Saudi Cultural Missions Theses & Dissertations
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Item Restricted Effect of Angulation Between Multi-Unit Abutments on Accuracy of Photogrammetry Scanning(University of Illinois Chicago, 2025) Andejani, Abdulelah; Shonberg, David; Harlow, Rand; Yang, BinA study to comparing the accuracy between analog elastomeric impressions and photogrammetry scanning utilized for full-arch implant supported prosthesis was conducted to investigate the clinical implications of misfit values in terms of 3-dimentional deviation and angular deviation. Furthermore, the effect of increased inter-abutment angulation between multiunit abutments was evaluated; the angulations evaluated were zero-degree, 10-degree, and 20-degree inter-abutment angulations. Using a reverse engineering software, and utilization of reference best-fit algorithms, conventional impression technique, PIC Dental Photogrammetry technique and ICam4D photogrammetry technique were compared. The accuracy determined via the 3-dimentional deviation and angular deviation were analyzed for each technique and for each of the three inter-abutment angulations. Conventional impressions scans exhibited lower deviation values compared to both photogrammetry techniques. Additionally, the increased inter-abutment angulation did not negatively affect the accuracy of the conventional impression samples. However, increased inter-abutment angulation had a variable effect on the accuracy of the photogrammetry scanning. The study emphasized that traditional impressions are more accurate for recording implant positions in full-arch implant-supported prostheses, while the photogrammetry techniques showed comparable accuracy influenced by the inter-abutment angulation. Differences observed between groups and other literature cited, can best be explained by the superior control of settings of the conventional impression technique, including setting time, polymerization shrinkage and thermal contraction of the dental materials used.12 0Item Restricted Detecting abuse of cloud and public legitimate services as command and control infrastructure using machine learning(Cardiff University, 2024) Al lelah, Turki; Theodorakopoulos, GeorgeThe widespread adoption of Cloud and Public Legitimate Services (CPLS) has inadvertently created new opportunities for cybercriminals to establish hidden and robust command-and-control (C&C) communication infrastructure. This abuse represents a major cybersecurity risk, as it allows malicious traffic to seamlessly disguise itself within normal network activities. Traditional detection systems are proving inadequate in accurately identifying such abuses. Therefore, this thesis is motivated by emphasizing the urgent need for more advanced detection techniques that are capable of identifying the C&C activity hidden within legitimate CPLS traffic. To assess the extent of the cyber threat of abusing CPLS, this thesis presents an ex- tensive Systematic Literature Review (SLR) encompassing academic and industry lit- erature. The review provides a comprehensive categorization of the attack techniques utilized to abuse CPLS as C&C infrastructure. The open problems uncovered through the SLR motivate this thesis to propose a novel Detection System (DS) capable of identifying malware that abuse CPLS as C&C communication channels. Furthermore, to evaluate our system robustness against attempts to evade detection, this thesis intro- duces the Replace Misclassified Parameter (RMCP) adversarial attack. The proposed detection system leverages Artificial Intelligence (AI) techniques, combining static and dynamic malware analysis methods to accurately identify CPLS abuse. The effective- ness of the proposed system is validated through extensive experiments, demonstrating its ability to detect novel and sophisticated attacks that evade traditional security measures. The outcomes of this thesis have significant implications for enhancing the security of cloud environments, contributing valuable knowledge and practical solutions to the field of cloud security.26 0Item Restricted Enhancing the quality and standard of research in Saudi Arabian universities: Selection and use of research methods at doctoral level: An investigative study on the use of research into statistical methods(University of glasgow, 2024) Abohiamid, Manal; McMahon, Margeryhis study investigated the selection and use of research methodologies at doctoral level, with particular emphasis on the use of statistical practices in research and with a focus on the Saudi Arabian context. There are misapplications in certain studies when analysing the statistical data, and some of these inaccuracies come from using improper management and suitable statistical methods at the analysis stage, contributing to misleading research conclusions. A key question was ‘How do academics and PhD students from Education departments in a selected university in Saudi Arabia and a university in Scotland/United Kingdom, from different educational backgrounds, view their readiness, selection, and utilization of statistical methods in PhD research?’. The accurate use of Statistics is critical in academic research, Statistics provide a methodical and objective approach to data analysis and interpretation, allowing researchers to make meaningful conclusions and uncover noteworthy patterns. Thus, a study acquires credibility and assures the validity of its findings by using accurate statistics, allowing policymakers and stakeholders to make educated decisions and perform targeted adjustments that enhance every aspect of society. This study examined PhD students' perceptions of their preparedness for statistical analysis, as well as their statistical and mathematical skills. Currently in Saudi Arabia, a programme of development: Vision 2030, is being implemented and so an aim of this study was to show why reforms are needed in Saudi Arabia's education system and why future university students should have sufficient Mathematical understanding to maintain the PhD researcher's basic knowledge base (Mathematics and Statistics). This was accomplished by sending a questionnaire to PhD students in SA and UK and conducting interviews with Statistics lecturers for postgraduate students in Saudi Arabia. The study found there is data analysis problems, such as inaccurate statistical technique application, a lack of pre-existing Mathematical expertise, wrong