Engineering Commons^™

Cluster-Based Volt/Var Optimization On A Utility Distribution Feeder With Forecasted Ev Penetration, Steven B. Poore, Grant M. Fischer, Rosemary E. Alden, Evan S. Jones, Aron Patrick, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

With significant increase in EV adoption expected in the near future and the associated impacts on power systems, the effect of volt/var optimization (VVO) as the next step to conservation voltage reduction (CVR), requires reevaluation. Implementation of a cluster-based VVO control strategy employs a novel approach with machine learning (ML) load forecasting to reduce device adjustments through k-means clustering of contiguous time steps with similar active power load in which a single adjustment would be sufficient. The cluster-based VVO method is tested on a complex real world utility distribution feeder with 2,018 nodes, 8.65MW peak load, 9 capacitor banks (CBs), …

Hybrid Fea And Meta-Modeling For De Optimization Of A Pm Stator-Excited Motor With A Reluctance Rotor, Oluwaseun A. Badewa, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper presents an innovative method for designing high-performance electric motors by integrating machine learning (ML) based meta-modeling with a differential evolution (DE) optimization algorithm. The approach utilizes finite element analysis (FEA) data to train the ML meta-model, allowing for efficient optimization of high-power-density machines, such as the reluctance rotor and permanent magnet (PM) stator combined excitation motor, which is characterized by nonlinearities. The meta-modeling process employs an Artificial Neural Network (ANN) with 3 hidden layers and uses the motor’s geometrical variables as inputs. The accuracy of the meta-model in capturing the nonlinear relationships between design parameters, core losses, and …

Three And Two Phase Rotating Field Inductive Couplers For Wireless Power Transfer With One Phase Per Layer Windings, Donovin D. Lewis, Lucas Gastineau, Omer Onar, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Multiphase inductive wireless charging coils have been proposed recently to improve coupler surface power density, reduce component stress and size, and provide near-constant power delivery to charge mobile electric systems. Several aspects for the fundamental characterization of multiphase coils are explored up to six phases including approximate mutual inductance with size and turn variation, induced voltage, and output power estimation. The relative component stress and size of passive components for resonant operation are compared between the multiphase variants. A combination of an experimentally validated 3D electromagnetic finite element analysis (FEA) and power electronic co-simulations are used to validate the estimated …

Cryogenic Thermal System For Coreless Axial Flux Pm Machine With Litz Wire Winding For Electric Aircraft Propulsion, Matin Vatani, Chaianan Sailabada, Philippe Masson, Juan C. Ordonez, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Electric machines for aviation demand ultra-efficient, compact designs with high specific power density, which can be achieved through advancements in both electromagnetic design and thermal management. This paper proposes and investigates an integrated thermal management approach for a coreless stator axial flux permanent magnet (AFPM) machine featuring a double-sided Halbach array PM rotor, two stators, and an aluminum nitride (AlN) cold plate positioned between the stators for direct cooling. The cold plate incorporates internal serpentine channels for liquid hydrogen circulation. The electromagnetic performance and efficiency of the machine at cryogenic temperatures are assessed using temperature-dependent data from the literature, indicating …

Mitigation Of Pm Eddy Current Losses Using Offset Windings In Coreless Afpm Machines, Matin Vatani, Diego A. Lopez Guerrero, John F. Eastham, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Permanent magnet eddy current losses can become substantial in coreless stator axial flux permanent magnet (AFPM) machines operating at high speeds and under high electric loading, potentially leading to elevated temperatures and an increased risk of demagnetization. This paper investigates the origins of these losses through a detailed harmonic analysis of the winding factor and introduces a mitigation strategy. The proposed method utilizes two-layer offset windings, effectively minimizing undesirable armature flux harmonics through harmonic interaction between the offset layers. Two cases are studied: one in which each stator layer is connected to a separate inverter and another in which both …

Research Into Job Classifications For Kentucky Department Of Vehicle Regulation Employees, Mallory Brown, Andrew Martin, Jeeyen Koo, Jennifer Walton

