Doctoral Theses

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https://hdl.handle.net/10292/4

The Doctoral Theses collection contains digital copies of AUT doctoral theses deposited with the Library since 2004 and made available open access. All theses for doctorates awarded from 2007 onwards are required to be deposited in Tuwhera Open Theses unless subject to an embargo.

For theses submitted prior to 2007, open access was not mandatory, so only those theses for which the author has given consent are available in Tuwhera Open Theses. Where consent for open access has not been provided, the thesis is usually recorded in the AUT Library catalogue where the full text, if available, may be accessed with an AUT password. Other people should request an Interlibrary Loan through their library.

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3D Localization Techniques for Wireless Sensor Networks
(Auckland University of Technology, 2019) Ahmad, Tanveer
Location information is crucial for the correct interpretation of data collected through wireless sensor networks (WSNs). The de facto system for wireless localization, Global Positioning System (GPS) does not work properly in indoor environment, thus researchers are thriving to find other localization schemes for indoor WSNs. The main goal of this work is to study and design three-dimensional (3D) wireless localization schemes for indoor applications. In this thesis, a new and accurate, efficient and cost-effective algorithm, called parametric loop division (PLD) has been proposed for localizing static nodes within a WSN. In the proposed technique, reference points can help to produce new parametric points by calculating the mid points and by taking step size that falls within the network boundary. The objective of PLD scheme is to estimate the actual localization volume and find the node position in 3D space by using subdivision method. In each step, triangles are subdivided into pairs with the addition of extraordinary nodes in its control ring matrix. Parametric points are generated by using the step size and RSSI is compared with threshold value for localization. The work involves the development of novel solution which utilizes the anchor node position information to calibrate nodes with unknown target, allowing it to work even in a changing environment with increased reliability and accuracy. Subsequently, PLD is evaluated in presence of different types of noises. Firstly, the localization accuracy was tested without the addition of noise in distance measurement. Like other schemes, PLD is adversely affected by the noise, which reduces the accuracy of the system. A new framework with extended kalman filtering (EKF) is proposed to refine the nodes coordinates affected by the noise. Furthermore, an analytical framework is presented with the detailed study of lower bound of the localization accuracy. The PLD is tested for naive, Gaussian and intelligent noise. The anchor node is modelled by only using the knowledge information of coordinates to redesign the distance vertex from anchor to parametric points. Finally, we consider the mobile based localization scheme, which has become popular recently with the development of autonomous robots and unmanned aerial vehicles. We designed an extended centroid based localization system that use the weight on distance to compute the signal power. A fuzzy logic approach is adopted for computation. The design is divided in to In the first phase, RSSI is mapped to fuzzy membership function. The mobile anchor exchange beacon and measure distance using RSSI data. The target node position is computed in a circle within the sensing region for a mobile anchor node, which moves on a random walk for broadcasting beacons. RSSI and signal power is used as an input for fuzzy system. In the second phase, for accurate node positioning a perpendicular bisector is drawn from rough estimation to circle drawn previously. Like EKF, fuzzy logic works well in nonlinear estimation of target nodes locations. Localization problem is evolving with the advance of mobile technologies and this thesis contributes to the fast development of this topic. However, there are still some issued left out as future study, mainly on the effect of anchor node localization error, implementing mobile anchor in a PLD algorithm and energy-aware localization schemes in WSNs.
A 3D printed ballistic drug delivery system for wildlife administration
(Auckland University of Technology, 2019) Long, Jingjunjiao
Overpopulation of wildlife, especially in pest-prone territories, is a major ecological problem. Culling is the most effective population control approach but drug-induced contraception is also common for protected species. The administration of contraception in the wild has been restricted to conventional methods such as surgery which require capturing and handling often large numbers of incorporative or dangerous animals. This thesis proposed a new approach for wildlife contraception by utilising three-dimensional (3D) printing technology to fabricate a novel ballistic drug delivery system (BDDS) capable of remotely administering contraceptives amongst any other required drug(s). A literature review was conducted focusing on the use and application of fused deposition modelling (FDM) method of 3D printing in drug delivery (Chapter 2). In chapter 3, A ballistic projectile for short-term (seasonal) progesterone (P4)-induced contraception was developed using FDM. A sustained drug release (over five months) was achieved with the projectile providing sufficient kinetic energy to penetrate thin and medium-thickness skins. Subsequently, this projectile was modified to a multi-compartment model capable of loading and delivering multiple drugs, including anti-inflammatory dexamethasone (DEX), local anaesthetic lidocaine hydrochloride (LDC) and contraceptive levonorgestrel (LNG). The drug formulations were independently developed in the following chapters: DEX was formulated in poly (vinyl alcohol) (PVA) hydrogels, and a sustained release was achieved over one month (Chapter 4), LDC was incorporated with chitosan-pectin (CS-PEC) hydrogel and manufactured as a customised 3D printed wound dressing that released LDC in 5h (Chapter 5), LNG was incorporated within a combined system of CS microspheres and PVA hydrogels, achieving controlled release for over two years (Chapter 6). The above formulations, can be easily incorporated into a multiple-compartment projectile as a BDDS or could be used individually for other clinical applications. The new knowledge created by this thesis provide new insights into ballistic delivery to wildlife, and make a major contribution to advance the application of 3D printing technology in drug delivery.
A Discursive Dance – A Foucauldian Discourse Analysis of Caring Touch in Health Practice
(Auckland University of Technology, 2023) Power, Nicola
The act of one person touching another is an act discursively produced and, therefore, constructed as acceptable in some situations and not in others dependant on who, where, and when the touch is actioned. Challenges, therefore, have the potential to arise; particularly within the realms of health practice where acts of touch are commonplace. This study has a specific focus on caring touch. Caring touch is a form of non-verbal communication enacted between people to demonstrate compassion, support, and empathy; and is constructed by social, gender and cultural perspectives. The aim of this inquiry was to analyse the discursive constructions of caring touch in health practice. The complexity of caring touch required a methodology that recognised the presence of multiple viewpoints, values, and practices. Therefore, this study employed post-structural discourse analysis, which drew on the work of Michel Foucault and his notions of discourse, the subject, technologies, and governmentality. Semi-structured interviews with 20 practitioners recruited from nursing, paramedicine, midwifery, and medicine, provided the data for this inquiry. Analysis of the data demonstrated an interplay of multiple discourses that made caring touch, as an act incorporated into health practice, challenging. Findings from this study showed constructions of caring touch were at times juxtaposed across, and within, the four health disciplines. Although scopes of practice meant participants were able to legitimately cross boundaries of interpersonal space to employ their specific acts of care, caring touch was made more complex as it was not a ‘necessary’ part of practice. At times, caring touch was constructed as part of professional identity where it was normalised as complementary to other tasks undertaken, and an important aspect of care. Conversely, caring touch was sometimes constructed as an ‘extra’, an unnecessary part of professional practice that restricted time for diagnosis and treatment. Evident for most participants were uncertainties pertaining to what acts of caring touch were doable and, what were not, in terms of their professional practice, situating these participants at a discursive impasse. Similarly, there was an underlying unknowingness that pointed to wider constructs of touching another person that dominated practice. Contradictions in the constructions of caring touch co-existed for the participants. This created tensions and unease; particularly for the male practitioners, where an undercurrent that discourses of gender and the sexualisation of touch knowingly or otherwise, influenced their acts of caring touch. Irrespective of how the male practitioners experienced or understood caring touch, there was a hesitation regarding how acts of caring touch would be interpreted. Acts of caring touch, therefore, became too complex to negotiate and touch interactions with patients were limited. In summary, caring touch is a social construction that permeates the working lives of many health practitioners where acts of caring touch are both taken up or marginalised according to the discourses that dominate practice for the individual. The findings from this study contribute to the body of knowledge in a topic of significant complexity. This thesis opens up possibilities for the production and circulation of alternative discourses that may broaden the potential for patient wellbeing; and specifically, may create a space for health practitioners to navigate opportunities for caring touch.
