http://bura.brunel.ac.uk/handle/2438/210 2026-06-05T01:37:23Z http://bura.brunel.ac.uk/handle/2438/33356 Title: Towards an Adaptable Architecture for Digital Twin (AADT) Authors: Nwogu, Chukwudi Abstract: A Digital twin (DT) is a virtual replica of a physical object, which has the capability of integrating with a virtual object, such that they exchange data and use the data exchanged to improve each other. It is a confluence of Industry 4.0 technological innovations, such as big data, artificial intelligence, modelling and simulation, Internet of things, optimisation techniques, cyber-physical systems, amongst others; the blend of these technologies fused together for the development of a DT is driven by its use case. A DT has enormous potential, and there is a consensus among the industry, academia and governments that it is one of the most pivotal technologies in Industry 4.0 era that will play a major role in shaping the society. This widely acknowledged notion about DT has not translated into a joint effort to standardise it. As a result, there exists neither a generally accepted definition nor architecture for digital twin. The lack of standard definition, framework or architecture for DT may have a negative impact on the wider adoption and development of DT. The state-of-the-art in DT architecture, for instance, reveals that most of the architectures are designed for specific domains and/or technologies and have components that are named in such a manner that it is difficult to identify commonality in purpose and functionalities. To contribute to the taxonomy of DT architectural components, this study proposes an adaptable architecture for DT (AADT), which is developed based on design science research (DSR) principles. AADT directly addresses the architectural chaos inherited from the growth era of the digital architectural development by establishing standard components traceable to digital twin definitions, requirements, and mandatory functionalities. Rather than proposing yet another domain-specific architecture, AADT provides a systematic process for deriving architectures from requirements, enabling consistent yet flexible implementations. To support the implementation of digital twins, this research develops an implementation framework for digital twin (IFDT) that is a confluence of software development lifecycle and principles of project controls. IFDT consists of a stage gate within every lifecycle phase, which ensures that a digital twin development project is subject to business case viability test and stakeholders’ approval as it progresses from one lifecycle phase to another. AADT is evaluated with the guidance of framework for evaluating design science (FEDS) and ISO Standard 9126. The evaluation of AADT results in the development of a taxonomy of architectural adaptiveness for digital twin systems. The taxonomy organises structural, behavioural, functional and quality adaptiveness into a coherent analytical framework; and therefore, serves as both a conceptual contribution and a practical guide for evaluating future digital twin architectures. In summary, this research, contributes to the taxonomy of digital twin architectural components; develops a technology-agnostic digital twin architecture that can adapt to the requirements of disparate use cases from a wide range of domains; proposes an implementation framework for digital twin; and develops a taxonomy of architectural adaptiveness of digital twin systems. Description: This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London 2025-01-01T00:00:00Z http://bura.brunel.ac.uk/handle/2438/33181 Title: User information security behaviour in sub-Saharan Africa: A case of Ghana from an extended protection motivation perspective Authors: Baba, Abdul-Malik Abstract: Personal computer users are increasingly becoming the prime targets of cybercriminals. With the standing of the individual user as the “weakest link” in the information security chain, compounded by noncompliance with security protocols, and the assumption that they are solely responsible for their online safety, maintaining the protection of the information security of the individual computer user also known as personal computer security is thus a necessary part of overall information security. Protection Motivation Theory (PMT) has been extensively applied to explain how users behave regarding information security. Despite the above progress, several opportunities remain for enhancing our grasp of information security behaviour within the personal computing context. First and foremost, a primary gap seems to be the lack of studies concerning PMT, concerning how home computer and mobile device users approach information security behaviour. Whilst the current research acknowledges the contributions of studies that have explored this subject matter through the lens of PMT in various settings, there seems to be a lack of exploration in non-Western contexts where factors such as inadequate infrastructure, unconventional usage patterns, and IT identities prevalent in those regions. In addition, to the above, past PMT studies have also explored factors influencing user information security behaviour in this domain of research, however, the impact of perceived severity in shaping security intention is not yet fully understood. Additionally, the literature underscores the importance of investigating how factors such as security routines impacts security behaviour. In that regard, addressing these gaps in the literature is vital, as implementing security solutions designed in developed nations, without accounting for the local context, may prove to be ineffective. The present study seeks to explore how individuals in Ghana (a sub-Saharan country) protect their personal computers from information security breach based on the framework of PMT. By utilising a mixed method approach specifically an explanatory sequential mixed method design, 632 individual personal computer users consisting of home computer and mobile device users were investigated using surveys and focus groups. Collated quantitative data was meticulously analysed using Partial Least Squares Structural Equation Modelling (PLS-SEM) whilst NVivo was employed for the qualitative data analysis. The results demonstrate the crucial role of IT-identity in shaping an individual information security behavioural choice through threat and coping mechanisms of PMT, including security habit. Most of the threat and coping components of PMT significantly influence security