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Shape Memory Alloy Capsule Micropump For Drug Delivery Applications, Youssef Mohamed Kotb Jun 2024

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 …


Tunable Dual-Phase Dual-Drug Delivery System Using A Plga Microparticle/Pva Hydrogel Composite, Timothy John Eck Apr 2024

Tunable Dual-Phase Dual-Drug Delivery System Using A Plga Microparticle/Pva Hydrogel Composite, Timothy John Eck

Theses and Dissertations

Current drug-eluting coatings have demonstrated controlled long-term, sustained release but have only tried to mitigate short-term burst release as a negative side effect. For applications like wound healing, there is a need for a drug-eluting coating which is adjustable in both short- and long-term release, independent of each other. We present a tunable dual-phase dual-drug delivery coating composed of drug-loaded polymer microparticles and drug-loaded hydrogel which can control short term and long term release individually in this study. This coating was created using lidocaine and dexamethasone encapsulated in poly(D,L-lactide-co-glycolide) particles combined with lidocaine- and dexamethasone-loaded poly(vinyl alcohol) hydrogel. Hydrogel drug …


Modified Coulomb Approach For Squat Silos, Mitchell Cade South Apr 2024

Modified Coulomb Approach For Squat Silos, Mitchell Cade South

Theses and Dissertations

Traditional methods for calculating lateral pressures in silos, such as Janssen's Method and Coulomb's Method, have limitations due to the underlying assumptions of each methodology. This research investigates an approach which adapts Coulomb's Method to account for the cylindrical geometry of silos. The Silo Wedge Method (SWM) distinguishes between two cases based on the aspect ratio (height/diameter) of the silo. Comparative analysis reveals that the SWM accurately matches Coulomb's Method for linear retaining walls when the silo aspect ratio approaches zero. As the aspect ratio increases above 0.25, the SWM exhibits behavior similar to Janssen's Method. This suggests a potential …


A Hybrid Communication System Using 5g Cellular And Ads-B For Uavs In High-Density Airspaces, Coulton Lee Karch Apr 2024

A Hybrid Communication System Using 5g Cellular And Ads-B For Uavs In High-Density Airspaces, Coulton Lee Karch

Theses and Dissertations

Robust communication is required to provide a safe airspace for the large numbers of unmanned aerial systems that are coming to the National Airspace System (NAS). This thesis explores methods for providing robust communication to large numbers of vehicles in the NAS. Automatic dependent surveillance-broadcast (ASD-B) is a transmission system that can transmit to and is currently required on all manned aircraft. Unfortunately, ADS-B suffers connectivity problems when supporting large numbers of unmanned aerial systems (UAS). The 5G Cellular protocol can support large numbers of UAS, but connectivity suffers with an increase in distance and interference. Using a 5G cellular …


Systems, Models, And Simulation For Novel Microfabrication Of Silicon Carbide And Metal Mesh Filters, Hunter R. J. Stevenson Apr 2024

Systems, Models, And Simulation For Novel Microfabrication Of Silicon Carbide And Metal Mesh Filters, Hunter R. J. Stevenson

Theses and Dissertations

As the boundaries of Moore's Law rapidly approach, research is increasingly turning to exotic materials and metamaterials to advance the capabilities of electronic and micromechanical systems. This thesis presents systems, models, and simulation techniques for novel microfabrication in the realms of silicon carbide (SiC) and metal mesh filters. Through the unification of femtosecond laser pulses, high numerical aperture (NA) objective lenses, and system power and motion control, a system capable of achieving arbitrary 3D features without line-of-sight with aspect ratios up to 109:1 in SiC is developed. Additionally, a model of a direct-write femtosecond-laser-ablation fabricated metal mesh filter (MMF) is …


Improving Wifi Sensor Network Security Through Unassociated Device Communication Using Wireless Latency Shift Keying, Jacob Edward Johnson Apr 2024

Improving Wifi Sensor Network Security Through Unassociated Device Communication Using Wireless Latency Shift Keying, Jacob Edward Johnson

Theses and Dissertations

IEEE 802.11 (WiFi) only has two modes of trust--complete trust or complete untrust. The lack of nuance leaves no room for sensors that a user does not fully trust, but wants to connect to their network, such as a WiFi sensor. Solutions exist, but they require advanced knowledge of network administration. We solve this problem by introducing a new way of modulating data in the latency of the network, called Latency Shift Keying. We use specific characteristics of the WiFi protocol to carefully control the latency of just one device on the network. We build a transmitter, receiver, and modulation …


