Engineering Commons^™

Application And Suitability Of Using Paraffin Wax In A Thermal Store For Residential Buildings In The Uk, Cameron Edwards

The Plymouth Student Scientist

Heating costs and pressure to reduce carbon emissions are rapidly increasing. A possible solution is the implementation of efficient energy storage systems for UK residential buildings. Paraffin wax-based thermal energy storage offers a promising solution due to its low-cost, high-energy density, and long-term stability. However, its low thermal conductivity significantly reduces its practicality. Multiple upgrades, such as implementing highly conductive particles and nanotubes, have been previously studied but lack the inclusion of cost-effectiveness and real-world feasibility. This paper reviews current research and develops a numerical model using the Enthalpy method and a 2D finite difference approach, utilised in Python. It …

Vacuum-Assisted Resin Transfer Moulding (Vartm): Can Ultrasonic Vibration Decrease Fill Time, Increase Composite Properties, And Reduce Void Formation, Iulia D. Precup

The Plymouth Student Scientist

This study investigated the potential of ultrasonic vibration (28 kHz) to optimize the Vacuum-Assisted Resin Transfer Moulding (VARTM) process. The aim was to assess whether introducing ultrasonic vibration during the resin infusion phase could reduce fill time, improve mechanical properties, and minimize void formation in glass fibre-reinforced polyester composites. Two flexible tooling systems were compared: a reusable silicone membrane and a traditional vacuum bag. Composite plates were manufactured with and without ultrasonic vibration for both systems. Fill time was observed, and post-cured samples were subjected to mechanical testing for flexural modulus, flexural strength, and interlaminar shear strength (ILSS). Void content …

Scaling Wind Farm Layout Optimisation To Meet Uk Energy Demands, Grace Richardson

The Plymouth Student Scientist

This research aims to explore the Wind Farm Layout Optimisation Problem (WFLOP) through both single- and multi-objective optimisation, to show that it can be used to create farm layouts that provide enough power for all homes in the UK. We highlight the intricacies of the problem, including the application of different algorithms and models, and the challenges of scaling the models to achieve optimal results. We employ both a Hill Climbing Algorithm (HCA) and an evolutionary algorithm (NSGA-II) to obtain wind farm layouts, and compare these to the well-known results proposed by Mosetti et al. Moreover, we present a novel …

Design And Validation Of An Industrial Out-Of-Plane Permeability Test Rig Of Fibre Preforms For The Development Of Next Generation Aircraft Structures, Callum Park

The Plymouth Student Scientist

Despite composites comprising 50% of modern aircraft structures, the absence of a standardised method for measuring out-of-plane permeability frequently results in manufacturing defects in early-development aerospace components, directly impacting safety, manufacturing efficiency and costs. This study aimed to address this gap, by designing and commissioning a compact, vacuum-assisted, mass flow test rig, capable of evaluating the saturated out-of-plane permeability of a variety of materials. This design incorporated learnings from theory, previous studies and discussions with industry experts. E-glass, a Metyx unidirectional carbon and the Teijin ITS55 carbon were investigated, where E-glass exhibited the highest permeability of 1.88E-12m², while …

Ai-Driven Electromagnetic Design And Performance Prediction Of Microstrip Antennas, Eduardo Javier Vazquez

Theses and Dissertations

This thesis investigates the application of Deep Learning to automate and accelerate microstrip antenna inverse design. The initial investigation was to predict microstrip antenna performance from its geometry parametric input, and found out that forward prediction with adopted geometric representation results in ill-posed scenario, high ambiguity and unstable mapping. The study later mostly focuses on the inverse prediction by machine learning from S11 parameter input to predict antenna patch geometry parameters instead.

A dataset of 5,000 ANSYS HFSS simulated antennas (later filtered to 4,136 valid samples) was generated using cubic spine -described geometry profiles. Multiple neural architectures were adopted for …

Boundary-Layer Mechanisms In Flow Over Triangular Porous-Textured Flat Plates: A Computational Fluid Dynamics Study, Luis Angel Alvarez

Theses and Dissertations

Growing demand for energy-efficient vehicles drives research into flow control strategies that mitigate aerodynamic drag. Active devices such as morphing flaps or plasma actuators offer real-time authority but require external power. Passive concepts, including riblets, tubercles, porous coatings, and miniature vortex generators, reshape the boundary layer without additional energy input. We propose an integrated passive solution called Triangular Porous Texturing (TPT). TPT combines the two mechanisms: a periodic array of triangular prisms that generate controlled streamwise vortices, and an embedded porous matrix that locally adjusts pressure gradients near the wall. Acting synergistically, these features attenuate near-wall turbulence, redistribute momentum, and …

