Engineering Commons^™

New Insights Into Dynamic Evolution Of Colloidal Network Structure During Early-Age Hardening Of Cementitious Materials, Hengrui Liu, Kaiyin Zhao, Shipeng Zhang, Hanghua Zhang, Shuangshuang Liu, Lucen Hao, Hongyan Ma, Kamal Khayat, Chi Sun Poon

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The evolution of microstructure in cementitious materials during their transition from fluid to solid state plays a critical role in determining their ultimate mechanical strength and overall performance. This hydration stage primarily involves a dynamic densification process occurring within the colloidal network. However, the field of cement-based materials currently lacks a comprehensive theoretical framework and associated parameters capable of effectively characterizing the specific structural regions within this network. In this study, we propose an Improved Particle Linkage (IPL) theory for describing the strength, types, and quantities of particle linkages within colloidal network. The IPL theory classifies the internal network structure …

Design And Validation Of A Wearable Respiratory Protection System For Wildland Firefighters, Oliver Pilon

Master's Theses

Wildland and Wildland–Urban Interface firefighters are routinely exposed to hazardous smoke with fine particulate matter, carbon monoxide, volatile organic compounds, and other toxic combustion products. Existing protective gear has significant limitations and shortcomings for these conditions. Respirators with tight-fitting facepieces make it difficult to breathe and speak. On the other hand, self-contained breathing apparatuses are too heavy, have a limited duration of use, and do not work well with long wildland fire scenes, while smaller protective equipment like N-95’s and gaiters provide very little protection. These constraints contribute to low adoption rates and prolonged occupational exposure.

This thesis presents the …

Quantitative Comparison Of Different Ultrasound Simulation Approaches For Civil Engineering Applications, Fabian Dethof, Simon Schmid, Jean-Marie Henault, Thomas Schumacher, Sylvia Kessler, Salvador Villalobos

Civil and Environmental Engineering Faculty Publications and Presentations

Interpreting ultrasonic waveforms is often challenging, especially in the presence of tilted boundaries that introduce multiple reflections, mode conversions, and echoes. To analyze such complex signal patterns, wavefield simulations provide a valuable tool. To ensure confidence in the simulation results, the accuracy of the numerical method is crucial. Another consideration when using simulations is their computational expense. Especially in civil engineering applications, large structures need to be investigated, which may not be feasible given the available resources. In this study, different numerical methods and software implementations commonly used for simulations in civil engineering are compared, including the Elastodynamic Finite Integration …

A Borophosphate Glass Doped With Cobalt Oxide Improves Skeletal Muscle Structure And Function In Myopathic Mice, Jacob A. Kendra, Alexandra G. Naman, Rebekah L. Blatt, Carla D. Zingariello, Richard K. Brow, Steven S. Segal, Aaron B. Morton

Materials Science and Engineering Faculty Research & Creative Works

Skeletal muscle myopathy remains a significant cause of disability with limited treatment strategies. Advancements in tissue engineering have led to the development of borophosphate bioactive glasses (BPBGs) capable of enhancing skeletal muscle structure and function. Using a mouse model of severe myopathy (D2.mdx), we investigated muscle force, regeneration, angiogenesis and inflammation at 14, 70 and 140 days post-treatment (dpt). Tibialis anterior (TA) muscles of D2.mdx mice that received a single injection of cobalt oxide-doped BPBG (CoO-TRIM) particles exhibit greater active force, myofiber size, and regeneration through 70 dpt compared to control D2.mdx mice injected with Saline. Vascular endothelial growth factor …

Advancing Activated Carbon Production: Utilizing Pine Pruning Biochar Via Induction Heating With Co2and Iron-Based Catalysts, Ahmet Erdem, Muthanna H. Al-Dahhan, Ahmed Jasim

Chemical and Biochemical Engineering Faculty Research & Creative Works

This study introduces an induction heating approach for producing activated carbon from biochar obtained by thermal degradation of pine pruning waste from timber-related industries, using CO₂ and iron-based catalysts as activation agents. Activation experiments were performed using a 10 kW high-frequency induction system (28–40 kHz) under continuous CO₂ flow (15 mL min⁻¹), with electric current intensities of 200, 300, 400, and 500 A (corresponding to 700–1100°C) and durations of 30, 60, and 90 min, employing 45 g of iron-based catalysts (Fe–Ni–Ti–C, 85:6:3:6 wt.%) per 3 g biochar (15:1 w/w). Mass loss increased from 13.7 % (200 A, …

