Higher Degree Theses

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Integrating behavioural and formal specifications
(Thesis, The University of Waikato, 2024) Liu, Bowen
Behaviour-driven development and formal methods have been shown to be effective techniques for different parts of the interactive system development process. However, when the different parts of an interactive system are combined, issues may arise due to the different focuses of the techniques. For a safety-critical interactive system, where safety is particularly emphasised, using either technique individually does not cover all aspects of the system. Thus a complementary approach of integrating behaviour-driven development and formal methods, would be better suited for developing safety-critical interactive systems. This thesis presents an investigation into a method that integrates formal methods and behavioural specifications. This method enables the identification of any inconsistencies between the behavioural specification and the Z specification, allowing potential problems to be found and fixed earlier. We also demonstrate how our method supports ensuring consistency after refinement of the Z specification.
Maldivian primary teachers activate and shape their Social Studies pedagogies through reflection
(Thesis, The University of Waikato, 2024) Saeed, Sharuda
This study emerges from a deep-seated concern about the potential erosion of Maldivian cultural heritage and identity, reflected in the diminishing prominence of traditional cultural practices, language, beliefs, which are often threatened by tourism and foreign influences. The research investigates how Maldivian primary teachers perceive and teach social studies, a subject crucial for preserving cultural identity and for promoting sustainable development. As a Maldivian social studies educator, I view social studies education as an empowering force for fostering critical thinking, empathy, and global citizenship among future leaders. The research explores how primary teachers activate and shape their social studies pedagogy through reflection, with a focus on Key Stage 1 and 2 levels. Some findings indicate that teachers face challenges due to limited access to specialised professional learning, resulting pedagogical approaches that are often teacher-led and exam focused, rather than being inquiry-based and student-centred. This thesis sheds light on these dynamics and contributes to critical need for educational reform conversations in the Maldives on the quality of social studies education. Conducted during the COVID-19 pandemic, this largely qualitative study initially adopted a Participatory Action Research [PAR] methodology and later transitioned to Online Participatory Action Research [OPAR]. Data was collected from ten participants via a Qualtrics questionnaire and online workshops, with four teachers contributing reflective narrative texts and participating in online interviews. Thematic analysis and grounded theory guided the analysis, which uncovered key themes and generating theoretical insights drawn from the firsthand experiences of the participants within the realm of social studies education in the Maldives. The findings highlight the crucial role of reflective practice in shaping pedagogy and fostering professional growth. Analysis of teachers’ experiences suggested how reflective practice influences their social studies teaching, helping them adapt to the evolving educational landscape in the Maldives. The study also highlights strategies teachers employ to navigate challenges, and illustrated the practical impact of reflective practice on improving teaching, learning, and ongoing professional development for Maldivian social studies teachers. Four key implications arise from this study. First, the study highlights the importance of understanding teachers’ perceptions of social studies within the National Curriculum Framework, and the need for more targeted exploration of its significance. Second, it underscores the need to address challenges in professional learning, with recommending tailored interventions to enhance teachers’ social studies pedagogy being necessary. Third, the research emphasises the role of reflective practice in shaping teaching methods and urges educational institutions, including the Maldives National University, to integrate reflective strategies into teacher training. Finally, the findings advocate for policy initiatives and support structures to create an environment that fosters reflective practices, enhancing social studies education in primary schools.
COVID-19, capital flows and sustainable development in Sub-Saharan Africa
(Thesis, The University of Waikato, 2025) Shittu, Waliu Olawale
The Sub-Saharan Africa (SSA) region suffered severe economic impacts from COVID-19, despite experiencing some of the lowest numbers of cases and deaths from the pandemic. The attainment of sustainable development in the region was significantly affected partly because of the region’s huge reliance on industrialised economies who were most hit by the pandemic. The SSA countries covered 33 of the 45 countries listed by the United Nations Conference on Trade and Development (UNCTAD) as least developed countries (LDCs) requiring significant assistance. Moreover, the countries in the region experience some of the lowest inflows of foreign direct investment (FDI), both in comparison to other regions and to the flow of other foreign capitals into SSA. Again, as these countries were more vulnerable to economic shocks because of their lower resilience capacities, the attainment of sustainable development was significantly threatened when COVID-19 resulted in reduced economic activity, foreign investment and deteriorating socio-economic inequalities. Although earlier studies have concentrated on the impact of various cross-border capital flows on economic growth and some development indicators, those studies have not empirically evaluated how this global shock has impacted the inflows of foreign capital and their effects on sustainable development. In view of these, this thesis provides three empirical studies, using data from SSA countries over the period 2000 – 2022. The first paper evaluated the impact of COVID-19 on the nexus between remittances and sustainable development. Relying on both static and dynamic estimation techniques, the study found that remittance is positively associated with sustainable development, both before and after the threshold, subject to the absorptive capacity of the SSA economies. In effect, there is a minimum level of institutional quality and financial development, below which their effects on sustainable development would be negative; at which the stimulating effect of remittances may be reversed. In addition, COVID-19 was observed to reduce the progress towards sustainable development, directly and when interacted with remittances. In the second paper, the impact of the pandemic was estimated in the nexus between FDI and sustainable development. The empirical estimates showed that FDI does not exert a significant impact on sustainable development. When the effect of FDI was further analysed on economic growth, the environment, and human development, the estimates remained consistent. While COVID-19 was found to reduce the levels of economic growth, the environment, human development, and sustainable development, the interaction effect showed that FDI reduces the negative effect of COVID-19 on economic growth and sustainable development. The third paper measured the impact of COVID-19 on the aid – sustainable development nexus. The findings revealed that foreign aid facilitates the attainment of sustainable development and many of its goals. Even though the pandemic was found to exert a diminishing effect, foreign aid was not only found to reduce the negative effect of the pandemic but to also enhance the complementary roles of financial and institutional infrastructures on the attainment of sustainable development.
