Engineering Commons^™

Correlation Of And Development Of Procedure To Use A Resonant Plate With Mechanical Excitation For Shock Testing Small-To-Medium Size Spacecraft And Provide Aerospace Shock Analysis And Testing Guidelines, Monty Kennedy

Dissertations, Master's Theses and Master's Reports

In the aerospace industry it is known that performing shock analysis and testing on spacecraft is difficult to do mostly because shock loads create a very short duration shock wave transient that can have high acceleration peak levels (1,000-5,000 g) and wide frequency content (100-10,000 Hz). FE (finite-element) shock analysis is difficult because implicit linear FE software commonly used for most vibration analysis in aerospace does not account for shock wave propagation, reflection, and attenuation that occurs based upon the distance from the shock source at the base of the spacecraft and the attenuations that occurs through mechanical joints. Spacecraft …

Analysis Of Hemp Fiber Reinforced Polylactide Composite Under High Strain-Rate, Benjamin Rhoads

Honors Theses

The introduction of hemp fibers into a polylactide (PLA) matrix creates a hemp fiber-reinforced composite with 10% hemp fibers and 90% PLA. Natural fibers are becoming a popular alternative to synthetic fibers since they are environmentally friendly, and hemp-fibers are becoming used more often as the demand for natural fibers increased. A Split-Hopkinson Pressure Bar was used to test this composite against a control group using elastic wave propagation theory. Strain gauges were mounted on the incident and transmission bars of the SHPB to measure the propagation of the wave that caused the strain in the sample, which were used …

Factors Affecting United States Geological Survey Irrigation Freshwater Withdrawal Estimates In Utah, J. Levi Manley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Utah is, on average, one of the driest states in the United States, second only to Nevada, and drier conditions are projected. Irrigation is the largest water user in the state, representing about 80% of the total freshwater withdrawn each year. Withdrawals are obtained from sources like reservoirs or streams, or underground water from wells and springs, and supplied for use. The United States Geological Survey, a reputable federal science agency, has provided irrigation freshwater withdrawal estimates every five years since 1950. Understanding what factors affect irrigation withdrawals can better inform water resource planning to reduce withdrawals and conserve surface …

Monte Carlo Perturbation Analysis Of Dimension And Density Variations Of The Annular Core Research Reactor Model Fuel, Karissa Currie

Nuclear Engineering ETDs

This thesis assesses sources of uncertainty in the neutron energy spectrum of the Annular Core Research Reactor (ACRR) Monte Carlo N-Particle Transport Code (MCNP) model. Uncertainty evaluations have been performed on the ACRR core but were computationally intensive and could not isolate the uncertainties associated with discrete sources. Monte Carlo Perturbation Theory (MCPT) is used in MCNP to calculate 640-group neutron energy fluences and their associated uncertainties [1]. To understand the uncertainties associated with only the UO₂-BeO fuel, perturbations in densities and dimensions were evaluated. A 640 by 640 covariance and correlation matrices were produced and compared to …

Forecasting Geotechnical Parameters From Electrical Resistivity And Seismic Wave Velocities Using Artificial Neural Network Models, Fatema Tuz Johora

Electronic Theses and Dissertations

Geotechnical measurements of soil parameters used in the design of infrastructure provide information at a specific point of the ground. The use of limited point data may result in greater uncertainty and less reliability in design. Geophysical methods are non-invasive, less time-consuming, and provide continuous spatial information about the soil. However, geophysical information is not in terms of engineering parameters. Correlations between geotechnical parameters and geophysical parameters are needed to facilitate the use of geophysical information in geotechnical designs. The current research is focused on two geophysical methods; electrical resistivity (ER) and seismic wave velocity (S-wave and P-wave). Artificial neural …

Determining The Correlation Between Plantar Pressure And Joint Kinematics While Running, Fadumo Khalid Mohamud

Master's Theses (2009 -)

