SACM - Malaysia
Permanent URI for this collectionhttps://drepo.sdl.edu.sa/handle/20.500.14154/9660
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Item Restricted GRAPH-BASED ALGORITHMS FOR MULTI-VERSION CONCURRENCY CONFLICT DETECTION AND RESOLUTION IN HYPERLEDGER FABRIC BANKING TRANSACTIONS(Saudi Digital Library, 2026) Alzahrani, Fawaz Mohammad; Idris, Mohd Yazid; Rohani, Mohd Foad; Budiarto, RahmatHyperledger Fabric is a permissioned blockchain framework used widely across enterprise systems. It suffers from performance degradation under high-contention workloads due to conflict transactions identified as Multi-Version Concurrency Control (MVCC) Read Conflict. This thesis proposes an integrated three-stage solution that detects, corrects, and parallelizes conflict transactions to raise throughput and reduce latency. The first contribution is Hyperledger Fabric Graph Isomorphism Network (HFGIN), which encodes each transaction batch as a graph and learns dependency patterns from overlapping read and write sets generated by SmallBank banking operations. HFGIN identifies likely MVCC conflicts before the ordering and commit phases, it avoids wasted endorsement and execution process effort. The second contribution, Hyperledger Fabric Graph Isomorphism Network-Dependency-aware Correction (HFGIN-DC), computes a dependency degree from the transaction dependency graph and reorders conflict-prone transactions. This dependency-aware correction prevents cascading aborts and improves throughput. The third contribution is Hyperledger Fabric Graph Isomorphism Network-Conflict Correction and Parallelization (HFGIN-CCP), which classifies transactions as low or high dependency. It executes independent transactions concurrently and serializes dependent transactions. The experimental evaluations based on the SmallBank benchmark dataset demonstrated that HFGIN improved detection accuracy from 78.95% for Graph Isomorphism Network (GIN) to 82.20%. HFGIN-DC outperformed the FabricSharp system, increasing throughput from 415 transactions per second (TPS) to 460 TPS, while HFGIN-CCP reduced latency from 2.6 seconds to 1.4 seconds at a block size of 500 transactions. The three algorithms form a coherent solution for managing MVCC conflict transactions in banking workloads on the Hyperledger Fabric blockchain system.16 0Item Restricted COEFFICIENT ESTIMATES AND SUBORDINATION THEOREMS FOR CLASSES OF ANALYTIC FUNCTIONS(Saudi Digital Library, 2026) ALKHATTAF, NUHA SULAIMAN M; MAISARAH, BINTI HAJI MOHDGeometric Function Theory is a branch of mathematics distinguished by its intriguing connection between geometry and analysis. This thesis presents several important results on coefficient estimates for classes of analytic functions. The upper bounds for the second Hankel determinant and symmetric Toeplitz determinants are investigated for functions belonging to two subclasses defined in the open unit disk, namely subclasses of analytic and univalent functions, such as starlike and convex functions. In addition, two classes of order α are introduced, specifically the classes of analytic starlike and convex functions of order α, where 0 ≤ α < 1. Coefficient estimates for these classes are obtained via symmetric Toeplitz determinants, from which several special cases are identified. Furthermore, estimates of the initial Maclaurin coefficients are derived, and Fekete-Szego ̋ type inequalities are established for three new classes of analytic and bi-univalent functions defined by Gegenbauer polynomials. Certain special cases and their corresponding consequences are also discussed. This thesis also addresses differential subordination, differential superordination, and quasi-subordination results for analytic functions. Three subclasses of analytic and bi-univalent functions are defined in the open unit disk, and upper bounds for the second Hankel determinant are obtained for functions in these subclasses. Finally, a suitable class of admissible functions is considered using the Dziok–Srivastava linear operator, where subordination and superordination results are investigated. The findings in this thesis on coefficient estimates of analytic functions are expected to contribute to and stimulate further research in this area.20 0Item Restricted Evaluating the Impact of a Structured Educational Intervention on