Digital Commons Network^™

Traditional And Machine-Learning Equalization Techniques For Bandwidth-Limited Short-Reach Optical Communication Channels, Abdullah Khawatmi

Theses

This thesis investigates equalization techniques for bandwidth-limited short-reach optical communication systems, with a focus on Visible Light Communication (VLC) and Step-Index Plastic Optical Fiber (SI-POF) links. Commercial light-emitting diodes and photodiode receivers impose severe bandwidth constraints, inter-symbol interference, and noise sensitivity, which fundamentally limit achievable data rates. The work addresses these impairments through systematic evaluation of traditional digital signal processing–based equalizers and modern machine-learning-based post-equalization methods. The primary aim of this thesis is to enhance the achievable data rate and reliability of commercial short-reach optical links while maintaining practical computational complexity. Specifically, the objectives are to (i) design and experimentally …

Efficient Energy Management In Networked Microgrids Using Multi-Agent Deep Reinforcement Learning In The Presence Of Uncertainties, Ayodele Benjamin Chukwuyem

Dissertations

Microgrid technology is essential in facilitating the transition to smart energy grids in developed countries and mitigating energy poverty in developing countries, particularly in areas where grid extensions are not feasible. Recently, the concept of networked microgrids (NMGs) has garnered tremendous attention due to the plausibility of interactions among interconnected microgrids leading to power networks that are more resilient, reliable, and stable. However, because each microgrid has diverse distributed generation resources (renewables and controllable generators) and each microgrid operator (MO) has different objectives, coordinated energy management is required to satisfy local and system-wide goals under conditions with significant uncertainty. Existing …

Evaluating Human Rod Photoreceptor Function Using Pixelwise Intensity-Based Optoretinography, Gao Yang, Mina Gaffney, Robert F. Cooper

Biomedical Engineering Faculty Research and Publications

Purpose: More than 50 inherited retinal diseases are known, with rod photoreceptor functional loss serving as an early indicator in nearly half of them. The “optoretinogram” is a relatively new assay that detects optical changes in cells in response to stimuli. This tool has excellent potential for providing insights into the earliest functional changes of rod photoreceptors, with the potential to assist in the early detection, monitoring, and treatment of retinal diseases.

Methods: In this work, we obtained intensity-based optoretinograms (iORGs) from rod photoreceptors using an adaptive optics scanning laser ophthalmoscope. We explore the necessity of both individual rod identification …

Severity And Duration-Dependent Aortic Stiffening In A Rabbit Coarctation Model Identifies Constitutive Material Parameters As Promising Regional Biomarkers For Hypertension Progression, Arash Ghorbannia, Jamasp Azarnoosh, John F. Ladisa Jr.

Biomedical Engineering Faculty Research and Publications

Coarctation of the aorta (CoA) alters hemodynamics and drives regional remodeling, yet the influence of severity and duration on constitutive properties is undefined. We quantified mechanical responses from CoA to identify constitutive parameters capturing stiffening across clinical severities and durations. Mild (≤ 12 mmHg), intermediate (13–20 mmHg), and severe (> 20 mmHg) CoA was created in rabbits for short, long, and prolonged durations (~ 1, 3, or 22 weeks, respectively). Stress–stretch curves from proximal and distal regions were fit with multiple constitutive models (Linear Elastic, Neo-Hookean, Yeoh, Ogden, Mooney–Rivlin, Holzapfel). Model performance was evaluated by normalized RMSE and R², with …

Development And Acceptability Of A Patient Decision Aid For People With Degenerative Cervical Myelopathy: An International Mixed-Methods Study, Andrew R. Gamble, David B. Anderson, Marnee J. Mckay, Benjamin M. Davies, Sophie Macpherson, James Van Gelder, Tammy Hoffmann, Kirsten Mccaffery, Samuel X. Stevens, Carlo Ammendolia, Rohil V. Chauhan, Carl M. Zipser, Timothy F. Boerger, Lindsay A. Tetreault, Michael G. Fehlings, Elanor Dustan, Carolyn Nugent, Helen Holmgren, Andreas K. Demetriades, Justin M. Lantz, Rana Dhillon, Chris G. Maher, Joshua R. Zadro

Biomedical Engineering Faculty Research and Publications

Objectives To develop and user-test a patient decision aid for people diagnosed with degenerative cervical myelopathy and who are considering surgery.

