Engineering Commons^™

Tribological Studies Of Thick Polytetrafluoroethylene Coatings Enhanced By Polydopamine And Nanoparticles, Sujan Kumar Ghosh

Graduate Theses and Dissertations

Polytetrafluoroethylene (PTFE) is a popular low friction solid lubricant with high chemical and thermal stability. Thick PTFE coatings have the potential for many tribological applications, such as replacing Tin-based Babbitt materials in journal bearings. However, the weak bonding strength to the substrate and the high wear rate of PTFE coatings are current limiting factors. The lack of understanding of their tribological properties and wear mechanisms in oil-lubricated conditions and how coating thickness affects the tribological performance further hindered the use of PTFE coatings. In this dissertation, polydopamine (PDA), a bio-inspired adhesive, is used as an underlayer for or as a …

Applications Of Masw And Mhvsr Techniques For Infrastructure Evaluation With A Focus On The Effects Of Different Transformation Techniques And Near-Field Effects On Derived Dispersion Data, Salman Rahimi

Graduate Theses and Dissertations

This dissertation is aimed at understanding two aspects of active surface wave methods to improve the accuracy and reliability of this method. These include (1) the performance of four common wavefield transformation methods for the multichannel analysis of surface wave (MASW) data processing and (2) near-field effects. Toward this end, extensive field measurements were conducted considering different factors affecting these two topics. The MASW and microtremor horizontal to vertical spectral ratio (MHVSR) were then employed to examine their efficiency for infrastructure health monitoring.

Regarding the performance of the four common transformation techniques, it was observed that for sites with a …

Development Of Novel Battery Materials For Lithium-Ion Batteries And Beyond, Jiyu Cai

Graduate Theses and Dissertations

As fossil fuels are depleting and causing environmental issues, it becomes imperative to widely implement renewable energies (e.g., solar and wind power). In this context, electrical energy storage (EES) systems are essential to accommodate the intermittent supply and uneven distribution of renewable energies. To this end, high-energy-density EES devices are highly demanded, such as rechargeable batteries. This dissertation presents my efforts in developing novel battery materials for lithium-ion batteries (LIBs), sodium-ion batteries (SIBs), and solidstate lithium batteries (SSLBs). These efforts include electrochemical evaluations of battery materials, surface modifications of electrodes via atomic layer deposition (ALD), and advanced characterizations of batteries …

Phase-Field Modeling Of The Polymer Membrane Formation Process For Micro- And Ultra-Filtration, Michael Rosario Cervellere

Graduate Theses and Dissertations

Porous polymer membrane filters are widely used in separation and filtration process. Micro- and ultra-filtration membranes are commonly used in biopharmaceutical applications such as filtering viruses and separating proteins from a carrier solution. The formation of these membrane filters via phase inversion is a complex and interconnected process where varying casting conditions can have a wide variety of effects on the final membrane morphol- ogy. Tailoring membrane filters for specific performance characteristics is a tedious and time consuming process. The time and length scales of membrane formation make it extremely difficult to experimentally observe membrane formation. Modeling the membrane formation …

Data-Driven Methods To Address Truck Parking Shortages For Long-Haul Commercial Truck Drivers, Sharif Mahmud

Graduate Theses and Dissertations

Truck parking is a critical concern for both the trucking industry and the truck drivers. Long-haul commercial truck drivers rely on safe and adequate parking to support interstate commerce, which has become a challenge due to parking shortages. The recent electronic logging device (ELD) mandate, forcing a strict compliance to hours of service (HOS) regulations, are leading to higher demand for parking. A number of federal, regional, and local studies reveal that truck activity will increase and truck parking demand will outpace parking supply in the coming years. Such parking shortages likely disrupt freight flows and pose risks to truck …

Mitigating Calcium Oxychloride Damage In Cementitious Paste And Concrete Utilizing Supplementary Cementitious Materials, Casey Jones