Kentucky Transportation Center Research Report

The Kentucky Department of Vehicle Regulation (DVR) faces persistent challenges with employee recruitment, retention, and workforce alignment due to outdated job classifications and compensation structures. This study investigates if DVR’s reliance on the general Administrative Specialist job series is warranted given the duties performed by its staff. Through a job task analysis, financial modeling, and personnel data review, researchers assessed the feasibility of introducing a new DVR-specific job series based on the Vehicle Regulation Specialist (VRS) position currently being used by the Division of Motor Carriers. The proposed VRS series includes two levels — VRS I (Grade 13) and VRS …

Development And Evaluation Of A Simple Human Body Link Model Considering The Degrees-Of-Freedom Of Shoulders, Mizuki Takeda, Yuki Saito, Kaiji Sato

Progress in Scale Modeling, an International Journal

Modeling of the human body is widely utilized in the field of human–robot interaction, warranting the development of a simple model to measure and recognize the human body movements. To this end, a two-dimensional (2D) human body link model in the sagittal plane has been used to represent the human body with rotating joints and links connecting these joints. The joint positions can be determined by using the coordinates of a limited number of points on the links and estimated using a few sensor outputs when the links are of constant length. However, models with constant link lengths may result …

A Review Of Disassembly Systems For Circular Product Design, Giovanni Formentini, Joao Pj. Prioli, Junwon Ko, Buddhika M. Hapuwatte, Vincenzo Ferrero, Fazleena Badurdeen, Jeremy L. Rickli, Devarajan Ramanujan

Mechanical Engineering Faculty Publications

Circular Economy (CE) is described as a means for maintaining products and materials in circulation while regenerating nature. This shift requires considering aspects at the product design phase that were not previously prioritized. One such aspect, disassembly, is a key enabler for CE. Design for Disassembly methodologies have been deployed for several years to enhance disassembly performance. However, when CE is of interest, it is essential to consider how disassembly affects the entire product life cycle system. In this regard, this paper proposes a literature review of relevant DfD methods from a system engineering perspective to evaluate their effects on …

On The Optimal Design Of Coreless Afpm Machines With Halbach Array Rotors For Electric Aircraft Propulsion, Matin Vatani, John F. Eastham, Xiaoze Pei, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper provides a comprehensive analysis of the winding factor and winding harmonic distribution in coreless stator axial flux permanent magnet (AFPM) machines. The topology of this type of machine and its similarities to conventional cored AFPM machines are discussed. Popular pole/coil number combinations in coreless stator AFPM machines are identified and analyzed in detail. It is demonstrated that the winding factor in these machines varies with radius and can be expressed as the product of the conductor distribution factor, pitch factor, and coil group factor. The formulas for each factor are derived and presented in multiple forms based on …

Hybrid Fea And Meta-Modeling For De Optimization Of A Highly Saturated Spoke Ipm, Oluwaseun A. Badewa, Marcelo Silva, Rosemary E. Alden, Pedram Asef, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper introduces a novel approach for high performance electric motor design that combines machine learning (ML)-based meta-modeling with a differential evolution (DE) optimization algorithm. The method leverages finite element analysis (FEA) results to train the ML meta-model, enabling efficient design optimization for high-power density cored machines, such as spoke interior permanent magnet motors (IPM), which exhibit complex nonlinearities and saturation effects. This hybrid ML-DE framework seeks to provide an alternative for physics-based electric motor design and optimization, offering significant reductions in computational effort while maintaining accuracy. The meta-model’s accuracy in capturing the nonlinear relationships between design parameters, core losses, …

Optimal Design Of Coreless Axial Flux Pm Machines Using A Hybrid Machine Learning And Differential Evolution Method, Matin Vatani, David R. Stewart, Pedram Asef, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Coreless stator axial flux permanent magnet (AFPM) machines require computationally intensive three dimensional finite element analysis (FEA) for accurate performance evaluation, making optimization time-consuming and impractical for large-scale design studies. This paper presents a hybrid optimization approach that integrates differential evolution (DE) with artificial neural networks (ANNs) to accelerate the optimization of coreless AFPM machines. In this method, DE driven FEA simulations generate a dataset used to train an ANN surrogate model, significantly reducing reliance on direct FEA computations. The effectiveness of this approach is demonstrated through a multi-objective DE optimization, where the ANN’s predictions are validated against FEA results. …

