Engineering Commons^™

Characterization And Structural Shear Behavior Of Recycled Aggregate Concrete Beams Reinforced With Basalt Fibers And Basalt Bars, Shahrukh Shoaib Ul Haq

Dissertations

Recycling construction waste material offers a sustainable solution to the problem of disposing of concrete construction and demolition waste. The use of basalt fibers (BF) and basalt fiber-reinforced polymer (BFRP) reinforcing bars in concrete structures made of recycled concrete aggregate (RCA) would prolong their service life and reduce the maintenance cost. This research aims to investigate the potential use of BF, RCA, and BFRP reinforcing bars to produce sustainable and steel-free structural concrete. The study consisted of material characterization testing, numerical simulation, and large-scale beam testing.
Material characterization tests were performed on normal-strength concrete (NSC) and high-strength concrete (HSC). The …

Aerodynamic & Aeroacoustic Performance Of Wind Turbine Blades Featuring Enhanced Flow-Control, Md Zishan Akhter

Dissertations

Wind energy, being one of the cleanest and most sustainable sources, has undergone remarkable growth in recent years due to advancements in aerodynamics and increased power output. The research community is actively pursuing the development of cutting-edge solutions to further optimize wind turbine technology, ensuring its maximum efficiency and revolutionizing the landscape of wind power.
This research aims to design and develop flow-control devices for wind turbine blades, employing both active and passive control mechanisms, namely morphing trailing-edge and slot-profile, respectively. The objective is to enhance wind turbine performance across a wide range of wind speeds. The morphing trailing-edge mechanism …

Biological Seawater Desalination Using Green Algae And Cyanobacteria, Abdul Mannan Zafar

Dissertations

Water shortage in many coastal parts of the world is reaching alarming situation, including the United Arab Emirates. Urbanization and rapid population growth are generating critical water demands with an increase in per capita consumption. Seawater is usually treated by membrane processes such as Reverse Osmosis (RO). However, this technology is energy intensive and generates excessive brine as a waste. The solution to this problem can be found in natural remediation techniques that can reduce salt concentration from seawater, such as halophytes. A salt-tolerant species can consume Na⁺ and Cl^- ions and increase cellular growth which is termed …

Approximate Computing Based Processing Of Mea Signals On Fpga, Mohammad Emad Hassan

Dissertations

The Microelectrode Array (MEA) is a collection of parallel electrodes that may measure the extracellular potential of nearby neurons. It is a crucial tool in neuroscience for researching the structure, operation, and behavior of neural networks. Using sophisticated signal processing techniques and architectural templates, the task of processing and evaluating the data streams obtained from MEAs is a computationally demanding one that needs time and parallel processing.

This thesis proposes enhancing the capability of MEA signal processing systems by using approximate computing-based algorithms. These algorithms can be implemented in systems that process parallel MEA channels using the Field Programmable Gate …

Integrating Kano Model With Data Mining Techniques To Enhance Customer Satisfaction, Khaled Abdulla Ali Al Rabaiei

Dissertations

The business world is becoming more competitive from time to time; therefore, businesses are forced to improve their strategies in every single aspect. So, determining the elements that contribute to the clients' contentment is one of the critical needs of businesses to develop successful products in the market. The Kano model is one of the models that help determine which features must be included in a product or service to improve customer satisfaction. The model focuses on highlighting the most relevant attributes of a product or service along with customers’ estimation of how these attributes can be used to predict …

A Comprehensive Evaluation Of Satellite-Based Precipitation Products And Their Performance In Arid And Temperate Climates, Mohammed Tarig Mahmoud

Dissertations

Accurate and continuous precipitation monitoring is critical to enable effective water resources management; the challenge arises from the spatial and temporal variability of precipitation. The recently launched Global Precipitation Measurement (GPM) satellite has the capability to detect and measure all types of precipitation using advanced instruments. Being at its early stages of development, the products of the GPM IMERG (early, late, and final-run-products) need to be validated using multiple spatial and temporal assessment techniques. Several studies have emerged over the past few years evaluating GPM IMERG results over areas of limited size. These areas were set by hydrologic interest (e.g., …

Membrane Bioreactor For Enhanced Enzymatic Hydrolysis Of Cellulose, Saleha Abdullah Al-Mardeai

Dissertations

With the rising environmental concerns related to fossil fuels utilization and the depletion of these resources, interest in bioethanol from lignocellulosic waste as an alternative, sustainable energy source has been increasing. Date palm waste is considered a good feedstock for bioethanol production, especially in countries of large date palm plantations, such as the United Arab Emirates.