A High Time Resolution Study of the Radio Emission from Pulsars
(Auckland University of Technology, 2023) Prymak, Nataliya
This thesis reports on the foundation, establishment, development, and initial outcomes of the large-scale pulsar radio emission statistics survey (PRESS), which was initiated and carried out during this PhD project. The research started by developing and testing novel methods of analysing single-pulse polarisation fluctuation, based on the theory developed by van Straten (2009) and van Straten and Tiburzi (2017). For this pioneering effort, we used an existing set of single-pulse polarisation observations recorded at the Arecibo radio telescope (Hankins & Rankin, 2010). By analysing the covariances between the Stokes parameters in these archival data, we discovered several rare polarisation phenomena. In particular, the Arecibo data included a highly sensitive observation of the first- discovered pulsar, PSR B1919+21 (also known as PSR J1921+2153), which allowed us to perform a direct comparison between our statistical approach and more traditional methods of analysis. For example, principal component analysis of the matrix of covariances between the Stokes parameters led to the discovery of an unexpected oblate spheroidal distribution of the polarisation vector. This was confirmed using a scatter plot in the Poincaré sphere, which revealed a toroidal distribution of polarisation vectors centered near the origin of the Poincaré sphere. Further temporal and spectral analysis of the polarization fluctuations led us to discover that the polarisation vectors cycle around the toroidal axis of revolution synchronously with the drifting sub-pulse modulation of the total intensity, an effect that has been observed in only one other study (Edwards, 2004). Prior to launching the observation campaign for PRESS, we experimentally verified a novel equation that describes sensitivity to the variance of modulated radio emission using single pulse observations of PSR J0437-4715 (Osłowski et al., 2014). After a brief description of the observing campaign that was carried out using Murriyang, the 64-m Parkes radio telescope, we present an overview of the current state of the PRESS data processing pipeline, including encountered challenges and solutions implemented during pipeline development. This part of the thesis primarily describes our efforts to validate the quality of the outputs produced by the data processing pipeline and the challenges presented by Radio Frequency Interference. Finally, we report on the preliminary results of a single-pulse statistical analysis of PRESS observations of PSR J1921+2153. The techniques, tools, and data presented in this thesis create new opportunities for future single pulse studies of radio pulsar emission.
A Modular Multilevel Converter that Integrates Artificial Intelligence for Fault Locating and Protection
(Auckland University of Technology, 2023) Inwumoh, Jude
High Voltage Direct Current (HVDC) transmission has provided a variety of possibilities for renewable energy resources and regional substations to boost power supply reliability and operational flexibility. To accommodate this development and improve power system performance, the Modular Multilevel Converter (MMC) has been comprehensively adopted as a potential converter solution for HVDC applications due to its modularity and scalability. However, challenges such as cost, power losses, faults, regulating AC circulating current and energy balance can hamper their practical applications and deployment, especially in controlling and protecting the MMC-HVDC grid. Furthermore, the most crucial and challenging control issue lies in the inability of the converter to offer DC fault protection, since conventional control schemes always struggle to achieve converter energy balance and DC Fault Ride Through (DC-FRT) capability due to the unbalanced system parameters. Reviewing this research gap, a novel control structure has been proposed in this thesis ensuring a proper dynamic response, balancing the arm and leg internal energies, minimising the oscillations in DC current, offering DC-FRT capability and supporting Static Synchronous Compensator (STATCOM) of AC loads. Moreover, the proposed control scheme is integrated in a novel MMC topology as a means of providing primary protection against fault. Since a DC fault can cause a severe and sudden rise in the converter’s arm current, it will be more detrimental to the Half Bridge (HB) MMCs that lack DC Fault Ride-Through (DC-FRT) capability. Several fault-tolerant converters with DC-FRT capability are surveyed. However, the cost of implementation, power losses, complexity, and controllability of the converters limit their applications. To cut down on the cost and the number of electronic devices, a cascaded hybrid design and an Alternate Arm Converter (AAC) were suggested in literature. However, they require a large number of capacitors and inductors to filter the distortions created by the switching of the MMC’s IGBTs. Furthermore, they cannot provide reactive power compensation in the event of a DC short circuit since all their MMC arms will stop conducting as they clear the fault. Therefore, this thesis proposes a novel single-clamped hybrid-arm MMC topology with STATCOM and DC-FRT capability at reduced losses, cost, and number of electronic devices. Implementing the proposed control system and the novel converter topology could be limited to non-permanent faults. For a DC overcurrent fault that lasts for an extended period (a permanent fault), the converter cannot sustain the grid with reactive power compensation for that long. Thus, the MMC-HVDC systems would struggle to ensure power supply reliability, thereby shutting down the entire HVDC network. As a result, a reliable backup fault location approach is paramount for grid protection and restoration during such a fault impact. The conventional fault location methods still struggle with setting manual protective thresholds and, they are vulnerable to fault resistance and noise. In most cases, they require a communication channel for the fault data which could potentially lead to signal delay and data loss. In Multi-Terminal (MT) HVDC network, locating a fault is challenging due to the poor selectivity and sensitivity of the traditional location schemes. Therefore, this thesis proposes a robust fault location approach based on Bidirectional Long-Short Term Memory (Bi-LSTM) using deep learning. The proposed method is a simplified decision-making model that uses fault features from only one end of the network to eliminate the need for a communication channel. The proposed Bi-LSTM fault location scheme is accurate; however, it is critical to locate faults in a sufficiently fast and more accurate manner. This thesis also presented a faster and robust location scheme to minimize the outage time and costs associated with faults on HVDC transmission lines. Therefore, a novel fault location technique is proposed to integrate support vector machine (SVM) algorithms to reduce the time needed to locate faults through fault classification. After classification, Gaussian Process Regression (GPR) is used for location identification.