Winding Factors And Harmonics Of Coreless Axial Flux Pm Machines, Matin Vatani, John F. Eastham, Xiaoze Pei, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper provides a comprehensive analysis of the winding factor and winding harmonic distribution in coreless stator axial flux permanent magnet (AFPM) machines. The topology of this type of machine and its similarities to conventional cored AFPM machines are discussed. Popular pole/coil number combinations in coreless stator AFPM machines are identified and analyzed in detail. It is demonstrated that the winding factor in these machines varies with radius and can be expressed as the product of the conductor distribution factor, pitch factor, and coil group factor. The formulas for each factor are derived and presented in multiple forms based on …

Smart Home Hvac Digital Twin Ml Meta-Model For Electric Power Distribution Systems With Solar Pv And Cta-2045 Controls, Rosemary E. Alden, Evan S. Jones, Steven B. Poore, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

Building modeling, specifically heating, ventilation, and air conditioning (HVAC) load and equivalent energy storage calculations, represent a key focus for decarbonization of buildings and smart grid controls. In this paper, an ultra-fast one minute resolution Hybrid Machine Learning Model (HMLM) is proposed as part of a novel contribution in the field of residential physics-based smart home surrogate modeling. Emulation of white box models, or digital twins, with editable parameters through machine learning (ML) meta-modeling serves as an alternative to wide-spread experimental big data collection. The HMLM employs combined k-means clustering with multiple linear regression (MLR) to emulate minutely HVAC power …

Development Of Measures For Highway Criticality Assessment, Xu Zhang, Mei Chen

Kentucky Transportation Center Research Report

Existing network criticality assessments, often biased towards heavily used highways in populous areas by incorporating traffic and sociodemographic attributes, can lead to an underestimation of the vital role of rural infrastructure. Consequently, rural highways, particularly low-volume roads, often receive less consideration despite their critical role in network connectivity and local access to services and economic opportunities. To address this, we develop a criticality framework based on the egalitarian principle, which prioritizes equitable consideration of all network links regardless of traffic volume or population density, comprising two complementary measures. First, the normalized betweenness centrality quantifies a road's relative importance in efficiently …

Characterization, Performance, And Toxicological Assessment Of Polysulfone-Sulfonated Polyether Ether Ketone Membranes For Water Separation Applications, Muhammad Usman Yousaf, Lucca Madeo Cortarelli, Nerissa I. Jebet, Jason M. Unrine, Nirupam Aich, Olga V. Tsyusko, Isabel C. Escobar

Markey Cancer Center Faculty Publications

The removal of small molecular weight charged compounds from aqueous solutions using membrane remains a challenge. In this study, polysulfone (PSf)- and sulfonated polyether ether ketone (SPEEK)-based membranes were fabricated via non- solvent induced phase separation process (NIPS) using N-Methyl-2-Pyrrolidone (NMP) as solvent and water as non-solvent. Membranes were characterized structurally and morphologically, followed by toxicity assessment conducted before and after filtration, both with and without annealing at various pH values to evaluate potential leaching of trapped solvent from the membrane pores. Additionally, membrane performance was characterized using binary mixtures of cationic and anionic dyes. The results demonstrated selective filtration …

Current Practices In Rock Scaling, Daryl J. Greer, Kean H. Ashurst Jr

Kentucky Transportation Center Research Report

Rockfalls, which result from the chemical and physical weathering of aging exposed rock cuts, occur frequently along many Kentucky roadways and can endanger travelers. Mitigating rockfalls often requires substantial excavation, procuring additional right of way, and/or hiring specialty contractors. An alternative to these expensive processes is rock scaling, which can be a cost-effective tool for mitigating rockfalls. Rock scaling entails removing loose and unstable rocks from rock cut slopes within the right of way to reduce rockfall risk and is being used with increased frequency by state transportation agencies around the country. The Kentucky Transportation Cabinet (KYTC) has completed several …

