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Performance Evaluation Of 3rd Normal Form Decompositions, Ben Mathew May 2019

Performance Evaluation Of 3rd Normal Form Decompositions, Ben Mathew

Theses and Dissertations

When a relational database is chosen, normalization theory is a set of guidelines that may lead to efficient database designs. Thus, normalization of tables in a database is a common process used for the analysis of relational databases. Sufficient normalization of databases aims to decompose existing relational tables in order to minimize database redundancy while preserving dependencies between attributes. It also facilitates correct insertion, deletion, and modification of data in the database. Given an un-normalized relational database, a redesign with no data redundancy and which is guaranteed to preserve dependencies is not always achievable. Previous studies have shown that it …

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Establishing A People Qualification Framework At Embraer Executive Aircraft, Inc., Yassine Rayad May 2019

Establishing A People Qualification Framework At Embraer Executive Aircraft, Inc., Yassine Rayad

Theses and Dissertations

Technical training in the aviation industry is a multi-faceted and complex topic. Research efforts in aviation maintenance training are extensive, however, we observe a paucity of studies directly focused on aircraft manufacturing environments. Nevertheless, the recent growth of the training industry and the advent of more disruptive technologies such as virtual and augmented reality solutions are making training program design efforts more and more relevant. The research and design contributions presented in this thesis focus on the establishment of a people qualification framework at a local aircraft final assembly and testing plant in Melbourne, FL. The design thinking cycle was …

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Hybrid Long-Range Mid-Infrared Hyperbolic Phonon Polariton Waveguide Using Hexagonal Boron Nitride, Di Xiong May 2019

Hybrid Long-Range Mid-Infrared Hyperbolic Phonon Polariton Waveguide Using Hexagonal Boron Nitride, Di Xiong

Theses and Dissertations

For any photonic-on-chip applications long propagation waveguides are critical. The use of plasmon polaritons for near-infrared and optical networks has been extensively studied for the purpose of achieving long propagation lengths, however, due to plasmonic polariton effects being negligible in mid- to long-wave infrared (IR) applications, phonon polaritons are required. In recent years, extensive research has been carried out on hexagonal boron nitride (h-BN), and it has been found that h-BN has naturally occurring sub-range phonon volume-constrained hyperbolic phonon polaritons (HPhPs). The numerical results in this thesis show both the long-range and short-range phonon volume polaritons modes in h-BN. A …

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Encryption Algorithms For Data Security In Local Area Network, Asmaa Essam Alhibshi May 2019

Encryption Algorithms For Data Security In Local Area Network, Asmaa Essam Alhibshi

Theses and Dissertations

Cryptography plays an important part in data and information security. An overview of cryptography is given in the paper. This paper tries to compare most commonly used encryption algorithms RSA and AES, with their performance analysis on java and C++. At first a brief introduction on types of cryptography i.e. symmetric and asymmetric encryption algorithm. Then previous work on these encryption algorithms is discussed and their performance comparison in the form of table is given. Then the objectives of this thesis is given. In chapter 3, a detailed description of ciphering algorithms, RSA, AES, TCP and UDP is provided. Chapter …

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Weak Turbulence Closures In Incompressible Magnetohydrodynamics, Augustus Antanas Azelis May 2019

Weak Turbulence Closures In Incompressible Magnetohydrodynamics, Augustus Antanas Azelis

Theses and Dissertations

In this work we apply the weak turbulence closure to the governing equation of incompressible homogeneous magnetohydrodynamics (MHD). It was originally thought that the method lacked applicability to linearly dispersive waves however MHD presents a unique exception to this notion. A perturbative scheme is used in combination with multiple scale analysis to find a dynamic equation for the wavenumber energy spectrum corresponding to weakly non-linear shear Alfv´enic turbulence. We begin by deriving an equation describing the time evolution of the Fourier transformed Els¨asser fields associated with linear propagation and non-linear interactions between counter-propagating Alfv´en waves. A cumulant hierarchy is then …

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Study Of A Crew Transfer Vehicle Using Aerocapture For Cycler Based Exploration Of Mars, Larissa Balestrero Machado May 2019

Study Of A Crew Transfer Vehicle Using Aerocapture For Cycler Based Exploration Of Mars, Larissa Balestrero Machado

Theses and Dissertations

This thesis presents the results of a conceptual design and aerocapture analysis for a Crew Transfer Vehicle (CTV) designed to carry humans between Earth or Mars and a spacecraft on an Earth-Mars cycler trajectory. The thesis outlines a parametric design model for the Crew Transfer Vehicle and presents concepts for the integration of aerocapture maneuvers within a sustainable cycler architecture. The parametric design study is focused on reducing propellant demand and thus the overall mass of the system and cost of the mission. This is accomplished by using a combination of propulsive and aerodynamic braking for insertion into a low …