Design Mixed-methods study describing the development of a patient decision aid.

Setting A draft decision aid was developed by a multidisciplinary steering group (including study authors with degenerative cervical myelopathy, health professionals and researchers) informed by the best available evidence, authorship consensus and existing patient decision aids.

Participants Patient-participants and health professional-participants who manage people with degenerative cervical myelopathy were recruited through social media and the steering group’s research and practice network. Quantitative questionnaires were used to gather baseline …

Analysis Of A Coaxial Transmission Line Filled With An Orthorhombic Dielectric-Magnetic Medium, Fathima Manikunnath Abdul Akbar

Theses

Coaxial transmission lines are fundamental means for Transverse Electromagnetic (TEM) wave propagation in RF, microwave and high-speed electronic systems. The study of transmission lines is often familiar when they are filled with isotropic materials; however modern engineered direction dependent materials reshape field distributions. In this thesis, we consider a coaxial transmission line of an inner radius and outer radius b filled with an orthorhombic dielectric-magnetic material, which is described by two anisotropy parameters αx and αy. The potential and field distributions are studied in relation to the ratio b/a as well as the anisotropy parameters αx and αy. Due to …

Breath-Based Detection Of Liver Cancer Biomarkers Using An Swcnt-Fet Nano-Biosensor: Quantumatk, Mohamed Mohieb Rashdan

Theses

Early detection of liver cancer remains limited by the slow pace and invasiveness of current testing methods. This study proposes a single-walled carbon nanotube field-effect transistor (SWCNT-FET) designed to detect hexanal—a volatile organic compound (VOC) elevated in liver cancer—directly from exhaled breath. The device is modeled in QuantumATK using a semi-empirical Extended Hückel Hamiltonian within the non-equilibrium Green's function (NEGF) framework, emphasizing realistic contact physics by employing metallic SWCNT electrodes instead of conventional metal films. Zigzag channels with (11,0) and (12,0) chiralities are examined to analyze how geometry and contact matching influence charge transport. Simulations include current–voltage (I–V) characteristics and …

Development Of A Novel Cfd Approach For Predicting Multiphase Flow Enhanced By Machine Learning, Abdulrahman Elazazi Salem

Theses

Accurate estimation of interface orientation is crucial for ensuring both the accuracy and robustness of Volume of Fluid (VOF) schemes in multiphase flow simulations, especially when using non-uniform Cartesian meshes. Conventional gradient reconstruction approaches, such as least-squares (LSQ) methods, often suffer from significant errors and strong oscillations on highly stretched grids. This work proposes a grid-transferable, learning-based methodology that predicts interface unit normal vectors directly from the local volume-fraction field on nonuniform structured Cartesian grids using a feedforward neural network. The methodology extends earlier work originally developed for uniform grids, which is first reproduced to assess how performance deteriorates in …

Modeling And Autonomous Control Systems For A Delivery Drone Application, Dana Helal Alnuaimi

Theses

This thesis focuses on the development of a multi-drone navigation and control system, aiming to enhance payload capacities beyond the limits of single-drone systems. By integrating multiple drones to work collaboratively as a unit, this study addresses the challenges associated with lifting and transporting heavier payloads.

The primary objective is to design and evaluate a multi-drone system capable of working in tandem to transport larger payloads efficiently. The research aims to develop robust control algorithms, supported by system identification for dynamic modeling, and navigation strategies to enable effective coordination between drones.

