Engineering Commons^™

Flight System Development For A Bio-Inspired Rotating Empennage Experimental Unmanned Aerial Vehicle, Ashton Gilbert

All Graduate Theses and Dissertations, Fall 2023 to Present

Unmanned aerial systems, commonly known as drones, are increasingly used for research, environmental monitoring, and testing new aircraft concepts. Many commercially available drone flight controllers work well for standard aircraft designs, but they can be difficult to adapt for experimental vehicles that use unconventional control methods or require detailed monitoring during testing. This creates challenges for researchers who need flexible and reliable tools to safely evaluate new flight technologies. This work presents the development of a custom drone flight control system designed specifically for experimental research. The system integrates custom electronics and software that allow researchers to easily modify control …

Psychometric Evaluation And Cognitive Correlates Of The Tactile Mental Cutting Test: Investigating Reliability, Validity, Gender Differences In Spatial Ability, Executive Function And Social Emotional Competence Among Native American Elementary Students, Sujata Basnet

All Graduate Theses and Dissertations, Fall 2023 to Present

Spatial ability-the ability to understand, visualize, and mentally manipulate shapes and objects-is important for learning in science, technology, engineering, and mathematics (STEM). However, many traditional spatial ability tests rely heavily on drawings and other visual representations and have often been developed and evaluated with populations that do not adequately represent culturally diverse students. As a result, there is a need for assessment approaches that are developmentally appropriate, engaging, and potentially more inclusive for young learners. The Tactile Mental Cutting Test (TMCT) provides one such approach by allowing students to explore three-dimensional objects through touch and physical manipulation while solving spatial …

Nanofluid-Assisted Enhanced Sealing Containment Of Caprocks For Efficient Geological Co2 Storage, Muhammad Ali, Nurudeen Yekeen, Mujahid Ali, Nilanjan Pal, Mohammed Al Kobaisi, Alireza Keshavarz, Hussein Hoteit

Research outputs 2022 to 2026

Millions of tons of CO2 are stored annually in geological formations in order to reduce greenhouse gas emissions, relying on caprock as a seal to prevent CO2 leakage. The wettability of caprock is crucial for its effectiveness, and can be altered by organic acids present in the storage media. The present study investigates the impact of stearic acid on the CO2 wettability of shale, along with the potential of alumina nanofluids to reverse this effect. Using contact angle measurements, X-ray diffraction, and other analytical methods, the study reveals that stearic acid increases the CO2 wettability of shale, making it more …

Extending Geometric Acoustic Ray Tracing To Multi-Room Environments: A Case Study On Gunshot Sound Transmission Between Adjacent Rooms, Tyler Ton

Theses and Dissertations

Accurate localization of gunshots in multi-room building environments remains a challenging problem in acoustic forensics and public safety applications. Existing approaches model sound propagation within a single room, neglecting the transmission of acoustic energy through walls and other building materials. This thesis presents a study on modeling multi-room gunshot acoustic transmission, combining geometric ray tracing with structural acoustic transmission-loss modeling to generate impulse responses for two horizontally adjacent rooms separated by a shared wall, providing a foundation for future inter-room gunshot localization work. The proposed system uses GSound-SIR, a geometric acoustics engine, to simulate sound propagation in both of the …

A Data-Driven Koopman Framework For Station-Keeping On Near Rectilinear Halo Orbit, Anusha Sharma Malladi

Theses and Dissertations

Cislunar missions have gained significant attention in recent decades, motivating the need for efficient modeling and reliable control. In this work a Koopman operator based framework is developed for approximating the error dynamics around a reference Near Rectilinear Halo Orbit (NRHO) in the Earth-Moon Circular Restricted Three-Body Problem (CR3BP). A decoder free neural network is used to learn a lifted linear representation of the nonlinear CR3BP dynamics and a residual based approach is used to identify the corresponding control input matrix. The model is then implemented in a receding-horizon target point controller and compared with uncontrolled propagation and a State …

Comparative Performance Of Physiological Vital-Sign Forecasting Under Random And Patient-Wise Splitting Using Deep Learning, Lavanya Vasavi Chittem Reddy

Theses and Dissertations

Physiological vital-sign forecasting estimates future measurements based on recent temporal patterns and can support analysis of continuously recorded monitoring data. This study comparatively evaluated deep feedforward, recurrent, bidirectional recurrent, long short-term memory, and bidirectional long short-term memory architectures for one-step-ahead forecasting of peripheral oxygen saturation, heart rate, and pulse rate. Each model received consecutive observations of peripheral oxygen saturation, heart rate, pulse rate, respiratory rate, and age, while separate single-output models predicted the next value of the selected target.