Graduate Theses and Dissertations

It is understood among engineers in the United States (U.S.) that improvement is needed throughout the transportation infrastructure. In the 2021 Infrastructure Report Card produced by the American Society of Civil Engineers, the roadways of this nation merit a D. This leaves room for improvement in order to provide durable pavements throughout this nation. Areas with significant winter weather may have exacerbated effects in decreased roadway longevity due to freezing/thawing cycles and the use of chemical deicers to mitigate gelid roadway conditions. Much research focuses on surface scaling and reinforcement corrosion using these materials; however, joint deterioration, due to chemical …

Influence Of Extracellular Matrix Stiffness And Topography On Neuronal Cell Behavior And Neurite Outgrowth, Mohan Yasodharababu

Graduate Theses and Dissertations

The focus of regeneration therapy for traumatic brain injuries and Alzheimer's disease is on the promotion and growth of neuronal cells. In vitro research attempts to improve this by modifying the stiffness and topography of the extracellular matrix (ECM). However, the limitations of in vitro experiments make it difficult to control the individual factors influencing neuronal cell growth. A computational model can be used to decouple individual factors and study them individually to gain a better understanding of the mechanics between the neuronal cell and ECM, which will aid in the design of in vitro experimental studies.

This study develops …

Random Packing Material In Disinfection Contactors: Effects On Baffling And Energy Loss, Jessica L. Baker, Subhas K. Venayagamoorthy, Susan K. De Long

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This study investigates the potential improvement in the hydraulic disinfection efficiency and the possible energy loss as a result of the presence of random packing material (RPM) in a laboratory-scale chlorine contactor. Tracer tests were conducted on a 55-gal drum tank filled with RPM in varying amounts in different configurations to measure the efficiency of each setup in terms of baffling factor (BF). The bulk pressure drop was measured to determine the energy loss for each configuration. The results of this study show that securing RPM near the inlet, in any amount, improves the BF by 300% to more than …

A New Heuristic Algorithm For Accuracy And Computational Efficiency For Solving Minimum Cost Flow Problems, Timothy Michael Chávez

Computational Modeling & Simulation Engineering Theses & Dissertations

While the minimum cost flow (MCF) problems have been well documented in many publications, due to its broad applications, little or no effort has been devoted to explaining the algorithms for identifying loop formation and computing the θ value needed to solve MCF network problems. This paper proposes efficient numerical procedures and MATLAB computer implementation for computing the θ value. Furthermore, this paper also proposes a mixed heuristic, shortest path (SP) Chavez-Nguyen (or Chayen) Algorithm in Phase 1 (to obtain the basic feasible solution) and, either the conventional MCF or MATLAB’s built-in Linprog() function, in Phase 2 (to obtain the …

Effects Of Memristive Synapse Radiation Interactions On Learning In Spiking Neural Networks, Sumedha Gandharava Dahl, Robert C. Ivans, Kurtis D. Cantley

Electrical and Computer Engineering Faculty Publications and Presentations

This study uses advanced modeling and simulation to explore the effects of external events such as radiation interactions on the synaptic devices in an electronic spiking neural network. Specifically, the networks are trained using the spike-timing-dependent plasticity (STDP) learning rule to recognize spatio-temporal patterns (STPs) representing 25 and 100-pixel characters. Memristive synapses based on a TiO₂ non-linear drift model designed in Verilog-A are utilized, with STDP learning behavior achieved through bi-phasic pre- and post-synaptic action potentials. The models are modified to include experimentally observed state-altering and ionizing radiation effects on the device. It is found that radiation interactions tend …

The Influence Of Participation In A Multi-Disciplinary Collaborative Service Learning Project On The Effectiveness Of Team Members In A 100-Level Mechanical Engineering Class, Stacie I. Ringleb, Pilar Pazos, Julia Noginova, Francisco Cima, Orlando Ayala, Krishnanand Kaipa, Jennifer Kidd, Kristie Gutierrez

Mechanical & Aerospace Engineering Faculty Publications

Engineers need to develop professional skills, including the ability to work successfully in teams and to communicate within and outside of their discipline, in addition to required technical skills. A collaborative multi-disciplinary service learning project referred to as Ed+gineering was implemented in a 100-level mechanical engineering course. In this collaboration, mechanical engineering students, primarily in the second semester of their freshman year or first semester of their second year, worked over the course of a semester with education students taking a foundations course to develop and deliver engineering lessons to fourth or fifth graders. Students in comparison engineering classes worked …