Gps-Denied Localization Of Landing Evtol Aircraft, Aaron C. Brown Apr 2024

Gps-Denied Localization Of Landing Evtol Aircraft, Aaron C. Brown

Theses and Dissertations

This thesis presents a dedicated GPS-denied landing system designed for electric vertical takeoff and landing (eVTOL) aircraft. The system employs active fiducial light pattern localization (AFLPL), which provides highly accurate and reliable navigation during critical landing phases. AFLPL utilizes images of a constellation comprised of modulating infrared lights strategically positioned on the landing site, to determine the aircraft pose through the use of a perspective-n-point (PnP) solver. The AFLPL system underwent thorough development, enhancement, and implementation to address and demonstrate its potential in navigation and its inherent limitations. A proposed method addresses the limitations of AFLPL by using an extended …


Development Of Zr(Iv) Mof-Enabled Nerve Agent Electrochemical Hydrolysis Sensors, Tyler James Marlar Apr 2024

Development Of Zr(Iv) Mof-Enabled Nerve Agent Electrochemical Hydrolysis Sensors, Tyler James Marlar

Theses and Dissertations

Nerve agents are acetylcholinesterase inhibitors and among the most toxic chemical warfare agents ever synthesized. Detection of these chemicals is critical for the protection of populations and strategic resources. G-series nerve agents are volatile compounds. V-series nerve agents are persistent phosphonothioate compounds. Persistent nerve agents do not readily volatilize and can contaminate environmental resources for extended periods. While nerve agents are inherently non-electroactive, they can be hydrolyzed to electroactive products compatible with electrochemical sensing. Zr(IV) MOFs are next-generation nanoporous materials, which have been shown to rapidly catalyze nerve agent hydrolysis. In this work, the catalytic processes of MOF-808, a specific …


Application Of High-Deflection Strain Gauges To Characterize Spinal-Motion Phenotypes Among Patients With Clbp, Spencer Alan Baker Apr 2024

Application Of High-Deflection Strain Gauges To Characterize Spinal-Motion Phenotypes Among Patients With Clbp, Spencer Alan Baker

Theses and Dissertations

Chronic low back pain (CLBP) is a nonspecific and persistent ailment that entails many physiological, psychological, social, and economic consequences for individuals and societies. Although there is a plethora of treatments available to treat CLBP, each treatment has varying efficacy for different patients, and it is currently unknown how to best link patients to their ideal treatment. However, it is known that biopsychosocial influences associated with CLBP affect the way that we move. It has been hypothesized that identifying phenotypes of spinal motion could facilitate an objective and repeatable method of determining the optimal treatment for each patient. The objective …


Time-Dependent Strain-Resistance Relationships In Silicone Nanocomposite Sensors, Alex Mikal Wonnacott Apr 2024

Time-Dependent Strain-Resistance Relationships In Silicone Nanocomposite Sensors, Alex Mikal Wonnacott

Theses and Dissertations

Flexible high-deflection strain gauges have been demonstrated as cost-effective and accessible sensors for capturing human biomechanical deformations. However, the interpretation of these sensors is notably more complex compared to conventional strain gauges, partially owing to the viscoelastic nature of the strain gauges. On top of the non-linear viscoelastic behavior, dynamic resistance response is even more difficult to capture due to spikes in resistance during strain changes. This research examines the relationships between stress, strain, and resistance in nanocomposite sensors during dynamic strain situations. Under the assumption that both macroscopic stress and resistance are governed by microscopic stress concentrations at the …


High Data Rate Signal Processing Architectures And Compilation Strategies For Scalable, Multi-Gigabit Digital Systems, Daniel Alexander Nybo Apr 2024

High Data Rate Signal Processing Architectures And Compilation Strategies For Scalable, Multi-Gigabit Digital Systems, Daniel Alexander Nybo

Theses and Dissertations

In this study we present a high-performance computing architecture and hardware acceleration strategy for a heterogeneous multi-gigabit computing system. The system architecture integrates a BeeGFS distributed file system, capable of achieving 80 Gbps of sustained write throughput across five nodes, essential for managing the high data volumes generated by a 25 high performance computer (HPC) compute cluster. To ensure operational efficiency and scalability, the tasks performed on the Linux compute cluster consisting of 30 nodes are automated using Ansible, facilitating seamless deployment, management, and updates. We present compilation strategies for a hardware accelerated Polyphase Filter Bank (PFB) channelization routine optimized …


Multiscale Characterization Of Dislocation Development During Cyclic Bending Under Tension In Commercially Pure Titanium, Nathan R. Miller Apr 2024