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Deep Space Radiation Shelter Through Magnetic Shielding, Lauren Elizabeth Eastberg Persons May 2019

Deep Space Radiation Shelter Through Magnetic Shielding, Lauren Elizabeth Eastberg Persons

Theses and Dissertations

As human space exploration begins to reach beyond Earth for the first time in 50 years, we must prepare for the eventuality of long-duration missions outside the protection of Earth's magnetic field. In interplanetary space astronauts are exposed to highly energetic galactic cosmic radiation, most commonly in the range of 1-GeV protons. Present day shielding technologies are not sufficient to protect astronauts against such particles; as such, the following paper proposes an alternate method of creating deep space radiation shelters through the use of magnetic shielding. Using a series of circular superconducting loops arranged in the shape of a shell, …

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Damping Coefficient Sensitivity Analysis Of High Rebound Soils In Florida, Aline Franqui May 2019

Damping Coefficient Sensitivity Analysis Of High Rebound Soils In Florida, Aline Franqui

Theses and Dissertations

The dynamic response of soils is related to a damping factor, which represents the energy absorbed by the soil as the pile moves. Certain blends of fine sands, silts and clays are producing pile rebound during driving. For that reason, the objective of this thesis is to conduct a damping coefficient sensitivity analysis of high rebound soils in Florida. Forty cyclic triaxial tests from six sites in Central and Northern Florida were analyzed to evaluate damping. Two approaches were used, one based on the change in stress over time and a second based on the viscous energy absorbed per cycle. …

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Effect Of Industry Clusters And Commodity Flow Characteristics On The Selection Of Freight Transportation Modes In The United States With Advanced Econometric Approaches, Taleb Eissa Ali Eissa May 2019

Effect Of Industry Clusters And Commodity Flow Characteristics On The Selection Of Freight Transportation Modes In The United States With Advanced Econometric Approaches, Taleb Eissa Ali Eissa

Theses and Dissertations

Mode choice is an important strategic decision for shippers to carry commodities efficiently. Freight mode-choice is an important activity to develop a successful freight transportation business in the private sector and to plan for economically consistent freight transportation infrastructures in the public sector. Freight activities result from the complex interactions between different economic agents, but these relationships are commonly relaxed to account for three major agents: shippers, carriers and receivers. Furthermore, the behavior of freight choice is commonly not concentrated in one agent, but rather is divided jointly over multiple individuals and firms in a logistics process, each component of …

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Simulation Environment For Astrobee-Rings System, Tamerlan Yeleussizov May 2019

Simulation Environment For Astrobee-Rings System, Tamerlan Yeleussizov

Theses and Dissertations

The thesis analyzes a flight software of a new free flying robot Astrobee, that will change the current Synchronized Position Hold Engage Reorient Experimental Satellites (SPHERES) on International Space Station (ISS). First, the main components of the flight software were examined: Robotic Operating System (ROS), Gazebo and MATLAB. During that phase, functionalities of ROS, Gazebo and MATLAB were analyzed, and it was found how these components integrate between each other to build Astrobee flying software. Next, simulation of two Astrobees performing “in-home” and “torque” maneuvers was executed. After a successful completion of simulation, results of Astrobee’s trajectory was recorded. Then, …

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Modeling Of Hurricane-Induced Interior And Contents Damage And Associated Time-Related Expenses To Residential Buildings, Roberto Vicente Silva De Abreu May 2019

Modeling Of Hurricane-Induced Interior And Contents Damage And Associated Time-Related Expenses To Residential Buildings, Roberto Vicente Silva De Abreu

Theses and Dissertations

Hurricanes are a main cause of economic losses in many parts of the world, including the state of Florida. They affect the exterior, interior, and the contents of residential buildings. The damage of the interior can be as much as half of the total damage, but the estimation of the interior damage is still somewhat crude. Most damage models estimate interior damage as a percentage of the exterior damage, or through simple relationships, that relate the height of water ingress in the building to the interior damage. The current version of the Commercial Low-Rise Residential vulnerability model (CLR) of the …

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A Mixed Method Study On The Impact Of Industry Sponsored Projects On Senior Capstone Design Student’S Motivational Factors, Devanshi Shah May 2019

A Mixed Method Study On The Impact Of Industry Sponsored Projects On Senior Capstone Design Student’S Motivational Factors, Devanshi Shah

Theses and Dissertations

This thesis examines the change in student motivation through a yearlong senior capstone design course with respect to their choice of project type. The senior capstone design projects offered at the university fall into one of two major project types: industry sponsored and nonindustry sponsored. The students opt for either of the two major project types based on their interest and future career goals. The students were given an adapted version of Motivated Strategies for Learning Questionnaire (MSLQ) to self-identify their motivation levels by rating various questions on a 7-point Likert scale. The surveys were conducted at two different points …

