Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Theses

Discipline
Institution
Keyword
Publication Year
Publication Type

Articles 241 - 270 of 3460

Full-Text Articles in Engineering

The Use Of Electrical Resistance Tomography To Determine The Minimum Agitation Speed For Solids Suspension In Stirred Tank Reactors, Baran Teoman May 2019

The Use Of Electrical Resistance Tomography To Determine The Minimum Agitation Speed For Solids Suspension In Stirred Tank Reactors, Baran Teoman

Theses

Njs, the minimum agitation speed needed to just suspend all the solid particles in a solid-liquid mixture stirred in an agitated vessel, is a critical parameter to properly operate industrial tanks in a large number of industrial operations. As a result, a significant literature on Njs is available. The oldest and the most common method to measure Njs experimentally is that of Zwietering’s (Chem. Eng. Sci., 1958, 8, 244-253), where Njs can be visually obtained by determining when the solids stay at the bottom of the tank for no more than 1-2 seconds before being swept away. Although this has …


Mechanics Of Binder-Particle Interactions In Composite Battery Electrodes, Richard Johnson May 2019

Mechanics Of Binder-Particle Interactions In Composite Battery Electrodes, Richard Johnson

Theses

A study into the particle level mechanics of polymer binder and active material used in composite lithium-ion batteries (LIB) has been conducted. Silicon is highly sought after material that can be used as an active material in a composite anode. Its high theoretical capacity can result in batteries that can store more energy than current LIBs, but high volume expansion of Si during charge/discharge cycles leads to rapid capacity fade and poor cyclic life. Understanding the stress that is generated in the binder and the active material due to the volume expansion has not been fully understood. In this study …


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 …


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 (������) 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 ������ and seawater solutions were used separately as the corrosive …


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 …


Design And Fabrication Of A Remote-Controlled Plane For The Advanced Class Sae Aero Design Competition, Simon Esau Jan 2019

Design And Fabrication Of A Remote-Controlled Plane For The Advanced Class Sae Aero Design Competition, Simon Esau

Theses

The goal of the present research is to optimize the radio-controlled airplane design for the Society of Automotive Engineers International (SAE) Aero Design Advanced Class competition. The SAE Aero Design Advanced Class seeks to further research and development of an aeronautic system that can deliver cargo and passengers to form a colony on Mars. Mission success is achieved by attending to the rules, constraints, and requirements of the competition. System-level engineering is applied to meet these diverse requirements and create a robust final product. The radio-controlled airplane submitted for competition can theoretically be scaled to carry colonists, habitats, and supplies …


Controlled Release Chemical Oxidation: Sodium Persulfate Encapsulated In Pvac Polymer, Mosarrat Samiha Kabir Jan 2019

Controlled Release Chemical Oxidation: Sodium Persulfate Encapsulated In Pvac Polymer, Mosarrat Samiha Kabir

Theses

In this study, sodium persulfate was encapsulated in polyvinyl acetate (PVAc) polymer to investigate the potential of activated persulfate to remediate total coliform and E. coli bacteria from contaminated water through a control release system. Controlled release structures were produced with the polymer and persulfate melted to form pellets at two different baking times. CRP structures containing 60 weight % sodium persulfates blended with 40 weight % polyvinyl acetate (PS- PVAc) were baked for 4 minutes and 10 minutes at 120ºC. The kinetics release of sodium persulfate was studied in a water system and in sand columns. Experimental results showed …


Feasibility Of Integrating Microfluidics Into Point-Of-Care Bio-Diagnostics, Swetha Manoharan Jan 2019

Feasibility Of Integrating Microfluidics Into Point-Of-Care Bio-Diagnostics, Swetha Manoharan

Theses

Potassium in the body needs to be maintained in proper levels for the normal functioning of heart and kidneys. The aim of this work is to develop a simple technique to measure the concentration of Potassium present in a bodily fluid sample, which can be used to assess the health condition of extremely sick patients, especially when the patient's condition needs to be diagnosed and results needs to be obtained rapidly under Point-of-Care settings. Microfluidics is one of the platforms used in bio-diagnostics because of several advantages such as low sample volume requirement and integration into high-throughput screening. In this …


