Engineering Commons^™

Identifying Challenges Faced By Small And Medium Enterprises (Smes) In The Middle East And North Africa (Mena) Region Through Total Quality Management, Mohamad Atef

Theses and Dissertations

Recently, Small and Medium Enterprises (SMEs) have become recognized as an important driver of global economic growth and innovation. This phenomenon is particularly evident in the MENA region, where small and medium-sized enterprises (SMEs) make a significant contribution to the businesses. SMEs offer significant benefits in terms of job creation, revenue generation, and fostering economic diversity. Although SMEs have a vital contribution in the economy of the MENA region, SMEs face many challenges that hinder their development and long-term viability. Focusing on these challenges is very important for fostering a vibrant and resilient economic environment. The objective of this thesis …

Development Of A Haptic System For Robot-Assisted Femur Fracture Surgery, Fayez H. Alruwaili

Theses and Dissertations

Robot-assisted surgery has emerged within the field of surgical technology, driven by the need for greater accuracy and speed in the ongoing evolution of healthcare. This advancement has influenced numerous areas requiring enhancements to achieve optimal surgical results. However, surgical robotics tends to lack the surgeon’s connection to the operation, creating a gap in the intuitive skill set required for successful operations. The gap is seen through the lack of sense of touch, which may result in tissue damage and additional injury when the robot interacts with the patient. Furthermore, challenges faced during femur fracture surgery have positioned robot-assisted surgery …

Thermodynamic Modeling Of Uranium Nitride With Select Actinides And Fission Products, Eric Reece Mcmanus

Theses and Dissertations

Uranium mononitride fuel is being investigated as a potential nuclear fuel for a Westinghouse lead-cooled fast reactor due to factors such as its high uranium density, high melting point, and favorable thermal conductivity. To obtain an understanding of the thermochemical behavior of UN fission products and minor actinides, thermodynamic data was obtained from various resources to create a database to represent the behavior of the fuel. This database was used to generate an Ellingham diagram to represent the relative thermodynamic stability of the phases over the reactor temperature range. A simulation was run computing the equilibrium state of the fuel, …

The Effect Of Chromium Coatings On Hydrogen Uptake In Zirconium Alloy Nuclear Fuel Cladding, Jorie Lyn Walters

Theses and Dissertations

The amount of hydrogen in a nuclear reactor can have a profound impact on its performance and safety when it is absorbed into or released from fuel rods. Hydrogen pickup in modern fuel cladding materials has been minimized by alloying additions and microstructural texture engineering, but these materials are still susceptible to hydrogen release during high temperature oxidation. The nuclear accident at the Fukushima Daiichi power plant in 2011 resulted in hydrogen gas production and subsequent explosions which led the United States Department of Energy to initiate a program to develop enhanced nuclear fuel cladding materials. New cladding materials include …

Microchannel Slip Flow Characteristics By Time Travel After Photobleaching Velocimetry, Brandon James Sellers

Theses and Dissertations

Interfacial science follows the study of observing behavior between two or more phases of matter when in contact. For example, a liquid solution passes through a microchannel, and the walls interact with the fluid shearing along the surface. The fluid particles develop momentum changes from interfacial phenomena and slip along the wall begins to affect the fluid body. Slip flow is a name for the phenomenon, and with it, modeling velocity for the interfacial behavior demands both resolution and minimal interference. Laser-induced fluorescence photobleaching anemometry (LIFPA) works as a sound method for acquiring data on microchannel flow, but it needed …

Crystal Plasticity Modeling Of Heterogeneous Microstructure Of Additively Manufactured Metals, Md Mahabubur Rohoman

Theses and Dissertations

Additive manufacturing (AM) has emerged as a promising technique in the manufacturing industry for producing complex metal components as it provides shape freedom and simplistic processing chain.

