SACM - Australia
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9648
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Item Restricted Identification of groundwater flow patterns and barriers in aquifers(Saudi Digital Library, 2025) Asiri, Mohammed; Shelyag, Sergiy; Miller, TonyThe use of inverse methods has been increasing in hydrology. Numerical methods can help identify groundwater barriers and flow patterns in an aquifer, which can reduce errors when comparing the exact and estimated solutions. This thesis uses the method of characteristics (MOC) to identify transmissivity T in an area of abnormal region. From Darcy’s law for steady-state groundwater flow, we start with a one-dimensional case, which helps us consider what may and may not be in the two-dimensional case. Then we use the 2D case to calculate the stream function and find that the gradient of the stream function is orthogonal to the gradient of the head, and we use this when calculating the stream function everywhere. We use MODFLOW to generate head data for the known distribution T and to estimate T under different inflow examples. MOC gives a stable solution and can help identify the area of low T without requiring smoothness of the T distribution.7 0Item Restricted The Effectiveness of Hybrid Micro-Grid System in Selected Locations in Saudi Arabia(Saudi Digital Library, 2026) ALLHIBI, HAMED; Firoz, AlamThe need for socio-economic development, industrialisation, and lifestyle advancement pro- pels rising energy demand globally. The majority of energy needs are met by fossil fuels (coal, oil, and gas), which emit significant greenhouse gas emissions, degrading the environment and accelerating the global climate impact. The greenhouse gas emission and its impact are more prominent in high energy-consuming nations like the Kingdom of Saudi Arabia, where most power is generated by fossil fuels. Although the country’s 35 million population is largely spread in major cities and towns (83%), a significant population (17%) still lives in rural and remote areas across the vast country (2.15 million square km). The power needs for most of these populations are met not by grid-connected power but by locally generated power (mainly diesel fuel). As a responsible nation, the Kingdom of Saudi Arabia has committed to the Paris Climate Agreement and adopted a plan to reduce fossil fuel use for power by gradually increasing renewable power generation, especially in remote and rural areas. The geographic location of Saudi Arabia offers the opportunity to enhance both solar and wind energy. However, the distribution of renewable energy (solar and wind) is not uniform throughout the country. Hence, the primary objective of this study is to explore the opportunity to harness renewable energy along with other types of energy, emphasising CO2 reduction and cost optimisation. The study is envisioned to develop a mathematical model of a hybrid power generation system incorporating solar, wind, and diesel energy for rural areas. This research aims to study and formulate accurate mathematical models to determine the hybrid microgrid system response for renewable energy location and allocation in rural and urban areas. A mathematical model is presented to design hybrid microgrid system based on the positioning of renewable energy resources besides the traditional resources to plan for the entire area. This new model takes into consideration demand needs and limited resources. The objective of the developed model is to minimise the emission and cost of the system while the demand is covered by using renewable energy. To quantify the power needs of the selected population, two areas along with the popu- lation—one in a rural area (Al-Gahah) and the other in an urban area (Jeddah)—have been selected. Data on household power usage have been obtained and analysed. Wind character- istics and solar irradiation data from the selected areas have also been collected. Based on collected data, the hybrid power generation mathematical model has been developed using five scenarios: a) diesel only, b) diesel and solar, c) diesel and wind, and d) diesel, solar, and wind. Initially, commercial software (HOMER) was used to predict optimal power generation for four scenarios. However, the optimised prediction did not fully address the need for local population requirements, especially the CO2 and cost together. To overcome these limita- tions, the mathematical power generation prediction model has been developed, validated by first an Excel-based model and later a Python-based model. The model validated by the case study data across four distinct scenarios, illustrate the robustness and efficacy of the model. It fulfils all constraints, determining the system configuration that achieves the de- sired function while complying with environmental and financial restrictions. The developed model is capable of predicting optimised power generation incorporating both cost and CO2 emissions. It can also be used to determine optimal power generation based