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Regioselective Catalytic Synthesis Of Potentially Bioactive 1,3,4-Selenadiazole, Mohamed Ali Mahmoud Dec 2023

Regioselective Catalytic Synthesis Of Potentially Bioactive 1,3,4-Selenadiazole, Mohamed Ali Mahmoud

Theses

Isoselenocyanates have a crucial role as reactants in chemical processes, facilitating the efficient synthesis of significant chemical intermediates and physiologically active chemicals. The utilization of (Z)-2-oxo-N-phenylpropanehydrazonoyl chlorides in a one-step procedure for the synthesis of the core structure of various heterocyclic compounds has been widely explored. This study focuses on the synthesis of 5-arylimino-1,3,4-selenadiazole derivatives through the reaction of isoselenocyanates with various substituted (Z)-2-oxo-N-phenylpropanehydrazonoyl chlorides. The objective is to achieve selective and accurate formation of these derivatives. The derivatives exhibit a diverse range of functional groups on both aryl rings. The synthetic procedure is conducted under ambient conditions, promoting environmental …


Commissioning Of The Uaeu Radio Array And Pilot Low-Frequency Radio Astronomy Studies, Aisha Ali Alnaqbi Nov 2023

Commissioning Of The Uaeu Radio Array And Pilot Low-Frequency Radio Astronomy Studies, Aisha Ali Alnaqbi

Theses

As part of the UAEU Radio Astronomy Pathway Project, a 256-element Ground based Radio Array Facility was deployed at the UAEU. A comprehensive exploration of radio astronomy, and investigations on existing radio arrays, emphasizing low-frequency radio signals and the challenges faced at this range, are crucial for the commissioning phase of the array. A core aspect discussed is the vital role of coaxial cables in preserving the integrity of low-frequency radio signals. To address the electrical length differences between the coaxial cable pairs used to connect the array’s beamformers in the field to the beamformer controllers in the control room, …


An Empirical Study On The Use Of Secure Predictive Analytics For Improving Trade Forecasting In The Uae, Asma Salem Alneyadi Nov 2023

An Empirical Study On The Use Of Secure Predictive Analytics For Improving Trade Forecasting In The Uae, Asma Salem Alneyadi

Theses

Trade contributes to the United Arab Emirates' economic growth. This thesis focuses on trade dynamics in the UAE using Long Short-Term Memory (LSTM) neural networks. The study focuses on both import and export activities, providing understandings into the complex patterns and impacts of international trade on the UAE's economic growth. The research begins by constructing an LSTM model to forecast the UAE's Gross Domestic Product (GDP) through the utilization of historical trade data. We use time series data for imports and exports as key input features. This innovative approach highlights the relevance of trade statistics as a leading indicator of …


Estimating Mars Surface Wind Stress And Dust Lifting Using Reanalyses Based On Emm And Other Spacecraft Observations, Haneen Abouhaligah Nov 2023

Estimating Mars Surface Wind Stress And Dust Lifting Using Reanalyses Based On Emm And Other Spacecraft Observations, Haneen Abouhaligah

Theses

Studying Mars offers insights into terrestrial planet evolution and informs future human expeditions. This thesis examines dust dynamics in Mars’ lower atmosphere, focusing on understanding its weather and climate. We investigate the role of Near-Surface Wind Stress (NSWS) in dust lifting, using six reanalysis datasets, respectively: MACDA, EMARS, OpenMARS, ACS–TIRVIM (ExoMars observations of the MY34 Global Dust storm), EMM1 and EMM2. Following the parameterization approach by Newman et al. (2002a), areas of agreement and discrepancy among datasets were identified. Time series analysis revealed consistent results where datasets overlap temporally. Some differences were expected and shown due to the different Global …


A Smart Chatbot System For Digitizing Service Management To Improve Business Continuity, Asraa Mohammed Albeshr Nov 2023

A Smart Chatbot System For Digitizing Service Management To Improve Business Continuity, Asraa Mohammed Albeshr