Powder bed fusion is the widely used AM technique that uses laser or electron beam as the energy source to melt the metal powder and deposit it in a layer-by-layer fashion. While doing so, the previously molten layers are constantly are in re-heating and re-cooling processes which end up creating an intricate solidification for the deposited layers. Due to the complexity involved in the thermal cycles for the solidification process, columnar grains develop. …

A Plug-And-Produce Connectivity Framework For Manufacturing Systems, Theodros Abraham Tarekegne

Theses and Dissertations

The Industrial Internet of Things (IIoT) movement has birthed technologies that enable the fusing of physical and digital environments. However, the extensive number of available options for industrial communication and data formatting has remained a barrier to achieving digital knowledge synonymy in industry. There have been previous attempts to establish standards for industrial connectivity and communication, but legacy machines, as well as custom and non-proprietary devices, still face issues communicating data with other manufacturing equipment. To address these challenges, the Industrial Internet of Things initiative has led to the creation of the Plug and Produce (PnP) concept to facilitate the …

A Holistic Quality Management Model For Optimization Of Quality Assurance In Manufacturing, Devon Blakeney Clark

Theses and Dissertations

Quality Management (QM) is essential in manufacturing to ensure products are consistent and functional every time. Consumers expect high quality products that last, and industries unable to accomplish this are destined to fail. Therefore, product quality has always been at the forefront of manufacturer decision making, though it is normally viewed as a given more than as a goal. This means that businesses want quality because it is needed for their survival, but there has not been consideration for how to incorporate innovation into this essential field. Quality needs to be viewed holistically with regards to all manufacturing factors that …

Experimental And Computational Understanding Of Solid Oxide Iron Air Battery Performance, Chaitali Morey

Theses and Dissertations

Long-duration energy storage (LDES) (10+ hours) is considered a key technical solution for a widespread penetration of renewable energy into the utility market. However, the currently available storage technologies are limited to less than 10 hours for cost reasons. The benchmark Li-ion battery technology would be economically prohibitive if the storage time goes beyond 4 hours. Therefore, developing new low-cost LDES-compatible battery technologies is highly desirable. A solid oxide iron air battery (SOIAB) has been developed which consists of a reversible solid oxide cell (RSOC) and energy storage unit (ESU) of an iron bed. This battery is considered a promising …

Application Of Machine Learning Techniques And The Unscented Kalman Filter To Real-Time Gas Turbine Clearance Prediction, Donald Earl Floyd

Theses and Dissertations

The growth in renewable energy sources and retirement of large baseload coal-fired power stations has led to an accompanying decrease in reliability and security of the electrical grid. Since renewable energy sources are typically non-dispatchable, this can lead to blackouts and/or brownouts for customers. Heavy duty gas turbine power plants (HDGT) offer a solution to this problem. HDGTs are dispatchable, clean, and offer flexibility in the fuel they consume, but operational limitations must be well understood to fully exploit their benefits.

One of the main operational limitations is the tip clearances in the gas turbine. In many cases, the gas …

Deep-Learning Assisted Short-Wave Infrared Hyperspectral Imaging For Microplastic Classification, Melisa Nyakuchena

Theses and Dissertations

Microplastics are small plastics with a size between a few microns and about 5mm. Due to their small size, microplastics can be ingested by living organisms including humans, which has become a global concern and a heated area of research. Various methods have been proposed to detect and characterize microplastics. In this study, we demonstrate a hyperspectral transmission imaging system operating in the short-wave range of 1100 nm–1650nm. The developed system incorporates Fourier-transform spectroscopy (FTS) to acquire a hyperspectral data cube at high spectral resolution and signal-to-noise ratio. Using the developed system, we characterize six types of microplastic powders of …

Disproportionation Of Polysulfides Facilitated By A Bi-Functional Carbon Host In Li-S Batteries, Dantong Qiu

Theses and Dissertations

Lithium-sulfur (Li-S) batteries are regarded as one of the promising alternatives to conventional lithium-ion batteries (LIBs) due to their high theoretical energy density (2600 Wh kg-1), abundant resources on Earth, and low cost of sulfur. Nevertheless, several significant challenges persist in the practical application of Li-S batteries, including the insulating nature of sulfur, volume changes of cathodes, and, most critically, the shuttle effect of dissolved long-chain lithium polysulfide (PS) species during cycling. In this thesis, a novel carbon host for sulfur cathode, derived from natural silk and denoted as NC, was developed. This carbon host possesses excellent cycling performance because …

Study Of Polymer-On-Polymer Cold Spray Deposition Windows Under Apparently Similar Conditions, Ülar Tiitma