Sustainable Pathways For Fish Waste Oil Valorization Into Biofuel: Process Synthesis And Case Study, Hany A. Elazab, Radhi H. Alazmi, Abdelrahman El-Bagalaty, Hossam Tammam, Mahmoud El-Sayed, Mohamed Omar, Fathi Shokry, Mamdouh A. Gadalla, Fatma H. Ashour, Thokozani Majozi

Chemical and Biochemical Engineering Faculty Research & Creative Works

Biodiesel is a promising, sustainable alternative to fossil fuels such as petrol and diesel. Currently, biodiesel can be produced from edible plant oils and non-edible sources and wastes. Notably, fish waste oil is a sustainable resource for transesterification reactions to produce biodiesel. This research proposes a general process design methodology to investigate the potential of biodiesel production from fish waste oil as a pathway for waste-to-energy. The methodology integrates Pinch Analysis principles and process simulation to optimize the energy efficiency of a process design. Real data are collected on fish waste from fish industries in Egypt, focusing on three regions …

Electroactive Pvdf/Ti3c2tx Mxene Functionalized Nanofiber Mats With High Surface Potential For High-Efficiency Indoor & Outdoor Submicron Pm(0.3-2)Μm Filtration, Ashish Kakoria, Mirza Muhammad Zaid, Aamir Iqbal, Mahsa Moradi, Lina Zheng, Guang Xu

Mining Engineering Faculty Research & Creative Works

Fine PM0.3-2.0 rapidly penetrates the respiratory system and causes health problems. Commercial filters remove 0.3 μm particles at ∼95 % efficiency but impose high pressure drops that make breathing difficult. We fabricate a novel electrospun PVDF-Ti₃C₂Tx nanofiber mat for PM0.3–2.0 filtration. Where a high electric field stretched PVDF and PVDF-Ti₃C₂Tx solutions into ultrafine fibers that were collected as porous nanofibrous mats. PVDF was chosen for its electroactive behavior and high dielectric constant, enabling efficient electrostatic filtration. The incorporation of Ti₃C₂Tx MXene enhances surface charge density and interfacial polarization, …

Applying Direct Numerical Simulations To Investigate Wave Forcing Against A Vertical Wall, Hunter Boswell, Frank D. Han, Gaurav Savant, Guirong Yan, Wouter Mostert

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Current engineering standards lack the ability to predict the peak impact forces of breaking waves impinging directly upon coastal structures. In this study solitary waves impacting vertical and tapered walls are investigated. To capture the detailed physics of the wave profile that impacts the wall, two-dimensional direct numerical simulations are applied to model the wave traveling over a simplified bathymetry consisting of an initially uniform depth, followed by a uniform beach ramp and then terminating in a uniform depth inshore region and vertical wall. Such an approach can simulate wave runup on land and then the impact with the vertical …

The Effect Of Si And Zr On The Formation Of Al3x And V-Phase In A 6005a Alloy With Sc—Part 1: Alloy Design And Heat Treatment Selection, Eli A. Harma, Timothy Langan, Paul Sanders

Michigan Tech Publications

Adding Sc to 6xxx series alloys has led to inconsistent results due to the formation of the high-temperature, thermodynamically stable V-phase (AlSc2Si2). Thermo-Calc single-axis equilibrium and phase diagram calculations were employed to identify V-phase formation with varying Si and Zr concentrations, indicating that increasing Zr and decreasing Si lowered the V-phase equilibrium volume fraction. Increasing Zr also shifted the V-phase equilibrium to higher Si concentrations. To access real-world influences of Zr and Si, four compositions were cast with different Si and Zr concentrations: a high-Si, low-Zr alloy; a medium-Si, medium-Zr alloy; a low-Si, high-Zr alloy; and a baseline alloy without …

