Engineering Commons^™

Synchronous Raman Microspectroscopy And Laser Beam Induced Current Measurements As A Metrology Tool For Solar Cells And Optoelectronic Devices, Jeya Prakash Ganesan

Electronic Theses and Dissertations, 2020-2023

This works developed synchronous Raman microspectroscopy with laser beam induced current (LBIC) measurements to generate insights into structure-property correlations in finished solar cell modules. Raman spectroscopy is a powerful, non-destructive technique to examine phase and composition of materials where a laser beam excites characteristic vibrational modes of chemical bonds in a material. Conducting Raman spectroscopy under a microscope (i.e., Raman microspectroscopy) with confocal capabilities allows the chemical constituents to be mapped with high spatial resolution in the x, y and z directions. Simultaneously, the excitation laser from Raman can also generate photocarriers in a semiconductor. In a solar cell, these …

Machine Learning Algorithms For Forecasting The Impacts Of Connected And Automated Vehicles On Highway Construction Costs, Amirsaman Mahdavian

Electronic Theses and Dissertations, 2020-2023

A multitude of externalities affects transport efficiency and numbers of trips. Population expansion, urban development, political issues, fiscal trends, and growth in the field of connected, automated, shared, and electric (CASE) vehicles have all played prominent roles. While the market is keenly aware of the upcoming shift to the CASE vehicles, the transformation itself is reliant upon the development of technologies, customer outlook, and guidelines. The purpose of this research is to establish an overview of the possible network design problems, as well as potential consequences to vehicle automation systems by employing machine learning and system dynamics analysis. Finally, the …

Davydov-Split Aggregates Of Cyanine Dyes For Bovine Serum Albumin Detection, Yiping Ma

Electronic Theses and Dissertations, 2020-2023

The p-conjugated supramolecular aggregates have gained significant interest in recent years. The cyanine dye aggregates are particularly interesting due to their unique optical and excitonic properties, which cannot be found in individual molecules. Cyanine dyes can form different kinds of aggregates. H-aggregates are formed when dye molecules are packed in a face-to-face fashion, which gives rise to a blue-shift absorption band and strong emission quenching compared to the monomer. J-aggregates are composed of individual dye molecules in a head-to-tail stacking, which leads to a red-shift absorption band and a sharp intense emission band with a small Stoke shift compared with …

Data-Driven Diagnostics And Prognostics For Complex Systems: Methods And Applications, Junchuan Shi

Electronic Theses and Dissertations, 2020-2023

Recent advances in artificial intelligence or machine learning have the potential to significantly improve the effectiveness and efficiency of diagnostic and prognostic techniques. The objective of this research is to develop novel data-driven predictive models with machine learning and deep learning algorithms that allow one to model the degradation, detect the faults, as well as predict the remaining useful life (RUL) of complex systems, including bearings, gearboxes, and Lithium-ion (Li-ion) batteries. First, an enhanced ensemble learning algorithm is developed to improve the accuracy of RUL prediction by selecting diverse base learners and features at different degradation stages. The proposed method …

A Study Of Autorotation: Samara Seed Pods And Tethered Autogyros, Jonathan Mcconnell

Electronic Theses and Dissertations, 2020-2023

This work presents an exploration of autorotational behavior, observing naturally occurring structures to provide insight into the stability and design of autorotative mechanisms. A rotor is said to be in autorotation when, in the presence of airflow, a natural rotation generates lift to either suspend or slow the descent of a rotor. This phenomenon is observed in nature in the form of samaras, a seed pod morphology evolved in parallel by maple trees and many other organisms around the world. Simulation and experimental observation of samara vertical descent behavior provides insight into the stability of naturally evolved autorotative structures. A …

A Spatiotemporal Evaluation Of Freeway Traffic Demand In Florida During Covid-19 Pandemic, Md Istiak Jahan

Electronic Theses and Dissertations, 2020-2023

This thesis contributes to our understanding of the changes in traffic volumes on major roadway facilities in Florida due to COVID-19 pandemic from a spatiotemporal perspective. Three different models were tested in this study- a) Linear regression model, b) Spatial Autoregressive Model (SAR) and c) Spatial Error Model (SEM). For the model estimation, traffic volume data for the year 2019 and 2020 from 3,957 detectors were augmented with independent variables, such as- COVID-19 case information, socioeconomics, land-use and built environment characteristics, roadway characteristics, meteorological information, and spatial locations. Traffic volume data was analyzed separately for weekdays and holidays. SEM models …

Acute Coronary Syndrome Prediction: A Data-Driven Machine Learning Modeling Approach In Emergency Care, Joshua Oluwatobiloba Emakhu

