Engineering Commons^™

Quasi-Particle Band Structure And Excitonic Effects In One-Dimensional Atomic Chains, Eesha Sanjay Andharia

Graduate Theses and Dissertations

The high exciton binding energy in one dimensional (1D) nano-structures makes them prominent for optoelectronic device applications, making it relevant to theoretically investigate their electronic and optical properties. Many-body effects that are not captured by the conventional density functional theory (DFT) have a huge impact in such selenium and tellurium single helical atomic chains. This work goes one step beyond DFT to include the electron self-energy effects within the GW approximation to obtain a corrected quasi-particle electronic structure. Further, the Bethe-Salpeter equation was solved to obtain the absorption spectrum and to capture excitonic effects. Results were obtained using the Hyberstein-Louie …

Exfoliation, Synthesis, And Characterization Of Nanoscale Te, Takayuki Hironaka

Graduate Theses and Dissertations

Since the experimental discovery of graphene, two dimensional materials have enjoyed more attention and emphasis in academic research than nanowires, but the latter are an important area of study for creating 1D materials, or single atom chains, the next generation materials for advancing electronic devices. Atomically thin layers can be generated from 2D materials with weak bonds in one direction, and by applying this concept to one dimensional weakly bonded materials, we hypothesize that single atom chains with atomic-scale diameters may be produced. Tellurium (Te) and selenium (Se) have lattices consisting of spiral chains oriented along the c-axis, and each …

Gesn Thin Film Epitaxy And Quantum Wells For Optoelectronic Devices, Perry Christian Grant

Graduate Theses and Dissertations

Group IV photonics is an effort to generate viable infrared optoelectronic devices using group IV materials. Si-based optoelectronics have received monumental research since Si is the heart of the electronics industry propelling our data driven world. Silicon however, is an indirect material whose optical characteristics are poor compared to other III-IV semiconductors that make up the optoelectronics industry. There have been major efforts to integrate III-V materials onto Si substrates. Great progress on the integration of these III-V materials has occurred but incompatibility with CMOS processing has presented great difficulty in this process becoming a viable and cost-effective solution. Germanium …

Growth And Behaviors Of Inn/Gan Multiple Quantum Wells By Plasma-Assisted Molecular Beam Epitaxy, Chen Li

Graduate Theses and Dissertations

Fully realizing the potential of InGaN semiconductors requires high quality materials with arbitrary In-content. To this date the growth of In-rich InGaN films is still challenging since it suffers from the low growth temperatures and many detrimental alloying problems. InN/GaN multiple quantum wells (MQWs) and super lattices (SLs) are expected to be promising alternatives to random InGaN alloys since in principle they can achieve the equivalent band gap of InGaN random alloys with arbitrarily high In-content and at the same time bypass many growth difficulties.

This dissertation focuses on studying the growth mechanisms, structural properties and energy structures of InN/GaN …

Fabrication And Characterization Of Electrochemical Glucose Sensors, Mohammed Marie

Graduate Theses and Dissertations

Electrochemical sensors based on the nanostructure of the semiconductor materials are of tremendous interest to be utilized for glucose monitoring. The sensors, based on the nanostructure of the semiconductor materials, are the third generations of the glucose sensors that are fast, sensitive, and cost-effect for glucose monitoring.

Glucose sensors based on pure zinc oxide nanorods (NRs) grown on different substrates, such ITO, FTO, and Si/SiO2/Au, were investigated in this research. Silicon nanowire (NW)- based glucose sensors were also studied. First, an enzyme-based glucose sensor was fabricated out of glass/ITO/ZnO NRs/BSA/GOx/nafion membrane. The sensor was tested amperometrically at different glucose concentrations. …

Pr3+ Doped Bao:Zno:B2o3:Teo2 Glasses For Laser Host Matrix, R Rajaramakrishna, C Wongdeeying, P Yasaka, P Limkitjaroenporn, N Sangwaranatee, J Kaewkhao

