Engineering Commons^™

Lignin Derived Hydrophobic Deep Eutectic Solvents As Sustainable Extractants, Yuxuan Zhang, Qi Qiao, Usman Lame Abbas, Jun Liu, Yi Zheng, Christopher Jones, Qing Shao, Jian Shi

Markey Cancer Center Faculty Publications

Solvent innovation has become a central task for improving the sustainability of chemical processes1. Deep eutectic solvents (DESs) emerge as environmentally friendly alternatives to toxic and volatile organic solvents. One appealing aspect for DESs is that they can be synthesized using naturally occurring compounds from biomass. Herein, we prepared novel hydrophobic DESs based on lignin derivatives and characterized their physicochemical properties including density, viscosity, and thermal behavior. The results showed that five lignin-derived hydrophobic DESs made from menthol, thymol, and 2,6-dimethoxyphenol were promising as green solvents due to their low viscosities and environmentally friendly constituents. To evaluate the potential application …

Clutch Analysis And Design For The Wildcat Pulling Team Quarter Scale Tractor Drivetrain, Lauren Doyle

Lewis Honors College Thesis Collection

The University of Kentucky (UK) Wildcat Pulling Team competes in the annual ASABE International Quarter Scale Tractor Student Design Competition. In 2022 the team placed 3rd overall in the competition, missing 1st place by 23 points. The loss in points was due to the clutch subassembly having issues related to maneuverability, manufacturability, and serviceability. The goal of this project was to redesign the 2022 tractor’s drivetrain for the new 2023 competition tractor. Background research was conducted on three types of clutches: manual, electric, and centrifugal. The electric clutch and centrifugal clutch with manual override were tested to determine their viability …

Advanced Microstructural Characterization Of Functionally Graded Dental Ceramic Material For Materials-Informed Finishing, Angani Vigneswaran

Theses and Dissertations--Manufacturing Systems Engineering

Yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) has gained popularity as the choice of material for dental prosthetics. Ivoclar Vivadent’s IPS e.max ZirCAD Prime dental ceramic incorporates a unique gradient technology that varies the yttria content over the thickness of the material. The top layer is composed of 5Y-TZP which is desired for its optical properties while the bottom layer is composed of a much stronger 3Y-TZP. In between the two layers, 5Y-TZP and 3Y-TZP are mixed to form a transition layer. Varying the amount of yttria allows for more esthetically pleasing translucency in the visible areas of the restoration without compromising …

Evaluating The Sustainability Of Paper And Plastic Substitute Material Limex, E.-Lexus Thornton, Avery Hartley, Daniel Caudill, Martin Gamesu, Julius M. Schoop, Fazleena Badurdeen

Mechanical Engineering Faculty Publications

With the increasing decline in the environment and natural resources it is important to find new ways in which manufacturing can increase the sustainability of the world. This study seeks to compare LimeX, a state-of-the-art paper and plastic alternative primarily made of limestone, with conventional paper and plastic materials. For a better understanding of LimeX as a material, a brief investigation of the mechanical and chemical properties will be performed through experimentation and analysis. In addition, this paper aims to evaluate the sustainability of LimeX through the analysis of metrics relating to the triple bottom line (environmental impacts, economic impacts …

Statistical Tolerance Regions For Flexible Modeling Paradigms, Yafan Guo

Theses and Dissertations--Statistics

Tolerance intervals in a regression setting allow the user to quantify, with a specified degree of confidence, bounds for a specified proportion of the sampled population when conditioned on a set of covariate values. While methods are available for tolerance intervals in fully-parametric regression settings, the construction of tolerance intervals for semiparametric regression models has been treated in a limited capacity. The first project fills this gap and develops likelihood-based approaches for the construction of pointwise one-sided and two-sided tolerance intervals for semiparametric regression models. A numerical approach is also presented for constructing simultaneous tolerance intervals. An appealing facet of …

Recovery Of Valuable Metals From Electronic Waste Using A Novel Ammonia-Based Hydrometallurgical Process, Peijia Lin

