United Arab Emirates University
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UNITAL KADISON-SCHWARZ TYPE OF MAPS
Get PDFQuantum entanglement is an important phenomenon in quantum information theory; its uses range from quantum teleportation and quantum cryptography to solving classical communication problems. One of the issues concerning entanglement is the classification of mixed states into separable states. Positive maps define affine mappings between sets of states of C∗algebras, and have been used to develop a separability criterion for quantum states. Completely positive maps are insensitive to entanglement detection, a weaker notion of positivity is thus needed to detect them. This condition that is stronger than positivity but weaker than complete positivity is given by the Kadison-Schwarz (KS) inequality. We introduce the underlying algebra of the Pauli matrices to describe unital KS type of maps on 2(C). The conditions for positive, unital maps to be KS operators are derived, and a non-trivial example of such unital KS operators is provided. This is done through an analysis based on specifying particular parameters of our unital KS mapping
IMPROVING EARLY DESIGN PROCESSES WITH THE USE OF BIM AND VR TECHNOLOGIES IN THE GCC CONSTRUCTION INDUSTRY
Get PDFThe early stages of construction projects play a crucial role in determining the outcome of the entire project life cycle. However, conventional early design practices have been facing significant challenges and limitations in recent times. These challenges include a lack of coordination among various disciplines, communication gaps, and poor decision-making. Unfortunately, these challenges often lead to increased costs, project delays, and change orders. To tackle these challenges, it is essential to adopt the latest technological advancements in the construction industry. This is especially important given the complexity of modern construction projects and the rapid construction growth. One of the most significant technological advancements in the Architecture, Engineering, and Construction (AEC) industry is Building Information Modeling (BIM). BIM technology provides powerful digital information management capabilities and analytical visualization experiences throughout the entire project life cycle. With BIM, stakeholders can have access to accurate and detailed information about the project, enabling them to make informed decisions. One of the most promising BIM-associated technologies is virtual reality (VR), allowing teams and stakeholders to evaluate their decisions through an interactive and immersive virtual environment before the construction stage. Adopting BIM technology with the support of Virtual Reality (VR) has the potential to revolutionize the construction industry processes by providing a collaborative platform for all stakeholders to work together thus reducing the risk of change orders and project delays and improving the overall project outcome. Despite the acknowledged benefits of these technologies, limited research has been conducted on their integration and impact on construction processes, especially in the Gulf Cooperation Council (GCC) Countries, where technology adoption in the construction industry remains slow. As a result, this study seeks to explore the potential benefits of BIM and VR technologies during the early design stages of construction projects. To achieve this goal, a comprehensive questionnaire survey is conducted among professionals in the built environment to identify specific applications and the impact of implementing these technologies on the overall construction project life cycle. The research findings indicate that BIM and VR technologies can play a crucial role in enhancing the early design stage of construction projects. In particular, these technologies can facilitate collaboration among stakeholders and reduce design conflicts, leading to enhanced early design stage performance
HEAD IMPACT MEASUREMENT USING PIEZOELECTRIC SENSORS
Get PDFThe importance of safety measures cannot be overstated, especially when it comes to protecting the human head. Head injuries can have severe, life-altering consequences, as the head is crucial for controlling the entire body. Unlike machines that store data, the human brain\u27s capacity to retain thoughts and memories can be significantly affected by even a single injury. This thesis introduces a method for predicting the specific area of the head that might be injured during an impact. The prediction is based on the intensity and duration of the impact. The innovation of this thesis lies in the use of piezoelectric sensors. These sensors are highly efficient at transforming mechanical pressure into electrical signals. The system is designed with piezoelectric sensors embedded in a helmet, allowing for detailed monitoring of any impacts. In the initial testing phase, a plastic model replicating a human head was used. A set of four-channel piezoelectric sensors was strategically placed in six different locations across this model to cover the entire head. The purpose of this setup was to predict the point of impact and its duration during testing. Data processing was executed using two methods: the Flexible robust Statistics Data Analysis (FSDA) toolbox for extensive validation, and the Extreme Gradient Boosting (XGBoost) model, employing machine learning for precise impact localization. Where the peak values and duration of the impact are determined using various experiments to help identify the severity and location of the impact
Using Artificial Intelligence for Proctoring Remote Exams: Advantages and Challenges
Get PDFThe COVID-19 pandemic has forced extreme changes in educational practices around the world. Many universities and schools have offered their educational curricula and activities completely via online learning. That is why universities and educational institutions have practiced conducting tests remotely to preserve the safety of their students. Meanwhile, these universities and educational institutions faced the challenge of evaluating the integrity of the remote tests. These institutions have sought, through a number of practices, to verify the identity of students and the reliability of their test performance by using a number of means to ensure that the exams are conducted without fraud. One of those means is the use of the artificial intelligence technology applied by the Saudi Electronic University, represented by AI proctor to monitor tests remotely. This study aims to investigate the advantages of using this technology as well as the challenges that faced its implication from the viewpoint of the examination supervisors at the Saudi Electronic University. The study revealed a number of advantages and challenges. The study made a number of recommendations.