Theses and Dissertations

The purpose of this thesis is to explore and expand the capabilities of polymer-on-polymer cold spray demonstrated herein using polyamide 6 (PA6)-based powder and substrates. Experiments were conducted using three different cold spray systems described in this work, permitting more in-depth examination of process response to different cold spray process control parameters, such as nominal system pressure and temperature. Two specific responses of interest were the deposition window (DW) and deposition efficiency (DE) of PA6. The DW was determined by performing several sprays at different calculated particle impact velocities and temperatures. The composite result from these experiments was identification of …

Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb

Theses and Dissertations

Implantable drug delivery devices have many benefits over traditional drug administration techniques and have attracted a lot of attention in recent years. By delivering the medication directly to the tissue, they enable the use of larger localized concentrations, enhancing the efficacy of the treatment. Passive-release drug delivery systems, one of the various ways to provide medication, are great inventions. However, they cannot dispense the medication on demand since they are nonprogrammable. Therefore, active actuators are more advantageous in delivery applications. Smart material actuators, however, have greatly increased in popularity for manufacturing wearable and implantable micropumps due to their high energy …

Study Of Accidental Sliding-Mode Control, April Mary Miller

Theses and Dissertations

The objective of this paper is to examine the Quanser SRV-02 motor servo for the presence of an accidental sliding mode. The SRV-02 is used by undergraduate students to learn basic concepts in controls engineering and will display unexpected sliding mode behavior when its in the “out of box” configuration. To gain a strong background understanding in characteristics of sliding mode, a review of literature on sliding-mode control and sliding mode behavior is completed. Next, a theoretical analysis of the SRV-02 motor servo during the sliding mode is developed. An effort is made to find a Lyapunov function that proves …

Computational Fluid Dynamics Study Of Perforated Monopiles, Mary Kathryn Walker

Theses and Dissertations

Monopiles are used in the construction of offshore wind turbines and typically have a design life of 25 to 50 years. Over their lifecycle, monopiles are exposed to a corrosive saltwater environment, facilitating a galvanic oxidation process that quickly degrades the structure. This process can be mitigated by coating the monopile in a protective barrier and implementing cathodic protection techniques. Historically, monopile designers assumed the interior of the pile would be completely sealed and the galvanic corrosion process would eventually consume all the available oxygen, halting the reaction. However, penetrations made in the pile wall for conduit often leaked and …

Test And Evaluation Model For Midwater Docking Of Autonomous Underwater Vehicles, Parker Baillon

Theses and Dissertations

This research created a Test and Evaluation (T&E) model for midwater Autonomous Underwater Vehicle (AUV) capture. The creation of this model will allow for a better assessment of the feasibility of midwater AUV capture. To achieve this, the T&E model was exposed to various flow conditions to assess stability. Capturing an AUV in midwater, the area below the wave-affected zone to the sea floor, has many benefits for an AUV and its mission. AUVs basing missions from a midwater dock will not be affected by wave motions. A midwater dock can be transported to any mission site and deployed with …

Experimental And Numerical Analysis Of Laminar And Transitional Flow Through Annular Corrugated Pipes, Joseph Russell Sargent

Theses and Dissertations

This dissertation presents studies on pressure loss through annular corrugated pipes to determine a friction factor coefficient using nitrogen. Ten different corrugated pipes’ geometries were evaluated via testing and experimentation. The ratio of corrugation height to inner diameter varied from 0.233 to 0.333 and the ratio of corrugation pitch to inner diameter varied from 0.181 to 0.446. Nitrogen flow rates between 0.25 to 94.4 standard liters per minute were used, resulting in Reynolds numbers, based on the corrugated pipe inner diameter, from 100 to 23,000. The experimental set-up was validated using smooth-pipe pressure loss measurements and the derived friction factor …

The Effect Of Extended Saltwater Absorption And Uv Cure On The Compressive Properties Of Msla 3d-Printed Photopolymer Resin Samples With Printing Variations, Suzanne Dixon

Theses and Dissertations

Liquid Crystal Display (LCD) 3D printers, also known as Masked Stereolithography Apparatus (MSLA), is a type of vat polymerization printing technique that cures liquid resin into a solid object. This technique is relatively new. Consequently, there is a shortage of detailed research on the impact of long-term environmental exposure on the MSLA-printed materials. The research within this document informs engineers and scientists of resin compressive properties after extended exposure to saltwater and ultraviolet (UV) light. Saltwater absorption of the material was analyzed at atmospheric pressure, 30-psi, 60-psi, and 90-psi; the samples reached saturation in saltwater after 56 days. The variation …

