Saudi Cultural Missions Theses & Dissertations
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Item Restricted Experimental Design, Monitoring, and Assessment of Bioretention Systems for Urban Stormwater Management(Cardiff University, 2025) Altuwairgi, Nailah; Ahmadian, Reza; Sapsford, DevinClimate change and urbanisation exacerbate urban flooding and stormwater pollution, causing significant environmental and socio-economic impacts. Bioretention systems provide decentralised solutions to these challenges; however, their effectiveness and longevity are dependent on optimised design and proactive maintenance, both of which are hindered by a lack of performance and monitoring data, particularly in a UK context. This research provides the first empirical evidence to support the design of UK-specific bioretention configurations through performance evaluation, and to inform maintenance strategies through the analysis of contaminant accumulation. The research comprised integrated laboratory and field studies. A series of column experiments was conducted in this study to evaluate the influence of two key design variables: vegetation and biochar amendments, on bioretention performance under simulated rainfall conditions representative of Cardiff, UK, with accelerated heavy metal loading. All designs consistently achieved high removal efficiencies (80-99%) for suspended solids and heavy metals. In contrast, phosphorus removal was more variable, ranging from 53% removal to significant net leaching, depending on the specific design configuration. Vegetation was critical for sustaining hydraulic function, effectively preventing clogging observed in non-vegetated systems, while providing secondary treatment benefits. Performance was species-dependent, with Carex pendula identified as the most effective for combined treatment and hydraulic performance. Biochar amendments, while beneficial for dissolved zinc removal, reduced suspended solids and particulate lead retention and were a net source of dissolved phosphorus, leaching up to 1.36 mg/L. The results emphasise that biochar amendments must be selectively optimised and validated for specific stormwater treatment objectives. Analysis of filter media profiles revealed that, the majority of heavy metals were captured in the top 0-3 cm layer, reaching potentially toxic concentrations. The investigation into heavy metal accumulation was further advanced through a field-scale study at two established bioretention sites in Cardiff. Traditional sampling and portable X-ray fluorescence (pXRF) were employed to map the spatial distribution of heavy metals and identify contamination hotspots. Concentrations in the surface layer (0-3 cm) ranged as follows: Cu: 15-69, Pb: 18-340, Zn: 69-583, and Cr: 13-95 mg/kg, with accumulation levels increasing with system age and decreasing with depth. While most metal concentrations fell well below screening levels, centralised inlets created hotspots approaching these limits for Pb and Cr. Therefore, prioritising diffuse inlets in design to promote a more uniform distribution, complemented by pXRF monitoring, enables targeted maintenance to keep all concentrations below screening levels indefinitely.3 0Item Restricted Perceptions Of Teacher Professional Development Among Elementary School Teachers in Riyadh, Saudi Arabia: A Qualitative Interview Study(Saudi Digital Library, 2025) Alsubaie, Hissah; Wiley, KathrynResearch indicates that Saudi Arabia's education system faces challenges to ensuring effective teacher professional development (TPD). Despite ongoing efforts, teachers often encounter barriers that hinder their professional growth and impact student outcomes. This study aims to identify and analyze these barriers thereby building from existing research. It explores the interplay of cultural norms, institutional constraints, and individual challenges within the Saudi educational context. The research used a phenomenological qualitative design to explore how Saudi teachers experience professional development within cultural, institutional, and individual contexts. Through in-depth interviews with 10 teachers who have engaged in professional development, the study investigates their experiences and perspectives on TPD implementation. Findings from this study revealed five major themes. Teachers highlighted challenges in program participation and content where training mostly lacked relevance and was hindered by heavy workloads. Cultural norms including gender segregation and family responsibilities also limited access to opportunities. Institutional barriers like insufficient resources, lack of substitutes and weak leadership support further constrained professional development. On an individual level, teachers faced limited freedom to choose suitable programs, few career advancement incentives and difficulties with timing and transportation. Despite these barriers, participants suggested improvements like needs-based and flexible training, stronger incentives linked to career growth, better