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2019

United Arab Emirates University

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Full-Text Articles in Engineering

Thermoresponsive Switchable Solvents For Enhanced, Simultaneous Microalgae Oil Extraction Reaction For Biodiesel Production, Mukhtar Ahmed Ismail Dec 2019

Thermoresponsive Switchable Solvents For Enhanced, Simultaneous Microalgae Oil Extraction Reaction For Biodiesel Production, Mukhtar Ahmed Ismail

Mechanical Engineering Theses

In this study, a thermo-responsive switchable solvent (TSS), with a tunable hydrophobicity by simply changing the temperature (between 25 to 45oC) was used for simultaneous lipids extraction from wet microalgae and biodiesel production. By manipulating the hydrophobicity of the solvent, the cell wall disruption, lipid extraction and transesterification, and product separation steps were all carried out in a single pot, while eliminating the need for the energy intensive and time-consuming drying step. To overcome the problems currently encountered by using conventional alkaline catalysts in the transesterification of lipids, immobilized enzyme has been used. The proposed TSS consisted of an ionic …


Effect Of Fe₃O₄ Nanoparticles On Performance Of Shape Memory Polymers Foam Using Solid State Foaming Process, Tamem Salah Dec 2019

Effect Of Fe₃O₄ Nanoparticles On Performance Of Shape Memory Polymers Foam Using Solid State Foaming Process, Tamem Salah

Mechanical Engineering Theses

The scope of this research is the emerging class of smart materials namely stimulus-responsive shape memory polymers (SMP) that can be actuated on demand to recover their original shape, after being quasi-plastically distorted. SMP are ideal for an integrated intelligent system, in which the structure is heated to a certain temperature to generate reactive motion as pre-programmed. This research aims to employ a new emerging method for generating foam structure; called solid-state foaming. The generated foamed structures are advantageous over fully dense SMP in terms of the low density, high compressibility and high deformations when they recover their permanent shape. …


Multi-Objective Optimal Capacity And Placement Of Distributed Generators In The Power System Networks Using Atom Search Optimization Method, Ashwaq Faisal Alkhatib Dec 2019

Multi-Objective Optimal Capacity And Placement Of Distributed Generators In The Power System Networks Using Atom Search Optimization Method, Ashwaq Faisal Alkhatib

Theses

Nowadays, renewable energy sources become a significant source of energy in the new millennium. The continuous penetration of dispersed resources of the reactive power into power systems is predicted to introduce new challenges. Power loss mitigation and voltage profile development are the major investigation challenges

that recently attracted the attention of researchers in the field of power systems. Distributed generation (DG) is widely preferred because it is a highly effective solution that strengthens the performance of power system networks. This multiobjective function study aims to minimise power losses in the feeders, sustain voltage levels and reduce the application cost of …


Graphene/Polypropylene Nanocomposites, Carmen Karam Abuoudah Dec 2019

Graphene/Polypropylene Nanocomposites, Carmen Karam Abuoudah

Theses

Graphene has been regarded as a multifunctional nanofiller for manufacturing polymer nanocomposites. A small amount of graphene nanosheets is expected to significantly improve the properties of base polymers. The property enhancement, however, is a function of the degree of exfoliation and dispersion of graphene as well as its compatibility with the polymer. The non-polar nature of polyolefins such as polyethylene (PE) and polypropylene (PP) restricts the homogeneous dispersion of graphene, leading to significant agglomeration of the nanosheets and thus, limiting the expected property improvements in polyolefins. Currently, more efforts are focused on finding strategies to improve graphene dispersion in polyolefins. …


Modelling And Fault Diagnosis Approach For Proton Exchange Membrane Fuel Cell Systems Incorporating Ambient Conditions, Saad Saleem Khan Dec 2019

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 …


Synchronous Machine Emulation Of Vsc For Interconnection Of Renewable Energy Sources Through Hvdc Transmission, Mohamed Asker Kanakkayil Nov 2019

Synchronous Machine Emulation Of Vsc For Interconnection Of Renewable Energy Sources Through Hvdc Transmission, Mohamed Asker Kanakkayil