Evaluation Of Beach-Fx — Beach Nourishment Planning Model – Miami Beach Case Study, Brennan Chase Banks

Theses and Dissertations

Miami Beach, located on the Southeast coast of Florida, is a concerning location for coastal erosion because of the increasing intensity and frequency of tropical storms, nuisance flooding, and accelerated sea-level rise due to climate change. Miami Beach is famous for its beautiful beaches, making it a location of high interest for tourists, citizens, and investors. It is vital for coastal practitioners to accurately model coastal processes, beach evolution, and storm damage during the planning stage of coastal protection projects. The U.S. Army Corps of Engineers developed the Beach-fx model as a tool for engineers, planners, and economists to …

Development Of An Electromagnetic System For Wireless Magnetic Manipulation Of Soft Capsule Endoscope For Drug Delivery Applications, Nada Ashraf Hussein Mahmoud

Theses and Dissertations

Wireless capsule endoscopy (WCE) is a remarkable diagnostic device that examines the gastrointestinal (GI) tract. The WCE is a small capsule integrated with a camera that is used to visualize the inner mucosa of the GI tract. WCE has been proven to be the most effective method to diagnose GI diseases and GI cancers. The procedure reduces the discomfort and risk compared to conventional endoscopy methods. However, current WCEs lack the ability to take a biopsy or deliver a drug to a specific location. Those therapeutic functions can be introduced by wirelessly controlled WCEs. This thesis introduces an electromagnetic system …

Improving The Energy Efficiency Of Residential Buildings In Egypt Through Whole Building Simulations, Habiba Aly

Theses and Dissertations

Residential buildings consume around 40% of total electricity consumption in Egypt. This research investigates the energy saving potential of the Green Pyramid Rating system (GPRS) and Tarsheed rating system on the building envelopes of mid-rise middle income residential buildings in Cairo through energy modelling and simulation. The study evaluates the economic feasibility of the recommendations of the two rating systems through Life Cycle Cost (LCC), Simple Payback Period (SPP), Discounted Payback Period (DPP), Net Present Value (NPV), and Internal Rate of Return (IRR) Calculations. This research also aims to develop energy efficiency recommendations to achieve 30% energy savings above the …

Cardiac Active Tension Modeling Via Genetic Algorithm-Optimized Fractional Order Systems, Afnan Khaled Elhamshari

Theses and Dissertations

Developing a computational model to model cardiac activity has been increasingly important in recent decades. Accurate cell-level active tension modeling for cardiomyocytes is critical to understanding cardiac functionality on a patient-specific basis and developing an effective in-silico cardiac model. However, cell-level models in the literature fail to account for viscoelasticity and inter-patient variations in active tension. This research proposes a genetic algorithm-optimized, fractional order system to model cell-level active tension by extending Land’s state-of-the-art model of cardiac contraction. The model features the (left) Caputo derivative of six state variables that identify the mechanistic origins of viscoelasticity in a myocardial cell …

A 3d Imaging-Based Critique Of Wire Arc Additive Manufacturing (Waam) Simulations, Omar Oraby

Theses and Dissertations

Residual stresses play a critical role in the mechanical behavior and structural integrity of engineered components. Understanding and quantifying these stresses are essential for ensuring the reliable performance and durability of materials and structures. Traditionally destructive methods are used that involve sample sectioning and material removal. However, non-destructive methods have gained popularity due to their advantages in preserving the specimen's integrity for further testing and material waste reduction. Among these techniques, Digital Image Correlation (DIC) stands out as a powerful non-contact and full-field measurement approach. DIC captures displacements and strain distributions by analyzing the deformation of speckle patterns on the …

Study Of Vortices Formation In Lateral Intakes Of Pumping Stations, Muhammad Elgindi

Theses and Dissertations

The inefficient design of pumping stations leads to undesirable flow characteristics and the formation of vortices in the sump. These undesirable flow features adversely affect the pumping unit performance and increase the operation and maintenance cost. The aim of this thesis is to assess the ability of the Realizable turbulence model to predict the formation of free-surface and submerged vortices within lateral pumping stations’ intakes. Additionally, the study aims to investigate the effect of the flow ratio and bottom clearance on the flow characteristics and the vortices formation in the sump. Finally, the study introduces an assessment of curtain walls …

