United Arab Emirates University
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MAPPING AND ANALYZING URBAN GROWTH IN THE ABU DHABI METROPOLITAN USING GEOSPATIAL TECHNOLOGIES INTEGRATED WITH MACHINE LEARNING
Full text linkUrbanization is happening at a rate twice the increase in population on a worldwide scale. This has great environmental and social impacts, along with large impacts on regional climate and one of the reasons for this is the ever-continuous change of land use and land cover. The availability of high-resolution satellite imagery in addition to the advancements in geospatial technology allow mapping of LULC changes to be done accurately, efficiently and covering wide areas. This thesis studies the urban Land Use and Land Cover Change (LULCC) that happened in Abu Dhabi city for the last 3 decades by utilizing geospatial technologies integrated with machine learning. The goal of this research is to utilize Support Vector Machine (SVM) to model the urban LULCC that occurred in Abu Dhabi metropolitan area between 1990 and 2022. Landsat imagery of the years 1990, 2000, 2014 and 2022 were retrieved to analyze the changes. The analysis split the Land Use into two main classes: urban and non-urban to better understand the change in urban land that occurred. Post-Classification Comparison (PCC) was chosen to map the change that occurred between the consecutive years as well as for the entire study period. The area of urban land was extracted from each of the maps and presented to clearly quantify the amount of change that occurred between each period.The results from this research aim to demonstrate the ability of supervised machine learning in modelling the urban growth in Abu Dhabi. It also aims to visualize the change that occurred over the study period and present a temporal model which can both offer valuable insight to urban planners and policymakers for the future
WIDE LOCK-IN ENERGY HARVESTING FROM VORTEX-INDUCED VIBRATIONS OF A DEFORMABLE CYLINDER
Full text linkEnergy harvesting from ambient sources has gained attention due to increasing energy demands. Despite VIV-based harvesters showing significant potential, their lock-in region, where significant power is generated, is narrow. Given the continuously varying ambient conditions of fluid currents, harvesters can easily fall into de-synchronization, yielding low energy output. Existing solutions like tunable masses or multiple degrees of freedom systems increase complexity and weight, limiting practical applications. This work introduces a novel variable diameter cylinder mechanism—a practical technique that actively tunes the cylinder’s geometry in real time to enhance energy harvesting efficiency from VIV. The mechanism employs an expanding pulley system that deforms the elastic circular cylinder radially, dynamically altering its diameter to adjust key non-dimensional parameters governing VIV. This real-time adaptability counteracts ambient fluctuations, significantly widening the lock-in range. The cylinder incorporates a piezoelectric transducer, and the fluid-structure-piezoelectric interaction problem was analyzed numerically to determine the cylinder motion, voltage, and power output. A partitioned Lagrange-Eulerian approach was employed, coupling an FVM fluid solver with a custom-coded structural piezoelectric solver via the preCICE library which enables data mapping and exchange between solvers at run time. The analysis was conducted for different diameter profiles, and the results showed an enhancement in the harvester synchronization width and maximum amplitude by 70% and 117%, respectively, compared to the constant diameter case. Additionally, a 113% increase in peak voltage was achieved, and more than 8 times greater power was generated. The analysis also showed the effect of load resistance on harvesting performance, and the varying diameter cases demonstrated resilience against the shunt-damping effect. The proposed control technique is versatile, as it can be used for VIV suppression as well as energy harvesting applications
Child Empowerment and Safeguarding in the UAE: The Role of Picturebooks for Emirati Children
Full text linkThis paper presents a reflective ethnography documenting the creation and use of picturebooks in the United Arab Emirates (UAE), aimed at supporting the safeguarding of children within English Language Teaching (ELT) contexts for primary and lower secondary students. It explores the collaboration between an author and an illustrator in developing books that align with the principles of Wadeema’s Law, the Child Protection Law of 2016. These picturebooks are designed to safeguard children’s psychological and emotional well-being, facilitate bibliotherapy, and promote learning across curricula. They serve as informational, inspirational, and discussion texts that contribute to raising awareness of child rights, particularly in the context of Emirati culture and values. Our paper discusses five picturebooks, three of which were published by the UAE Ministry of Community Development. Through this collaborative ethnography, the study focuses on the development, content, and implementation of these books as pedagogical tools to foster discussions on child safeguarding and support the broader objectives of child protection in the UAE