Open-Ended Modeling Group Projects In Introductory Statics And Dynamics Courses, Emma Treadway, J. E S Swenson, A. W. Johnson

Engineering Faculty Research

Traditionally, the types of problems that students see in their introductory statics and dynamics courses are well-structured textbook problems with a single solution [1]. These types of questions are often seen by students as being somewhat at-odds with the more “realistic” challenges that they may face in their design or lab courses. Additionally, in the pandemic-necessitated paradigm of emergency online instruction, methods of assessment beyond traditional exams have become more emphasized, both as a way of keeping students engaged by giving the material relevance and of ensuring that the work that they present is their own when so many solutions …

Precoder Design For Communication-Efficient Distributed Mimo Receivers With Controlled Peak-Average Power Ratio, Vinay A. Vaishampayan

Publications and Research

We consider the problem of communicating over a relay-assisted multiple-input multiple-output (MIMO) channel with additive noise, in which physically separated relays forward quantized information to a central decoder where the transmitted message is to be decoded. We assume that channel state information is available in the transmitter and show that the design of a rational-forcing precoder - a precoder which is matched to the quantizers used in the relays - is beneficial for reducing the symbol error probability. It turns out that for such rational-forcing precoder based systems, there is natural tradeoff between the peak to average power ratio in …

Review: Factors Affecting Composite Laminates Against Lightning Strikes, Aaryan Manoj Nair

Publications and Research

Lightning strike protection (LSP) have recently been a newly developing field particularly with the emergence of graphene thin film integration into carbon fiber composite structures. This technology has a widespread application in airplanes, wind turbines, and other instruments which are susceptible to frequent lightning strikes. Electrical discharge of the instrument in a safe manner is vital for the safety of the passengers (in the case of flights) as well as the integrity of the aircraft structures because of their specific mechanical and structural properties, which are essential for their functioning. The purpose of the study is to fabricate graphene thin …

Can Laboratory Results From New Methods Of Measuring Proppant Conductivity Be Used To Better Model Hydraulic Fractures In Reservoir Simulation?, Kofi Dabo

Graduate Theses & Non-Theses

Proppants are a key part of hydraulic fracturing, a technique in oil production that allows the production of hydrocarbons from low permeability reservoirs. The hydraulic fracturing process intends to create new fractures in the rock as well as increase the size, extent, and connectivity of existing fractures. The American Petroleum Institute (API) developed two testing procedures for measuring conductivity of proppants in a laboratory setting, namely; the Short-Term Proppant Conductivity Testing Procedure (API PR 61, 1989) and Long-Term Proppant Conductivity Testing Method (API PR 19D, 2008). However, testing methods produced inconsistent results, with a significant coefficient of variance of ±80% …

Adapting Open Pit Mine Design Fundamentals To Leverage The Advantages Of Autonomous Haulage Systems, Race Owens

Graduate Theses & Non-Theses

It is common practice, and even legally required in many jurisdictions, to design two-lane haul roads in open pit mines to three and a half times the widest dimension of the haul trucks operating on the road. In open pit gold mines with high strip ratios, the road width has a significant impact on the economics of a design. It is possible to minimize the flattening of the highwall if the road width is reduced, assuming the width used is not needed to flatten the slopes for geotechnical purposes. With the use of autonomous haulage and pull-outs, it may be …

Inhomogeneous Composite Design For High Energy Impact Resistance Through Computational Design, Physical Testing And Analysis, And Mathematical Modeling, Trenin Bayless

Graduate Theses & Non-Theses

Research in the development of impact resistant materials has been an expanding field for the better part of a hundred years. The development of a light penetration resistant and man-portable system that can resist extreme quantities of kinetic energy has been a subject of substantial study. In particular, the use of composite materials, polymers, ceramics, and metals has been critical to the development of the field. With the advent of complex computational programs for defining material properties, it has become possible to use simulations as a starting point for the development of next generation armored systems. To that end, it …

Multi-Agents For Microgrids, Salem Al-Agtash, Nisrein Al-Mutlaq, Mohamed Elabbas, Asma Alkhraibat, Mohamad Al Hashem