Random and patient-wise data splitting were compared using identical input definitions, preprocessing procedures, model architectures, and training hyperparameters. The strongest architecture …

Developing Imitation Learning Policies By Exploring Diffusion Framework For Quadcopters, Likith Swamireddy

Theses and Dissertations

Imitation learning offers a promising approach in developing near-optimal onboard policies for nonlinear systems, by learning from computationally expensive trajectory planners during offline training. Existing State-of-the-art methods commonly learn deterministic mappings from observations to actions by training fast neural networks to mimic the expert demonstrations, which can limit their ability to capture the action distribution, when the policy is trained on multiple possible expert commands to reach the same target, and this may lead to unsafe scenarios in the obstacle environments. To address these challenges, this study explores Diffusion Models (DMs) as a feedback controller for quadcopters that learns the …

Green Waste Biochar And Plant Growth-Promoting Bacteria Enhance Tomato Growth Under Combined Nutrient Deficiency And Salinity Stress, Soumaya Tounsi-Hammami, Munawwar Ali Khan, Mahra Alqemzi, Salama Ali Almehairi, Aneesa Rasheed Anwar

All Works

This study characterized a green-waste-derived biochar from date palms and ghaf trees and investigated its potential as a soil amendment with halotolerant Bacillus spp. to improve tomato seedling quality under dual stress of salinity and nutrient deficiency. Biochar was produced through pyrolysis at 450 °C and then characterized for yield, pH, electrical conductivity, proximate analysis, surface morphology, energy-dispersive X-ray spectroscopy, and heavy-metal content. Its effectiveness was tested both alone and in combination with a Bacillus sp. mix, using a completely randomized design with varying NPK fertilizer levels and saline irrigation. Tomato seedlings were evaluated 45 days after planting for various …

Reimagining Sustainable Sulfur Concrete: A Systematic Review Of Sulfur, Waste Integration, And Durability, Vasilia Al Khaldi, Abdel Hamid I. Mourad, Maisa Elgamal

All Works

Sulfur concrete (SC) - a thermoplastic, waterless composite in which molten sulfur-based binder replaces Portland cement - is attracting growing research attention as a sustainable construction alternative capable of superior performance in chemically aggressive environments. This systematic literature review synthesises evidence from 127 sources (2000–2025), examining three interlinked dimensions: (i) the role of waste and industrial by-product materials as aggregate and filler substitutes; (ii) the influence of aggregate type, morphology, and grading on mechanical and microstructural performance; and (iii) durability under acid, saline, and freeze-thaw exposures. A transparent, PRISMA-aligned screening and classification protocol - here used as a structured review …

Scalable Quality Assessment Of Ground Motion Records Via Interpretable Deep Learning Architectures, Ali Montazeri Namin

All Graduate Theses and Dissertations, Fall 2023 to Present

Earthquake engineers rely on accurate recordings of ground shaking to design safe and resilient buildings. However, sorting through thousands of these recordings to find the reliable ones and throwing out those ruined by sensor errors or background noise is traditionally done by hand. Because modern seismic networks collect massive amounts of earthquake data every day, this manual checking process is much too slow. To fix this, researchers are turning to artificial intelligence to automatically check the quality of these recordings.

While artificial intelligence offers a fast solution, there are limitations. These computer models can become massive and expensive to run, …

Characterization Of Droplet Size And Their Distribution Using Low Operating Conditions In A Rotary Bell Cup Spray-Field Via Shadowgraph, Murad Ali Channa, Mehdi Khiadani, Yasir M. Al-Abdeli

Research outputs 2022 to 2026

This study characterises droplet size and distribution across axial (x/D) and radial (r/D) locations in the spray field of a rotary bell-cup atomizer under low operating conditions. Shadowgraph was used to measure droplet size and distribution at 16 dimensionless locations in both directions. Two low rotational-speed ranges, 3–3.5 krpm (case I) and 8–8.5 krpm (case II), were achieved using shaping-air of 30–100 L/min under turning-air of 50 and 60 L/min, respectively, at a constant flow rate of 0.5 L/min. The Sauter mean droplet diameter ranged from ∼ 45–98 µm in case I and narrowed to ∼ 45–85 µm in case …