Running provides many health benefits, but there is a risk for lower extremity injuries. Previous studies have performed simultaneous assessments of plantar pressure and joint kinematics; however, they have not investigated correlations between these parameters. The goal of this study was to assess correlations between joint kinematics and plantar pressure metrics during the stance phase.Fifteen female and eleven male recreational runners ran ten trials in this study. The joint kinematics were measured using the Vicon MX system and plantar pressure metrics were measured with the Quasar pressure treadmill. Spearman rho correlation tests were performed to determine correlations between joint …

Keyless Anti-Jamming Communication Via Randomized Dsss, Ahmad Alagil

USF Tampa Graduate Theses and Dissertations

Nowadays, wireless networking is ubiquitous. In wireless communication systems, multiple nodes exchange data during the transmission time. Due to the natural use of the communication channel, it is crucial to protect the physical layer to make wireless channels between nodes more reliable. Jamming attacks consider one of the most significant threats on wireless communication. Spread spectrum techniques have been widely used to mitigate the effects of the jammer. Traditional anti-jamming approaches like Frequency Hopping Spread Spectrum (FHSS) and Direct Sequence Spread Spectrum (DSSS) require a sender and a receiver to share a secret key prior to their communication. If this …

The Influence Of Spatial Variance On Rock Strength And Mechanism Of Failure, Danqing Gao

Graduate Theses, Dissertations, and Problem Reports

The heterogeneity in the rock formation affects both rock behavior and the strength. The effect of heterogeneity is observed both at the laboratory scale and at the rockmass level. The mechanical properties of intact rock vary considerably at laboratory scale and often an average value is used for design purposes. Similarly, the values are arbitrarily scaled when used at rockmass level. In underground coal mines, the effect of variability of properties is often observed with the erratic roof failure events that occur throughout the mine. The approach often was to use the deterministic values from limited site data to estimate …

Removing Vehicle Speed From Apparent Wind Velocity, Austin M. Weiss

Theses and Dissertations--Biosystems and Agricultural Engineering

Variable-rate technologies for sprayer applications stand to increase efficacy by ensuring the right amount of chemical is applied at the right location. However, external environmental factors such as droplet drift caused by variable ambient condition, are not yet integrated into modern sprayer systems. Real-time wind velocity measurements can be used to control droplet spectra for reducing spray drift by actuating a variable-orifice nozzle. This work aimed to develop data processing methods needed to filter noise and remove vehicle speed from wind velocity measurements collected with an ultrasonic anemometer aboard a moving platform. Using a global navigation satellite system (GNSS), vehicle …

An Analysis Of Using Error Metrics To Determine The Accuracy Of Modeled Historical Streamflow On A Global Scale, Elise Katherine Jackson

Theses and Dissertations

Streamflow data is used throughout the world in applications such as flooding, agriculture, and urban planning. Understanding daily and seasonal patterns in streamflow is important for decision makers, so that they can accurately predict and react to seasonal changes in streamflow for the region. This understanding of daily and seasonal patterns has historically been achieved through interpretation of observed historical data at stream reaches throughout the individual regions. Developing countries have limited and sporadic observed stream and rain gage data, making it difficult for stakeholders to manage their water resources to their fullest potential. In areas where observed historical data …

Leveraging 3d Models For Sar-Based Navigation In Gps-Denied Environments, Zachary A. Reid

Browse all Theses and Dissertations

This thesis considers the use of synthetic aperture radar (SAR) to provide absolute platform position information in scenarios where GPS signals may be degraded, jammed, or spoofed. Two algorithms are presented, and both leverage known 3D ground structure in an area of interest, e.g. provided by LIDAR data, to provide georeferenced position information to airborne SAR platforms. The first approach is based on the wide-aperture layover properties of elevated reflectors, while the second approach is based on correlating backprojected imagery with digital elevation imagery. Both of these approaches constitute the system we have designated: SARNAV. Building on 3D backprojection, localization …

Real-Time Beamforming Algorithms For The Focal L-Band Array On The Green Bank Telescope, Mark William Ruzindana

