Engineering Commons^™

Role Of Directional Conditional Filtering On Droplet Velocity And Size Distribution, Farzad Hossain, Matthew J. Cleary, Yasir M. Al-Abdeli, Mehdi Khiadani

Research outputs 2022 to 2026

This study investigates the role of directional filtering in the analysis of spray behaviour using two full cone nozzles (65° and 75°) emitting aqueous sprays under atmospheric conditions. A hybrid computational–experimental framework was applied, using Large Eddy Simulation (LES) with Discrete Phase Model (DPM) and Rosin-Rammler distribution in ANSYS Fluent, validated against Shadowgraph and Particle Image Velocimetry (PIV) measurements. The sensitivity of directional filtering to the effects of spray angle and flow rate (1.75 and 3.5 L/min), were also done. Upward-filtered droplets consistently exhibited greater breakup than both raw and downward-filtered data due to gravitational opposition and longer air exposure. …

Comparative Fatigue Analysis Of Cf-Pla Metamaterial Bone Plates For Orthopaedic Fixation, Ani Daniel, Hamed Bakhtiari, Barun K. Das, Muhammad Aamir, Majid Tolouei-Rad

Research outputs 2022 to 2026

Bone plates are widely used in orthopaedic surgery to stabilise fractured bones and support healing following traumatic injuries or osteotomies. However, conventional metallic bone plates suffer from stress shielding and stiffness mismatch with bone, which can hinder optimal healing. Additive manufacturing enables the incorporation of novel metamaterial architectures into polymer-based implants to enhance mechanical properties. The fatigue behaviour of these implants during the healing period is critical to ensuring their structural integrity and long-term performance. In this study, the compressive fatigue performance of fused deposition modelling (FDM)-printed carbon fibre-reinforced polylactic acid (CF-PLA) bone plates were investigated. Four metamaterial structures—tetrachiral, re-entrant, …

Thermo-Hydro-Chemical Coupled Numerical Modeling Of Hydrogen-Thermal Co-Development In Hydraulically Fractured Peridotite, Jiacheng Dai, Zhonglin Ma, Yunzhi Yue, Yujie Yuan, Shouceng Tian

Research outputs 2022 to 2026

Hydrogen generation through serpentinization reactions in peridotite formations under high temperature conditions represents a promising avenue for subsurface hydrogen production. However, the thermal energy in the formation environment have not been sufficiently considered. To integrate hydrogen production with thermal energy development, this study develops a thermo-hydro-chemical coupled numerical model, which is used to investigate hydrogen-thermal co-development in hydraulically fractured peridotite. Given that the hydrogen-thermal co-development process involves fluid flow, heat transfer and serpentinization reactions, the governing equations are formulated based on Darcy flow and energy conservation equations, with serpentinization kinetics incorporated through the reactive source terms. To evaluate hydrogen production …

Application Of Maritime Non-Line-Of-Sight Relay Attack On Wireless Digital Communication, Nathan Meyer

School of Computing: Dissertations, Theses, and Student Research

As wireless communication becomes increasingly prevalent, securing information over wireless channels is an ongoing challenge, especially in maritime environments where communication depends on radio links. While higher layer wireless attacks have been widely studied, lower level physical-layer relay attacks in maritime settings have received less attention. This thesis presents a simulation of a maritime relay attack in a beyond line-of-sight wireless environment for study. A three antenna communication model is developed where a legitimate transmitter sends a digital wireless signal, an attacking antenna intercepts, modifies, and retransmits the signal, and a final receiver observes both the direct and relay transmission. …

A Webcam Eye Tracking Infrastructure For Software Engineering Tasks, Zachary M. Kozak

School of Computing: Dissertations, Theses, and Student Research

Performing eye tracking utilizing commodity webcams has been explored for over a decade, but limited camera quality and sensitivity to head movements have hindered its adoption in research settings. Recent advances in consumer-grade webcams and machine learning methods present an opportunity to improve the accuracy of webcam eye tracking and extend the feasibility of studies beyond controlled laboratory environments.

