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A framework for Go/No-Go decisions in high-tech R&D
No full textNew product development (NPD) failure rates range from 40% (Cooper, 2019) to 90% (Kim et al., 2016), so firms must allocate resources effectively, including abandoning failing projects if necessary. However, when to abandon is often unclear, so portfolio managers risk commitment escalation (Eliens et al., 2018) and overinvesting. This study explored the research question: How should firms evaluate whether to continue or abandon projects in high-tech R&D? A dual approach was taken: First, to gain foundational insights, an innovative AI-assisted literature review method was developed and used to create a novel R&D decision-making framework. Second, to test the key concepts of the framework and illustrate its application, an agent-based simulation (Sulis & Taveter, 2022) compared the performance of the framework against risk-based and ROI-based approaches in a 1000-project portfolio. The framework outperformed the other strategies in simulations and emphasised the importance of gatekeeper independence, negotiating clear criteria up front and using formal decision gates. The simulation results also suggested actionable guidance for practitioners: For a feasibility phase to add value, it should cost less than 30% of the project budget and significantly improve cost estimates.
Theoretical contribution: This study integrated key NPD decision theories from real options, behavioural decision-making, and portfolio management and developed a novel decision-making framework while exemplifying the use of AI to enable rapid, scalable research. It then demonstrated that decision gates outperform ROI- and risk-based approaches in simulation.
Practical contribution: For R&D portfolio managers, the study provides a structured decision-making approach and guidance for sizing feasibility studies. For researchers, it provides a methodology for accelerating and scaling literature reviews
Investigation of variations in the saturated hydraulic conductivity of sand and the influencing factors in the laboratory
No full textThe most critical hydraulic property of soil is the saturated hydraulic conductivity (Ks) of its matrix. Accurate determination of Ks is vital for understanding and simulating flow and transport phenomena. Hydrologists require accurate estimations of soil moisture content and retention to better discern rainfall distribution between runoff and infiltration; agronomists similarly rely on this data to inform crop yield models and formulate appropriate irrigation timetables. A diverse range of methodologies currently exists to determine the Ks, with the constant head test in the laboratory being a common approach. Traditionally, it is presumed that the Ks values obtained from both field and laboratory assessments remain constant. In addition, Ks is considered as a constant in various applications, such as solute transport modelling and surface water as well as groundwater simulations.
Given that soils can undergo saturation and desaturation they can be subjected to gradual and/or rapid changes in the hydraulic head, and thus the Ks of the soil will be affected. Consequently, any changes in Ks will affect the hydraulic properties of the soil. Therefore, to fully understand the hydraulic behaviour of a soil requires investigating the changes in Ks during short and long timeframes.
A primary objective of this study was to systematically investigate the changes that could occur in Ks during short-term and long-term constant head tests. Two soil columns were prepared and subjected to continuous constant head tests for a duration exceeding 50 days The hydraulic heads were increased gradually in a similar way as for a constant head test, with the only difference being that the hydraulic heads were increased every 5 to 7 days. The outcomes reveal that Ks exhibits negligible variations over short intervals, showing minor daily fluctuations. However, the long-term variations highlight significant shifts in Ks, with a maximum decrease in value of approximately 90% from the onset of the experiments, followed by intermittent brief periods of slight increase. These findings challenge the notion of Ks as a constant value over time. Moreover, a comparative analysis of soil properties before and after the tests indicates notable modifications in the sample characteristics. Specifically, the particle size distribution and particle density differ pre and post-experiment, with an observable migration of fine, low-density particles towards the upper section of the sample closer to the outlet, and aligned with the flow direction. This phenomenon results in an increased particle density at the lower part of the sample adjacent to the water inlet. The migration of particles is evidence of the constant head test impact on the distribution of particles. The change in the distribution of the particles pre and post experiment, caused by the standard procedure of the tests, shows that the Ks value determined in the lab through constant head tests is influenced by the tests, and might not reflect the actual Ks of the sample.