The study employs a combination of simulation and real-world …

Study Of The Effect Of Biodiesel Derived From Jojoba Oil With Alcohols Blends On Diesel Engine Performance, Exhaust Emissions, Vibration, And Noise, Yassir Abdelrahman Elbashier

Theses

This study presents a mutual investigation on the properties of the fuels and the performance of an engine using biofuels from mixtures of jojoba oil biodiesel with alcohols. The work consists of mainly two phases, examining the properties of the jojoba biodiesel-alcohols mixtures and the performance and emission behavior in a single piston diesel engine. A base mixture of 50% jojoba biodiesel and 50% diesel produced, and this was fractionally mixed with 5, 10, and 20% methanol and with 5, 10, and 20% diethyl ether (DEE). The rheological properties namely viscosity and shear stresses of all biodiesel blend mixtures were …

A Low-Noise And High-Gain Integrated Photoplethysmography Sensor For Continuous Vital Signs Monitoring, Neethu Mohan

Dissertations

Photoplethysmography (PPG) sensing is an important technology used for measuring health parameters like, heart rate, respiratory rate, blood oxygen saturation, and blood pressure (BP). The PPG sensing is used for individuals who have to periodically monitor their health due to chronic health conditions. The basic requirements of a wearable PPG sensor include non-invasiveness, prolonged battery life, and being userfriendly. These type of sensors have great demand in the healthcare applications and there is a significant rise in the demand of these sensors. The basic objective of these PPG sensors is to make the continuous vital health monitoring easier without the …

A Comparative Study On Performance Of Iot-Driven Ml-Enabled Forecasting Models For Efficient Air Quality Monitoring, Bara Ksiksi

Theses

Air pollution is one of the most critical environmental challenges affecting public health globally, responsible for approximately 4.2 million premature deaths annually according to the World Health Organisation. This thesis presents a comparative study of IoT-driven machine learning forecasting models for air quality monitoring in Abu Dhabi, UAE, introducing a zonal approach combined with satellite-based spatial validation. The primary objective is to evaluate forecasting performance across three distinct activity zones using ground station data from the Environment Agency Abu Dhabi (EAD), and to incorporate a spatial validation component using satellite imagery to assess the consistency of ground-based predictions at a …

Development Of A Benchmark Building Condition Index Utilizing Discrete Facility Subsets For Use In Risk Prioritization Analysis, Christopher A. May

Engineering Management & Systems Engineering Theses & Dissertations

Within the healthcare facilities management arena, key performance-based condition indices such as a calculated Building Condition Index (BCI) are currently utilized as a governing indicator of facility health and performance. However, BCI alone does not adequately support enterprise-level risk prioritization and fails to provide a validated facility-to-facility risk prioritization model. Assets within the same enterprise receiving similar sustainment funding experience different rates of degradation depending on asset type and construction age thus impairing the BCI rating scale. Statistical analysis of facility metrics indicates a strong correlation between facility degradation drivers and prediction of a subset-based benchmark BCI. The research validates …

An Integrated Bayesian Network-Based Zero Trust Model To Quantify Cyber Risk In Small-Medium Businesses, Ahmed Abdelmagid

Engineering Management & Systems Engineering Theses & Dissertations

Small-medium businesses (SMBs) play a pivotal role in the worldwide economy as they constitute the most considerable portion of businesses in developed countries like the UK and the US. As such, SMBs are likely targets of cybercrimes by malicious agents because of their vulnerable IT systems. The digital infrastructure of SMBs is more likely to be hit by cyberattacks than large businesses due to many factors that facilitate hackers’ missions. These factors include a limited financial budget devoted to cybersecurity, a lack of knowledge, an underrating of how dangerous cyber threats are, and a shortage of IT expertise. The enormous …

Workforce Resilience In Public Transportation Agencies, Kristal D. Metro

Civil Engineering ETDs

A strong, resilient public workforce is necessary to keep the United States’ infrastructure system running smoothly. Across the public sector, hiring is lagging behind increasing retirement rates, leaving public agencies facing the loss of institutional knowledge at unprecedented levels. Combined with above-average retirement rates, low unemployment rates, and below-average salaries, workforce shortages are expected to become critical, putting the resilience of the public transportation workforce, and by extension, the United States public infrastructure and services at risk. The purpose of this research is to determine the best practices for recruiting and retaining employees at public transportation agencies, thereby positively influencing …