Development And Testing Of A Prototype Erbium-Doped Lithium Tantalate Based Sensor For Infrastructure Crack Detection And Measurement, Alejandro Barrera

Theses and Dissertations

Ensuring the safety and longevity of infrastructure is crucial to safeguarding communities and preserving economic stability. In this study, the development of a novel sensor for detecting and characterizing cracks in infrastructure, particularly suited for deployment on Unmanned Aerial Vehicles (UAVs), is presented. The device utilizes a laser (operating at 980 nm) for excitation of erbium-doped lithium tantalate nanoparticles that emit 1550 nm wavelength, which stimulates a photodiode for data collection. The data was utilized to collect, process, and reconstruct topological information. The synthesized lithium tantalate nanoparticle samples vary in erbium doping percentages of 0.5%, 3%, and 10%. Experimental evaluation …

Building Services Engineering November/December 2025

Building Services Engineering

No abstract provided.

Assessing Technology Adoption In The Construction Industry, Lucas D. Gibbons

Construction Management

The construction industry is steadily integrating new technologies, yet adoption varies widely depending on company size, market sector, and internal readiness. This study examines how common technologies such as drones (UAVs), Building Information Modeling (BIM), robotics and automated equipment, laser scanning/LiDAR, AI-driven scheduling or analytics tools, and augmented or virtual reality (AR/VR) are being applied in practice, and what benefits they are delivering to construction organizations. To better understand the factors shaping adoption, a survey was administered to members of the CMAC (Construction Management Advisory Council) board representing a range of contractors and industry stakeholders. The survey assessed current technology …

Extreme Bandgap Recessed-Gate Metal Oxide Semiconductor Heterostructure Field Effect Transistors With Drain Current 0.28 A Mm−1 And Threshold Voltage −1.5 V, Abdullah Al Mamun Mazumder, Abdullah Mamun, Kenneth Stephenson, Kamal Hussain, Tariq Jamil, Grigory Simin, Asif Khan

Faculty Publications

Herein, the first demonstration of hybrid high-k oxide (ZrO2-Al2O3) incorporation into extreme bandgap (EBG) Al_0.87Ga_0.13N/Al_0.64Ga_0.36N metal-oxide-semiconductor heterostructure field-effect transistors (MOSHFETs) is presented, with both planar and recessed-gate designs on the same AlN/sapphire template with a state-of-the-art low contact resistance of 1.4 Ω mm (contact resistivity, ρc ≈ 5.7 × 10−6 Ω cm2). The recessed-gate MOSHFETs achieve a threshold voltage shift of ΔVTH = 5.8 V, highlighting improved channel control. Static output measurements reveal a peak drain current (IDS) of 340 mA mm⁻¹ for the planar …

Property Management System, Abbas Kurnool

Electronic Theses, Projects, and Dissertations

The real estate industry generates and manages large amounts of data, including tenant information, lease agreements, property maintenance schedules, and financial transactions. Reliance on traditional manual methods often results in inefficiencies, fragmented data, and delays in decision-making. To overcome these challenges, this project presents the design and implementation of a Real Estate Property Management System (REMS) for Future Properties, a company aiming to optimize its operations through digital transformation.

The proposed system is developed on Microsoft Dynamics 365 as the core platform, integrated with the Microsoft Power Platform tools (Power Apps, Power Automate, and Power Pages). This integrated framework provides …

2025 Summer-Fall Graduate Recognition Program, Propulsion Research Center, Robert Frederick

PRC Graduate Recognition

This program includes the graduate recognition program for summer and fall 2025. Includes photographs, upcoming events, recent publications, and student profiles.

Porous Triboelectric Nanogenerator For Load Sensing Of Total Knee Replacement, Elham Mahmoudi, Adam Garry Redgrift, Emre Salman, Milutin Stanacevic, Ryan Willing, Shahrzad Towfighian

Mechanical Engineering Faculty Scholarship

This study addresses the critical need for self-powered, durable pressure sensors in Total Knee Replacement (TKR) implants to enable the collection of post-operative information. The scope of this research encompasses the design, development, and testing of a triboelectric nanogenerator (TENG) integrated into an instrumented knee implant for energy harvesting and pressure sensing. The authors’ unique approach involves utilizing a porous silicone rubber as a dielectric material. This allows the TENG to withstand forces up to 2000 N and generate a maximum power output of 18 μW. Theoretical modeling combined with experimental validation provides deeper insight into the fundamental operating principles. …