Bridge Load Posting Based On Load Testing, Cody Hutchinson, Abheetha Peiris, Issam Harik

Kentucky Transportation Center Research Report

AASHTO’s Manual for Bridge Evaluation (MBE) provides guidance for analytically evaluating bridge capacity based on available design information and the results of field inspections. This analysis results in a rating factor (RF), which quantifies a bridge’s safe load carrying capacity. RF accuracy, however, depends on the availability of information about structural details and material properties. As such, load rating bridges without design plans is difficult as field inspections alone often cannot provide enough information to perform detailed analysis. In many instances this means that a bridge would possess a substandard rating factor (RF < 1.0) simply due to the conservative assumptions required to perform traditional analysis. The most effective method for safely modifying such conservative theoretical rating factors is through load testing. Load testing measures actual bridge behavior and, for most bridges in good health, finds an increase in load rating is justified. This project utilized load testing to load rate 14 bridges in Kentucky that lack structural plans. Researchers first determined theoretical ratings using MBE-prescribed methods. For information typically taken from design plans, but which could not be measured directly, data-backed methods for making conservative assumptions were developed. For most bridges included in the study, theoretical rating factors alone suggested load postings were necessary. Load testing was then carried out utilizing tandem rear-axle dump trucks with measured axle weights. Multiple single-lane load cases were selected to maximize the effects being rated. Strain data were collected in real time using a wireless reusable strain gage system. Using these data, researchers computed a field test adjustment factor using MBE methods which directly modified the calculated theoretical RFs. Ultimately, load testing provided sufficient evidence to safely recommend that load postings were not necessary for any bridges in this study.

Lagrange Multipliers As A Metric For Early-Stage Shipboard Power System Design, Magdalen A. Barnes

Theses and Dissertations--Electrical and Computer Engineering

Integrated power systems are essential in the operation of electric ships and must function under a diverse range of conditions. In addition to routine operation, ships should be prepared to respond to challenging events that require significant amounts of power. Demanding scenarios, coupled with complex and interconnected power systems, present challenging issues. The power and energy ratings of equipment are crucial factors in the operational success of the ship; however, to meet economic constraints, balance between performance and cost must be upheld. Details regarding equipment models and specifications are typically unavailable during early-stage design. Power system modeling and simulation can …

A Systems-Based Framework For Product Circularity Assessment, Gisele Bortolaz Guedes, Junwon Ko, Fazleena Badurdeen, I. S. Jawahir, K. C. Morris, Vincenzo Ferrero

Mechanical Engineering Faculty Publications

One of the key aspects of Circular Economy (CE), particularly when focusing on the product level, lies in its emphasis on designing products to facilitate the circulation of resources and maximize value throughout their entire lifecycle. To effectively develop such products an understanding of the characteristics of circular products (CP) is needed. Adopting a systems perspective that considers the total lifecycle and stakeholders involved and recognizing interdependencies among them is essential for identifying factors that characterize CPs. Existing methods for assessing product circularity do not identify all factors that charac- terize CPs and have limitations in the measurement methods proposed, …

The Rhythm Of Renewables: Minute-By-Minute Insights From Kentucky, David S. Beyerle, Noah M. Stewart, Shaun E. Lavin, Chad C. Alkire, Heather Nikolic, Samuel Kelty, Ezekiel A. Boggs, Declan Boyle, Lawrence E. Holloway, Aron Patrick

Electrical and Computer Engineering Faculty Publications

Kentucky’s renewable energy landscape beats with a distinct rhythm shaped by ever-changing variations in sunlight, wind, rainfall, and the ever-modernizing grid that connects them. This paper analyzes minute-by-minute performance data from seven renewable and storage assets owned and operated by the PPL Corporation in Kentucky, including hydroelectric, solar, wind, and lithium-ion battery systems. Using a full year of synchronized, high-resolution data from multiple sites in the Commonwealth, the study examines daily and seasonal capacity factor trends, explores correlations among generation types, and evaluates their alignment with utility load profiles. Our analysis found 279 hours—about 3.2% of the year—with zero renewable …