Downstream Effects Of Post Aerobic Digestion And Divalent Cation Treatment: Dewaterability, Phosphorus Mitigation, And Process Odors, Maya Marisol Quijano Garcia

Civil & Environmental Engineering Theses & Dissertations

This study evaluated post-aerobic digestion (PAD) with aeration, mixing, and divalent cation addition to improve phosphorus capture, dewaterability, and odor control in thermal hydrolysis process (THP)–treated anaerobic digestate at the Hampton Roads Sanitation District’s Atlantic Treatment Plant. A three-day PAD process was operated under constant air flow (5 LPM) and dissolved oxygen (DO)-setpoint (0.2 mg/L) aeration conditions with Ca(OH)₂ or Mg(OH)₂ dosing. Aeration and mixing alone increased polymer demand by 14–46 % relative to untreated influent, indicating enhanced extracellular polymeric substance release. Chemical conditioning partially mitigated this increase but did not restore polymer demand to baseline levels. Dewatered cake total …

Extending The Job Demands-Resource Model In Classified Work Environments: A Longitudinal Analysis Of Job Demands, Resources, Job Satisfaction, And Retention Among Engineers, Gregory Gooden

Engineering Management & Systems Engineering Theses & Dissertations

The Job Demands–Resources (JD-R) model is a widely used framework for understanding how work conditions influence employee attitudes and retention-related outcomes. However, empirical evidence testing JD-R dynamics in classified technical work environments remains limited, particularly using longitudinal designs that account for structural constraints, nonrandom participation, and outcome-specific measurement challenges. Classified work is characterized by persistent demands, restricted flexibility, and security-driven limitations on available resources, raising questions about whether and how JD-R processes generalize to this context.

This study examines whether job demands and job resources predict subsequent job satisfaction and retention intent in a classified technical workforce using multi-wave longitudinal …

Bioengineering The Future Of The Human Species: H+’S Ideological Iterations Of Trans-/Posthumanity As Exemplified By Futurist Literary Texts = (Bio)Technological Solutions For (And/Or) Reification Of Systemic Inequities?, Marjorie E. Bomhower

English Theses & Dissertations

While humanity has, throughout our species’ history, endeavored to dream and create astonishing, and ever-evolving, (bio)technologies with the utopian ideals of bettering our day-to day lives and achieving greater longevity, our endeavors have (thus far) not only produced remarkable, beneficial advances in longevity and quality of life, but have also yielded devastating and dire outcomes; often at the cost and victimization of marginalized communities. This dissertation focuses on select (bio)technologies – particularly, those promoted by H+ (the most current and popular technoutopianist non-profit, “educational,” organization) – with an investigation of current and nascent (bio)technological evolutions, futurist literary texts, and critical/digital …

Natural Convection Of Cuo-Water Nanofluid Flow Along A Vertical Plate With Variable Thermophysical Properties And Discrete Heat Sources, Nepal Roy, Ioan Pop, Rama Subba Reddy Gorla

Faculty Publications

Effects of discrete heat sources along a vertical plate are of practical importance due their occurrence in electronic devices. For growing demand of electronic appliances and their advancement, cooling processes of them must be improved. As usual fluids have limited heat transfer, nanofluids made by dispersing nanoparticles into them are utilized to enhance thermal performance. However, flow characteristics and heat transfer of a nanofluid for discrete heat sources along a vertical plate need to be explored. For this reason, this study analyzes the natural convective heat transfer and flow behaviors of CuO-water nanofluid induced by discrete heat sources along a …

A Theoretical Framework For Recursion In Complex System Governance, Gilbert Goddin