infrastructure and the integration of technology to enhance access and impact. Ultimately, the study seeks to support the improvement of teacher professional development practices which can support enhanced teaching quality and improved student learning outcomes.9 0Item Restricted Prevention of Gestational Diabetes Mellitus (GDM); Targeting Early Pregnancy Intervention to Women at Risk(Saudi Digital Library, 2025) Quotah, Ola; Lucilla, Poston; White, SaraBackground: Gestational diabetes mellitus (GDM) is a common metabolic disorder of pregnancy, particularly among women living with obesity. GDM is associated with increased risk of short- and long-term adverse consequences for both the mother and her infant. Identification of women at high risk of developing GDM would facilitate targeted intervention in those who would benefit the most. This thesis comprises different studies, each aimed at enhancing the understanding, prediction and prevention of GDM in women who are at increased risk of the condition. Overarching aim: To identify pregnant women at higher risk of developing GDM and test the feasibility and efficacy of diet and/or metformin to improve glucose homeostasis and pregnancy outcomes. Methods: This thesis consists of a systematic review and meta-analysis in addition to three distinct studies. These are outlined below: i) Study (1): studies evaluating behavioural/pharmacological interventions or dietary supplements in the preconception period and in pregnant women with greater risk of developing GDM were assessed and evidence synthesised using a systematic review and meta-analysis. ii) Study (2): Using a prospective cohort (the GDM validation study), the performance of two pragmatic GDM prediction tools (model 1 and model 2) was compared in women with obesity. iii) Study (3): A secondary analysis was performed using data collected from women who took part in the UPBEAT study (UK Pregnancy Better Eating and Activity Trial). This analysis compared metabolic profiles in women identified as high-risk of developing GDM using the prediction tool, stratified by GDM diagnosis. Analyte 14 data, measured using a nuclear magnetic resonance platform and conventional assays, were compared between women who developed GDM and those who did not in early (15+0–18+6 weeks’ gestation) and mid-pregnancy (23+2–30+0 weeks’ gestation). iv) Study (4): A preliminary feasibility and Patient-Centred outcomes analysis of UPBEAT- Taking it Forward (TIF) was carried out. UPBEAT-TIF is an ongoing randomised controlled trial (RCT) of lifestyle advice with or without metformin compared to standard antenatal care in individuals identified as high-risk of developing GDM using the prediction tool. Results: i) Study (1): The systematic review and meta-analysis identified eighty-four RCTs (preconception=2, pregnancy=82). The review provided evidence that interventions targeted at women at risk of GDM may be an effective strategy for GDM prevention and highlighted the need for further studies using validated prediction tools or multiple risk factors to target high-risk women for intervention before and during pregnancy (Quotah et al., 2024). ii) Study (2): Model 2 incorporating non-biochemical factors (age/mid-arm circumference/systolic-blood pressure), haemoglobin A1c (HbA1c), glucose and triglycerides demonstrated a higher performance in predicting GDM compared to model 1 with non-biochemical factors, HbA1c and adiponectin (AUC 0.755 vs AUC 0.637; p=0.006). Model 2 could facilitate early detection among women with obesity and increased risk, enabling timely implementation of targeted lifestyle or pharmacological interventions for those who are most likely to benefit. However, external validation of the models' performance is underway. 15 iii) Study (3): The secondary analysis revealed biochemical differences between women with obesity identified as high-risk using the predictive tool who went on to develop GDM compared to those identified as high risk who did not. These differences were found both early in gestation and at the time of GDM diagnosis. The identified differences may be related to defective β-cell secretory function (Quotah et al., 2022). iv) Study (4): The preliminary feasibility analysis of UPBEAT-TIF RCT demonstrated that a targeted intervention in women at increased risk of GDM is a feasible approach. Preliminary analysis of outcomes did not support the use of lifestyle interventions with or without metformin to improve glucose concentrations among women who are at increased risk of GDM. The unexpectedly low rates of GDM across all groups, including the controls, warrant additional explorations. At the time of writing, recruitment to the study had not yet reached the predefined sample size. Conclusion: Overall, this thesis makes innovative contributions to understanding GDM pathophysiology and identifying high-risk women in order to assess the potential benefit of interventions. Intervention studies in the preconception period and in early pregnancy that target women at increased