Experiences of people with refugee background who started their business in the food sector
(Thesis, The University of Waikato, 2024) Bazrafshan, Shima
The emotional and relational aspects of hospitality for inclusion have been rarely explicitly acknowledged in the food business sector and academic scholarship. Embedded within these aspects is the concept of voice and how it can be used to empower and care for others. Voice is viewed as a fundamental human right and is crucial for communities, such as those with refugee background to express their experiences and gain agency for change. How stories are told using food and within hospitality businesses, illuminates care, as well as communicating the causes of displacement and refugee experiences during their journeys, arrival, collective perceptions and the reception and inclusion of refugees in the countries in which they resettle. A key approach for gaining inclusion and economic resources for refugee background communities has been to start a business. This provides opportunities for employment and, the hospitality and food sector, has been viewed as an accessible sector for refugee-background individuals to start their venture in and offer a transformative avenue for inclusion in their new communities. Through their hospitality and food businesses, refugees can offer positive narratives, challenge perceptions that others in the host community may have of them and construct realistic caring representations of themselves. The hospitality sector emerges as a unique platform for refugees to connect with host communities, fostering mutual understanding and promoting inclusion. Previous academic studies that have investigated hospitality businesses started by people with refugee background have mainly focused on examining the various economic and functional aspects that influence their businesses. In these studies, a humanitarian approach that examined the sociological and cultural role of food and food businesses for diverse communities such as refugee background individuals was rarely acknowledged. To deepen our understanding of the role of food and hospitality for people with refugee background who started hospitality businesses, this thesis highlights the critical sociocultural and symbolic aspects of food. To focus on participants’ perspectives of food, their meanings of their food business experiences and values, an interpretative approach was deemed appropriate for the thesis. Critical hospitality theory was included in the analysis to examine how food provides a conduit to create meaningful relationships with ‘Others’ that goes beyond economics or biological needs. Memory-work methodology was seen as an appropriate method and offered opportunities for participants to consider the narrative that they wanted to share in a meaningful manner in the research. Located within the interpretive paradigm, memory-work is grounded in understanding the world as being interpreted by individuals in their lived practices of everyday life. 12 participants volunteered to write a memory and reflect on their experience with me in individual discussion meetings. Institutional ethics for the research was approved by the Waikato Management School Research Ethics Committee. Thematic analysis of the data indicated three significant themes that represented the participants’ experiences: ‘People with refugee background as caregivers’; ‘Strangers encounter, strangers become familiar’; and ‘Fostering emotional solidarity with people with refugee background’. People with refugee background are usually portrayed as perpetually vulnerable and reliant individuals who need or want support and care from national and international organisations to assist them in navigating their way into the new society. However, rather than conforming to this stereotypical portrayal of refugees as passive care receivers, people with refugee background who participated in this research were actively engaged in providing care for others. The findings of this research also illustrated that hospitality in this type of commercial setting was a catalyst for dialogue and exchange of ideas, experiences, and knowledge between different ‘others’ that allowed strangers to be welcomed as familiars. In the context of hospitality, refugee-background participants stated that their customers developed some emotional solidarity with the experiences of people from refugee-background communities. This thesis contributes to a richer understanding of how the commercial context of hospitality can create opportunities for crossing thresholds, activism for change, and inclusion. Notably, this thesis uncovers how food and hospitality businesses could sustain well-being, care for the ‘other’ and act as a channel to advocate for change around refugee-background issues.
Construction and demolition waste as low-cost materials for the removal of heavy metal ions from wastewater
(Thesis, The University of Waikato, 2024) Ranaweera Arachchige, Kavitha Harshani
Water pollution due to heavy metal ion contaminations and management of construction and demolition waste (CDW) are two major environmental issues faced by the world today. Exposure to heavy metal ions can cause serious health problems, and therefore, treatment of heavy metal contaminated water/wastewater to protect the environment and people is essential. The management of CDW has become a serious problem due to the large amounts generated each year. Only a small percentage of this waste is recycled, while the majority is disposed of in landfills with space running out to accommodate these materials. Repurposing CDW as low-cost materials for heavy metal ion treatment is thus a promising strategy as this not only contributes to CDW management but also to heavy metal ion remediation. The research described in this thesis investigated the applicability of five CDW materials (particle board wood dust (PBW), medium density fiberboard (MDF) fines, biochar derived from particle board offcuts (PBB), Gibraltar board fines (GBF), and demolished concrete (DC)) for the treatment of Cd(II), Cu(II), Pb(II), and Zn(II) ions. The selected CDW materials were characterized by performing FTIR, SEM-EDX, TGA, XRD, and surface area analysis to identify the composition and nature of these materials. The effect of different parameters (metal ion type, contact time, initial metal ion concentration, pH, and material dosage) on the heavy metal ion removal process was investigated in single metal ion solution systems utilizing a batch method. All studied materials exhibited high removal efficiency for Pb(II) ions compared to the other metal ions except DC, which showed high removal efficiency towards Cu(II) ions. Therefore, Pb(II) was selected to evaluate the effect of other parameters for PBW, MDF fines, PBB, and GBF, whilst Cu(II) was used for DC. The results indicated that the main heavy metal ion removal mechanism of PBW, MDF fines, and PBB was adsorption, while DC and GBF utilized precipitation. The effect of competitive metal ions on the heavy metal ion removal ii process was investigated using a Cd(II)-Cu(II) multi-metal ion system for DC and a Cd(II)-Pb(II) multi-metal ion system for other materials using a batch method. The results indicated that the presence of Cd(II) ions reduced Pb(II) ion removal efficiency for PBW, MDF fines, and PBB and Cu(II) ion removal efficiency of DC. However, Pb(II) ion removal by GBF was not affected. Experiments were carried out to investigate whether the selected CDW materials leached out any toxic substances. The results indicated that PBW and MDF fines increased TOC concentrations, while GBF increased calcium and sulfate concentrations in treated water. Adsorption isothermal, kinetic, and adsorbent regeneration studies were carried out for CDW materials which utilized adsorption for the heavy metal ion removal. Adsorption isothermal studies were performed for single metal ion systems, and the Freundlich isotherm model fitted better with the experimental data of all studied materials. Adsorption kinetics of both single and multi-metal ion systems were evaluated, and the experimental data fitted better with either pseudo-second-order or Elovich kinetic models for all studied systems. The adsorbent regeneration studies were performed using 0.1 M HCl as a regeneration agent for three adsorption-desorption cycles for both metal ion systems. High % desorption values were obtained during the first cycle, however, the adsorption capacity was reduced in the subsequent cycles for all studied adsorption systems. Column analyses were conducted for GBF and PBB for both single (Pb(II)) and multi-metal ion systems (Cd(II)-Pb(II)). High % removal values were obtained for Pb(II) ions in both metal ion systems for both materials. The experimental data of the PBB was fitted to column adsorption models as PBB utilized adsorption for heavy metal ion removal, and the Yan model fitted well with the experimental data of both metal ion systems. The results indicate that CDW materials have potential for heavy metal ion treatment. Further research is required to investigate the applicability of these materials in real-world applications.