the Quality of Laboratory Investigations for the Diagnosis and Prevention of Hepatitis C Virus Infection in Arar City, Saudi Arabia(Saudi Digital Library, 2026) ALANAZI, ABDULLAH; Abdullah, ErlinaBackground: Hepatitis C Virus (HCV) infection remains a significant global public health concern despite major advances in diagnosis and treatment. Although Saudi Arabia is classified as a low-prevalence country, achieving national and global HCV elimination goals requires sustained attention to accurate diagnosis, effective screening, and high-quality laboratory services. Aim: This study aimed to evaluate the impact of a structured educational intervention on the quality of laboratory investigations for the diagnosis and prevention of Hepatitis C Virus (HCV) infection in Arar City, Saudi Arabia. Methods: A descriptive cross-sectional study with a quasi-experimental educational intervention component was conducted across five major healthcare institutions in Arar City. Laboratory records were reviewed to assess HCV prevalence, screening outcomes, diagnostic performance, and quality control indicators. A structured and validated questionnaire was administered to laboratory personnel to evaluate knowledge, technical competency, continuing professional development, and quality assurance practices. Internal Quality Control (IQC) and External Quality Assessment (EQA) records were also evaluated. A structured educational and training intervention was subsequently implemented, and pre- and post-intervention outcomes were compared to assess changes in diagnostic performance and laboratory practice. Results: The prevalence of HCV infection in Arar City was 0.3%, confirming that the region remains a low-endemic area. Existing screening programs contributed to case detection and disease surveillance, although opportunities for improvement in targeted screening and linkage to care were identified. Laboratory technicians generally demonstrated adequate technical competency; however, gaps in specialized training and continuing professional development were observed. Quality assurance systems were strong, with an overall IQC success rate of 95.1% and 100% EQA compliance across participating laboratories. Diagnostic performance was excellent, with sensitivity reaching 100% and specificity 98.2%. Following implementation of the educational intervention, non-confirmed RIBA outcomes decreased from 22 cases before the intervention to 9 cases after the intervention, representing a 59.1% reduction and indicating improved diagnostic consistency. Conclusion: The findings demonstrate that high-quality laboratory investigations are essential for accurate HCV diagnosis and effective prevention. The combination of low HCV prevalence, strong laboratory quality systems, excellent diagnostic performance, and measurable improvement following educational intervention highlights the importance of continuous professional development, quality assurance, and evidence-based screening strategies. Strengthening laboratory services and workforce competency will further support Saudi Arabia’s Vision 2030 healthcare objectives and ongoing efforts to eliminate HCV as a public health threat.27 0Item Restricted EVALUATING THE IMPACT OF QUALITY IMPROVEMENT INTERVENTION ON DIAGNOSTIC ACCURACY OF HIV SCREENING IN BLOOD DONORS: A STUDY IN NORTHERN SAUDI ARABIA(Saudi Digital Library, 2026) Alanazi, Bader Mudhhi Essa; Rathimalar, AyakannuThis study evaluates the impact of quality improvement interventions on the accuracy of HIV screening among blood donors in the Northern Borders Region of Saudi Arabia, with a focus on the Central Blood Bank. Ensuring safe blood transfusion is critical, as inadequate screening may lead to the transmission of infectious diseases, particularly in low-prevalence settings where minor inaccuracies can compromise blood safety. A mixed-methods approach was employed. Quantitatively, a retrospective analysis of 385 blood donor samples was conducted to assess diagnostic performance, including sensitivity, specificity, and error rates. Results showed one true positive, six false positives, and no false negatives, yielding a false-positive rate of 1.56% and a false-negative rate of 0%. Although overall sensitivity was high, the low positive predictive value highlighted the importance of confirmatory testing and