On Signifiable Computability: Part Iii: A Note On Unnameable Functions On Natural Numbers, Vladimir A. Kulyukin

Computer Science Faculty and Staff Publications

A writing system 𝔚 on an alphabet 𝒜 is a tuple (ℜ,𝔐), where ℜ is a finite set of text formation rules and 𝔐 is a finite rule application mechanism that generates texts on 𝒜. A natural writing system forms natural language texts on an alphabet such as Sanskrit on Devanagari. An artificial writing system generates formal language texts on an alphabet such as Lisp on Unicode. Let ℕ ={0,1,2,…} be the set of natural numbers. A function on natural numbers 𝑓 :ℕ^𝑘 ↦ ℕ, 0 < 𝑘 ∈ ℕ, is nameable by a writing system on an alphabet if, and only if, the system can generate a text on the alphabet that names f and no other function. We show that there exist functions on natural numbers unnameable in principle in that they cannot be named by any writing system on any alphabet. Our results imply the following computability-theoretic hierarchy of functions on natural numbers: computable ⊊ partially computable ⊊ nameable ⊊ 𝔉, where 𝔉 is the set of functions on ℕ.

Mechanistic Framework Of Wood Decomposition In Post-Storm Vegetative Debris Piles Using Continuous Quality Theory, Thomas T. Lee

Master's Theses

Storm events generate significant quantities of vegetative debris composed of wood, branches, twigs, and other organic materials. Efficient post-storm resource recovery and carbon accounting depend on reliable predictions of decomposition within these large, heterogeneous debris piles. While small-scale wood decay is well studied, decomposition dynamics within multi-layer debris piles remain poorly characterized, limiting municipalities' ability to estimate material longevity and resource recovery potential.

To address this gap, this study develops the WOOD_DK (Wood Organic Oxidation and DegraDation Kinetics) model, a preliminary, exploratory one-dimensional multilayer decomposition framework simulating coupled temperature, moisture, oxygen, and carbon dynamics in MATLAB. Microbial decomposition follows Continuous …

A Simulation Framework For Edge Lane Roads And Bicycle Shared Roadways, Nick Sauciur

Master's Theses

Edge Lane Roads, also referred to as Advisory Bike Lanes, are a shared roadway treatment that designates space for cyclists while allowing flexible use of the roadway by motorists. They are commonly applied on lower speed corridors and can be used both where roadway width is limited and where agencies seek to manage vehicle speeds, clarify cyclist positioning, or improve shared roadway operations. The configuration provides visually designated space for cyclists while allowing motorists to encroach into that space when yielding to opposing traffic. Although interest in these facilities is growing in North America, quantitative tools for evaluating their operational …

Portable Ice Cube Maker, Ayden Ziegler, Emiliano Hansen, Wyatt Engdahl, Dane Hansen

Mechanical Engineering

This Final Design Report outlines the senior design project undertaken by a team of mechanical engineering students at California Polytechnic State University, San Luis Obispo, for the development of a portable backpacking ice cube maker. The project aims to design, build, and test a lightweight, compact device that produces ice cubes for backpackers in remote outdoor environments. The goal is to create a functional prototype that is durable, user-friendly, and suitable for backcountry use. This document details background research, project objectives, and project plan, and current design status.

Dvr Service Evaluation And Fee Sufficiency Study, Mallory Brown, Andrew Martin, Jeeyen Koo, Jennifer Walton

Kentucky Transportation Center Research Report

The Kentucky Transportation Cabinet’s (KYTC) Department of Vehicle Regulation (DVR) administers numerous fees and taxes. Many administered by the two divisions in DVR — Motor Vehicle Licensing (DMVL) and Motor Carriers (DMC) — have remained unchanged for many years despite salary increases, the adoption of more complex and expensive technologies, and inflation raising administrative costs. This report provides in-depth assessments of 10 fees and taxes (selected by division administrators). Six are administered by DMVL — certificate of title, duplicate title, vehicle title history report, additional registration fee, reflectorized license plate fund, and trailer registrations — and four are managed by …