The chronology of Waikato pā: A spatio-temporal investigation of pā in the middle Waikato basin
(Thesis, The University of Waikato, 2024) McBride, Rowan
This study considers the chronology of pā construction, proliferation, and development within the Middle Waikato Basin through a spatio-temporal investigation of palisade construction activity as identified at six pā (fortified places). The chronological approach applied in this thesis uses 14C wiggle-match dating to provide an accurate and precise calendar date for the felling of a tree (Felling Date) used to construct a palisade defence at a pā. These Felling Dates are interpreted using the theory of time perspectivism, focusing on three distinct scales of analysis: Event, Local, and Regional. The event scale of analysis successfully produced twenty high-precision felling dates on posts recovered from Lake Mangakaware 1 (MA1), Lake Mangakaware 2 (MA2), Lake Mangahia (MGA), Taraheke Pā (TAR), Te Uapata Pā (TEU) and Lake Rotokauri (ROT). The local scale analysis utilised these felling dates to track the development of the identified palisade defences over time, identifying multiple palisade construction phases, representing construction, repair and redevelopment episodes at MA1, MA2, MGA, TAR and TEU. Finally, the regional scale analysis integrated this evidence into a broader chronological framework, identifying shared episodes of palisade construction activity within the Middle Waikato Basin. This analysis highlights three critical periods of proposed socio-political stress and stability between the late fifteenth and early nineteenth centuries, related to hypothesised influential variables from the broader cultural and archaeological landscape that are proposed to be responsible for the emergence, proliferation and development of pā over time.
Clustering using finite mixture models
(Thesis, The University of Waikato, 1996) Hunt, Lynette Anne
This thesis introduces a class of multivariate mixture models that includes latent class models and mixtures of multivariate normal distributions as special cases. Like latent class models, these models make free use of local independence to reduce the number of parameters in the model and to lead to descriptions of clusters that are easily understood. Provision is made for the introduction of within cluster associations between the variables. Discrete, multivariate normal and location model distributions are the ‘atoms’ with which the models are built, but where more is known about the nature of the distributions in sub-populations other types of distributions could be used in place of these. We use the EM algorithm to find the maximum likelihood estimates of the model parameters, however the emphasis is less on parameter estimation than on the use of the estimated component distributions to cluster the data. We implement the approach of multivariate mixture models with a Fortran 77 program. The program is used to fit models to several data sets, including a large medical data set. Analysis of the resulting clusters shows that sensible clusters have been achieved. The thesis shows how our ability to analyse data using multivariate mixture models can be extended to include the facility to handle situations where data are missing at random in the sense of Rubin (1976). The program written for this thesis incorporates this facility. The scope of the methods proposed is illustrated by clustering several data sets.
The emergence, dynamic psychological process, and regulation of obsessive entrepreneurial passion in shaping the well-being of entrepreneurs
(Thesis, The University of Waikato, 2024) Sanoon, Fathima Fasana
Entrepreneurs are known for their deep emotional attachment and commitment to their ventures. Experiencing such intense positive emotions can paradoxically lead to obsessive entrepreneurial passion (ObEP), an uncontrollable form of passion negatively associated with well-being. Despite the negative consequences of ObEP, entrepreneurs may still develop an uncontrolled emotional bond with their businesses. While research has focused on the benefits of entrepreneurial passion, there is limited research on how obsessive passion forms and its potential effects on well-being are still a topic of debate as prior studies show mixed and inconclusive findings. As such, our overarching concern is to know why entrepreneurs develop ObEP and how it potentially shapes their entrepreneurial well-being. To examine this research question, we conducted three interrelated studies. In our first study, we examined the potential drivers of obsessive entrepreneurial passion and its impact on subjective and psychological well-being by employing a quantitative research design. We identified affective entrepreneurial commitment and perceived competitive pressure as two potential drivers of obsessive entrepreneurial passion based on the premise that passion can emerge from internal and social pressure. We found that both drivers can fuel obsessive entrepreneurial passion, which negatively mediates the relationship between affective entrepreneurial commitment and subjective and psychological well-being, as well as the relationship between perceived competitive pressure and both types of entrepreneurial well-being. In our second study, we used qualitative methods to examine the underlying psychological process between obsessive entrepreneurial passion and well-being. As obsessively passionate entrepreneurs place heightened importance on their self-worth, they tend to cognitively evaluate themselves and verify their self-worth, paying attention to their own perspectives and those close to them. Thus, such cognitive self-evaluation of entrepreneurs can explain the underlying psychological process between obsessive entrepreneurial passion and well-being outcomes. We introduced a dynamic process model to explain how the cognitive self-evaluation of obsessively passionate entrepreneurs (ObPEs) results in different well-being outcomes due to experienced discrepancies and conflicts. The model portrays four phases: the emergence of ObEP, cognitive evaluation of the self, feelings of self-discrepancies and conflicts, and well-being outcomes. In addition, we explained the detrimental side of obsessive entrepreneurial passion by highlighting the vicious cycle of passion. In our third study, we proposed a dynamic model to explain how obsessively passionate entrepreneurs can manage negative emotions triggered by stress and regulate their obsessive entrepreneurial passion to shape their well-being. Using the lens of cognitive appraisal theory, we explained that obsessively passionate entrepreneurs will appraise stress as challenges or threats depending on their goals, beliefs, and ability to access resources to cope with the negative emotions triggered by stress. We highlighted that entrepreneurs who employ approach strategies to cope with negative emotions can regulate their passion by enhancing their level of obsessive entrepreneurial passion without detriment to their well-being. However, using avoidance strategies will cause them to reduce their attachment to business, leading to reduced well-being.