robust quality control measures. In addition, the effectiveness of a quality improvement intervention was evaluated through a structured training program delivered to 30 laboratory staff. The intervention significantly improved performance, with mean test scores increasing from 11.07 to 14.00 (p < 0.001), alongside improved internal consistency (Cronbach’s alpha: 0.762 to 0.794). Qualitative findings identified three key sources of variability affecting HIV testing performance: pre-analytical, analytical, and post-analytical factors, including inconsistencies in sample handling, equipment maintenance, and result interpretation. Overall, the findings demonstrate that both procedural weaknesses and staff competency gaps can affect HIV screening accuracy. Strengthening standardization, continuous training, and quality assurance systems is essential to enhance blood safety and ensure reliable transfusion services in the region.15 0Item Restricted CODE-SWITCHING IN SAUDI EFL CONTEXTS: ATTITUDES, PERCEPTIONS, AND MOTIVATIONAL IMPLICATIONS(Suadi Digital Library, 2026) Alsulami, Maryam; Husain, Sharifah ShahnazArabic-English code-switching is common in Saudi EFL classrooms, where instructors and students alternate between the two languages to support learning. This study investigates Saudi EFL learners' attitudes toward code-switching, their perceptions of instructor practices, and how these influence motivation to learn English. The three objectives are: (1) to investigate students' attitudes toward Arabic-English code- switching, (2) to analyse their perceptions of instructor code-switching practices, and (3) to evaluate how these attitudes influence their motivation. A mixed-methods design was used: a questionnaire with 150 students and semi-structured interviews with five participants. Myers-Scotton's Markedness Model and Dörnyei's L2 Motivational Self System guided the analysis. Quantitative results showed that 88.8% of students agreed that Arabic aids comprehension, and 78.1% preferred teachers who code-switch. Significant positive associations were found between positive attitudes toward code- switching and motivation (χ2 = 8.46, p = .004), and between perceptions of instructor code-switching and motivation (χ2 = 5.60, p = .018). Qualitative findings confirmed that code-switching enhances comprehension, reduces anxiety, and encourages participation, but students cautioned against excessive use. The study makes two theoretical contributions: it refines the Markedness Model by adding pedagogical purpose as a moderating variable, and it refines the L2 Motivational Self System by distinguishing between external and internal forms of the Ought-to L2 Self. A context-specific pedagogical model, Scaffolded Bilingual Circulation, is also proposed. The study concludes that balanced, strategic code-switching supports learning and motivation. Instructors should align code-switching with instructional goals to maintain comprehension while ensuring sufficient English exposure.22 0Item Restricted SMOKING INITIATION AND CESSATION: THE INFLUENCE OF SOCIO-DEMOGRAPHIC FACTORS, KNOWLEDGE OF RESPIRATORY DISEASES, AND PULMONARY FUNCTION RISKS IN POPULATIONS WITH A HEAVY SMOKING HISTORY IN KLANG VALLEY(Saudi Digital Library, 2026) ALShakhs, Fatemah; Idris, Adewale AhmedThis study explores the roles of socio-demographic factors, knowledge of respiratory diseases (KRD), and pulmonary function risks (PFR) in influencing smoking initiation and cessation among individuals with a heavy smoking history in Klang Valley, Malaysia. Guided by the Health Belief Model (HBM), Social Cognitive Theory (SCT), and the Theory of Planned Behavior (TPB), this research employed a quantitative cross-sectional design using a structured questionnaire distributed to 400 participants. Path analysis and predictive modelling were conducted using the Partial Least Squares Structural Equation Modelling (PLS-SEM) approach to examine direct effects, moderated relationships, and the predictive capacity of the proposed behavioural framework. Results from the structural model indicate that KRD had a significant positive effect on smoking initiation (β = 0.686, p < 0.001) and a significant negative effect on smoking cessation (β = –0.269, p < 0.001), suggesting that higher health knowledge alone does not deter smoking uptake nor strongly