Engineering Commons^™

Developing General Purpose Apps To Automate Image Analysis Of Wave-Augmented-Varicose-Explosion Atomization And Other Multi-Phase Interfacial Flows, Ethan Newkirk

Senior Honors Theses

Atomization involves disrupting a flow of contiguous liquid into small droplets ranging from one submicron to several hundred microns (micrometers) in diameter through the processes of exerting sufficient forces that disrupt the retaining surface tensions of the liquid. Understanding this phenomenon requires high-speed imaging from physical models or rigorous multiphase computational fluid dynamics models. We produce a MATLAB application that utilizes various methods of image analysis to quickly analyze and store mathematical data from detailed image analyses. We present a user with numerous tools and capabilities that provide results that deviate from 1.8% to 8.9% of the original image sequence …

Model-Based And Model-Free Control Approaches In Subgrids: A Conceptual Review Of Control Strategies In Microgrids, Omobolade H. Abioye

Theses and Dissertations

Increased reliance on the power grid and concerns over climate change issues have resulted in the rapid adoption of renewable energy technologies. Consequently, it is necessary to consider how renewable energy resources are combined and controlled. The microgrid serves as the control center for distributed energy resources. This thesis paper introduces the microgrid elements and framework, its control strategies highlighting frequency and voltage control, and the prospects of artificial intelligence for control, considering two significant approaches. Key components of sub grids like the energy management system (EMS) and energy storage systems (ESSs) are discussed, and lastly, the …

Hand Movement Analysis For Surgical Suturing Skill Assessment, Amir Mehdi Shayan

All Theses

To enhance patient safety, surgical education is increasingly incorporating simulation for formative skills assessment and training. However, many standardized assessment tools rely on human raters for performance assessment, which is resource-intensive and subjective. Simulators that provide automated and objective metrics from sensor data can address this limitation. This thesis presents an instrumented bench suturing simulator, patterned after the Clock Face (CF) radial suturing model from the Fundamentals of Vascular Surgery (FVS), for automated and objective assessment of open suturing skills by particularly focusing on biomechanical analysis of hand movements. For this research, 97 participants (35 attending surgeons and fellows, 32 …

Titanium Dioxide Nanomaterial Ink Production Through Laser Ablation Synthesis In Solution For Printed Electronics Applications, Devyn Duryea, Nicholas Mckibben, Jacob Manzi, Taylor Brennan, Harish Subbaraman, David Estrada, Nirmala Kandadai

Electrical and Computer Engineering Faculty Publications and Presentations

Flexible and printed electronics have become increasingly popular as they make possible the production of flexible, low-cost, multifunction devices that are unachievable through traditional manufacturing methods. The printed films are significantly impacted and thus limited by the existing ink production process. Herein, an alternate technique of generating high-quality titanium dioxide (TiO₂) nanoparticle ink compatible with aerosol jet printing using laser ablation synthesis in solution (LASiS) is showcased. Dynamic light scattering data and transmission electron microscopy confirm the particle size distribution. UV–vis measurements are performed, and the Beer–Lambert relationship is used to determine the concentration of the generated ink. …

Head Impact Measurement Using Piezoelectric Sensors, Huda Abdulla Alnuaimi

Theses

The importance of safety measures cannot be overstated, especially when it comes to protecting the human head. Head injuries can have severe, life-altering consequences, as the head is crucial for controlling the entire body. Unlike machines that store data, the human brain's capacity to retain thoughts and memories can be significantly affected by even a single injury. This thesis introduces a method for predicting the specific area of the head that might be injured during an impact. The prediction is based on the intensity and duration of the impact. The innovation of this thesis lies in the use of piezoelectric …

Spin Disorder Control Of Topological Spin Texture, Hongrui Zhang, Yu-Tsun Shao, Xiang Chen, Binhua Zhang, Tianye Wang, Fanhao Meng, Kun Xu, Peter Meisenheimer, Xianzhe Chen, Xiaoxi Huang, Piush Behera, Sajid Husain, Tiancong Zhu, Hao Pan, Yanli Jia, Nick Settineri, Nathan Giles-Donovan, Zehao He, Andreas Scholl, Alpha N'Diaye, Padraic Shafer, Archana Raja, Changsong Xu, Lane W. Martin, Michael F. Crommie, Jie Yao, Ziqiang Qiu, Arun Majumdar, Laurent Bellaiche, David A. Muller, Robert J. Birgeneau, Ramamoorthy Ramesh