DISTURBANCE OBSERVER IN GRID-SIDE CONTROLLER FOR WAVE ENERGY CONVERTERS
Full text linkA typical Permanent Magnet Linear Generator (PMLG)-based ocean wave energy system consists of an electrical generator, a Machine-Side Converter (MSC), a Grid-Side Converter (GSC), a DC-link capacitor, and a passive filter—such as an L filter or LCL filter—to connect the GSC to the grid. The main objective of this work is to control the GSC using a disturbance observer-based control technique to inject constant power and balanced current into the grid under both balanced and unbalanced grid conditions.This thesis presents a controller for the converter that integrates a state-feedback controller with a disturbance observer. The feedback controller stabilizes the nominal closed-loop system, while the disturbance observer functions as a servo-compensator to mitigate the impact of model uncertainties and unknown disturbances. Robustness—i.e., the ability to handle uncertainty and noise effectively—is one of the key performance criteria in evaluating the proposed control method.Therefore, this work begins by deriving an averaged wave energy converter (WEC) model, which is then simulated in MATLAB/Simulink. Additionally, the controller model is developed and derived in the Stationary Reference αβ Frame.Simulation tests are carried out to validate the effectiveness of the proposed control technique using MATLAB, considering realistic scenarios and appropriate control settings. The results indicate that the proposed control strategy achieves satisfactory steady-state and transient performance under balanced grid voltage conditions; however, certain limitations are observed in the presence of unbalanced grid voltage
EFFECT OF FIBONACCI-INSPIRED MULTI-LAYER ALUMINUM SHEETS UNDER DOUBLE-NOSE PROJECTILE IMPACT
Full text linkThis research examines the ballistic performance of multi-layered Aluminum 2024 sheets designed with Fibonacci-inspired spacing patterns when subjected to double-nose projectile impacts. Through a numerical simulation, five configurations were studied: a monolithic reference plate (L0) with 0.82 mm thickness, and four multi-layer configurations (L1 to L4), all maintaining a constant total thickness of 1.74 mm. Three projectile types were considered Blunt-Conical (BC), Conical-Blunt (CB), and Blunt-Blunt (BB). Among these, the L1 configuration (two layers separated by a 0.1 mm gap) consistently offered the best ballistic resistance, outperforming more complex arrangements. As layer complexity increased from L1 to L4, overall performance declined, with L4 behaving similarly to the thinner monolithic L0, despite its greater number of layers and total material. Efficiency analysis highlighted that adding more interfaces brings diminishing returns; the Interface Efficiency for L4 dropped to just 17% of that seen in L1. Interestingly, the CB projectile showed strong compatibility with the L2 configuration, suggesting a geometry-specific interaction. Further evaluation of energy absorption, damage progression, and velocity ratios confirmed that reducing individual layer thickness below ~0.3 mm leads to premature failure, nullifying the advantages of additional interfaces. Overall, this study challenges the common assumption that adding more layers always enhances protection. Instead, it highlights the importance of keeping each layer thick enough and placing interfaces strategically, rather than simply increasing the number of layers
ENGINEERING BIO-BASED POLY (ETHYLENE FURANOATE) BLENDS AND NANOCOMPOSITES
Full text linkThe growing demand for sustainable materials has directed attention toward bio-based polymers such as poly(ethylene furanoate) (PEF), a 100% bio-derived alternative to PET. While PEF offers excellent gas barrier and thermal properties, its limited mechanical strength restricts its use. This study explores polymer blending and nanocomposite strategies to enhance PEF’s mechanical and electrical performance.Blending PEF with linear low-density polyethylene (PE) using reactive compatibilizers (SEBS-g-MA, PE-g-MA) significantly improved ductility and tensile toughness. Interfacial reactions between PEF and compatibilizers transformed the blend morphology, resulting in improved flexibility suitable for packaging