Engineering Management & Systems Engineering Theses & Dissertations

The purpose of this research was to construct an original theoretical framework for understanding recursion in Complex System Governance (CSG), grounded in the propositions and axioms of systems theory and management cybernetics. This framework addresses a research gap for cybernetic recursion relating to the governance of complex systems. Leveraging the CSG framework (Keating & Katina, 2019; Keating, 2022), holonic principles (Koestler, 1970; Mella, 2009), management cybernetics (Beer, 1979; Beer, 1984; Beer, 1995), and metacybernetics (Yolles, 2021; Yolles & Fink, 2015c; Yolles & Frieden, 2021), recursion is theorized as a governable capability, whereby metasystemic governance anticipates emerging complexity and purposefully regulates …

Radiation Protection Factor Research: The Keystone For Conventional-Nuclear Integration (Cni), Andrew W. Decker

Faculty Publications

This article briefly describes Defense Threat Reduction Agency (DTRA) vehicle Radiation Protection Factor (RPF) research and explains its critical role in enabling future Operations in a Nuclear Environment (ONE) and Conventional-Nuclear Integration (CNI) on behalf of the US Department of War (DoW).1 As such, the background and practical utility of RPF values is discussed, as well as the justification for renewed Army and DoW investment into RPF research to enhance Joint military planning, survivability, and lethality on tomorrow’s nuclear battlefields. Advances in DTRA RPF research directly strengthen US strategic and extended deterrence efforts and support all Agencies and Departments responsible …

Comparative Analysis Of Traffic Impact Study Accuracy Using Turning Movement Volume Counts., Kathryn Riopel

Master of Engineering Theses

Traffic forecasting and modeling has been a significant subject of debate within the transportation sector as of the last decade. Transportation agencies and planners use traffic forecasting and modeling in order to predict current and future transportation needs, as well as the impacts of proposed developments. In particular, state departments of transportation (DOTs) and city level agencies often require developers to conduct Traffic Impact Studies (TISes) in order to gauge necessary transport network enhancements to handle new demand from proposed developments. The standards by which these TISes are conducted and judged varies widely, but primarily consists of existing traffic counts, …

An Integrated Tracking Technique For Underwater Navigation Using Acoustic And Imu Measurements, Mainul Islam Chowdhury, Quoc Viet Phung, Iftekhar Ahmed, Daryoush Habibi

Research outputs 2022 to 2026

Accurate navigation is essential for underwater vehicles like AUVs, which often operate in deep or remote areas. However, complex ocean dynamics, cumulative inertial-measurement unit (IMU) drift, and diverse noise sources often result in erratic and unreliable position estimates. To overcome these challenges, we proposed a method that combines underwater acoustic signals with onboard motion sensor data to improve the underwater position tracking system. The proposed system uses a long baseline (LBL) acoustic array of surface buoys to capture the Time-difference-of-Arrival (TDoA) of a multi-pulse beacon. We extract arrival times using a superimposed-envelope-spectrum (SES) detector, which exploits the beacon’s periodic structure …

Condition Monitoring Of Induction Motor Using Motor Current Signature Analysis, Francis Ikechukwu Obianke, Joseph Okhaifoh, Benjamin Akinloye

Al-Bahir

Induction machines serve as the cornerstone and driving force of modern manufacturing and production systems. This research aims to monitor and analyse the operating performance of induction motors using motor current signature analysis (MCSA). MCSA is employed to process the current signal of a motor into a frequency spectrum, known as the current signature by applying the Fast Fourier Transform (FFT) algorithm. The underlying principle is that vibration generated in a motor is closely related to the changes of the magnetic field density, and the induced voltage varies with the stator current.