Theses and Dissertations

A phased array feed (PAF) provides a contiguous, electronically synthesized wide field of view for large-dish astronomical observatories. Significant progress has been made in recent years in improving the sensitivity of PAF receivers though optimizing the design of the antenna array, cryogenic cooling of the front end, and implementation of real-time correlation and beamforming in digital signal processing. FLAG is a 19 dual-polarized element phased array with cryogenic LNAs, direct digitization of RF signals at the front end, digital signal transport over fiber, and a real time signal processing back end with up to 150 MHz bandwidth. The digital back …

Quantitative Estimation Of Causality And Predictive Modeling For Precipitation Observation Sites And River Gage Sensors, Tri Vu Nguyen

LSU Master's Theses

This project seeks to investigate two questions: correlations from precipitation measurement sensors to river gage sensors, and predictive modeling of peak river gage heights during precipitation events. First, if correlations can be quantified, then a predictive model can be explored to predict peak water levels at river gage sensors, in response to precipitation inputs. Answering both research questions can provide early flood detection benefits and provide quantitative time assessments for flood risks. An extensive data-driven study was conducted across a geographical area of the U.S, spanning the time period 2008-2016 to identify river gage sensors that are closely correlated to …

A Hybrid Approach To Aerial Video Image Registration, Karol T. Salva

Browse all Theses and Dissertations

Many video processing applications, such as motion detection and tracking, rely on accurate and robust alignment between consecutive video frames. Traditional approaches to video image registration, such as pyramidal Kanade-Lucas-Tomasi (KLT) feature detection and tracking are fast and subpixel accurate, but are not robust to large inter-frame displacements due to rotation, scale, or translation. This thesis presents an alternative hybrid approach using normalized gradient correlation (NGC) in the frequency domain and normalized cross-correlation (NCC) in the spatial domain that is fast, accurate, and robust to large displacements. A scale space search is incorporated into NGC to enable more consistent recovery …

The Use Of Cod, Toc, Fluorescence, And Absorbance Spectroscopy To Estimate Biochemical Oxygen Demand In Wastewater, Evelyn Aramaine Christian

UNLV Theses, Dissertations, Professional Papers, and Capstones

All wastewater treatment facilities must obtain a National Pollution Discharge Elimination System (NPDES) permit, which regulates the quality of water that is discharged. Common to all NPDES permits is a limit on organic matter, as determined by the five-day biochemical oxygen demand (BOD5) test. More rapid methods, such as chemical oxygen demand (COD), total organic carbon (TOC), fluorescence, and absorbance spectroscopy are also capable of quantifying organic matter. Previous studies indicate it is possible to develop correlations between these parameters. This study explored the correlations using influent, primary clarifier effluent, and finished effluent samples from an operational wastewater treatment plant …

The Investigation Of Okhissa Dam Using A Real-Time Monitoring System, Corey Alexander Hamil

Electronic Theses and Dissertations

According to the National Inventory of Dams (NID), the United States has approximately 87,000 dams. Many of these dams are more than 50 years old and need to be investigated to ensure their safety to the public. A real time monitoring system can obtain a more reliable evaluation of the dam’s performance as well as serve as an early warning system to inform officials of a dam’s condition. Okhissa Dam was selected for investigation using a real-time monitoring system. Okhissa Dam is located in a region that contains both a phreatic aquifer and a confined aquifer. Prior to this investigation …

Covariance Modeling And Space-Time Coding For Mimo Systems, Farnaz Karimdady Sharifabad

Theses and Dissertations

The full spatial covariance matrix of the multiple input multiple-output (MIMO) channel is an important quantity in channel modeling, communication system signal processing, and performance analysis, and therefore this matrix forms the heart of the research outlined in this dissertation. The work begins with an investigation of a generalized framework for computing the full MIMO spatial covariance based on the power angular spectrum (PAS) of the multipath field and the transmit and receive antenna element radiation patterns. For the case of uniform linear arrays and when the PAS clusters satisfy uniform, truncated Gaussian, or truncated Laplacian distributions, a series expansion …

Reverse Engineering The Structural And Acoustic Behavior Of A Stradivari Violin, Michael A. Pyrkosz