Computer Science and Engineering

Microgrid systems are built to integrate a generation mix of solar and wind renewable energy resources that are generally intermittent in nature. This paper presents a novel decentralized multi-agent system to securely operate microgrids in real-time while maintaining generation, load balance. Agents provide a normal operation in a grid-connected mode and a contingency operation in an islanded mode for fault handling. Fault handling is especially critical in microgrid operation to simulate possible contingencies and microgrid outages in a real-world scenario. A robust agent design has been implemented using MATLAB-Simulink and Java Agent Development Framework technologies to simulate microgrids with load …

Co-Simulation Of Electric Power Distribution And Buildings With Energyplus And Opendss, Evan S. Jones, Dan M. Ionel

Power and Energy Institute of Kentucky Presentations

Problem Formulation

• Need for accurate load modeling that incorporates human comfort into community-level demand response (DR) studies
• Achievable through co-simulation of advanced digital twins for buildings with EnergyPlus and distribution systems with OpenDSS

Erratum: Characterizing Permanent Deformation Of Alaskan Granular Base-Course Materials (Journal Of Materials In Civil Engineering Doi: 10.1061/(Asce)Mt.1943-5533.0002911), Jenny Liu, Xiong Zhang, Lin Li, Peng Li, Steve Saboundjian

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The writers would like to express their appreciation to the discusser for taking time to read this paper and provide his insightful viewpoint. The writers are in general agreement with the discusser's comments and this closure allows them to further clarify some of the statements in the original paper. Frost Heave and Change of Moisture Conditions after a Freezing Process The writers appreciate the discusser's further explanation and elaboration of results presented in Table 1 and Figs. 5 and 8. Permanent Deformation Modeling The writers agree with the discusser that the R2 values of Eqs. (2) – (4) in the …

Optical Switching Performance Of Thermally Oxidized Vanadium Dioxide With An Integrated Thin Film Heater, Andrew M. Sarangan, Gamini Ariyawansa, Ilya Vitebskiy, Igor Anisimov

Electro-Optics and Photonics Faculty Publications

Optical switching performance of vanadium dioxide produced by thermal oxidation of vanadium is presented in this paper. A 100nm thick vanadium was oxidized under controlled conditions in a quartz tube furnace to produce approximately 200nm thick VO2. The substrate was appropriately coated on the front and back side to reduce reflection in the cold state, and an integrated thin film heater was fabricated to allow in-situ thermal cycling. Electrical measurements show a greater than three orders of magnitude change in resistivity during the phase transition. Optical measurements exhibit 70% transparency at 1500nm and about 15dB extinction across a wide spectral …

Response Modification And Seismic Protection Of Yielding Structures Equipped With Inerters And Hysteretic Dampers, Gholamreza Moghimi

Civil and Environmental Engineering Theses and Dissertations

This study investigates the seismic response of structures with sustainable, long-stroke response modification devices. The main thrust of the dissertation is the investigation of the seismic response of yielding structures equipped with supplemental rotational inertia, or inerters. The last chapter of this dissertation investigates the seismic response of multistory yielding steel structures equipped with pressurized sand dampers.

Inerters are mechanical devices with resisting force proportional to the relative acceleration of their end nodes. This class of response modification devices complements the traditional fluid viscous damping devices with resisting force proportional to the relative velocity at their end-nodes. Mass-amplification is the …

Anisotropic Plasticity Modeling Of Thin Sheets And Its Application To Micro Channel Forming Of Steel Foils, Jie Sheng

Mechanical Engineering Research Theses and Dissertations

Thin sheet metals and ultrathin metal foils produced by industrial rolling processes are textured polycrystalline materials and their mechanical behaviors may depend strongly on the orientation of applied loading. Consideration of such plastic anisotropy in advanced modeling of these materials is of the paramount importance in designing optimal manufacturing processes for automotive and other applications using finite element methods. This research addresses several critical issues in anisotropic plasticity modeling and its applications in analyzing micro channel forming of ultrathin stainless-steel foils. An experimental study has first been carried out on the accuracy and sensitivity of measuring the plastic strain ratios …