Physics Faculty Publications and Presentations

Stabilization of topological spin textures in layered magnets has the potential to drive the development of advanced low-dimensional spintronics devices. However, achieving reliable and flexible manipulation of the topological spin textures beyond skyrmion in a two-dimensional magnet system remains challenging. Here, we demonstrate the introduction of magnetic iron atoms between the van der Waals gap of a layered magnet, Fe₃GaTe₂, to modify local anisotropic magnetic interactions. Consequently, we present direct observations of the order-disorder skyrmion lattices transition. In addition, non-trivial topological solitons, such as skyrmioniums and skyrmion bags, are realized at room temperature. Our work highlights …

The National Center For Reliable Electric Power Transmission Test Facility, Anna Corbitt, Wesley G. Schwartz, Chris Farnell, Juan Carlos Balda, H. Alan Mantooth

Electrical Engineering and Computer Science Faculty Publications and Presentations

Globally, new technological solutions are being studied and developed by researchers in the field of power and energy systems. Before these solutions can be integrated into society as marketable products, thorough testing and validation of the design must be conducted. The National Center for Reliable Electric Power Transmission (NCREPT) is a unique high-power test facility located at the University of Arkansas, Fayetteville, AR, USA. NCREPT is a 12,000-square-foot laboratory space capable of testing power levels up to 6 MVA and offers testing at both the 480 V and 13.8 kV levels. NCREPT's capabilities expand outside of the scope of simply …

Fin Design Topology Optimization For Direct Liquid Cooling Of Multichip Power Modules, Aniket Ajay Ladd, Eric Roman, Yue Zhao, William P. King, Nenad Miljkovic

Electrical Engineering and Computer Science Faculty Publications and Presentations

This article demonstrates the use of topology optimization (TO) to generate optimal fin designs capable of high heat flux removal without increasing the pumping power. We use pseudo-3-D modeling validated against 3-D simulations for thermal-hydraulic performance, which reduces the computational intensity and allows for a wider range of designs to be considered. The accuracy of the pseudo-3-D modeling is aided by allowing the heat transfer coefficient to vary locally with the flow conditions, in contrast to other studies that often assume constant heat transfer coefficient independent of surface shape. We generated TO designs with density fields representing six different conventional …

Optical Wavelength Measurement Based On Microwave-Photonics And Fiber Dispersion, Yongji Wu

All Dissertations

In modern photonics, combining microwave techniques with optical measurements has introduced a novel research direction. This study introduces a novel Microwave Photonics Wavelength Measurement System (MP-WMS), integrating microwave photonics with fiber chromatic dispersion to achieve direct wavelength measurement. Utilizing cost effective single mode optical fibers as dispersion devices, this system employs chromatic dispersion to convert optical frequency domain measurements into microwave time domain measurements. We established a mathematical model to describe how different wavelengths are detected, enhancing the system's effectiveness. The MP-WMS system offers an affordable solution with high resolution. In the experiment, we used a 35km long SM-28 single-mode …

Photovoltaics And Battery-Based End-To-End Direct Current Sustainable Power Networks- Concept, Design, And Control, Vishwas Powar

All Dissertations

The consequences of climate change have emphasized the need for a power network that is centered around green, low-cost, and renewable sources of energy. Currently, photovoltaics (PV) and wind turbines are the only two technologies that can convert renewable energy from the sun and wind, respectively, into large-scale power for the electricity network. This dissertation aims to provide a novel solution to implement direct current-based architecture for PV generation coupled with lithium-ion battery storage in an efficient and sustainable manner. Such a power network can enable efficiency, reliability, low cost, and sustainability with minimum impact on the environment. The first …

Real-Time Degradation Abatement Framework For Energy Storage System In Automotive Application Using Data-Driven Approaches, Laxman Timilsina

All Dissertations

The increasing popularity of electric vehicles (EVs) is driven by their compatibility with sustainable energy goals. However, the decline in the performance of energy storage systems, such as batteries, due to their degradation puts EVs and hybrid electric vehicles (HEVs) at a disadvantage compared to traditional internal combustion engine (ICE) vehicles. The batteries used in these vehicles have limited life. The degradation of the battery is accelerated by the operating conditions of the vehicle, which further reduces its life and increases the reliability and economic concerns for the vehicle’s operation. The aging mechanism inside a battery cannot be eliminated but …

Trust Model Measurements For The Energy Grid Of Things, N. Sonali Fernando, John M. Acken, Robert Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Information security is essential for the reliable operation of an Energy Grid of Things (EGoT). In addition to basic information security protocols as defined by published standards, there is a need for a monitoring function that measures the trustworthiness of the various actors participating in an EGoT. We describe in this paper the implementation and evaluation of a Distributed Trust Model that was developed specifically for monitoring communication within an EGoT. We then show how the model parameters are set using statistical measures for hypothesis testing.