Theses

Chatbots, also called digital systems that require a natural language-based interface for user interaction, are increasingly being integrated into our daily lives. These chatbots respond intelligently to voice and text and function as sophisticated entities. Its functioning includes the recognition of multiple human languages through the application of Natural Language Processing (NLP) techniques. These chatbots find applications in various areas such as e-commerce services, medical assistance, recommendation systems, and educational purposes. This reflects the versatility and widespread adoption of this technology. AI chatbots play a crucial role in improving IT support in IT Service Management (ITSM) for better business continuity. …


Impact Of Covid-19 On Security Vulnerabilities Of Learning Management Systems: A Study Towards Security And Sustainability Enhancement, Souheil Abdel-Latif Akacha Nov 2023

Impact Of Covid-19 On Security Vulnerabilities Of Learning Management Systems: A Study Towards Security And Sustainability Enhancement, Souheil Abdel-Latif Akacha

Theses

The rapid adoption of Learning Management Systems (LMSs) like Moodle, Chamilo, and Ilias became essential for online education due to the Coronavirus Disease 2019 (COVID-19) pandemic, revolutionizing online learning while exposing security vulnerabilities. This thesis explores security concerns within these LMSs across different pandemic periods. By analyzing existing patches, security measures, and emerging cybersecurity technologies, recommendations are formulated to enhance LMS security against evolving cyber threats, providing actionable insights for educational institutions to ensure secure online education continuity. The numerical findings highlight the increasing need for proactive security measures in Moodle, the fluctuating nature of vulnerabilities in Chamilo, and the …


Coastal Bathymetry Of The United Arab Emirates Using Satellite-Based Remote Sensing Data, Naser Salem Aldahmani Nov 2023

Coastal Bathymetry Of The United Arab Emirates Using Satellite-Based Remote Sensing Data, Naser Salem Aldahmani

Theses

Bathymetry is the study of the bed under the water's surface, giving us the water's depth. The Thesis will be about studying the coastal area of the UAE by using satellite images that can help access large regions of the UAE Coast. Also, by using a history of 5 years of satellite visible bands and NIR images, we can see the change of depth near the coastal. The benefit of that study will help to build ship baths through shallow water and to go in and out of ports of UAE. Early warnings of the sea level increasing near the …


Enhancing Autism Education: Exploring Interactive Videos And Ai Integration For Effective Teaching, Fatima Ahmed Alraeesi Oct 2023

Enhancing Autism Education: Exploring Interactive Videos And Ai Integration For Effective Teaching, Fatima Ahmed Alraeesi

Theses

This research focuses on enhancing autism education by integrating interactive videos and AI solutions to improve teacher training. As the number of autistic students rises, it becomes crucial for special education teachers to employ effective teaching strategies tailored to individual needs. The most effective teaching methods for autistic students involve understanding the condition and incorporating customized instruction strategies, such as adapting assignments to suit the student's needs, assisting those with difficulty speaking, and employing visual aids for better organization. The proposed solution involves utilizing interactive video technology to train teachers, bridging the gap between research and practical implementation of educational …


Design Modular Command And Data Handling Subsystem Hardware Architectures, Abdullah Alsalmani Jun 2023

Design Modular Command And Data Handling Subsystem Hardware Architectures, Abdullah Alsalmani

Theses

Over the past few years, On-Board Computing Systems for satellites have been facing a limited level of modularity. Modularity is the ability to reuse and reconstruct the system from a set of predesigned units, with minimal additional engineering effort. CDHS hardware systems currently available have a limited ability to scale with mission needs. This thesis addresses the integration of smaller form factor CDHS modules used for nanosatellites with the larger counterparts that are used for larger missions. In particular, the thesis discusses the interfacing between Modular Computer Systems based on Open Standard commonly used in large spacecrafts and PC/104 used …


An Efficient Strategy For Deploying Deception Technology, Noora Abdulla Alhosani Jun 2023

An Efficient Strategy For Deploying Deception Technology, Noora Abdulla Alhosani

Theses

Implementations of deception technology is crucial in discovering attacks by creating a controlled and monitored environment for detecting malicious activity. This technology involves the deployment of decoys, traps, and honeypots that mimic natural systems and network assets to attract and identify attackers. The use of deception technology provides an early warning system for detecting cyber-attacks, allowing organizations to respond quickly and mitigate damage. This article proposed a framework that focuses on maximizing the efficiency of deception technology in detecting sophisticated attacks. The framework employs multi-layered deception techniques at various levels of the network, system, and application to provide comprehensive coverage …