Applying Two-Stage Risk-Based Market Structures For Energy Hub-Based Plug-In Electric Vehicles Using Information Decision Gap Theory And A Hybrid Recurrent Convolutional Network, A. Heidari, R. C. Bansal, R. Bo

Electrical and Computer Engineering Faculty Research & Creative Works

This paper investigates the optimal operation of an energy hub engaged in both day-ahead and real-time trading. A two-stage optimization framework Information Gap Decision Theory (IGDT) for day-ahead bidding and stochastic programming with Monte Carlo scenarios for real-time recourse is applied. Risk-neutral, risk-averse, and risk-taking strategies are considered to capture different risk preferences. The hub integrates combined heat and power, renewable energy, plug-in electric vehicles, and vehicle-to-grid and grid-to-vehicle technologies. Price and load forecasts are generated using a hybrid recurrent convolutional network (HRCN). Results highlight the trade-off between risk management and economic performance: costs are 16.5 % higher in the …

Acinetobacter Spp. With Lower Susceptibility To Quaternary Ammonium Compounds Enriched In Microbial Communities Of Frequently Used Sinks, M. C. Cruz, R. Ruhal, J. Lavin, S. Bridwell, N. Maghboli Balasjin, B. Raasch, R. Melton, Brooke K. Mayer, Christopher Marshall, Krassimira R. Hristova

Civil and Environmental Engineering Faculty Research and Publications

Sanitary environments that undergo frequent cleaning and disinfection may harbor microbial communities with potential health risks. While biofilms in healthcare settings are well studied, comparatively less is known about sink-drain microbiomes in public and educational buildings, where hundreds of people may interact with shared sink fixtures. This study characterized the spatial and temporal heterogeneity of sink-drain biofilm microbiomes in academic buildings. We sampled 16 sinks from two buildings (four floors each, with sinks closest and furthest to the bathroom entrance), which are cleaned daily with quaternary ammonium compound (QAC) disinfectants, during periods of low and high student traffic (during and …

The Illusion Of Causality In Llms: A Developmentally Grounded Analysis Of Semantic Scaffolding And Benchmark–Capability Mismatches, Daisuke Akiba

Publications and Research

Recent benchmarks increasingly report that large language models (LLMs) exhibit human-like causal reasoning abilities, including counterfactual inference and intervention planning. However, many such evaluations rely on domains that are heavily represented in training data and embed strong semantic cues, raising the possibility that apparent causal competence may reflect semantic pattern recombination rather than structure-sensitive causal reasoning. Drawing on human developmental theories of causal induction, this perspective argues that genuine causal understanding requires robustness to novelty and reliance on conditional structure rather than semantic familiarity. To illustrate the testability of this claim, the paper includes a pilot demonstration using synthetic causal …

Ƒ(Cell): Software For Reproducible Analysis Of Optoretinograms, Robert F. Cooper, Mina Gaffney, Brea D. Brennan, Niko Rios

Biomedical Engineering Faculty Research and Publications

Purpose: There has been a marked increase in use of a noninvasive functional imaging technique called optoretinography (ORG). As more groups use ORGs, it is crucial to have a consistent methodology, and understand what analysis parameters influence repeatability. In this work, we present an open-source software library called ƒ(Cell) designed to facilitate reproducible and repeatable analyses of ORG data.

Methods: We designed ƒ(Cell) as a Python software library that can co-register and analyze ORG datasets, while also enabling process auditing. To validate the software, we used our previously obtained normative optoretinography datasets as well as datasets from six …

Improving Interlimb Coordination And Paretic Limb Use After Stroke Using A Novel Robotic Split-Crank Pedaling Device: A Cross-Sectional Study, Tom S. Ruopp, Brian Schmit, Sheila Schindler-Ivens

Biomedical Engineering Faculty Research and Publications

Background. Many stroke survivors cannot walk effectively, even after rehabilitation. Causes include impaired muscle activation, poor interlimb coordination, and limited restorative interventions. To address this, we developed CUped (pronounced “cupid”), a motorized split-crank pedaling device designed to compel use of the paretic limb and retrain interlimb coordination. We examined its within-session effects, comparing three proportional control schemes—assist (A), resist (R), and assist plus resist (A + R)—to identify which best promotes recovery-related movement.