In addition, a series of short-term experiments were carried out on 10 samples that were prepared with different particle size mixtures. These mixtures featured varying proportions of fine and coarse materials to study the range of changes in the Ks in different mixtures. The hydraulic heads of the tests on these samples were systematically adjusted in ascending increments, to investigate the range of changes in Ks under low and high hydraulic heads during short-term tests. This test series revealed a distinctive 3-phase pattern exhibited by the samples: a low and relatively consistent Ks was initially observed prior to a transition through a phase change as the hydraulic head escalates, leading to a stable constant Ks under high hydraulic gradients. These observations underscore the significance of the changes of Ks during constant head tests, and show a need to consider that Ks has a range of values over time rather than being a constant value.
Determining a suitable value for Ks in the lab and field is time consuming, it can be costly, and test results can be impacted by the test conditions. For instance, in the lab, ensuring the full saturation of the samples before the tests needs determination of solid particle density, which requires a pycnometer. Moreover, due to the spatial variations in Ks, the number of samples needed to represent the typical Ks in a study area can be costly to retrieve. Similarly, to investigate the spatial variation of Ks, the field tests (slug tests, pumping tests, or tracer tests) add extra cost and time to projects. Additionally, taking soil samples or performing Ks field tests in remote areas or harsh weather conditions is an arduous task. Therefore many researchers have endeavoured to establish predictive relationships to estimate Ks accurately without relying on resource-intensive laboratory or field tests. Indirect estimation methods are generally based on easily obtainable data such as soil texture, particle size distribution, specific surface area, or porosity. These relationships are developed into pedotransfer functions and aim to provide estimations of Ks. However, the reliability of these functions remains uncertain due to discrepancies observed when comparing the results obtained using different pedotransfer functions with actual field or laboratory measurements.
To address this issue, the Ks derived from Darcy's equation for the short-term tests were compared with those computed using 7 of the most commonly used pedotransfer functions. The objective of the comparison was to evaluate the effectiveness of these equations in predicting Ks. The analysis revealed that the majority of pedotransfer functions tend to underestimate the Ks values of the soil samples. Subsequently, a novel method was employed to adjust the parameters of one of the equations, which is suitable for non-plastic sandy soils as used in the earlier experiments, by linking the equation parameters to the coefficient of uniformity and void ratio of the samples. This modification led to a more precise estimations of Ks for the range of sandy samples used in the research.
Given the inaccuracies related to the constant head tests and the impact on Ks determination (such as the disturbance in connection of drainable pores due to varying hydraulic heads, inaccuracies in reading the flow rate and sample head gradient, improper sample saturation, effect of air entrapment in the sample), it was necessary to look for improvements in determining the Ks in the soil.
Tracer tests on soil samples in the laboratory and field have been used by several researchers to estimate the soil hydraulic properties. These tests offer essential insights into site hydrogeology, aiding in the delineation of crucial factors such as natural groundwater velocity and hydraulic connectivity between neighbouring aquifers and aquitards. When coupled with groundwater flow and transport models, tracer tests can enhance the precision of defining Ks and its spatial distribution accurately.
In order to acquire soil hydraulic properties from tracer tests, a tracing element is injected into the samples, and the changes of concentration in the outflow is plotted over time. The resulting graph is called a break through curve (BTC). In order to acquire soil hydraulic properties from BTCs, advection-dispersion equations (ADE) and the models that are built upon ADE equations are widely used. The ADE links soil hydraulic properties (Ks and dispersivity coefficient) to the BTC. Trial and error is required to achieve the best fit between predicted and measured BTC which can be challenging and may require several trials to process multiple sets of BTCs.
In this study, the use of a statistical distribution, specifically the Inverse Gaussian distribution (IG), was examined for fitting BTCs obtained from 94 tracer tests utilizing sodium chloride as the tracer compound. The results of fitting the BTCs using the IG distribution revealed that solute transport in porous media could be effectively articulated using this distribution, particularly given its suitability for positively skewed data. The majority of the tracer tests fitted with the IG distribution exhibited model efficiencies exceeding 0.9 (based on Nash–Sutcliffe model efficiency coefficient), indicating a strong fit of the BTCs. A comparison of the IG method with alternative methodologies from existing research further underscored the superior fit achieved by the IG distribution in modelling BTCs.