In the lignocellulose to bioethanol process, the enzymatic hydrolysis of celluloses to produce simple sugars that can be converted to bioethanol by fermentation is the most challenging step, and enhancing it is essential for efficient and feasible operation. Enzyme inhibition by the products is …

Koh-Based Modified Solvay Process: Optimization And Kinetics Studies, Aya Abdel-Hamid Mourad

Dissertations

While desalination of seawater is important for meeting the water demand, the technology produces large volumes of reject brine and CO₂, causing environmental pollution. Solvay process (based on ammonia, NH₃) and modified Solvay process (based on calcium oxide, CaO) try to manage these wastes. However, more attention is needed to overcome different limitations of these processes such as, alkaline solubility, operating temperature, maintaining high pH value, and low sodium (Na⁺) removal efficiency, which does not exceed 35%. The aim of this work is to introduce an alternative alkaline, namely potassium hydroxide (KOH) and investigate …

Behavior Of Steel Fiber Reinforced Concrete Made With Recycled Concrete Aggregates: Material Characterization And Deep Beam Shear Response, Nancy Kachouh

Dissertations

This research aims to examine the performance of concrete made with recycled concrete aggregates (RCAs) and steel fibers. It comprises material characterization tests, large-scale reinforced concrete (RC) deep beam tests, and numerical modeling. Material characterization test parameters included the RCA replacement percentage (30, 70, and 100%) and the steel fiber volume fraction (vf = 1, 2, and 3%). Fourteen large-scale deep beam numerical models with and without web openings made with 100% RCAs and steel fibers were developed and validated through a comparative analysis with test results. A numerical parametric study was conducted to investigate the effect of varying …

Utilization Of Triply Periodic Minimal Surface (Tpms) Based Architectures Impregnated With Phase Change Material For Heat Transfer Applications, Zahid Ahmed Qureshi

Dissertations

This dissertation is concerned with the utilization of mathematically architected Triply Periodic Minimal Surface (TPMS) based lattices for Latent Heat Thermal Energy Storage (LHTES) systems. With the advent of Additive Manufacturing (AM), TPMS structures can be readily manufactured. The objective of this dissertation was to investigate the heat transfer performance of TPMS structures vis-à-vis conventional metal foams represented by Kelvin cells while both were impregnated with a Phase Change Material (PCM). Numerical simulations were performed under various boundary conditions to assess the performance. It was found that TPMS structures outperformed conventional metal foam. Moreover, the effects of boundary conditions (isothermal …

Multi Stage Modified Solvay Process For Co2 Capture And Reject Brine Desalination, Ameera Fares Mohammad

Dissertations

Brine management is an environmental concern, as many desalination plants need to find suitable approaches for the treatment or disposal of the large amounts of concentrated brine that are produced. Many conventional methods are used such as disposal through deep well injection, but these methods still suffer from many drawbacks. An alternative approach is to further process the brine by extracting the salts through reactions with carbon dioxide. The chemical reactions of reject brine with high alkalinity products and carbon dioxide are postulated to constitute a new, effective, economic and environmentally friendly approach. On the other hand, a major challenge …

Simple Procedure For Calculating Parameters Of Permanent Magnet Linear Generator And Methods For Maximizing Power Absorption Using Less Dependent Mathematical Model / Low Computationally Cost Controllers In Wave Energy Converters, Bisni Fahad Mon

Dissertations

The study comprises of designing permanent magnet linear generator (PMLG) for wave energy converters (WECs) and method for maximizing power absorption using less dependent mathematical model or low computationally cost controllers. There are three proposed controller methods: the damping control using maximum power point tracking (MPPT), the reactive control using MPPT, and finite control set model predictive control (FCSMPC).