Methods. Nineteen individuals with stroke and eleven controls pedaled in 5-min bouts, one per control scheme. Each bout included pre-test, exposure, and post-test periods. Participants were instructed …

The Effect Of Reduction Of Input-Parameters On Data-Driven Prediction Of Critical Heat Flux In Rod Bundles Using Extended Parameters For Reactor Thermal–Hydraulic Safety, Rehan Zubair Khalid, Atif Khan, Farooq Ahmad, Muthanna H. Al-Dahhan, Atta Ullah

Chemical and Biochemical Engineering Faculty Research & Creative Works

Accurate prediction of the critical heat flux (CHF) is a key pillar for ensuring both the safety and economic performance of nuclear reactors. While machine learning (ML)-based methodologies have demonstrated considerable success in predicting CHF, most existing studies have been confined to simplified geometries, such as single tubes. Conversely, limited attention has been devoted to CHF prediction in realistic reactor environments, particularly within rod bundle configurations, where complex multiphase flow and heat transfer phenomena prevail. In this work we develop different AI models based on large dataset operating conditions as well as the complex geometric features of rod bundles. The …

Data-Driven Non-Precipitation Echo Removal Of Nexrad Radars Based On A Random Forest Classifier Using Polarimetric Observations And Goes-16 Data, Munsung Keem, Bong Chul Seo, Witold F. Krajewski, Sangdan Kim

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Highlights: What are the main findings? A Random Forest-based model using dual-polarimetric radar features achieves >99% accuracy in classifying precipitation and non-precipitation echoes. Multi-scale spatial variability features enhance discrimination between genuine precipitation and spurious echoes. Fusion of GOES-16 infrared satellite data with NEXRAD radar effectively removes non-precipitation echoes with precipitation-like signatures, including wind turbine clutter. A CAPPI scan strategy improves near-radar precipitation detection by recovering valid echoes misclassified at the lowest elevation due to side-lobe interference and limited sampling volume. What are the implications of the main findings? The model's robustness to noise and overfitting, combined with minimal hyperparameter tuning, …

Understanding Human Arm Stiffness Modulation In Overground Phri: The Roles Of Kinematics, Perturbation, And Trunk Sway, Mohsen Mohammadi Beirami, Sambad Regmi, Devin Michael Burns, Yun Seong Song

Psychological Science Faculty Research & Creative Works

This study examines human arm kinematics during overground physical human-robot interaction (pHRI). Previous work showed humans adjust arm stiffness with changing trajectory uncertainty, but the roles of arm kinematics and muscle activation remained unclear. Building on a preliminary study, we analyzed arm movements with more participants (10 individuals) to achieve more reliable findings and examined two potential influences that arose in the preliminary study: the robot's perturbation effect (a brief hand push) and left-to-right trunk sway. Using a linear mixed-effects model, we evaluated the effects of participant, block, and trajectory condition on arm angles. Results showed minimal kinematic contribution to …

Unhsc Scm Performance Fact Sheets, Unh Stormwater Center

UNH Stormwater Center

No abstract provided.

Cathy's Trike, Jameson Stengel, Victor Robles, Asher Becker

Mechanical Engineering

Cathy Hoenig needs a better way to safely steer her trike since she recently had her arm amputated at the elbow. Right now, the standard steering setup doesn’t work for her because it’s designed for someone with two arms. The main issue is that because she can't hold the steering bar with both hands, she loses control and stability while riding, which takes away from her freedom and independence. We’re looking to design some kind of support or adaptive steering system that’ll let her feel safe and confident on her trike again. Our goal is to create a solution that …

Bonderson Workbench, Han Xu, Aidan Robleto, Sean Murphy, Victor Duran

Mechanical Engineering

This project redesigns the existing creative workbenches in Cal Poly's Bonderson High Bay to improve mobility and functionality for students and staff in the Mechanical Engineering Department.