Wayne State University Dissertations

Healthcare facilities are faced with significant challenges all year round, with patients presenting to the emergency department (ED) with different health issues. Of these challenges, heart disease seems to be an outlier. With heart disease being the primary cause of mortality and morbidity in both developed and developing countries, clinical concerns for acute coronary syndrome (ACS) are one of emergency medicine’s most common patient encounters. Of the three sub-categories of ACS, non-ST-segment elevation myocardial infarction (NSTEMI) has a long-term impact on the well-being of patients if left untreated. Previous efforts in hospital management have applied machine learning algorithms in differentiating …

Electrochemical Gelation Of Metal Chalcogenide Quantum Dots, Chathuranga Chinthana Hewa Rahinduwage

Wayne State University Dissertations

Quantum dots (QDs) are attractive because of their unique size-dependent optical and electronic properties and high surface area. They are tested in research for diverse applications, including energy conversion, catalysis, and sensing. Assembling QDs into functional solid-state devices while preserving their attractive properties is a challenge. Methods currently under the research are not effective in directly fabricating QDs onto devices, making large area assemblies, maintaining the high surface area by forming 3D porous structures, and conducting electricity for applications such as sensing. QD gels are an example of QD assemblies that consist of a 3D porous interconnected QD network. They …

Automated, Robust Radiomics Biomarker Modeling For Glioblastoma, Eric Nathan Carver

Wayne State University Dissertations

Individualized medicine is possible due to the discovery that a patient’s gene expression can serve as a bio-marker and provide prognostic clinical knowledge. The genetic revolution increased interest in the field of “-omics” which investigates differing classifications of patient characteristics to increase clinician knowledge, which directly improves patient care. Glioblastoma (GBM) is the most aggressive brain cancer and very difficult to treat, resulting in a 15 month median survival. Researchers have discovered several patient specific markers, specifically IDH1 and MGMT methylation, which energized further research for GBM patient specific markers. A relatively new subfield of ‘-omics’ is Radiomics; which aims …

An Interleaved High Step-Up Dc-Dc Converter With Coupled Inductor And Built-In Transformer For Renewable Energy Applications, Ramin Rahimi, Saeed Habibi, Mehdi Ferdowsi, Pourya Shamsi

Electrical and Computer Engineering Faculty Research & Creative Works

This paper introduces an interleaved high step-up DC-DC converter with high voltage gain, low voltage stresses on the switches, low current stresses on the components, and continuous input current with low ripple, all of which are beneficial for the renewable energy (RE) applications. The proposed converter is based on the integration of three voltage-boosting (VB) methods: coupled inductor (CI), built-in transformer (BIT), and switched-capacitor (SC) cells. The energies of the leakage inductances of the CIs and BIT are absorbed and recirculated to the output side, which further extends the voltage gain. In addition, the current-falling rates of the diodes are …

A Spline-Based Partial Element Equivalent Circuit Method For Electrostatics, Riccardo Torchio, Maximilian Nolte, Sebastian Schops, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

This contribution investigates the connection between Isogeometric Analysis (IgA) and the Partial Element Equivalent Circuit (PEEC) method for electrostatic problems. We demonstrate that using the spline-based geometry concepts from IgA allows for extracting circuit elements without an explicit meshing step. Moreover, the proposed IgA-PEEC method converges for complex geometries up to three times faster than the conventional PEEC approach and, in turn, it requires a significantly lower number of degrees of freedom to solve a problem with comparable accuracy. The resulting method is closely related to the isogeometric boundary element method. However, it uses lowest-order basis functions to allow for …

Optimal Adaptive Output Regulation Of Uncertain Nonlinear Discrete-Time Systems Using Lifelong Concurrent Learning, R. Moghadam, B. Farzanegan, S.(Sarangapani) Jagannathan, P. Natarajan

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Addresses Neural Network (NN) based Optimal Adaptive Regulation of Uncertain Nonlinear Discrete-Time Systems in Affine Form using Output Feedback Via Lifelong Concurrent Learning. First, an Adaptive NN Observer is Introduced to Estimate Both the State Vector and Control Coefficient Matrix, and its NN Weights Are Adjusted using Both Output Error and Concurrent Learning Term to Relax the Persistency Excitation (PE) Condition. Next, by Utilizing an Actor-Critic Framework for Estimating the Value Functional and Control Policy, the Critic Network Weights Are Tuned Via Both Temporal Different Error and Concurrent Learning Schemes through a Replay Buffer. the Actor NN Weights …

Tolle Lege Works Published In 2022, Mcquade Library

Bibliographies

Compiled Tolle Lege bibliography of works published by members of the Merrimack College Community in 2022. Works include journal articles, books, book chapters, conference presentations and posters, and more.