The first part of the thesis is started with the design and testing of a laboratory scale test-rig for wave energy converters (WECs). The main element of the test-rig is a double-sided permanent magnet linear generator (PMLG). In this study, detailed …

Development Of A Decision Support System For Sustainable Water Planning In Abu Dhabi, Uae, Mohamed Ibrahim Kizhisseri

Dissertations

One of the main challenges for water managers is to foresee the future accurately; then, design appropriate policies and infrastructure plans accordingly. The use of decision support systems in the field of water resource management and planning is now widely implemented, but its use in sustainable water planning of a nation or state in arid and semi-arid areas, such as Middle East countries, remains limited. The main objective of this dissertation is to present a graphical software tool that can assist water planners and decision-makers in long-term water management and planning. Sustainable planning for Abu Dhabi’s future water supply is …

Experimental Investigation And Prediction Of Long-Term Effect Of Sustained Load And Harsh Environment On Fiber-Reinforced Polymer Composites, Amir Hussain Idrisi

Dissertations

In this dissertation the durability of thermoset composites was investigated under sustained load. Two thermoset composites, E-glass/epoxy and E-glass/polyurethane were immersed in seawater under sustained load (10%, 15%, 20%, 25% of failure load) and varying temperature (23°C to 95°C) for the period of 15 months. Mechanical, physical and thermal properties were experimentally investigated. The effects of temperature, moisture, and immersion time on the deterioration of the composite material were studied for both composites. It was observed that the weight of the samples increased with the immersion time and temperature for both the composites. The highest increase in weight of the …

Development And Characterization Of Sustainable Novel Aluminum Metal Matrix Composites, John Victor Christy

Dissertations

Low crude oil prices have impacted the economy of the Gulf Cooperation Council (GCC) member countries especially the United Arab Emirates (UAE). Hence it is vital to accelerate the diversification of the economy. Among the many potential diversification avenues, manufacturing is a promising area that could add to the GDP. This work brings out a sustainable and cost-effective method for manufacturing AMCs and expanding their applications.

This work deals with the processing and characterization of recycled AMCs manufactured using a novel approach. With the emphasis on sustainable manufacturing, this work aims to use Scrap Aluminum Alloy Wheels (SAAW) of cars …

Wireless Antenna Multiplexing Using Tunable Antenna For Space Applications, Saifudeen Ahammed Kabeer

Dissertations

Recent development in communication technologies shifts the communication paradigm from point to point to multi-user wireless systems. These developments eased the use of mobile telephone, satellite services, 5G cellular, smart application, and the

Internet of Things. The proliferation of mobile devices has necessitated an elaborate mechanism to serve multiple users over a shared communication medium, and a multiplexing approach is introduced to serve this purpose. Multiplexing refers to a method that aims at combining multiple signals into one signal such that each user would be able to extract its desired data upon receiving the multiplexed signal. This spectrum sharing allows …

Design Of Graphene-Based Sensors For Nucleic Acids Detection And Analysis, Asma’ Wasfi Fayez Mustafa

Dissertations

DNA (Deoxyribonucleic Acid) is the blueprint of life as it encodes all genetic information. In genetic disorder such as gene fusion, Copy Number Variation (CNV), and single nucleotide polymorphism, Nucleic acids such as DNA bases detection and analysis is used as the gold standard for successful diagnosis. Researchers have been conducting rigorous studies to achieve genome sequences at low cost while maintaining high accuracy and high throughput. A quick, accurate, and low-cost DNA detection approach would revolutionize medicine. Genome sequence helps to enhance people’s perception of inheritance, disease, and individuality. This research aims to improve DNA bases detection accuracy, and …

Thermal Evaluation Of Advanced Leading Edge For Rotating Gas Turbine Blade: Numerical And Experimental Investigations, Amin Safi

Dissertations

Gas turbine engines play a vital role in our life. Our power demand is significantly and continuously growing. One approach to improve thermal efficiency in gas turbine engines requires a higher turbine inlet gas temperature. Advanced gas turbine engines operate at high temperatures, around 2000 K. Since operating at high temperatures may compromise the blade structure integrity, different cooling systems are used in a turbine blades. One of the most efficient cooling techniques is impingement cooling, mostly used in the leading edge. The leading edge experiences the highest temperature in the blade exposed to the hottest gas.