only on cost or CO2 emissions. The model can be used to develop a hybrid power generation system using solar, wind, and other energy for areas in Saudi Arabia and elsewhere. The model can be used to enhance strategic, tactical, and operational planning for hybrid microgrid systems for achieving a more reliable power supply, a cleaner environment through diminished CO2 emis- sions, and reduced operational expenses for diverse microgrid and mini-grid power generation in Saudi Arabia and elsewhere.7 0Item Embargo Three Essays on Corporate Political Donations(Saudi Digital Library, 2026) Aloraini, Ali; Effiezal, Abdul Wahab; Imran, HaiderThis thesis contains three distinct but interconnected essays that examine corporate political donations and their influence on corporate behaviour among Australian publicly listed firms. In response to the ongoing debate concerning the effectiveness and implications of corporate political engagement, the study consists of three essays examining various aspects of corporate political donations to provide valuable insights into this corporate activity. The thesis attempts to determine whether firms making political donations are engaging in harmful agency behaviour or such donations serve as strategic tools for advancing legitimate business interests through stakeholder relationship management and regulatory engagement. Using datasets covering the period from 2006 to 2022 with 2,973 to 3,404 firm-year observations, the first essay examines corporate outcomes and reports that firms making political donations exhibit lower levels of cash holdings, higher leverage, and reduced investment efficiency. The second essay investigates earnings quality and reveals that political donations are associated with higher levels of earnings quality across multiple earnings management proxies. The third essay explores tax behaviour and indicates that politically active firms engage in more conservative tax planning rather than aggressive tax-avoidance strategies. These findings highlight competing theoretical explanations for corporate political engagement. The first essay supports agency theory concerns, suggesting that political donations reflect managerial opportunism that harms shareholder value. In contrast, the second and third essays validate legitimacy theory by suggesting that politically active firms, seeking to maintain societal approval and regulatory favour, improve their reporting quality and adopt responsible tax practices. Consequently, this thesis reveals a complex duality in corporate political engagement, where agency costs collaborate with legitimacy benefits. While political donations may lead to suboptimal financial decision-making, they also contribute to enhanced earnings quality and prudent tax behaviour. Firms and investors should therefore consider both potential agency issues and legitimacy advantages when evaluating corporate political activities. The first chapter provides the introduction to the thesis, discussing its motivation and structure, and offering an overall background on political connections. The second chapter explores the relationship between political donations and corporate outcomes, including cash holdings, leverage, and investment efficiency. The analysis examines multiple political donation measures and conducts additional tests, including endogeneity tests, to ensure reliable results. The third chapter investigates the association between political donations and earnings quality using multiple measures of earnings management. This study employs various political donation and earnings quality measures and performs additional tests, and endogeneity checks to verify the main findings. The fourth chapter analyses the link between political donations and tax avoidance, using different measures of political donations and tax avoidance, and conducting further robustness tests. Finally, the fifth chapter documents the major conclusions, discusses the limitations of the thesis, and outlines suggestions for future research.9 0Item Restricted Detection and Quantification of Nicotine and Other Volatile Compounds in E-Cigarettes Using Gas Chromatography-Mass Spectrometry(Saudi Digital Library, 2025) Alzahrani, Amjad; Dayanne, MozanerElectronic cigarettes (e-cigarettes) are popular nicotine delivery systems, but their labeled nicotine content is often unregulated and potentially inaccurate posing a risk to consum ers. The purpose of this experiment was to develop and validate a Gas Chromatography-Mass Spectrometry (GC-MS) method to quantify the amount of nicotine in a disposable e-cigarette (IGET XXL) advertised as containing 5.0% nicotine. A direct weighing method was employed wherein 0.0716 g of e-liquid was dissolved in methanol within a 10 mL volumetric flask subse quently undergoing a 1-in-10 serial dilution. Quinoline was added as an internal standard and samples were analyzed by GC-MS in selected Ion monitoring (SIM) mode against a six point (0.5 25.0 mg/L) calibration curve. The method was validated demonstrating excellent