Brews and blooms: Development of a novel seaweed biostimulant supporting sustainable primary industry practices
(Thesis, The University of Waikato, 2024) Robertson, Holly
With a growing global population and increasing needs for environmentally friendly food production, novel technologies and products are required to increase food production sustainably. In this regard, seaweed biostimulants are an innovative tool to improve crop growth and yield. However, seaweed biomass is typically obtained through wild harvest or collection of beach cast, with challenges around the consistency of quality and reliability of supply. Furthermore, common manufacturing methods can have issues with high chemical input, loss of potentially important compounds, and cost. Therefore, this thesis aims to develop a seaweed biostimulant utilising the cultivated seaweed Ulva stenophylloides and a novel low-input fermentation method. This research covers optimisation of fermentation parameters and detailed compositional characterisation of the resulting products (Chapter 2), and the quantification of the effect of selected ferments on growth and yield in plants in hydroponics systems (Chapter 3) and in potted soil (Chapter 4). The fermentation parameters: biomass loading, sucrose input, and incubation temperature were optimised. The initial sucrose input had the largest impact on fermentation progression and success, and was the main driver in resulting glucose content, total dissolved solids, pH, and pellicle yield. Excluding treatments with low biomass loadings, treatments with low and medium sucrose inputs reached completion and treatments with high sucrose inputs did not. As indicated by residual glucose, high biomass loadings provided valuable nutrients for microbial growth and high incubation temperatures were optimal for microbial growth. A range of nutrients were extracted from the seaweed biomass, but concentrations were insufficient as a sole nutrient source for plants based on chemical analyses. High biomass loadings were the main driver in the yield of protein and the sulfated polysaccharide ulvan, which both may modulate gene expression and induce metabolic changes in plants. High incubation temperature was the main driver for the yield of the auxin phenylacetic acid and indicates the production of other possible plant growth stimulating microbial biochemicals at high temperatures. Of the four ferments selected for further testing by ferment progression and chemical composition, ferment four (high biomass loading, mid-range sucrose loading, and high incubation temperature) was the best performing biostimulant tested on mung bean seedlings in hydroponics; at a 1 % (v/v) dose, plant fresh and dry weight were increased by 15 and 16 %, respectively, and the most root growth was generated. An auxin-like effect was not detected at any biostimulant dose. At a 1 % dose, an interactive effect with fertiliser was demonstrated in tomato seedling root number. A 2 % dose of biostimulant had adverse impacts on root growth over multiple root growth assays. When applied to potted tomato plants, inconclusive results were obtained in growth and yield due to sub-optimal application volumes and growing conditions that require further method development and retesting. Overall, this thesis advances knowledge in seaweed biostimulant manufacturing utilising U. stenophylloides with a fermentation production method. These results warrant further investigation into refinement of plant assays and growing conditions, the composition of the ferments through metabolomics and microbial identification, and the biostimulant effects on soil.
Exploring school governance in the context of local values and political influences in Lalitpur, Nepal: A narrative inquiry
(Thesis, The University of Waikato, 2024) Adhikari, Devendra
Nepal is a surreal land of stunning Himalayas, Eastern mystics, and human civilisation rich in culture, traditions, and architecture. In the country, Hindu values have been predominant in shaping people's lives, including respect for schooling education. People are keen to manage schooling education through community effort by joining School Management Committees. After the implementation of Nepal’s 2015 Constitution, public schools came under the jurisdiction and management of local governments. As a local in Lalitpur, Nepal, a Hindu believer, and a former public-school teacher and administrative assistant, I became interested in researching how people’s local values and the influence of politics build public school governance. My curiosity was further driven by the literature review related to school governance in Nepal where I found limited research and scholarship of areas such as the adoption of Hindu cultural values in school governance in secular Nepal, and the exercise of power to bring about positive reforms in school management. I formulated the research questions: What cultural and social values of groups and communities in Lalitpur encourage working for school governance? How do political influences shape group and community involvement in school governance in Lalitpur? For my methodology, I choose narrative research, which lies within a social constructionist worldview whereby social reality is conceived as the co-creation of human relations and interactions. I used in-depth interviews and observations of participant engagement related to school governance, during which I interviewed 43 participants involved in school-communities and local governments in Lalitpur. These schools were situated in three local government units in urban, semi-urban, and rural areas with diverse geographies and socio-cultural settings. I developed a method of thematic analysis to interpret the participants’ stories by referencing Localism-Eastern Philosophy and New Public Management-Global Governance theories. I found that Hinduism connected Nepali communities and schools through religious sentiments and made the school environments sacred and peaceful. People’s culture of care prepared the foundation for establishing and developing schools in Nepali communities. This caring culture has been passed on as a philanthropic value to the present generation, which aligns with the karma theory in Hinduism. Concerning the political influences in school governance, exercise of power has brought knowledgeable people into SMCs to contribute to the managerial reforms and has facilitated decentralised school governance through local governments. Findings show that locals with conservative values and some stakeholders in schools have misused political authority to take benefits and hinder the growth of school education. Decentralised education governance is a new practice in Nepal, and in 2025 the country is in a federal transition stage. New education policies are being developed, and my research findings support the establishment of policies that incorporate people’s values and the exercise of political authority and power.
Unveiling the layers of educational reform: A critical realist analysis of the ideation, development and enactment of the Philippine professional standards for teachers policy
(Thesis, The University of Waikato, 2025-03-10) Macam, Alea
This study investigates changes in teacher professionalism in the Philippines in response to globalising education policies, with a particular focus on the impact of the 2017 Philippine Professional Standards for Teachers (PPST) policy introduced under the conditions of official development assistance. With the technical and financial support of the government of Australia, this policy introduces clear indicators of professional competence that challenge traditional views of teacher professionalism and redefine teacher quality. Anchored by the ontological and epistemological foundations of critical theory and critical realism, and the theoretical and methodological framework of the Critical, Cultural Political Economy of Education (Dale & Robertson, 2015), this study explores the underlying mechanisms that have shaped the ideation, development and enactment of the professional standards policy and its impact on teacher professionalism. Based on interviews with policymakers, Department of Education (DepEd) officers, a public school district supervisor, school heads and teachers, the findings of the study indicate the emergence of idealised professionalism, a term used to describe how the context and policymaking process of the professional standards policy was heavily influenced by broader economic, political, and cultural globalisation. However, this idealised professionalism remains primarily a theoretical construct that is not grounded in the actual realities of teaching in the Philippines. The introduction of the policy has resulted in ongoing tension between state regulation and teachers’ professional autonomy. This tension is further complicated by the fact that policy enactment is not always consistent across different schools and jurisdictions, with various cultural practices and contextual socio-economic factors shaping teachers’ agentic responses. Ironically, the institutionalisation of clear expectations for teachers embodied in idealised professionalism has led to teaching practices characterised by complexity rather than certainty. This study makes a contribution to the continuing debate over the role of official development assistance in driving education policies that not only perpetuate neoliberal and neocolonial practices but also fail to align with the local context of aid-receiving countries. It prompts critical reflection on whose interests are ultimately served by externally induced official development assistance project reforms in developing countries. The study recommends redirecting official development assistance towards areas of government where its benefits would be maximised, such as institutional building and capacity development, rather than project-based reforms. Additionally, establishment of a mechanism for local school stakeholders and the local community to actively participate in national policymaking could help ensure that policies are appropriate and relevant to teachers. Lastly, future studies could re-narrativise the globalisation story by concentrating on local contexts and using them as the vantage point from which to better understand the modernisation of education.