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Airport Taxiway Traversal And Safety Optimization Using Combinatorics, Thore Groenlund Rasmussen May 2019

Airport Taxiway Traversal And Safety Optimization Using Combinatorics, Thore Groenlund Rasmussen

Theses and Dissertations

The demand for air travel has increased dramatically in the last decade, putting large strain on airports and their limited resources. Expanding the available resources at an airport is not always an option either due to location, budget or time. This forces the administrators of an airport system to use the limited resources as efficiently as possible. This thesis proposes a tool for air traffic controllers and pilots that can be used when planning taxiway systems. Taking inspiration from Dijkstra’s Algorithm, an algorithm is proposed to safely move aircraft from the terminal to the runway. Applying constraints to the algorithm …

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Vegetation Response To Intense Holocene Dry Events In The Andes And Amazon Basin, Majoi De Novaes Nascimento May 2019

Vegetation Response To Intense Holocene Dry Events In The Andes And Amazon Basin, Majoi De Novaes Nascimento

Theses and Dissertations

By using the natural laboratory of past climate change I ask: How resilient are extant tropical forest ecosystems to climatic forcing? Do tropical forests systems show gradualistic or threshold responses to past climate change? How do climate forcings change floristic composition? And do humans amplify or suppress the effects of natural climate variability through land use? My study is set in western Amazonia and in the eastern flank of the Andes, regions renowned for high endemism and cultural importance. The time scale of the study spans the Mid-Holocene Dry Event (MHDE, c. 9000 to 4000 years ago), arguably the most …

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Membrane Hull Technology Implemented Into A D-Collar Work Boat, Joshua Hagan May 2019

Membrane Hull Technology Implemented Into A D-Collar Work Boat, Joshua Hagan

Theses and Dissertations

Membrane Hull Technology (MHT) was initially developed for the United States Navy Rigid-Hull Inflatable Boats (RHIB) as an alternative structure design to provide weight savings and shock mitigation. MHT accomplishes this by veering away from traditional hull design and utilizing a grid like system with an increased number of longitudinal stringers and transverse frames with a significantly lower moment of inertia when compared to traditional stringers and bulkheads. The decrease in stiffness allows for increased deflection in the hull during high load events with the added benefit of shock absorption. This technology, developed by Structural Composites Inc., has been successfully …

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Experimental And Numerical Analysis Of The Drag Force On Surfboards With Different Shapes, Omar Lahlou May 2019

Experimental And Numerical Analysis Of The Drag Force On Surfboards With Different Shapes, Omar Lahlou

Theses and Dissertations

The aim of the present study is to define the hydrodynamic resistance of surfboards with different designs. Decreasing the drag acting on a board helps the surfer to attain higher surfing performances. It helps to attain higher speeds and maneuvering for the surfer. In this thesis, theoretical, experimental and computational approaches are used to explain how the drag changes with different surfboard shapes. Four surfboards with varying shapes were towed at different speeds and the resulting force was recorded. Two computational models were developed using Star CCM and Flowsquare to confirm the experimental results. The drag force on the boards …

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A Sensor Fusion And Machine Learning Approach For Predicting Signal Power Path Loss In Wireless Communications, Yunus Egi May 2019

A Sensor Fusion And Machine Learning Approach For Predicting Signal Power Path Loss In Wireless Communications, Yunus Egi

Theses and Dissertations

When it comes to Wireless Communication systems and their optimization in different environments, estimation of SPPL for different terrain models becomes one of the most tedious problems for Radio Frequency engineers. Since every terrain has their complex terrain structures and contains micro-variations, they end up with an ambiguous SPPL via scattering and absorption. Also, modern SPPL prediction models are error free since they use predefined estimation parameters for classified terrain model. Sometimes, terrain-related estimation errors may cause over undesirable SPPL level which is much larger than 5% tolerance error. To avoid this problem, one can benefit from 3D map of …

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Rapidscat Backscatter Measurements Calibration, Ruaa Alsabah May 2019

Rapidscat Backscatter Measurements Calibration, Ruaa Alsabah

Theses and Dissertations

Scatterometers are microwave radars deployed to estimate global wind speeds and directions over sea surface by measuring Normalized Radar Cross Section (σᵒ) of the sea. Measured is determined by the sea surface roughness that is modulated mostly by wind, thus establishing a relationship between and wind conditions. Wind vectors are retrieved by inverting an empirical Geophysical Model Function that relates measured to a wind vector (speed and direction) and radar measurement configuration (polarization, incidence, and azimuth angle). Careful scatterometer calibration is required for accurate wind retrieval. RapidScat is a National Aeronautics and Space Administration (NASA) Ku-Band scatterometer that was operated …