Occupant Evacuation Behavior In Wildfires: Gap Analysis, Agnes Ampomah Jan 2019

Occupant Evacuation Behavior In Wildfires: Gap Analysis, Agnes Ampomah

Theses

This thesis investigates the impacts wildfires have on those who live within the Wildland Urban Interface (WUI) areas. The Fire Protection Research Foundation (FPRF) sponsored this investigation to provide insight on information concerning evacuee pre-movement delays and behaviors before the beginning of an evacuation, both in terms of types of behaviors and elapsed time for these delays. Furthermore, the analysis of evacuee behavior in wildfire past and present evacuations will assist in the construction of future evacuation models that will mitigate evacuee loses during evacuations. The investigation is based on literature reviews on wildfires and their evacuation processes, past and …


Control Of Separated Flow Using A Dielectric Barrier Discharge Plasma Actuator, Mahdi Hasan Jan 2019

Control Of Separated Flow Using A Dielectric Barrier Discharge Plasma Actuator, Mahdi Hasan

Theses

Historically, Dielectric Barrier Discharge (DBD) plasma actuators have shown to be an effective method to control adverse pressure gradient induced boundary layer separation. In this study, a numerical investigation was carried out to explore the effects of a DBD plasma actuator on a three-dimensional incompressible, separated flow. The well-validated National Aeronautics and Space Administration (NASA) wall-mounted hump configuration studied in the simulations, were run at a Reynolds Number of 936,000, based on chord length, and a freestream Mach number of 0.1. The baseline code, CALC-LES, developed by the Chalmers University of Technology was modified to include the effects of the …


Reinforcement Learning Reward Design For Low-Level Controllers, Evan J. Olney Jan 2019

Reinforcement Learning Reward Design For Low-Level Controllers, Evan J. Olney

Theses

The past few decades have produced many successful applications of machine learning. In the area of automated controls, machine learning controllers have been developed to take advantage of the tendency for computers to stumble upon avenues to solutions people either overlooked, or simply do not have the computational capability to explore. Reinforcement learning is a machine learning technique for learning how to choose actions in an environment to increase its expected reward. The reward is the signal that indicates whether or not proper actions were chosen, therefore a behavioral goal is achieved from implicit rewards rather than explicit direction. The …


Investigating A Cyber-Human System For Millennial Caregivers, Ashley Lofton Jan 2019

Investigating A Cyber-Human System For Millennial Caregivers, Ashley Lofton

Theses

Research indicates that most caregiving of persons with dementia (PwD) is done by adults 49 years of age and older. However, millennials make up 25% of the estimated 44 million caregivers in the United States. Although the definition varies, “millennials” for this research is defined by those born between 1984 - 2000, which aligns with the research by Strauss and Howe (2003). Millennial caregivers are taking on this task as their parents or grandparents get older and diagnosed with dementia. Taking on the task of caring for a loved one with dementia can present itself as difficult because of competing …


Mesoporous Bimetallic Oxides Supported Mono And Bimetallic Catalysts For Fischer-Tropsch Studies In A Stainless-Steel Microchannel Reactor, Robert Stevens-Boyd Jan 2019

Mesoporous Bimetallic Oxides Supported Mono And Bimetallic Catalysts For Fischer-Tropsch Studies In A Stainless-Steel Microchannel Reactor, Robert Stevens-Boyd

Theses

Fischer-Tropsch (F-T) synthesis is the controlled catalyzed conversion of synthesized (syn) gas, a mixture of hydrogen and carbon monoxide, to fuel grade alkanes or hydrocarbons. One of the objectives of NSF-CREST Bioenergy Center is to develop stable catalysts for F-T synthesis with the goal of conversion of syngas enriched with CO2 in microchannel microreactors to liquid fuels. In our previous work, the effect of silica and titania sol-gel as support for F-T studies using syngas (CO:H2; 1:3 or 1:2) was investigated and significant differences in the activities of Co, Fe, and Ru catalysts were observed. In order to investigate synergistic …