A Multilevel Investigation on How Hospitality Employees’ Career Commitment Changes Over Time
(Auckland University of Technology, 2023) Zhu, Dan
As working in the hospitality industry is often considered a negative career option by the latent workforce, the industry is facing labour shortages. The high turnover rate of the industry being a global concern not only indicates that hospitality workers are leaving their employers, but also implies that they are withdrawing from the industry. This PhD research project aims to contribute to the understanding of hospitality employees’ career commitment which is vital for the sustainable development of hospitality businesses and the industry but has received scant attention from researchers. Though a number of studies have uncovered the reasons for leaving the hospitality sector, there is a paucity of empirical evidence on the factors driving hospitality employees to stay in their occupational field. Even, among the limited works on this topic, the majority adopted between-person (cross-sectional) design and neglected within-person variance in career commitment and its antecedents, failing to provide evidence on whether their findings can remain valid over time. Based on vocational theories and meta-analytical reviews, the present study examines the relations of career commitment with the two important but less investigated antecedents (i.e., occupational self-efficacy and family support) using longitudinal design. This work also explores the mediation mechanism (i.e., affective organisational commitment) underlying these relationships. A review of extant literature shows that few studies have tested an integrated model of career commitment combining both antecedents and outcomes. Particularly, with respect to the consequences of career commitment, much emphasis has been placed on the organisational outcome. This study assesses the causal relation between career commitment and wellbeing to provide a better understanding of the impact of career commitment on individual outcomes. While it is widely believed that the development of a career is a life-long process and several career-related constructs (e.g., career calling) have been found to be time-varying, the temporal nature of career commitment is understudied due to lack of longitudinal data. This study fills this gap by exploring the dynamic process through which career commitment develops. This thesis also investigates whether the predictive effects of the antecedents may vary as time passes. The study adopts a positivist paradigm with a quantitative methodology. A survey research method is employed with the aim of empirically and quantitatively examining hospitality employees’ career commitment. Longitudinal data were gathered from 310 respondents working in the hospitality industry who were surveyed at three points in time, with a three-month lag between each. Statistical Package for the Social Sciences (SPSS) 26, Hierarchical Linear Modelling (HLM) 7 and Mplus 8.0 were applied to analyse data and test hypotheses. The research findings show that occupational self-efficacy and family support positively predict career commitment at both the within- and between-person levels. The results also exhibit that affective organisational commitment mediates such relations at both the within- and between-person levels. The positive time-lagged effect of career commitment on wellbeing is revealed. The research also reveals that career commitment indeed changes over time. While early-career employees display higher levels of career commitment than old-timers (employees who have relatively longer career tenure), they experience a drop in career commitment as time passes. In contrast, an increasing trajectory of change occurs in old-timers’ career commitment. The change in the magnitude of the antecedents of career commitment is also captured. This is the first work to develop and present a dynamic theoretical model for understanding the antecedents of career commitment, the psychological process concerning how it is influenced by the antecedents, as well as its effect on individual outcomes using multi-wave and multilevel research design. This is also the first study to record the developmental trajectory of career commitment and the time-varying effects of the antecedents. The contributions of the findings to the existing knowledge and their implications for practitioners are elucidated along with detailed suggestions for future studies on hospitality employees’ career development and management.
A Non-Contact Vital Signs Monitoring Approach Using FMCW mmWave Radar
(Auckland University of Technology, 2023) Singh, Anuradha
Vital signs such as heart rate (HR) and respiration rate (RR) are critical for the clinical assessment of an individual's health and have high predictive value in identifying undesired events like cardiac arrest, critical dizziness, arrhythmias, and synchronization with respiration rate. Traditional contact-based methods are limited by their reliance on accessories attached to the body, making continuous monitoring challenging in both clinical and home environments. Moreover, wearable devices may not be suitable for patients with skin allergies, burns, or infants. Microwave radar sensing, which offers superior penetration through materials and clothing, and is less affected by environmental conditions, is posited as a promising alternative for continuous, non-contact monitoring. However, extracting physiological information from radar signals presents a significant challenge, primarily because the phase changes in the received signal are highly susceptible to environmental noise and interference, particularly when measuring HR in realistic circumstances. Even the individual's body movement can substantially impact HR readings. Skin displacement from heart activity is much smaller than that caused by respiration, leading to a weaker reflected signal from heartbeats compared to respiration. Furthermore, the HR spectrum's entire frequency range contains significant noise from the second and third-order harmonics of the respiration and intermodulation products. Environmental clutter and random body movements also add to the noise in the received reflected signal, posing a considerable challenge in developing an efficient system for HR estimation. The research focuses on developing an efficient, accurate, and privacy-aware non-contact vital sign (NCVS) monitoring method using mm-wave radar technology and devising a signal processing algorithm to improve the accuracy of heart rate and respiration rate measurements. The research adopts a multi-pronged approach to achieve these goals. This includes analytical modelling of the chest wall motion due to cardiovascular activity, facilitating a nuanced understanding of trade-offs between various radar parameters. Furthermore, the study proposes using a non-linear signal analysis technique, resonance sparse spectrum decomposition (RSSD), to better capture and analyze the complex dynamics of non-stationary signals. RSSD decomposes the signal into time-varying frequency components using wavelet decomposition and sparse approximation, identifies and isolates resonant frequencies, and constructs a sparse representation of the signal. This approach offers a highly accurate and efficient method for analyzing non-stationary signals with time-varying spectral characteristics. A harmonic-based algorithm is formulated to improve the accuracy of HR measurement. Additionally, target localization, crucial for the practical deployment of radar-based NCVS systems, becomes even more challenging due to the inevitable positional changes in real-world scenarios. We introduce an automatic, real-time beam steering and beam forming algorithm for identifying target locations, which augments the signal-to-noise ratio (SNR) and enhances vital sign estimation accuracy. The effectiveness of the proposed method is evaluated through a series of experiments carried out in various realistic settings, including artificial clutter and body movements such as reading a book, drinking water, and forward and backward body movements. To mitigate the noise and interference due to these additional attributes, we optimize the Q factor selection for each dataset by modifying the RSSD algorithm parameter selection by leveraging the sub-band energy distribution leading to a more precise extraction of HR. The findings demonstrate that the proposed method effectively mitigates issues caused by unwanted clutter, manages random body motion and harmonic interference, and significantly improves HR estimation accuracy by reducing noise in the phase signal.