Multiscale Characterization Of Dislocation Development During Cyclic Bending Under Tension In Commercially Pure Titanium, Nathan R. Miller

Theses and Dissertations

Continuous bending under tension (CBT) has been shown to increase room temperature elongation-to-failure (ETF) in various sheet metals past that of simple tension (ST). In commercially pure titanium (CP-Ti) Grade 4, up to 3x extended elongation over ST has been achieved. A greater understanding of deformation mechanisms in CBT would allow for its elongation-enhancing effects to be more fully exploited in HCP and other metals, creating potential for new forming strategies. While most of the extended ETF has been attributed to delayed localization via incremental deformation inherent to the CBT process, together with compressive stabilization and relaxation of mechanical strain …


Investigating Which Muscles Are Most Responsible For Tremor Through Both Experimental Data And Simulation, Daniel Benjamin Free Apr 2024

Investigating Which Muscles Are Most Responsible For Tremor Through Both Experimental Data And Simulation, Daniel Benjamin Free

Theses and Dissertations

Tremor affects millions of people and many patients desire alternative treatment options to medication or neural surgery. Peripheral suppression techniques are gaining greater use, but are currently applied in a trial-and-error method. To optimize these techniques, the muscles most responsible for an individual patient's tremor need to be identified. In this dissertation, I explored two parallel paths that both could aid in identifying muscles responsible for tremor. The first method utilizies measured data and a technique (coherence) that quantifies the frequency dependent correlation between two signals. Using coherence to identify muscles contributing to tremor requires at least two parts: an …


Rfi Mitigation And Discrete Digital Signal Processing Rfsoc Algorithm Implementations For Radio Astronomy And Wideband Communication Systems, Devon Christopher Ward Mar 2024

Rfi Mitigation And Discrete Digital Signal Processing Rfsoc Algorithm Implementations For Radio Astronomy And Wideband Communication Systems, Devon Christopher Ward

Theses and Dissertations

Due to the massive increase of active transmitters broadcasting over wideband frequencies, such as 5G wireless systems, LEO/MEO satellites, satellite constellations, and the increase of IoT devices in the average home, the radio frequency spectrum is becoming more and more congested by interference. Passive receivers face additional challenges due to the growing use of wideband frequency transmissions aimed at boosting communication system throughput. As a result, passive receivers must adopt more robust and intricate techniques to mitigate radio frequency interference. A proposed RFI removal system, known as the true time delay Hadamard projection algorithm, has been introduced in previous work …


Digital Performance Management: An Evaluation Of Manufacturing Performance Management Andmeasurement Strategies In An Industry 4.0 Context, Nathaniel David Smith Mar 2024

Digital Performance Management: An Evaluation Of Manufacturing Performance Management Andmeasurement Strategies In An Industry 4.0 Context, Nathaniel David Smith

Theses and Dissertations

Manufacturing management and operations place heavy emphasis on monitoring and improving production performance. This supervision is accomplished through strategies of manufacturing performance management, a set of measurements and methods used to monitor production conditions. Over the last thirty years the most prevalent measurement of traditional performance management has been overall equipment effectiveness, a percentile summary metric of a machine's utilization. The technologies encapsulated by Industry 4.0 have expanded the ability to gather, process, and store vast quantities of data, creating opportunity to innovate on how performance is measured. A new method of managing manufacturing performance utilizing Industry 4.0 technologies has …


Consumers' Acceptance To Buy And Dispose Of Recycling Textile Products, Roa Alsayed Feb 2024

Consumers' Acceptance To Buy And Dispose Of Recycling Textile Products, Roa Alsayed

Theses and Dissertations

The textile industry is the second most polluting worldwide, following food manufacturing. It is one of the industries that is rarely scrutinized in the Middle East and North Africa (MENA) region. This work analyzes the fashion industry from the perspective of consumer attitudes towards the purchase and disposal of clothing, and their behavior with regards to old garments. The study was conducted in Saudi Arabia and Egypt, two countries that achieved similar results in the fashion industry. The methodology is divided into three phases. First, the manuscript begins with a review of topics such as sustainability, consumer behavior in the …


Prediction Of Distresses In Pavement Networks: A Machine Learning Approach, Mahmoud Kotb Feb 2024

Prediction Of Distresses In Pavement Networks: A Machine Learning Approach, Mahmoud Kotb