Journal of Metals, Materials and Minerals

In this work, glasses of composition (30-x)TeO2-30B2O3-10ZnO-30BaO-xPr2O3 x=0.00 0.05, 0.10, 0.50, 1.00, 1.50 mol% have been prepared through the melt quenching method. In order to characterize and explore their structural properties, we measured the density, refractive index of the glass which shows increasing trend with increase in Pr2O3 concentration also FTIR and XRD spectrum is used to study the structural properties of the developed glasses. XRD shows amorphous structure of the prepared glasses. FTIR shows B-O stretching (BO3)- units and Symmetrical stretching vibration of Te-O in TeO4. The electronic states belonging to the 4f configuration of trivalent Pr3+ were determined …

A Study Of Microcrystalline Cellulose Prepared From Parawood (Hevea Brasiliensis) Sawdust Waste Using Different Acid Types, P Chuayplod, D Aht-Ong

Journal of Metals, Materials and Minerals

Microcrystalline cellulose (MCC) from parawood sawdust (PWS) was successfully prepared by acid hydrolysis method. In this work, parawood sawdust waste was obtained from furniture factory. Initially, PWS was subjected to an alkali pulping and bleaching processes, respectively. After that, the microcrystalline cellulose was prepared from bleached pulp using hydrochloric and sulfuric acid in order to compare the effect of acid type. The parameters for acid hydrolysis process were investigated in terms of reaction time and pulp to acid ratio at constant temperature of 80oC. The properties of obtained MCC such as functional groups, degree of polymerization (DP), crystallinity index (CrI), …

Amplifying The Prediction Of Team Performance Through Swarm Intelligence And Machine Learning, Erick Michael Harris

Master's Theses

Modern companies are increasingly relying on groups of individuals to reach organizational goals and objectives, however many organizations struggle to cultivate optimal teams that can maximize performance. Fortunately, existing research has established that group personality composition (GPC), across five dimensions of personality, is a promising indicator of team effectiveness. Additionally, recent advances in technology have enabled groups of humans to form real-time, closed-loop systems that are modeled after natural swarms, like flocks of birds and colonies of bees. These Artificial Swarm Intelligences (ASI) have been shown to amplify performance in a wide range of tasks, from forecasting financial markets to …

Cloud Based Wireless Sensor Monitoring, Pruthvi Devendrakumar Mistry

Theses and Dissertations

Internet of Things (IoT) brought a revolutionary change in embedded systems. It offloads the physical work of managing an equipment, appliance or device to a smart and network connected application. IoT makes it possible to monitor and control a huge network of devices remotely. The aim of this project is to develop a complete framework for smart data acquisition from a wireless sensor network to cloud servers. The framework includes configurable, low power, and small size embedded module that is attached to a sensor. The device reads data from the sensor and forwards them to the cloud server using the …

Human-Centered Design Of The Enhanced Pilot Learning Interface For The Aviation Community, De Vere Michael Kiss

Theses and Dissertations

he purpose of this research is to introduce a new device to help pilots navigate aircraft manuals. This informational navigational tool is designed to improve learning by reducing the time it takes a pilot candidate to retrieve aircraft system information within an aircraft manual. The device is called the Enhanced Pilot Learning Interface, an Advanced Interactive Media. The research project is based on human-centered design and consists of participatory design, modeling and simulation, human-in-the-loop simulation (HITLS), and expert user experience. Additionally, a traditional research experimentation was conducted to collect supporting statistical data. Preliminary tests of four current professional airline pilots …

An Approach To Improve Single Photon Detectors For Highly Sensitive Applications, Ahmed Chyad Kadhim

Theses and Dissertations

The problem of detecting a single photon is receiving considerable attention with the development of new single photon detectors in biophotonics, stressed free-space optical communication, low probability of intercept (LPI) optical communication, quantum communication, and remote sensing. The theoretical modeling of the waveforms of the single photon detector output produced in particular systems will expedite the search for and analysis of detected signals. Since SNSPDs require cooling to very low temperature, 4K, and PMTs work on the visible wavelength, current photon detection focus on research developing SPADs and using InGaAs/InP materials. However, SPADs can work over the infrared range of …

Phonon Polariton Enhanced Infrared Waveguides, Yuchen Yang

Theses and Dissertations

The need for robust, reliable and sensitive terahertz (THz) sources and detectors has motivated the research into waveguiding structures. The increasing adoption of micro- and nanofabricated optical components addresses the critical challenge of guiding light with subwavelength confinement. Surface plasmon polariton (SPP) waveguides are among the most promising candidates for manipulating light on subwavelength scales and harbor many potential applications at visible and nearinfrared (NIR) wavelengths. However, the metal in the waveguide yields very weak or nonexistent response in the mid and long wave infrared range, since metal in this region is very lossy and has large magnitude real and …