linearity (R² = 0.9955) accuracy (98.5% recovery of a 10.0 mg/L QC standard) and precision (1.65% RSD). The primary finding was a measured nicotine concentration of 7.56 mg/g (0.757% w/w). This meas ured concentration is approximately 6 times lower than the 5.0% w/v (50 mg/mL) claimed on the product packaging representing only 16.7% of the advertised strength. These findings confirm a significant discrepancy between the labeled and actual nicotine content highlighting potential quality control issues in the e-cigarette market. This study demonstrates that the validated GC MS method is an effective and reliable tool for the independent chemical verification of such con sumer products.46 0Item Restricted The Effectiveness of Hybrid Micro-Grid System in Selected Locations in Saudi Arabia(Saudi Digital Library, 2026) ALLHIBI, HAMED; Alam, FirozThe need for socio-economic development, industrialisation, and lifestyle advancement propels rising energy demand globally. The majority of energy needs are met by fossil fuels (coal, oil, and gas), which emit significant greenhouse gas emissions, degrading the environment and accelerating the global climate impact. The greenhouse gas emission and its impact are more prominent in high energy-consuming nations like the Kingdom of Saudi Arabia, where most power is generated by fossil fuels. Although the country’s 35 million population is largely spread in major cities and towns (83%), a significant population (17%) still lives in rural and remote areas across the vast country (2.15 million square km). The power needs for most of these populations are met not by grid-connected power but by locally generated power (mainly diesel fuel). As a responsible nation, the Kingdom of Saudi Arabia has committed to the Paris Climate Agreement and adopted a plan to reduce fossil fuel use for power by gradually increasing renewable power generation, especially in remote and rural areas. The geographic location of Saudi Arabia offers the opportunity to enhance both solar and wind energy. However, the distribution of renewable energy (solar and wind) is not uniform throughout the country. Hence, the primary objective of this study is to explore the opportunity to harness renewable energy along with other types of energy, emphasising CO2 reduction and cost optimisation. The study is envisioned to develop a mathematical model of a hybrid power generation system incorporating solar, wind, and diesel energy for rural areas. This research aims to study and formulate accurate mathematical models to determine the hybrid microgrid system response for renewable energy location and allocation in rural and urban areas. A mathematical model is presented to design hybrid microgrid system based on the positioning of renewable energy resources besides the traditional resources to plan for the entire area. This new model takes into consideration demand needs and limited resources. The objective of the developed model is to minimise the emission and cost of the system while the demand is covered by using renewable energy. To quantify the power needs of the selected population, two areas along with the population— one in a rural area (Al-Gahah) and the other in an urban area (Jeddah)—have been selected. Data on household power usage have been obtained and analysed. Wind characteristics and solar irradiation data from the selected areas have also been collected. Based on collected data, the hybrid power generation mathematical model has been developed using five scenarios: a) diesel only, b) diesel and solar, c) diesel and wind, and d) diesel, solar, and wind. Initially, commercial software (HOMER) was used to predict optimal power generation for four scenarios. However, the optimised prediction did not fully address the need for local population requirements, especially the CO2 and cost together. To overcome these limitations, the mathematical power generation prediction model has been developed, validated by first an Excel-based model and later a Python-based model. The model validated by the case study data across four distinct scenarios, illustrate the robustness and efficacy of the model. It fulfils all constraints, determining the system configuration that achieves the desired function while complying with environmental and financial restrictions. The developed model is capable of predicting optimised power generation incorporating both cost and CO2 emissions. It can also be used to determine optimal power generation based only on cost or CO2 emissions. The model can be used to develop a hybrid power generation system using solar, wind, and other energy for areas in Saudi Arabia and elsewhere. The model can be used to enhance strategic, tactical, and operational planning for hybrid microgrid systems for achieving a more reliable power supply, a cleaner environment through diminished CO2 emissions, and reduced operational expenses for diverse microgrid and mini-grid power generation in Saudi Arabia and elsewhere.9 0Item Restricted Delineating the role of E-selectin in