Theses and Dissertations--Mining Engineering

The growing quantity of waste electrical and electronic equipment (WEEE), also known as electronic waste (E-waste), has been an area of growing public concern. The abundance of valuable metals contained in waste printed circuit boards (WPCBs) has made it a promising secondary resource, especially for Cu and Au. Although the recovery of metals from WPCBs via hydrometallurgical routes has been studied extensively over the past 20 years, most of the research has been limited in the laboratory. In current hydrometallurgical processes, strong acids and expensive oxidizers are often used to ensure a high recovery of metals without considering the sustainability …

Operationalizing A Culture For Successful Lean Transformations: A Framework And Model-Based Tools, Amir Najarzadeh Dr.

Theses and Dissertations--Manufacturing Systems Engineering

Lean manufacturing has been embraced by many companies as a business model to promote operational excellence. However, a high percentage of lean implementation attempts have failed; many organizations have not been able to sustain continuous improvements to achieve lean transformations. This failure is often attributed to the sole focus on the hard-side (tools) of lean, at the expense of the soft side (culture). The majority of research exploring the cultural dimensions of lean either aims to increase awareness about culture or addresses it only in a cursory manner. To bridge this gap this study aims to identify and assess the …

Decarbonization Analysis For Thermal Generation And Regionally Integrated Large-Scale Renewables Based On Minutely Optimal Dispatch With A Kentucky Case Study, Donovin Lewis, Aron Patrick, Evan S. Jones, Rosemary E. Alden, Abdullah Al Hadi, Malcolm D. Mcculloch, Dan Ionel

Power and Energy Institute of Kentucky Faculty Publications

Decarbonization of existing electricity generation portfolios with large-scale renewable resources, such as wind and solar photo-voltaic (PV) facilities, is important for a transition to a sustainable energy future. This paper proposes an ultra-fast optimization method for economic dispatch of firm thermal generation using high granularity, one minute resolution load, wind, and solar PV data to more accurately capture the effects of variable renewable energy (VRE). Load-generation imbalance and operational cost are minimized in a multi-objective clustered economic dispatch problem with various generation portfolios, realistic generator flexibility, and increasing levels of VRE integration. The economic feasibility of thermal dispatch scenarios is …

A Process Intensification Approach To Improve Volatile Fatty Acids Production, Extraction, And Valorization, Can Liu

Theses and Dissertations--Biosystems and Agricultural Engineering

Anaerobic digestion (AD) is a widely used biowaste conversion method. Recent studies have explored arrested methanogenesis as an alternative approach to leverage existing AD facilities and produce volatile fatty acids (VFAs) instead of biogas. VFAs have been recognized as precursors for a range of value-added chemicals and bioproducts. Arrested methanogenesis involves inducing acidic fermentation by halting the AD process before methanogenesis. It has been found that higher organic loading and thermophilic conditions enhance VFA accumulation and stabilize the acidic fermentation (AF) system.

Brewer's spent grain (BSG), a significant by-product of the brewing industry, was employed as the feedstock for VFA …

Personalized Point Of Interest Recommendations With Privacy-Preserving Techniques, Longyin Cui

Theses and Dissertations--Computer Science

Location-based services (LBS) have become increasingly popular, with millions of people using mobile devices to access information about nearby points of interest (POIs). Personalized POI recommender systems have been developed to assist users in discovering and navigating these POIs. However, these systems typically require large amounts of user data, including location history and preferences, to provide personalized recommendations.