Digital Transformation In Local Governments: A Case Study Of Abu Dhabi Municipality Transport Department, Alia Sahmi Al Ahbabi Jun 2023

Digital Transformation In Local Governments: A Case Study Of Abu Dhabi Municipality Transport Department, Alia Sahmi Al Ahbabi

Theses

The new generation is rapidly adapting to the digital era, where government and private services are being transformed into electronic services, commonly known as Eservices. Cities are leveraging digitalization to streamline their business processes and business services. This digitalization has improved service delivery time and quality for individuals. With digitalization, business processes align with technology, enhancing performance and customer satisfaction. However, there are challenges associated with digitalization, particularly people working in various municipality departments who find it challenging to adapt to digitization. Employees may take time to adjust to the new techniques and technologies, which may hamper the actions of …


Cloud Tracking Winds On Mars Using Emm-Exi Imaging, Shaimaa Ahmed Alblooki Jun 2023

Cloud Tracking Winds On Mars Using Emm-Exi Imaging, Shaimaa Ahmed Alblooki

Theses

The Martian atmospheric wind structure is a major unknown in our understanding of Mars’ climate because it is difficult to measure wind remotely. The Emirates eXploration Imager (EXI) instrument on board the Emirates Mars Mission (EMM) takes visible and ultraviolet images of the whole hemisphere of the planet at a time, and can capture complete weather systems at once, along with their evolution over time. This project uses EXI 320 nm observations to measure winds on Mars using Correlation Imaging Velocimetry (CIV), a cloud tracking method based on software developed for laboratory fluid dynamics experiments, and with significant heritage in …


Fog Harvesting Using Chemically Functionalized Porous Membranes, Afra Saif Alhumaidi Jun 2023

Fog Harvesting Using Chemically Functionalized Porous Membranes, Afra Saif Alhumaidi

Theses

This work explores the use of chemically functionalized porous membranes for fog harvesting. Fog water has emerged as a valuable alternative water source in regions where traditional freshwater resources are scarce. However, conventional fog harvesting techniques often suffer from low collection efficiency and limited scalability. To address these challenges, this research investigates the potential of chemically functionalized porous membranes for enhanced fog water collection. The study focuses on the development and characterization of specialized membranes with surface properties optimized for efficient fog droplet capture.
The current study proposes the use of aluminum mesh for fog collection, as it stands out …


Invariants Of 3-Braid And 4-Braid Links, Mark Essa Sukaiti May 2023

Invariants Of 3-Braid And 4-Braid Links, Mark Essa Sukaiti

Theses

In this study, we established a connection between the Chebyshev polynomial of the first kind and the Jones polynomial of generalized weaving knots of type W(3,n,m).
Through our analysis, we demonstrated that the coefficients of the Jones polynomial of weaving knots are essentially the Whitney numbers of Lucas lattices which allowed us to find an explicit formula for the Alexander polynomial of weaving knots of typeW(3,n).
In addition to confirming Fox’s trapezoidal conjecture, we also discussed the zeroes of the Alexander Polynomial of weaving knots of type W(3,n) as they relate to Hoste’s conjecture. In addition, …


Interactive Emirate Sign Language E-Dictionary Based On Deep Learning Recognition Models, Ahmed Abdelhadi Abdelhadi Apr 2023

Interactive Emirate Sign Language E-Dictionary Based On Deep Learning Recognition Models, Ahmed Abdelhadi Abdelhadi

Theses

According to the ministry of community development database in the United Arab Emirates (UAE) about 3065 people with disabilities are hearing disabled (Emirates News Agency - Ministry of Community Development). Hearing-impaired people find it difficult to communicate with the rest of society. They usually need Sign Language (SL) interpreters but as the number of hearing-impaired individuals grows the number of Sign Language interpreters can almost be non-existent. In addition, specialized schools lack a unified Sign Language (SL) dictionary, which can be linked to the Arabic language being of a diglossia nature, hence many dialects of the language co-exist. Moreover, there …


Valuation Of Asian Options In A High Volatility Market With Jumps, Zeeshan Khalid Apr 2023

