10-20 kW. 
Based on the cost constraints of a commercial system and the regulatory authority requirements, a supercapacitor-only solution becomes prohibitively expensive. A review of current state-of-the-art energy storage systems show that no battery chemistry can withstand the associated charge-discharge cycles to reach the expected service life of 5-10 years. While developing the unique two-stage fast supercapacitor charger, a battery-supercapacitor hybrid system was developed for SCATMA as a commercially viable solution for rapid water heating.
Dividing a supercapacitor bank into three parts and circulating them through a `charge-idle-discharge' sequence was already investigated for the surge resistant uninterrupted power supply. The effectiveness of this technique mandates fast supercapacitor charging. The proposed new charger achieves fast charging by using a high voltage source to overcome the five time constant charging time and a series coupled inductor to charge the capacitor bank by dividing it into two parts. One part is charged using an overvoltaged dc source with capacitor bank terminal voltage monitoring and the other part is charged by the coupled-inductor using the energy stored in the inductor. 
This topology is specifically developed for applications with limited energy requirements. Design procedure and results for a 600 W, 2 Wh charger is presented to illustrate the fast charging ability, the inherent power factor correction capability and the scalability of the topology.

text: Supecapacitor-assisted Temperature Modification Apparatus (SCATMA) and Fast Supercapacitor Charger This thesis presents the design and development of the supercapacitor-assisted "instant" water heating system as well as a new power converter topology to fast charge a supercapacitor bank. 
Delayed delivery of hot water in domestic water heating systems wastes over 15 million cubic metres of treated water per annum in New Zealand. The patent pending supercapacitor assisted temperature modication apparatus (SCATMA), solves this problem by using pre-stored supercapacitor energy. These supercapacitors deliver short-term high-power bursts into heater coils placed in the final half meter of pipe connecting the faucet. During a period of less than a minute, 100-200 Wh of energy is released to the heater coil at a rate between 10-20 kW. 
Based on the cost constraints of a commercial system and the regulatory authority requirements, a supercapacitor-only solution becomes prohibitively expensive. A review of current state-of-the-art energy storage systems show that no battery chemistry can withstand the associated charge-discharge cycles to reach the expected service life of 5-10 years. While developing the unique two-stage fast supercapacitor charger, a battery-supercapacitor hybrid system was developed for SCATMA as a commercially viable solution for rapid water heating.
Dividing a supercapacitor bank into three parts and circulating them through a `charge-idle-discharge' sequence was already investigated for the surge resistant uninterrupted power supply. The effectiveness of this technique mandates fast supercapacitor charging. The proposed new charger achieves fast charging by using a high voltage source to overcome the five time constant charging time and a series coupled inductor to charge the capacitor bank by dividing it into two parts. One part is charged using an overvoltaged dc source with capacitor bank terminal voltage monitoring and the other part is charged by the coupled-inductor using the energy stored in the inductor. 
This topology is specifically developed for applications with limited energy requirements. Design procedure and results for a 600 W, 2 Wh charger is presented to illustrate the fast charging ability, the inherent power factor correction capability and the scalability of the topology.

year: 2016

title: The hydrodynamics of the southern basin of Tauranga Harbour

authors: Tay, H.W.

subjects: hydrodynamic model

abstract: The circulation of the southern basin of Tauranga Harbour was simulated using a 3-D hydrodynamic model ELCOM. A 9-day field campaign in 1999 provided data on current velocity, temperature and salinity profiles at three stations within the main basin. The tidal wave changed most in amplitude and speed in the constricted entrances to channels, for example the M2 tide attenuated by 10% over 500 m at the main entrance, and only an additional 17% over the 15 km to the top of the southern basin. The modelled temperature was sensitive to wind mixing, particularly in tidal flat regions. Residence times ranged from 3 to 8 days, with higher residence times occurring in sub-estuaries with constricted mouths. The typical annual storm events were predicted to reduce the residence times by 24%–39% depending on season. Model scenarios of storm discharge events in the Wairoa River varying from 41.69 m3/s to 175.9 m3/s show that these events can cause salinity gradients across the harbour of up to 4 PSU.

text: The hydrodynamics of the southern basin of Tauranga Harbour The circulation of the southern basin of Tauranga Harbour was simulated using a 3-D hydrodynamic model ELCOM. A 9-day field campaign in 1999 provided data on current velocity, temperature and salinity profiles at three stations within the main basin. The tidal wave changed most in amplitude and speed in the constricted entrances to channels, for example the M2 tide attenuated by 10% over 500 m at the main entrance, and only an additional 17% over the 15 km to the top of the southern basin. The modelled temperature was sensitive to wind mixing, particularly in tidal flat regions. Residence times ranged from 3 to 8 days, with higher residence times occurring in sub-estuaries with constricted mouths. The typical annual storm events were predicted to reduce the residence times by 24%–39% depending on season. Model scenarios of storm discharge events in the Wairoa River varying from 41.69 m3/s to 175.9 m3/s show that these events can cause salinity gradients across the harbour of up to 4 PSU.