vincristine-induced peripheral neuropathy(Saudi Digital Library, 2025) ِِAlshammari, Ammar; Vetter, IrinaChemotherapy-induced peripheral neuropathy (CIPN) is a prevalent and debilitating adverse effect of cancer treatment, affecting a substantial proportion of patients undergoing chemotherapy. Vincristine, a widely used drug in the treatment of haematological and brain malignancies, is particularly associated with high rates of neuropathy, especially in children. The resulting sensory, motor and autonomic disturbances substantially impair patient quality of life and frequently necessitate dose reduction or discontinuation of chemotherapy, thereby compromising treatment outcomes. Despite its prevalence and impact, vincristine-induced peripheral neuropathy (VIPN) remains without effective preventive or therapeutic strategies, largely due to limited understanding of the underlying mechanisms. Traditionally, VIPN has been regarded as a neuron-centric disorder, arising from direct neurotoxicity caused by disruption of microtubule dynamics and axonal transport. More recent work, however, highlights the importance of neuroimmune and neurovascular mechanisms. In particular, immune cell infiltration into dorsal root ganglia (DRG) and peripheral nerves, coupled with activation of inflammatory pathways such as the NLRP3 inflammasome, have emerged as a key driver of this condition. Endothelial adhesion molecules are increasingly recognised as upstream regulators of these processes, orchestrating leukocyte recruitment across the blood–nerve barrier. Interestingly, preliminary data from our laboratory demonstrated that genetic deletion of endothelial E-selectin, an inducible adhesion molecule, abolishes VIPN in mice, strongly implicating E-selectin in macrophage-driven neuroinflammation. The present thesis was therefore designed to delineate the role of E-selectin in VIPN pathogenesis, with a particular focus on its contribution to immune cell recruitment, activation and the development of hypersensitivity. Accordingly, I employed a set of complementary studies spanning methodological development, functional testing and mechanistic investigation. First, a reproducible method for DRG immunohistochemistry was optimised, enabling accurate quantification of immune cell accumulation and supporting subsequent mechanistic investigations (Chapter 2). Then, blocking antibodies and knockout models revealed E-selectin as a key mediator of vincristine-induced hypersensitivity and macrophage accumulation at peripheral nerves (Chapter 3). Building on this, a novel intraplantar E-selectin injection model demonstrated that local administration of recombinant E-selectin was sufficient to induce macrophage-dependent allodynia, providing direct evidence that E-selectin initiates pro-nociceptive immune responses in vivo (Chapter 4). Finally, mechanistic studies showed that E-selectin engagement promotes macrophage adhesion, potentiates NLRP3 inflammasome activation and increases interleukin-1β (IL-1β) release (Chapter 5). Collectively, the findings presented here establish E-selectin as a previously unrecognised driver of vincristine-induced neuroinflammation. Rather than acting solely as an adhesion molecule, E-selectin is shown to orchestrate macrophage recruitment while simultaneously amplifying their pro-inflammatory activity, thereby linking vascular activation to nociceptor sensitisation. This work therefore reframes VIPN as not only a consequence of direct axonal toxicity, but also as a pathology rooted in endothelial–immune interactions and provides the first mechanistic evidence that E-selectin contributes directly to its development. More broadly, this work highlights E-selectin as a novel regulator of endothelial–immune communication in the peripheral nervous system. While the studies herein focus on VIPN, the implications extend to other neuropathic conditions in which macrophage recruitment and vascular activation are implicated. Importantly, the identification of E-selectin as a mechanistic driver of macrophage-mediated hypersensitivity provides a foundation for future studies to explore context-dependent roles of E-selectin and assess the therapeutic potential of targeting E-selectin in neuropathic pain.10 0Item Restricted The Impacts of the NAPLAN Test System on the Mental Health and Well-being of Educators and Teaching Strategies in Australia(Saudi Digital Library, 2025) Alghamdi, Sahar Abdullah; Lucas, Carey; Terry, CummingThe National Assessment Program - Literacy and Numeracy is Australia’s standard procedure to measure the performance of students in literacy and numeracy. Although this procedure was intended to identify weak areas and address them by allocating more resources and implementing appropriate strategies, it has been criticised in research due to its potential to dictate teaching strategies, curriculum development, and its overall impact on the mental health and well-being of students. This study aimed to investigate its implications on the mental health and well-being of teachers as