Thermophysical Characteristics Evaluation Of Carbon And Metal Oxide-Based Hybrid Phase Change Materials For Thermal Energy Storage Applications, Utpol K. Paul, Md Shahriar Mohtasim, Md Golam Kibria, Barun K. Das

Research outputs 2022 to 2026

Phase change materials (PCM) have limited practical applications due to their low heat conductivity. The main goal of this work is to improve the thermophysical properties of PCM by adding different compositions of hybrid carbon and metal oxide-based nanoparticles for incorporation into hybrid photovoltaic/thermal solar systems to accommodate the built environment and thermal energy storage as a building envelope for thermal comfort. Three types of nanoparticles have been selected including Graphene, Al2O3, and ZnO and synthesized samples with the combinations of 0.5 wt% Al2O3 + 2 wt% ZnO, 0.75 wt% Al2O3 + 2 wt% ZnO, 1 wt% Al2O3 + 2 …

Aluminium Based Hydrotalcite Like Compounds For Direct Lithium Extraction: A Critical Review On Crystallography And Structure Selectivity Design, Amin Sarmadi, Yasaman Boroumand, Mohammad Mahdi A. Shirazi, Magdalena Wajrak, Shayan Abrishami, Matthew Myers, Muhammad Rizwan Azhar, Amir Razmjou

Research outputs 2022 to 2026

The accelerating demand for lithium is intensifying interest in direct lithium extraction (DLE) technologies that minimise the environmental footprint of conventional solar evaporation ponds. Among sorbent-based DLE concepts, aluminium based hydrotalcite like compounds (Al-HTlc), particularly lithium aluminium layered double hydroxide (LiAl-LDH), are considered the most mature sorbent options, offering facile lithium (Li+) recovery and high selectivity in highly saline chloride based solutions. Both properties arise from a distinct intercalation mechanism wherein Li+ and its counter-anions (e.g. Cl− or SO42−) are co-intercalated into the crystal structure upon brine exposure. Li+ selectivity arises partly from a steric match between Li+ (ionic radius …

Thermally-Driven Equiaxation Of Columnar Grains And Α″ Nanoparticles Enabling Isotropic Β-Ti Alloys With Strength–Ductility Synergy Manufactured By Laser Powder Bed Fusion, Lei Qin, Shengfeng Zhou, Jianbo Jin, Huan Yang, Kunmao Li, Cheng Deng, Yujie Yuan, Lai-Chang Zhang

Research outputs 2022 to 2026

The transient thermal cycling characteristics during laser powder bed fusion (LPBF) induce elemental segregation and columnar growth, resulting in significant mechanical anisotropy and strength–ductility trade-off in titanium alloys. In order to break through this bottleneck, this work proposes a strategy of inducing equiaxation of columnar grains through recrystallization and regulating the morphology of the α″ phase (from an acicular shape to nanoparticles) to synergistically optimize the uniformity, strength and ductility of LPBF-fabricated Ti-35Nb-5Cu-xMo (Ti355x, x = 0, 1, 2, 4 wt%) alloys. The results demonstrate that LPBF-fabricated Ti355x alloys display equiaxed/columnar microstructures with significant mechanical anisotropy and strength–ductility trade-off. After …

Harnessing Surface Chemistry: A Comprehensive Review On The Role Of Functional Groups In Antifouling Membrane Design, Mohadeseh Najafi, Javad Farahbakhsh, Roham Ghanbari, Masoumeh Zargar

Research outputs 2022 to 2026

Membrane fouling remains a major barrier to reliable and cost-effective water treatment, motivating surface engineering strategies that suppress foulant attachment while preserving permeability and selectivity. This review critically examines antifouling membrane design through a functional-group-centred framework, focusing on grafted monomers and polymer architectures that regulate interfacial hydration, charge, polarity, and steric interactions. Oxygen-, nitrogen-, sulfur-, phosphorus-containing, zwitterionic, and multifunctional chemistries are comparatively evaluated across organic fouling, biofouling, colloidal deposition, and scaling. The analysis demonstrates that antifouling performance is governed not only by functional group identity but also by grafting density, chain conformation and mobility, spatial uniformity, and anchoring stability. Oxygen-rich …