Feedback Control For Leader Follower Architecture Of Unmanned Arial And Ground Vehicles, Mahmoud El Mahmoud Jan 2019

Feedback Control For Leader Follower Architecture Of Unmanned Arial And Ground Vehicles, Mahmoud El Mahmoud

Theses

This thesis presents development of a feedback controller for a cooperative mission using unmanned aerial vehicle and unmanned ground vehicle. This developed controller offers a solution to the time delayed collaborative autonomous systems for multiple robot systems. There are many motivating applications for these missions including exploration, search and rescue in damaged areas. The architecture developed in this thesis consists of an unmanned ground vehicle as a leader and an unmanned aerial vehicle as a follower. To be specific, the unmanned ground vehicle navigates through a damaged environment and leads the mission. The unmanned aerial vehicle follows the leader and …


Modelling And Simulation Of Renewable Technologies For Economic And Environmental Analysis And Optimization Of Dairy Farms, Michael Christopher Breen Jan 2019

Modelling And Simulation Of Renewable Technologies For Economic And Environmental Analysis And Optimization Of Dairy Farms, Michael Christopher Breen

Theses

The aim of this thesis was to develop a dairy optimisation platform to optimise investments in dairy farm technology and changes to on-farm management practices and electricity tariffs, in order to maximise profitability and minimise environmental impacts. Increased dairy herd sizes and milk production levels in Ireland as well as changing regulations concerning emissions, renewable penetration and energy efficiency have necessitated a means of financial decision support for farmers. Therefore this body of work focused on the creation of a comprehensive method for optimising dairy farm technology selection, management practices and electricity tariffs. The measures which could be implemented on …


Decarbonising The Automotive Industry: The Future For Irish Motorists., Robert Maher Jan 2019

Decarbonising The Automotive Industry: The Future For Irish Motorists., Robert Maher

Theses

This research study is an examination of the current state of the Irish automotive industry, which is being reshaped by the imminent shift to electric vehicles. This transition is designed to assist in solving Ireland's air quality and environmental challenges in line with the worldwide move to combat climate change. The research topic of the decarbonisation of the automotive industry determined the research question: "Decarbonising the Automotive Industry: The Future for Irish Motorists". This inquiry focuses on private cars owned for social, pleasure and domestic use. Secondary research was completed to verify the most prevalent and current existing information. A …


Design Of Dual-Band Rf-Dc Rectifier And Dc-Dc Boost Converter For Energy Harvesting Applications, Merghani K. Merghani Jan 2019

Design Of Dual-Band Rf-Dc Rectifier And Dc-Dc Boost Converter For Energy Harvesting Applications, Merghani K. Merghani

Theses

Wireless sensors are used in many industrial and commercial applications. However powering up those sensors is challenging, because batteries have limited lifetime, require periodic maintenance, and their depositions are toxic to the environment. One of the new methods to power up those small sensors is to capture energy from ambient sources and convert it into a steady dc output voltage, which is known as energy harvesting or scavenging. In this thesis, we propose an energy harvesting method by scavenging the electromagnetic (EM), or radio frequency (RF) energy in the ambient and converting it into a steady dc output voltage that …


Comparison Study Of Supervised Machine Learning Algorithms For Real Time Prediction Of Uav Behaviors, Brian Baity Jan 2019

Comparison Study Of Supervised Machine Learning Algorithms For Real Time Prediction Of Uav Behaviors, Brian Baity

Theses

An American scientific writer/critic of the mid-20th century, Joseph Wood Krutch, stated, “Technology made large populations possible: large populations now make technology indispensable.” Unmanned aerial vehicles (UAVs) have become a vital part of society, evolving from solely military use to commercial and even personal day-to-day use. UAV application has grown for mobility on demand, increasing the number of UAVs in the sky. Consequently, more UAVs increases the possibility of aerial collisions, challenging the safety of passengers flying and bystanders on the ground. Understanding the behavior of UAVs and unmanned aerial systems (UAS) in general, therefore, will decrease the possibility of …