Evaluation Of Liquid Deicing Materials For Winter Maintenance Applications, Erin Lammers-Staats

Kentucky Transportation Center Research Report

Winter weather can often pose difficulties for transportation agencies as they work to clear roads of snow and ice quickly so that motorists can travel safely and efficiently. Kentucky has made efforts to maximize efficiency within its winter maintenance program by focusing on optimized equipment usage and personnel time management. In this study, KYTC evaluated anti-icers and how their performance compared to the current performance of brine and calcium chloride mixture. New brine additives claim to offer better results, but there is very little guidance about how to systematically evaluate new anti-icers. Researchers were tasked with developing a testing methodology …

Home Energy Management System For Coordinated Pv And Hvac Controls Based On Ai Forecasting, Huangjie Gong, Rosemary E. Alden, Dan M. Ionel

Power and Energy Institute of Kentucky Presentations

Introduction

• This HEMS serves to transform HVAC system demand into a schedulable load bank or “dispatchable load” through controls based on day ahead forecasts
• Within this poster, a complete structure from data acquisition to day-ahead load scheduling is proposed
• For the purpose of study, measured data is used in place of forecasts to showcase best case results.

Safety Of Vulnerable Road Users (Vru's) In Light-Rail Transit (Lrt) Environment, Samir Ahmed, Rifat Bulut

Data

Light-rail transit (LRT), which includes modern streetcars, trolleys, and heritage trolleys, is one of the fastest growing modes of public transportation in the United States. To reduce the cost and complexity of construction, most LRT systems have their tracks placed on city streets, in medians, or in separate at-grade rights-of-way with at-grade crossings. Operating light-rail vehicles (LRVs) along these alignments introduces new conflicts and increases the risk of collisions with vulnerable road users (VRUs) including pedestrians, bicyclists, and electric scooter riders. This study has two main objectives: (1) to review and evaluate the existing body of knowledge and the state …

Safety Of Vulnerable Road Users (Vru's) In Light-Rail Transit (Lrt) Environment, Samir Ahmed, Rifat Bulut

Publications

Light-rail transit (LRT), which includes modern streetcars, trolleys, and heritage trolleys, is one of the fastest growing modes of public transportation in the United States. To reduce the cost and complexity of construction, most LRT systems have their tracks placed on city streets, in medians, or in separate at-grade rights-of-way with at-grade crossings. Operating light-rail vehicles (LRVs) along these alignments introduces new conflicts and increases the risk of collisions with vulnerable road users (VRUs) including pedestrians, bicyclists, and electric scooter riders. This study has two main objectives: (1) to review and evaluate the existing body of knowledge and the state …

Western Kentucky University Stormwater Utility Survey 2021, Warren Campbell, Jerry Bradshaw

SEAS Faculty Publications

No abstract provided.

Handwriting Correction System Using Wearable Sleeve With Optimal Tactor Configuration, Dhanya Nair, Grant Stankaitis, Sean Duback, Robert Geoffrion, Justin B. Jackson

Engineering Faculty Articles and Research

Handwriting remains an elusive skill with practice worksheets being the common method of learning. Since these worksheets provide only visual feedback and no quantitative feedback, it can often be a challenge to improve. For children with learning disabilities, learning handwriting skills is one of the most difficult tasks. We propose a handwriting training system that uses off-the-shelf webcam, a pen tracking software and a haptic sleeve which provides active feedback to the user based on their deviation from the original pattern. The sleeve has 4 individual motors that vibrate at different intensities based on the direction (right, left, up or …

Scalability Of The Size Of Patterns Drawn Using Tactile Hand Guidance, Dhanya Nair

Engineering Faculty Articles and Research

Haptic feedback for handwriting training has been extensively studied, but with primary focus on kinematic feedback. We provide vibrotactile feedback through a wrist worn sleeve to guide the user to recreate unknown patterns and study the impact of vibrational duration (1, 2, 3 seconds) on pattern scaling. User traces a line at 90° angles, while attempting to maintain a constant speed, in the direction of the motor activated till a different motor activation is perceived. Shape and size are two features of good letter formation. Study performed on three subjects showed the ability to utilize four vibrotactile motors to guide …