title: Innovative hybrid heat pump for dryer process integration

authors: Walmsley, Timothy Gordon

abstract: This study aims to simulate and optimise a hybrid compression-absorption heat pump process for convective dryers considering Pinch design principles. With a greening electricity grid, heat pumps represent an effective technology to reduce process heat emissions. As a result, numerous types of heat pumps integrated with convective dryers have been reported in the literature, but no study was found to use a hybrid heat pump. To simplify the design and optimisation, Process Integration principles for compressors and expanders from literature are synthesised into a Pinch design method for heat pumps. A milk spray dryer case study is analysed. Simulation results using Petro-Sim™ show that the optimally design hybrid heat pump system can reduce dryer energy demand by 47.3 % and total emissions by 42.4 % (assuming a low carbon electricity grid) while achieving a gross Coefficient of Performance of 4.53. Future work will look at optimising the selection and composition of working fluid for the hybrid heat pump system as well as investigating the economics of its implementation in industry.

text: Innovative hybrid heat pump for dryer process integration This study aims to simulate and optimise a hybrid compression-absorption heat pump process for convective dryers considering Pinch design principles. With a greening electricity grid, heat pumps represent an effective technology to reduce process heat emissions. As a result, numerous types of heat pumps integrated with convective dryers have been reported in the literature, but no study was found to use a hybrid heat pump. To simplify the design and optimisation, Process Integration principles for compressors and expanders from literature are synthesised into a Pinch design method for heat pumps. A milk spray dryer case study is analysed. Simulation results using Petro-Sim™ show that the optimally design hybrid heat pump system can reduce dryer energy demand by 47.3 % and total emissions by 42.4 % (assuming a low carbon electricity grid) while achieving a gross Coefficient of Performance of 4.53. Future work will look at optimising the selection and composition of working fluid for the hybrid heat pump system as well as investigating the economics of its implementation in industry.

year: 2017

title: Effective Linear-Time Feature Selection

authors: Pradhananga, Nripendra

subjects: filter

abstract: The classification learning task requires selection of a subset of features to represent patterns
to be classified. This is because the performance of the classifier and the cost of
classification are sensitive to the choice of the features used to construct the classifier.
Exhaustive search is impractical since it searches every possible combination of features.
The runtime of heuristic and random searches are better but the problem still persists
when dealing with high-dimensional datasets.
We investigate a heuristic, forward, wrapper-based approach, called Linear Sequential
Selection, which limits the search space at each iteration of the feature selection process.
We introduce randomization in the search space. The algorithm is called Randomized
Linear Sequential Selection. Our experiments demonstrate that both methods are faster,
find smaller subsets and can even increase the classification accuracy.
We also explore the idea of ensemble learning. We have proposed two ensemble creation
methods, Feature Selection Ensemble and Random Feature Ensemble. Both methods apply
a feature selection algorithm to create individual classifiers of the ensemble. Our
experiments have shown that both methods work well with high-dimensional data.

text: Effective Linear-Time Feature Selection The classification learning task requires selection of a subset of features to represent patterns
to be classified. This is because the performance of the classifier and the cost of
classification are sensitive to the choice of the features used to construct the classifier.
Exhaustive search is impractical since it searches every possible combination of features.
The runtime of heuristic and random searches are better but the problem still persists
when dealing with high-dimensional datasets.
We investigate a heuristic, forward, wrapper-based approach, called Linear Sequential
Selection, which limits the search space at each iteration of the feature selection process.
We introduce randomization in the search space. The algorithm is called Randomized
Linear Sequential Selection. Our experiments demonstrate that both methods are faster,
find smaller subsets and can even increase the classification accuracy.
We also explore the idea of ensemble learning. We have proposed two ensemble creation
methods, Feature Selection Ensemble and Random Feature Ensemble. Both methods apply
a feature selection algorithm to create individual classifiers of the ensemble. Our
experiments have shown that both methods work well with high-dimensional data.

year: 2007

title: Homai raa. Kia purutia, kia hereherea, taawhiwhi taamau. Ka pai. Taawhiwhi  taumau, he tauira waiora a Waikato : The creation of a Waikato-specific Maaori health model

authors: Haggie, Marrin Brian Pikitawhaki

subjects: Taawhiwhi Taamau

abstract: This Doctoral rangahau (research) sought to create a Maaori (Indigenous people of New Zealand) health model specific to the health needs and desires of the people of Waikato (The collective name of the tribes of the Waikato basin). Globally, minority populations (including Maaori) are consistently and disproportionately over represented in many health, education and incarceration statistics. Colonisation, oppression and racial prejudices have been identified as the root causes for the statistical imbalances prevalent in society. Indigenous populations have endured suffering caused by disconnection from heritage, traditional practices, ancestral beliefs and the natural environment. All are consequences of legislative enforcement and an oppressive, colonialist attitude that patronises indigenous populations (i.e., that assumes the coloniser knows what is best for the colonised). 