Insights Into The Characterization And Degradation Of Electrospun Polycaprolactone Scaffolds For Tissue Engineering Applications, Caleb B. Wells

Theses and Dissertations

Electrospun polymeric biodegradable scaffolds are essential in tissue engineering, particularly for Engineered Tissue Vascular Grafts (ETVGs), which promise advancements in treating coronary artery disease, peripheral arterial disease, congenital cardiovascular defects, and renal disease. These scaffolds present a solution to issues with autologous graft availability and durability. While large-diameter grafts in low-pressure environments have seen success, small-diameter grafts in high-flow scenarios remain challenging. Understanding polymeric scaffold degradation and behavior during incubation, especially under dynamic mechanical loading, is vital for clinical translation of small-caliber ETVGs.

This research focuses on characterizing the mechanical and microstructural properties of electrospun polycaprolactone (PCL) scaffolds and their …

Energy Efficient Spintronic Devices For Non-Volatile Memory And Hardware Ai, Walid Al Misba

Theses and Dissertations

Nanomagnetic devices have emerged as a promising alternative to conventional complementary metal-oxide-semiconductor (CMOS) devices due to their low energy dissipation and inherent non-volatility. However, the widespread adoption of these devices requires high-density, high-speed, reliable, scalable, and energy-efficient technologies. This thesis investigates the use of nanomagnetic memory devices as both conventional Boolean memory and multistate memory for hardware AI applications.

Magnetic tunnel junctions (MTJs) are nanomagnetic memory devices that can be switched reliably and energy-efficiently using stress-mediated switching. However, realistic material inhomogeneity and scalability pose challenges for stress-mediated switching of MTJs scaled to lateral dimensions below 50 nm. We demonstrate that …

Extrusion-Based Additive Manufacturing Of Magnetic Heat Exchange Structures For Caloric Applications, Vaibhav Sharma

Theses and Dissertations

Currently, the commercial building sector accounts for 18% of total U.S. end-use energy consumption, of which almost a third was from on-site combustion of fossil fuels for space and water heating. Magnetic heat pumping (MHP) technology is an energy-efficient, sustainable, environmentally-friendly alternative to conventional vapor-compression cooling technology. Several MHP designs today are predicted to be highly energy efficient, on condition that suitable working materials can be developed. This materials challenge has proven to be daunting due to issues associated with intricate synthesis/post-processing protocols and complications related to shaping the mostly brittle magnetocaloric alloys into thin-walled channeled regenerator structures to facilitate …

Borophene And Graphene For Non-Enzymatic Biosensor- Ab-Initio Study, Omar A. Ismail

Theses and Dissertations

Non-enzymatic glucose sensing holds promise to overcome limitations associated with glucose oxidase, such as oxygen dependence and short shelf life. This study explores the potential sensing capabilities of borophene and graphene through direct interaction with various compounds, including β-glucose, uric acid, ascorbic acid, fructose, and acetaminophen. Using Density Functional Theory (DFT), we calculated binding energies and the respective Density of States (DOS) for these adsorbates on both graphene and borophene surfaces. Preliminary results suggest that borophene might exhibit nearly twice the affinity for β-glucose compared to graphene. Moreover, the calculated Density of States reveals distinct distortions in the electronic states …

Fabrication & Characterization Of Hybrid Piezoelectric/Triboelectric Nanocomposite Nanogenerators Via Fusion Deposition Modeling, Khaled El Toukhy

Theses and Dissertations

This thesis aims to discuss the potential of using piezoelectric and triboelectric nanogenerators (PTENGs) for energy harvesting, particularly in the sportswear industry. PTENG's main advantage is that it offers good flexibility making it suitable for high-strain applications. The piezoelectric effect is induced by embedding piezoelectric nanofillers into one of the two triboelectric layers. PTENGs can generate both piezoelectric and triboelectric signals when strained resulting in an enhanced output compared to regular piezoelectric nanogenerators (PENGs) and triboelectric nanogenerators (TENGs). TPU was adopted as the matrix for PTENGs advantageous due to their flexibility, low electrical resistivity, and compatibility with additive manufacturing techniques. …