Natural Gas Hydrate Production And Co2 Storage Via Clathrate Hydrates: Challenges And Opportunities, Abdirahman Hassan Mohamed, Aliyu Adebayo Sulaimon, Haylay Tsegab, Bhajan Lal, Stefan Iglauer, Muhammad Ali

Research outputs 2022 to 2026

One of the most demanding environmental and economic challenges of this era is that of supplying the increasing global energy demand while reducing and neutralizing the CO2 footprint. In this regard, the provision of a secure and diversified energy supply and the sequestration of CO2 into geological formations are currently of great significance. However, the buoyant nature of CO2 under the temperature and pressure conditions of typical geological sites leads to the risk of CO2 leakage, and thus necessitates long-term monitoring. Therefore, the hydrate-based sequestration of CO2 beneath oceanic sediments has become a desirable alternative to conventional geologic sequestration in …

Robust Hybrid Tree-Based Machine Learning-Assisted Optimization Of Well Parameters To Reduce Asphaltene Precipitation Risk In Oil Fields, Malek Jalilian, Madani, Alireza Keshavarz, Stefan Iglauer, Abbas Khaksar Manshad, Amir H. Mohammadi

Research outputs 2022 to 2026

Asphaltene precipitation is a persistent flow-assurance issue in carbonate oil wells, leading to increased intervention frequency and production losses. This study utilizes multi-decade surveillance and operational data from a mature carbonate field (1983–2023) to train and optimize five tree-based models: Decision Tree, Random Forest, Extra Trees, Gradient-Boosting Decision Tree, and CatBoost, employing a Tree-Structured Parzen Estimator. These models, constrained by operational parameters, were integrated to identify optimal settings that can minimize the frequency of asphaltene precipitation and the subsequent cleanups. The novelty of this research lies in the direct integration of interpretable tree ensembles with an optimizer that adheres to …

Diffusion-Enhanced Gflownet For Solving Vehicle Routing Problems, Ni Zhang, Zhiqin Zhang, Ling Pan, Hoong Chuin Lau, Zhiguang Cao

Research Collection School Of Computing and Information Systems

Traditional neural solvers for solving vehicle routing problems (VRPs) often suffer from limited solution diversity, motivating the development of Generative Flow Network (GFlowNet)–based models. However, the effectiveness of these models is frequently constrained by insufficient flow expansion in high-reward regions, limiting their ability to distribute probability across promising solution routes. The deeper exploration could yield superior results. Diffusion models, in contrast, provide stronger structural guidance for exploration. These two paradigms are naturally complementary: GFlowNet can supply edge-level signals for diffusion to embed, while diffusion can guide broader exploration. Leveraging this synergy, we propose Diffusion-Enhanced GFlowNet (DEG), a novel framework that …

Switching Configurations For Reconfigurable Battery Packs: A Review, Kenneth Tetteh Akiti, Quoc Viet Phung, Iftekhar Ahmad, Daryoush Habibi

Research outputs 2022 to 2026

Conventional Battery Energy Storage Systems (BESS) are designed with fixed cell topologies, where the electrical connection between cells remains unchanged throughout their life. Although Battery Management Systems (BMS) and conventional cell-balancing techniques are employed to monitor and maintain performance, they often fail to address key challenges such as uneven cell aging, capacity mismatch, and fault isolation that arise especially during the second life of a battery pack. These limitations can result in reduced efficiency, reduced reliability, and shortened battery life. As large-scale battery packs become increasingly common in Electric Vehicles (EVs), smart grids, robotics, and renewable energy systems, the limitations …

Annual Conference 2024 Workshop Report, Rahat Ullah, Adhban Farea, Joe Harrington, Ted Mc Kenna

Reports

This report presents the findings from industry workshops held during the Build Digital Annual Conference on 17 October 2024 in Cork.

The workshops brought together stakeholders from national infrastructure, local authority infrastructure and housing to discuss challenges, priorities and opportunities associated with digital transformation in the Irish construction sector.

The report identifies common themes including leadership and organisational support, digital skills and training, information exchange, resource allocation and the management of asset information.