Smart Homes, Grids, And Electric Vehicles Large-Scale Integration Studies Employing Machine Learning And Optimization Techniques, Rosemary E. Alden

Theses and Dissertations--Electrical and Computer Engineering

Residential digital twins are fundamental to the smart grid transition, and thus, must be both accurate and representative of existing homes and scalable for large distribution systems. Within this dissertation, new machine learning (ML) and physics-based methodologies are applied to the major individual residential loads, energy storage devices, and resources in the US to develop computationally efficient digital twins and new optimal control strategies for the virtual power plant (VPP) concept. Big data from experimental field demonstrations with dedicated metering, thousands of residential smart meter profiles, and large national human behavior surveys are employed to develop ultra-fast scalable residential load …

An Improved Machining Temperature Prediction Model For Aerospace Alloys: Effect Of Cutting Edge Radius And Tool Wear, Jonathan Theraroz, Oguzhan Tuysuz, Julius Schoop

Mechanical Engineering Faculty Publications

Temperature rise during machining impacts the workpiece material properties, residual stresses, surface and sub-surface quality. Experimental, numerical, and analytical methods have been used to predict the temperature fields in the tool, workpiece and chip. Each approach has its limitations: experimental techniques are cumbersome with expensive equipment, and numerical modeling is computationally inefficient. Existing analytical models only consider the effect of wear while ignoring the edge radius, though the latter changes with the flank wear in practice. To address this limitation, this article proposes an improved analytical temperature prediction model for orthogonal machining by introducing discrete linear heat sources on the …

Voltage And Var Control And Real-Time Digital Simulator-Based Protection System Testing For Power Distribution Systems, Gaurav Yadav

Theses and Dissertations--Electrical and Computer Engineering

Rising power demand calls for electric distribution systems to manage peak load. One option is reducing feeder voltage, which lowers voltage-dependent load demand and may also reduce energy usage. The technique, known as Conservation Voltage Reduction (CVR), may operate independently or within a volt/var control system. This dissertation examines CVR factor calculation using measurements collected at the substation, and proposes a curve-fitting and artificial neural network method to estimate active power losses using input active power, reactive power, and substation voltage. As utilities integrate more inverter-based resources (IBRs) to support increasing demand, rapid voltage fluctuations arise due to the intermittent …

A Framework For Ai Implementation In Construction: Use Cases, Challenges, And Benefits For Contractors, Jaqueline De Aquino Leite Gomes

Theses and Dissertations--Civil Engineering

The construction industry is one of the most important sectors that contribute to the economy worldwide, but it has been very slow in adopting digital transformation. Artificial Intelligence is the backbone of digital innovation, and it can help solve inefficiencies, improve safety, and enhance decision-making in construction. This thesis reviews 85 academic papers, identifies 354 AI use-cases, 180 benefits, and 173 challenges. Key findings have looked at the role of AI in safety monitoring, design optimization, and operational efficiency, while barriers involve data scarcity, high costs, and readiness of the workforce.

All of these challenges have one very handy framework …

Multi-Scale Computational Mechanical Modeling Of Complex Multi-Phase Materials Systems, Naji Al-Mashrafi

Theses and Dissertations--Chemical and Materials Engineering

This thesis employs finite-element–based computational methods to investigate how microstructural features and material heterogeneity govern mechanical behavior across three distinct complex systems. First, the elastic response of open-cell metallic foams is analyzed using large ensembles of model RVEs generated with the Kentucky Random Structures Toolkit (KRaSTk); finite-element homogenization reveals that effective stiffness is not dictated by relative density alone, as the skewness of ligament-length distributions—captured by the second Pearson’s coefficient—exerts a strong and previously unrecognized influence, with structures enriched in short load-bearing ligaments exhibiting consistently higher stiffness even at fixed density and connectivity. The second study examines heterogeneous polycrystalline solids …

Seasonal Variation Of The Stream’S Autogenic Sediment Transport Regime, Melissa Beckman