A Novel Blockchain-Based Incentive Mechanism to Mitigate Inequalities for Prescription Management System
(Auckland University of Technology, 2023) Khan, Arshad
The research proposes a BlockPres framework and an incentive mechanism based on blockchain technology. The aim is to encourage participation and the use of healthcare services. The integration of advanced technologies has led to the development of a smart healthcare system, which is increasingly recognized as essential in meeting the needs of today's society. The literature review identified challenges in the Prescription Management System (PMS), an essential aspect of the healthcare system. It also found that trust, affordability, and accessibility contribute to unequal access to services. Therefore, such disparities create disadvantages in different communities when accessing healthcare services. The BlockPres framework is created and introduced in this study as a solution to the issues in the prescription management system in New Zealand. It utilizes a novel incentive mechanism that rewards patients for actively participating and engaging with healthcare services. Tokens can be earned by patients whenever they participate and engage with the PMS, and spent on other healthcare services or for purchasing products. Tokens can also be transferred to others to assist them in obtaining additional healthcare services. The blockchain technology incorporated into BlockPres provides immutability, decentralization, accountability, and security features, for increasing equal access and participation by easy to use authorization and authentication for healthcare providers and patients. Moreover, BlockPres empowers the under-served by providing them control and access to their records. The researcher formulated questions and hypotheses around the problem, and the proposed solution. The study adopted and adapted Design Science Research Methodology (DSRM) to be the guiding framework for the research. DSRM consists of three primary phases: problem identification, solution design, and evaluation. In the problem identification phase, the study identified the issue and formulated research questions that led to the development of the BlockPres Artefact in the solution design phase. The evaluation phase of DSRM has validation to verify the proposed artefact and incentive mechanism. To answer the research questions and validate the proposed solution, an evaluation of the BlockPres artefact was completed. The evaluation involved two stages. First, a simulation was performed using the Ethereum blockchain. It tested the successful completion of transactions and the performance rates, and confirmed the efficiency and effectiveness of blockchain for a prescription management system. Secondly, based on the simulation results, a BlockPres prototype was developed to evaluate the solution and incentive mechanism. The results showed that the artefact improved motivation and community engagement, trust, and perceptions of PMS and health services. However, it is recommended that industry experts test the artefact in future work to validate its effectiveness in a live environment.
A Nudging ERA? Evaluating the Effects of a Legislative Default on Union Membership Decisions to Inform the Suitability of Nudge Theory in Employment Relations.
(Auckland University of Technology, 2023) Treanor, Damian
Union decline has been the most significant issue in employment relations for the past 30 years and how to revitalise unionism has been a significant focus of academia and policymakers. In New Zealand, the political zeitgeist favours soft regulation, and eschews hard regulation, of employee union membership decisions but to date, these soft regulations have been ineffective in rejuvenating unionism in New Zealand. A new approach that has the potential to be an effective soft regulatory tool is nudge theory. Nudges have a strong potential to promote union membership decisions whilst preserving employees’ freedom of association, but the potential of nudges in employment relations policy has not been explored. This thesis explores the potential of nudge theory as a method to promote unionism by exploring the impact, and effectiveness of a new regulation that is analogous to a nudge, the requirement under s62a of the Employment Relations Act 2000 for employers to pass-on employee information to the union by default. A mixed- method of both qualitative and quantitative data collection methods was used including survey data, semi-structured interviews and form completion data. A multi-industry case study methodology was used to ensure a breadth of data and limiting section-specific factors. It was found that nudges are effective at promoting employees to speak to a union and had a small but positive impact on union membership outcomes. Most employees were comfortable with their information being passed on to the union, including those who intended to join but had not, and employees who did not intend to join but did not mind the prospect of being contacted. Negative outcomes were identified; these recommend nudges should be utilised with caution and that many employees were uncomfortable with the nudge. This thesis explores the potential of nudges to promote union membership, demonstrates that it has strong potential to be an effective tool, and make recommendations on how nudges should be utilised to maximise positive outcome and minimise negative outcomes
A philosophical critique of the best interests test as a criterion for decision making in law and clinical practice
(Auckland University of Technology, 2007-11-27) Godbold, Rosemary P
The best interest test is the legal mechanism which governs decision making on behalf of adults who lack the capacity to make their own health care treatment decisions. The test has attracted considerable criticism from health professionals, academics, judges and lawyers for being ill-defined and non-specific. The question of what is meant by 'best interests' remains largely unanswered. As a consequence, the test gives medical and legal decision makers considerable discretion to apply their personal value judgements within supposedly value-free philosophical frameworks - unreasoned and opaque decision making processes are the inevitable result. Because of the dominance of supposedly value-free philosophical frameworks, the place of values in decision making is not always fully understood. Reasoning is not possible without values, which stem from our emotions and passions, our upbringing, our religion, our cultures, our processes of socialisation and from our life experiences. Values help us make sense of our daily lives. I argue that law - like any other social institution - is essentially a human, values based construct. I put forward a theory of values-based law which argues for the recognition that laws, rules and conventions are based on, and contain, individual values. Currently, medical and legal decision makers justify grave decisions on behalf of society's most vulnerable citizens without revealing, or even acknowledging the values which drive and inform their decisions. Any opportunities to scrutinise or debate the values driving decisions are lost. Ultimately, values-based law argues that values underlying best interest determinations must be exposed to facilitate honest, transparent and fulsome decision making on behalf of adults who lack capacity. By applying the theory of values-based law, supposedly value-free decision making processes are exposed as insufficient to facilitate fulsome, honest and transparent legal reasoning.
A Teenage Gothic American Dream: A Critical Exploration of Adolescence, Time, and Nature in Post-2010 Gothic-Horror Television Series
(Auckland University of Technology, 2023) Speakman, Blair
This Doctor of Philosophy explores adolescence, time, and nature in connection to the construction of identity in American culture in the twenty-first century in three post-2010 Gothic-horror television series, Riverdale (2017-), Teen Wolf (2011-2017), and The Chilling Adventures of Sabrina (2018-2020). The Gothic emerged as a mode of narrative representation in the Eighteenth century and has become omnipresent in a variety of popular culture texts including television. Following the proliferation of cable channels and streaming-video-on-demand services such as Netflix, the presence of Gothic-horror on television has exploded into what is, arguably, a new ‘Golden Age’. A number of post-2010 Gothic-horror television series feature ensemble casts of teenage protagonists and explore the trials and tribulations of adolescence. However, there is still limited scholarly attention on the representation of adolescent characters and cultural conceptions of time and nature in these television series. To critically examine adolescence, time, and nature in the selected television series, the project’s research questions are: 1) ‘What is the relationship between the representation of adolescent characters, time, and nature in Gothic-horror television series and the ongoing construction of identity in American culture in the twenty-first century?’; 2) ‘What do contemporary Gothic-horror television series reveal through their engagement with notions of time and their depiction of dreams, visions, and themes of nature versus urban?’ ; and 3) ‘What do contemporary Gothic-horror television series reveal through its engagement with notions of time and its depiction of dreams, visions, and themes of nature versus urban’. Thematic analysis and textual analysis are used to discuss adolescence, nature, and time in relation to a range of academic fields including the Gothic and television studies. The project explores how through the adolescent characters in Riverdale, Teen Wolf, and The Chilling Adventures of Sabrina, these series disrupt culturally constructed notions of nature and time. Specifically, the study uncovers the ways in which characters often experience distorted realities including dreams/nightmares or temporal interruptions in time. Remarkably, the project also reveals that the chosen series are preoccupied with the EcoGothic and the transformative nature of the forest setting, as well as horror of the decay of the American Dream.