applications.Electrically conductive composites were developed by localizing graphene nanoplatelets (GNP) at the PEF/PE interface. Mixing parameters and compatibilizer presence affected GNP placement and conductivity. Notably, GNP localization at the interface yielded a low percolation threshold (0.97 vol%), and 3D conductive networks were confirmed through conductivity modeling.Additionally, PEF/polylactic acid (PLA) blends with carbon nanotubes (CNT) were studied. Across varying PEF/PLA ratios and CNT loadings, conductivity improvements were noted, especially with simultaneous mixing. CNT also promoted partial miscibility, evidenced by uniform morphology and suppressed phase separation.Overall, this work enhances understanding of PEF-based blends and nanocomposites, offering pathways to develop sustainable, high-performance materials for packaging and electronics
The Transition of Mathematics Learners from 9th to 10th Grade While Acquiring 21st-Century Skills
No full textThis study aimed to examine the transition of mathematics learners from the 9th grade (intermediate) to the 10th grade (secondary) in terms of incorporating 21st-century skills in mathematics textbooks. The researcher used a descriptive analytical method and content analysis cards to assess the study unit questions in both 9th and 10th-grade textbooks for the 2023-2024 academic year. The analysis focused on critical thinking and creativity skills, using 24 indicators.
Results for the 9th-grade textbooks showed low inclusion of inductive (10.30%) and deductive reasoning (17.86%) skills, with a moderate inclusion of analysis skills (65.97%). Innovation and creativity skills, such as originality, flexibility, and fluency, had a 0% inclusion rate, and the expansion skill was included at a very low rate of 5.84%. In the 10th-grade textbooks, inductive reasoning was included at 23.20%, deductive reasoning at 40.40%, and analysis skills at 32%, all at low to moderate levels. Creativity skills were again underrepresented, with flexibility and fluency at 0%, originality at 0.4%, and expansion at 4%.
The study recommends improving mathematics textbooks by incorporating higher levels of 21st-century skills, particularly critical thinking, creativity, and innovation, to enhance students\u27 skill acquisition.
Keywords: 9th Grade, 10th Grade, 21st Century Skills, Acquisitio
THE CRIMINAL LIABILITY PROVISIONS OF ARTIFICIAL INTELLIGENCE (AI) ACTIONS
No full textThis study aims to define the concept and levels of artificial intelligence (AI) to understand its legal nature, personality, and impact on criminal liability. It analyzes the current legal frameworks and examines existing legislation related to AI, assessing their ability to address issues concerning criminal responsibility for the actions of these systems. The study begins by defining the precise concept of criminal liability to understand how it can be applied in a technological environment. It then defines AI and explores its legal nature, to analyze current frameworks and evaluating how effectively they deal with questions of criminal accountability for AI’s actions. The study also discusses the adequacy of traditional concepts of criminal liability in addressing crimes that may be committed by AI systems. The research concluded with several key findings, most notably that the mental element (mens rea) of traditional crimes does not align with the nature of autonomous AI systems capable of self-learning and independent decision-making. It also found that distributing responsibility among different parties (developers, manufacturers, owners, and users) is challenging, particularly when fault is unclear or complex. Accordingly, the study recommends that legislators establish a specific legal classification for AI systems that considers their dual nature—both tangible and non-human software-based—so that they are neither treated as mere “objects” nor granted full legal personality. Instead, a special legal status should be created to reflect their technical characteristics and define the scope of liability arising from their use. Additionally, new national legislation should be enacted to regulate the criminal responsibility of AI systems, particularly self-driving vehicles, including clear definitions of such systems and a classification of possible types of liability
ANTECEDENTS AND EFFECTS OF USE OF SOCIAL MEDIA BY SMALL BUSINESS FIRMS IN THE UNITED ARAB EMIRATES: INSIGHTS FROM DUBAI