Electrical Engineering Theses

The majority of the energy demand over the past years has been fulfilled by centralized generating stations. However, with a continuously increasing energy demand, the integration of decentralized renewable energy sources (RES) into the power system network becomes inevitable even though these sources affect the stability of the grid due to their intermittency and use of various power converters. The transmission of power over long distances from RES is usually accomplished either by AC or DC transmission. High voltage DC transmission (HVDC) is preferred over high voltage AC transmission (HVAC) due to numerous and complex reasons, such as its lower …


Active Filter Modelling To Mitigate Harmonics Generated By Electric Vehicle Chargers, Fasalu Rahman Puthiyottil Nov 2019

Active Filter Modelling To Mitigate Harmonics Generated By Electric Vehicle Chargers, Fasalu Rahman Puthiyottil

Electrical Engineering Theses

The Automotive industry is going through a rapid transformation to adopt electrified technology. A major share of the electrified vehicles is going to be in the Battery electric vehicles (BEVs) and plug in hybrids segments that need to connect to the grid to recharge the batteries. For customer convenience, the time required for fully charging the battery need to be brought down significantly. EV charging stations are getting installed that could bring down the charging time to less than 30 minutes. However this pose a unique issue to the power quality of the utility grid. During charging, the EV charging …


Strengthening Of Concrete Deep Beams With Extreme Discontinuities Using Near-Surface Mounted Composites, Moustafa Seifeddin Mansour Nov 2019

Strengthening Of Concrete Deep Beams With Extreme Discontinuities Using Near-Surface Mounted Composites, Moustafa Seifeddin Mansour

Civil and Environmental Theses

Installation of a web opening that fully interrupts the natural load path in concrete deep beams produces regions of extreme discontinuities and reduces the shear strength. This research examined the effectiveness of using near-surface-mounted carbon fiber-reinforced polymer (NSM-CFRP) reinforcement to restore the shear strength of deep beams with extreme discontinuities. The strut-and-tie model (STM) procedures were utilized to develop three different strengthening solutions around the discontinuity regions. A total of eight deep beam specimens (150 x 500 x2700 mm) with a shear span-to-depth ratio of a/h = 0.8 were constructed and tested. One beam was solid. Seven beams had a …


The Assessment Of Walkability As A Social Aspect Of Sustainability: The Case Of Dubai Neighborhoods, Uae, Rania Elsaed Elesawi Nov 2019

The Assessment Of Walkability As A Social Aspect Of Sustainability: The Case Of Dubai Neighborhoods, Uae, Rania Elsaed Elesawi

Theses

In an attempt to reduce car dependency, the process of planning, mainly on a neighborhood level, has recently been directed to focus on the accommodation of walkability as a significant factor of planning development. This approach contributes not only to improving urban patterns but also majorly in addressing issues of sustainability. The social aspect of sustainability has not received much attention and is considered the least described pillar. The positive association between aspects of human behavior and built environment, particularly walkability, suggests that measuring social aspects of sustainability may be conceivable especially in the context of community development. Sustainable neighborhoods …


Home Energy Management System For Demand Response Purposes, Isra Adam Hussein Haroun Nov 2019

Home Energy Management System For Demand Response Purposes, Isra Adam Hussein Haroun

Theses

The growing demand for electricity has led to increasing efforts to generate and satisfy the rising demand. This led to suppliers attempting to reduce consumption with the help of the users. Requests to shift unnecessary loads off the peak hours, using other sources of generators to supply the grid while offering incentives to the users have made a significant effect. Furthermore, automated solutions were implemented with the help of Home Energy Management Systems (HEMS) where the user can remotely manage household loads to reduce consumption or cost. Demand Response (DR) is the process of reducing power consumption in a response …


Investigating Nano-Coated Surfaces In Improvement Wear Resistance Of Tillage Tools, Saeed Mehrang Marani, Gholamhossein Shahgholi, Saeed Kanoon Marani Oct 2019

Investigating Nano-Coated Surfaces In Improvement Wear Resistance Of Tillage Tools, Saeed Mehrang Marani, Gholamhossein Shahgholi, Saeed Kanoon Marani