The academic journeys of returning postgraduate students: perceptions of appropriate educational provision for their web-based learning
(Auckland University of Technology, 2016) Angove, Nancy Christine
This thesis makes an original contribution to research into the challenges facing mature postgraduate students returning to web-based study. The distinct challenges this cohort faces distinguish it from other student groups, but little research has been conducted on the transition process these students undergo in adapting to the online environment. In particular, the thesis focuses on the academic literacy needs of these students. It seeks to capture both the challenges this cohort encounters and also the enabling strategies that facilitate their studies. Using a grounded theory approach, the study explores tutor, support staff and student perspectives regarding these challenges and strategies. In this way the thesis addresses a gap in the existing literature. Data collection involved focus groups, semi-structured interviews, and a document and records review. Three parallel streams - tutors, support staff and students from five New Zealand universities - participated. Findings revealed continuing tension between the traditional view of academic literacy practices as autonomous and transparent and the contemporary perspective of writing as socially situated practice. The findings, which are in agreement with the literature, confirm that there is a distinct gap between undergraduate and postgraduate studies, and particularly in the area of web-based studies. The students need to find ways to manage this gap. The thesis identifies four main areas of challenge faced by students in adjusting to the academic environment: managing the gap though induction, developing self-management, developing critical reading, and developing critical writing. Student experiences demonstrated that face to face induction was an enabling strategy which established expectations, began socialisation processes, and familiarised students with the web-based mode. Self- management, along with induction, established the foundation for student learning. Students spoke of creating a study environment, being a self- starter, and employing time management strategies from course commencement. Support, both in their home environment and from the institution, was important, along with the confidence to proactively seek assistance. Reading was often perceived in terms of reading to write, with a focus on required readings. Some students described their initial experiences as being at the level of reading for understanding, rather than reading critically; consequently strategies which encouraged reading for a purpose, combined with interaction on discussion forums (DFs), were valued. Writing for assessment included both traditional and applied genres and digital text formats, which differed according to context. Writing was often framed by an emphasis on structure, having a sequenced argument, demonstrating an acceptable tone, integrating readings, and staying within the ideas expressed in the literature. When writing, some students felt that new viewpoints, even if supported by the literature, were not encouraged. Recommendations arising from the findings include making the detail and purpose of course activities explicit, providing specific links to institutional web-based support, ensuring the availability of targeted assistance, and responding to individual needs at induction. Further research into the perspectives of other non-mainstream cohorts in the web-based environment would add to knowledge in the area. Research that focuses on the challenges of the online environment from course coordinators’ perspectives would also inform teaching and learning. This study has indicated that there is insufficient cooperation between various support services and postgraduate academic staff at New Zealand universities, and this area requires further investigation. These are issues of great concern in a rapidly changing educational environment. .
Accountability towards enabling commercialisation of research in public tertiary education institutions
(Auckland University of Technology, 2010) Narayan, Anil Kumar
Commercialisation of research has increasingly become a desirable activity for many tertiary education institutions (TEIs) across the globe. There is now widespread recognition by all sectors of society that TEIs engagement with research commercialisation will help drive a nation’s innovation system and contribute to the needs of the economy and society. However, in recent times, the growing accountability agenda for research commercialisation has raised important challenges for TEIs. There are increasing concerns that TEIs have failed to achieve the desired results of research commercialisation (for e.g. Dahlstrand, 2008; Goldfarb & Henrekson, 2003; Salmi, 2009) as has been anticipated by both public and private entities. Predictably, a broad range of stakeholders are increasingly asking TEIs to justify the use of public resources and to provide a more thorough account of their research outcomes (Fielen, 2007; Gauthier, 2004). There also remains considerable uncertainty amongst TEIs as to the mechanisms by which they are able to leverage the intellectual abilities of their research staff, particularly, given the complex and long-term nature of the commercialisation process. This study draws on the theoretical perspectives of new institutional theory (NIT) and uses three New Zealand TEIs as case studies to explore how public TEIs identify and render accountability in the process of enabling commercialisation of research. Data was collected using a mixed method approach of interviews and a broad range of secondary documents and archival records that covered the period 2002-2010. The constructive-interpretive research strategy permitted the simultaneous selection, inductive analysis, and interpretation of contextual data in order to construct emergent themes arising from the real-life context of commercialisation. The study highlights a number of important findings. First, TEIs are embedded in a complex network of institutionalised relationships with normative and cultural-cognitive obligations towards enabling commercialisation of research. These relationships require careful management to help shape TEIs responses to select and use appropriate accountability mechanisms to enable and enhance commercialisation. Second, while research commercialisation has become legitimised in terms of nation building activities, the commercialisation agenda has been potentially undermined by a strong performance based research funding (PBRF) culture. As a consequence, commercialisation remains a marginal activity as TEIs strongly view accountability for research in terms of funding levels. In the main, TEIs do not consider returning value in terms of commercialisation as an obligatory part of accepting funding to support basic research. Finally, new public management (NPM) accountability with a focus on bureaucratic compliance fails to recognise the uncertain, complex, and long-term nature of the research commercialisation process. To avoid NPM tensions, TEIs have ‘decoupled’ from the technical requirements to render accountability for commercialisation performance. Consequently, this is causing legitimating behaviour in TEIs and in fact, accountability for research commercialisation seems to have become a ‘representational faithfulness’ to the rhetoric in the TEIs strategic documents. This research makes important contribution to theory, policy and practice. In regards to theory, the current research contributes through the application of new institutional theory (NIT) to two demanding fields of research and this is the first time NIT has been applied to examine public sector accountability within the context of enabling academic research commercialisation. A conceptual model of accountability has been developed identifying accountability obligations, management of accountability expectations, and discharge of accountability obligations. While most studies are ex post, this framework provides a three stage model to help examine ex ante and ex post accountability. In relation to practice, this study identifies the gap between rhetoric and reality of accountability that seems to have become a characteristic of the accountability environment within which public TEIs operate. While the rhetoric in strategic documents helps legitimise research commercialisation, the accountability practices of commercialisation are not thoroughly embedded, widely accepted, and effective as the rhetoric suggests. The study provides a model for enabling commercialisation of research that helps inform practice from early stage development of a research culture, to setting clear research targets in terms of PBRF goals, to finally establishing commercialisation initiatives. In relation to policy, this study identifies notable tensions between academic research and commercialisation. As a consequence, government needs to become more explicit in articulating its policy on research commercialisation so that TEIs move beyond identifying accountability simply in terms of PBRF goals. The study demonstrates that government policy needs to provide incentives to ensure that academic research and research commercialisation become two important roles of TEIs that complement and reinforce each other. The PBRF policy needs to be redeveloped to recognise research in terms of economic contributions and value adding activities leading to commercial outcomes. There is an urgent need for both government and TEIs to frame policy that encourages the development of a research culture within TEIs that remains sufficiently focussed on successful research commercialisation.