The collection and use of such data can pose significant privacy concerns. This dissertation proposes a privacy-preserving approach to POI recommendations that address these privacy concerns. The proposed approach uses clustering, tabular generative adversarial networks, and differential privacy to generate synthetic user …

Quality Control Methods Through Pre-Determination Of Fields For Usrap Projects, Zachary Heath

Theses and Dissertations--Civil Engineering

The United States Road Assessment Program (usRAP) was designed to rate highways for their ability to protect road users and to make recommendations to engineers and policy makers for investments to enhance road safety. The program is heavily dependent on local road data or characteristics. Pre-populating usRAP requires coders to evaluate sixty-six attributes at 100-meter intervals along a subject highway. In this thesis, methods for obtaining and assuring the quality of some of the usRAP data elements are proposed. Kentucky Transportation Cabinet Highway Information System (HIS) data are used as “ground truth” for roadway grade and curvature. Methods of using …

Historical And Forecasted Kentucky Specific Slope Stability Analyses Using Remotely Retrieved Hydrologic And Geomorphologic Data, Daniel M. Francis

Theses and Dissertations--Civil Engineering

Hazard analyses of rainfall-induced landslides have typically been observed to experience a lack of inclusion of measurements of soil moisture within a given soil layer at a site of interest. Soil moisture is a hydromechanical variable capable of both strength gains and reductions within soil systems. However, in situ monitoring of soil moisture at every site of interest is an unfeasible goal. Therefore, spatiotemporal estimates of soil moisture that are representative of in-situ conditions are required for use in subsequent landslide hazard analyses.

This study brings together various techniques for the acquisition, modeling, and forecasting of spatiotemporal retrievals of soil …

Clustering States To Improve The Strategic Highway Safety Plan, Victoria Cambron

Theses and Dissertations--Civil Engineering

Each update to a Strategic Highway Safety Plan (SHSP) can require a large amount of time, resources, and funding. From the requirements in U.S.C.148(a)(13)(E-F), in the SHSP update process states must consider the results of other transportation planning processes and develop a list of strategies to reduce or eliminate fatal and serious injury crashes (United States, 2023). To fulfill these requirements more efficiently and to gain the largest amount of benefit from said research, this thesis asks the question: how do we select other state transportation plans to study for ideas on improving our own SHSP? In this thesis, a …

Value Propositions, Adoption Factors, And Implementation Considerations: Building A Path Towards Construction Innovation, Makram Bou Bou Hatoum

Theses and Dissertations--Civil Engineering

The construction industry has been influenced by a wave of technological advancements and trends that were introduced by the fourth industrial revolution or Industry 4.0. Mapped as Construction 4.0, these technologies are disrupting the way projects are designed, planned, constructed, delivered, and operated. While existing research has predominantly focused on technology adoption and use cases across the project lifecycle, limited attention has been given to the organizational perspective and explored Construction 4.0 as a transformative vision. As such, there is a significant need for decision science research to support decision-makers in understanding the value of Construction 4.0, gaining leadership buy-in, …

Implementation Of Digital Twins For Small Water Systems, Aidan Gill

Theses and Dissertations--Civil Engineering

The main objective of this thesis is to develop a working digital twin for a small water system in central Kentucky which will serve as a general format for other similar systems in the region wishing to implement digital twins for operator support. While the benefit of having a calibrated hydraulic and water quality model is widely understood, small distribution systems tend to not have the same financial and economic means to properly support these tools. Creation of a digital twin using this methodology provides a means for operators to predict pressure, flows, chlorine residuals, and total trihalomethane (TTHM) concentrations …

Soil Moisture And Geomorphologic Data For Use In Dynamic And Forecastable Landslide Hazard Analyses In Eastern Kentucky, Daniel M. Francis, L. Sebastian Bryson

Civil Engineering Research Data

These data are the geomorphologic and land information system-based soil moisture estimates from assimilation of NASA SMAP satellite-based observations and NOAH 3.6 Land Surface Model estimates over known landslides in Eastern Kentucky. Additionally Long Short-Term Memory Recurrent Neural Network and logistic regression machine learning codes, as well as an Application programming interface code are included. Finally, in-situ data from Eastern Kentucky is included.