Emirates Journal for Engineering Research

The blade in the tillage operation has the most interaction with soil particles. It causes the wear and tear of this piece and reduces its expected life span. Tillage tool wear is of great importance to farmers in terms of economic aspects, reduced quality tillage operations, and increased power consumption. The aim of this study is to investigate wearing of five materials including st37 steel (SST37) plate, galvanized steel (GAS), and fiberglass (GFRP), and two coatings (i.e., titanium nano-nitride (nano-TiN) and tantalum carbide (nano-TaC)) by sputtering in the plasma medium of the layer based on conventional steel. These pieces were …


Vibration Evaluation Of The Driver’S Seat Of Mf 285 Tractor In Conducting The Tillage Operations, Gholamhossein Shahgholi, Sedagat Fazeli, Saleh Harami Mousavi Oct 2019

Vibration Evaluation Of The Driver’S Seat Of Mf 285 Tractor In Conducting The Tillage Operations, Gholamhossein Shahgholi, Sedagat Fazeli, Saleh Harami Mousavi

Emirates Journal for Engineering Research

The purpose of this study was to investigate the effect of the tractor speed on the tractors’ seat vibration and to assess the level of comfort of the driver during the agricultural operation using moldboard and disc plows. Experiments were conducted on sandy loamy soil in a factorial experiment based on randomized complete block design with three replications. The effect of the type of tillage implement using the moldboard and disc plows, the velocity of advance in four levels of 4.5, 6 and 8.8 km/h and vibration was measured and evaluated at three directions of longitudinal (x), lateral (y) and …


Design, Development And Implementation Of An Electrical Controller For A Solar-Electrical Collector, Sahar Mahboob, Razieh Pourdarbani, Bahman Behfar, Hossein Behfar Aug 2019

Design, Development And Implementation Of An Electrical Controller For A Solar-Electrical Collector, Sahar Mahboob, Razieh Pourdarbani, Bahman Behfar, Hossein Behfar

Emirates Journal for Engineering Research

Todays, maintaining atmospheric health is one of the most important prerequisites for sustainable global economic development, and the international community has no choice but to switch to renewable energies, including solar energy. The goal of the study was to provide a temperature of 60 ° C for drying summer fruits such as apricots therefore we investigated the effect of temperature control systems on the solar-electrical collector performance. Three LM35 temperature sensors were placed at 3 points of the collector (before the air inlet to the collector, after the air outlet from the collector and after heating elements) that were linked …


Quality Evaluation Of The Dewatering Subsurface Water In Urban Areas For Irrigation Purposes, Kuwait, Fawzia Al-Ruwaih, Mohamed El Anbaawy, Ahmad Abdelhalim, Abdulaziz Al-Shammari Jul 2019

Quality Evaluation Of The Dewatering Subsurface Water In Urban Areas For Irrigation Purposes, Kuwait, Fawzia Al-Ruwaih, Mohamed El Anbaawy, Ahmad Abdelhalim, Abdulaziz Al-Shammari

Emirates Journal for Engineering Research

The objective of this study is to assess the quality of the dewatered groundwater and identify its suitability for irrigation purposes in an urban study area by analyzing its chemical composition. The water quality for irrigation has been assessed by the determination of the residual sodium bicarbonate (RSBC), potential salinity (P.S), sodium adsorption ration, (SAR), Mg ratio (MgR), sodium percentage (%Na+), Kelly’s ratio (KR), permeability index (P.I), electrical conductivity, EC, total dissolved solids TDS, total hardness (TH), and pH. The WATEQ4F computer program has been used to compute the saturation indices of some minerals with respect to water …


Daylight Illuminance In Classrooms Adjacent To Covered And Uncovered Courtyards Under The Clear Sky Of Najran City, Saudi Arabia, Abdultawab M. Qahtan Jul 2019

Daylight Illuminance In Classrooms Adjacent To Covered And Uncovered Courtyards Under The Clear Sky Of Najran City, Saudi Arabia, Abdultawab M. Qahtan

