Engineering Commons^™

The Digitization Of Court Processes In African Regional And Subregional Judicial Institutions, Frederic Drabo

Walden Dissertations and Doctoral Studies

Despite information technology (IT) officers’ multiple efforts to develop reliable and efficient electronic justice (e-justice) systems, digitizing court processes still presents several quality challenges associated with IT infrastructure and literacy issues. Grounded in the principles of total quality management, the purpose of this qualitative multiple case study was to identify strategies and best practices IT officers in African regional economic communities (REC) use for digitizing regional and subregional court processes to improve African e-justice systems. The participants included four IT officers working as assistant computer system analysts (ACSA), computer system analysts (CSA), and heads of IT (HIT) in regional and …

Strategies For Catalyzing Clinicians’ Support Of Telemedicine Programs In Rural Communities, Jonathan Liwag

Walden Dissertations and Doctoral Studies

Clinicians’ failure to accept contemporary technology has been a critical barrier to telemedicine program adoption. Staff technical challenges and resistance to change can affect technology return on investment, which concerns telemedicine program leaders. Grounded in Davis’s technology acceptance model, the purpose of this qualitative, descriptive single case study was to explore strategies used by program leaders in the Marianas Islands who successfully gained clinicians’ acceptance of contemporary technology. The participants were 5 program leaders recommended by their institution because of their leadership role and telemedicine technologies experience. Data were collected from 4 face-to-face and 1 audio teleconference interview with the …

Design And Deployment Of A Mobile Learning Cloud Network To Facilitate Open Educational Resources For Asynchronous Learning, Joselito Christian Paulus M. Villanueva, Mark Anthony V. Melendres, Catherine Genevieve B. Lagunzad, Nathaniel Joseph C. Libatique

Biology Faculty Publications

This paper describes the design and deployment of a mobile cloud network that facilitates open educational resource content distribution. The setup utilized clustered single board computers as content, communication and monitoring servers. It was installed in a Public High School where stakeholders, using their mobile devices, were given access to preloaded content via wireless local area network. Initial tests of the mobile cloud showed good network performance. Teachers were randomly selected to evaluate the content validity and delivery of the OER content. Results show that the quality of the network’s OER content is very satisfactory. This implementation shows the advantage …

Simulating Ejecta Blown Off The Lunar Surface Due To Landing Spacecraft Using The Mercury N-Body Integrator, Isabel Rivera

Electronic Theses and Dissertations, 2020-2023

The experiences of the Apollo lunar landings revealed the danger lunar dust can pose to surrounding hardware, outposts, and orbiting spacecraft. Future lunar missions such as the Artemis program will require more information about the trajectories of ejecta blown by landers to protect orbiting spacecraft such as the Lunar Gateway. In this paper, we simulate lunar lander ejecta trajectories using the Mercury N-body integrator. We placed cones of test particles on the Moon at the North Pole, South Pole, and Equator with various ejection speeds and angles. The results show that particles ejected at speeds near the Moon's escape velocity …

Seismic Soil-Structure Interaction Effects In Tall Buildings Considering Nonlinear-Inelastic Behaviors, Jaime Mercado

Electronic Theses and Dissertations, 2020-2023

Soil-structure interaction (SSI) effects are relevant for the seismic analysis of tall buildings on shallow foundations since the dynamic behavior of structures is highly affected by the interaction between the superstructure and supporting soils. As part of earthquake-resistant designs of buildings, considering SSI effects in the analysis provides more realistic estimates of its performance during a seismic event, particularly when both the structure and soil undergo large demands that can compromise serviceability. Oversimplifications of structural or soil modeling in the analysis introduces variability and biases in the computed seismic response. The main goal of this dissertation is to investigate the …

Understanding Forearm Muscle Coordination In Children, Miguel Gonzalez

Electronic Theses and Dissertations, 2020-2023

A combination of surface electromyography (EMG) and pattern recognition algorithms have led to improvements in the functionality of upper limb prosthetics. This method of control relies on user's ability to repeatedly generate consistent muscle contractions. Research in EMG based control of prosthesis has mainly utilized adult subjects who have fully developed neuromuscular control. Little is known about children's ability to generate consistent EMG signals necessary to control artificial limbs with multiple degrees of freedom. To address this gap, two experiments were designed to validate and benchmark an experimental protocol that quantifies the ability to coordinate forearm muscle contractions in able-bodied …