Effectiveness Of Cnn-Lstm Models Used For Apple Stock Forecasting, Ethan White

Electronic Theses, Projects, and Dissertations

This culminating experience project investigates the effectiveness of convolutional neural networks mixed with long short-term memory (CNN-LSTM) models, and an ensemble method, extreme gradient boosting (XGBoost), in predicting closing stock prices. This quantitative analysis utilizes recent AAPL stock data from the NASDAQ index. The chosen research questions (RQs) are: RQ1. What are the optimal hyperparameters for CNN-LSTM models in stock price forecasting? RQ2. What is the best architecture for CNN-LSTM models in this context? RQ3. How can ensemble techniques like XGBoost effectively enhance the predictions of CNN-LSTM models for stock price forecasting?

The research questions were answered through a thorough …

Improved Test Fixture For Collecting Microcontact Performance And Reliability Data, Turja Nandy, Ronald A. Coutu Jr., Rafee Mahbub

Electrical and Computer Engineering Faculty Research and Publications

Microelectromechanical systems (MEMS) ohmic contact switches are considered to be a promising candidate for wireless communication applications. The longevity of MEMS switches is directly related to the reliability and performance of microcontacts. In this work, an improved microcontact test fixture with high actuation rates (KHz) and highly precise position control (nm) and force (nN) control was developed. Here, we collected microcontact performance data from initial contact tests (ICT) and microcontact reliability data from cold switched tests (CST). To perform these tests with our test fixture, we fabricated MEMS microcontact test structures with relatively high Young’s modulus electroplated Nickel (Ni)-based, fixed–fixed …

Design, Fabrication, And Characterization Of Advanced High-Power Single-Mode 9xxnm Semiconductor Lasers, Xiaolei Zhao

All Dissertations

This thesis presents the comprehensive design, fabrication, and demonstration of advanced high-power, high-efficiency single-mode semiconductor lasers operating at a wavelength of 9xxnm. We begin with the design of the laser epitaxial structure, serving as the cornerstone for achieving high-power high-efficiency lasers. Our methodology integrates a semi-analytical calculation model, which accounts for Longitudinal Spatial Hole Burning (LSHB) and Two-Photon Absorption (TPA) effects, facilitating a thorough exploration of how design parameters influence output power and conversion efficiency. This approach offers an effective and time-efficient epitaxial structure optimization strategy compared to conventional full 3D simulation models.

Subsequently, we demonstrate high-power, high-efficiency ridge waveguide …

Robust And Trustworthy Deep Learning: Attacks, Defenses And Designs, Bingyin Zhao

All Dissertations

Deep neural networks (DNNs) have achieved unprecedented success in many fields. However, robustness and trustworthiness have become emerging concerns since DNNs are vulnerable to various attacks and susceptible to data distributional shifts. Attacks such as data poisoning and out-of-distribution scenarios such as natural corruption significantly undermine the performance and robustness of DNNs in model training and inference and impose uncertainty and insecurity on the deployment in real-world applications. Thus, it is crucial to investigate threats and challenges against deep neural networks, develop corresponding countermeasures, and dig into design tactics to secure their safety and reliability. The works investigated in this …

Characterizing The Molecular And Cellular Changes Of Senescent Cells Induced By Diverse Stressors In 2d And 3d Microenvironments, Apoorva Chauhan

UNLV Theses, Dissertations, Professional Papers, and Capstones

Aging is a risk factor for myriad diseases and is often associated with the accumulation of senescent cells. Cellular senescence, a process of irreversible cell cycle arrest, is associated with various changes in cellular morphology and function. While senescence will occur naturally in a time-dependent manner, it can be prematurely induced by various extrinsic and intrinsic factors. Most senescence studies model cell behavior in two-dimensional (2D) microenvironments; however, these models are not physiologically relevant. In this study, the effects of naturally occurring reactive oxygen species (ROS) hydrogen peroxide (H2O2) and commonly used chemotherapy drugs, doxorubicin and palbociclib, on cellular senescence …

Exploring The Effects Of Dopants On The Opto-Electrical Response Of Ge2Se3-Based Optically Gated Transistor (Ogt), Md Faisal Kabir

Boise State University Theses and Dissertations

In this work, the electrical and optical responses of chalcogenide glass (ChG) Ge₂Se₃-based optically gated transistors (OGTs) were investigated. The device can act as a selector for resistive memory devices and potentially enable the production of functional high-density resistive (and memristive) arrays.