Emirates Journal for Engineering Research

Daylight penetrating the classrooms makes students efficient, improves overall health and increases energy efficiency. In the hot regions, the concept of courtyards in buildings is deeply linked to the architecture as a sustainable solution to daylight indoors without negatively affecting the building cooling loads in the summer. Najran University has existing courtyards in college buildings. Recently, the university covered the courtyards using PVC canvas. This study aims to investigate and compare the daylight illuminance in classrooms adjacent to covered and uncovered courtyards. A case study of four classrooms in the College of Engineering was investigated under the clear sky of …


Thermal Characterization Of Graphene/Polyethylene Nanocomposites, Ahmed Z. A. Abuibaid Jun 2019

Thermal Characterization Of Graphene/Polyethylene Nanocomposites, Ahmed Z. A. Abuibaid

Chemical and Petroleum Engineering Theses

Practically, almost all polymers are solidified from the melts for product-forming purposes. Therefore, the evolution of solid structure (crystallization behavior) from their molten form has prime importance in manufacturing high performance materials. Polyethylene (PE) is one of the most commonly used semi crystalline polymers all over the world. In this thesis, nanocomposites of PE with thermal reduced graphene (TRG) (PE/TRG) were prepared via solvent blending and the crystallization of PE has been investigated using a differential scanning calorimeter (DSC). The nanocomposites were crystallized from the melts under both isothermal and dynamic conditions, and evolution of crystal formation is studied using …


Determination Of Cleaning Frequency And Power Enhancement Of Photovoltaic Panels Using Novel Cleaning Approach, Ali Hasan Shah Jun 2019

Determination Of Cleaning Frequency And Power Enhancement Of Photovoltaic Panels Using Novel Cleaning Approach, Ali Hasan Shah

Electrical Engineering Theses

Dust accumulation on the photovoltaic (PV) surface decreases the solar radiation penetration to the PV cells and eventually the power production from the PV system. In order to prevent the dust-based power losses, the PV systems are required to be cleaned frequently depending upon different geographical locations, PV integration schemes, and the scale of the PV power plant. In large-scale power plants, the PVs are periodically cleaned traditionally by water sprinkling that requires sophisticated equipment mobile equipment that at the best involves robotics and hence calls for substantial capital investment as well as water consumption. Since most of the largescale …


Functionalization Of 2d-Zno For Selective Gas Sensing: First-Principles Analysis, Alaa F. M. Shaheen Jun 2019

Functionalization Of 2d-Zno For Selective Gas Sensing: First-Principles Analysis, Alaa F. M. Shaheen

Mechanical Engineering Theses

The scope of this MSc thesis is to theoretically search for suitable materials and relevant factors (e.g., dopants and catalysts) to induce gas sensing (GS) selectivity towards harmful gases such as H2, H2S, and CO2, under ambient conditions. We chose as material 2D-ZnO Honeycomb in the form of nanoribbon (ZnO-NR), which is very promising in the gas sensing applications. We employed a state-of-the-art computational method, based on a combination of the density-functional theory (DFT) and the Non-Equilibrium Green’s Functions (NEGF) formalism, which both are incorporated in Atomistic Toolkit (ATK) package. This package is famous …


Distributed Compressive Sensing Algorithm For Photoacoustic Tomography, Maha Abdulwahab Hassan Shehada May 2019

Distributed Compressive Sensing Algorithm For Photoacoustic Tomography, Maha Abdulwahab Hassan Shehada

Electrical Engineering Theses

Biomedical imaging techniques are playing an essential role in diagnosing different kinds of diseases, which always motivates the search for improving their sensitivity and accuracy. Photoacoustic Tomography (PAT) is one of the most powerful techniques. PAT has many advantages as it is less expensive and faster than Magnetic Resonance Imaging (MRI). It combines the advantages of optical imaging and ultrasound imaging as it provides high contrast, high penetration, and high-resolution images for biological tissues. Also, it uses non-ionizing radiation which is very safe for human health. The main challenge in PAT is that human tissues can be exposed only to …


Optimization Of Low Salinity Water Flooding In Low Permeability Oil Reservoir Yang Li, Yang Li May 2019

Optimization Of Low Salinity Water Flooding In Low Permeability Oil Reservoir Yang Li, Yang Li