Bridging Cybersecurity Practice And Law: A Hands-On, Scenario-Based Curriculum Using The Nice Framework To Foster Skill Development, Colman Mcguan, Aadithyan Vijaya Raghavan, Komala M. Mandapati, Chansu Yu, Brian Ray, Debbie Jackson, Sathish Kumar

Electrical and Computer Engineering Faculty Publications

In an increasingly interconnected world, cybersecurity professionals play a pivotal role in safeguarding organizations from cyber threats. To secure their cyberspace, organizations are forced to adopt a cybersecurity framework such as the NIST National Initiative for Cybersecurity Education Workforce Framework for Cybersecurity (NICE Framework). Although these frameworks are a good starting point for businesses and offer critical information to identify, prevent, and respond to cyber incidents, they can be difficult to navigate and implement, particularly for small-medium businesses (SMBs). To help overcome this issue, this paper identifies the most frequent attack vectors to SMBs (Objective 1) and proposes a practical …

Multi-Modal Data-Efficient Learning For 3d Machine Vision, Zhimin Chen

All Dissertations

The rapid progress of 3D computer vision has enabled a wide range of applications in autonomous driving, robotics, and augmented reality. Despite this growth, training robust 3D perception models remains challenging due to limited labeled data, the complexity of integrating multiple modalities, and the inherently imbalanced and long-tailed nature of 3D datasets. This dissertation addresses these challenges by proposing data-efficient, multi-modal learning frameworks that improve the accuracy, generalization, and scalability of 3D scene understanding.

In the semi-supervised setting, this work presents novel approaches that combine limited annotations with large amounts of unlabeled data to enhance 3D object classification and retrieval. …

Synthesis And Characterization Of Chemically Recyclable Polypropylene-Based Covalent Adaptable Networks, Andrii Tiiara

All Dissertations

Polyolefins (POs) are inexpensive engineering materials with excellent physical and mechanical properties, accounting for nearly 60% of all thermoplastics. However, large-scale recycling remains limited, with only ~15% undergoing mechanical recovery. This dissertation addresses this challenge by fragmenting and functionalizing polypropylene (PP) chains to generate macromonomers and employing them, along with industrial reactive PP macromonomers, to synthesize, depolymerize, and repolymerize chemically recyclable polypropylene-based polyolefins (CR-POs). These CR-POs incorporate ester linkages that form covalent adaptable networks (CANs), maintaining a gel fraction of ~70% while remaining melt-reprocessable via extrusion and compression molding.

First, the fragmentation of PP is investigated by microwave irradiation. Microwave …

Robust Data-Driven Predictive Control Of Nonlinear Systems Under Modeling Uncertainty, Pegah Ghafghanbari

All Dissertations

Data-driven predictive control enables designing controllers directly from data, making it attractive for complex systems with hard-to-model dynamics. However, practical deployment is challenged by modeling inaccuracies and changing operating conditions. This dissertation develops predictive control frameworks that incorporate robustness and adaptability to address these issues in uncertain nonlinear systems.

The first part employs the Linear Parameter-Varying (LPV) framework, which represents nonlinear dynamics through simple linear form representation. To characterize the plant-model-mismatch often caused by limited data and numerical calculations, Bayesian Neural Networks (BNNs) are used, and their uncertainty estimates are integrated into two robust control approaches. The first is a …

Surface Reaction And Transportation Of Radium-226 In Marine Systems, Jiusi Wang

All Dissertations

Historical uses of radium (Ra)-containing self-luminous paint, such as on gauges and dials in naval ships, have led to the potential for such paint, and thus Ra, to be released into the marine environment. Radium-226 (²²⁶Ra) behavior in marine systems is not fully described in the literature, presenting a knowledge gap in the process of evaluating potential ecological impact of Ra in marine systems. This study explores various mechanisms contributing to Ra environmental transport in marine systems on a laboratory scale, including leaching, sorption, and diffusion. ²²⁶Ra leaching from watch hand dials containing radioactive luminous paint is …

Advancing Life Cycle Assessment Of Mass Timber: Environmental Performance, Circular Design And End-Of-Life Strategies, Muzan Williams Ijeoma

All Dissertations

Mass timber has emerged as a leading candidate for low-carbon construction, offering the dual benefits of reduced embodied emissions and biogenic carbon storage. Yet, fully realizing its sustainability potential requires a comprehensive and context-specific understanding of its environmental performance across the entire life cycle, from raw material production to building operation and beyond end-of-life (EoL). This dissertation advances life cycle assessment (LCA) practices for mass timber by addressing critical challenges across multiple phases of its life cycle. This dissertation is comprised of three published papers, and two submitted manuscripts. First, I conducted a critical review and meta-analysis of mass …