Solidification Cracking In Binary Al-Cu Alloys Additively Manufactured Through Laser Powder Bed Fusion, Keegan Muller

Electronic Theses and Dissertations, 2020-2023

Laser Powder Bed Fusion (LPBF) is an additive manufacturing technique with growing relevance in industry. However, alloys with a high susceptibility to micro-cracking during solidification cannot be feasibly manufactured through LPBF, such as in selected high-strength Al-alloys. The cracking susceptibility (CS) of Al-alloys varies with composition, so modeling CS with respect to composition is crucial in designing compatible alloys for LPBF. In a theoretical modeling of solidification cracking based on the Scheil equation, the relative CS is taken as the maximum value of |dT/d(fs^1/2)| when solidification is near completion. However, experimental observations of the crack density in Al-alloys suggest that …

Optimizing Peer Selection Among Internet Service Providers (Isps), Shahzeb Mustafa

Electronic Theses and Dissertations, 2020-2023

Connections among Internet Service Providers (ISPs) form the backbone of the Internet. This enables communications across the globe. ISPs are represented as Autonomous Systems (ASes) in the global Internet and inter-ISP traffic exchange takes place via inter-AS links, which are formed based on inter-ISP connections and agreements. In addition to customer-provider agreements, a crucial type of inter-ISP agreement is peering. ISP administrators use various platforms like AP-NIC and NANOG networking events for establishing new peering connections in accordance with their business and technical needs. Such methods are often inefficient and slow, potentially resulting in missed opportunities or sub-optimal routes. The …

Neural Signatures Of Human Perception Of Effort And Comfort In Isometric Arm Force Exertions By Males, Raul Fernandez Sumano

Electronic Theses and Dissertations, 2020-2023

Understanding the brain's electrical activity provides objective evidence of different psychophysical phenomena related to manual handling tasks. The primary objective of this research was to assess the neural signatures of human physical efforts and perceived comfort in isometric arm exertions. Two experiments were conducted with male participants (n=20) who applied isometric forces at 1) different levels of exertion and 2) different levels of physical comfort. EEG signals, the rate of perceived exertion (RPE), and the rate of perceived physical comfort (RPC) have been recorded. The results showed statistically significant differences in EEG's power spectral density (PSD) at different brain regions …

The Critical Role Of Dynamic Surface Tension Of Surfactants On The Impact Dynamics Of Water Droplets, Amir Esmaeili, Reza Mohammadi

Graduate Research Posters

Due to their time-dependent surface tension, the addition of surface-active agents or surfactants to water for specific applications has made controlling the impact dynamics of these droplets a complex phenomenon. This work investigates the influence of the molecular weight, concentration, and ionic nature of the surfactants as well as the substrate surface characteristics on the impact dynamics of surfactant-laden droplets using a high-speed camera at 10000 frames per second. Sodium dodecyl sulfate, hexadecyltrimethylammonium bromide, and n-decanoyl-n-methylglucamine were used as anionic, cationic, and nonionic surfactants, respectively. We used hydrophilic glass slides, hydrophobic polytetrafluoroethylene, and superhydrophobic alkyl ketene dimer (AKD) as substrates. …

Natural Gas Conversion To Value-Added Chemicals By Microwave Catalytic Processes, Brandon Robinson

Graduate Theses, Dissertations, and Problem Reports (ETD)

Ethane is the second-largest component in natural gas and is typically separated out to minimize condensation in the pipelines. The technical difficulties and cost associated with the transportation and the storage of ethane have led companies to start burning natural gas to produce power or flaring which attributes to the global CO₂ emission problem. The conversion of ethane to higher-value liquid products is of increasing importance so that the natural gas can be safely utilized and cost-effectively transported. Existing commercial technologies used to convert ethane to liquid chemical products are typically based on the indirect syngas route, such as …

Distributed Cross-Community Collaboration For The Cloud-Based Energy Management Service, Yu-Wen Chen, J. Morris Chang

Publications and Research

Customers’ participation is a critical factor for inte-grating the distributed energy resources via demand response and demand-side management programs, especially when customers become prosumers. Incentives need to be delivered by the energy management service to attract prosumers to operate their distributed energy resources and electricity loads grid-friendly actively. The cloud-based energy management service enables virtual trading for customers within the same community to minimize cost and smooth the fluctuation. With the potential fast-growing number of service providers and customers, the needs exist for efficiently collaborating across multiple service providers and customers. This paper proposes the distributed cross-community collaboration (XCC) for …