Passive Cooling In Non-Residential Nearly Zero Energy Buildings: A Thermal Comfort Analysis Based On Measurement, Modelling And Simulation, Adam O'Donovan Jan 2019

Passive Cooling In Non-Residential Nearly Zero Energy Buildings: A Thermal Comfort Analysis Based On Measurement, Modelling And Simulation, Adam O'Donovan

Theses

Overheating in non-residential nearly zero energy buildings (nZEBs) presents a major risk to the well-being, productivity and thermal satisfaction of the people who occupy them. As global temperatures are expected to increase in the future, the overheating risk and cooling demand is also expected to increase. Therefore, low cost and low energy solutions that are able to maintain thermally comfortable conditions without the need for mechanical systems will be vital in decarbonising the building stock and ensuring that buildings are comfortable and remain low carbon now and in the future. Passive cooling has long been championed as a low cost …


Experimentally Linking Head Kinematics To Brain Deformation, Imouline Algharbi Jan 2019

Experimentally Linking Head Kinematics To Brain Deformation, Imouline Algharbi

Theses

Traumatic brain injury (TBI) research is used to study the effects of brain injuries and the rehabilitations for them. TBI contributes to major cause of disability and deaths quantifying up to 30% of all the head injuries. To mimic real world impact to understand the mechanism of injury head-surrogate models are used. This thesis describes a method to record head kinematics from acceleration and angular rate sensors of head-brain surrogate model for blast and blunt injury. This methodology is validated through experimental testing. To get a better insight of the head kinematics experienced by a real skull a drop tower …


Optical Properties Of Polymers And Their Applications, Samiha Hossain Jan 2019

Optical Properties Of Polymers And Their Applications, Samiha Hossain

Theses

The last decade has witnessed explosive growth in the world of photoactive polymers for a variety of applications in several sectors of the global economy. The need for efficient, reliable, and low-cost data acquisition, storage, processing, transmission, and display technologies has made it necessary for research aimed at addressing these needs. Recent accomplishments in this materials area represent exciting opportunities for major innovations in various fields. However, further work needs to be done to transfer the technology from fundamental R&D to manufacturing. The goal of this study is to provide a better understanding of the optical properties of polymers and …


Assignment Of E-Commerce Orders To Fulfillment Warehouses, Ahmad Basem Zamka Jan 2019

Assignment Of E-Commerce Orders To Fulfillment Warehouses, Ahmad Basem Zamka

Theses

For large e-commerce companies such as Amazon, when an order comes, this order might be available at more than one fulfillment centers. Therefore, the question of which fulfillment center this order should be fulfilled from would arise.

In a typical situation, customer demand is fulfilled from the closest fulfillment center. However, this approach does not always provide the optimal solution since there are so many factors that could be involved in making such a decision. These factors might include inventory balance, product correlations, and future demand.

Our decision model focuses on putting future orders in consideration while assigning orders to …


Longitudinal Investigation Of Disparity Vergence In Young Adult Convergence Insufficiency Patients, Patrick C. Crincoli Jan 2019

Longitudinal Investigation Of Disparity Vergence In Young Adult Convergence Insufficiency Patients, Patrick C. Crincoli

Theses

Vergence is a form of eye movement in which the eyes move in opposite directions to minimize retinal disparity. It allows an object at different distances from a viewer to appear single during binocular vision by centering the image on the fovea of each retina. Convergence insufficiency (CI) is a binocular disfunction in which blurry and double vision is a symptom. Office-based Vergence/Accommodative Therapy (OBVAT) has been shown to be effective in treating CI. A randomized clinical trial was designed to study fifty participants with CI before and after therapy using randomized therapy treatment (active and placebo), standardized clinical definitions, …