The test series outlined in this thesis represent a significant advancement in the comprehension of saturated hydraulic conductivity within porous media. The noticeable long-term changes of Ks in the laboratory show this parameter cannot be considered as a constant, and the assumption of linearity between the hydraulic head and flow in the samples is only valid in the short-term tests. Additionally, Ks can have a range of low and high values, during rapid changes of the hydraulic head. The implications of these findings offer potential revisions to the existing approaches for integrating saturated hydraulic conductivity within equations of surface and groundwater models. Furthermore, the study highlights the viability of employing statistical methods to analyse the BTCs from tracer tests. The use of statistical methods with the tracer tests can save time and cost in the post-processing of the tracer test results
Tapuwaekiwi tapuaeharuru taiharuru te Whakatōhea toheraoa: Connecting to my iwi and reclamation of identity through endurance running grounded in iwi narratives and tikanga/culture.
No full textThis thesis explores the intersection of endurance, whakapapa, and cultural reconnection through the lens of ultra-marathon running and Te Whakatōhea tīpuna pūrākau. By weaving together personal narratives, historical contexts, and contemporary athletic practices, this research examines the role of endurance sports as a pathway for cultural revitalisation and identity reclamation among Māori athletes.
Endurance is a fundamental characteristic of Te Whakatōhea, embodied not only in the physical feats of long-distance running but also in the iwi's historical resilience through colonisation, raupatu, and cultural disconnection. This research positions ultra-marathon running as both a metaphor and a mechanism for reclaiming whakapapa, fostering well-being, and strengthening the connection between Māori athletes and te ao Māori. Drawing upon Kaupapa Māori methodology, qualitative research methods, and tikanga Māori principles, this research seeks to decolonise endurance sports by embedding iwi narratives, tikanga, and mana whenua engagement into the sport of ultra-running.
A central aim of this research is to develop a culturally grounded framework that integrates Te Whakatōhea pūrākau and tikanga into ultra-marathon events. This framework envisions a race that traverses ancestral pathways, acknowledges the whenua and mana whenua, and fosters a culturally safe environment for Māori athletes. The research questions driving this thesis examine the historical endurance of Te Whakatōhea, the impact of colonisation on Māori participation in endurance sports, and the potential for tikanga to be embedded in ultra-marathon events.
The findings of this research reveal that endurance is deeply woven into the whakapapa of Te Whakatōhea and that ultra-marathon running serves as a powerful means of reconnecting with iwi identity, whenua, and te ao Māori. Through interviews with Māori endurance athletes and an exploration of iwi narratives, this research highlights the transformative potential of culturally embedded endurance sports. Furthermore, the research identifies barriers to Māori participation in ultra-marathons, including historical disenfranchisement from traditional athletic spaces and the predominance of Pākehā worldviews in endurance sports. Addressing these barriers, this thesis proposes a tikanga-based model that seeks to attract greater Māori
participation by integrating kaupapa Māori principles into the design, organisation, and execution of ultra-marathon events.
This research is also a personal journey of endurance and reconnection, reflecting on my own whakapapa as a descendant of Te Whakatōhea and an ultra-marathon runner. Raised outside of the iwi rohe, my path of reclaiming identity through sport mirrors the broader themes of cultural endurance and revitalisation explored in this thesis. By engaging with iwi histories, participating in kaupapa Māori spaces, and embedding tikanga into my athletic practice, I have sought to bridge the gap between past and present, creating a future where Māori endurance athletes can thrive within a culturally affirming space.