year: 2013

title: Kua Hiri Mai Te Rā - A journey of self identification for the descendants of Ngāti Rāhiri ki Taranaki

authors: Marsh, Melissa Sue-ann

subjects: Ngāti Rāhiri

abstract: Prior to the arrival of Pakehā to the shores of Aotearoa, Māori retained and transmitted their histories, genealogies and protocols orally through such mediums as song and chant. The intracacies of the information held was such that every aspect of the Māori culture had its assigned expert whose job was to both retain and pass on their area of expertise. The settlement of Pakehā saw a change in how information was stored and disseminated, with a number of ethnographers, surveyors and historians recording accounts given to them from various Māori sources in written form. The main motivation for this at the time was to secure the information and cultural practises of a people who were deemed to be a dying race.

The implication that Māori were close to extinction was in vain, as many resisted against the gradual assimilation of Aotearoa (New Zealand) by the new foreign immigrants. The subsequent annexation of Aotearoa under British colonial rule eventually led to war against Māori, as Māori attempted to protect and retain both their lands and their identity. The result of the war led to a great loss of Māori lands, lives, and most importantly – identity.

Within Taranaki the Ngāti Rāhiri Hapū fought many generations for the right to stand unified as a people. Although they can be regarded as a small coastal hapū entity, they are at the forefront of maintaining and asserting their rangatiratanga status within today’s society. At the centre of the proclamation of rights and entitlement within their ancestral lands, questions have been raised that, for a number of generations, had baffled the likes of Elsdon Best and S. Percy Smith, as many sought to find answers regarding the true origins of Ngāti Rāhiri.

The impetus in undertaking this research is to ascertain who this prominent ancestor Rāhiri is from both a Ngā Puhi and Taranaki perspective, and investigate how these combined histories assist in the assertion of self by the Ngāti Rāhiri ki Taranaki people. By undertaking a critical review and analysis of literature, court minute records, hapū documents, proverbs, histories and knowledge from tribal elders pertaining to Rāhiri, this researcher will endeavour to provide and present relevant information and evidence, in a cohesive format, to show the close ancestral ties and affiliations between the two peoples. Furthermore, it is hoped that the research findings presented within this body of work may provide a significant contribution to the descendants of the Ngāti Rāhiri ki Taranaki Hapū, as they continue to assert their mana and rangatiratanga through the knowledge and understanding of self, when posed with the question - Ko wai a Ngāti Rāhiri?

text: Kua Hiri Mai Te Rā - A journey of self identification for the descendants of Ngāti Rāhiri ki Taranaki Prior to the arrival of Pakehā to the shores of Aotearoa, Māori retained and transmitted their histories, genealogies and protocols orally through such mediums as song and chant. The intracacies of the information held was such that every aspect of the Māori culture had its assigned expert whose job was to both retain and pass on their area of expertise. The settlement of Pakehā saw a change in how information was stored and disseminated, with a number of ethnographers, surveyors and historians recording accounts given to them from various Māori sources in written form. The main motivation for this at the time was to secure the information and cultural practises of a people who were deemed to be a dying race.

The implication that Māori were close to extinction was in vain, as many resisted against the gradual assimilation of Aotearoa (New Zealand) by the new foreign immigrants. The subsequent annexation of Aotearoa under British colonial rule eventually led to war against Māori, as Māori attempted to protect and retain both their lands and their identity. The result of the war led to a great loss of Māori lands, lives, and most importantly – identity.

Within Taranaki the Ngāti Rāhiri Hapū fought many generations for the right to stand unified as a people. Although they can be regarded as a small coastal hapū entity, they are at the forefront of maintaining and asserting their rangatiratanga status within today’s society. At the centre of the proclamation of rights and entitlement within their ancestral lands, questions have been raised that, for a number of generations, had baffled the likes of Elsdon Best and S. Percy Smith, as many sought to find answers regarding the true origins of Ngāti Rāhiri.

The impetus in undertaking this research is to ascertain who this prominent ancestor Rāhiri is from both a Ngā Puhi and Taranaki perspective, and investigate how these combined histories assist in the assertion of self by the Ngāti Rāhiri ki Taranaki people. By undertaking a critical review and analysis of literature, court minute records, hapū documents, proverbs, histories and knowledge from tribal elders pertaining to Rāhiri, this researcher will endeavour to provide and present relevant information and evidence, in a cohesive format, to show the close ancestral ties and affiliations between the two peoples. Furthermore, it is hoped that the research findings presented within this body of work may provide a significant contribution to the descendants of the Ngāti Rāhiri ki Taranaki Hapū, as they continue to assert their mana and rangatiratanga through the knowledge and understanding of self, when posed with the question - Ko wai a Ngāti Rāhiri?

year: 2011