Chemical and Petroleum Engineering Theses

In recent decades, the demand of energy is growing sharply. Oil plays a very important role among all of the energy resources. Low permeability oil reservoirs classified as non conventional oil reservoirs and needs special techniques for oil recovery. The primary aim of this study is to select a proper technique for oil recovery of low permeability carbonate oil reservoir. Different carbonated and non-carbonated brines were employed in this project. Formation brine (17500 ppm), carbonate formation brine, sea water, low salinity water, carbonated sea water (50000 ppm), and carbonated low salinity brine (5000 ppm) were used in this work. Core …


Building A Simple Smart Factory, Iman Abdulwaheed May 2019

Building A Simple Smart Factory, Iman Abdulwaheed

Mechanical Engineering Theses

This thesis describes (a) the search and findings of smart factories and their enabling technologies (b) the methodology to build or retrofit a smart factory and (c) the building and operation of a simple smart factory using the methodology. A factory is an industrial site with large buildings and collection of machines, which are operated by persons to manufacture goods and services. These factories are made smart by incorporating sensing, processing, and autonomous responding capabilities.

Developments in four main areas (a) sensor capabilities (b) communication capabilities (c) storing and processing huge amount of data and (d) better utilization of technology …


Mechanical Characterization And Fracture Behavior Of Magnesium Zk60a Alloy (Uns M16600), Mohamed Kamal I. H. Temraz May 2019

Mechanical Characterization And Fracture Behavior Of Magnesium Zk60a Alloy (Uns M16600), Mohamed Kamal I. H. Temraz

Theses

This research work focuses on studying the mechanical and fracture behavior of one of magnesium ZK60A (UNS M16600) extrusion. The material has many industrial applications and its characteristic should be measured for proper component or system design. Several tests were conducted following the standard procedures to determine the mechanical characteristics of the material. In addition, the fracture toughness of the material has been measured using the fracture toughness-thickness curve. A stress intensity factor K was used as a fracture parameter to determine the plane strain fracture toughness KIC of ZK60A magnesium alloy using a single edge notch bend (SENB) specimen …


Feasibility Study Of Direct Application Of Two Deep And Dry Geothermal Wells For Heating The Buildings Of Moeil Village, Razieh Pourdarbani, Massomeh Alibaba, Mohsen Taghaddosi Apr 2019

Feasibility Study Of Direct Application Of Two Deep And Dry Geothermal Wells For Heating The Buildings Of Moeil Village, Razieh Pourdarbani, Massomeh Alibaba, Mohsen Taghaddosi

Emirates Journal for Engineering Research

No abstract provided.


An Evaluation Of Two Controller Implementations For An Inverted Pendulum On Cart System, Shaima Abdul Wahab Ali Al Habsi Apr 2019

An Evaluation Of Two Controller Implementations For An Inverted Pendulum On Cart System, Shaima Abdul Wahab Ali Al Habsi

Electrical Engineering Theses

Various embedded systems are available for control system design and implementation in either lab experiments of postgraduate and undergraduate courses in the area of dynamics and control, or in experimental academic research. The focus of this Master thesis project is set to study, compare and evaluate the performance of two options of controller implementations ranging from a low-cost microcontroller based embedded system to a relatively high-end, high-cost controller prototyping system. In the work reported here, the Arduino® DUE board, which is an Atmel ARM Cortex CPU based, and the dSPACE® DS1104 prototyping system are used. Another objective of the …


Metamaterial-Based Sensor Design Using Split Ring Resonator And Hilbert Fractal For Biomedical Application, Nadin M. N. Alrayes Apr 2019

Metamaterial-Based Sensor Design Using Split Ring Resonator And Hilbert Fractal For Biomedical Application, Nadin M. N. Alrayes

Electrical Engineering Theses

In this research, a simple and efficient approach is presented to design a metamaterial-based sensitive sensor for biomedical applications. The metamaterial based sensor is designed to differentiate between different types of cancer cell lines based on their electrical properties. The sensor is designed by incorporating a single circular split ring resonator (SRR) and a Hilbert fractal curve. The SRR is used considering its capacitive and inductive resonance properties, thereby making the SRR a favorable candidate for sensing applications. Moreover, the Hilbert fractal curve was used as a defected ground structure to increase sensor sensitivity and selectivity. The Hilbert fractal ground …


