Engineering Commons^™

Prediction Of Process-Induced Defects By Ply-Drops In The Design Optimization Of A Complex Composite Laminate, Sitanshu Pandya

Mechanical and Aerospace Engineering Theses - Archive

The objective of this work is to characterize manufacturing process-induced warping defects due to ply drops in composite laminates to guide composite laminate design. Composite laminate optimization seeks weight efficient models, but the process can also generate complex ply geometry, which compounds the challenges of the already rigorous composite laminate manufacturing process. Increased design complexity enhances the likelihood of manufacturing process-induced defects like warping; therefore, it is important to predict such defects in the design phase to make the product more efficient yet producible and thereby avoid such defects. This work study is manufacturing process induced warpage in complex composite …

Investigation And Proposed Remedy Of Vibration Problem In Industrial Crane System Due To Human Operation, Dustin C. Lorance

Civil Engineering Theses - Archive

A recent investigation of a crane system began when a facilities manager reported a runway beam under-going torsional vibration during operations. The investigation revealed the runway beam’s twisting was caused by resonance vibration due to “inching” of the crane hoist. A Fourier spectrum analysis revealed that one of the harmonic frequencies of this rhythmical motion coincided very close to the natural frequency of the crane system. The runway beam, although met strength requirements, failed to meet serviceability criteria due to the resonance vibration. Resonance vibration issues due to human activity in crane operation (inching, sway, etc.) is often encountered by …

Performance Of Lime- And Cement- Based Treatments Of Sulfate-Rich Soil Via Rc Testing, Azadeh Asghariastaneh

Civil Engineering Theses - Archive

Chemical treatment of expansive sulfate-rich soils, particularly lime- and cement-based methods, had been rather popular due to their relatively low cost and ready availability. However, over the last few decades, extensively documented pavement failures, mainly caused by excessive heaving and/or shrinkage of lime- and cement-treated subgrades with moderate-to-high sulfate content, have led to thorough investigations to assess the actual feasibility and effectiveness of calcium based stabilizers in sulfate-rich soils. Studies have concluded, with solid experimental evidence, that the calcium present in the chemical stabilizers react with the sulfate and alumina of the treated soil to form Ettringite, an expansive mineral …

Two Senior Projects: 2.4 Ghz, 40% Efficiency Radio Frequency Amplifier, Ieee Design Contest, & Design And Implementation Of A Software Costas Loop For Audio Frequencies, Robert J. Tong

Electrical Engineering

How to Read this Document:

This document combines two senior project reports. The first senior project documents designing a class AB RF amplifier. The second, discusses the design and implementation of a software Costas loop for audio frequencies. The first report begins on the next page, while the Costas loop report starts on page 24. The two reports are orthogonal from one another. It is not a prerequisite to read the RF amplifier report before reading the Costas loop report. This document is merely two reports combined into one document. The second report, about the Costas loop, was written as …

Using Approximate Dynamic Programming To Control An Electric Vehicle Charging Station System, Ying Chen

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Dynamic programming (DP) as a mathematical programming approach to optimize a system evolving over time has been applied to solve the multi-stage optimization problems in a lot of areas such as manufacturing systems and environmental engineering. Due to the “curses of dimensionality”, traditional DP method is only able to solve a low dimensional problem or problems under very limiting restrictions, In order to employ DP to solve high-dimensional practical complex systems, approximate dynamic programming (ADP) is proposed. Several versions of ADP has been introduced in the literature and for this study, the author takes advantage of design and analysis of …

Crack Healing In 304l Stainless Steel Using Additive Manufacturing And Friction Stir Processing (Fsp), Cameron Scott Gygi

Theses and Dissertations

Continuing an investigation on using FSP to heal stress corrosion cracks (SCC) in welds on nuclear reactors, this study seeks to use AM in addition to FSP to aid crack repair. Previous studies address that current repair technology on nuclear reactors involves the use of TIG welding which can allow helium atoms to aggregate and form voids at the grain boundaries. This weakens the material and renders the repair ineffective. Another previous study evaluated the effectiveness of FSP alone in repairing SCC which did have defects depending on the parameters used during FSP. This study evaluated the use of AM …

Multi-Objective Two-Stage Stochastic Programming For Adaptive Interdisciplinary Pain Management With Piece-Wise Linear Network Transition Models, Gazi Md Daud Iqbal