The findings provide insights into the practical supports required to advance digital adoption across public sector organisations.

Structural And Electrochemical Characterization Of Na2co3/ Γ- Al2o3 Electrodes For Supercapacitor, Wiwin Dwiana, Jeniva Dinta Nanda Fahreza, Anissa Chairani Alfin Nadhira, Fatimatuz Zahra, Erma Surya Yuliana, Muhammad Safwan Abd Aziz, Nandang Mufti

Journal of Mechanical Engineering Science and Technology (JMEST)

The development of electrode materials with suitable structural and surface properties is crucial for improving electrochemical energy storage systems. Gamma alumina (𝛾-Al₂O₃) has attracted considerable interest in electrochemical research due to its unique structural and surface properties. However, its charge-storage capacity is still limited, highlighting the need for structural and compositional modifications to improve its electrochemical performance. In this study, Na₂CO₃ was introduced into 𝛾-Al₂O₃ as a sodium precursor to induce phase modification and enhance the electrochemical activity. The systematic incorporation of Na₂CO₃ also provides an opportunity …

A Systematic Review Of Alkali-Treated Polylactic Acid Biocomposites Relevant To Pineapple Leaf And Water Hyacinth Hybrid Design, Muhammad Rizky Adrianto Subandi, Tri Hartutuk Ningsih, Hanna Zakiyya

Journal of Mechanical Engineering Science and Technology (JMEST)

The increasing demand for sustainable materials has accelerated the development of biodegradable polymer composites. Polylactic acid (PLA)-based natural fiber composites have attracted significant attention due to their renewable characteristics; however, their performance remains limited by weak fiber–matrix compatibility, moisture sensitivity, and inconsistent interfacial behavior. Alkali treatment has been widely applied to modify lignocellulosic fibers by removing non-cellulosic components and improving surface characteristics, although its effectiveness remains dependent on treatment conditions and fiber properties. This systematic review evaluates the influence of alkali treatment on PLA-based natural fiber composites and assesses the available evidence supporting future pineapple leaf fiber (PALF) and water …

Effect Of Preheating Palm Oil Biodiesel Fuel On The Performance And Emissions Of Diesel Engine Common Rail Direct Injection, Nanang Romandoni, Achmad Aminudin, Hari Setiapraja, Bima Randi Wardiasaputra, Kelvin Dwi Wardana, Ahmad Yusril Aminullah, Deni Nur Fauzi, Kholis Nur Faizin, Nur Ihda Farikhatin Nisa

Journal of Mechanical Engineering Science and Technology (JMEST)

Fossil fuel consumption continues to increase while its reserves continue to decrease and produce high emissions that trigger global warming. Therefore, more environmentally friendly alternative energy is needed. Biodiesel is a sustainable choice because it is biodegradable, low in sulphur, and can replace fossil fuels. This study investigates the influence of biodiesel fuel preheating temperature on engine performance, fuel consumption, and emissions in a Common Rail Direct Injection (CRDI) diesel engine. The experimental method was carried out by heating B40 and B50 fuels at temperatures of 40°C to 60°C at intervals of 10 °C. Engine performance was evaluated using a …

Engineers Without Borders Lunch & Learn Presentation, Brian Roth, Ruben Yoder, Phoenix Professional Chapter

International Education Week

Discover how engineering can help address challenges and improve lives around the world. Learn from Engineers Without Borders students and professionals about their global work, community partnerships, and opportunities to get involved.

Ncf Sensor Coated With Cofe1.96la0.04o4/Lafeo3 Heterostructures For Room-Temperature Detection Of Liquefied Petroleum Gas Concentration, Ziqiang Liu, Fujian Tang, Yufang He, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Liquefied petroleum gas (LPG) is a highly flammable fuel widely used for cooking, heating and transportation, making real-time leak detection essential for preventing fire, explosion, and suffocation hazards. In this study, a room-temperature no-core fiber (NCF) sensor coated with CoFe_1.96La_0.04O₄/LaFeO₃ heterostructures was developed for LPG detection. The heterostructures were characterized using XRD, Raman spectroscopy, SEM, TEM, XPS, PL spectroscopy, and UV–vis spectroscopy. Experimental results showed that La incorporation and heterostructure formation refined the particles size, improved surface accessibility, and modulated the electronic structure and band gap, thereby enhancing LPG adsorption, carrier redistribution, and …