Ultimately, this thesis contributes to the growing discourse on Indigenous endurance sports, cultural resilience, and decolonial approaches to athletic participation. It affirms that ultra-marathon running, when grounded in whakapapa and tikanga, has the potential to serve as a tool for cultural reconnection, healing, and identity reclamation for Māori athletes and Te Whakatōhea whānau
Corrosion segmentation on steel structures via illumination-aware preprocessing and Bayesian U²-Net
No full textSteel corrosion poses a major threat to infrastructure safety and longevity, demanding reliable
and accurate automated inspection systems. This study presents a semantic segmentation
framework that integrates an illumination-adaptive preprocessing pipeline with a Bayesianenhanced
U²-Net to address two core challenges in UAV-based corrosion inspection:
performance degradation under uneven lighting and lack of predictive uncertainty estimation.
Variational Bayesian convolutional layers are embedded in the U²-Net encoder to enhance
robustness and regularization in small-sample scenarios without relying on full probabilistic
inference. A high-resolution, pixel-level annotated dataset was developed for evaluation.
Experimental results across 45 independent training runs show that BU²-Net achieves an F1-
score of 75.088%, an IoU of 60.350%, and a recall of 71.537%, while maintaining the lowest
standard deviation across all metrics. The results confirm the method’s ability to improve
training stability and predictive consistency under visually complex conditions. This practical
integration of adaptive preprocessing and lightweight uncertainty modeling supports realworld
deployment in multimodal sensing systems for intelligent structural health monitoring
Waste to energy projects, the circular economy, and the law
No full textTwo proposals for large waste-to-energy plants are under consideration and causing a great deal of debate. They will use the most common waste-to-energy (WTE) technology, disposing of waste by burning it in an incinerator to raise steam in a boiler, to generate electricity or supply heat for industrial processes. They employ elaborate equipment to reduce air pollution. The issues raised by WTE are significant; New Zealand is among the top waste producing nations in the OECD (3.2 tonnes of waste per capita per annum), and the worst for reuse and recycling: NZ Infrastructure Commission, Rautaki Hanganga o Aotearoa 2022-2052 New Zealand Infrastructure Strategy (2022) at 98. At the same time air pollution from combustion of different kinds already has significant adverse health impacts: Gerda Kuschel and others, Health and Air Pollution in New Zealand 2016 (2022); Stats NZ, “Health Impacts of Exposure to Human-Made Air Pollution” (2023). It seems useful to ask whether the current legal and policy framework for WTE projects is satisfactory
Evaluating the impact of authenticity and person-organisation fit on work attitudes
No full textPerson-Organisation (PO) Fit and authenticity play an important role in generating positive work attitudes such as job satisfaction, organisational commitment, organisational belonging and turnover intentions. However, the question remains: which is more important? Is one more closely related to these work attitudes? As such, this study explores the correlations of PO Fit and trait and state authenticity with job satisfaction, organisational commitment, organisational belonging and turnover intentions, as well as comparing the significance of their contribution towards these work attitudes. A sample of 285 participants drawn from the general population and University of Waikato undergraduate students completed an online questionnaire examining these concepts, and the hypotheses and research questions were empirically tested using correlation and multiple regression analyses. The results found that both PO Fit and state authenticity were significant contributors to job satisfaction, organisational commitment, organisational belonging and turnover intentions. Notably, one measure of PO Fit – the Person Organisation Fit Questionnaire emerged as the most significant contributor to all our chosen work attitudes. This study is among the first to compare PO Fit and authenticity on work attitudes, enriching the existing literature and offering vital insights for organisations. Indeed, it highlights the importance of prioritising PO Fit to enhance job satisfaction, nurturing organisational commitment and belonging, and reducing turnover intentions. Future research recommendations include investigating additional components within the broader Person-Environment fit framework, such as person-supervisor, person-job, and person-group fit, to better understand their influence on work attitudes. Additionally, intervention studies are recommended to evaluate strategies aimed at enhancing PO Fit and authenticity, and to assess their impact on positive work attitudes
Using the theory of planned behaviour to predict intentions to reduce the environmental impact of travel
No full textThe use of private cars is responsible for a large amount of the world’s CO2 emissions