A Laboratory And Numerical Investigation Of The Strength Of Irregularly Shaped Pillars, Zachary Wedding

Theses and Dissertations--Mining Engineering

Underground mining operations utilize the room-and-pillar mining method that extracts the orebody and creates ‘rooms’ and leaves the remaining in-situ material as ‘pillars’ to support the overburden. Room-and-pillar mines are traditionally designed in square or rectangular-shaped pillars. This work presents laboratory experiments testing the compressive strengths of specimens modeled after square and parallelogram-shaped pillars and numerical models of square and -parallelogram-shaped pillar systems. The uniaxial compressive strength of the specimens’ shape and the observations of the extent of the specimen core post-failure were analyzed. There was insufficient evidence from the laboratory experiments to conclude that there is a difference in …

Spatiotemporal Retrievals Of Soil Moisture And Geomorphologic Data For Landslide Sites In Eastern Kentucky, Lindsey Sebastian Bryson, Daniel M. Francis

Civil Engineering Research Data

These data are the soil texture, land information system-based soil moisture estimates from assimilation of NASA SMAP satellite-based observations and NOAH 3.6 Land Surface Model estimates, artificial neural network machine learning code, and in-situ soil moisture measurements.

Classifying Multi-Generational Products For The Circular Economy, Buddhika M. Hapuwatte, Fazleena Badurdeen, I. S. Jawahir

Institute for Sustainable Manufacturing Faculty Publications

Manufacturers are increasingly interested in the circular economy (CE) and potential of circular productions. To fully utilize CE, better guidance at the design stage is needed to establish closed-loop flows and prioritize higher value retaining end-of-use (EoU) practices such as reuse and remanufacture (i.e., parts harvesting). Intergenerational commonality (IC) is a method to increase EoU parts harvesting. However, closed-loop parts harvesting potential depends on the compatible timing between design generations’ production and EoU returns curves. Therefore, in this paper, we explore an approach to make an initial assessment on where IC as a closed-loop CE strategy can produce most benefit, …

Low-Head Dams (Aka Drowning Machines) Are Deadly: An Analysis Of Liability For Landowners And States, And Recommendations For Legislation And Warning Signs, Forrest R. Hansen, Rollin H. Hotchkiss

Kentucky Journal of Equine, Agriculture, & Natural Resources Law

No abstract provided.

Circulating And Eddy Current Losses In Coreless Axial Flux Pm Machine Stators With Pcb Windings, Yaser Chulaee, Donovin Lewis, Ali Mohammadi, Greg Heins, Dean Patterson, Dan Ionel

Power and Energy Institute of Kentucky Faculty Publications

Printed circuit board (PCB) stators in coreless axial flux permanent magnet (AFPM) machines have been proposed, designed, and studied for use in multiple industries due to their design flexibility and reduction of manufacturing costs, volume, and weight compared to conventional stators. This paper investigates mechanisms and methods of approximating open circuit losses in PCB stators within example wave and spiral winding topologies for a dual rotor, single stator configuration using 3D FEA, analytical hybrid techniques and experiments. The effect of rotor magnet shape, end winding, and active conductor geometry on eddy currents is studied, and some mitigation techniques are proposed. …

Graduated Driver Licensing Program, Jeeyen Koo, Andrew Martin, Jennifer Walton

Kentucky Transportation Center Research Report

To address challenges related to teen driver safety, Kentucky adopted a simple graduated driver licensing (GDL) program in 1996 and further expanded it in 2006 by adding an intermediate licensing phase, requirements for supervised practice driving, and instituting restrictions on passenger age. Despite GDL programs having been adopted throughout the US, young drivers (ages 16 – 20) continue to be overrepresented in fatal crashes. In 2019, despite this segment making up roughly 5.3 percent of licensed drivers it accounted for 11.5 percent of fatal vehicle crashes (Kentucky recorded 732 crash fatalities, of which 73 involved young drivers). Although teen driver …

2+1 Roadway Design Guidance Update, Jeff Jasper, Jeff Wolfe, Robin Baskette, Paul Ross, Chris Van Dyke