Valuation Of Asian Options In A High Volatility Market With Jumps, Zeeshan Khalid

Theses

The evaluation of financial derivatives represents a central part of financial risk management. There are many types of derivatives among other path-dependent options. In this study, we aim at valuing Asian options. They are path dependent and have several benefits. For instance, their values are habitually lower than European options. Also, an Asian option on a commodity drops the risk value close to maturity. Though, the disadvantage is that they are in general difficult to value since the distribution of the payoff is usually unknown. It is agreed in the literature that a stochastic process with a jumps model for …


A Support Theorem For A Wave Equation, Aysha Khaled Alshamsi Apr 2023

A Support Theorem For A Wave Equation, Aysha Khaled Alshamsi

Theses

It is well known that the fundamental solution to the classical wave equation Δ𝑢 (𝑥, 𝑡) − ∂𝑡𝑡𝑢(𝑥,𝑡) = 0 is supported on the light cone {(𝑥, 𝑡) ∈ ℝ𝑛× ℝ : ||𝑥|| = |𝑡|} if and only if the dimension 𝑛 is odd and ≥ 3. Because we are living in a 3-dimensional world we can hear each other clearly; One has a pure propagator without residual waves. In this thesis we consider the wave equation

2||𝑥||Δ𝑘𝑢𝑘(𝑥, 𝑡) − ∂𝑡𝑡𝑢(𝑥,𝑡) = 0, (𝑥, 𝑡) ∈ ℝ𝑛 × ℝ …


Cheating Detection In Online Exams Based On Captured Video Using Deep Learning, Aysha Sultan Alkalbani Apr 2023

Cheating Detection In Online Exams Based On Captured Video Using Deep Learning, Aysha Sultan Alkalbani

Theses

Today, e-learning has become a reality and a global trend imposed and accelerated by the COVID-19 pandemic. However, there are many risks and challenges related to the credibility of online exams which are of widespread concern to educational institutions around the world. Online exam system continues to gain popularity, particularly during the pandemic, due to the rapid expansion of digitalization and globalization. To protect the integrity of the examination and provide objective and fair results, cheating detection and prevention in examination systems is a must. Therefore, the main objective of this thesis is to develop an effective way of detection …


The Reproducing Kernel Method For Solving Integro-Differential And Volterra Integral Equations, Khulood Gamal Qaid Apr 2023

The Reproducing Kernel Method For Solving Integro-Differential And Volterra Integral Equations, Khulood Gamal Qaid

Theses

Integro-differential equations are a class of mathematical equations that involve both derivatives and integrals. They have applications in a wide range of fields, including physics, engineering, finance, and biology such as the spread of diseases, population dynamics, and the behavior of financial markets. The study of these equations requires advanced mathematical techniques, including functional analysis, approximation methods, and numerical analysis. They are a rich area of research with many open questions and challenges.
In this thesis, we will develop and implement the reproducing kernel method to solve a class of integro-differential and Volterra integral equations. We discuss both cases when …


A Comparative Study On Microchip Implants In Humans And Wearable Devices, Ltifa Mohammed Almansoori Apr 2023

A Comparative Study On Microchip Implants In Humans And Wearable Devices, Ltifa Mohammed Almansoori

Theses

After the tragic covid pandemic in 2020, many things changed in the world, from learning physically all the way to e-learning, as the whole world was forced to switch digitally. It is expected that a lot of people will be more willing to invest in new technologies that aid in human development and among them are human microchip implants. The emerging technology of human microchip implants is slowly catching the attention of various countries around the world after the sudden surge of adoption in Europe. With the introduction of Biohax microchip implants in the UAE by Etisalat it is most …


Biohydrogen Production Of A Co-Culture Consisting Of Halophytic Cyanobacterium Phormidium Keutzingianum And Activated Sludge Bacteria Using Different Exogenous Carbon Substrates And Salt Concentrations, Maitha Mohammed Al Nuaimi Apr 2023

Biohydrogen Production Of A Co-Culture Consisting Of Halophytic Cyanobacterium Phormidium Keutzingianum And Activated Sludge Bacteria Using Different Exogenous Carbon Substrates And Salt Concentrations, Maitha Mohammed Al Nuaimi