risk of GDM using multiple risk factors or validated prediction tools are warranted, as a strategy towards prevention of GDM and improved maternal and infant health among those who would benefit the most.3 0Item Restricted Designing and Implementing Efficient and Secure Hardware Primitives for ML-KEM(The University of Sheffield, 2026) Alhassani, Abdullah; Benaissa, MohammedThe transition to post-quantum cryptography (PQC) has become a critical urgency in securing digital communications against the emerging threat of quantum computing. The Module-Lattice Key Encapsulation Mechanism (ML-KEM), formerly known as CRYSTALS-KYBER and recently standardised by National Institute of Standards and Technology (NIST) as the primary PQC algorithm for key encapsulation mechanism, offers strong theoretical security guarantees but poses significant implementation challenges in terms of efficient and secure implementation. This thesis presents the design, optimisation, and verification of efficient and secure hardware polynomial multipliers for ML-KEM, with a focus on performance, area efficiency, and resistance to side-channel and fault injection attacks. Towards this goal, the residue number system (RNS) and the redundant residue number system (RRNS) were considered as efficient and inherently secure methods of implementation. Firstly, a high-speed number theoretic transform (NTT)-based polynomial multiplier for ML-KEM is presented. The proposed architecture uses RNS to accelerate the main operation in the NTT, i.e., integer modular multiplication. The design uses read only memory (ROM)-based architecture to implement the RNS design and is integrated with an efficient memory access to form a hardware accelerator on a Field Programmable Gate Array (FPGA), yielding a significant improvement over state-of-the-art results. Secondly, an RNS NTT-based polynomial multiplier for ML-KEM is presented. The RNS methodology is extended to the whole polynomial multiplication of ML-KEM for efficiency and side-channel protection. The results of the FPGA implementation and experimental side-channel leakage evaluation show an efficient implementation and effectiveness in protecting against side-channel leakage. Thirdly, a fault detection architecture for the polynomial multiplication of ML-KEM is proposed. The design utilises the RRNS and is applied to the polynomial multiplication of ML-KEM. The proposed method can detect single faults in RRNS residues with 100% error coverage and the FPGA implementation results show minimal area and time overhead.3 0Item Restricted Real-Time Control and Reconfiguration in Eigen-basis Coordinates for Multi-phase Unbalanced Distribution Networks(Imperial College London, 2026) Aljadani, Abduljalil; Bikash, PalThe increasing penetration of distributed energy resources (DERs) has extended the scope of distribution network management from the medium-voltage (MV) level into the low-voltage (LV) level. This transition introduces new challenges for Distribution Management Systems (DMS) to satisfy real-time operational requirements. The combination of unsymmetrical line configurations and unbalanced load conditions in LV networks necessitates detailed multiphase modeling. These characteristics prevent the direct adaptation of computationally efficient algorithms traditionally used in transmission system management, which rely on balanced positive-sequence representations of the network. This thesis introduces the modeling of LV networks in eigen-basis coordinates to enable efficient implementation of DMS functions. The assessment and optimization functions formulated in eigen-basis coordinates include power flow calculation, Volt/Var Control (VVC), and Optimal Network Reconfiguration (ONR). The proposed model employs eigenvector decomposition to diagonalize the admittance matrix of four-wire LV lines, improving computational efficiency and accurately computing the neutral-to-ground voltage. Case studies demonstrate a reduction of over 50\% in the number of non-zero elements in the LU factors of the bus admittance matrix and speed-up factors of 2.79 on the IEEE-123 bus feeder and 3.62 on the IEEE-8500 node feeder in VVC execution times, compared to the phase-coordinate model. A framework is proposed for applying low-rank update methods to model network topology changes using the eigen-basis coordinate representation of distribution networks. The proposed framework is integrated into a heuristic ONR algorithm and tested on the non-synthetic European low-voltage (NSELV) network and the IEEE 123-bus feeder. Results demonstrate significant reductions in computational requirements compared with practical methods currently used in industry: the compensation method requires only one-third of the power flow runs needed by the multiphase power injection method to simulate a switch exchange, and the partial refactorization method achieves speed-up factors of up to 100× compared to full refactorization.7 0Item Restricted Benzo (Aza) Di- and Tripyrrins, and Their Metal Complexes(Saudi