Kentucky Transportation Center Research Report

The frequency and severity of crashes on rural two-lane roadways have increased in the US relative to other road types. This trend can be explained by the growing number of vehicles, higher speeds, narrow shoulders, and vehicle mixes. One solution for improving traffic flow and safety outcomes on rural two-lane roadways is to adopt a 2+1 design, which confers the benefits of four-lane highways but at a lower cost. Transportation agencies throughout Europe — and increasingly the US — have seen good results from 2+1 layouts. Crash data from Sweden, Germany, Finland, and Denmark reveal better safety outcomes following the …

Pedestrian And Bicycle Improvement Scoring Method For Shift–2024, Nikiforos Stamatiadis, Daria Korostina, Teng Wang, Reginald Souleyrette

Kentucky Transportation Center Research Report

State transportation agencies have limited funding to deliver multimodal transportation programs that address the needs of all users. To allocate project funding in an impartial and objective manner, many agencies have adopted data-driven scoring systems that are used to evaluate the merits of proposed capital improvement projects. The Kentucky Transportation Cabinet introduced the Strategic Highway Investment Formula for Tomorrow (SHIFT) for this purpose. Until now SHIFT, has evaluated projects based five core variables — congestion, safety, benefit-cost ratio, asset management, economic growth. To address local needs, SHIFT has also allocated points that Area Development Districts, metropolitan planning organizations, and Cabinet …

Prediction Of Blast-Induced Ground Vibrations: A Comparison Between Empirical And Artificial-Neural-Network Approaches, Luis F. Velasquez

Theses and Dissertations--Mining Engineering

Ground vibrations are a critical factor in the rock blasting process. The instantaneous load application exerted by the gas pressure during the detonation process acts on the blasthole walls creating dynamic stresses in the adjacent rock. This triggers different sorts of stress waves, mainly divided into two categories: body and surface waves. The first comprises the P and the S waves, while the second comprises Rayleigh waves. These waves spread concentrically starting at the blast location and move along the ground surface and its interior, being attenuated as they reach further distances.

In most cases, and accepting the hypothesis that …

An Acid Baking Approach To Enhance Rare Earth Element Recovery From Bituminous Coal Sources, Ahmad Nawab

Theses and Dissertations--Mining Engineering

Rare earth elements (REE) are a group of 17 elements typically classified as light and heavy rare earth elements, which play a crucial role in developing the latest technologies for energy, defense, and medical sectors. Even though REEs have been found in more than 200 minerals, only bastnaesite, monazite and xenotime are commercially exploited for REE extraction. However, the recent exponential increase in REE demand has spurred countries such as the United States into research for the extraction of REEs from secondary sources such as coal, acid mine drainage, and coal ash. Several coal sources (e.g., Fire Clay seam coal) …

Defining Sagittal Plane Gait Mechanics And Joint Loading In People With Marfan Syndrome, Justin Melan Pol

Theses and Dissertations--Biomedical Engineering

Marfan syndrome (MFS) is a genetic condition that is associated with altered muscle composition, which leads to muscle dysfunction. People with MFS exhibit high instances of lower extremity (LE) joint pain that inhibits their ability to perform activities of daily living, such as walking. Despite these detrimental impacts of MFS, there have been no attempts to characterize the effects of MFS on LE joint loading and health during walking that are associated with LE pain and dysfunction. As people with MFS exhibit a high incidence rate of osteoarthritis (OA), the need to understand the potential alterations in LE extremity mechanics …

3-Dimensional Muscle Constructs: Using Hydrogels In Order To Model The Effects Of Exercise In Disease Conditions, Mark Mchargue

Theses and Dissertations--Biomedical Engineering

Currently, there is no standard in vitro model for studying the effects of mechanical stimulation on muscle in type II diabetes. Existing models primarily utilize electrical stimulation, which does not fully recapitulate the effects of exercise. In this thesis, we create a standardized in vitro model of murine muscle that can recapitulate the benefits seen in exercise when mechanically stimulated. Moreover, we show that a type II diabetes environment has similar effects on the muscle in vitro as well as in vivo.