Theses

Various studies have proved the ability of different types of cyanobacteria and algae to produce hydrogen (H2) by splitting water molecules into H2 and oxygen (O2) using specialized enzymes (hydrogenase and nitrogenase enzymes) through the biophotolysis process. However, the production of O2 acts as the main process inhibitor. Several researchers studied this O2 sensitivity and proposed effective solutions to regulate O2 concentration. By co-culturing algae with aerobic bacteria, the consumption of the resulting oxygen could be attained and thus reducing the sensitivity of the enzyme to the evolved O2. In …


Data-Driven Modeling Of Student Performance In The Time Of Distance Learning, Iman Saad Megdadi Apr 2023

Data-Driven Modeling Of Student Performance In The Time Of Distance Learning, Iman Saad Megdadi

Theses

One of the important aspects that all academic institutions work towards improving is Student Performance. It is obviously the primary indicator of success or failure of institutions. Student performance predictions are vital to instructors and educational decision makers to help, across all levels, tailor learning according to the students’ needs. Therefore, it is essential for Higher Education Institutions to predict student performance in distance learning which has been, and remains, the primary method of learning in some countries due to Corona Virus pandemic. For this reason, this research is going to predetermine a fitting definition of student performance in time …


Correlation Between The Preparation Methods And The Physiochemical Characteristics Of Mgal₂O₄ As A Support For Ni Catalysts In Partial Oxidation Of Methane, Fatima El Alem Mar 2023

Correlation Between The Preparation Methods And The Physiochemical Characteristics Of Mgal₂O₄ As A Support For Ni Catalysts In Partial Oxidation Of Methane, Fatima El Alem

Theses

Due to different technical challenges associated with direct use of methane, the main component of natural gas, its conversion to higher hydrocarbons has been a subject of great industrial importance. All of the known routes for methane conversion are catalytic processes, where the performance is largely dependent on the physicochemical properties of the catalyst. The catalysts that have shown promising performance in methane reforming are based on expensive metals such as Pt, Pd, and Ru. Ni, on the other hand, is a cost-effective metal and has shown promising catalytic activity. These catalysts are usually in the form of metal nanoparticles …


Generating Synthetic Satellite Images Of Mars Dust Storms Based On Radiative Transfer Models, As A Follow-On Application Of Marswrf Dust Cycle Simulations, Fatima Ali Alkaabi Mar 2023

Generating Synthetic Satellite Images Of Mars Dust Storms Based On Radiative Transfer Models, As A Follow-On Application Of Marswrf Dust Cycle Simulations, Fatima Ali Alkaabi

Theses

Dust is a fundamental component of the Martian atmosphere; it plays a vital role in the planet's climate system and atmospheric variability. For these reasons, it is considered one of the essential keys to understanding the Martian atmosphere's behavior. The dust events on Mars range from local/regional dust storms that occur every Martian year to global dust storms that have only been observed, on average, once every 3-4 Martian years. The large regional and global dust storms have strong thermal and dynamic effects on the atmosphere. MarsWRF is a Mars version of the terrestrial numerical weather and climate model WRF …


The Three-Dimensional Visualization Of Mars Dust Storms Based On Deriving Digital Elevation Maps From Satellite Imagery, Meirah Ali Alzeyoudi Mar 2023

The Three-Dimensional Visualization Of Mars Dust Storms Based On Deriving Digital Elevation Maps From Satellite Imagery, Meirah Ali Alzeyoudi

Theses

This work focuses on generating a Three-Dimensional Visualization of Mars's local dust storms utilizing satellite images from publicly available archives. The work aimed to create a Three-Dimensional Visualization of two Local Dust storms, the first local dust storm occurred on May 20, 2020, in the Chryse Planitia Region of Mars, while the second one occurred on 8 June 2021, on the northern side of the Utopia Planitia Region of Mars. The visualization will assist in providing a better understanding of the dynamics of Dust Storms on Mars by indicating and analyzing the main features of dust storms on Mars. Also, …