Digital Library, 2025) Alturk, Ala; Cammidge, AndyThis thesis continues the investigation of our group's synthesis of benzo-fused aza di- and tripyrrins. The main focus of this work is the complexation of these ligands with various metals. Therefore, symmetrical and unsymmetrical benzo azadipyrrins were successfully synthesised. The synthesis of benzo azatripyrrin was optimised in this work. The success of this objective led to the preparation of these compounds and various derivatives. The path to producing homoleptic complexes faced several obstacles. To solve this problem, many experiments were attempted with various purification techniques. Complexation of azatripyrrn was not achieved. A range of reaction conditions failed to reach our goal. These conditions were gradually modified until a breakup and decomposition were observed. On the other hand, the complexation of symmetrical and unsymmetrical benzo azadipyrrins proposed other difficulties. The main problems in this path were the produced complexes' purification and stability. Several attempts were made using different metals. Unlike azatripyrrin, successful complexation of azadipyrrin was achieved using palladium metal. The unsymmetrical azadipyrrin palladium complex was the first to be successfully synthesised and characterised in 1:1. Through ligand modification, a range of complexes containing ferrocene and thiophene groups were synthesised. While these derivatives are highly interesting in the organometallic field, the goal was to study the insertion behaviour of palladium metal. Modifying this successful technique led to the preparation of symmetrical azadipyrrin palladium complexes and their derivatives. Due to time constraints, these palladium complexation procedures were briefly tested with other metals in the preparation of azadipyrrin complexes. Additionally, test reactions were made to synthesise azatripyrrin palladium complexes. While the results are not conclusive, these tests are the seeds of further work.5 0Item Restricted THE INFLUENCE OF CYBERSECURITY KNOWLEDGE AND ATTITUDES ON ONLINE RISKY BEHAVIORS AMONG BANK EMPLOYEES IN SAUDI ARABIA(Saudi Digital Library, 2025) Alzahrani, Salwa; Mbaziira, AlexThe rapid digitization of banking services in Saudi Arabia has intensified cybersecurity challenges, particularly those influenced by human factors. This study examined how cybersecurity knowledge and attitudes shape risky online behaviors among bank employees, addressing the persistent vulnerability posed by human behavior despite technological safeguards. Grounded in the Health Belief Model and Social Cognitive Theory, the research explored how cognitive elements, such as knowledge, perceived susceptibility, perceived severity, and self-efficacy, together with attitudinal factors, including perceived benefits of compliance, affect employees’ cybersecurity practices. Using a quantitative design, survey data from 133 banking employees were analyzed through descriptive statistics, principal component analysis (PCA), and multiple regression. The PCA identified three main dimensions influencing behavior: perceived susceptibility and benefits of compliance, cybersecurity knowledge and perceived severity, and cybersecurity attitudes and self-efficacy. Regression analyses showed that these factors significantly predicted several risky behaviors, particularly those involving rationalization and convenience-based decisions. Attitudes and self-efficacy were the strongest deterrents to behavior motivated by perceived inconvenience, while knowledge and perceived severity reduced the tendency to justify insecure practices. Demographic variables had minimal influence, indicating that psychological and cognitive factors are stronger determinants of cybersecurity behavior within the Saudi banking sector. Keywords— Cybersecurity knowledge, Cybersecurity attitude, Risky online behavior.7 0Item Restricted The Effect of positional noise and colours on reading performance in human vision(Saudi Digital Library, 2026) Alsalhi, Abdullah; Day, Mhaira; Strang, NaillEnhancing visual function is an important aspect of vision care. Reading difficulties among adults and children may adversely affect their quality of life through work and school education (Stifter et al., 2005). Changes in lighting and colour are known to influence visual comfort and reduce perceptual difficulties that affect reading for those with poor vision (Northway et al., 2010). In the initial experimental chapters of this thesis a visual noise model is used to simulate different levels of reading performance in young participants to investigate how reading performance, including reading rate and correct reading rate, is affected by changing the lighting conditions of the reading task. The first experiment chapter (Chapter 3) investigates the effect of introducing visual noise to a reading task in young participants with good near vision. Reading performance reduced when visual noise was introduced for both reading types (lexical and sub-lexical). The