Lithium Titanate-Functionalized Mixed Matrix Polymer Membrane For High-Performance Osmotic Energy Conversion, Rockson Kwesi Tonnah, Yasaman Boroumand, Milad Razbin, Mostafa Vahdani, Amir Razmjou, Mohsen Asadnia

Research outputs 2022 to 2026

Reverse electrodialysis (RED) offers a promising route to harvest osmotic energy from salinity gradients, yet practical implementation is hindered by the lack of scalable, high-performance ion-selective membranes that combine efficient ion transport with mechanical robustness and environmental sustainability. Here, we report a mixed matrix membrane composed of polyethersulfone (PES), polyvinylpyrrolidone (PVP), and lithium titanium oxide (Li₂TiO₃, LTO) that addresses these challenges through biomimetic ion transport channels. The strategic integration of LTO nanoparticles introduces ion-exchange sites and oxygen-rich PES ether linkages to create preferential cation transport pathways that mimic biological ion channels. This mixed matrix design delivers over three-fold cation conduction, …

A Built Environment Framework For Sustainable Urban Transport In Developing Countries: Lessons From Copenhagen, Nassamat Mahdy Mohamed, Mohamed Anwer Zayed, Ingy Mohamed El Barmelgy

HBRC Journal

Developing countries are suffering from several urban transport challenges. In addition, global strategies of sustainable urban transport (SUT) lack integration with the seven dimensions of the built environment (7Ds). Therefore, there is a gap between the global strategies and their practical application, especially in the developing countries. To address this gap, this study aims to propose built environment framework for SUT in developing countries. This is addressed by analyzing a selection of global urban transport strategies and extracting consolidated applicable principles, then analyzing Copenhagen as a leading case study in SUT. Based on the research foundation and literature review, the …

Experimental And Cfd Analysis Of Heat Generation During Fly Ash Carbonation From Fbc Boiler, Tomasz Janoszek

Journal of Sustainable Mining

The transition toward a closed-loop economy and improved energy efficiency in the industrial sector has highlighted the importance of waste heat recovery and carbon dioxide (CO₂) sequestration. This study investigates the carbonation of fly ash derived from fluidized bed boilers as a method for stabilizing reactive calcium oxide (CaO) while recovering the exothermic heat released during the process. Fly ash carbonation involves reactions between free CaO, CO₂, and water, forming stable calcium carbonate (CaCO₃) and generating significant thermal energy. Laboratory experiments were conducted in an adiabatic rotary reactor equipped with seven thermocouples to monitor the temperature profile of the carbonating …

Forecast Of Mining Fatalities Using Machine Learning Algorithms, Enoch Nii-Okai

Journal of Sustainable Mining

The mining industry plays a crucial role in economic development, but is often accompanied by notable occupational hazards, including fatalities. This research investigates the application of machine learning techniques to predict mining fatalities in the United States using historical data from 1983 to 2023, sourced from the National Institute for Occupational Safety and Health (NIOSH) and FRED Economic Data. Predictive models, including random forest (RF), gradient boosting (GB), decision tree (DT), multiple linear regression (MLR), and linear regression (LR), were employed to assess relationships between operational parameters and annual fatality counts. The dataset was thoroughly preprocessed, addressing missing values and …

Effect Of Cryogenic Soaking Duration On The Crystallographic Structure And Corrosion Resistance Of Astm A36 Steel, Sukri Mubarok, Andoko Andoko, Retno Wulandari

Journal of Mechanical Engineering Science and Technology (JMEST)

This study investigates the influence of cryogenic soaking duration on the crystallographic characteristics and corrosion resistance of ASTM A36 structural steel. Specimens were immersed in liquid nitrogen at −196°C for 0, 12, 36, and 60 hours. Crystallographic analysis was conducted using X-ray diffraction (XRD), while electrochemical corrosion behavior was assessed through Tafel polarization in 3.5% NaCl solution using an Autolab PGstat. Key parameters evaluated included crystallite size, microstrain, dislocation density, corrosion rate, and material degradation. The results showed that soaking up to 36 hours significantly refined the microstructure, as indicated by reduced crystallite size and increased dislocation density and microstrain. …