Current popular webcam eye tracking methods restrict implementations to the browser and rely on continuous user interactions for calibration, limiting the kinds of studies that can be conducted. This thesis presents a feature-based gaze prediction system that incorporates eye geometry and …

Leveraging Code Embeddings To Identify And Address Blind Spots In Benchmark Creation, Charles Moloney

School of Computing: Dissertations, Theses, and Student Research

Formal software verification remains critical for early vulnerability detection, yet benchmarking these tools is costly and often reliant on centralized datasets such as SV-COMP. While such repositories enable standardized evaluation, they introduce risks of overfitting and bias, particularly due to first-party benchmark contributions. To address these limitations, we extend ARG-V, our tool for generating SV-COMP-compatible benchmarks from real-world Java code, with a novel approach of using code embedding techniques to selectively sample from mined code. By leveraging Nomic Embed Code and a cosine-based Minimum Hyperspherical Energy (MHE) objective, we systematically select and transform benchmarks from scraped GitHub code that …

Design And Development Of A Passive Dust Protection System For Lunar Docking Operations, Simon Thengvall

Department of Mechanical and Materials Engineering: Dissertations, Theses, and Student Research

Lunar docking systems face a unique set of environmental conditions that can create significant challenges for mechanical design. Among these, the abrasive nature of lunar regolith can impair the kinematic function of traditional terrestrial mechanisms as well as contaminate critical spacecraft components such as environmental seals, causing them to fail. For crew-rated docking systems, failure of these systems not only threatens mission success, but also crew safety, so dust protection is crucial for docking components. To address the concerns of regolith intrusion, the Simple External Attachment for Lunar Openings (SEALO) is developed as a key architecture for mechanism evaluation when …

Cylindrical Versus Spherical Self-Similar Capillary Cavity Collapse, Karl Cardin, Christophe Josserand, Raul Bayoan Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Drop tower experiments have been performed to study the capillary collapse of large high-aspect-ratio cavities. Cavities are formed by momentarily impinging the free surface of a liquid bath with a jet of air in the microgravity environment of a drop tower. The collapse may give rise to a jet and three distinct jetting regimes are identified. Simulations are performed to further investigate the phenomena. The abrupt emergence of a thin high velocity jet is observed experimentally and numerically at a specific initial cavity aspect ratio. Different power laws are identified in different regions of the cavity during the collapse providing …

Optimized Bombax Ceiba/Jute Hybrid Epoxy Composites For Enhanced Thermal Insulation Performance, Shadman Ahmed Khan, Naeem Ahmmed, Md Tanvir Hossain, Abdullah Ibn Asheque, Md Ariful Islam, Md Abdul Kader, Md Sohel Rana, Sakib Masud

Michigan Tech Publications

The development of sustainable hybrid natural-fiber composites provides a practical way toward lightweight materials with tailored mechanical and thermal performance. In this study, Bombax ceiba (BC)/jute hybrid epoxy composites were fabricated using a stacked preform followed by compression molding, and the effect of fiber blending ratio on mechanical, thermal, and microstructural properties was systematically investigated. Three compositions-40/60, 50/50, and 60/40 BC/jute by weight-were evaluated. Mechanical testing showed that the J50 composite, with a balanced fiber ratio, exhibited superior flexural strength and impact resistance, indicating effective hybrid synergy and improved stress transfer between fibers and the matrix. Thermogravimetric analysis showed that …

Quantitative Study Of The Predictive Correlational Relationship Between Passenger Knowledge, Attitudes, And Behaviors In Aviation Ground Safety Events, Nikkolas Howard Kraay

Doctoral Dissertations and Projects

This study examined the relationships between passenger cabin safety knowledge, attitude, and behavior using the Knowledge-Attitude-Behavior (KAB) framework as the guiding theoretical model. Although prior aviation safety research has demonstrated a linear progression from knowledge to attitudes to behaviors, these studies were conducted primarily in Asian cultural contexts. The present study investigated whether this linear sequence would hold within a larger cultural passenger population. A predictive correlational design was used, and data was collected through an online survey completed by 194 adult airline passengers. The instrument measured cabin safety knowledge, attitudes, and behavioral intent, along with demographic characteristics.

Data was …

Problems With Small Drinking Water Systems In Developing And Developed Countries: How Do They Compare?, Kurt Kesteloot

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation compares the factors that drive the long-term functionality of small drinking water systems (serving fewer than 10,000 people) in developing and developed country contexts, with a focus on groundwater supplies. Using regression analysis in SAS and complementary fuzzy-set Qualitative Comparative Analysis (fsQCA) for developing countries, the study integrates two datasets: 23 Engineers Without Borders project surveys (90+ variables across 14 countries) and a multi-year National Park Service inspection dataset (approximately 1,561 systems; 7,460 recorded deficiencies, enriched with U.S. Census ZIP-code aggregates). In developing countries, statistically significant predictors of success include government cash contributions (odds ratio [OR] ≈ 67.6), …