Matriarchal legacy: Intergenerational research empowering st’at’imc women through nxekmenlhkálha múta7 nt’kamenlhk’álha (st’at’imc laws and way of life)
(Thesis, The University of Waikato, 2025-03-09) Letterlough, Roxane
This thesis explores how physical literacy, which is defined here as the physical quadrant in the St’at’imc medicine wheel, mitigates trauma and promotes healing for St’at’imc matriarchs and survivors of the Canadian residential school system; it does this by highlighting stories of resilience, resistance, and finding strength in unexpected places. Initially, the study aimed to document the healing journey of twenty Indigenous residential school survivors through sport. However, the Covid-19 pandemic in 2020 and the re-discovery of the 215+ Le Estcwicwéy̓ (“the Missing”) Indigenous children at the Kamloops Indian Residential School in 2021 re-traumatized potential participants. In response to these events and ethical considerations, the research shifted focus to the Nxekmenlhkálha múta7 Nt’ákmenlhk’alha (St’at’imc laws and way of life), narratives of survivance, and intergenerational healing through research. As a matriarch of the Ts’al’alh band from the St’at’imc Nation, my narrative intertwines with those of three St’at’imc matriarchs and residential school survivors. Utilizing Indigenous story work and narrative inquiry, the study amplifies our lived experiences, emphasizing survivance rather than sport and showcasing the resilience and endurance of Indigenous women through Nxekmenlhkálha múta7 Nt’ákmenlhk’alha. This thesis represents a personal and collective journey through family and community knowledge. It demonstrates the integration of intergenerational research with my own family, including my aunties, and my children. Through an Indigenous worldview, the research reveals the strengths of children as they grow, providing them opportunities to enhance their skills and explore their culture. The study offers a space of cultural resurgence within a colonial system, promoting healing and resilience among the St’at’imc people.
Use of high-rate filamentous algal ponds for primary municipal wastewater treatment
(Thesis, The University of Waikato, 2024) Novak, Indira
High-rate filamentous algal pond (HRFAP) systems offer a promising alternative to conventional municipal wastewater treatment. Research on selecting filamentous algal species for municipal wastewater bioremediation is currently limited. Chapter 2 introduces a screening protocol aimed at identifying robust cultivars suitable for HRFAP monoculture systems. Evaluating eleven cultivars under local seasonal ambient and extreme conditions played a crucial role in cultivar selection. Based on their consistent biomass productivity and bioremediation performance across ambient and extreme conditions, Klebsormidium sp. (KLEB B), Stigeoclonium sp. (STIG A) and Ulothrix sp. were identified as target cultivars for nutrient bioremediation of primary municipal wastewater. The identification of target cultivars has previously been based on laboratory conditions, which are insufficient for practical applications. Chapter 3 assessed the biomass productivity and nutrient bioremediation performance of three cultivars - Klebsormidium flaccidum, Oedogonium calcareum, and Oedogonium sp. – in outdoor HRFAP mesocosms. K. flaccidum had the highest biomass productivity and bioremediation performance, while O. calcareum had complete die-off. Competition experiments at varying stocking densities highlighted K. flaccidum dominance at lower densities (0.25 and 0.5 g FW L-1), positioning it as the preferred cultivar for nutrient bioremediation in primary municipal wastewater within HRFAP systems. Effective management of operational parameters is crucial for optimising wastewater treatment in HRFAP systems. Therefore, in Chapter 4 the effects of hydraulic retention time (HRT), stocking density, and harvest frequency on the growth and nutrient bioremediation performance of K. flaccidum in primary municipal wastewater in outdoor HRFAPs were examined during summer and winter. Seasonal conditions impacted biomass productivity, which was 48.3% higher in summer compared to winter. A HRT of 4 days was optimal for both seasons based on bioremediation of total ammoniacal-nitrogen (TAN). Lower stocking densities of 0.25 and 0.5 g FW L-1 demonstrated enhanced bioremediation efficiency, while higher densities were preferable during slower growth periods to mitigate potential toxicity risks from primary wastewater. Harvest frequencies of two, four and six days did not significantly affect nutrient removal rates across different treatments and seasons. These results highlight the importance of seasonal optimisation of HRFAP systems to maximise biomass production and nutrient bioremediation. Wastewater treatment plants (WWTPs) are major sources of per- and polyfluoroalkyl substances (PFAS) pollution entering the environment. Certain algal species have demonstrated the ability to bioaccumulate PFAS compounds, indicating their potential for removing PFAS from wastewater. Therefore, in Chapter 5 a laboratory study was conducted to assess the ability of K. flaccidum to reduce concentrations of PFAS and PFAS precursors in primary municipal wastewater under two HRTs. K. flaccidum maintained stable productivity in the wastewater. Removal rates of PFAS and PFAS precursors, however, varied considerably. Specifically, reductions were observed in three individual PFAS and in all measured PFAS precursors present in the wastewater. Despite these reductions, PFAS was not detected in the algal biomass of K. flaccidum, making it suitable for a range of biomass applications provided it remains free of other contaminants. Overall, this thesis has demonstrated that HRFAP systems are an effective alternative treatment for nutrient reduction in primary municipal wastewater. Application of the screening protocol to select target species, and seasonal optimisation of HRFAP operating parameters will enable more consistent and effective year-round nutrient bioremediation and algal biomass productivity to be achieved.
Multi-Level process integration of heat pumps in a non-continuous processing site
(Thesis, The University of Waikato, 2024) Klinac, Elsa
Industrial process heat demands contribute significantly to New Zealand’s greenhouse gas emissions. With a global push towards decarbonization, including New Zealand’s Climate Change Response Amendment Act 2019, there is a need for methods and technologies that can be applied to replace industrial fossil fuel boiler use. With an increasing range of renewable energy sources, electrification provides a promising alternative to fossil fuel use; however, it is also critical to reduce process heat demands where possible. This can be done through the reuse of industrial waste heat via direct heat exchange, thermal storage, or heat pump installations. Existing Heat Integration methods provide a means of identifying waste heat recovery opportunities; however, these methods are typically aimed at steady state industries. In New Zealand, many industries operate in a non-continuous manner, creating challenges in the accurate application of these existing Heat Integration methods. This thesis presents a multi-level process integration method for heat pump and thermal storage retrofit on non-continuous industrial processing sites. This method aims to address several gaps in current Heat Integration methodology through the novel amalgamation of several tools discussed in four main chapters: (1) A multi-level heat pump integration tool is developed that sequentially identifies heat pump opportunities to both upgrade waste heat for reuse, and shift remaining waste process heat towards more favorable temperature ranges, (2) A multi steady state time slice investigation develops a tool for selecting appropriate time slice sizes to accurately represent variable, non-continuous industrial sites, (3) a multi steady state thermal storage identification tool is developed by applying the previously identified time slices to existing heat integration methods with an aim to further buffer fluctuations in heat demand, and optimize the thermal loads on the previously identified heat pump opportunities. The tools are combined into a final method and applied to a meat processing case study site that is representative of the variable, non-continuous industries that dominate the food sector in New Zealand. In this case study, hourly time slices were used to identify multiple successive heat pump opportunities including a 1.9 MW MVR that recompresses waste steam from the rendering dryers with a COP of 10, and a central 1.5 MW heat pump that supplies heat at 70°C to the site ring main with a COP of 3.4. In addition, it was found that the 90°C heat pump, already installed on the case study site, would have the potential to increase utilization on the case study site if the two other heat pump opportunities identified were implemented. Thermal storage opportunities were also identified that can be used to buffer heat demands on the 70°C heat pump opportunity, thereby allowing the heat pump to be resized to 1.04 MW in comparison to the initially hypothesized 1.5 MW, reducing both capital and operational costs of the heat pump. This amalgamated method provides novel Total Site Heat Integration additions, which when compared to conventional heat integration methods, provide more accurate and more useful heat pump decarbonization strategies for non-continuous industrial sites, ultimately aiding in industrial decarbonization.