Toward An Interactive, Patient-Specific, Vr-Based Obstetrics Simulator, Michel A. Audette, Marco Parente, Dulce Oliveira, Sreekanth Arikatla, Alfred Abuhamad, Rumit Singh Kakar, Mark Scerbo, Lucia Tabacu, John Conery, Christopher Macgowan, Renato Natal Jorge

Electrical & Computer Engineering Faculty Publications

This paper presents a nascent collaborative effort to achieve a Virtual Reality (VR)-based, real-time, haptics-driven patient-specific obstetrics simulator. The high-level architecture and preliminary results are presented here; the latter are based on offline birthing simulation developed by team in conjunction with open-source visualization tools. The cornerstones of this simulator will be high-fidelity generic offline birthing simulation, an anatomy-to-image nonrigid registration pipeline exploiting fetal MRI, the open-source interactive medical simulation toolkit IMSTK augmented by high-throughput deep learning-based soft tissue deformation, open-source musculoskeletal dynamics simulation platform SimTk for representing fetal motion. The initial emphasis will be on shoulder dystocia. The two main …

Electroosmotic Flow Of Viscoelastic Fluid Through A Constriction Microchannel, Jianyu Ji, Shizhi Qian, Zhaohui Liu

Mechanical & Aerospace Engineering Faculty Publications

Electroosmotic flow (EOF) has been widely used in various biochemical microfluidic applications, many of which use viscoelastic non-Newtonian fluid. This study numerically investigates the EOF of viscoelastic fluid through a 10:1 constriction microfluidic channel connecting two reservoirs on either side. The flow is modelled by the Oldroyd-B (OB) model coupled with the Poisson–Boltzmann model. EOF of polyacrylamide (PAA) solution is studied as a function of the PAA concentration and the applied electric field. In contrast to steady EOF of Newtonian fluid, the EOF of PAA solution becomes unstable when the applied electric field (PAA concentration) exceeds a critical value for …

(Quinolin-8-Yl) Tin Synthons In Transmetalation Reactions With Transition Metals Yield Multimetallic Organometallic Molecules And Clusters, Arjun Chandra Bhowmick

Dissertations and Theses

Transition metal (Hg, Ag, Pd, Ni, Sn, Cu) complexes and clusters form from the reaction of metal salts and QSnX (Q = quinolin-8-yl; X = Q or Cl) synthons. Our original intent was the use of Q2Hg, Q2Sn, or QSnCl as an ambiphilic ligand; however, we observed an apparent redox-trans metalation reaction in most of the cases. Bimetallic Hg-Ag complexes were prepared using Q2Hg as an ambiphilic ligand. Heterobimetallic (Ni-Sn and Pd-Sn) complexes were obtained from the reaction of NiCl2 (or PdCl2) with in situ generated QSnCl. Geometry and electronic configuration of the complexes were investigated using DFT methods. The …

Appointment Scheduling System, Guzaloi Noori

Undergraduate Honors Theses

Appointment Scheduling System designed for universities so that students can schedule appointments with their university’s faculty and staff regarding academic, employment, immigration, or personal issues. The scheduling system has the ability of being embedded to the Computer Science Capstone project iAcademic, which I took part in as a front-end developer.

Designing An Integrated Stem Semester For Pre-Service Elementary Teachers, Amanda Thomas, Matt Flores, Michael Hart, Elizabeth Hasseler, Tammera Mittelstet, Danae Peterson, Amy Sokoll Bauer

Department of Teaching, Learning, and Teacher Education: Faculty Publications

Teacher educators in an undergraduate elementary teacher certification program at a large university in the United States redesigned the traditional program to integrate STEM learning across multiple courses. During this Integrated STEM Semester, typically taken during the fifth semester of the undergraduate program, pre-service teachers (PSTs) enroll in mathematics content, mathematics methods, science methods, instructional technology, and practicum courses.