well as the teaching strategies. Furthermore, it also aimed to study how teachers integrate student-centred, holistic and individually-tailored teaching strategies. A scoping review was implemented in this study to identify and extract the findings of the existing articles on this topic. Online research databases such as EBSCO Educational Research Database, ProQuest and Web of Science were searched using Keywords and Boolean Operators. A total of 11 articles were included in this scoping review. The extracted data indicate that NAPLAN impacts the well-being of teachers through excessive mental pressure and work responsibilities. It also influences teaching strategies, curriculum development and the learning quality of students. Although teachers try to implement student-centred and holistic teaching strategies. Based on this scoping review, a literature gap is identified regarding how teachers ensure holistic learning for students, which can be addressed through further primary studies.7 0Item Restricted Chief Executive Officer (CEO) Expertise and Firm Outcomes, Cost of Debt, and Analyst Forecast Properties: Evidence from Australia(Saudi Digital Library, 2026) Alsultan, Musaed; Imran, Haider; Effiezal, AswadiThis thesis contains three essays and examines the impact of chief executive officer (CEO) expertise (tenure, gender, age, and multiple directorships) on firm outcomes, the cost of debt, and analyst forecast characteristics in Australia. Chapter 1 describes the background and overall context of the study. It also discusses the theoretical and practical relevance of understanding how CEOs affect corporate financial decisions and stakeholder perceptions within the financial market. The chapter provides a basis for the three chapters which follow. Chapter 2 synthesises the literature concerning agency theory, upper echelons theory, and stewardship theory to create a conceptual framework linking CEO expertise with corporate outcome metrics, cost of debt, and analyst forecasts. Furthermore, this chapter discusses the prior empirical findings and any gaps that need to be filled by this thesis. Chapter 3 examines the relationship between CEO expertise and corporate outcomes. The study is based on a sample comprising 8,820 firm-year observations of Australian Securities Exchange (ASX) listed nonfinancial firms during the period 2004–2022. The CEO expertise is measured using CEO tenure and multiple directorships, while corporate outcomes are measured by return on assets (ROA), investment efficiency, Tobin’s Q, and cash flow. The results suggest that both CEO tenure and multiple directorships increase firm performance, thereby supporting the notion that seasoned CEOs contribute to the strategic value of the firm. Chapter 4 explores the impact of CEO expertise on cost of debt. Drawn from 8,441 firm-year observations of ASX-listed nonfinancial firms over the period 2004–2022, the findings suggest that both CEO tenure and multiple directorships are associated with higher costs of debt, possibly reflecting lenders’ fears of entrenchment or overcommitment. Chapter 5 explores how CEO tenure and multiple directorships impact analyst forecast properties. Drawing upon 4,266 firm-year observations, this study uncovers evidence that longer-tenured CEOs are associated with greater forecast accuracy and reduced dispersion/bias. I do not find any relationship between holding multiple directorships and analyst forecast properties. Overall, this study makes an important contribution to the corporate governance literature by providing clear evidence that CEO characteristics influence firms’ access to capital, market perceptions of CEOs, and financial reliability.Item Restricted Smart Technology Adoption for Promoting Sustainable Development in Rural and Remote Regions: The Case of Saudi Arabia(Saudi Digital Library, 2026) Alabdali, Salem; Salvatore, Flavio PileggiIn the era of the digital revolution, smart technology has become an integral part of daily life. Sustainable development, a global priority aimed at reducing inequality between communities, increasingly relies on smart technology as a strategic enabler. This is particularly important in isolated areas such as rural and remote regions. This study investigates smart technology adoption as a strategic approach to promoting sustainable development, with a focus on socio technical aspect enhancing social inclusion and economic growth. A mixed-methods approach was adopted. A research framework integrating multiple Information Systems theories was developed through critical analysis, incorporating sustainability from diverse perspectives relevant to these contexts. The study was conducted in Saudi Arabia across three key sectors representing the pillars of sustainability: education, healthcare, and business. Data were collected through 212 valid survey responses and 15 semi-structured interviews with organizational representatives. The findings identify key determinants of sustainable development in remote settings, including management support, human