Theses and Dissertations

The quality of pavement networks is greatly affected by different distresses. These distresses appear in many forms, such as cracking, potholes, rutting and different types of deformation. As a result, to ensure effective pavement management, accurate modeling of these different distresses has become essential. Moreover, machine learning models have shown great potential in modeling pavement performance in recent years. The objective of this research is to develop machine learning models for modeling key parameters of pavement distress, specifically the International Roughness Index (IRI), fatigue and longitudinal cracking. Data for this investigation were extracted from the Long-Term Pavement Performance (LTPP) database, …


Properties Of Portland Cement Concrete Incorporating Basalt-Based Pozzolanic Cement, Rana Khalil Feb 2024

Properties Of Portland Cement Concrete Incorporating Basalt-Based Pozzolanic Cement, Rana Khalil

Theses and Dissertations

Over the last decade, the world's population has increased dramatically. Due to this growth, the demand for concrete and Portland cement, in return, have increased. Manufacturing of Portland cement is an energy-intensive process that, alone, contributes to about 8% of global CO2. For decades, efforts have been exerted to reduce the harmful environmental impacts of Portland cement by reducing its use in concrete as well as considering alternate binders that may fully or partially replace it. This study aims to assess the properties of concrete incorporating a novel basalt-based pozzolanic cement. To meet this objective, four sets of concrete mixtures …


Assessing Adoption Barriers Of Sustainable Packaging In Egypt, Carol Ramses Morgan Feb 2024

Assessing Adoption Barriers Of Sustainable Packaging In Egypt, Carol Ramses Morgan

Theses and Dissertations

Sustainable packaging has become an essential part of business decisions and corporate directions. With the rise of environmental damages due to improper waste management and unsustainable practices, businesses have a major responsibility to analyze their products’ life cycles and redesign them with sustainability in mind. Applying sustainable packaging could save companies large amounts of resources, therefore cutting costs, while also achieving the legal and social duty as a corporation towards society and the environment. Many developing countries, with specific focus on Egypt, have recently focused on legislative and corporate decisions in order to encourage more sustainable practices. Egypt’s new Waste …


Applicability Of Using Bio-Receptive Concrete For Building Facades In Egypt, Gina Roupheil Feb 2024

Applicability Of Using Bio-Receptive Concrete For Building Facades In Egypt, Gina Roupheil

Theses and Dissertations

The significant increase in carbon dioxide emissions caused by the construction industry is detrimental to our planet. This is rapidly increasing with the urbanization of cities that is gradually taking its toll on the available green spaces, which help in balancing such emissions. Recently, researchers have been trying to make use of bio-receptivity to create biomaterial systems that could be spread on building envelopes and support the growth of small plant species and microorganisms to establish on. Out of those materials, comes the concrete as a promising material for bio-colonization.

Within this context, this study aims at investigating the applicability …


Developing And Forecasting The Egyptian Construction Cost Index, Mayada Elsaied Feb 2024

Developing And Forecasting The Egyptian Construction Cost Index, Mayada Elsaied

Theses and Dissertations

Accurate cost estimation is pivotal for the success of construction projects, yet the industry grapples with challenges related to cost overruns. Uncertainties and unforeseen variables often introduce discrepancies, particularly during the planning phase. Economic changes, considered uncontrollable risks, significantly influence these fluctuations. Various research endeavors have quantified the impact of economic conditions on construction costs, emphasizing the correlation between economic indicators and project expenses. Addressing these challenges, the Construction Cost Index (CCI), a tool introduced by Engineering News Record (ENR), accurately delineates the correlation between economic changes and construction costs. Despite its global efficacy, an Egyptian Construction Cost Index is …


Mri Image Regression Cnn For Bone Marrow Lesion Volume Prediction, Kevin Yanagisawa Feb 2024

Mri Image Regression Cnn For Bone Marrow Lesion Volume Prediction, Kevin Yanagisawa

Theses and Dissertations

Bone marrow lesions (BMLs), occurs from fluid build up in the soft tissues inside your bone. This can be seen on magnetic resonance imaging (MRI) scans and is characterized by excess water signals in the bone marrow space. This disease is commonly caused by osteoarthritis (OA), a degenerative join disease where tissues within the joint breakdown over time [1]. These BMLs are an emerging target for OA, as they are commonly related to pain and worsening of the diseased area until surgical intervention is required [2]–[4]. In order to assess the BMLs, MRIs were utilized as input into a regression …


Fair Fault-Tolerant Approach For Access Point Failures In Networked Control System Greenhouses, Mohammed Ali Yaslam Ba Humaish Feb 2024

Fair Fault-Tolerant Approach For Access Point Failures In Networked Control System Greenhouses, Mohammed Ali Yaslam Ba Humaish