Data-Driven Analysis For Integrated Transmission And Distribution Systems With High Penetration Of Distributed Energy Resources, Inalvis Alvarez-Fernandez

Electronic Theses and Dissertations, 2020-2023

With the high penetration of inverter-based distributed energy resources (DERs), network situational awareness is a challenge for both transmission and distribution (T&D) system operators and planners. It is becoming increasingly important to equip transmission planners with the visibility of DER dynamic performance in distribution systems. Not having visibility of the disconnection of DERs with the occurrence of transmission events, could result in an erroneous view of the stability of bulk power system. The aggregated distributed energy resource (DER_A) model is able to model the aggregated dynamic response of inverter-based DERs in distribution circuits. The parameterization of DER_A model requires extensive …

Atomically Thin Platinum-Based Dichalcogenide Materials For Multifunctional Photo-Sensitive Applications, Mashiyat Sumaiya Shawkat

Electronic Theses and Dissertations, 2020-2023

Two-dimensional (2D) transition metal dichalcogenides (TMDs) are a distinct class of atomically thin materials assembled by weak van der Waals bonding. They exhibit 2D layer number-dependent bandgap tunability promising exciting applications in electronics and optoelectronics. Among them, there is a surge of interest in Platinum-based dichalcogenides (e.g., PtSe2 and PtTe2). 2D PtSe2 has a theoretically predicted carrier mobility of > 1000 cm2/(Vs), at room temperature, which is higher than that of most 2D TMDs. Additionally, 2D PtSe2 exhibits a semiconducting to metallic transition with an increasing number of layers. 2D PtTe2 is highly metallic in its few- layer form and exhibits …

Improving Performance And Flexibility Of Fabric-Attached Memory Systems, Vamsee Reddy Kommareddy

Electronic Theses and Dissertations, 2020-2023

As demands for memory-intensive applications continue to grow, the memory capacity of each computing node is expected to grow at a similar pace. In high-performance computing (HPC) systems, the memory capacity per compute node is decided upon the most demanding application that would likely run on such a system, and hence the average capacity per node in future HPC systems is expected to grow significantly. However, diverse applications run on HPC systems with different memory requirements and memory utilization can fluctuate widely from one application to another. Since memory modules are private for a corresponding computing node, a large percentage …

Factors That Affect The Successful Implementation Of Quality Management Systems In Healthcare, Mustafa Rawshdeh

Electronic Theses and Dissertations, 2020-2023

Modern Organizations must be high performing to sustain and grow their operations. This is particularly true for healthcare organizations as they have complex and sensitive operations. One way to improve organizational performance is to adopt Quality Management Systems (QMSs). QMSs organize and improve the effectiveness of all processes to meet stakeholder requirements and achieve organizational performance improvements in alignment with strategic goals. However, the value of QMSs is dependent on successful implementation, which is reportedly quite challenging. This doctoral research examines the factors that affect the successful implementation of QMSs in healthcare. First, a systematic analysis of the published literature …

Mechanics Of Low Dimensional Biomimetic Scale Metamaterials, Hossein Ebrahimi

Electronic Theses and Dissertations, 2020-2023

Combination of topology and material could play an important role in giving rise to nontraditional behavior in mechanical structures and is a typical strategy in nature. Topology is concerned with the geometrical and spatial properties of the objects, which are preserved under continues mechanical deformation of the object such as stretching, bending, twisting, etc. In this work, we focus on structures based on fish scale inspired surface topology. The utilized idea for surface topology is a bioinspired design on the substrate of biological scale-covered systems. Scales are a path breaking evolutionary adaptation that accompanied vertebrate evolution for the past 500 …

Heart Rate Variability In Adults During 24-Hours With A Focus On Sleep Period, Ankur Ravikanth

Honors Undergraduate Theses

The objective of this study is to investigate heart rate variability (HRV) over a period of 24 hours with special focus on patterns during the sleep period. Comparisons were made between sleep and the full 24-hour data. The Polar M430 watch was used to record heart rate (HR) data for about 24 hours, and the subject kept a journal of the activities they performed throughout the day. The data was visualized as heart rate in beats per minute (BPM) as a function of time. To check the accuracy of the Polar watch, a 7-minute recording of HR from the watch …

Experimental Study Of A Liquid Fuel Bluff Body Flame At Elevated Pressures, Karam Paul

Honors Undergraduate Theses

The purpose of this research was to operate a bluff body flame holder with the objective of stabilizing a flame at elevated pressures over a range of equivalence ratios. The ability to have a ground-based test rig capable of maintaining stable flames at high pressures and temperatures is critical in understanding flames present in modern jet engines and gas turbine technologies. The facility was reconfigured multiple times and the resultant flame was imaged within the optical test section. A converging nozzle was utilized to choke the flow and vary the operating pressures up to 5 atm. By regulating mass flow …