Effect Of Turbostratic Orientations And Confined Fluid On Mechanical Strength Of Bi-Layer Graphene: A Molecular Dynamics Study, Nil B. Dhankecha Jan 2019

Effect Of Turbostratic Orientations And Confined Fluid On Mechanical Strength Of Bi-Layer Graphene: A Molecular Dynamics Study, Nil B. Dhankecha

Theses

The rise of graphene as a reinforcement material in the last decade has been exponential owing to its superior mechanical properties. This one atom thick 2D material is applicable in many industries related to nanomechanical, nanoelectronics and optical devices. Despite its strength and superior properties, single-layer graphene tends to be unstable in a free-standing form. This led to active use of bi-layer and multilayered graphene in many of the above-stated applications. Though properties of single-layer graphene have been extensively investigated both computationally as well as experimentally for over a decade, bilayer graphene and its turbostratic form are still under research. …


Mechanical Design Automation: A Case Study On Plastic Extrusion Die Tooling, Allen Prasad Varghese Jan 2019

Mechanical Design Automation: A Case Study On Plastic Extrusion Die Tooling, Allen Prasad Varghese

Theses

The Skills Gap in Mechanical Engineering (ME) Design has been widening with the increasing number of baby boomers retiring (Silver Tsunami) and the lack of a new generation to acquire, practice and perfect their knowledge base. This growing problem has been addressed with several initiatives focused on attracting and retaining young talent; however, these types of initiatives may not be timely for this new group to be trained by an established Subject Matter Expert (SME) group. Automated Engineering Design provides a potential pathway to address not only the Skills Gap but also the transfer of information from SMEs to a …


Analysis Of 3d Printed Ndfeb Polymer Bonded And Organic Based Magnets, Chimaobi Ibeh Dec 2018

Analysis Of 3d Printed Ndfeb Polymer Bonded And Organic Based Magnets, Chimaobi Ibeh

Theses

Additive manufacturing (AM), or commonly known as 3D printing, has introduced to the manufacturing and commercial sectors novel ways of reducing production times, decreasing material waste, and enabling end products with multi-material configuration and complex geometric designs. From industrial scale to customer-based printers, AM has revolutionized the approach to manufacturing, prototyping, and designing in the field of medical, automotive, aerospace, biomedical, electronics and customizable products. Recently, additive manufacturing has crossed over to the area of applications in magnetism due to the economic push for the miniaturization of electronic and mechanical devices, reduction in production costs and material & design flexibility. …


Icing Thickness Prediction Model For Overhead Transmission Lines, Yue Ming Dec 2018

Icing Thickness Prediction Model For Overhead Transmission Lines, Yue Ming

Theses

Failures in a large electric power system are often inevitable. Severe weather conditions are one of the main causes of transmission line failures. Using the fault data of transmission lines of Shaanxi Power Grid from 2006 to 2016, in conjunction with meteorological information, this paper analyses the relationship between the temporal-spatial distribution characteristics of meteorological disasters and the fault of transmission lines in Shaanxi Province, China.

In order to analyze the influence of micro-meteorology on ice coating, a grey correlation analysis method is proposed. This thesis calculates the grey relational between ice thickness and micro-meteorological parameters such as ambient temperature, …


Amorphous Metal Oxide Semiconductor Thin Film Transistors For Printed Electronics, Mustafa Mohammad Yousef Dec 2018

Amorphous Metal Oxide Semiconductor Thin Film Transistors For Printed Electronics, Mustafa Mohammad Yousef

Theses

There is an acute market need for solution-processable semiconductor inks that can form the essential components of the printed analog and digital circuits. Currently, the industry is migrating beyond simply printing conductive metals for interconnects and embracing higher integration by printing transistors directly on the same substrate. This thesis focuses on investigating solution-processed amorphous indium gallium zinc oxide (IGZO) as a semiconducting channel layer of a field-effect transistor to enable low-cost, large-area printed electronics that are physically flexible and optically transparent. Specifically, we aim to achieve field-effect mobility exceeding 1 cm2/Vs, to overcome the limits faced in existing …