Dissertations, Master's Theses and Master's Reports - Open

There is a tremendous amount of mystery that surrounds the instruments of Antonio Stradivari. There have been many studies done in the past, but no one completely understands exactly how he made his instruments, or why they are still considered the best in the world. This project is designed to develop an engineering model of one of Stradivari's violins that will accurately simulate the structural and acoustic behavior of the instrument. It also hopes to shine some light on what makes the instruments of Stradivari unique when compared to other violins. It will focus on geometry and material properties, utilizing …

Evaluation Of Intelligent Compaction Control In The M-189 Reconstruction Project At Iron River, Michigan, Junhong Li

Dissertations, Master's Theses and Master's Reports - Open

This research evaluated an Intelligent Compaction (IC) unit on the M-189 highway reconstruction project at Iron River, Michigan. The results from the IC unit were compared to several traditional compaction measurement devices including Nuclear Density Gauge (NDG), Geogauge, Light Weight Deflectometer (LWD), Dynamic Cone Penetrometer (DCP), and Modified Clegg Hammer (MCH). The research collected point measurements data on a test section in which 30 test locations on the final Class II sand base layer and the 22A gravel layer. These point measurements were compared with the IC measurements (ICMVs) on a point-to-point basis through a linear regression analysis. Poor correlations …

Modeling Travel Time And Reliability On Urban Arterials For Recurrent Conditions, Prony Bonnaire Fils

USF Tampa Graduate Theses and Dissertations

Abstract

Travel time reliability is defined as the consistency or dependability in travel times during a specified period of time under stated conditions, and it can be used for evaluating the performance of traffic networks based on LOS (Level of Service) of the HCM (Highway Capacity Manual). Travel time reliability is also one of the most understood measures for road users to perceive the current traffic conditions, and help them make smart decisions on route choices, and hence avoid unnecessary delays (Liu & Ma, 2009). Therefore, travel time reliability on urban arterials has become a major concern for daily commuters, …

Structural Identification Through Monitoring, Modeling And Predictive Analysis Under Uncertainty, Hasan Burak Gökçe

Electronic Theses and Dissertations

Bridges are critical components of highway networks, which provide mobility and economical vitality to a nation. Ensuring the safety and regular operation as well as accurate structural assessment of bridges is essential. Structural Identification (St-Id) can be utilized for better assessment of structures by integrating experimental and analytical technologies in support of decision-making. St-Id is defined as creating parametric or nonparametric models to characterize structural behavior based on structural health monitoring (SHM) data. In a recent study by the ASCE St-Id Committee, St-Id framework is given in six steps, including modeling, experimentation and ultimately decision making for estimating the performance …

Stochastic Model For Solar Sensor Array Data, Faris Alfaris

Masters Theses

Statistical approaches are often used in time series analysis, for example, to predict the future trend of a time series. Trend forecasting can be applied in many time related parameters such as: solar radiation, generation of electricity and other variables related to time series to improve the efficiency and to set the design requirements. Since the design of any solar energy system requires knowledge of the availability of solar radiation data at the location of interest. Therefore, this research seeks the application of a statistical model to fit the solar radiation time series and predict the future values. There are …

Cross Sections Used To Elucidate Differences In Wavelet Transforms Of Ground Force Reactions, Wesley John Orme

Boise State University Theses and Dissertations

A study done for the Centers for Disease Control (CDC) found that over 50% of sports related injuries are to the lower extremities [1] with additional studies indicating that females, adolescent through collegiate, have a higher rate of lower extremity sports related injuries than males [2-4]. Conditions surrounding non-contact injuries can be analyzed using ground reaction force (GRF) data from force plates during unanticipated single leg drops, however, the expected gender differences in GRF may not be apparent when viewing data independently in the time or frequency domains.