reading rate for sub-lexical words was slower than the reading rate for lexical words as the introduced noise disrupted word recognition or created cortical noise. The second experiment chapter (Chapter 4) investigates the effect of changing wavelengths or colours on reading performance when visual noise is introduced in participants with good vision. We found that the reading rate is not affected by changing wavelength or colour for both reading types. In the lexical words condition, however, introducing cortical noise affected word recognition differently with different wavelengths. The role of short wavelength and white colour in enhancing orthographic reading and word recognition is clear as it reduces the effects of positional noise (reducing the effects of cortical noise). The correct reading rate change differently with different wavelengths, even when positional noise is introduced. In sub-lexical words, the reading rate was almost same under different wavelengths and colour. However, the reading rate under long wavelength (red) was slower compared with other wavelengths and colour in both reading types. The third experiment chapter (Chapter 5) investigates the effect of changing the wavelength and colour on reading performance for amblyopic participants monocularly (amblyopic and non-amblyopic eyes) with and without cortical noise for both reading types. We found that the reading rate in amblyopic eye under different wavelengths and colour with and without cortical noise in different reading types was slower than the reading rate in non-amblyopic eyes. In non-amblyopic eyes, the reading rate reduction with lexical words was varied as varied the wavelengths and colour when cortical noise created. However, with sub-lexical words the reduction in reading rate was almost same under different wavelengths and colour. In amblyopic eyes, the reading rate reduction with with both reading types was almost similar but the reading rate in sub-lexical words was slower than lexical words. Also, the reading rate under long wavelength was the lowest compared other colours in all conditions. The fourth experiment (Chapter 6) investigates the effect of changing colours on central crowding reading for normal participants and how the object can be affected by changing the flanker distance and unflanked target. We found that central reading crowding is considered as a type of visual crowding. Also, different colours have different effects on central crowding. However, central crowding reading with red was not affected by changing the flankers.6 0Item Restricted خصوصية قواعد اثبات الجرائم الالكترونية في القانون الاردني -دراسة مقارنة(Saudi Digital Library, 2026) العمراني, اسراء; الخصيلات, عبداللهعنوان الدراسة: خصوصية قواعد إثبات الجرائم الإلكترونية في القانون الأردني (دراسة مقارنة). تتناول هذه الدراسة الإطار القانوني والإجرائي المنظم لعملية الإثبات في الجرائم الإلكترونية، مسلطة الضوء على التحديات التي تواجه العدالة الجنائية في التعامل مع الدليل الرقمي نظراً لطبيعته غير المادية وسهولة تعديله أو محوه. اعتمدت الدراسة المنهج التحليلي المقارن بين التشريع الأردني والنظام السعودي، وخلصت إلى مجموعة من النتائج المحورية، أبرزها: إثبات وجود تباين إجرائي في صلاحيات الضبط والتفتيش الإلكتروني، حيث يضع المشرع الأردني قيوداً مرتبطة بوقوع الجريمة ابتداءً، بينما يتوسع النظام السعودي في صلاحيات الاستدلال مع تشديد الرقابة القضائية. كما أكدت الدراسة على أن مشروعية الدليل الإلكتروني ترتبط ارتباطاً وثيقاً بسلامة "سلسلة الحيازة" وضمان عدم العبث بالبيانات من لحظة الضبط وحتى تقديمها للمحكمة. وتقدم الدراسة جملة من التوصيات لرفع كفاءة المنظومة القانونية، أهمها: ضرورة إيجاد تعريف تشريعي موحد وشامل للجريمة الإلكترونية في القانون الأردني، وتقنين إجراءات "التحفظ العاجل" على البيانات الرقمية بنصوص واضحة، بالإضافة إلى تعزيز الدور الفني للقضاء من خلال اعتماد معايير تقنية دقيقة لفحص حجية الأدلة الرقمية بما يضمن تحقيق التوازن بين مكافحة الجريمة المستحدثة وصون الحقوق والحريات العامة.0 0Item Restricted أثر إدارة الأزمات والمخاطر على كفاءة وإستمرارية العمل فى المؤسسات العامة (دراسة حالة)(Saudi Digital Library, 2025) Alsamdani, Ghareeb; Mohamed,Abdelhamid, Sabry; Ahmed, ElSayed,Abdelrazekتتناول هذه الدراسة أثر إدارة الأزمات والمخاطر على كفاءة واستمرارية العمل في المؤسسات العامة، من خلال تطبيقها على هيئة الهلال الأحمر السعودي كنموذج عملي. وتهدف إلى تحليل دور هذه الإدارة في تحسين الأداء المؤسسي وتعزيز القدرة على الاستجابة للأزمات والطوارئ. اعتمدت الدراسة على المنهج الوصفي التحليلي، بالإضافة إلى دراسة ميدانية باستخدام الاستبيانات والمقابلات مع العاملين والمستفيدين. وقد تم التركيز على تقييم مستوى الكفاءة التشغيلية، وقياس رضا المستفيدين، وتحليل فعالية استراتيجيات إدارة المخاطر. أظهرت النتائج أن إدارة الأزمات والمخاطر تلعب دورًا محوريًا في تحسين كفاءة الأداء وتقليل فترات التعطل، مما يضمن استمرارية تقديم الخدمات، خاصة في المؤسسات الصحية والخدمية. كما كشفت الدراسة عن بعض التحديات، مثل ضعف الموارد، وقصور نظم الإدارة، وعدم كفاية التدريب في بعض الجوانب. وأوصت الدراسة بضرورة تطوير استراتيجيات إدارة الأزمات، وتعزيز التدريب والتأهيل، واستخدام التكنولوجيا الحديثة، بما يسهم في رفع كفاءة الأداء وتحقيق استدامة الخدمات في المؤسسات العامة.1 0