First-Year Engineering Living-Learning Communities Improve Four-Year Graduation Rates At A Small Private University, William J. Palm

Engineering, Computing & Construction Management Faculty Publications

This complete research paper assesses the long-term benefits of first-year student participation in an Engineering Living-Learning Community (ELLC) at a relatively small private university. Prior research on ELLCs has examined short-term results such as first-year student engagement, academic performance, and retention, but relatively few studies have reported data on long-term outcomes such as graduation rates and GPA at graduation. This paper reports the outcomes of four cohorts of Engineering students who entered the study university between 2013 and 2016.

Students participating in the ELLC had significantly higher 4-year graduation rates in Engineering (55.7% vs. 42%) and in STEM (64.3% vs. …

Security Issues With Network Connected Scada Systems, Chad Holm

Cybersecurity Undergraduate Research Showcase

The use of Supervisory Control and Data Acquisition (SCADA) systems has become common place and are being used in several different industries. These have evolved as the technology has progressed. The use of Internet of Things (IOT) devices makes for less human intervention to run daily operations in these industries. This can also allow hackers to gain access to these devices due to security holes that are overlooked. There have several different ways that have been exploited on SCADA networks and the goal is to recognize and secure them so hackers cannot gain access to them.

Corporate Cybersecurity In The Context Of M&A Transactions, Cameron Beck

Cybersecurity Undergraduate Research Showcase

The rapid rise of digital devices has unlocked a new dimension of innovation and prosperity in the 21st century. Computers are now an integrated and ubiquitous part of our global culture. You would be hard-pressed to walk into any given room without several computer chips humming inaudibly inside the machines that facilitate our modern world. Even lightbulbs and doorbells are connected to the Internet, capturing information from the world around them and sending that information to the Cloud. The Internet expands access to communication, international marketplaces, entertainment, professional resources, and nearly every book in the world.

Biom 7432/8432: Advanced Biomaterials (Syllabus), Gary L. Bowlin

Biomedical Engineering Syllabi Archive

Course Description: Materials used in biomedical applications in relationship to corrosion, crack propagation, creep, and related topics; tissue ingrowth into materials.

Biom 4110(Honors)/6110: The Science Of Medicine (Syllabus), Bradford D. Pendley

Biomedical Engineering Syllabi Archive

Course Description: Integration of fundamental principles from physics, chemistry, biology and mathematics, and applications of these principles to solve problems in medicine.

Reconstructing The Radio, Daniel Burzek, Otilia Popescu

OUR Journal: ODU Undergraduate Research Journal

The goal of the research presented in this paper is to examine the techniques used for the construction of early radios, specifically crystal radios. The paper begins with a brief summary of the history that led to the transition from wired to wireless communication. Next, the paper examines the components used in building a crystal radio including basic antenna design and the resonant circuit, and it also takes a close look at the point-contact rectifier, which was a catalyst in the use of radio waves for communications and allowed for even the most inexperienced person to construct their own home …

The Development Of An Inexpensive Alternative To Industry Solar Simulators, Raines A. Vanhuss

OUR Journal: ODU Undergraduate Research Journal

Solar cells are a prominent renewable energy source used in the twenty-first century. In order for the technology to grow, research lab equipment is needed to measure and characterizes these cells. This report covers solar simulator devices and proposes an alternative design solution to lessen the cost of solar cell lab equipment. Common household light sources were tested by generating I-V characteristics using an amorphous silicon solar cell. The light bulb that generated the best I-V curve was selected and then tested for the optimal distance between the light source and the solar panel. The alternative solar simulator was then …

Voluntary Control Of Breathing According To The Breathing Pattern During Listening To Music And Non-Contact Measurement Of Heart Rate And Respiration, Dibyajyoti Biswal

Theses and Dissertations--Biomedical Engineering

We investigated if listening to songs changes breathing pattern which changes autonomic responses such as heart rate (HR) and heart rate variability (HRV) or change in breathing pattern is a byproduct of listening to songs or change in breathing pattern as well as listening to songs causes changes in autonomic responses. Seven subjects (4 males and 3 females) participated in a pilot study where they listened to two types of songs and used a custom developed biofeedback program to control their breathing pattern to match the one recorded during listening to the songs.

Coherencies between EEG, breathing pattern and RR …

Thermal Testing And Simulation Of Lunar And Martian Isru-Based Materials, Andres Campbell

All Undergraduate Theses and Capstone Projects

Upon the eventual return of humans to the lunar surface, leveraging local resources to construct landing pads and other infrastructure is an essential component to minimize cost and risk. The inability to accurately model landing and launch scenarios to predict damage to lunar structures poses risks to astronaut and equipment safety. The following experiment is an investigation of using simulation software and temperature sensors to model lunar and Martian regolith simulant-based concrete exposed to thermal loads. The basis of this experiment is built upon standards defined by the American Society for Testing and Materials, the fundamental axioms of structural health …