Keywords: Distance education, e-learning, COVID-19; E-exam; Distance exams
INTERNATIONAL CRIMINAL LIABILITY OF LEADERS
Get PDFThe primary objective of this research is to explore and elucidate the concepts, principles, and legal frameworks pertaining to the international criminal liability of leaders, particularly in instances where they contravene established norms and statutes of international criminal law. This endeavor seeks to foster a deeper understanding and appreciation for the enforcement mechanisms underpinning such liability, thereby reinforcing respect for international legal standards. The study delves into the evolution of this principle and examines the contemporary acceptance of the idea that leaders and heads of state can be held accountable before a stable and enduring international criminal tribunal. The notion of international criminal responsibility has transcended theoretical abstraction to become a tangible reality in global affairs, as evidenced by landmark trials such as those held in Nuremberg, Tokyo, the Courts of the Former (Yugoslavia, and Rwanda). Furthermore, the establishment of the Permanent Court of Rome and its jurisprudential frameworks, along with associated legal challenges and barriers, underscores the ongoing evolution of international criminal law. Through rigorous inquiry and analysis, this research endeavors to offer viable solutions and insights that may contribute to the ongoing development and refinement of international legal norms and mechanisms
PREVALENCE AND RISK FACTORS OF HIKIKOMORI IN YOUNG ADULTS IN THE MIDDLE EAST
Get PDFHikikomori, a form of severe social withdrawal that can occur without the presence of any other psychological disorder, was once thought to be a Japanese culture-bound phenomena. However, studies have emerged from several parts of the world showing that this may be a global issue. Extant literature suggests associations between hikikomori and behavioral addictions such as gaming addiction and problematic social media use (PSMU). Since there is a relative paucity of research examining this phenomenon in the Middle Eastern context, this study aimed to determine the prevalence and risk factors of hikikomori in young adults of the Middle East. It also had the objective of studying loneliness as a potential mediator between hikikomori and two types of problematic behaviors (gaming and social media use). The study employed a cross-sectional correlational design, collecting a sample of 220 participants residing in Middle Eastern countries (Mage = 21.49 years, SD = 3.31) using a mixture of convenience and snowball sampling. SPSS was used to investigate demographic details, run a hierarchical regression, and Process Macro was used to perform a mediation analysis with loneliness as a single mediator. Results showed that 57.27% of the sample was at high risk of hikikomori. Notably, passive social media users demonstrated significantly greater hikikomori-like traits compared to active users. Furthermore, hikikomori-like traits exhibited significant positive associations with problematic gaming, PSMU, and loneliness. Mediation analysis unveiled loneliness as a significant mediator between problematic gaming and hikikomori-like traits (β = .55, SE = .11, 95%CI .33, .77), as well as between PSMU and hikikomori-like traits (β = .33, SE = .14, 95%CI .04, .62). These findings suggest that interventions targeting behavioral addictions such as problematic gaming and PSMU, or interventions addressing loneliness, hold promise in alleviating symptoms of social withdrawal
FRICTION STIR WELDING OF TUBE-TO-TUBESHEET AND SPOT JOINTS FOR VIRGIN AND RECYCLED THERMOPLASTIC MATERIALS.