Theses and Dissertations

Greenhouse Networked Control Systems (NCS) are popular applications in modern agriculture due to their ability to monitor and control various environmental factors that can affect crop growth and quality. However, designing and operating a greenhouse in the context of NCS could be challenging due to the need for highly available and cost-efficient systems. This thesis presents a design methodology for greenhouse NCS that addresses these challenges, offering a framework to optimize crop productivity, minimize costs, and improve system availability and reliability. It contributes several innovations to the field of greenhouse NCS design. For example, it recommends using the 2.4GHz frequency …


Study Of Vortices Formation In Lateral Intakes Of Pumping Stations, Muhammad Elgindi Jan 2024

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 …


A 3d Imaging-Based Critique Of Wire Arc Additive Manufacturing (Waam) Simulations, Omar Oraby Jan 2024

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 …


Development Of An Electromagnetic System For Wireless Magnetic Manipulation Of Soft Capsule Endoscope For Drug Delivery Applications, Nada Ashraf Hussein Mahmoud Jan 2024

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 …


Optimization Of Vibro-Seismic Parameters For Enhanced Oil Recovery Application, Tarek Abdel Aal Jan 2024

Optimization Of Vibro-Seismic Parameters For Enhanced Oil Recovery Application, Tarek Abdel Aal

Theses and Dissertations

This thesis was conducted in the American University in Cairo by Tarek Ahmed Abdel Fattah Abdel Aal. The thesis is titled ‘Optimization of Vibroseismic Parameters for Enhanced Oil Recovery Application.’ The thesis discusses whether or not the combination of optimized physical vibration parameters with waterflooding would improve porosity, absolute permeability, relative permeability, and recovery when compared with just classical waterflooding. The optimized physical vibration parameters as well as methodology was used from a previous paper that was performed in conjunction with my thesis advisor on similar core samples. The experimentation was performed on five core samples with different porosities and …


Laboratory Evaluation Of Warm Mix Additives At Lower Than Traditional Compaction Temperatures, Abdelrahman Mahmoud Waheish Ali Jan 2024

Laboratory Evaluation Of Warm Mix Additives At Lower Than Traditional Compaction Temperatures, Abdelrahman Mahmoud Waheish Ali

Theses and Dissertations

The study aims to evaluate the impact of warm mix additives (WMA) on the rheological and performance properties of asphalt binders and mixtures. For this purpose, PG 76-28 and PG 58-28 were obtained with one organic (Sasobit Redux) and three chemical WMA (Rediset, Evotherm, and Zycotherm). All WMA-modified asphalt binders were aged at three different aging levels. Laboratory tests such as performance grade (PG), critical temperature differential (ΔTc), asphalt binder cracking device (ABCD), linear amplitude sweep test (LAS), and Fourier transform infrared spectroscopy (FTIR) were performed. In addition to the binder testing plan, this study also evaluated the impact of …


Integrated Project Delivery (Ipd): A Contractual Framework For The Egyptian Construction Industry, Sarah Hussain Jan 2024

Integrated Project Delivery (Ipd): A Contractual Framework For The Egyptian Construction Industry, Sarah Hussain

Theses and Dissertations

This abstract highlight the significant findings and contributions of the study, which aimed to develop model clauses specifically tailored to the Egyptian construction industry for multi-party construction contracts. The research methodology encompassed several key components. Firstly, a comprehensive literature review was conducted to explore the various construction delivery methods prevalent in Egypt. This review provided a solid foundation for understanding the existing practices and identifying areas for improvement. The study also delved into the concept of Integrated Project Delivery (IPD) and its potential benefits as well as an analysis of the commonly used standard forms of contract and successful case …


Development Of A Xenograft For Annular Repair Using Pulsed Electric Field Exposures For Enhanced Decellularization, Prince Mensah Kwaku Atsu Jan 2024

Development Of A Xenograft For Annular Repair Using Pulsed Electric Field Exposures For Enhanced Decellularization, Prince Mensah Kwaku Atsu

Theses and Dissertations

Severe back injuries and chronic pain necessitate surgical replacement of damaged intervertebral disc (IVD) cartilage in advanced disease stages. Bovine IVD tissue has been exposed to an upper threshold pulsed electric field (PEF) dose, causing cell death without thermal damage to the tissue. Subsequent PEF exposures at lower magnitudes have accelerated the removal of immunogenic biomolecules though electrokinetic extraction using optimized aqueous solutions. This approach yields a natural scaffold, ready for biocompatibility and mechanical strength assessment. The effects of microsecond pulsed electric fields (µsPEF) on primary bovine AF fibroblast-like cells have been characterized in vitro. PEFs of 10 and 100 …