Accounting and Accountability of Australian and New Zealand Social Businesses
(Auckland University of Technology, 2022) Zeng, Sheri
Social business is receiving increased attention, due to its role in pursuing a social mission through self-financing business models, rather than relying on philanthropy to survive (Manetti, 2014). Following on from the hybrid nature of social businesses, they should not only be accountable for blended value creation but should also be accountable for reporting their financial and social performance to multiple stakeholders. It is therefore necessary for social businesses to demonstrate how they discharged their accountability, created social impacts, pursued their missions, and become more self-sustainable (White, 2018). However, how social businesses discharge accountability and measure their social impact remains unclear (Jeffrey & Perkins, 2013), as there is no common impact measurement method and no established reporting guide. Doherty, Haugh and Lyon (2014, p.14) state that “there is a need for a greater understanding of how social businesses account for their performance”. Therefore, this research aims to explore accountability and social impact measurement in the context of Australia and New Zealand social businesses. To achieve this purpose, this research relies on accountability theory and the concept of blended value as a theoretical lens to explore how Australian and New Zealand social businesses discharge their accountability and measure their impacts through reporting and disclosure, as well as what challenges or barriers social businesses face in discharging accountability and measuring impacts. Content analysis and semi-structured interviews are adopted in this research to answer the research questions. The researcher utilises content analysis to analyse the extent and comprehensiveness of the information disclosure. Nineteen semi-structured interviews are conducted to explore how managers understand accountability and social impact, and their perspectives on the challenges they face in discharging accountability and measuring impacts. The findings of this research show that many sample companies did not provide comprehensive information, but a few did well. Significant differences observed in the extent and quality of disclosure among social businesses and between the five accountability categories. Specifically, social businesses mainly focused on reporting information about accountability for resource allocation, accountability for process and accountability for outputs. However, the information available was limited regarding financial performance, social outcomes and impacts. The interview data reveals that differing views on accountability and definition of social impact and the challenges social businesses faced which resulted in a different extent and quality of information reporting. This research contributes to the existing literature in several ways. First, this research contributes to a holistic understanding of the accountability logic in social businesses, by introducing the concept of blended value (Emerson, 2003). Second, based on the prior literature, this research proposes the accountability categories and items to investigate how social businesses discharge their accountabilities and measure their impacts through reporting and disclosure. Third, this research provides detailed analysis of how 40 Australian and New Zealand social businesses measure their impact through reporting and disclosure. Last, the researcher interviewed 19 managers and founders of the sample businesses to understand their perceptions on accountability and social impact measurement. In doing so, this research provides a richer analysis of social business accountability and social impact measurement. This research also contributes to practice. First, the researcher proposes a concise reporting framework for social businesses based on the limited body of social business research examining the accountability fulfilment and impact measurement. Second, the findings will prove beneficial to standard setters and regulators. As social business has not yet become a recognised business category, some institutions in Australia and New Zealand focus on developing a structured reporting framework and measurement method that can be applied in social businesses. Therefore, standard setters and regulators would gain important insights from the findings of this research to develop the reporting guidance and measurement method for social businesses.
Accruals: signalling or misleading? Evidence from New Zealand
(Auckland University of Technology, 2008-02-26) Koerniadi, Hardjo
Studies on earnings management usually hypothesise that managers manage accruals opportunistically. Few studies however, argue that managers can also use accruals to improve the value relevance of reported earnings to help investors better assess the firm's operating performance. While substantial evidence on managers' opportunistic behaviour on accruals has been documented in the literature, empirical evidence on the informativeness of accruals is scarce and inconclusive. The purpose of this thesis is to examine whether managers use accruals to communicate private information regarding the firm's operating performance, or as reported in the literature, use them for their own benefit. This thesis finds that on average, firms reporting high earnings accompanied by high accruals have significantly negative subsequent period stock returns suggesting that these firms manage their accounting earnings. Focusing on stock dividend issues as an incentive to opportunistically increase accruals, the results are found to be consistent with the earnings management hypothesis. Stock dividend issuing firms are reported to significantly increase accruals in the issue year followed by poor earnings and stock price performances in the subsequent year. Moreover, discretionary accruals of the issuing firms are negatively correlated with both future earnings and abnormal stock returns. This evidence attempts to complement the earnings management literature. The analysis on the incentive to decrease accruals related to share repurchases, however, does not provide sufficient evidence to suggest that managers use their discretion to decrease accruals. To investigate the hypothesis that managers use accruals to convey information regarding their firm's future profitability, this thesis employs the contemporaneous earnings and dividend announcements as the research setting. This choice was made to increase the likelihood of detecting the use of accruals as private information communication while simultaneously mitigating the likelihood of the opportunistic income smoothing hypothesis to explain the results. The evidence strongly indicates that managers use both accruals and dividend increases as their private information communication regarding their firm's future profitability. Dividend increasing firms report positive accruals which are positively correlated with future profitability. This finding contributes to the literature by providing evidence on the accrual signalling hypothesis. Overall, the results of this thesis suggest that, depending on the incentives, managers can use the discretion accorded under the Generally Accepted Accounting Principles (GAAP) in estimating accounting accrual, either to manage accruals opportunistically or to help investors better assess the firms' operating performance.
Acculturation experiences and workplace cultural diversity dynamics: a comparative study of Chinese, Indian and Eastern European migrants in New Zealand
(Auckland University of Technology, 2014) McIntyre, Nancy Chee Fun
As a migrant-receiving nation, New Zealand’s workplace is culturally diverse. Given the culturally diverse backgrounds of the migrants from Asia and Eastern Europe, this research investigated how Chinese, Indian and Eastern European migrants in New Zealand interact with their co-workers, and how these encounters and dynamics shape their learning and behaviour over time. The investigation answers the two research questions: (i) What are the acculturative dynamics , encountered by migrants in their New Zealand workplaces? (ii) How have these encounters and migrants’ responses informed, and impacted on, individual learning and behaviour in the New Zealand workplace? Multi-cultural workforce dynamics have important repercussions for management, staff, and their organisation. Interpersonal dynamics invariably generate learning experiences for all parties. This study aimed to make a significant contribution by understanding how migrants interpret, adjust and apply their learning in the workplace. The thesis provides managers with an informed understanding of the dynamics of a diverse workforce, with implications for maximising the uniqueness and advantages of that workforce. Numerous studies have examined diversity in the workplace. But very little research has been done on the experiences of Chinese, Indian and Eastern European migrants in New Zealand, and none has compared and contrasted their experiences and learning from an organisational-behaviour perspective. This research makes an important academic contribution by adding a new dimension to the existing scholarly literature on the acculturative processes of migrants from an organisational-behaviour perspective within a workplace environment, enriched by providing perspectives from managers, supervisors and/or work colleagues of migrant participants.