Hydrodynamics Of Perforated Heave Plates, Muhammad Usman

All Dissertations

Ocean waves are a clean and renewable energy source that can help reduce dependence on fossil fuels and combat climate change. To capture this energy, researchers have developed devices known as wave energy converters (WECs). One common type, called a two-body point absorber WEC, uses a buoy floating on the ocean surface connected to a submerged reaction plate, known as the heave plate, which lies underwater. The relative up-and-down motion between the buoy and the heave plate, driven by ocean waves, generates usable power via a power take-off (PTO) system. Traditionally, these submerged heave plates are solid structures. However, this …

Opposed-Piston Two Stroke Engine As A High Power Density Solution In Heavy Duty Applications: An Experimental Evaluation With Diesel And Ethanol, Ankur Bhatt

All Dissertations

With an increasing demand to reduce greenhouse gas (GHG) emissions, the conventional powertrain technology is at a saturation point. There is reinvigorated research interest in alternative powertrain designs that offer potentially higher efficiencies and lower engine-out emissions compared to conventional powertrains. The opposed piston two-stroke (OP2S) engine is one such alternative engine architecture that has demonstrated a reduction in engine-out emissions and increased efficiency compared to conventional four-stroke diesel engines. Like any two-stroke engine, the scavenging process and the composition of the internal residuals are predominantly governed by the pressure differential between the intake and the exhaust ports. Without dedicated …

Towards Trustworthy Federated Learning, Alina Basharat

Theses and Dissertations

Federated learning is a collaborative training model in which multiple clients optimize aglobal model by transmitting updates to a coordinating server while keeping raw data on-device, thereby reducing direct data exposure and enabling iterative global improvement. However, the iterative communication process is vulnerable to malicious attackers that either deliberately destroy the model or curious to infer raw data. Moreover, learning from multiple agents may result in unfair results. To enhance trustworthiness within this setting, we employ two-sided norm-based screening (TNBS) that removes both abnormally large and abnormally small updates, pair it with a q-fair objective to emphasize high-loss (disadvantaged) clients, …

When Textures Trim Drag: Micro-Structures For Adaptive Drag Reduction And Flow Authority, Miguel Angel Olvera

Theses and Dissertations

Turbulent boundary layers are a major source of drag and performance loss. This thesis investigates Triangular Porous Texturing (TPT), apex-forward microstructures with optional bleed channels, as a passive concept for simultaneously reducing skin friction and strengthening boundary layer momentum near separation. Low-speed wind tunnel tests are conducted over tripped turbulent boundary layers on flat plates with three surfaces: a smooth baseline, a solid-crest TPT array isolating the knife-edge “slip-cut” effect, and a porous-bleed TPT array whose paired micro-channels vent a small fraction of the free stream. Time-resolved PIV provides wall-normal velocity fields; skin friction is inferred from near-wall shear, and …

Modeling Flood Risks For Small-Scale Coastal Watershed Across Shared Socioeconomic Pathway Scenarios, Sebastian Loschner

Graduate Theses and Dissertations (2019 - present)

Coastal flooding, driven by the mixture of natural processes and human activities such as precipitation, waves, sea level rise, and urbanization, remains a growing concern. While recent flood-risk studies use IPCC's Shared Socioeconomic Pathways with climate projections to assess future flood exposure, smaller coastal watersheds, < 120,000 acres, remain insufficiently studied. Projected sea level rise is expected to intensify these impacts in smaller systems, potentially causing more severe flooding than reported for larger watersheds. To address this gap, this study used the SRH-2D model integrated with Aquaveo's Surface-water Modeling System to simulate flooding in the lower Fish River basin, Alabama. A coastal watershed sensitive to both riverine and tidal influences. Simulations tested different sea levels based on SSP scenarios corresponding to low, moderate, and high emissions for the years 2050 and 2100. Results indicate that the midcentury scenarios remained even in inundation extent and volume, between 9.9-10.4% compared to the 2020 baseline, the latter scenarios had a wider range in results of between 25.9-50.3% compared to the same baseline. Across scenarios, the most vulnerable and inundated areas of the smaller coastal watershed were the narrow points where upstream flow convene with downstream backwater. These findings highlight the need for futuristic location-specific flood mitigation strategies.