Multiscale And Multimodality Optical Imaging Of Brain Hemodynamics And Function, Mehrana Mohtasebi

Theses and Dissertations--Biomedical Engineering

Frequent measurement of cerebral hemodynamics is crucial for continuous assessment of brain function and health. Low-frequency oscillations (LFOs; < 0.1 Hz) have shown promise as an indicator of altered neurologic activity in the abnormal brain. Moreover, quantification of temporal correlations in LFOs across distinct brain regions enables mapping of regional neurovascular disorders. Portable diffuse optical techniques such as near-infrared spectroscopy (NIRS) and diffuse correlation spectroscopy (DCS) enable noninvasive and continuous measurements of cerebral oxygenation and cerebral blood flow (CBF), respectively. However, most NIRS/DCS systems use limited numbers of discrete light sources and detectors and thus lack combinations of high temporal/spatial resolution and large field-of-view (FOV) for brain imaging. Recent development of an innovative noncontact speckle contrast diffuse correlation tomography (scDCT) in our lab provides a low-cost and portable tool for high-density imaging of CBF distributions over large FOVs. The scDCT uses a galvo-mirror to remotely deliver coherent point near-infrared light to multiple source positions and a CMOS camera as a high-density 2-D detector array to quantify spatial fluctuations of diffuse laser speckles, resulting from movement of red blood cells. Boundary CBF data were input to a unique finite-element-method (FEM)-based reconstruction algorithm for 3-D imaging of CBF distributions. However, scDCT was hindered for extracting LFOs due to its low sampling rate. In this study, scDCT was optimized to achieve high sampling rates and fast image reconstructions by use of moving window algorithms with parallel computations (Project 1). Power spectral density (PSD) analysis was performed to investigate altered LFOs during transient cerebral ischemia in neonatal piglets. Transient cerebral ischemia caused reductions in both CBF and PSD, supporting inclusion of scDCT in the growing field of LFO analysis. One remaining limitation was the long computational time required for 3-D reconstruction, which prohibited real-time applications. To overcome this limitation, a depth-sensitive diffuse speckle contrast topography (DSCT) method was developed for analyzing scDCT data to achieve fast and high-density 2-D mapping of CBF distribution without the need of complex and time-consuming 3-D reconstructions (Project 2). New head-simulating phantoms with known optical/geometric properties were designed and fabricated to evaluate the spatial resolution and depth sensitivity of DSCT method. In-vivo experiments verified the capability of DSCT in tracking dynamic changes in CBF at different depths during CO₂ inhalation and transient cerebral ischemia in rats. In addition to preclinical studies, a low-cost, wearable, fluorescence eye loupe (FLoupe) device was invented for intraoperative visualization of brain tumor margin in the clinic (Project 3). Consistent results were observed against an expensive, large, standard fluorescence operative microscope for the guidance of tumor resection. Overall, through 3 projects this dissertation demonstrated a variety of noninvasive noncontact optical technologies (scDCT, DSCT, and FLoupe) that enabled multiscale (rodents, piglets, and humans) and …

A Wearable Fiber-Free Optical Sensor For Continuous Measurements Of Cerebral Blood Flow And Oxygenation, Xuhui Liu

Theses and Dissertations--Biomedical Engineering

Wearable technologies for continuous monitoring of cerebral hemodynamics in freely behaving subjects not only advance our understanding of cognitive processing and adaptive behavior, but also provide vital information for diagnosis and therapeutic assessment of cerebral diseases associated with hypoxia/ischemia. Wearable near-infrared diffuse optical techniques have been used at the bedside to probe deep cerebral hemodynamics, including near-infrared spectroscopy (NIRS) for cerebral oxygenation measurement and diffuse correlation spectroscopy (DCS) for cerebral blood flow (CBF) measurement, respectively. However, most systems are relatively large and expensive, and use rigid fiber-optic probes that significantly constrain subject’s movement. A novel, wearable, fiber-free diffuse speckle contrast …