Get PDFThermoplastic materials are becoming popular, due to their chemically inert and anti-fouling properties, for use in industrial heat exchanger applications involving heating/cooling of highly reactive fluids like acids. A novel nonconventional joining framework, based on the friction stir welding (FSW) technique, is developed to create high-quality thermoplastic tube-to-tubesheet joints (TTJs). The proposed technique has applications in the thermoplastic shell-andtube heat exchanger and piping industries (as flange-to-pipe joints). The primary objective is to study the feasibility of the FSW technique for developing thermoplastic TTJs, followed by optimization of the process parameters and detailed material characterizations. This work used workpieces (tube, tubesheet) made of carbon black reinforced high-density polyethylene. The effect of different FSW parameters (dwell time, plunge depth, rotational speed, and tube protrusion) on the tube pull-out behavior was studied. The FSW technique showed capabilities at a wide range of operating conditions. The macroscopic and microscopic (SEM-based) fractographic studies suggest that the FSW joints can fail in a ductile, brittle, or mixed manner, depending on the FSW conditions used. The DSC results showed no significant crystallinity changes of the weld material. The TGA results showed no significant thermal degradation of the weld material. The FTIR analysis indicated possible oxidation of the weld material. The capability to form TTJs with high leak path, high load bearing capacity, and no significant material degradations makes the FSW technique suitable for thermoplastic shell-and-tube heat exchanger applications. Further, as a second objective, the effect of adhesive reinforcement and radial clearance (RC) on the development of FSW-based thermoplastic tube-to-tubesheet hybrid joints (TTHJs) was investigated. The FSW technique provides higher load bearing capacity (326 N (0.0 RC), 517 N (0.5 mm RC)) than adhesive joints (226 N (0.0 RC), 206 N (0.5 mm RC)). For 0.0 RC, the adhesive reinforcement improved the load bearing capacity of hybrid joints by 15.6% compared to FSW joints. On the contrary, for 0.5 mm RC, the adhesive reinforcement negatively impacted the load bearing capacity and reduced it by 40.6%. The FSW technique with 0.5 mm RC provided a higher leak path (along with a high load bearing capacity) of 77% remaining tubesheet thickness (\u3e tube thickness) compared to that of 46.6% (\u3c tube thickness) achieved at 0.0 RC. However, the adhesive reinforcement can enhance the leak path of 0.0 RC FSW joints to around 100% remaining tubesheet thickness (\u3e tube thickness) by introducing the adhesive material at the tube-sheet interface. There is also a real demand for sustainable lightweight thermoplastic structures (like thermoplastic heat exchangers) because of growing environmental concerns. One important solution is developing structures through recycled scrap/waste thermoplastic materials. As a third objective, the lap-joint configuration friction stir spot weldability of recycled thermoplastics was studied, to help with analyzing the potential of friction stir-based welding techniques towards developing these sustainable structures. The combined behavior of recycling-welding procedures is investigated, as they may cause degradations; to ensure that the base thermoplastic polymer\u27s chemical, thermal, and mechanical properties are retained. In this work, scrap laban bottles made from HDPE material are used. The highest lap-shear load of 1528 N was achieved at the optimum welding conditions of 1600 rpm rotational speed, 1 mm plunge depth, and 60 s dwell time. Fractographic studies (macroscopic and SEM-based) suggested four types of fracture morphologies depending on welding conditions used. The DSC results showed no significant differences in melting temperature and crystalline content of the polymeric material. The TGA tests showed no significant thermal degradations. The FTIR analysis of all the samples (bottle, recycled sheet, weld material) exhibited characteristic HDPE peaks. All these results suggest that combined welding-recycling processes had a minimal impact on the polymeric structure. Thus, friction stir spot welding (FSSW) technique joins recycled thermoplastic scrap/waste materials with high lap-shear load and without any significant polymer degradations
ORGANIC-BASED NUTRIENT SOLUTIONS FOR SUSTAINABLE VEGETABLE PRODUCTION IN A ZERO-RUNOFF SOILLESS GROWING SYSTEM