Mathematical Models For Thalassemia, Hamda Mohammed Al Dhaheri Mar 2023

Mathematical Models For Thalassemia, Hamda Mohammed Al Dhaheri

Theses

Thalassemia is a genetic blood disorder caused by gene mutation or deletion in a blood protein called hemoglobin. Treatment of thalassemia requires a life-long blood transfusion and removal of excessive iron in the blood stream, which usually causes a big pressure on health care systems. Various forms of thalassemia control measures have been used to reduce the prevalence of thalassemia major. This has resulted in a substantial reduction in the prevalence of thalassemia. However, the thalassemia carrier population remains high, which could lead to an increase in the thalassemia major population through carrier-to-carrier marriages. Thus, we developed two mathematical models …


Design And Assessment Of A Leo Gnss Miniconstellation For Positioning, Navigation, And Timing (Pnt), Mariya Abdulkhaleq Mohamad Mar 2023

Design And Assessment Of A Leo Gnss Miniconstellation For Positioning, Navigation, And Timing (Pnt), Mariya Abdulkhaleq Mohamad

Theses

Recently, there has been a resurgent demand in the United Arab Emirates for more accurate positioning, navigation, and timing signals, especially for some targeted applications such as autonomous vehicles and flying taxis. The existing Global Navigation Satellite Systems (GNSS) provide real-time positioning accuracy for up to several meters, while the targeted applications require fast convergence of centimeterlevel positioning accuracy. Recent studies have shown that transmitting GNSS signals from a Low Earth Orbit (LEO) instead of a Medium Earth Orbit (MEO) would enhance positioning accuracy. The main objective of this thesis is to design and simulate an optimum scenario of a …


First-Principles Calculations On The Electronic Structure, Mechanical, Vibrational, And Thermal Properties Of The Ca₃Bin Antiperovskite Alloy, Reem Maher Mohamad Feb 2023

First-Principles Calculations On The Electronic Structure, Mechanical, Vibrational, And Thermal Properties Of The Ca₃Bin Antiperovskite Alloy, Reem Maher Mohamad

Theses

Antiperovskites are the counterparts of perovskites. They have diverse properties that make them physically rich and technologically relevant. In the recent years, the alkaline earth based antiperovskites, especially the ones with small semiconductor bandgap, have captured tremendous attention due to their properties which make them efficient to be used in optoelectronic and thermoelectric applications. In this thesis, we are shading light on the alkaline antiperovskite 𝐶𝑎3𝐵𝑖𝑁 due to its narrow bandgap. Thus, it can be considered as a promising candidate for thermoelectric and optoelectronic applications. Specifically, it is used to harvest waste thermal energy into electricity at low …


Modified Titani Derived From Ti – Oxo Clusters: Synthesis, Structure, And Photocatalytic Activity, Fatmah Rashed Ali Alkindi Nov 2022

Modified Titani Derived From Ti – Oxo Clusters: Synthesis, Structure, And Photocatalytic Activity, Fatmah Rashed Ali Alkindi

Theses

Titanium dioxide (TiO2), an important semiconductor, has been used in various applications ranging from sunblock additives to self-cleaning window coatings, antibacterial agents, photovoltaics, and photocatalysis. Due to its photostability, TiO2 is an extensively used semiconductor photocatalyst in many industries. This thesis represents the synthesis, structure, and photocatalytic activity of TiO2 (Anatase) photocatalyst, which was prepared using hexanuclear titanium-oxo cluster precursor via temperature-controlled calcination. The optical property of the prepared photocatalyst was investigated using UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS), powder X-ray diffraction (PXRD) for phase determination, scanning electron microscopy (SEM) for morphology and structural analysis, Brunauer−Emmett−Teller …


On The Projections Of Commutative C*-Algebras, Alaa Ahmad Hamdan Nov 2022

On The Projections Of Commutative C*-Algebras, Alaa Ahmad Hamdan

Theses

Gelfand and Naimark proved that the Banach algebra of continuous complex-valued functions on a compact space Ω is the only example of commutative unital C*-algebras. We study the C*-algebra C(Ω) and its main elements, such as projections. Also, we discuss the mapping between projections, which preserves orthogonality (orthoisomorphism). A bijective θ between projections induces a bijective Θ between the Boolean algebra of clopen subsets of X. Then, we give main properties of such Θ. For a compact subset X of ℝ, we classify the projections of C(X) by introducing the similar relation on P(C(X)). We introduce an …