An Accurate and Robust Indoor Localization System Using Deep Learning and Passive Infrared Sensors
(Auckland University of Technology, 2022) Ngamakeur, Kan
Internet of Things (IoT) has evolved significantly over the past decade, enabling a wide range of applications for indoor environments in different fields such as smart building, healthcare, and energy management. A person's location is crucial information in providing their core services. Thus, indoor localization is a fundamental component of these applications. Different technologies are available for indoor localization. However, video camera technology and wearable devices are not always practical in all situations. A video camera may cause privacy issues. People may not cooperate to hold or wear the devices because they forget or feel uncomfortable. As a result, Passive Infrared (PIR) sensors are employed for indoor localization to mitigate these issues. The advantages of PIR sensors include their low power consumption, cost-effectiveness, and low electromagnetic interference. In addition, their analog or voltage outputs can provide fine-grained information regarding a person’s location such as phase and amplitude. Thus, it is possible to leverage analog outputs to estimate a person’s location. However, utilizing PIR analog outputs is not simple due to their ambiguity and a lack of PIR sensor specification. This research focuses on addressing the challenges of indoor localization based on PIR analog signal including the design of a PIR sensor node, single person localization, and multi-person localization. Firstly, this thesis proposes a novel design of a PIR sensor node and a prototype is developed to collect data. Secondly, this thesis proposes a deep learning framework for a single person localization. The proposed CNN-LSTM model not only extracts features from PIR analog output automatically but also learn temporal dependencies between the extracted features. Lastly, the proposed localization framework is extended to support multi-person localization. This thesis proposes a channel separation method to generate inputs for each person. Then, deep CNN-LSTM estimates a location for each person and a mean bagging method is used to integrate multiple CNN-LSTM models for improving the accuracy of multi-person localization. A set of experiments are conducted, and the proposed localization methods can achieve good results for both single person and multi-person localization.
Accurate Three-Dimensional (3D) Measurement of Highly Specular Surfaces for Quality Control Program of Large-scaled Production Line
(Auckland University of Technology, 2022) Dawda, Arpita Rajkumar
In the production line, inspection and quality control are essential to maintain the quality of the products. It assures confidence in the manufacturer and provides satisfaction to the customer. Product inspection is an indispensable tool of the modern manufacturing process. It helps in maintaining the quality of the product and reduces manufacturing costs by eliminating scrap losses. Several non-destructive examinations (NDE), or non-destructive testing (NDT), are used to analyze materials for inherent flaws such as fractures, dents or cracks. Same as the manufacturing process, the inspection process should also be automatic. Machine vision emerged as an important new technique for industrial inspection and quality control in the early 1980s. It is proven to be an accurate and inexpensive inspection tool for high volume, labour-intensive and repetitive inspection operations in automotive and manufacturing industries. Machine vision provides the technology and methods for imaging-based automatic inspection and analysis. However, the reflective surface of the object puts some limitations on traditional methods of machine vision. Generally, the inspection of the reflective surface is performed in a dark environment, as the ambient lighting condition of the working environment makes the reflective surface look highly specular. This research mainly focuses on overcoming the limitation of traditional machine vision methods. A novel three-dimensional (3D) measuring system is developed to inspect a product with a highly specular surface accurately. This technique aims to combine the concepts of stereo vision and laser triangulation for the 3D reconstruction of the product. This method provides a simple but accurate solution to inspect the reflective surface. The main advantage of this system is that it works robustly even in the presence of ambient light. The thesis briefly explains the effect of background on the accuracy of the inspection. Also, a thorough comparison of red and blue light lasers in terms of accuracy is described. In addition, the difficulties induced by the nature of the surface in ambient lighting conditions are evaluated. An algorithm is invented to overcome these difficulties. Along with accurate measurements, it is also essential to detect defects such as dents, bumps, cracks, and scratches present in a product. As these defects are palpable and are not visible by the camera, it is tough to detect them using vision-based inspection techniques in ambient lighting conditions. This thesis focuses on three types of defects: Dents, Bumps, and Scratches. With the proposed 3D measurement system, we can detect the defects of size 0.02mm accurately. Artificial intelligence (AI) has many applications in the production industries. One of the applications is to inspect the products for defects. However, AI is not used to reconstruct a 3D model of the product with reflective surfaces accurately. In this research, we propose to use machine learning-based techniques for the accurate 3D reconstruction of the product. The one-dimensional (1D) data of the projected laser line is used to train machine learning (ML) and deep learning (DL) models. These models are trained to detect the projected laser line accurately in the presence of ambient light. The detected laser line plays a vital role in creating an accurate 3D model of the product. Finally, we compare different machine learning-based techniques with the abovementioned stereo-laser technique based on accuracy.