Industrial, Manufacturing, and Systems Engineering Dissertations - Archive

Pain is the most common symptom when a patient visits a physician. People experience pain throughout their lifetime at different degrees. If short term pain is not treated properly, then it can become long term pain, which is also known as chronic pain. The Eugene McDermott Center for pain management at UT Southwestern Medical Center conducts a two-stage pain management program for chronic pain. This research uses a two-stage stochastic programming approach to optimize personal adaptive treatment strategies for pain management. The goal is to generate adaptive treatment strategies using statistics based optimization approaches that can be used by physicians …

A Supervised Approach For Training Gaussian Mixture Model Classifiers, Vineet Dilip Gundecha

Electrical Engineering Theses - Archive

A new method for training Gaussian Mixture Model (GMM) classifiers is presented. First, an objective function is defined in terms of the number of clusters, K, per class, the mean vectors, the inverse covariance matrices for each class, and the prior probabilities for each class. For each increment in K, gradients of the objective function improve upon the prior probabilities, mean vectors, and inverse covariance matrices. Improvement in accuracy for different data-sets are shown and results are compared with the EM algorithm.

Multi-Source Uav-Based Object Classification Using Cnn’S And Data Acquisition System For Robotic Skin, Raghavendra Sriram Margasahayam Subrahamanyam

Electrical Engineering Theses - Archive

Autonomous robots are intelligent systems capable of performing tasks in the world by themselves, without explicit human control. Examples range from autonomous helicopters to Roomba, the robot vacuum cleaner to robotic manipulators. The numerous sensors onboard gather data related to the desired actions and this poses several challenges and design constraints in terms of computation and hardware design that can prove to be extremely difficult and expensive to avoid. The objective of this research is to study, develop and implement various Intelligent solutions to help solve several real-world problems with respect to multi agent configurations of unmanned systems. We shall …

Dynamic Rating Of Overhead Transmission Lines Over Complex Terrain Using A Large-Eddy Simulation Paradigm, Tyler Phillips, Ray Deleon, Inanc Senocak

Mechanical and Biomedical Engineering Faculty Publications and Presentations

Dynamic Line Rating (DLR) enables rating of power line conductors using real-time weather conditions. Conductors are typically operated based on a conservative static rating that assumes worst case weather conditions to avoid line sagging to unsafe levels. Static ratings can cause unnecessary congestion on transmission lines. To address this potential issue, a simulation-based dynamic line rating approach is applied to an area with moderately complex terrain. A micro-scale wind solver — accelerated on multiple graphics processing units (GPUs) — is deployed to compute wind speed and direction in the vicinity of powerlines. The wind solver adopts the large-eddy simulation technique …

Enhancements In Mass Transfer For Carbon Capture Solvents Part I: Homogeneous Catalyst, Leland R. Widger, Moushumi Sarma, Jonathan J. Bryant, David S. Mannel, Jesse G. Thompson, Cameron A. Lippert, Kunlei Liu

Center for Applied Energy Research Faculty and Staff Publications

The novel small molecule carbonic anhydrase (CA) mimic [Co^III(Salphen-COO⁻)Cl]HNEt₃ (1), was synthesized as an additive for increasing CO₂ absorption rates in amine-based post-combustion carbon capture processes (CCS), and its efficacy was verified. 1 was designed for use in a kinetically slow but thermally stable blended solvent, containing the primary amines 1-amino-2-propanol (A2P) and 2-amino-2-methyl-1-propanol (AMP). Together, the A2P/AMP solvent and 1 reduce the overall energy penalty associated with CO₂ capture from coal-derived flue gas, relative to the baseline solvent MEA. 1 is also effective at increasing absorption kinetics of kinetically fast solvents, such …

Making Public Health Performance Measures For Transportation Accessible To Practitioners, Ziaur Rahman

Civil Engineering Dissertations - Archive

Pollutants emitted into the atmosphere from static and mobile sources pose a threat to human health. The detrimental impact associated with air pollution varies by the type of pollutant, the magnitude, frequency and duration of exposure, and the associated toxicity. While stationary sources play an important role in air pollution, motor vehicle exhaust emissions represent the single largest source of regional air pollution in urban areas. Moreover, outdoor physical activity requires an increased oxygen level with an increase in exercise intensity. Research has shown that both the ventilation and deposition fractions increase significantly during outdoor activities, which may lead to …

Integrated Modeling Of Storm Drain And Natural Channel Networks For Real-Time Flash Flood Forecasting And Stormwater Planning And Management In Large Urban Areas, Hamideh Habibi