Graphing the results of a wavelet transform, currently used by scientific, medical, …

Effects Of Environmental Factors On Construction Of Soil-Cement Pavement Layers, John E. Michener

Theses and Dissertations

The specific objectives of this research were to quantify the effects of certain environmental factors on the relative strength loss of soil-cement subjected to compaction delay and to develop a numerical tool that can be easily used by engineers and contractors for determining a maximum compaction delay time for a given project. These objectives were addressed through extensive laboratory work and statistical analyses. The laboratory work involved testing an aggregate base material and a subgrade soil, each treated with two levels of cement. Environmental factors included in the experimentation were wind speed, temperature, and relative humidity, and three levels of …

Semi Autonomous Vehicle Intelligence: Real Time Target Tracking For Vision Guided Autonomous Vehicles, Jonathan D. Anderson

Theses and Dissertations

Unmanned vehicles (UVs) are seeing more widespread use in military, scientific, and civil sectors in recent years. These UVs range from unmanned air and ground vehicles to surface and underwater vehicles. Each of these different UVs has its own inherent strengths and weaknesses, from payload to freedom of movement. Research in this field is growing primarily because of the National Defense Act of 2001 mandating that one-third of all military vehicles be unmanned by 2015. Research using small UVs, in particular, is a growing because small UVs can go places that may be too dangerous for humans. Because of the …

Safety Analyses At Signalized Intersections Considering Spatial, Temporal And Site Correlation, Xuesong Wang

Electronic Theses and Dissertations

Statistics show that signalized intersections are among the most dangerous locations of a roadway network. Different approaches including crash frequency and severity models have been used to establish the relationship between crash occurrence and intersection characteristics. In order to model crash occurrence at signalized intersections more efficiently and eventually to better identify the significant factors contributing to crashes, this dissertation investigated the temporal, spatial, and site correlations for total, rear-end, right-angle and left-turn crashes. Using the basic regression model for correlated crash data leads to invalid statistical inference, due to incorrect test statistics and standard errors based on the misspecified …

Detection, Identification And Classification Of Suck, Swallow And Breathing Activity In Premature Infants During Bottle-Feeding, Fedra Adnani

Theses and Dissertations

Prematurity, especially if extreme, is one of the leading causes of problems and/or death after delivery. Among all the problems encountered by premature infants, feeding difficulties are very common. Many premature infants are fed intravenously at first, and they progress to milk feedings provided by a tube passed into the stomach. At around 34 weeks of gestation, premature infants should be able to breastfeed or take a bottle. At the same time such premature infants are usually faced with difficulty making the transition from tube-feeding to full oral feeding. In this study three physiological measurements of premature infants including sucking, …

Information Analysis Of Dna Sequences, Riyazuddin Mohammed

LSU Master's Theses

The problem of differentiating the informational content of coding (exons) and non-coding (introns) regions of a DNA sequence is one of the central problems of genomics. The introns are estimated to be nearly 95% of the DNA and since they do not seem to participate in the process of transcription of amino-acids, they have been termed “junk DNA.” Although it is believed that the non-coding regions in genomes have no role in cell growth and evolution, demonstration that these regions carry useful information would tend to falsify this belief. In this thesis, we consider entropy as a measure of information …

Pah And Pcb Distribution In Sediment Fractions And Sorptive Phases, Trudy J. Estes

LSU Doctoral Dissertations

Contaminant distribution is integral to environmental evaluations of contaminated sediment on every level. The technical and economic feasibility of treatment or beneficial use is a function of the accessibility or separability of the contaminants within the sediment. The magnitude of release to the environment during dredging and disposal is dependent upon the partitioning behavior of the contaminants. Yet, little attention has been paid to contaminant distribution in the fine sediment fractions. Further, conventional distribution coefficients provide little information regarding the relative contaminant loading of each of the sorptive phases. Bioavailability of contaminants in oil and grease, soot and organic carbon, …

Object Tracking Using Log-Polar Transformation, Saikiran Sri Thunuguntla

LSU Master's Theses

In this thesis, we use log-polar transform to solve object tracking. Object tracking in video sequences is a fundamental problem in computer vision. Even though object tracking is being studied extensively, still some challenges need to be addressed, such as appearance variations, large scale and rotation variations, and occlusion. We implemented a novel tracking algorithm which works robustly in the presence of large scale changes, rotation, occlusion, illumination changes, perspective transformations and some appearance changes. Log-polar transformation is used to achieve robustness to scale and rotation. Our object tracking approach is based on template matching technique. Template matching is based …