Learning To Accelerate Tightening Of Convex Relaxations Of The Ac Optimal Power Flow Problem, Faith Cengil, Harsha Nagarajan, Russell Bent, Sandra Eksioglu, Burak Eksioglu

Industrial Engineering Faculty Publications and Presentations

We propose a novel machine learning (ML)-based approach to significantly reduce the run times of the optimality-based bound tightening (OBBT) algorithm for strengthening the convex relaxations of the non-convex Alternating Current Optimal Power Flow (AC-OPF) problem. While OBBT can yield near-global solutions via tight convex relaxations, its runtime remains a critical bottleneck on large-scale power grids. Our key contribution is a dynamic policy that selects smaller subsets of voltage magnitude and phase-angle difference variables for sequential bound tightening at every iteration of the OBBT algorithm. This ensures that the bound-tightening process remains adaptive, thereby circumventing the stalling in the optimality …

Experimental Measurement Demonstration Of Initial And Steady-State Heights Of A Co2 Vertical Jet Fountain In Still Air, Brock Mcrae

Chemical Engineering Undergraduate Honors Theses

Atmospheric releases of heavier-than-air gases pose acute near-field hazards in low wind, yet the near-source behavior of vertical dense-gas jets in still air is sparsely documented. This thesis demonstrates a repeatable laboratory method for measuring the initial and steady-state rise heights of a carbon dioxide (CO₂) jet issued vertically from a floor nozzle in the CHRC ultra-low-speed wind tunnel under still-air conditions. Controlled mixtures (pure CO₂, 50/50 CO₂-air, 25/75 CO₂-air) were released at four flow rates (75, 100, 125, 150 LPM) with five repeats per condition. A fixed camera and tape-measure scale enabled video extraction of jet height using Kinovea …

Calibration And Validation Of Cyclic Stretching Platform For Stiffness Testing Of Engineered Heart Tissue, Jillian Welsh

Chemical Engineering Undergraduate Honors Theses

Cardiac fibrosis (CF) is a major contributor to the high mortality rate of heart failure which affects over 23 million people worldwide. CF involves cardiac fibroblasts depositing extracellular matrix, made primarily of collagen type I, which stiffens the heart walls over time. As testing new drugs for CF is deterred by the high cost and time required for animal and clinical trials, this research helps to solve the problem by providing an in vitro platform to study fibrosis.

The work involved creating tissues containing human cardiac fibroblast (HCFB) cells. Spring testing was conducted to determine the force applied by the …

Expanderizing Higher-Order Random Walks, Vedat Levi Alev, Shravas Rao

Computer Science Faculty Publications and Presentations

We study a variant of the down-up (also known as the Glauber dynamics) and up-down walks over an 𝑛-partite simplicial complex, which we call expanderized higher-order random walks—where the sequence of updated coordinates corresponds to the sequence of vertices visited by a random walk over an auxiliary expander graph 𝐻. When 𝐻 is the clique with self-loops on [𝑛], this random walk reduces to the usual down-up walk, and when 𝐻 is the directed cycle on [𝑛], this random walk reduces to the well-known systematic scan Glauber dynamics. We show that whenever the usual higher-order random walks satisfy a log-Sobolev …

Coupling Material Formulation Strategies To Tailor Piezoelectric Properties Of Ceramic Lattices, Amanda Lauren Borgaro

Open Access Theses & Dissertations

This thesis examines the material formulation and infiltration processes required to create interpenetrating ceramic composites with a particular focus on developing piezoelectric ceramic-epoxy lattice structures (PCELS). Following this, a high–solid loading barium titanite photopolymer resin (BT40) was developed to produce BTO scaffolds with controlled porosity suitable for metal infusion. The resin’s shear-thinning behavior and scattering-dominated curing response enabled the formation of stable, uniform ceramic structures whose pore networks directly influence infiltration behavior. Building on this foundation, a low-temperature Field’s Metal (FM) infiltration method was established using controlled thermal equilibration and the melting of pre-formed alloy rods. By maintaining the ceramic …

Computational Methods For Complex Electromagnetic Geometries And Media, Edgar Bustamante

Open Access Theses & Dissertations

Additive manufacturing has enabled electromagnetic devices with increasingly complex geometries, but existing numerical tools remain limited in their ability to model and design such structures. This dissertation presents two major advancements that address these restrictions in the finite-difference frequency-domain method (FDFD) and the spatially-variant lattice algorithm (SVLA). These two numerical methods provide a foundation for future exploration in the simulation, optimization, and realization of next-generation electromagnetic devices. First, a general bianisotropic FDFD formulation based on the vector wave equation is presented that enables practical modeling of metamaterials using effective medium homogenized parameters rather than explicitly resolving subwavelength metamaterial features. The …