Civil Engineering Dissertations - Archive

Urban flash flooding is a serious problem in large highly populated areas such as the Dallas–Fort Worth metroplex (DFW). Being able to monitor and predict flash flooding at a high spatiotemporal resolution is critical to mitigating its threats and for cost effective emergency management. In this reserach, a high-resolution flash flood forecast system which operates in real time is developed for DFW using a gridded distributed hydrologic model and high-resolution quantitative precipitation estimates from the DFW Demostration Network of the Collaborative Adaptive Sensing of the Atmosphere (CASA) Program high-resolution X band radars and the National Weather Service (NWS) NEXRAD radar. …

Building Intelligence In The Automated Traffic Signal Performance Measures With Advanced Data Analytics, Tingting Huang, Subhadipto Poddar, Chris Aguilar, Anuj Sharma, Edward J. Smaglik, Sirisha Kothuri, Peter Koonce

Civil and Environmental Engineering Faculty Publications and Presentations

Automated traffic signal performance measures (ATSPMs) are an effort to equip traffic signal controllers with high-resolution data-logging capabilities and utilize this data to generate performance measures. These measures allow practitioners to improve operations as well as to maintain and operate their systems in a safe and efficient manner. Although these measures have changed the way that operators manage their systems, several shortcomings of the tool, identified by talking with signal operators, are a lack of data quality control and the extent of resources required to properly use the tool for system-wide management. To address these shortcomings, intelligent traffic signal performance …

Lifetime Reliability-Based Optimization Of Post-Tensioned Box-Girder Bridges, Tatiana García-Segura, Victor Yepes, Dan M. Frangopol, David Y. Yang

Civil and Environmental Engineering Faculty Publications and Presentations

This paper presents a lifetime reliability-based approach for the optimization of post-tensioned concrete box-girder bridges under corrosion attack. The proposed approach is illustrated by determining the optimal life-cycle cost and CO2 emissions of several initial designs of post-tensioned box-girder bridges with different objectives, i.e. the lowest initial costs, the longest corrosion initiation time, or the maximum safety. The study was conducted in two steps. Firstly, the Pareto set presents initial designs considering the cross-section geometry, the concrete strength, the reinforcing steel and the prestressing steel. Secondly, the maintenance optimization was conducted with the proposed method, aimed at minimizing the economic, …

Versatile Optochemical Quantification With Optical Mouse, Altamash Fakki, Salahaldein Ahmed, Jongwon Park, Chang-Soo Kim

Electrical and Computer Engineering Faculty Research & Creative Works

There is an ever increasing need for simple, low-cost instruments for ubiquitous medical and environmental measurements in conjunction with networks and Internet-of-things. This work demonstrates that the optical mouse, one of the most common optoelectronic computer peripherals, can be used for chemical quantification. Particularly, we explore the feasibility of using the preassembled optical platform of mouse for oxygen and pH quantification. The image sensor and the light-emitting diode (LED) serve as photodetector and excitation/illumination light source, respectively, while the preinstalled microoptics (e.g., lens and waveguide) provide a fixed optical arrangement convenient for sample analysis. This novel, cost-effective approach demonstrates the …

The Influence Of The Electrode Dimension On The Detection Sensitivity Of Electric Cell–Substrate Impedance Sensing (Ecis) And Its Mathematical Modeling, Xudong Zhang, William Wang, Anis Nurashikin Nordin, Fang Li, Sunghoon Jang, Ioana Voiculescu

Publications and Research

Detection sensitivity is a crucial criterion in the design and application of ECIS sensors. The influence of sensing electrode dimension on detection sensitivity is investigated in this paper. Eight types of ECIS sensors were fabricated, and their experimental results reveal that smaller-radius working electrodes generate more sensitive impedance shift to cell density change. Also, the smaller radius of working electrodes yield higher impedance values, which improves signal-to-noise ratio. In a range from 1.0 mm to 3.5 mm, the distance between the working and counter electrodes does not affect impedance measurements. However, the distance should be large enough to prevent the …

Stress-Based Topology Optimization Of Steel-Frame Structures Using Members With Standard Cross Sections: Gradient-Based Approach, Navid Changizi, Mehdi Jalalpour