Optimal decision trees via search: A reinforcement learning framework
(Thesis, The University of Waikato, 2024) Chaouki, Ayman
Decision Trees are one of the most popular models in Machine Learning because of their interpretability, which is especially noticeable for Decision Trees with few splits (or decision rules), a property that is called sparsity. Interpretable models are highly valued in domains where decisions carry substantial ramifications such as health-care and the criminal justice system. For this reason, seeking optimal sparse Decision Trees constitutes a fundamental problem in Interpretable Machine Learning, and a large research effort has been devoted to solving this problem. Due to the NP-Hard difficulty of the problem, greedy heuristic methods such as C4.5 and CART have been favoured historically, and while fast and scalable, these methods remain unsatisfactory because they forgo the sparsity portion of the problem. In fact, they often lead to suboptimal and overly complex Decision Trees. Nevertheless, many algorithms have been developed in the literature to address the sparsity problem, with recent breakthroughs leveraging Dynamic Programming (DP) and Branch & Bound (B&B) techniques, and causing a paradigm shift from traditional Mathematical Programming to search algorithms. However, most of the proposed DP and B&B methods follow a Depth-First-Search (DFS) strategy, which, while attractive due to its storage-economy capacity, is inefficient because of its uninformative nature. Moreover, DFS necessitates the definition of a maximum depth hyperparameter a priori, and its inefficiency becomes a limiting factor when considering large maximum depths. These concerns were partially addressed with Best-First-Search (BFS) strategies. BFS is appealing because it prunes the search space more aggressively without losing the optimality guarantee, thus enabling it to find the optimal solution faster than DFS. Moreover, BFS does not necessitate fixing a maximum depth hyperparameter, it can run on infinite depth, which is an important advantage that allows practitioners to focus tuning efforts on other hyperparameters. However, these advantages come at the expense of higher memory consumption than DFS. To alleviate this issue, the search strategies of BFS methods have to be formulated as efficiently as possible, in other words, they need to find the optimal solution as quickly as possible. The reason being to tip the balance of their advantages-drawbacks more towards their advantages, outweighing their high memory consumption issue. The current BFS methods can be improved substantially by reconsidering the sparsity problem under a framework that benefits from its structural properties. Our main contribution in this thesis addresses this concern within a Reinforcement Learning framework. Our BFS algorithm, Branches, benefits from an AO*-type search strategy, which, coupled with our pruning bound we call Purification Bound and several other heuristic considerations, focuses the search on relevant regions of the search space while maintaining the optimality guarantee. This enables Branches to find optimal sparse Decision Trees faster than the state of the art, and as a result alleviate the memory burden that weighs on BFS approaches. We analyse the computational complexity of Branches theoretically by deriving an upper bound on the number of branch evaluations it performs before terminating, and we show this result to be superior to similar analyses from the literature. These findings are further validated through a series of extensive experiments showing Branches to significantly advance the state of the art in terms of number of iterations, runtime, anytime behaviour and scalability potential. This work lays the foundations for future work that can further improve the scalability of these methods. In addition to this work, we also study the online setting where a data stream is observed rather than a fixed dataset. Unlike the batch setting, the literature on optimal sparse Decision Trees in is scarce for Online Learning. Most approaches adapt greedy heuristics to handling data streams through statistical estimates, hence inheriting their suboptimality issues. On this front, we develop three Monte Carlo Tree Search (MCTS) algorithms with asymptotic optimality guarantees, and we show that they can successfully retrieve the optimal solution in situations where the state of the art methods are practically guaranteed to fail. Furthermore, we adapt Branches to the online setting inducing Online-Branches, an algorithm that satisfies finite-time optimality guarantees rather than asymptotic ones. Our experiments show Online-Branches to outperform our previously developed MCTS methods. Our work on the online setting has the potential to draw more research attention to the problem of seeking optimal sparse Decision Trees when given a data stream. It also lays a solid foundation for these future works through several discussions about the potential issues that arise due to the hypotheses of Online Learning and our proposed solutions.
Access to primary music education in Aotearoa New Zealand
(Thesis, The University of Waikato, 2024) Wrathall, Jade
Music is a compulsory subject in the New Zealand Curriculum, intended for every child. Despite this, the literature illustrates inconsistent provision and enactment of music education in Aotearoa New Zealand, suggesting that some children are unable to access the full curriculum. While this situation has been attributed to a range of factors, there are significant gaps in the literature, making it difficult to determine how children’s access to music education is enabled and constrained by these factors. To understand the provision and enactment of music education, case studies were conducted in three different primary and intermediate schools in New Zealand. Informed by critical realism, a range of data collection methods were used, including semi-structured interviews, surveys, focus groups, observations, documents, and field notes. Participants were principals, members of senior leadership teams, generalist, specialist, and itinerant teachers, in addition to private contractors, children and their parents. Data were thematically analysed, revealing the intricacies of how the policy technologies of neoliberalism operate in schools. To understand generative mechanisms that impact children’s access to music education, a deeper layer of analysis was undertaken using Pierre Bourdieu’s (2018) theoretical concepts of capital and habitus. These analytical tools provided the opportunity to carefully examine the intersectionality of neoliberalism and social class. The findings of this study demonstrate how neoliberalism has reinforced a hierarchy of subjects in the curriculum, which positions music as an extracurricular activity that is either omitted, sidelined, or enacted for social objectives. Participation and success in music education are also informed by social class, with the subject being used as a tool by some parents to advantage their children and develop cultural capital. Nevertheless, this study also revealed that music education is not universally valued by the middle class, thus challenging widely held assumptions about the relationship between music and social class. These findings highlight the importance of context, in particular the role of school structure, teacher agency, and the pressures of managerialism and marketisation. This contributes to a broader understanding of policy enactment, and how the enactment of music education is influenced by the neoliberal policy regime. The study concludes that children are not given equal access to music education and that substantive change needs to occur. Implications are discussed at national and local levels, examining the role of policy alongside the roles of principals, teachers, and parents, all of whom have the agency to make change. Implications for international contexts are also considered, reinforcing the complexity of policy enactment and how children’s access to the full curriculum cannot be solved through policy alone.