intention. However, it was evident that there is no significant difference between home computer users and mobile device users regarding the determinants of their security behaviour. The overall sample attitudes towards information security were consistent across device types. Beyond the substantive findings, this study contributes theoretically to the academic discourse within circles on user information security behaviour research by introducing the concept of IT-identity as a factor that influences the cognitive processes of PMT, including the formation of security habits. It also adds to list of limited number of existing studies that have applied an explanatory sequential mixed-methods approach to this area of research (using a novel dataset) which has traditionally been explored through quantitative methods. Practically, it offers insights for various stakeholders across the sub-Saharan African region such as practitioners in the field and those responsible for designing security controls and training programs by recommending the implementation of a holistic IT-identity-PMT model. Description: This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London 2025-01-01T00:00:00Z http://bura.brunel.ac.uk/handle/2438/32953 Title: Artificial Intelligence & Human-Computer Interaction: The development and deployment of emotionally intelligent, LLM-augmented conversational agent software, utilising generative AI to improve pedagogical and educational management processes Authors: Yusuf, Habeebullah Abstract: Background: Viva voce examinations, a form of performance-based assessment (PBA), are valued for their ability to elicit deep insights into student understanding and oral articulation. However, they are often associated with challenges such as increased student anxiety, examiner inconsistency and high teacher workload. While artificial intelligence (AI) has seen broad adoption in education, its application in oral assessments remains limited and underexplored. Objectives: This research investigates the use of emotionally responsive AI conversational agents to address key challenges in formative viva assessments. It aims to develop two such agents; AIvaluate (a teacher-mediated agent) and AIvaluate2 (a fully autonomous agent), and evaluate their impact on student anxiety, teacher burden, assessment quality and student experience. Methods: The research follows a Design Science Research (DSR) methodology and employs the Rapid Application Development (RAD) framework for iterative prototyping. Four empirical studies were conducted in an education setting using a mixed-methods approach. Data collection methods included real-time emotional self-reporting, System Usability Scale (SUS), feedback quality scoring, grade comparisons, surveys and semi-structured interviews. Quantitative data was analysed using statistical methods such as paired-sample comparisons and TOST equivalence testing. Qualitative data was subjected to reflexive thematic analysis. Results: Findings suggest that AIvaluate successfully reduced student anxiety and teacher workload during assessments. AIvaluate2 enhanced perceptions of assessment credibility, fairness and usability, contributing to a more emotionally supportive and consistent student experience. However, certain limitations, such as the absence of human-like empathy and rapport were noted in AI-led formats. Contributions: This thesis contributes: 1. A conceptual framework for categorising pedagogical AI conversational agents. 2. Empirical evidence supporting the educational utility of LLM-augmented AI conversational agents in oral assessments. 3. Two validated AI software artefacts (AIvaluate and AIvaluate2) designed for formative viva use. 4. Insights into the role of emotional responsiveness and usability in AI-led assessment environments. Conclusion: The study advances the application of AI in education by demonstrating how emotionally intelligent conversational agents can reduce affective and operational barriers in formative oral assessments. It offers practical, scalable tools for AI-enabled pedagogy with implications for further and higher education contexts. Description: This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London 2025-01-01T00:00:00Z http://bura.brunel.ac.uk/handle/2438/32758 Title: A novel approach to automating context-driven alternative text generation through purposeful games Authors: Droutsas, Nikolaos Abstract: Accessibility of the Web is a pervasive issue, owing to the persistence of accessibility barriers (e.g., poor navigation, lack of/unsuitable alternative text (alt text), complex web forms), with significant impact on users with disabilities. Alt text barriers in particular, are some of the most prevalent web accessibility barriers affecting a wide range of media and are underpinned by a lack of understanding and guidelines on what constitutes suitable alt text. Past work has shown that the ‘context in which the image is used in’ is ironclad for suitability yet loosely defined. Whilst there is a need to automate alt text generation, current solutions disregard context in alt text and are lacklustre with regard to suitability. In this research, an empirical exploratory study that investigates the views of web content creators and visually impaired users on suitability is conducted to bridge the functional gap between experiences and best available practice. The first definition of ‘Alt Text Context’ is proposed providing a systematic way to assess when alt text is necessary and what it should convey. Further, the first crowdsourcing game for context-driven alt text authorship and evaluation—TagALTlong—is presented. TagALTlong’s design is informed by relevant literature, empirical qualitative insights and the proposed definition of context in alt text. Following an empirical user study, 125 non-expert players were recruited to play TagALTlong over a six-week period, resulting in 1208 authored and 1836 rated alt text descriptions, respectively. The resulting dataset was used to fine-tune and train an AI model for automated alt text generation to assess whether average human-level alt text quality can be approximated whilst automating the process. Results indicated the improved performance of the model that was fine-tuned and trained on the GWAP-generated dataset compared to pure image processing, subsequently demonstrating the value of the dataset. Description: This thesis was submitted for the award of Doctor of Philosophy and was awarded by Brunel University London 2026-01-01T00:00:00Z