Electrospun Pan-Derived Carbon Nanofibers Embedded With Nicofew-Based High-Entropy Oxides For Electrocatalytic Oxygen Evolution Reaction, Alireza Noroozi, Mahdavi, M. Baris Yagci, Mohammad Mahdi A. Shirazi, Saeed Bazgir, Hadi Jahangiri, Uğur Ünal

Research outputs 2022 to 2026

High-entropy oxides composed of Ni, Co, Fe, W, and a fifth transition element (Mo, Mn, or Cu) were integrated into electrospun polyacrylonitrile nanofibers to form porous nitrogen-doped carbon membranes for the oxygen evolution reaction. Gas-assisted electrospinning enabled uniform dispersion of high-entropy oxide nanoparticles within the polyacrylonitrile matrix, while calcination at 800°C produced conductive carbon frameworks embedding crystalline high-entropy oxides with homogeneous elemental distribution. Structural and surface analyses confirmed the preservation of high-entropy oxide phases, catalytic graphitization of the carbon matrix, and strong interfacial bonding between metal oxides and carbon. Among all compositions, Mo-HEO@NC exhibited the lowest overpotential (≈240 mV at …

Wavetable Modification In Frequency Domain: Fourier Analysis With Matlab Implementation, Caleb Kortens

Senior Honors Theses

One of the challenges in creating computer generated music is producing life-like sounds. Music produced through computer synthesis can often sound thin and synthetic rather than vibrant and energetic. Wavetable synthesis is a method of waveform generation that uses a wavetable, which is a set of single period waves, or frames, that have varying characteristics. This method allows a synthesizer to transition between waveforms to produce a sound with time varying tone and harmonic characteristics. This adds life and movement to computer generated sounds. Wavetable synthesis is often used to imitate actual instruments, but unique wavetables can be created that …

Dynamic Cushioning Performance And Sustainability Implications Of Recycled-Content Expanded Polyethylene Foams, Jay Singh, Pratish Patel, Emily Recinos, Paulina Goncharov

Industrial Technology and Packaging

The transition toward circular materials in protective packaging requires empirical evidence that recycled-content foams can satisfy stringent shock-attenuation requirements. This study evaluates the dynamic cushioning performance of expanded polyethylene (EPE) foams formulated with 0%, 30% and 40% recycled content under controlled impact conditions following ASTM D1596. A total of 1100 drop tests were conducted across combinations of density, thickness, static load and drop height representative of distribution hazards in parcel and freight supply chains. Peak transmitted acceleration (G) was measured as the primary performance response variable.

Across the configurations evaluated, recycled-content EPE foams exhibited cushioning performance comparable to virgin materials. …

Quantifying Evapotranspiration From The Wetlands In The Peripheral Area Between The Most Downstream Stream Gages And The Open Water Body Of The Great Salt Lake, Motasem S. Abualqumboz, David G. Tarboton

Publications

Study region: The eastern peripheral area between the most downstream stream gages and the open water body of the Great Salt Lake (GSL), located in northern Utah within the semiarid western United States (US). 

Study focus: As GSL levels decline, the eastern peripheral area is expanding, exposing former lakebed, much of which has transitioned into natural and managed wetlands. Evapotranspiration (ET) from these wetlands consumes water that would otherwise reach the open-water lake body, yet these losses remain poorly quantified and directly affect the GSL water balance. This study compares a water-balance-based ET estimate for the wetlands in the peripheral …

Water Velocity And Discharge From Tidal Freshwater Creeks In Forested And Herbaceous Wetlands, Austin S. Hudson, G. Curtis Roegner, Gary E. Johnson, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

Acoustic Doppler Current Profilers were deployed in four tidal creeks within forested swamps and herbaceous marshes in the lower Columbia River. Measurements were collected over 12 to 20-day periods during high and low river stage, and then analyzed using wavelet tidal analysis software (CWT_Multi) to characterize temporal variability of water elevation, velocity, and discharge. While subject to similar fluvial and tidal forcing, nuances in creek geometry led to large differences in their hydraulic response. Most obviously, creeks in the higher elevation forested swamps were hydraulically isolated, which limited subtidal discharge but increased tidal monthly variability of discharge in comparison to …

Open Multi-Agent Systems: The Free-Range-Zoo Framework And Moasei Competition, Ceferino J. Patino Iv