Development of sustainable composites from treated harakeke (New Zealand flax) fibre and poly(lactic) acid
(Thesis, The University of Waikato, 2025) Akindoyo, John O.
The building and construction sector consumes large volume of materials, it generates enormous amounts of solid wastes, and it is responsible for about 40% of annual global CO2 emissions. So, sustainable biodegradable, recyclable or renewable materials such as polymer-based materials are seen as potential substitutes to their non-renewable, non-environmentally friendly counterparts. Poly (lactic acid) (PLA) is a polymer produced from renewable sources, thereby supporting sustainability. The use of PLA is sometimes limited by its inherent brittleness, and insufficient mechanical strength when used alone. The brittleness of PLA may be reduced by toughening it with rubbery additives, while its strength can be improved through reinforcement with materials such as natural fibres. In this thesis, fibres extracted from harakeke (Phormium tenax), otherwise called New Zealand flax is used as reinforcement in PLA composites. The fibre properties were modified to facilitate processability, improve its compatibility with PLA, and to enhance its reinforcing ability by removing components such as lignin and hemicellulose which are detrimental to the mechanical and thermal performance of the composite. Different methods such as chemical treatment with alkali solutions, mechanical processing, and enzymatic treatment were explored to modify the harakeke fibre. In addition, polybutylene succinate (PBS) was blended with PLA, followed by reactive compatibilization of the reinforced PLA/PBS blend with dicumyl peroxide (DCP), with the aim of improving the toughness of the composite. The results show that harakeke fibre is a good reinforcement for PLA, as it increased the composite strength from 62±1.02 MPa to 82±0.98 MPa. In addition, it was found that PLA/PBS blends can be reactively compatibilized and reinforced concurrently, thereby supporting the production of composites with improved mechanical, thermal, and thermomechanical performance. Generally, the results show that enzymatic treatment could serve as a more sustainable environmentally friendly route to fibre treatment as it obviates a chemical processing route and supports recyclability and reusability. Likewise, the combination of mechanical processing with enzymatic treatment has great potential for producing large scale environmentally friendly and good quality fibres, suitable for composites.
A multifaceted analysis of diurnal streamflow patterns through the application of advanced analytical tools
(Thesis, The University of Waikato, 2024) Sarwar, Muhammad Waqas
Understanding the complex dynamics of water flow within a catchment is fundamental to effective water resource management. This understanding involves robust knowledge of the catchment's hydrological and physiographical features. It requires a profound grasp of the spatiotemporal variability in a catchment's climatic and hydrological patterns. Within this context, this thesis started with a comprehensive review of the historical and current literature on diurnal fluctuations in groundwater. The review touched upon several different aspects of the phenomenon, ranging from discussing the mechanisms of the origin of these signals, their role in the catchment's water balance, their link with groundwater and with the transpiration activities of the vegetation, and in the end, the importance of studying these catchments in revealing characteristics of a catchment. Potential gaps in the analysis of diurnal fluctuations are identified by exploring the literature., which motivated the compilation of this thesis. Firstly, the relationship between diurnal fluctuation and the potential evapotranspiration of riparian plants is investigated in relation to its effect on catchment reservoir storage. A novel method of estimating evapotranspiration (ET) rates is devised by establishing a relationship between diurnal streamflow changes and the catchment's riparian source area. The method reasonably estimated riparian evapotranspiration (ET) and linked the riparian area's dynamics with the diurnal patterns in stream flow by assuming a linear relationship between saturated riparian reservoirs and outflow. This analysis provided a much-needed understanding of the behaviour of the diurnal signals in a catchment and its relationship with the physical features of the catchment. Further, this analysis deeply studied the concept of time delay associated with the transpiration activities of riparian plants and catchments' response regarding diurnal fluctuation. Additionally, the seasonal evolution of ET estimates and the time lag revealed the tight coupling between stream response and active vegetation zones, with more significant and rapid fluctuation in colder months than warmer ones. In conclusion, the method provided an elaborate understanding of the complex interplay between riparian zones, groundwater dynamics, and streamflow patterns, contributing to a more profound understanding of catchment hydrology. Another significant thesis objective was to develop advanced automated techniques for detecting and analysing diurnal fluctuations to provide fast and reliable observations of diurnal fluctuations from a large dataset. Manually identifying this scarce phenomenon in an extensive multi-year dataset is time-consuming and one of the biggest reasons for minimal, large-sample studies concerning diurnal streamflow fluctuations. This is addressed by forming an automated process of diurnal fluctuation extraction with the application of the wavelet transform. The capabilities of both types of wavelet transformation, the discrete wavelet transform (DWT) and continuous wavelet transform (CWT) are tested to reveal time-frequency information of diurnal signals. A detailed workflow is developed to choose the best wavelet for detrending a streamflow series to obtain diurnal fluctuation. The detrending performance of the DWT process is compared against the traditional time-based detrending methods like the moving average. It confirms the superiority of wavelet transform in optimal detrending of observed streamflow data series. The CWT presented many different plots and revealed exciting features in the diurnal patterns in streamflow. The CWT information is then used to develop an algorithm for extracting diurnal episodes from extensive streamflow records. The extraction process captured an adequate number of diurnal episodes, which matched well with the manual identifications. Overall, the automated technique addressed the limitations posed by manual identification and contributed significantly to the advancement of time-frequency dynamics of diurnal fluctuations. Finally, with the knowledge of diurnal fluctuation gained in the first research objective and with the capabilities of the wavelet transform, a large sample study is carried out using streamflow records from different New Zealand catchments. Various dataset sources from streamflow records, snow cover maps, and digital elevation rasters are used to calculate different catchment characteristics. The analysis showed that characteristics like catchment shape and size strongly correlate with diurnal amplitude. The diurnal lag also showed patterns of change with the catchment parameters. It is revealed that the correlation between catchment size and diurnal amplitude becomes weaker in larger catchments due to the diverse and heterogeneous nature of environmental processes within these regions. This research significantly contributes to a deeper understanding of the temporal patterns of streamflow, providing valuable insights for hydrological modeling and water resource management. By integrating field observations, advanced analytical methods, and regional context, this work advances the understanding of diurnal streamflow dynamics.