The OGT was developed using a Ge₂Se₃-based material heterostructure and demonstrated to successfully gate a memristor with light. The light intensity provided a built-in compliance current, allowing multi-state programming. By varying the light intensity incident on Ge₂Se₃ material, a family of current-voltage (I-V) curves were measured that …

On-Chip Active Pulse-Clamp Stimulation (Apcs) For Rapid Recovery, Charge-Balanced Neural Stimulation, F. N. U. Tala

Boise State University Theses and Dissertations

Neurostimulations are widely utilized to modulate brains and nervous systems functions for therapeutic purposes. Traditional neurostimulation involves applying a direct current delivered to the excitable tissues to elicit neural response. There is a growing demand for a robust, rapid stimulation system that ensures chronic safety through charge balancing in vivo. This dissertation is a compilation of previously published works, detailing various board-level stimulators, an innovative on-chip stimulation technique, and a distributed modelling method.

Chapter one introduces MEDUSA, a cost-effective, multi-functional neurostimulation system capable of achieving multi-channel, arbitrary stimulation for neuroscience research.

Chapter two delves into a scripted distributed model framework …

Traffic Prediction In 5g Networks Using Machine Learning, Hossein Mehri

Boise State University Theses and Dissertations

The advent of 5G technology promises a paradigm shift in the realm of telecommunications, offering unprecedented speeds and connectivity. However, the efficient management of traffic in 5G networks remains a critical challenge. It is due to the dynamic and heterogeneous nature of network traffic, including bursty patterns, varying user behaviors, and diverse applications, all of which demand highly accurate and adaptable prediction models to optimize network resource allocation and management. This dissertation investigates the intricate domain of traffic prediction within 5G networks, addressing the specific challenges posed by both massive machine type communication (mMTC) networks and 5G cellular networks.

The …

4-Channel Spatially Multiplexed Communication System In Single-Core Optical Fibers, Ce Su

Theses and Dissertations

This dissertation delves into exploring and advancing spatial domain / space division multiplexing (SDM) technologies within single-core optical fibers, a frontier in optical fiber communications poised to meet the burgeoning global demand for data transmission. At the heart of this research is the pursuit to significantly enhance the capacity and efficiency of optical fiber communication systems without necessitating additional fiber infrastructure. This work unveils a new paradigm in optical fiber communications characterized by a pioneering 4-channel SDM system through a meticulous process encompassing theoretical modeling, computational simulations, design innovations, and rigorous experimental validations. Theoretical contributions include the development of refined …

High Performance Silicon Carbide Based Converters For Powertrain Electrification, Nan Lin

Graduate Theses and Dissertations

With the increasing concern towards environment protection, electric vehicles (EVs) and hybrid electric vehicles (HEVs) have become popular in recent years. They not only help reduce carbon emissions, but also come with other benefits such higher efficiency and better user experience. Many countries and vehicle manufactures have made their plans to keep up with this trend in vehicle electrification. Powertrain is an assembly of components in a vehicle that pushes it forward. As for EVs and HEVs, their powertrains are composed of one or more power electronics converters, which are significant to the system. Silicon carbide MOSFETs have shown superior …

Hierarchical Power Converter Physical Design, Tristan Mark Evans

Graduate Theses and Dissertations

The field of power electronics is undergoing rapid advancement that is driven by the need for further electrification in all aspects of power generation and transmission, transportation, and consumer goods. Recent advances in wide bandgap (WBG) semiconductor technologies continue to push their adoption in systems with higher power densities and conversion efficiencies. However, the way in which the components of these systems are designed has not kept pace with the rapidly evolving landscape of their applications and often requires costly, manual design iteration. Therefore, new methods are needed to improve this design process. Packaging of power devices is a critical …

High-Power Dc-Dc Transformer For Medium-Voltage Grids With High-Voltage Sic Technology, Roderick Gomez