Compensation Of Vertical Position Error Using A Force–Deflection Model In Friction Stir Spot Welding, Jinyoung Yoon, Cheolhee Kim, Sehoon Rhee

Mechanical and Materials Engineering Faculty Publications and Presentations

Despite increasing need for friction stir spot welding (FSSW) for high-temperature softening materials, system deflection due to relatively high plunging force remains an obstacle. System deflection results in the vertical position error of a welding tool and insufficient plunge depth. In this study, we used adaptive control to maintain plunge depth, the plunging force was coaxially measured, and the position error was estimated using a force–deflection model. A linear relationship was confirmed between the force and deflection; this relationship is dependent on the stiffness of the welding system while independent of process parameters and base materials. The proposed model was …

Autonomous Collision Avoidance In Small Scale Vehicles, Justin T. Sharpe

Honors Theses

The undergraduate research performed in this study focused on autonomous collision avoidance in small scale vehicles. The goal of this study was to find equipment to build a fully autonomous small scale vehicle for use in different applications. Radio frequency communication, ultrasonic sensors, and single board computers were used to create an autonomous vehicle for multiple applications. Different communication protocols and sensors were investigated, and an explanation was specified concerning the hardware choice. The main communication protocol tested was Long Range Wide Area Network, and the main electronics tested and used were ultrasonic sensors, First Person View cameras, and the …

Capillary-Tube Package Devices For The Quantitative Performance Evaluation Of Nuclear Magnetic Resonance Spectrometers And Pulse Sequences, Lingyu Chi, Ming Huang, Annalise R. Pfaff, Jie Huang, Rex E. Gerald Ii, Klaus Woelk

Electrical and Computer Engineering Faculty Research & Creative Works

With the increased sensitivity of modern nuclear magnetic resonance (NMR) spectrometers, the minimum amount needed for chemical-shift referencing of NMR spectra has decreased to a point where a few microliters can be sufficient to observe a reference signal. The reduction in the amount of required reference material is the basis for the NMR Capillary-tube Package (CapPack) platform that utilizes capillary tubes with inner diameters smaller than 150 µm as NMR-tube inserts for external reference standards. It is shown how commercially available electrophoresis capillary tubes with outer diameters of 360 µm are filled with reference liquids or solutions and then permanently …

Scale-Out Algorithm For Apache Storm In Saas Environment, Ravi Kiran Puttaswamy

School of Computing: Dissertations, Theses, and Student Research

The main appeal of the Cloud is in its cost effective and flexible access to computing power. Apache Storm is a data processing framework used to process streaming data. In our work we explore the possibility of offering Apache Storm as a software service. Further, we take advantage of the cgroups feature in Storm to divide the computing power of worker machine into smaller units to be offered to users. We predict that the compute bounds placed on the cgroups could be used to approximate the state of the workflow. We discuss the limitations of the current schedulers in facilitating …

Reducing The Tail Latency Of A Distributed Nosql Database, Jun Wu

School of Computing: Dissertations, Theses, and Student Research

The request latency is an important performance metric of a distributed database, such as the popular Apache Cassandra, because of its direct impact on the user experience. Specifically, the latency of a read or write request is defined as the total time interval from the instant when a user makes the request to the instant when the user receives the request, and it involves not only the actual read or write time at a specific database node, but also various types of latency introduced by the distributed mechanism of the database. Most of the current work focuses only on reducing …

Concentrically Loaded Circular Rc Columns Partially Confined With Frp, Sahar Y. Ghanem, Issam E. Harik

Civil Engineering Faculty Publications

Wrapping reinforced concrete (RC) columns with fiber reinforced polymer (FRP) composites is effective in increasing their capacity. The current state of the art concentrates primarily on fully wrapped columns and few studies dealt with partially wrapped ones. The objective herein is to evaluate the effectiveness of partial wraps (or strips) and to develop a confined concrete compressive stress–strain (f_c − ε_c) model that accounts for partial wrapping. Three-dimensional finite element (FE) models are generated to evaluate the influence of different parameters on the behavior of concentrically loaded RC circular columns that are partially and fully wrapped …