Optimal Speed Control Of Electric Vehicles In Traffic With Wireless Charging, Amina Jemi

All Graduate Theses, Dissertations, and Other Capstone Projects

With the increase in electric vehicle use in recent years and expected increase in the future, a wireless network provides a possible option to allow vehicles with a route while maintaining an approximate net-zero energy balance under certain scenarios. In this type of network, a collection of wireless charging pads is installed under the road, and energy transfer occurs, while a vehicle with wireless charging capability is driven over the charging pads. This thesis describes a methodology and modeling to solve an optimization problem involving a speed-controlled vehicle in traffic. The methodology incorporates a receding horizon dynamic model with constraints. …

Data Supporting Effects Of Uv-C Disinfection On N95 And Kn95 Filtering Facepiece Respirator Reuse, Castine A. Bernardy, James Malley

Data Catalog

UV is a proven decontamination tool for microbial pathogens, including the SARS-CoV-2 virus. Lower log inactivation was observed on FFRs than would have been predicted by aqueous-based UV dose-response data for MS-2 bacteriophage and E. coli. Results have demonstrated that FFR materials yield varying results in terms of effective disinfection in experiments conducted on KN95 and N95 face respirators. The highest inactivation for both surrogates was observed with respirator KN95 B. The respirator yielded 3 and 2.75 log inactivation for E. coli and MS-2, respectively at UV doses of 1500 mJ/cm². KN95 A yielded the lowest …

Academy Presidents And Institutional Members, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Table Of Contents, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.

Seasonal Testicular Histology And Acystic Lobular Spermatogenesis In The Western Lesser Siren, Siren Intermedia Nettingi (Caudata: Sirenidae), Stanley E. Trauth

Journal of the Arkansas Academy of Science

I investigated the seasonal testicular histology and acystic lobular spermatogenesis in the Western Lesser Siren, Siren intermedia nettingi, from periodic sampling of this salamander over a span of 21 yr (1994-2015) in northeastern Arkansas. My results include the following general findings: 1) the largest testicular lobules occurred primarily in January-February during spermiogenesis and spermatozoa maturation; 2) lobular regression and spermatogenic cell recrudescence were underway by late March; 3) proliferation of secondary spermatogonia in lobules was prominent in May; 4) transformation of secondary spermatogonia into primary spermatocytes occurred by mid-July, and these cells became larger in diameter through increased nuclear …

Dominant Frequency Component Tracking Of Noisy Time-Varying Signals Using The Linear Predictive Coding Pole Processing Method, Jin Xu, Mark Davis, Ruairí De Fréin

Articles

The linear predictive coding pole processing (LPCPP) method proposed in our previous work overcomes the shortcomings of the LPC method, especially its sensitivity to noise and the filter order. The LPCPP method is a parameterised method that involves processing the LPC poles to produce a series of reduced-order filter transfer functions to estimate the dominant frequency components of a signal. This paper analyses the ability of the LPCPP method to track the frequency changes of noisy, time-varying signals in real-time. Linear chirped frequency modulation signals are used in a series of experiments to simulate signals with different rates of frequency …

Formation Of Gold Nanoparticle Self-Assembling Films In Various Polymer Matrices For Sers Substrates, Ksenia A. Maleeva, Ilia E. Kaliya, Anton P. Tkach, Anton A. Babaev, Michail Baranov, Kevin Berwick, Tatiana S. Perova, Alexander V. Baranov, Kirill V. Bogdanov

Articles

Surface-enhanced Raman spectroscopy (SERS) is regarded as a versatile tool for studying the composition and structure of matter. This work has studied the preparation of a SERS substrate based on a self-assembling plasmonic nanoparticle film (SPF) in a polymer matrix. Several synthesis parameters for the SPF are investigated, including the size of the particles making up the film and the concentration and type of the self-assembling agent. The result of testing systems with different characteristics is discussed using a model substance (pseudo isocyaniniodide). These models can be useful in the study of biology and chemistry. Research results contain the optimal …

Mos2 Based Memristive Synapses For Neuromorphic Computing, Adithi Pandrahal Krishnaprasad Sharada

Electronic Theses and Dissertations, 2020-2023

Brain inspired computing enabled by memristors have gained prominence over the years due to its nano-scale footprint, reduced complexity for implementing synapses and neurons. Several demonstrations show two-dimensional (2D) materials as a promising platform for realization of robust and energy-efficient memristive synapses. Ideally, a synapse should exhibit low cycle-to-cycle (C-C) and device-to-device (D-D) variability along with high maximum /minimum conductance (Gmax/Gmin) ratio, linearity and symmetry in weight update for obtaining high learning accuracy in neural networks (NNs). However, the demonstration of neuromorphic circuits using conventional materials systems has been limited by high C-C and D-D variability and non-linearity in the …