For the majority of colonisation, the health models and frameworks intended to benefit indigenous peoples, yet designed and implemented by colonial based, oppressive governments and by institutions rooted in colonialist ideals, have consistently failed to provide and deliver health and wellness for indigenous peoples. The fact that indigenous peoples’ health continues to be poorer than their non-indigenous counterparts, in the majority of health measures, suggests models and frameworks designed by non-indigenous people do not work for indigenous populations. This has led to an emergence of indigenous and minority populations’ movements seeking to emancipate themselves from the shackles of colonial oppression. 

Pioneering health models and frameworks designed to counter the failures of those designed by the oppressor have provided salvation for indigenous peoples and have allowed the voices of minority populations to be heard in the health and wellbeing context; however the majority of these models have been overly generic. Yet, they have provided foundations that now must be built upon to enable a focus on what specific populations require to ensure their health and lifestyle ideals are supported and strengthened.

As whaanau (family), marae (place of gathering and belonging for interrelated families), hapuu (subtribe), and as an iwi (tribe), Waikato have a responsibility to our taiao (natural environment), ourselves and to future generations to ensure the health of Waikato and that Waikatotanga (Waikato culture and practice) continues to grow, prosper, and flourish. Therefore, as a polity we must assert the control and direction of our iwi by determining and creating our own models and frameworks to ensure the survival, the growth, and the success of our people.

This Rangahau Kaupapa Waikato (Waikato focused research) is centered on the question ‘What elements must be considered in the creation and the application of a Waikato-specific, Maaori health model?’ Contemporary literature and research regarding health and the impacts on Indigenous and Maaori health specifically, was used to review the successes and failures of contemporary health models. 

Supported and framed by a Rangahau Kaupapa Maaori (Maaori focused research) approach, this Rangahau Kaupapa Waikato utilised Waikato koorero (stories), beliefs, practices and methodologies, interspersed with Qualitative Methodology and Thematic Analysis. Fourteen semi-structured interviews with tribal leaders and holders of tribal knowledge, referred to as taniwha, were conducted. Each taniwha shared their knowledge, understandings, and experiences to inform and contribute to the creation of a holistic health model specific to the iwi of Waikato.

The findings illustrate continued connection to the Waikato awa (river), the taiao (natural environment), wairuatanga (spirituality), ancestral knowledge and practices, the Kiingitanga (Maaori King Movement) and to the iwi itself are critical to the perpetuation of the waiora (health) of the Waikato iwi and of Waikatotanga in its multiple forms.

The model created as the primary outcome of this research, The Taawhiwhi Taamau Model of Waiora (Taawhiwhi Taamau), was designed to act as a vehicle which seeks to enable individual iwi members, and the polities that they belong, to achieve Mana-motuhake (autonomy) and self-determination of their own health. Taawhiwhi Taamau seeks to inform its adopters that Mana-motuhake can be achieved without having to compromise any of the tikanga (protocol) and kawa (custom) of our iwi and of our ancestors in favour of colonial government introduced, western ideals. Thereby removing the oppressor from the implementation and application of health. 

Taawhiwhi Taamau is a health model entrenched in Waikatotanga that utilises the beliefs and practices of our ancestors, and subsequently, our iwi to facilitate Tupuna (ancestor) Guided Living. The model encourages the individual iwi member to build solid foundations of waiora, seek knowledge and understanding of our tupuna, and use the experiences in life to act as taniwha for others seeking guidance, knowledge, connection, understanding and waiora. 

The adoption and practice of Taawhiwhi Taamau suggests individuals will find a new, refreshed connection to tupuna, maatauranga (wisdom, knowledge), wairuatanga and Waikatotanga, therefore, increasing waiora. Increased waiora of the individual increases the waiora and the capacity of one’s whaanau, marae and hapuu thereby increasing the waiora and the capacity of the iwi. Increased waiora and capacity of the iwi increases the likelihood of Waikatotanga, maatauranga, wairuatanga and, thus, the perpetuation of Tupuna Guided Living. Consequently, encapsulating the essence of Taawhiwhi Taamau as a model and as the lesson learned in the Pai Maarire Te Kura o te Ahiahi, ‘Homai ra, kia purutia, kia hereherea, taawhiwhi taamau. Ka Pai’.

text: Homai raa. Kia purutia, kia hereherea, taawhiwhi taamau. Ka pai. Taawhiwhi  taumau, he tauira waiora a Waikato : The creation of a Waikato-specific Maaori health model This Doctoral rangahau (research) sought to create a Maaori (Indigenous people of New Zealand) health model specific to the health needs and desires of the people of Waikato (The collective name of the tribes of the Waikato basin). Globally, minority populations (including Maaori) are consistently and disproportionately over represented in many health, education and incarceration statistics. Colonisation, oppression and racial prejudices have been identified as the root causes for the statistical imbalances prevalent in society. Indigenous populations have endured suffering caused by disconnection from heritage, traditional practices, ancestral beliefs and the natural environment. All are consequences of legislative enforcement and an oppressive, colonialist attitude that patronises indigenous populations (i.e., that assumes the coloniser knows what is best for the colonised). 