Electromyographic And Mechanomyogrpahic Signal Changes With Fatigue In Adults, Rehana Koilpillai

Honors Undergraduate Theses

Surface electromyography (sEMG) and mechanomyography (MMG) are well-studied signals that can reveal information about the physiological behavior of muscles during contraction. The purpose of this study was to quantify, characterize, and analyze the electrical and mechanical muscle responses to submaximal, isometric contractions in the rectus femoris in adults. Previous studies have investigated the use of EMG to monitor muscle fatigue. However, more information appears to be needed about the use of MMG to measure muscle fatigue during submaximal isometric contraction in the rectus femoris. In this study, the utility of MMG as a measure of muscle fatigue or muscle state …

Flow Field Dynamics As A Result Of Perforated Plates, Hector Perez

Honors Undergraduate Theses

Detonation to Deflagration Transition (DDT) is the process of accelerating a laminar flame to supersonic speeds to cause a detonation. A method used to reach Chapman-Jouguet (CJ) detonation velocities is the induction of turbulence to increase the surface area of the flame front, increasing the consumption rate of unburned gases and the propagation speed of the flame. Perforated plates helped achieve flame acceleration in previous studies to induce turbulence when the flame front interacts with the turbulator; previous work also accomplished detonation speeds with perforated plates. This work aims to visualize the flame front and perforated plate interaction and analyze …

Motor Control System For Near-Resonance High-Cycle Fatigue Testing, Samer K. Armaly

Honors Undergraduate Theses

This research project develops a low-cost high-cycle fatigue (HCF) testing system comprised of an AC motor, variable frequency drive (VFD), eccentric cam, and feedback controller. The system acts as a forced harmonic oscillator leveraging mechanical resonance to vibrate a specimen at a frequency required to induce the testing's strain amplitudes.

This system depends highly on the material being tested. As such, the controller incorporates material characteristics. A frequency sweep measures the strain amplitude to characterize the specimen. Additionally, other measurements such as acceleration can be used as a proxy control variables for strain. A function converts the control variable to …

Biofilm And Cell Adhesion Strength On Dental Implant Surfaces Via The Laser Spallation Technique, James D. Boyd, Arnold J. Stromberg, Craig S. Miller, Martha E. Grady

Statistics Faculty Publications

OBJECTIVE: The aims of this study are to quantify the adhesion strength differential between an oral bacterial biofilm and an osteoblast-like cell monolayer to a dental implant-simulant surface and develop a metric that quantifies the biocompatible effect of implant surfaces on bacterial and cell adhesion.

METHODS: High-amplitude short-duration stress waves generated by laser pulse absorption are used to spall bacteria and cells from titanium substrates. By carefully controlling laser fluence and calibration of laser fluence with applied stress, the adhesion difference between Streptococcus mutans biofilms and MG 63 osteoblast-like cell monolayers on smooth and rough titanium substrates is obtained. The …

Cross Approximation Methods For Integral Equation Matrices With Complex Structure, Jordon N. Blackburn

Theses and Dissertations--Electrical and Computer Engineering

Electrical and computer engineers rely on electromagnetic field (EM) theory to formulate and design systems that utilize information or energy obtained from a signal. Over time these systems have been increased in scale and complexity and adapted to handle a wider array of problems. This has motivated substantial developments in computational sciences including the area of computational electromagnetics (CEM).The focus of CEM is the simulation of electromagnetic fields. At the University of Kentucky, the CEM group has developed several modeling tools that are based on the application of approximation theory to integral equations. This allows the physical problem to be …

'Let Me See What I Could Do': Students' Epistemic Affect When Solving Open-Ended, Real-World Problems, J. Swenson, Emma Treadway, K. Beranger, A. Johnson

Engineering Faculty Research

This full research paper examines students’ epistemic affect, or their feelings about and within the doing of engineering, when encountering ill-defined problems in two of their first engineering science courses. Ill-defined problems are what students will encounter as professional engineers, but engineering students typically get little practice in their coursework at solving these types of problems. As students explained how they worked their way through the ill-defined and open-ended problems, we found evidence of both positive and negative feelings that arose, as well as descriptions of affective transitions, or shifts from one affect to another. Some of these transitions show …