expertise, financial resources, relative advantage, perceived usefulness and ease of use, IT infrastructure, government policies, and socio-economic conditions. Socio-cultural perspectives showed a negative influence, reflecting local norms and traditions. These insights support policymakers in formulating effective strategies for inclusive and sustainable development.Item Restricted Distributed Leadership and Its Role in Empowering Women to Educational Leadership Positions in the Kingdom of Saudi Arabia (KSA)(Saudi Digital Library, 2025) Alazwari, Hanadi; Beutel, DeniseThe higher education sector in the Kingdom of Saudi Arabia is one of the most important enabling sectors for Saudi women seeking leadership roles. However, there is still a gap in the leadership participation of women compared with men. Traditional leadership approaches have failed to meet the needs of women in the emerging field of Saudi women leadership. This lack of progress has been largely due to the traditional roles of men and women in Saudi culture which is highly dominated by men and male perspectives. Women have traditionally been seen as homemakers with the care of family their most important job. Women have been restricted by social and traditional beliefs that they were not capable of leadership simply because they were women. While the caring of family is still a highly significant role for women, Saudi Arabian (SA) society is changing with the introduction of new legislation. In 2016, the Kingdom of Saudi Arabia (KSA) issued a policy, Vision 2030, in which women’s roles in society were outlined to include women taking up more leadership positions, particularly in the education sectors. This policy promotes women's rights and empowerment by advocating for higher wages and expanding employment opportunities for women across various sectors (Shura Council, 2021). Women are being offered new opportunities to make a significant contribution to the growth of the nation. In these early days of change it is important to understand how these new responsibilities for women are both perceived and enacted by those directly affected. This research explores university staff perceptions of women leadership in a Saudi university (both female and male) as it continues to evolve in this new cultural, economic, and social paradigm. As an alternative leadership approach to the traditional hierarchical male-dominated approach, distributed leadership may give women opportunities to develop their leadership iii skills and empower them for higher positions. It appears from the writing of the KSA’s Vision 2030 policy that distributed leadership may be the preferred leadership approach for women to adopt, although it is not strictly mandated. There is a view put forward in the literature that female characteristics are more amenable to a distributed leadership approach which advocates for collaboration, cooperation, and the inclusion of a greater number of employees than is found in a traditional approach that generally has only one leader. As yet, however, there has been little research that explores whether distributed leadership is the preferred approach taken by women in higher education leadership roles. The aim of this qualitative case study research was to investigate the perceptions and practices of women leadership in higher education in Saudi Arabia and to identify enabling and inhibiting factors that impact on women in realising leadership positions. This study provides important insights to address the gap in this area of research and understanding. While the focus of the research was on distributed leadership, it should be acknowledged that the participants in the research worked at a partially segregated university, that is, a university run by men with a women’s university on the same campus. Within this segregation, the women’s university must refer all final executive decisions to men. However, in the women’s university, women leaders have the power and responsibility to make decisions. This kind of leadership is described in the literature as a hybrid leadership approach. While the university overall had taken a hybrid approach to leadership, the current research focused on the women’s university only to determine whether distributed leadership was enacted there and, if so, how this approach was viewed. Findings indicated that women enacted distributed leadership in the women’s university through their practices of supporting colleagues, encouraging involvement of all leaders and aspiring leaders, and by disseminating the belief that women were not only capable of leadership but that they should grasp all opportunities to become leaders. This research makes a significant contribution by demonstrating how distributed leadership is iv already embedded within a hybrid leadership approach in higher education in Saudi Arabia. It provides valuable insights into the effectiveness of distributed leadership in mixed-gender environments while shedding light on its limitations in gender-segregated settings.6 0