Get PDFAs the adoption of soilless production systems escalates to meet the rising demand for safe and healthy fresh produce, the growing environmental awareness and consumer’s preference for sustainable production systems are stimulating the reduction of synthetic inputs. A greenhouse study using an auto-pot zero-runoff hydroponic system and lettuce (Lactuca sativa L.) as a model vegetable crop was conducted to evaluate the potential of substituting synthetic fertilizer nutrient solutions (NS) with organic-based NS. The use of organic NS resulted in lettuce plants with fewer leaves and a smaller leaf area, plant height, stem diameter, and fresh biomass compared to those grown with inorganic fertilizer. Among the organic NS used, NS B from fish farm waste (159.8 g) and E from plant sources (157.9 g) ensured crop yield performance slightly lower than the inorganic fertilizer NS (175.1 g), but higher than the other humic acid based-organic NS C and D. However, total chlorophyll (0.81 and 0.93 mg/g. respectively) and carotene (0.23 and 0.26 mg/g, respectively) levels were higher in organically grown lettuce compared to the control (0.95 0.17 mg/g, respectively). Furthermore, plants grown organically in NS C and D had greater phenolic levels (3.36 and 3.22 g/100 g, respectively) as compared to those nourished with inorganic fertilizer (2.28 g/100g). All organically grown lettuce plants had lower levels of Ca, K, and Mg, and higher P compared to the control. Moreover, all organic NS resulted in lower leaf nitrate levels (ranging from 3.2 to 8.7 mg/kg) compared to the inorganic NS (259.8 mg/ kg) based on dry weight. Our findings suggest that organic liquid fertilizers may enable the sustainable production of safe, nutritious, and healthy vegetable crops. However, further study is required to improve and overcome the limitations of such systems
SYNTHESIS, CHARACTERIZATION AND BIOLOGCAL EVALUATION OF SAFRANAL-LOADED METALORGANIC FRAMEWORK NANOSTRUCTURES
Get PDFLiver cancer remains a primary worldwide health concern, necessitating the development of innovative and effective treatment options. In this study, we present a biocompatible iron-based metal-organic framework (Fe-MOF) consisting of iron ligands connected by terephthalate linkers loaded with safranal, a natural biomolecule extracted from stigmas of Crocus Sativus flower (also known as saffron), a therapeutic intervention with dual efficiency. This compound not only meets the demand for improved liver cancer therapies but also exhibits antibacterial properties against Escherichia coli and Lactobacillus. The synthesis stage of the study focuses on preparing MIL-88B(Fe) and loading safranal into/onto its structure. The material\u27s composition and purity are validated through various characterization techniques, including XRD, FTIR, TGA, and N2-adsorption. Furthermore, the morphology and uniformity are assessed using the SEM-EDX approach, while the successful loading of safranal is confirmed through the NMR technique. The potential of MIL-88B(Fe) and loaded-MIL88B(Fe) as promising anticancer/antibacterial agents is highlighted by their substantial inhibitory impact on the growth of HepG2 cells and the examined bacterial strains. The present findings pave the way for developing innovative multifunctional agents with potential applications in biotechnology
GA-GESRGAN: Document Images Super Resolution using Gabor Filters, ESRGAN Models and Genetic Algorithms
Get PDFIn the last decade, we have witnessed significant progress in image super-resolution, thanks in particular to the emergence and improvement of deep learning models, which can adapt to the complexity of tasks and improve image quality. This article presents a novel approach to image super-resolution GA-GESRGAN to enhance the quality of document images through a multi-step methodology. Initially, document images are processed using Gabor filters to extract features across various spatial frequencies. These extracted features are then utilized to train Enhanced Super-Resolution Generative Adversarial Network (ESRGAN) models. Once improved images are obtained through ESRGAN models, a Genetic Algorithm combines these results effectively. This innovative methodology highlights the synergy between traditional image processing techniques, deep learning models, and advanced optimization algorithms, ultimately leading to significant improvements in document image quality. The results demonstrate the potential of this approach