Theses and Dissertations--Civil Engineering

This thesis investigates the autogenic sediment transport regime in a low-gradient stream system in the inner bluegrass region of central Kentucky, USA The seasonality of sediment transport seasonality was not well addressed in prior research for baseflow and low flow periods, to our knowledge, due to the assumption that low flows do not account for considerable fluid transport capacity to move sediment. The hypothesis is that during the autogenic regime the sediment transport in the low-gradient system is being driven by geophysical, biogeochemical, and biological processes. We hypothesize that crayfish are one mechanical driver of sediment transport during these periods. …

Enhanced Separation Performance For Fractionally Liberated Materials Using The Hydrofloat™ Process Technology, Yucel Ozsoy

Theses and Dissertations--Mining Engineering

The advent of HydroFloat™ technology, developed by Eriez Manufacturing, marks a significant milestone in the evolution of the mineral processing industry, particularly for the coarse particle flotation by shifting the limits, well-known as the “Elephant Curve.” As the industry strives to process lower-grade ores with higher tonnages for financial reasons, the significance of processing coarse particles through HydroFloat™ technology becomes increasingly critical.

This approach offers substantial benefits by potentially reducing energy consumption within grinding circuits, making it a key solution in enhancing efficiency and cost-effectiveness. This study presents a comprehensive review of the existing literature, laying a solid foundation by …

Implications Of Nutrient Fate And Transport Following Nanopesticide Applications In Agricultural Field Plots In Central Kentucky, William Rud, Manuel D. Montaño, Daniel M. Miller, Wayne T. Sanderson, Carmen Agouridis, Brianna F. Benner, Tiffany L. Messer

Biosystems and Agricultural Engineering Faculty Publications

The potential benefits of nanopesticide use over standard pesticides include more precise application at reduced application rates, lower premature degradation, and decreased direct impacts to target organisms. However, field scale investigations of the fate and transport of common nanopesticides such as copper (II) hydroxide and imidacloprid combinations, remain limited. A field study evaluating nano-scale copper (II) hydroxide (Cu), standard imidacloprid (I), nanoimidicloprid (NI), and nano-scale copper (II) hydroxide and imidacloprid (CuNI) compared to control (C) plots was conducted using thirty 14.6 m² field plots to determine the impacts of nanopesticide applications on nutrient cycling and quantify the persistence of …

Design And Comparative Analysis Of Electric Motors With “Flux-Switching” Effect Having Reluctance Rotors And Pm Or Dc Stator Excitation, Oluwaseun A. Badewa, Ali Mohammadi, Donovin D. Lewis, Somasundaram Essakiappan, Madhav Manjrekar, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper introduces innovative designs for synchronous electric motors with phase coils and permanent magnets (PM) or DC-excitation coils embedded in the stator. Alongside concentrated phase coils in dedicated slots, the spoke-type PMs offer high flux intensification, while the option for DC-excitation coils eliminates demagnetization risks. Since the rotor has no active electromagnetic components, the machine can achieve high-speed operation while enabling advanced cooling systems focused solely on the stator. A special implementation with a “wave” or “serpentine” DC-excitation winding which has the potential for reduced losses depending on the motor aspect ratio is presented. The operation, control, and polarity …

Harmonic And Non-Linear Effects On The Parameters And Performance Of A Vernier Machine With Flux Concentrating Spoke Rotor, Ali Mohammadi, Yaser Chulaee, Aaron M. Cramer, Ion G. Boldea, Dan M. Ionel

Electrical and Computer Engineering Graduate Research

This paper presents a systematic study on the MAGNUS machine, which is an innovative dual-stator axial flux permanent magnet vernier machine (AFPMVM). The MAGNUS machine features a novel single-wound dual-stator design with minimal slots and an exceptionally high-polarity spoke-type permanent magnet rotor, which enables a very high flux concentration ratio. The operating principle of vernier machines is derived, showing the possible slot-pole combinations. Inductance components are introduced, and multiple methods are employed to determine the direct and quadrature axis inductances, revealing that despite its spoke-type rotor, due to a high harmonic content and a high differential leakage inductance, the MAGNUS …