School of Computing: Dissertations, Theses, and Student Research

The field of multi-agent reinforcement learning (MARL) has made significant strides in addressing sequential decision-making problems under uncertainty. However, traditional MARL frameworks assume closed-world settings with fixed agent sets, static task distributions, and unchanging environment dynamics. This thesis presents two complementary contributions that advance the state of open-world multi-agent systems research: (1) the free-range-zoo framework, an open-source environment suite for MARL in open environments featuring dynamic agent populations, evolving task sets, and changing operational frames; and (2) the MOASEI Competition, an international benchmarking event that leverages free-range-zoo to evaluate how artificial agents handle openness in complex, partially observable domains. The …

External Force Control Of Transitional And Turbulent Flows, Cesar Alberto Leos

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

Turbulence in wall-bounded flows governs momentum transport, drag, and energy efficiency in a wide range of engineering systems, yet its response to external forcing remains incompletely understood across transitional and high Reynolds number regimes. This dissertation investigates an active flow control strategy based on spanwise external forcing and demonstrates how it modifies the dynamics of transitional and turbulent channel flows with the objective of identifying the mechanisms through which forcing alters transition, flow physics, and turbulent drag reduction.

Firstly, direct numerical simulations are performed to examine the subcritical transition under external forcing. The onset and sustenance of turbulence are shown …

A Machine Learning Framework For Ddos Attack Detection In Sdn-Enabled Mobile Wireless Networks, Ishita Sharma, Satyam Agarwai, Shashi Shekhar Jha, Sumit Chakravarty

Faculty Articles

Attacks on network components and devices pose a significant threat to service continuity, necessitating robust detection mechanisms. This paper presents a Distributed Denial of Service (DDoS) attack detection framework tailored for heterogeneous mobile wireless networks within a Software-Defined Networking architecture. A two-tier model is proposed: localized attack detection at access points (APs) using a Multi-Layer Perceptron (MLP) classifier, and centralized detection under mobility at the controller using a Long Short-Term Memory (LSTM) model. The system incorporates novel traffic features such as flow count, speed of source IP, source and destination IP address entropy, proportion of bidirectional flows, and handover frequency, …

Integrated Approaches For Valorization Of Chicken Feather Waste: From Extraction To Application Of Keratin-Based Bioproducts, Muhammad Ehtasham Akram

Dissertations and Doctoral Documents, University of Nebraska-Lincoln, 2023–

This dissertation explores the optimization of chicken feathers keratin hydrolysate (CFKH) production using alkaline hydrolysis (AH) and sub-critical water hydrolysis (SCWH), focusing on acquiring high keratin yield in the hydrolysate. Then, CFKH along with other locally sourced materials, was used to develop bioplastics with regenerative agriculture properties (BioWRAP), with the ultimate objective of applying it as a soil mulch to suppress weeds in agricultural crops. This work also addresses challenges in process design and industrial scale-up of BioWRAP. Chapter 1 is a literature review that introduces terms like biobased, biodegradable, and bioplastics, materials and methods used to make bioplastics, and …

Vacuum Modification Of The Surface Properties Of T15k6 Hard Alloy By Plasma–Chemical Synthesis Of Tin-Cu Coatings, Aleksandr Semenov, Dmitriy Tsyrenov, Nikolay Ulakhanov, Irina Semenova, Undrakh Mishigdorzhiyn, Wen Ma, Simon C. Tung, George E. Totten

Mechanical and Materials Engineering Faculty Publications and Presentations

The design and main parameters of a plasma–chemical reactor containing two compartments are presented. One compartment houses a vacuum-arc evaporator, while the other houses a planar magnetron. The compartments are separated by a diaphragm with a dosing slot for injecting copper vapor into the TiN synthesis compartment. The conditions for the synthesis of superhard TiN-Cu composite coatings are experimentally determined. Based on established process parameters for TiN synthesis in a nitrogen-containing plasma by Ti evaporation using a vacuum-arc discharge, it is proposed to apply TiN-Cu coatings by injecting Cu vapor into the TiN synthesis area and sputtering Cu using a …

Ai-Driven Detection Of Failure Modes In Thermoplastic Composites Using Acoustic Emission Techniques, M. M. Shahzamanian, Li Ai, Paul Ziehl

Civil Engineering Faculty Publications

Composite materials in aircraft structures can suffer impact damage that leaves barely visible yet structurally significant defects, which degrade mechanical performance, especially under compressive loads. Existing methods for identifying failure modes in compression after impact (CAI) tests using acoustic emission (AE) data are limited in accuracy and scope. This study introduces an approach combining AE sensing with a heterogeneous ensemble convolutional neural network (CNN) to detect and classify failure mechanisms in impacted composite specimens. The novelty of this work lies in employing Red, Green, and Blue (RGB) wavelet images, produced through continuous wavelet transform (CWT) of AE signals, as inputs …