support cessation without additional behavioural reinforcement. In contrast, PFR demonstrated a significant negative relationship with smoking initiation (β = –0.204, p = 0.002) and a strong positive relationship with smoking cessation (β = 0.726, p < 0.001), indicating that perceived vulnerability to respiratory impairment functions as a powerful cue for behavioural change. The moderated structural model revealed that age, education level, and income significantly influenced the relationships between KRD, PFR, and both smoking behaviours, whereas gender did not moderate any pathway. The predictive model showed strong explanatory performance, with R² = 0.411 for smoking initiation and R² = 0.459 for smoking cessation, supported further by substantial predictive relevance (Q² = 0.400 and 0.440). These results confirm the robustness of integrating cognitive, perceptual, and socio-demographic determinants into a unified predictive framework. This study contributes a validated prediction model for understanding smoking behaviours in an urban Malaysian context, offering practical implications for targeted, demographically sensitive public health interventions. The findings underscore the importance of incorporating socio-cultural context, respiratory health knowledge, and perceived lung vulnerability into tobacco control policies and cessation strategies in Malaysia.2 0Item Restricted DEVELOPMENT OF NOVEL PMMA NANOCOMPOSITES AS LIGHTWEIGHT SHIELDING MATERIALS FOR GAMMA AND X RADIATION(Saudi Digital Library, 2026) ALMUTERY, AML AIED S; ALMUTERY, AML AIED SDespite the effective use of ionizing radiation in the medical field, radiation exposure remains a health hazard and poses threats to human life. In turn, this requires the development of radiation shielding materials. A radiation shield is primarily composed of lead due to its physical and mechanical properties, but lead might be toxic in the case of dust on the surface of lead objects. Polymer-based radiation shields can be utilised in the radiation shielding field due to their excellent physical and chemical properties, ease of fabrication, low manufacturing costs, and toughness. Also, their radiation shielding properties can be improved by using high atomic number fillers. The development of lead-free poly(methyl/methacrylate) PMMA-based nanocomposites reinforced with the following nanoparticles is the focus of this study: bismuth oxide magnesium oxide composites (Bi2O₃:MgO), bismuth oxide-silicon oxide composites (Bi2O₃:SiO₂) and magnesium oxide-silicon oxide composites (MgO:SiO₂) for gamma and X-ray shielding. Despite the addition of nanoparticles, PMMA's chemical stability is confirmed by the fourier-transform infrared spectroscopy's (FTIR) lack of new absorption bands in1000–4000cm-1 spectrum. The X-ray diffraction (XRD) with discrete peaks of crystallinity that correspond to Bi2O₃, MgO, and SiO₂ fillers showed that the PMMA matrix was amorphous, indicating a successful composite production. The scanning electron microscopy (SEM) study showed an equal dispersion of the nanoparticles up to 20 weight percent, whereas a tiny lump was seen at higher loadings. The optical properties were investigated with the help of a UV–Visible Spectrophotometer. The results for the optical properties showed that when the nanocomposites content was increased in the PMMA matrix the Urbach energy (∆E), refractive index (n) increased, while the energy optical band gap (Eopt) registered a decrease in both electron transition direct and indirect. Pure PMMA had a density of 2.72 g/cm3, while sample PMMA/25 wt% Bi2O3:MgO had a density of 3.63 g/cm3. Due to increased photon-matter interaction, the optical band gap of the highly loaded composites increased from 4.64 eV in the pure PMMA to 5.56 eV. At 662 keV, the linear attenuation coefficient (LAC), one of the radiation shielding tests, rose from 0.20 cm-1 for the pure PMMA sample to 0.28 cm-1 for PMMA/25 wt% Bi₂O₃:MgO, whereas the corresponding HVL dropped from 3.36 cm to 2.45 cm. Among other samples, PMMA/25 weight percent Bi2O3:MgO had the best shielding capability, with a radiation protection effectiveness value near that of lead at a diagnostic range. Focus on surface functionalization of the nanoparticles should be examined in future studies as well as multilayer composite designs, and full