Investigation Of Electrolytic Flocculation For Microalga Scenedesmus Sp Using Aluminum And Graphite Electrodes, Shihong Liu, Husam A. Abu Hajar, Guy Riefler, Ben J. Stuart

Civil & Environmental Engineering Faculty Publications

Electrolytic flocculation using non-sacrificial electrodes with flocculants added was studied on harvesting Scenedesmus sp. In order to optimize the operating conditions of the electrolytic flocculation process and to quantify the amount of flocculants added, aluminum electrodes were first used in the process. It was found that under optimal conditions, the microalgae removal efficiency using aluminum electrodes could reach 98.5%, while 34.2 mg L^-1 of aluminum ions were released during the process. Different metal electrodes were also studied, but high microalgae removal efficiency was witnessed only using aluminum electrodes, indicating the influence of the aluminum ion in flocculation. When non-sacrificial …

Process-Property-Microstructure Relationships In Laser-Powder Bed Fusion Of 420 Stainless Steel., Subrata Deb Nath

Electronic Theses and Dissertations

Laser-powder bed fusion (L-PBF) is an additive manufacturing technique for fabricating metal components with complex design and customized features. However, only a limited number of materials have been widely studied using L-PBF. AISI 420 stainless steel, an alloy with a useful combination of high strength, hardness, and corrosion resistance, is an example of one such material where few L-PBF investigations have emerged to date. In this dissertation, L-PBF experiments were conducted using 420 stainless steel powders to understand the effects of chemical composition, particle size distribution and processing parameters on ensuing physical, mechanical and corrosion properties and microstructure in comparison …

Characterization Of Microreactor And Analysis Of Carbonyl Compounds In Exhaled Breath., Qi Li

Electronic Theses and Dissertations

Analysis of trace volatile organic compounds at parts per billion (ppbv) to parts per trillion (pptv) level has become an important research frontier because of the applicability for environmental monitoring and noninvasive diagnosis of diseases. The methods of preconcentration for detection of trace aldehydes and ketones both in ambient air and human exhaled breath have increased considerably over the last decade. However, the majority of these methods are not efficient. In this dissertation, we have improved an innovative microreactor that is suitable for quantitative analysis of volatile carbonyl compounds (VOCs) in ambient air as well as in human exhaled breath. …

Exploration Of Radiation Damage Mechanism In Mems Devices., Pranoy Deb Shuvra

Electronic Theses and Dissertations

We explored UV, X-ray and proton radiation damage mechanisms in MEMS resonators. T-shaped MEMS resonators of different dimensions were used to investigate the effect of radiation. Radiation damage is observed in the form of resistance and resonance frequency shift of the device. The resistance change indicates a change in free carrier concentration and mobility, while the resonance frequency change indicates a change in mass and/or elastic constant. For 255nm UV radiation, we observed a persistent photoconductivity that lasts for about 60 hours after radiation is turned off. The resonance frequency also decreases 40-90 ppm during irradiation and slowly recovers at …

Landmine Detection Using Semi-Supervised Learning., Graham Reid

Electronic Theses and Dissertations

Landmine detection is imperative for the preservation of both military and civilian lives. While landmines are easy to place, they are relatively difficult to remove. The classic method of detecting landmines was by using metal-detectors. However, many present-day landmines are composed of little to no metal, necessitating the use of additional technologies. One of the most successful and widely employed technologies is Ground Penetrating Radar (GPR). In order to maximize efficiency of GPR-based landmine detection and minimize wasted effort caused by false alarms, intelligent detection methods such as machine learning are used. Many sophisticated algorithms are developed and employed to …

An Assessment Tool To Analyze Code Written In App Inventor, Rohit Gopalan

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Assessment plays a significant role in today’s educational field. When creating an assessment tool, we should keep in mind that the tool measures learning, supports learning and encourages learning. Many assessment tools are available in the educational market such as Dr. Scratch, FCS1 Assessment Instrument, and Beyond the rubric. These tools help teachers to evaluate students’ performance in programming activities, but they do not completely measure the creativity shown by students in programming. For example, Dr. Scratch measures abstraction, problem decomposition, and parallelism. FCS1 Assessment Instrument measures a set of foundational computer science concepts like variables, loops, and arrays. It …

Using An Engineering Design Process To Bring The Local Community Into The Technology And Engineering Education Classroom, James M. Baker

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

This plan B project documents the practice of using an authentic project to teach an engineering design process to high school pre-engineering students and documenting the project preparing a manuscript for journal publication.