Researchers studied different …

Conversion Of Lignocellulose Biomass From Date Palm Waste To High Value Chemicals, Emmanuel Galiwango

Dissertations

Lignocellulose biomass has gained growing popularity because of its low cost of production compared to food crops, it solves problems of food and energy security, can grow in various climates and land, and it is CO₂ neutral. Date palm trees produce large amounts of fibrous wastes that are good sources of lignocellulose. There are over 40 million date palm trees in UAE and most of their lignocellulosic wastes (i.e., leaves, surface fibers, bunches, etc.) are currently used for low value applications such as compost or electric generation. However, the lignocellulosic components of this waste stream have the potential to …

Investigating The Contribution Of Historic Site Interpretation Centers To Meaning Making: The Case Of Bahrain, May Jalal Al Saffar

Dissertations

This dissertation investigates the role and contribution of the Historic Site Interpretation Centers in the process of meaning-making from the historic site to the visitors, as well as their visiting experience and attendance at the same settings. The Historic Site Interpretation Centers exhibit a unique museum typology dedicated to sites of historical significance, offering a dual mode of interpretation, labeled as ‘in situ’ and ‘in context’. The objective was to evaluate the physical attributes and applied display strategies in conveying meaning from historic sites to visitors and, to explore the resulting stakeholders’ (i.e. service providers and visitors) perception and emotional …

Activated Carbon Nanofibers From Renewable (Lignin) And Waste Resources (Recycled Pet) And Their Adsorption Capacity Of Refractory Sulfur Compounds From Fossil Fuels, Efstratios Svinterikos

Dissertations

The development of advanced engineering materials such as carbon nanofibers from low-cost, renewable and/or waste resources is a key aspect of sustainability. In addition, escalating concerns related to the presence of noxious sulfur compounds in commercial fuels are driving the need to develop more efficient desulfurization technologies. In this PhD dissertation research, activated carbon nanofibers were produced from a blend of lignin with recycled poly(ethylene terephthalate) (r-PET) and they were successfully tested for the adsorption of refractory sulfur compounds from a model diesel fuel. Starting from different lignin/r-PET mass ratios, precursor nanofibers of different morphologies were initially prepared using the …

Electrical Characterization And Detection Of Blood Cells And Stones In Urine, Nida Nasir

Dissertations

Urine contains an immense amount of information related to its physical, chemical, and biological components; hence, it is a promising tool in detecting various diseases. Available methods for detecting hematuria (blood in the urine) are not accurate. Results are influenced by many factors, such as, health and vitals of the patients, settings of the equipment and laboratories, which leads to false positive or false negative outputs. This necessitates the development of new, accurate, and easy-access methods that save time and effort. This study demonstrates a label-free and accurate method for detecting the presence of red and white blood cells (RBCs …

Enhanced Label Free Normal And Cancer Cells Classification Using Combined Parametric Modeling And Optical Techniques, Ayshathul Fouzia Abdul Gani

Dissertations

The development of label-free methods for cell classifications has been driven by the importance of early detection and identification of cancer disease. The future point-of-care (POC) treatment methods require rapid and real-time cancer screening techniques. As the labelled methods of cell classification are time-consuming processes and require a large amount of sample preparation along with skilled persons, they do not appear to be suitable for POC treatment methods. This necessitates the importance of such development. The label-free methods incorporate the biophysical properties of cells instead of biomarkers. The optical properties of cells have been frequently utilized for cell classification. This …

Modelling And Fault Diagnosis Approach For Proton Exchange Membrane Fuel Cell Systems Incorporating Ambient Conditions, Saad Saleem Khan

Dissertations

Proton exchange membrane fuel cell (PEMFC), as a source of electrical power, provides numerous benefits such as zero carbon emission and high reliability as compared to wind and solar energy. PEMFC operates at very low temperature, high power density, and has very high durability as compared to other fuel cells. Being a non-linear power source with high sensitivity to ambient conditions variation, the prediction of PEMFC voltage and temperature is a complicated issue. The most common PEMFC models are classified as mechanistic models, semi-empirical models, and purely empirical methods. The mechanistic models are complex and require differential equations to predict …