biocompatibility and mechanical assessments for wearable radiation shielding applications.10 0Item Restricted ROLE OF IT ATTITUDE AND IT CULTURE IN E-LEARNING USAGE BEHAVIOUR MODEL WITHIN GULF COOPERATION COUNCIL PUBLIC UNIVERSITIES(Saudi Digital Library, 2026) ALMANYI, NOORAH ABDULLAH; FADHIL, AHMAD BIN YUSOFThe sustained use of e-learning in higher education has become a strategic priority in the Gulf Cooperation Council (GCC) as universities transition from emergency remote teaching to long-term digital learning. Despite substantial investments in digital infrastructure, many academic staff remain hesitant to continue using e-learning platforms after the COVID-19 pandemic. This study develops and validates a post-adoption model of e-learning use among academic staff in GCC public universities by integrating the Information Systems Success Model (ISSM) and the Technology Acceptance Model 1 (TAM1). The model examines how system-related factors, system quality, information quality, and service quality, shape behavioural intention and use behaviour through the mediating role of Information Technology (IT) attitude and the moderating role of Information Technology (IT) culture. Data were collected using an online survey approach from 394 academic staff across public universities in the GCC using a purposive sampling approach. The measurement and structural models were analysed using SmartPLS 4. The results show that system-related factors have significant positive effects on both behavioural intention and use behaviour of e-learning. IT attitude was found to significantly influence behavioural intention and use behaviour and to partially mediate the effects of system-related factors. Behavioural intention was also a strong predictor of actual use behaviour, confirming its central role in post-adoption contexts. IT culture did not moderate the relationship between system-related factors and behavioural intention but significantly strengthened the relationship between IT attitude and behavioural intention, indicating that a supportive digital culture enhances the translation of positive attitudes into sustained commitment to e-learning. The study contributes to theory by advancing a behaviour-centred, post-adoption framework that integrates technical system quality with psychological and cultural mechanisms. Practically, the validated model provides GCC universities with a diagnostic and strategic tool for strengthening long-term engagement with e-learning through improvements in system performance, staff attitudes, and institutional digital culture.11 0Item Restricted NEONATAL ECHOCARDIOGRAPHY: CORRELATION BETWEEN CLINICAL FINDINGS AND ECHOCARDIOGRAPHIC RESULTS(Saudi Digital Library, 2026) ALMARSHUD, SAAD SALEH S; Mohd, Hanafi AliBackground: Congenital heart disease (CHD) remains one of the most prevalent causes of neonatal morbidity and mortality worldwide. Early recognition through clinical assessment and echocardiography is vital for improving outcomes. However, the accuracy of bedside clinical examination in detecting cardiac abnormalities is often limited. This study evaluates the diagnostic correlation between clinical findings and echocardiographic results in neonates to determine the effectiveness of physical examination as a screening tool for CHD. Objectives: To assess the relationship between clinical examination and echocardiographic findings in neonates, determine the prevalence and spectrum of echocardiographic abnormalities, and evaluate the diagnostic accuracy of clinical signs in detecting structural or functional cardiac lesions. Additionally, to compare echocardiographic findings between preterm and full-term neonates and propose recommendations for improved neonatal cardiac screening. Methods: A cross-sectional study was conducted on 190 neonates (preterm and full-term) evaluated at Prince Sultan Cardiac Center, Qassim, Saudi Arabia over one year, from January 1, 2024, to December 31, 2024. Each neonate underwent a detailed clinical examination followed by transthoracic echocardiography performed. Data included demographic characteristics, perinatal risk factors, and both clinical and echocardiographic parameters. Echocardiographic findings were categorized as transitional (PFO, PDA), functional (pulmonary hypertension), or structural (ASD, VSD, PS, CoA, AVSD, HCM, DCM). Statistical