Civil and Environmental Engineering Faculty Publications

This article presents a computationally efficient methodology for stress-based topology optimization of steel frame structures with cross-sectional properties that are mapped from I-beam sections of a design manual. To account for the natural variability of the data, this mapping is achieved via quantile regression to derive continuous relationships between cross-sectional area (the design variable) and other section properties. These relationships are used for deriving the gradient of structural performance, which allows using computationally efficient gradient-based optimization schemes. Three frame structures are designed using the proposed algorithm, the resulting designs are compared with traditional compliance-based topology optimization algorithms, and changes in …

On-Chip Training Of Memristor Crossbar Based Multi-Layer Neural Networks, Raqibul Hasan, Tarek M. Taha, Christopher Yakopcic

Electrical and Computer Engineering Faculty Publications

Memristor crossbar arrays carry out multiply-add operations in parallel in the analog domain, and so can enable neuromorphic systems with high throughput at low energy and area consumption. On-chip training of these systems have the significant advantage of being able to get around device variability and faults. This paper presents on-chip training circuits for multi-layer neural networks implemented using a single crossbar per layer and two memristors per synapse. Using two memristors per synapse provides double the synaptic weight precision when compared to a design that uses only one memristor per synapse. Proposed on-chip training system utilizes the back propagation …

Development Of Empirical And Virtual Tools For The Study Of Bicycle Safety, Brent Kostich

Masters Theses

Bicycles have been used as a form of non-motorized transportation for several hundred years. Recently, their use in the transportation realm has been reinvigorated because of growing population densities and efforts to improve environmental sustainability. However, a large deterrent for public use of the bicycle is concern over its level of safety in the transportation environment. The goal of this thesis is to develop two complementary research tools that advance the study of bicycle safety factors.

First, an instrumented probe bicycle (IPB) is constructed from the ground up. The bicycle is outfitted with an array of sensors that are integrated …

2017 Safety Belt Usage Survey In Kentucky, Kenneth R. Agent, Eric R. Green, Erin Lammers-Staats

Kentucky Transportation Center Research Report

The use of safety belts and child safety seats is a proven means of reducing injuries to motor vehicle occupants involved in traffic crashes. The objective of the survey summarized in this report was to establish a statewide safety belt usage rate in Kentucky for 2017. This rate can be compared to those determined from previous surveys. The 2017 statewide survey documents the continued increase in usage associated with the change in the law to allow primary enforcement and related education and enforcement.

Snow And Ice Removal Route Optimization In Kentucky, Benjamin L. Blandford, Erin Lammers-Staats, Eric R. Green

Kentucky Transportation Center Research Report

Each year the Kentucky Transportation Cabinet (KYTC) spends $40-$80 million removing snow and ice from the state’s roadways. Snow and ice removal are accomplished through a system of snow and ice removal routes that are designed to account for location and the attributes of trucks, facilities, materials, and roadways. To identify strategies that will improve and optimize KYTC’s snow and ice removal operations, Kentucky Transportation Center (KTC) researchers used ArcGIS and its Network Analyst extension to study the performance of the Cabinet’s current routing procedures. Building from this investigation, researchers developed optimized snowplow routings for four counties located in KYTC …

Simulation And Prediction Of The Groundwater Level In The Surrounding Area Of The Nebraska Management System Evaluation Area Site In Central Nebraska., Cesar Augusto Gomez Peña

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

An efficient water budget is necessary to develop sustainable practices in irrigated lands and determine future trends. Despite a lack of detailed knowledge, climate change is found to profoundly influence groundwater resources through changes in groundwater recharge, groundwater elevation, and groundwater flow processes. Prediction of the groundwater level (GWL) under a changing climate is essential to improve agricultural management.

The goal of this research is to predict the GWL from 2056 to 2060 in the surrounding area of the MSEA. In order to achieve the target, the first research task is to develop a groundwater flow model and then simulate …

Deep Learning And Transfer Learning In The Classification Of Eeg Signals, Jacob M. Williams

School of Computing: Dissertations, Theses, and Student Research

Deep learning is seldom used in the classification of electroencephalography (EEG) signals, despite achieving state of the art classification accuracies in other spatial and time series data. Instead, most research has continued to use manual feature extraction followed by a traditional classifier, such as SVMs or logistic regression. This is largely due to the low number of samples per experiment, high-dimensional nature of the data, and the difficulty in finding appropriate deep learning architectures for classification of EEG signals. In this thesis, several deep learning architectures are compared to traditional techniques for the classification of visually evoked EEG signals. We …