Experimental Investigations Of Bio-Syngas Production Using Microwave Pyrolysis Of Uae’S Palm Date Seeds, Mahmmoud Muhammed Syam Apr 2019

Experimental Investigations Of Bio-Syngas Production Using Microwave Pyrolysis Of Uae’S Palm Date Seeds, Mahmmoud Muhammed Syam

Mechanical Engineering Theses

From the start of the industrial revolution, the continued need for energy has been the most crucial issue in human history. An energy crisis started at the beginning of the 1970s when the number of machines, which became an essential part of our life, increased rapidly. Scientists made a huge effort to discover new sources of energy, with ‘biomass’ being one of the main focuses of researchers as a new renewable source of energy. In this thesis, a non conventional method of heating, using microwave power in a pyrolysis process of biomass waste from palm trees (Allig’s date seeds) for …


Production Of Anti-Corrosion Materials From Uae Date Palm Waste, Nour Shehadeh Abdelrahman Apr 2019

Production Of Anti-Corrosion Materials From Uae Date Palm Waste, Nour Shehadeh Abdelrahman

Theses

Palm tree serves as the main source of biomass in the Gulf countries. The United Arab Emirates (UAE) alone is blessed with more than 40 million date palm trees, which generate a huge amount of waste annually. The main objective of this thesis is to examine the ability to produce a corrosion inhibitor from a date palm tree, waste, starting by extracting lignin from different parts of the date palm tree and characterizing the extracted lignin, converting lignin to sodium lignosulfonate, while selecting the optimum condition for the conversion reaction and characterizing the prepared lignosulfonate. Finally, the corrosion efficiency for …


Ultra-Wideband Microstrip Antenna Enhanced Performance Using Metamaterial, Elham K. A Serria Apr 2019

Ultra-Wideband Microstrip Antenna Enhanced Performance Using Metamaterial, Elham K. A Serria

Theses

Antenna engineering is very important in the development of communication systems and the requirements for low profile antennas that cover a wide spectrum of frequencies increase the number of researches in this field. Accordingly, scientists have focused on UWB microstrip antennas that cover the range from 3.1 GHz to 10.6 GHz but others concentrate on enhancing its performance using a special type of materials called metamaterials.

The main objective of this work is to enhance frequency bandwidth, antenna gain, and radiation pattern for the UWB circular microstrip antenna by employing the Split Ring Resonator (SRR) technique, which is one type …


Development Of Biodegradable -Polylactic Acid - Date Palm Waste Composite As Thermal Insulation Material, Mohamed Saeed Barkhad Apr 2019

Development Of Biodegradable -Polylactic Acid - Date Palm Waste Composite As Thermal Insulation Material, Mohamed Saeed Barkhad

Theses

This study aims to develop a green polymer composite from local natural waste, such as date pit powder (DPP) and date palm wood powder (DPWP), as an insulating material. The recycling and reuse of natural waste as filler for green insulation materials has many significant benefits for the environment of the UAE.

Date palm waste was mixed with a polylactic acid (PLA) polymer with various proportions in a melt extruder. The mixtures produced were then shaped differently after testing in a thermal compression machine. These composites were tested to evaluate their physical (water absorption, chemical resistance, and bulk density), thermal …


Investigating Green Inhibitors For Acidic Corrosion Of Carbon Steel, Osama Abu-Alyosr Kamal Ibrahim Apr 2019

Investigating Green Inhibitors For Acidic Corrosion Of Carbon Steel, Osama Abu-Alyosr Kamal Ibrahim

Theses

This study is intended to investigate Khalas palm date pits extract as a green corrosion inhibitor alternative to commercial inhibitors. Inhibition efficiency of the obtained extract was investigated on carbon steel grade S355JR immersed in different corrosive mediums of 2 molarity hydrochloric acid (𝐻𝐶𝑙) solution and seawater solution. Along with other ingredients in palm date pits, Polyphenolic compounds have a significant anti-oxidation property and were found effective in reducing corrosion rate.

Due to its common industrial applications, Carbon steel was used in this investigation as the corroding medium, while 2M 𝐻𝐶𝑙 and seawater solutions were used separately as the corrosive …