analyses were conducted to assess correlations and diagnostic accuracy. Results: Of the 190 neonates studied, 173 (91.1%) showed abnormal echocardiographic findings, most of which were transitional or mild structural defects. After excluding physiologic findings, 13.7% were classified as structural CHDs—predominantly ASD, VSD, mild PS, and CoA—with few major cyanotic lesions. Clinical signs such as cardiac murmurs, cyanosis, and respiratory distress were strongly associated with abnormal echocardiographic results. Preterm neonates and those with perinatal risk factors (e.g., maternal diabetes, NICU admission) demonstrated higher rates of cardiac abnormalities. Conclusion: Clinical examination alone is insufficient for reliable detection of neonatal CHD, as many structural or transitional cardiac findings may be clinically silent. Echocardiography remains the gold standard for accurate diagnosis and classification of cardiac lesions in neonates. The study emphasizes the need for routine echocardiographic screening, particularly for high-risk and preterm neonates, to enhance early detection and management of congenital heart disease. Keywords: Neonates, Congenital Heart Disease, Echocardiography, Clinical Examination, Diagnostic Accuracy, Saudi Arabia.10 0Item Restricted DEVELOPMENT OF NOVEL PMMA NANOCOMPOSITES AS LIGHTWEIGHT SHIELDING MATERIALS FOR GAMMA AND X RADIATION(Saudi Digital Library, 2026) ALMUTERY, AML AIED S; ALMUTERY, AML AIED SDespite the effective use of ionizing radiation in the medical field, radiation exposure remains a health hazard and poses threats to human life. In turn, this requires the development of radiation shielding materials. A radiation shield is primarily composed of lead due to its physical and mechanical properties, but lead might be toxic in the case of dust on the surface of lead objects. Polymer-based radiation shields can be utilised in the radiation shielding field due to their excellent physical and chemical properties, ease of fabrication, low manufacturing costs, and toughness. Also, their radiation shielding properties can be improved by using high atomic number fillers. The development of lead-free poly(methyl/methacrylate) PMMA-based nanocomposites reinforced with the following nanoparticles is the focus of this study: bismuth oxide magnesium oxide composites (Bi2O₃:MgO), bismuth oxide-silicon oxide composites (Bi2O₃:SiO₂) and magnesium oxide-silicon oxide composites (MgO:SiO₂) for gamma and X-ray shielding. Despite the addition of nanoparticles, PMMA's chemical stability is confirmed by the fourier-transform infrared spectroscopy's (FTIR) lack of new absorption bands in1000–4000cm-1 spectrum. The X-ray diffraction (XRD) with discrete peaks of crystallinity that correspond to Bi2O₃, MgO, and SiO₂ fillers showed that the PMMA matrix was amorphous, indicating a successful composite production. The scanning electron microscopy (SEM) study showed an equal dispersion of the nanoparticles up to 20 weight percent, whereas a tiny lump was seen at higher loadings. The optical properties were investigated with the help of a UV–Visible Spectrophotometer. The results for the optical properties showed that when the nanocomposites content was increased in the PMMA matrix the Urbach energy (∆E), refractive index (n) increased, while the energy optical band gap (Eopt) registered a decrease in both electron transition direct and indirect. Pure PMMA had a density of 2.72 g/cm3, while sample PMMA/25 wt% Bi2O3:MgO had a density of 3.63 g/cm3. Due to increased photon-matter interaction, the optical band gap of the highly loaded composites increased from 4.64 eV in the pure PMMA to 5.56 eV. At 662 keV, the linear attenuation coefficient (LAC), one of the radiation shielding tests, rose from 0.20 cm-1 for the pure PMMA sample to 0.28 cm-1 for PMMA/25 wt% Bi₂O₃:MgO, whereas the corresponding HVL dropped from 3.36 cm to 2.45 cm. Among other samples, PMMA/25 weight percent Bi2O3:MgO had the best shielding capability, with a radiation protection effectiveness value near that of lead at a diagnostic range. Focus on surface functionalization of the nanoparticles should be examined in future studies as well as multilayer composite designs, and full biocompatibility and mechanical assessments for wearable radiation shielding applications.15 0