Death and homelessness on the streets of Aotearoa New Zealand: Sustaining life
(Thesis, The University of Waikato, 2024) Charvin-Fabre, Sandrine
In high-income countries, homeless people die 20 to 35 years earlier than domiciled populations. Despite this enduring reality, the issue of death inequality remains underexplored, especially in indigenous homeless contexts, facing the ongoing effects of colonisation. This study centres on the perspectives and aspirations of a Māori street homeless community, known as the “Peeps”. Its objective is twofold: to spotlight to unjust, untimely, and avoidable mortality impacting homeless communities in Aotearoa New Zealand, and to understand how life can be sustained against the adversity of street life. The thesis diverges from conventional public health approaches, which often dichotomise early deaths prevention through improved healthcare access during homelessness, and palliative care provision at the end of life of homeless people. This thesis explores “the temporal space of life prior to death”. Within that temporal realm, the omnipresent “risk of dying” that infiltrates the lives of homeless people, disrupting the linear progression toward death observed in domiciled populations, is recognised. This temporal space is understood as a zone of uncertainty and potentiality, wherein complex life-death dynamics operate, revealing broader political, societal and cultural tensions. This study encountered significant challenges, including the dearth of prior death-related research in Māori homeless contexts, and my non-Māori identity. In response, an indeterminate approach, rooted in relational ethics and complexity and systems thinking — aligned with Māori worldviews — was adopted. Part I of the thesis is conceptual and contextual. Part II invites the readers into the fragile “temporal space of life prior to death” and the cyclical research process. Cycle 1 focuses on understanding the local context of death inequality, through relational fieldwork and statistical analysis of coroners’ reports. This analysis uncovers a 30-year life expectancy disparity with domiciled populations, exacerbated by three-quarters of avoidable mortality, mainly due to chronic conditions and suicide. Subsequent cycles sustain relational fieldwork, using collaborative and critical performance ethnography. Cycle 2 reveals the Peeps’ resistance to access healthcare, rooted in experiences of transgenerational trauma and marginalisation of Māori beliefs and values in relation to death and dying within mainstream healthcare institutions. Collaboration with the Peeps leads to the co-creation of a drama, intended to initiate conversations with health professionals from the Peeps’ perspectives and aspirations, to improve the quality of care. This cycle also highlights the impact of disconnection processes with whānau (family, extended family) experienced by the Peeps. Progressing further, cycle 3 illuminates healing processes with whānau using Advance Care Planning, envisioned as a relational space, providing the Peeps with a sense of belonging, and spiritual continuity in the perspective of death and dying. In addition to shedding light on the profound death inequality that affect Māori homeless people, this thesis argues for homelessness to be recognised as “complex life-threatening conditions associated with serious-related health suffering”. Accordingly, the thesis advocates the shift toward comprehensive care, inclusive of a concurrent prevention and palliation approach over the course of homelessness, to mitigate its impact on the lives of Māori homeless people and enhance holistic wellbeing.
An efficient process to designing robotic end effectors for high value crops: Application on robotic apple fruitlet thinning
(Thesis, The University of Waikato, 2025) Jangali, Rahul
High value crops continue to rely extensively on manual labour for labour intensive and expensive tasks like harvesting and thinning. Robotics is increasingly being investigated as a solution to combat labour shortages which threaten the sustainability and growth of the horticultural sector. However, the seasonal nature of high value crops offers only a short window of a few weeks to field tests one robotic end effector per season using the conventional process. This hinders the research and development timeline of robotic end effectors. This thesis presents an efficient design process, modified from existing design methods, to overcome this limitation by capitalising the remainder of the off-season window within a year, and thus reduces the robotic end effector development time. The efficient design process starts with co-design workshops involving growers and field visits to gather requirements, understand crop physiology, and determine the specific needs for identified crop management tasks. This information guides the development of several end effector concepts. Concepts with feasible potential are selected to progress to the prototype stage, which then undergo laboratory testing and comparative evaluations during off-season. The off-season investigation can only be possible by creation of an artificial crop structure that replicates the crop's physiology and is capable of testing the prototype's core mechanism principles repetitively. This structure is also optimised with enhancements and design optimisation of the end effectors, such that field testing time can be maximised to address issue unique to field conditions. This process then allows for extensive testing of various end effectors within a single year, significantly reducing the development duration. The process prioritises the generation of multiple viable end effector concepts while integrating feedback from growers. The efficient design process was implemented to develop robotic end effectors for apple fruitlet thinning. The design requirements for thinning fruitlets to 1 or 2 fruitlets from a cluster were identified after consultation with growers and a visit to the apple orchard. Nine concepts were generated and preliminarily tested in the field and consulted with growers. Four distinct concepts were then selected: 1) cutting that cuts the stalk, 2) suction based on grasping and rotating, 3) paraboloid based on grasping and rolling, and 4) piercing end effector based on spear piercing and rotate. These concepts were further developed into fully functional end effectors for laboratory evaluation, enabled by the development of an artificial structure that allows interchangeable fruitlets of all sizes and accommodating repetitive testing of the end effectors core mechanism principles. After an iterative process of testing, optimisation, and modifications of end effectors and artificial fruitlet structures, a comparative evaluation was performed to benchmark and quantify the capability of each end effector was conducted. A computer vision system and path planning systems were developed and integrated with the end effectors to facilitate this evaluation. This shows that the vacuum suction end effector consistently reached a 100\% success rate from 90° pitch angle on single fruitlets, and also maintained this success rate at a 90° pitch angle in a fruitlet cluster in all positions, followed by cutting and paraboloid with 80\% success rate on a single fruitlet. In contrast, the spear piercing mechanism consistently under performed and was excluded from the field testing. The field test in apple orchards under real world conditions indicated that the suction end effector achieved the highest success rate, reaching 70\%, followed by cutting end effector with 44\% and paraboloid with 26\%, showing trends consistent with lab evaluations. The primary causes of failure are positioning errors and occlusion. Thus, the efficient design process developed the suitable suction end effector to be integrated with the overall robotic platform for further development within a single year, compared to a minimum of two years using a conventional process.

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