data processing, and incorrect result analysis. To increase the accuracy of statistical methods employed in PhD research, the study recommends that qualified statisticians, Statistics centres, and quality Mathematics and Statistics material be developed in the KSA. Furthermore, the research showed the significance of developing educational cadres in Statistics, developing the literacy pathway in schools in Mathematics, and making advanced Statistics courses necessary for postgraduate students in order to improve the quality and credibility of research undertaken, and the significance of students having a mathematical foundation in the Kingdom of Saudi Arabia25 0Item Restricted Measuring The Quality of Wikipedia Articles Among Different Topics(Saudi Digital Library, 2023-11-23) Aljohani, Thamer; Niesen, JitseWikipedia, a globally famous online encyclopedia, offers millions of articles across diverse topics. Its open editing policy, allowing contributions from volunteers, has made it a valuable resource. However, its reliability has been questionable, particularly in academic circles. To enhance the understanding of Wikipedia’s quality, and due to the difficulty of the assessment of quality in Wikipedia’s approach, this study presents an innovative approach to evaluate article quality. This study aims to create a quantifiable simple model based on measurable attributes, such as the length of articles, the number of references, and the number of edits. This model facilitates the calculation of article quality and subsequent assignment of quality classifications. As a result, the model proposed in this study shows an approximate accuracy equal to a random forest model which is considered a complex model. Furthermore, the research explores variations in article quality across various topics, shedding light on topics where high-quality content is prevalent and areas that require improvement. Data was collected from the Wikipedia API, and based on these measurable features, quality assessments were made. The findings indicate that Astronomy topics have a higher level of quality, while Language topics have a lower proportion of high-quality topics. These findings suggest that the attributes used to measure quality in this study are sufficient and efficient for assessing article quality on Wikipedia. Moreover, the study highlights the articles that need the experts to focus their efforts on improving articles related to topics such as Language, Business, or Mathematics to enhance the overall quality of content in these topics.10 0Item Restricted Learning Outcomes of the Simultaneous Exposure to Two Arabic Varieties by English L1 Learners of Arabic as an L2 at Different Stages of their L2 Development(University of Michigan, 2023-07-12) Alshehri, Mohammed Salem; Alhawary, MohammedThe efficacy of the “integrated approach,” which calls for the simultaneous integration of two varieties in teaching Arabic as a second language (L2), has not yet been rigorously examined, and the very few available studies suffer from many methodological limitations. The current study sought to bridge this gap in the literature by comparing the language output (in terms of fluency, accuracy, complexity, and overall proficiency) of 57 English first language (L1) learners of Arabic as an L2, belonging comparably to two groups: the first consisted of those instructed in Modern Standard Arabic (MSA) and Egyptian Arabic (EA) simultaneously, the integrated program group (IPG), and the second consisted of those instructed in MSA only, the unintegrated program group (UIPG). The participants of both groups were further divided cross-sectionally based on their three proficiency levels: first year, second year, and third year. Their performance was additionally compared to that of a control group (CG) consisting of nine native speakers of EA. Spontaneous obligatory-in-context data were elicited from the participants who performed three oral picture-based description tasks: two narrative tasks and one manipulation task. Fluency was measured by counting words produced per minute (W/M). Accuracy was examined in their production of the past tense, present tense, past negation, and verbal present negation. Complexity was measured by their error-free production of the subjunctive and cause–effect subordinations. The overall proficiency was gauged by adding up the scores attained in the above-mentioned three constructs. The findings revealed that both L2 groups produced comparable W/M when narrating past and present events. However, in other areas examined, the UIPG maintained a significant advantage over the IPG: (a) at the first-year and second-year levels on the past tense, (b) at the third-year level on the present tense, (c) at the first-year and third-year level on the past negation, (d) at the second-year level and (near-significantly) at the third-year level on the verbal present negation, (e) at the second-year and third-year levels on the subjunctive and cause–effect subordinations, and (f) at the second-year and third-year levels on the overall proficiency. The advantage of the UIPG over the IPG was further supported by the within-group analyses. The UIPG improved significantly in the long run—particularly at the third-year level—in their fluency, in all target structures (except for the past tense with the third-person singular feminine form and past negation), and in their overall proficiency. In contrast, the IPG did not show any significant improvement—particularly from the first-year to third-year levels—in their fluency, in all target structures in which MSA and EA diverge, and in their overall proficiency. Additionally, only the third-year UIPG participants were statistically on par with the CG in their accuracy on the past tense and present tense (in the third-person singular masculine context), as well as the verbal present negation. The strong implication of these findings is that the simultaneous exposure to two varieties from the outset, without sufficient recycling, visual presentation, and explicit instruction of their structures in the input, is not beneficial to Arabic L2 learners and might be detrimental to their developmental acquisition paths. Such an instructional practice can cause linguistic dissonance, hinder comprehension, and obstruct facilitative L1 transfer. Thus, it is pedagogically recommended to initially teach one variety for the first 2 years of the learning process.38 0