Exploring The Telecommunications Properties Of The Human Nervous System: Analytical Modeling And Experimental Validation Of Information Flow Through The Somatosensory System, Natalie Hanisch

School of Computing: Dissertations, Theses, and Student Research

The growing field of Body Area Networks (BANs) is providing solutions to the wireless connectivity of wearable and implantable devices with applications in medicine, entertainment, fitness, and military, amongst others. While electromagnetic wave propagation has been the main BANs' enabling technology, the increasingly pervasive nature of these devices encourages novel solutions with added bio-compatibility and sustainability. In this thesis, a novel communication system is proposed for BANs based on the natural propagation of tactile stimuli through the nervous system. This system is composed of a tactile stimulator coupled to an ElectroEncephaloGraphy (EEG) system, and realizes the propagation of somatosensory signals …

Phase Separation In Ti-6al-4v Alloys With Boron Additions For Biomedical Applications: Scanning Kelvin Probe Force Microscopy Investigation Of Microgalvanic Couples And Corrosion Initiation, P. H. Davis, K. Robles, K. Livingston, S. Johns, V. A. Ravi, E. Graugnard, M. F. Hurley

Materials Science and Engineering Faculty Publications and Presentations

To investigate the effect of boron additions on the corrosion behavior of Ti-6Al-4V for potential use in biomedical implants and devices, cast samples of Ti-6Al-4V were alloyed with 0.01% to 1.09% boron by weight and subjected to hot isostatic pressing. Subsequent analysis via scanning Kelvin probe force microscopy and scanning electron microscopy/energy-dispersive spectroscopy revealed the presence of both alpha (α) and beta (β) phase titanium, enriched in aluminum and vanadium, respectively. At all concentrations, boron additions affected the grain structure and were dispersed throughout both phases, but above the solubility limit, needle-like TiB structures also formed. …

A Study On The Impact Of Instruction Set Architectures On Processor’S Performance, Ayaz Akram

Masters Theses

The recent advances in different instruction set architectures (ISAs) and the way those ISAs are implemented have revived the debate on the role of ISAs in overall performance of a processor. Many people in the computer architecture community believe that with current compiler and microarchitecture advances, the choice of ISA does not remain a decisive matter anymore. On the other hand, some researchers believe that this is not the case and they claim that ISAs can still play a significant role in the overall performance of a computer system. Novel heterogeneous architectures exploiting the diversity of different ISAs have been …

Impacts Of Rail Transit Investments On Demographics And Land Use: 1990-2010, Aubrey Trinidad

All Theses

This paper studies the changes in land use and population characteristics around station areas following the building of rail transit stations in 14 major cities in the United States from 1990 to 2010. It answers the question: how have investments in US rail transit made since the 1990s affected land use and demographics? It also looks at the specific effects of investments on population density, race, and ethnicity, means of transportation, median housing value, median household income, vehicle access share, occupations, and land use represented by the share of multifamily versus single-family housing. Using block group level US census data …

Analysis Of Angles-Only Hybrid Space-Based/Ground-Based Approach For Geosynchronous Orbit Catalog Maintenance, Blythe A. Andrews

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Geosynchronous Equatorial Orbit (GEO) is critical to Earth communications, weather monitoring, and national defense. Orbit estimation of GEO objects is difficult due to physical constraints placed on ground-based tracking devices such as weather, object range, and tracking frequency restrictions. These constraints are commonly mitigated through the use of two-way signaling devices for cooperative GEO satellites. However, determining the position and velocity of uncooperative GEO satellites and/or objects is more challenging. The objective of this dissertation is to quantify the increased orbital accuracy of objects in the GEO catalog when the Air Force Space Command Space Surveillance Network (AFSPC SSN) is …

Transient Heterogeneous Electromagnetic Simulation With Dgtd And Behavioral Macromodel, Huan Huan Zhang, Li (Lijun) Jun Jiang, He Ming Yao, Yu Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

A novel hybrid field-circuit simulation method is proposed for transient heterogeneous electromagnetic simulations. It adopts the discontinuous Galerkin time domain (DGTD) method and behavioral macromodel trained by artificial neural network to analyze the electromagnetic structure and circuit network, respectively. Due to the feature of DGTD method and behavioral macromodel, the proposed method can handle not only electromagnetic structures with complex geometries and materials but also manage circuits with unknown internal details. It provides a new approach that has the trainable accuracy to meet today's IP projection requestions. It is also the first time for DGTD algorithm to work with the …