For the majority of colonisation, the health models and frameworks intended to benefit indigenous peoples, yet designed and implemented by colonial based, oppressive governments and by institutions rooted in colonialist ideals, have consistently failed to provide and deliver health and wellness for indigenous peoples. The fact that indigenous peoples’ health continues to be poorer than their non-indigenous counterparts, in the majority of health measures, suggests models and frameworks designed by non-indigenous people do not work for indigenous populations. This has led to an emergence of indigenous and minority populations’ movements seeking to emancipate themselves from the shackles of colonial oppression. 

Pioneering health models and frameworks designed to counter the failures of those designed by the oppressor have provided salvation for indigenous peoples and have allowed the voices of minority populations to be heard in the health and wellbeing context; however the majority of these models have been overly generic. Yet, they have provided foundations that now must be built upon to enable a focus on what specific populations require to ensure their health and lifestyle ideals are supported and strengthened.

As whaanau (family), marae (place of gathering and belonging for interrelated families), hapuu (subtribe), and as an iwi (tribe), Waikato have a responsibility to our taiao (natural environment), ourselves and to future generations to ensure the health of Waikato and that Waikatotanga (Waikato culture and practice) continues to grow, prosper, and flourish. Therefore, as a polity we must assert the control and direction of our iwi by determining and creating our own models and frameworks to ensure the survival, the growth, and the success of our people.

This Rangahau Kaupapa Waikato (Waikato focused research) is centered on the question ‘What elements must be considered in the creation and the application of a Waikato-specific, Maaori health model?’ Contemporary literature and research regarding health and the impacts on Indigenous and Maaori health specifically, was used to review the successes and failures of contemporary health models. 

Supported and framed by a Rangahau Kaupapa Maaori (Maaori focused research) approach, this Rangahau Kaupapa Waikato utilised Waikato koorero (stories), beliefs, practices and methodologies, interspersed with Qualitative Methodology and Thematic Analysis. Fourteen semi-structured interviews with tribal leaders and holders of tribal knowledge, referred to as taniwha, were conducted. Each taniwha shared their knowledge, understandings, and experiences to inform and contribute to the creation of a holistic health model specific to the iwi of Waikato.

The findings illustrate continued connection to the Waikato awa (river), the taiao (natural environment), wairuatanga (spirituality), ancestral knowledge and practices, the Kiingitanga (Maaori King Movement) and to the iwi itself are critical to the perpetuation of the waiora (health) of the Waikato iwi and of Waikatotanga in its multiple forms.

The model created as the primary outcome of this research, The Taawhiwhi Taamau Model of Waiora (Taawhiwhi Taamau), was designed to act as a vehicle which seeks to enable individual iwi members, and the polities that they belong, to achieve Mana-motuhake (autonomy) and self-determination of their own health. Taawhiwhi Taamau seeks to inform its adopters that Mana-motuhake can be achieved without having to compromise any of the tikanga (protocol) and kawa (custom) of our iwi and of our ancestors in favour of colonial government introduced, western ideals. Thereby removing the oppressor from the implementation and application of health. 

Taawhiwhi Taamau is a health model entrenched in Waikatotanga that utilises the beliefs and practices of our ancestors, and subsequently, our iwi to facilitate Tupuna (ancestor) Guided Living. The model encourages the individual iwi member to build solid foundations of waiora, seek knowledge and understanding of our tupuna, and use the experiences in life to act as taniwha for others seeking guidance, knowledge, connection, understanding and waiora. 

The adoption and practice of Taawhiwhi Taamau suggests individuals will find a new, refreshed connection to tupuna, maatauranga (wisdom, knowledge), wairuatanga and Waikatotanga, therefore, increasing waiora. Increased waiora of the individual increases the waiora and the capacity of one’s whaanau, marae and hapuu thereby increasing the waiora and the capacity of the iwi. Increased waiora and capacity of the iwi increases the likelihood of Waikatotanga, maatauranga, wairuatanga and, thus, the perpetuation of Tupuna Guided Living. Consequently, encapsulating the essence of Taawhiwhi Taamau as a model and as the lesson learned in the Pai Maarire Te Kura o te Ahiahi, ‘Homai ra, kia purutia, kia hereherea, taawhiwhi taamau. Ka Pai’.

year: 2021