Fsae Bespoke Brake Calipers For Hub Motor Architecture, Connor William Vaughan, Liam Upton Walsh, Bradley Brian Kern

Mechanical Engineering

Brakes are the most critical safety system on any performance vehicle, and as Cal Poly Racing transitions their Formula SAE car from a single rear motor to a four-in-wheel motor setup with regenerative braking, the team identified an opportunity to develop a bespoke brake caliper tailored to their specific needs. This document outlines the research, design, manufacturing, and validation of custom front brake calipers designed to improve upon commercial motorcycle calipers in key areas such as serviceability, mounting rigidity, thermal behavior, mass, and hub motor integration. The resulting design is a two-piece, four-piston, radially-mounted aluminum caliper featuring titanium pistons, toolless …

Microwave Dielectric Properties Of Geopolymer Precursor Powders, Linh T. Duong, Abu Naser Rashid Reza, Kristen M. Donnell, Christopher R. Shearer

Electrical and Computer Engineering Faculty Research & Creative Works

Geopolymers are sustainable structural materials with properties similar to ordinary Portland cement concrete. To better understand the fundamental reaction mechanisms of geopolymers, a microwave materials characterization approach is used. In this research work, the dielectric properties (permittivity and loss factor) of common precursor powders used to make geopolymers (GPPs)—fly ash, lime, metakaolin, silica fume, slag, and zeolite—are measured over the S- and X-band frequency ranges (i.e., 2.0–4.0 GHz and 8.2–12.4 GHz, respectively). The physical characteristics, elemental composition, mineralogical properties, and phase characterization of the GPPs are then correlated to dielectric properties. Permittivity of GPP, classified as pozzolanic or latent hydraulic, …

Feedback In Digital Game-Based Learning: A Taxonomy And The Design And Empirical Evaluation Of A Feedback System In A Mathematics Serious Game, André Almo

Dissertations

Digital Game-Based Learning (DGBL) is an active, student-centred pedagogical approach in which feedback plays a central role by informing learners’ actions, guiding decision-making and shaping motivation and engagement. Despite its importance, feedback in serious games is often described inconsistently and insufficiently in research, limiting comparability across studies and the accumulation of design knowledge, particularly for children. This thesis addresses these gaps through two complementary contributions: the development of a taxonomy for feedback design in digital serious games and the empirical evaluation of a taxonomy-informed feedback system in a mathematics game for primary school students. First, this work introduces the Taxonomy …

Explainable Machine Learning And Life Cycle Assessment For Sustainable Design Of Fiber-Reinforced Asphalt Concrete, Xiao Tan, Jianglei Xing, Soroush Mahjoubi, Pengwei Guo, Ziyao Wei, Yuan Wang, Jie Ren, Li Ai, Weina Meng, Yi Bao

Civil Engineering Faculty Publications

Conventional asphalt concrete has a limited lifespan due to cracking, deformation, and environmental degradation, driving the development of fiber-reinforced asphalt concrete (FRAC). However, key gaps remain in current data-driven FRAC studies due to small and homogeneous datasets, “black-box” machine learning models, and trade-offs between mechanical-sustainable performance, failing to provide a transparent understanding of features governing FRAC behaviors. This paper proposes a framework integrating explainable artificial intelligence and life cycle assessment (LCA) to advance mechanical and sustainable design of FRAC. A dataset of 2490 laboratory samples covers 15 input features and 3 mechanical outputs. Eight machine learning models, along with a …

State Of Charge Estimation Of Ev Secondary Battery Pack Using Hybrid Hedge Feedforward Feedback-Based Gated Recurrent Unit To Extend Lifespan, Md Ohirul Qays, Iftekhar Ahmad, Daryoush Habibi, Mohammad A.S. Masoum, Paul Moses

Research outputs 2022 to 2026

Accurate estimation of state of charge (SoC) and maintaining balanced charge levels across secondary battery cells are crucial in battery management systems (BMSs) to extend battery life while improving the performance and thermal stability of Li-ion batteries (LIBs) in electric vehicles (EVs). However, there are still underexplored challenges associated with circulating currents in electrochemical cells during continuous operation which can overheat battery packs, reducing their life span or result in dangerous thermal runaways. This paper investigates SoC estimation using various real-world charging and discharging profiles, along with charge-balancing strategies to enhance the longevity of parallel-connected Li-ion battery cells. A newly …