No full textThe utilization of social media by small and medium-sized enterprises (SMEs) to enhance their business growth and sales promotion has garnered significant attention in both academic and industrial arenas. Thus, several academic inquiries have attempted to identify the most effective ways to equip and incorporate social media technology, as well as applications into small business operations. This study is primarily concerned with the integration of social media technologies to facilitate seamless digital transformation across small business functions and operations. Conversely, research on social media in the UAE has emphasized the advantages for end users, while neglecting to consider the factors that influence organizational adoption and utilization of such technology. To address this research gap, this study investigates the factors that drive small businesses in the UAE to adopt social media technology, taking Dubai as a case study. In the context of Dubai\u27s business networks, this study examines the potential impact of technology-organizational-environmental (TOE) factors on small companies\u27 adoption of social media technology, using the TOE framework proposed by DePietro et al. (1990) and Nunnally and Bernstein (1994). The required data were collected through an online survey completed by 380 participants (e.g., owners, senior managers, and executives) from small businesses in Dubai. By utilizing IBM AMOS 28, the data collected and processed quantitatively by using SPSS. It identified the factors that influence small business use of social media within Dubai and highlighted how advanced ICT infrastructure in the UAE is key to e-business activity and cost-effective operations
EFFECT OF MICROBIAL INOCULATION ON PHOSPHATE AND NITROGEN UPTAKE FROM DRY SOIL BY TWO GRASSES WITH DIFFERENT NUTRIENT ACQUISITION STRATEGIES
No full textOrganic matter and other sources of plant nutritional elements typically enter the soil from its surface, resulting in topsoil having the highest microbial activity, concentration of nutritional elements, and rooting densities. In agricultural systems of the UAE, high ambient temperature triggers rapid evaporation and causes the topsoil to dry. Nutrient uptake from dry soil is very challenging for plants, and topsoil dryness can have a negative impact on plant performance.Beneficial soil microorganisms mediate plant growth by inducing tolerance against abiotic stresses. Arbuscular mycorrhizal (AM) fungi extend a large network of hyphae that helps the plants to acquire water and nutrients from far distances. However, it has also been observed that AM non-host plant species are relatively more common in the most extreme environments like the hyper-arid deserts of the Gulf Region. The reasons for this are not yet well understood. The present study thus compared the response of an AM-host plant, Sorghum bicolor, and a non-host, Cyperus conglomeratus, to inoculation with soil microorganisms and exposure to dry soil. C. conglomeratus is native to the desert ecosystems of the UAE and known to form thick rhzosheaths rather than AM fungal symbioses. Plants of the present study were either or not exposed to dry topsoil for a period of 48 days, and either or not inoculated with soil microorganisms from natural and agricultural soils of the UAE. Two different experiments were conducted, one aiming at assessing P uptake from dry topsoil, and another aiming at quantifying uptake of N.As a result, the present study cannot confirm a positive interaction of C. conglomeratus with soil microorganisms. On the contrary, microbial inoculation reduced the P and N nutritional status of these plants. Our results thus rather suggest that C. conglomeratus is a plant that relies on non-microbial nutrient and water acquisition strategies. This might align with its adaptation to disturbed habitats from which plants, organic matter, and microbial life are largely absent.In both plant species, more than 85 % of root biomass was found in the topsoil, even after a long period of restricted water supply to this part of the soil. This indicates that plants invest new roots in the acquisition nutritional elements from topsoil rather than water from moist subsoil.The present study further confirms the importance of AM fungal symbioses for crop P acquisition from dry topsoil. Previous studies had demonstrated such contributions for isolated and selected AM fungal strains and in rather artificial systems. Our study deployed natural microbial communities found in agricultural and roadside soils in Al Ain and demonstrated that these can increase P uptake from a dry topsoil by around 100 %. There was no contribution of microbial inoculation to N uptake, confirming that AM fungi are primarily a P acquisition strategy and that a contribution to N uptake might only occur in conjunction with symbiotic contribution to P uptake. Field-scale validations of these findings will be crucial to assessing their real-world applicability, solidifying this work\u27s contribution to enhancing food security in challenging climatic regions by harnessing the power of plant-microbe symbioses