and the amount of pollution produced by the aviation industry is also growing at an alarming
rate. Thus, it is important to understand the factors that can lead to pro-environmental
behaviours (PEB), such as choosing more environmentally friendly options for air and car
travel. I explored whether the Theory of Planned Behaviour (TPB) variables of
environmental attitudes, subjective norms, and perceived behavioural control (PBC)
predicted individuals’ willingness to change their travel behaviour. A sample of 327
participants from New Zealand and the United States of America completed an online
questionnaire measuring TPB variables for low-, medium- and high-cost behaviours which
were defined as short, medium, and long trips by both car and plane. I hypothesised that, in
line with the A-B-C model, the TBP variables would be most predictive of intentions to
reduce the environmental impact of medium-cost behaviours, rather than low- or high-cost
behaviours. Attitudes, subjective norms, and PBC almost always significantly predicted
behavioural intention for the NZ sample, whilst only subjective norms and PBC were
significant predictors for the USA sample, however, there was no support for the low-cost
hypothesis or A-B-C model. Findings may influence and inform interventions and policy
aimed at behavioural change in different contexts and that it may be beneficial for
interventions to be tailored to specific populations based upon the strength of correlating
variables
Heritage buildings and community sense of place
No full textNew Zealand is a nation that has a significant amount of built heritage, of which there are several internationally recognised landmarks, including the Christchurch Cathedral, the Church of the Good Shepherd, and the Chateau Tongariro. These structures contribute to establishing a sense of place within a community as landmarks, gathering places, and keepers of memories and personal sentiments. Unfortunately, due to New Zealand’s recent and historic seismic activity, these landmarks, commonly constructed as unreinforced concrete or masonry, are susceptible to severe damage from earthquake-induced ground shaking. For this reason, the New Zealand government introduced the Building (Earthquake-prone Buildings) Amendment Act 2016, which presented stricter seismic strengthening regulations for vulnerable buildings (earthquake-prone buildings) to ensure better life safety outcomes for such structures. The associated costs and challenges of retrofitting heritage buildings have put many of these structures at risk of abandonment or demolition, taking their embodied heritage value with them. This research uses survey data to establish how heritage buildings develop a sense of place within a community and how the public’s perception can implicate preserving heritage buildings. Survey results indicated that people value these structures in their communities. Further, personal connections to heritage buildings or knowledge of the historical context improve the desire to preserve and restore these structures
A multifaceted analysis of diurnal streamflow patterns through the application of advanced analytical tools
No full textUnderstanding 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
Pasifika students' perceptions of using talanoa as an assessment tool in NCEA level 2 mathematics
No full textThis study explored Pasifika students’ perceptions of Talanoa as a culturally responsive assessment tool in NCEA Level 2 Mathematics, addressing the educational challenges faced by Pasifika learners within conventional Western assessment frameworks. Despite growing recognition of the need for culturally responsive teaching, limited research exists on how alternative assessment tools like Talanoa can reshape students’ engagement and outcomes in mathematics.
Using a qualitative methodology grounded in the Kakala Research Framework and employing Talanoa as both a method and research approach, data were collected from six Year 12 Pasifika students in a New Zealand secondary school. Key findings revealed that Talanoa fosters trust, enhances cultural competence, deepens understanding, builds self-confidence, and creates an engaging learning environment. Together, these elements transformed students’ attitudes, making the assessment experience more inclusive, supportive, and effective.
This study contributes to addressing systemic inequities in education by proposing culturally aligned assessment tools and offering practical solutions for a more inclusive learning environment. It highlights the potential of integrating culturally responsive practices like Talanoa to improve educational outcomes for Pasifika students, with insights that may also benefit other culturally diverse learners.
Future research could explore how Talanoa-informed frameworks can be incorporated into other subject areas, teacher training programmes, or education policies to create a wider impact on culturally responsive practices. Such studies would help determine the broader applicability of Talanoa as a holistic educational tool beyond mathematics