Graduate Theses and Dissertations

The objective of this dissertation is to present the theoretical analysis, design process, application and manufacturing of a proposed solid-state transformer intended for medium-voltage applications with minimal high-frequency oscillations. Galvanic isolation on medium-voltage DC-DC converters tend to employ large number of turns in the high voltage side of the transformers leading to non-negligible parasitic stray capacitances which form resonance tanks with the transformer inductances. Therefore, it is critical to estimate these parasitic capacitances to avoid severe high frequency oscillations which can significantly impact the converter performance. The main contribution of this thesis is the extension of a proposed custom-core design …

Design And Implementation Of High-Frequency Dc-Dc Converters For Ev Applications, Rahul Biswash

Graduate Theses and Dissertations

The power electronics industry has been revolutionized by introducing wide bandgap semiconductor devices, such as Silicon Carbide (SiC) and Gallium Nitride (GaN). Due to their high frequency, high temperature, and high voltage operating capabilities, wide bandgap devices boast significant improvements in power density, efficiency, and reliability, as evidenced by their ability to decrease the size of power converters by operating at higher frequencies, temperatures and voltages, use of smaller and less passive components, such as transformers, inductors and capacitors, which makes power converters more compact and light-weight, ideal for space and weight-constrained applications, and compatibility with a wide range of …

Algorithms For Structural Synthesis Of Control Systems For Dynamic Objects Under Conditions Of Unmeasurable Disturbances, Husan Zakirovich Igamberdiev, Uktam Farkhodovich Mamirov, Bunyod Mamurjon Ugli Buronov

Chemical Technology, Control and Management

The paper talks about ways to use inverse dynamic models to structure a control system for moving objects when disturbances are not measured. To solve the main problems that arise when implementing the inverse dynamic model method, methods for synthesizing inverse systems with given dynamic characteristics are used. The solution to this problem is obtained based on the theory that dynamic observers are invariant to unmeasured input influences. We broke down the matrix operator on the right into elementary orthogonal rotation matrices and on the left into permutation matrices to get a stable answer to the equation of the current …

Features Of Magnetoelastic Converters Of Mechanical Quantities Of Transformer Type, Sulton Amirov, Kamila Jurayeva

Chemical Technology, Control and Management

The article discusses the features of a magnetoelastic transformer type transducer. In magnetoelastic transformer-type transducers, mutual inductance is assumed as a variable value, which is a function of the value of the applied mechanical force. Hence, the transformation coefficients of such converters are also variable. There are also choke type converters in which a change in the magnetic permeability of the magnetic circuit leads to a change in the total electrical resistance of the choke. For further research, transformer-type converters were selected, which make it possible to widely implement techniques for improving basic characteristics.

Modernization Of Water Flow Measurement In Open Irrigation Systems Using The Slope-Area Method, R.M. Aliev, Djalilov Anvar

Chemical Technology, Control and Management

This article describes two methods for determining water flow in open irrigation systems: “speed - area” and “slope - area”. The authors considered the problem of its modernization using the existing method for determining water flow “slope - area” in open irrigation systems. The essence of the issue is the remote transfer of parameters necessary for calculating water flow in open irrigation systems and improving the means of their processing. In scientific studies conducted by the authors, the required hydraulic parameters were studied using the “slope - area” and “speed - area” water flow methods. Based on experimentally obtained data, …

Improving Technology For Producing Complex Fertilizer From Low-Grade Phosphorites Of The Central Kyzylkum, A.Zh. Allamuratova, A.U. Erkaev, A.M. Reimov, Saparbay Kazakhbaev, Dilshodbek Kurbiyazov

Chemical Technology, Control and Management

The methods of nitric acid processing of phosphate raw materials are analyzed. A technology has been developed for the nitric acid processing of phosphate raw materials into nitrogen-phosphorus fertilizer with the implementation of the process in a condensed pulp by adding sulfuric acid. A technology for producing complex fertilizers with a wide range of N:P₂O₅:K₂O ratios with improved physico-chemical parameters due to the introduction of various potassium salts into the process is proposed.

Artificial Neural Network Based Grain Moisture Measuring Device, Erkin Eljaev, Shohrux Nurali O‘G‘Li Narzullayev, Elyor Faxriddinovich Khudoyberdiev

Chemical Technology, Control and Management

To date, the intellectualization of solving technical issues in managing, controlling, and measuring technological processes in all branches of industrial production is considered an urgent task. In this regard, a class of intelligent devices and sensors has emerged. Intelligent devices and sensors differ from their analog counterparts in that they have functions such as automatic adjustment of the measurement range, self-calibration, data processing, and decision-making. The article discusses the development of intelligent measuring instruments based on a capacitive transducer for measuring the moisture content of grain and grain products.