The manuscript prepared for publication explores the details of working with local business owners and teachers from different departments and curricular foci to design, fabricate, and install an illuminated sign for a local business. This sign project was presented by an alum of the school to provide an authentic project for multiple courses to collaboratively create a solution for a local community business. Twenty-five students in two …

Inter-Laminar Fracture Of 3d-Printed Plastics - Development Of Methods, Christopher Stolinski

All Graduate Plan B and other Reports, Spring 1920 to Spring 2023

Due to the increased use of 3D printed acrylonitrile butadiene styrene (ABS) plastic parts, a way to quantify the failure energy (energy needed to initiate cracking) is needed. Impact tests at high rates of loading are performed to determine failure energy. Throughout testing, specimens are monitored with high speed cameras to perform camera-based deformation measurements. Data acquisition and processing methods to calculate failure energy using crack opening displacement, and loading rates are developed to enable further use by Dr. Ryan Berke’s lab at Utah State University.

Object Detection, Classification, And Tracking For Autonomous Vehicle, Milan Aryal

Masters Theses

The detection and tracking of objects around an autonomous vehicle is essential to operate safely. This paper presents an algorithm to detect, classify, and track objects. All objects are classified as moving or stationary as well as by type (e.g. vehicle, pedestrian, or other). The proposed approach uses state of the art deep-learning network YOLO (You Only Look Once) combined with data from a laser scanner to detect and classify the objects and estimate the position of objects around the car. The Oriented FAST and Rotated BRIEF (ORB) feature descriptor is used to match the same object from one image …

A Systematic Approach To High Blood Pressure Risk Analysis And Healthcare Cost Reduction In Young Adults [Metodología Sistemática Para El Análisis De Riesgo Y Reducción De Costos De Servicios Médicos De Hipertensión En Adultos Jóvenes], Francisco Rafael Torres Diaz

Theses and Dissertations

The purpose of this research is to utilize publicly available data to estimate the current rate of occurrence of undiagnosed High Blood Pressure (HBP) in young adults (18 to 24 years old) and the out-of-pocket healthcare expenses associated with complications of HBP, to provide feasible alternatives to mitigate the effects on a region's economy. This has been done by building a Risk Factor Simulation Model that utilizes known HBP risk factors’ correlation to HBP, insurance coverage data, and rate of diagnosis to formulate the average Risk Factor Value for a region, which through an Annual Expected Cost Function estimates the …

Improving Ductility Of Slender Reinforced Concrete Shear Walls With Frp Sheets And Splay Anchors, Luke M. Ostrom

Architectural Engineering

The Sylmar earthquake of 1971 caused significant damage to slender, non-ductile reinforced concrete (RC) shear wall buildings in California. A later survey by the Concrete Coalition in 2011, under the guidance of EERI members, indicated that there are over 3000 vulnerable concrete buildings in California [8]. This led to City of Los Angeles (LA) Ordinance 193893 enacted in 2015, which requires mandatory upgrades to these concrete buildings by 2035. Current practice to meet the requirements of this ordinance, with respect to RC wall buildings, involves adding new shear walls to the building plan or increasing the cross-sectional area of existing …

Automation Of Post-Earthquake Civil Infrastructure Reconnaissance, Jack Bergquist

Architectural Engineering

Traditionally post-earthquake structural engineering reconnaissance consists of a team of experts who are deployed to the field to record and capture earthquake damage data, which is later uploaded into online repositories. Despite many advances to these data archives in recent years, the entries in online repositories often have limited metadata which make it difficult and time consuming to extract specific damage evidence that can be used for meaningful analysis. This report outlines the author’s contributions to overcoming these challenges via the development of a neural network that automatically filters and classifies post-earthquake civil infrastructure damage data after a seismic event. …