Achieving Sustainable Construction Through Construction & Demolition Waste Minimisation in Residential Building Projects
(Auckland University of Technology, 2022) Gade, Rohit
Human desires and their fulfilment through urbanisation have become a global environmental concern. In addition, the factual claims made on socio-economic and environmental benefits achieved through Construction & Demolition (C&D) waste minimisation, are yet to be fully explored. This research sought to find out the contribution of C&D waste minimisation, to Sustainable Construction. Worldwide, the Construction Industry (CI) is considered as an instrument for economic growth and employment. As an industry, construction accounted directly for 6% of global GDP. In New Zealand (NZ) the building and construction sector contribute 7% to the nation’s GDP. Further, the residential sector in NZ contributed up to half of the total construction value. The NZ CI is in a period of growth and expected to remain a significant contributor to the national construction value. However, the CI’s growth is occurring at the expense of social, environmental and economic impact on the New Zealanders. The impact has urged the need for Sustainable Construction (SC) for the NZ CI. SC is a well-known concept, which is used as a method to optimise resource consumption, minimise waste and maximise investment returns. Three key aspects of SC are social, economic and environmental. All SC aspects are independent yet interlinked. Some of the important environmental elements are resource consumption, land and water pollution, energy consumption and C&D waste. The literature finding that brought attention was C&D waste labelled as the third largest waste stream in the world, largest waste streams in Auckland and NZ. However, less interest has been shown in minimising C&D waste, especially through life cycle thinking i.e. pre-design, design, construction, refurbishment and demolition. In addition, knowledge gaps exist in the implementation of C&D waste minimisation approaches to advocate SC. The overarching aim to develop a C&D waste minimisation framework considering life cycle thinking is achieved through a mixed-method approach. This study conducted semi-structured exploratory interviews and on-site observations to achieve the research aim. A pragmatic approach was adopted for the data collection. Further, data analysis was done through multiple techniques, for example. thematic analysis, content analysis and descriptive analysis. The finding of this study provided factors influencing C&D waste, challenges in C&D waste minimisation and their remedial measures. In the pre-design stage, contractual requirements were identified as the most influencing factors and the top challenge. One of the remedies, is putting a waste minimisation clause (mandatory/voluntary) in the contractor document. Subsequently, in the design stage, the circular economy was identified as the most influencing factor and a leading challenge for CI practitioners, which needs to be addressed through client education and demand. Further, in the construction stage, waste sorting was the most influencing factor and the top challenge. Contractors need to use multiple bins on-site depending on the activities and educate site labourers through tool-box meetings to sort waste efficiently. In the refurbishment stage, environmental impact of refurbishment waste was the most influencing factor and key challenge. The remedy for this challenge was found to be the introduction of compliance for reuse. In the demolition stage 10R thinking (Refuse, Rethink, Reduce, Reuse, Repair, Relocate, Remanufacture, Repurpose, Recycle and Recover) and waste levy, were the most influential factors and top two challenges. Increase in waste levy for landfill and introduction of waste levy for C&D waste fills, was noted as a positive step towards waste minimisation. 10R thinking needs to be stimulated in the Auckland CI through: providing technical and financial guidance to innovative businesses; investing in remanufacturing and recycling infrastructure; and commercialisation of innovative waste minimisation ideas. This study proposes a waste minimisation framework and required actions from clients, contractors and policymakers and influencers to promote C&D waste minimisation. Some of the most significant actions are: • Client: Demand for eco-labelled materials and changed attitude towards second life products. • Contractors: Establish SC group and implement product stewardship scheme • Policymakers and Influencers: Support innovative businesses For efficient waste minimisation, actions from one group requires support from other two groups. For instance, if policymakers decide to fund community recycling centres, the client needs to demand sustainable materials, and contractors need to use them. The proposed waste minimisation framework attempts to promote C&D waste minimisation and serves as a guideline for practitioners and researchers to establish a link in current research areas and future trends.
Achieving Thermal Comfort Using Intelligent Windows in Buildings
(Auckland University of Technology, 2021) Pokhrel, Manoj Kumar
In temperate climatic conditions, residents often ventilate their houses naturally by opening windows. Though numerous studies have examined ventilation in buildings, few have attempted to modulate naturally ventilated spaces' thermal behaviour actively using just the windows. Maintaining a house's thermal comfort characteristics by modulating natural ventilation is particularly challenging, as accurately predicting natural ventilation is a complicated task, and the solution is not explicit. This is due to various non-linear, dynamic and unpredictable environmental and operating factors that influence natural ventilation's driving forces (wind and buoyancy). Furthermore, the potential for natural ventilation to regulate thermal behaviour using windows and its influence on convective heat transfer from indoor surfaces is also not explicit. To address this issue, this work utilised a coupled thermal and network airflow to perform a building performance evaluation. In the first instance, the work examined the potential for regulating the thermal behaviour of a single-sided naturally ventilated model house by opening or shutting a window considering the NZ climatic, building and operating conditions. The study identified significant scope for regulating the thermal behaviour by opening windows. The range improved considerably for a relatively airtight and insulated house during the summer period. However, the work realised that such thermal-airflow model’s robustness needs greater scrutiny; particularly the method for determining the indoor surface’s convective heat transfer coefficient. To scrutinise natural ventilation's influence on the heat transfer process, the research considered the case of a single-sided partly open air-filled cubicle enclosure with a heated floor (analogous to a room exposed to solar radiation). In doing this, Computational Fluid Dynamics (CFD) was used to determine a relationship to describe the heat transfer by natural convection from the floor surface. The relationship showed that the heat transfer can be expressed in terms of the Nusselt number (Nu), Rayleigh number (Ra) and window opening factor (WOF) or aspect ratio (d^'/D^' ), and expressed in the form of either Nu=0.1593.〖Ra〗^0.33.〖WOF〗^0.18 or Nu=0.17.〖Ra〗^0.33.(d^'/D^' )^0.18. The work also observed that there was a significant variation in flow fields in 3D space resulting in a non-uniform distribution of floor heat flux on the spatial spectrum. From this, it was apparent that there was a need to understand the added influence of wind conditions. Thus, the research further examined the flow in, and heat transfer from the floor of, the same enclosure developed in the CFD environment while considering the impact of outdoor wind conditions (wind speed and direction). The investigation showed that changes in the wind conditions could significantly change flow regimes and temperature distributions inside the space, leading to a significant variation in the convective heat transfer from the floor. This micro analysis of computational model deduced another relationship to estimate the heat transfer coefficient for the floor 〖(h〗_(c,floor)) of a naturally ventilated building as a function of wind speed at a meteorological height 〖(V〗_m) and direction (∅), and can be expressed as: h_(c,floor)=a+(b.V_m )+(c.∅)+(d.〖V_m〗^2 )+ (e.V_m.∅)+(f.∅^2). Hence, the robustness of the building’s thermal airflow model was improved by including these specifically deduced convective heat transfer relationships to systematically analyse the effect of buoyancy and wind. A dimensionless Archimedes Number (Ar) was used to determine the dominant effect (wind or buoyancy) causing the airflow through the opening and switch the respective heat transfer relationships for the floor. Further analysis of the dynamic simulations reconfirmed the potential of regulating thermal behaviour by actively modulating window openings. Finally, a solution for maintaining a house's thermal comfort characteristics by modulating natural ventilation required a technique that could adjust the opening area while encompassing the complexity, dynamics, and non-linearity associated with the natural ventilation driving forces and the building thermal behaviour. The work addressed this issue by applying an artificial intelligence technique – Artificial Neural Network (ANN), using a co-simulation environment of Transient System Simulation (TRNSYS) and Matrix Laboratory (MATLAB). The ANN-based model, trained using the dynamic simulations database, was used to actuate window intelligently and modulate the natural ventilation to maintain the indoor thermal comfort level during the summer months. The intelligent window actuating model helped ensure the ventilated space's thermal comfort condition for more than 90% instances during the summer period. Furthermore, the research work confirmed that expanding the ANN technique to control additional heating equipment ensured the ventilated space's thermal comfort for more than 96% instances over the year. In summary, the use of the new correlations describing the heat transfer processes in the building and ANN appear to offer a positive outlook in the development of intelligent control of actuated windows for the next generation naturally ventilated sustainable buildings. The study also provides a significant benefit to delivering a better-built environment by achieving better thermal comfort, building energy efficiency and indoor air quality.

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