A simulation model replicating the behaviour of an …

Requirements Of The Elderly In Interior Design Based On A Survey As A First Stage Of Smart Interior Design, Girges Sidhom, Christine Ezzat Danial

HBRC Journal

As the number of the aged in the world is expected to rise dramatically, the built environment should be adjusted to accommodate aging in place, and most of the facilities currently available are inadequate in terms of interior design requirements to support the functional and psychological needs of the aged. The purpose of this study is to establish the design needs of the aged by incorporating smart technology in interior architecture to make them safer and self-reliant. The methodology will apply a descriptive methodology by use of literature review and an analytical approach by use of a questionnaire of 153 …

Design And Construction Of Prestressed Concrete Balanced Cantilever Bridges, Ahmed S. Elareshy, Ashraf M. Osman, Ismail. M. Kamal, Amr A. Abdelrahman

HBRC Journal

Balanced cantilever concrete bridges have recently been widely used in mid and long-span bridges. This paper presents a comprehensive review of the development and design of prestressed concrete balanced cantilever (PCBC) bridges, focusing on research related to real case studies of both precast and cast-in-place box-girder bridges investigated through finite element modeling (FEM) or field measurements. The research strategy targeted peer-reviewed journal articles, conference papers, and technical reports published over the last two decades in major engineering databases. Construction methods, design methodology, and structural behavior of this type of bridge are discussed, alongside key findings on long-term response, dynamic performance, …

Efficiency Comparison Of Reduced Graphene Oxide (Rgo) Composite-Incorporated Polyacrylonitrile Nanofibrous Filters For Respirable Crystalline Silica Dust And Coal Dust, Mahsa Moradi, Ashish Kakoria, Lina Zheng, Guang Xu

Mining Engineering Faculty Research & Creative Works

The health of miners working in underground mines is greatly threatened by their exposure to respirable crystalline silica (RCS) found in coal dust. While coal dust includes RCS, it is important to know the specific filtration efficiency for RCS particles compared to coal dust to improve protective measures. This study compares the filtration efficiency of reduced graphene oxide (rGO) composite-incorporated Polyacrylonitrile (PAN) nanofibrous filters at four different concentrations of rGO (0, 2, 6, and 10 wt.%) for RCS particles and coal dust. The filters were made using the electrospinning method. They were tested separately with RCS particles and coal dust …

The Role Of Transformable Facade Technologies In Enhancing The Architectural Environment Quality In Educational Buildings, Waad Marawan Elashry, Ahmed Eltantawy Elmaidawy, Esraa Elazab

Mansoura Engineering Journal

In recent times, Educational Buildings development has become an increasingly important issue at all locations, even in the areas with the least means. Progress in the field of technology has impacted the development of architecture and modern technologies have provided for the architect enormous possibilities in the formation and design of buildings. The facade of a building plays a crucial role in providing environmental comfort, depending on the type of envelope and design. Architects and engineers need to consider many issues when working with facade designs, including environmental issues, aesthetic appearance, comfort of building occupants, and the view; these aspects …

Neutrosophic Probability With Dynamic Temporal Uncertainty (Nptu), Bhimraj Basumatary, Ashoke Kumar Brahma

Neutrosophic Systems with Applications

This paper introduces Neutrosophic Probability with Dynamic Temporal Uncertainty (NPTU), an extension of classical neutrosophic probability that incorporates the dimension of time. In classical neutrosophic probability, the degrees of truth, indeterminacy, and falsity are considered static. However, real-world uncertainties evolve, and their degrees change as new information becomes available. NPTU models these uncertainties dynamically, allowing for more accurate decision-making in time-varying environments. The paper explores key mathematical properties of NPTU, including entropy, distance measures, similarity measures, and Kullback-Leibler (KL) divergence, to quantify and compare temporal uncertainty states. The proposed framework is demonstrated through a case study on stock price prediction, …

Double-Valued Complex Neutrosophic Graphs, Suriyakumar G, V. J. Sudhakar, Takaaki Fujita

Neutrosophic Systems with Applications

This paper introduces a novel graph-theoretic framework, called the double-valued complex neutrosophic graph, as an extension of double-valued neutrosophic set theory. Within this framework, we investigate several important classes of such graphs, including self-complementary, strong, and full double-valued complex neutrosophic graphs, and establish a number of their fundamental properties. To clarify the proposed concepts and demonstrate their structural behavior, several relevant illustrative examples are also provided.