Development Of Piezoelectric Sensors And Methodology For Noninvasive Simultaneous Detection Of Multiple Vital Signs, Areen Abdallah Romi Allataifeh

Dissertations

The activity of piezoelectric material linked the applied electric field with the strain generated that can be translated into geometrical variations. Flexible steel substrate exhibits fascinating mechanical properties which enable their integration into the emerging field of flexible microelectronics. This work presents an extended technique based on capacitance-voltage dependency to extract the geometrical variations in thin-film piezoelectric materials deposited on a flexible steel. A 50 μm flexible steel sheet has been sandwiched by two PZT film layers, each of 2.4 μm in thickness deposited by sputtering. An aluminum layer of 370 nm has been deposited above each PZT layer to …

Modeling And Experimental Study Of Carbon Dioxide Absorption/Stripping In Gas Liquid Membrane Contactor, Nihmiya Abdul Rahim

Dissertations

Natural gas consists primarily of methane (CH4) but it also contains considerable amounts of contaminating compounds mainly carbon dioxide (CO2). The presence of CO2 reduces the heating value of the gas and due to its acidic character causes several operational problems. Hence the removal of CO2 from natural gas is crucially important. The focus of this research work is to investigate the potential for the energy efficient and effective separation of CO2/CH4 gas mixture via lean solvent and regenerating of the rich solvent through absorption/stripping mechanism taking place in a hollow fiber gas liquid membrane contactor process (GLMC) which combines …

Control Strategies For Improving The Performance Of Heaving Wave Energy Converters, Mohammed Abdi Jama.

Dissertations

The main objective of this study is to develop control strategies to enhance the performance of single-body heaving wave energy converters (WECs). Maximizing the energy captured from sea waves while respecting the physical and thermal limitations of the WEC is of a paramount importance for any control strategy to be effective. In addition, it is desirable for the controller to be less vulnerable to model uncertainties and external disturbances. A complete wave-to-wire dynamic model has been derived for the heaving WEC. This includes models that describe the system hydrodynamic forces using the linear wave theory and models that describe the …

Pbs Quantum Dot-Based Hetrojunction Solar Cells, Sawsan Khader Dagher

Dissertations

This study investigates the influence of nanoparticles (NPs) size on their optical properties, and the effect of combination of lead sulfide (PbS) quantum dots (QDs), with n-type and p-type NPs, on the photogenerated charge carriers transport across the heterojunction solar cell structure. PbS QDs, of a range of sizes, were synthesized using a co-precipitation process. In this study, p-type NPs, which are poly [3,4-ethylenedioxythiophene] –poly [styrenesulfonate] (PEDOT: PSS), copper oxide (CuO) and graphene oxide (GO); and n-type NPs which are zinc oxide (ZnO), titanium dioxide (TiO2), cadmium sulfide (CdS) and bismuth sulfide (Bi2S3), were synthesized and characterized by SEM and …

Hydrodynamic Evaluation Of Climate Change And The Effects Of Coastal Effluent On The Long-Term Circulation Ofthe Arabian Gulf And Its Impact On Desalination, Abubaker Awad Elhakeem

Dissertations

The prime objectives of this dissertation are to develop, validate, and use a state of the art 30 Hydrodynamic Model (HD) to evaluate the long-term salinity and seawater temperature variations in the Gulf subject to climate change and coastal effluent; and to develop a Quantification tool that can assess the impact of projected ambient conditions upon the cost of desalination. Both objectives were realized.

Evaluating the long-term variability of seawater salinity and temperature due to climate change and coastal effluent is a growing concern. It may represent an economic and operational limiting factor in the desalination process given the clear …

Resource Allocation For Wireless Relay Networks, Hanan Hassan Al-Tous

Dissertations

In this thesis, we propose several resource allocation strategies for relay networks in the context of joint power and bandwidth allocation and relay selection, and joint power allocation and subchannel assignment for orthogonal frequency division multiplexing (OFDM) and orthogonal frequency division multiple access (OFDMA) systems. Sharing the two best ordered relays with equal power between the two users over Rayleigh flat fading channels is proposed to establish full diversity order for both users. Closed form expressions for the outage probability, and bit error probability (BEP) performance measures for both amplify and forward (AF) and decode and forward (DF) cooperative communication …