A Machine Learning Framework For Ddos Attack Detection In Sdn-Enabled Mobile Wireless Networks, Ishita Sharma, Satyam Agarwal, Shashi Shekhar Jha, Sumit Chakravarty

Faculty Articles

Attacks on network components and devices pose a significant threat to service continuity, necessitating robust detection mechanisms. This paper presents a Distributed Denial of Service (DDoS) attack detection framework tailored for heterogeneous mobile wireless networks within a Software-Defined Networking architecture. A two-tier model is proposed: localized attack detection at access points (APs) using a Multi-Layer Perceptron (MLP) classifier, and centralized detection under mobility at the controller using a Long Short-Term Memory (LSTM) model. The system incorporates novel traffic features such as flow count, speed of source IP, source and destination IP address entropy, proportion of bidirectional flows, and handover frequency, …

An Evaluation Of Total Navicular Implants: A Scoping Review, James Mcclure Hughes, Nicholas Belardo Obias, Amanda Killeen

School of Podiatric Medicine - Student Research

The aim of this study is to determine the efficacy and safety profile of total navicular implants based on current literature.

Navicular insults such as high-energy trauma, osteonecrosis, and Muller-Weiss syndrome may result in avascular necrosis or a critical sized bone defect, conditions that are highly difficult to manage given current treatment modalities. Total navicular implants may offer a solution to these problems. While 3D printing of implants remains investigational, its use in highly individualized cases involving the talus has had promising results with conditions like avascular necrosis, tumors, trauma, and arthritis. The navicular is unique in its attachments to …

Ceres Cow Excrement For Renewable Energy Supplies, Jeremy J. Land

Chemistry and Chemical Engineering Student Publications

On March 27th, 2026, President Trump announced the finalization of the Renewable Fuel Standard “Set 2”, which establishes a 60% increase in the requirement for renewable fuels from 2025 to 2026 & 2027. AIChE issued the 2026 Senior Design Challenge to design a renewable natural gas plant for a 12-Farm Dairy Co-Op in Green Bay Wisconsin. This design integrates the latest cutting-edge technologies to sustainably optimize NPV.

Slait - Secure Language Assembly Inspector Tool, Michael Bratcher, Maria Linkins-Nielsen

Electrical Engineering and Computer Science Student Publications

Develop a secure web-based platform that enables users to:

• Upload assembly programs through a browser
• Select instruction inspection points
• Execute code inside an isolated sandbox
• Capture register and flag state changes
• Visualize execution behavior step-by-step

Breach Buddy: Compact Ugv, Zane Hicks, William Stanish, Kyle Gillenwater, Luis Garbanzos

Electrical Engineering and Computer Science Student Publications

This project addresses the challenges of obtaining real-time intelligence in hazardous environments, where personnel face significant risks and many existing systems face significant drawbacks.

Aurora Display - Autonomous Dashboard For Smart Spaces, Isabella Bretthauer, Zach Collins

Electrical Engineering and Computer Science Student Publications

Aurora Display is a low-cost, API-driven digital signage platform for public environments. Built on Raspberry Pi 4B, it retrieves and normalizes real-time data from multiple sources and displays it through a modular tile interface. Local caching and fallback states ensure continuous, autonomous operation. A working prototype demonstrates adaptable deployment, sustainable operation, and continuous real-time, context-aware, information delivery.

Skin Cancer Detection App, Nicholas Rincon-Speranza, Lawson Darrow, Nikiraj Konwar, Christian Stevens

Electrical Engineering and Computer Science Student Publications

Skin cancer is one of the most common cancers, and early detection greatly improves outcomes.

Many people do not have quick or easy access to a dermatologist for an initial screening.

Our goal was to build a mobile app that can analyze a lesion image and provide a fast preliminary prediction on device.

This is not meant to replace a doctor, but to serve as an accessible screening aid that encourages earlier follow-up.

Diode-Pumped Solid-State (Dpss) Laser, Ryan Farrar, Kiahna Taylor, Jules Stone, Finn Mcmanus, Zoe Kreisler, Reis Knowles

Electrical Engineering and Computer Science Student Publications

The objective of this project is to create a working Nd:YAG laser design using an 808nm laser instead of a traditional flashlamp. The reason for the 808nm laser is to enable controlled lasing, and furthering accuracy & efficiency relative to a flashlamp.