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Detecting Conflicts Among Autonomous Devices In Smart Homes, Fahd Alharithi May 2019

Detecting Conflicts Among Autonomous Devices In Smart Homes, Fahd Alharithi

Theses and Dissertations

Emerging technologies such as Internet-of-Things, sensors, and communication networks have been introduced into traditional homes to offer a wide range of smart home services to simplify home appliances or home care and enhance people’s lifestyles. Currently, the smart home system has been integrated with various features of the production line and equipped with multiple sensors and actuators to meet home occupants specifications by setting customized user policies. These days home automation systems have become widely adopted. When privileged users interact with a smart home system, their intents of using this system are probable to be various, which might lead to …

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Wavelet–Based Functional Data Analysis For Classification And Change Point Detection, Nenad Mijatovic May 2019

Wavelet–Based Functional Data Analysis For Classification And Change Point Detection, Nenad Mijatovic

Theses and Dissertations

Data collection and analysis, performed close to the source and transferred to other devices for different analysis, are the major paradigms of the Internet of Things (IoT). Usually, the raw data comes in the form of a time-series sequence that can be considered as functions, and as such can be examined by the functional analysis apparatus. Among others, the two major tasks in data analysis are (1) categorical signal classification and (2) change detection in signal statistical parameters. Here, we study both problems: featureless signal classification using discriminative interpolation regularized with the ℓ1 norm is performed using Classification by Discriminative …

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Weighted Aggregation Methods For Linear And Nonlinear Cluster Analysis With Applications To Cancer Research, Meshal Shutaywi May 2019

Weighted Aggregation Methods For Linear And Nonlinear Cluster Analysis With Applications To Cancer Research, Meshal Shutaywi

Theses and Dissertations

Due to advancements in data acquisition, large amount of data are collected on a daily basis. Analysis of the collected data is an important task to discover the patterns, extract the features, and make informed decisions. A vital step in data analysis is dividing the subjects (elements, individuals) in different groups based on their similarities. One way to group the subjects is clustering. Clustering methods can be divided into two categories, linear and non-linear. K-means is a commonly used linear clustering method, while Kernel K-means is a non-linear technique. Kernel K-means projects the elements to a new space using a …

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Integrated Representation And Discrimination Models For Functional Data Classification, Rana Haber May 2019

Integrated Representation And Discrimination Models For Functional Data Classification, Rana Haber

Theses and Dissertations

The modus operandi for machine learning is to map functional data to numerical summaries, filter the data, and/or subject it to global signature extractions with the objecive of building robust feature vectors that uniquely characterize each function and then proceed with training algorithms that seek to optimally partition the feature space S ⊂ Rn into labeled regions. This holds true even when the original data are functional in nature, i.e. curves or surfaces that inherently vary over a continuum such as time or space. Functional data are often reduced to summary statistics, locally-sensitive features, and global signatures with the objective …

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Two-Stage Mixed Integer Stochastic Programming And Its Application To Bond Portfolio Optimization, Nasser Aedh Alreshidi May 2019

Two-Stage Mixed Integer Stochastic Programming And Its Application To Bond Portfolio Optimization, Nasser Aedh Alreshidi

Theses and Dissertations

We consider a two-stage stochastic bond portfolio optimization problem, where an investor aims to optimize the cost of bond portfolio under different scenarios while ensuring predefined liabilities during a given planning horizon. The investor needs to optimally decide whether to buy, hold, or sell bonds based upon present market conditions under different scenarios and varying assumptions, where the scenarios are determined based on interest rates and buying prices of the bonds. Three stochastic integer programming models are proposed and applied to real-data from Saudi Sukuk (Bond) Market. The case-study results demonstrate the varying optimal decisions made to manage bond portfolio …

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Socio-Critical Mathematical Modeling And The Role Of Mathematics In Society, Antonnette Marvlette Gibbs May 2019

Socio-Critical Mathematical Modeling And The Role Of Mathematics In Society, Antonnette Marvlette Gibbs

Theses and Dissertations

Based on the socio-critical perspective of mathematical modeling this research investigated a tool termed MESH (Mathematics Expressing Society’s Hopes) designed to stimulate reflexive discussions about the role of mathematics in society. Constructivist grounded theory (Charmaz, 2014) methods were used to collect and analyze data from 27 students enrolled in two college algebra classes at a community college in the southernmost U.S. state. The research questions were: 1. How does the MESH tool stimulate reflexive discussions about the role of mathematics in society during and after the technological, mathematical, and reflection activities, respectively? 2. How do students understand the role of …

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Generalized Random Measures On Topological Spaces, Ali Hussein Mahmood Al-Obaidi May 2019

Generalized Random Measures On Topological Spaces, Ali Hussein Mahmood Al-Obaidi

Theses and Dissertations

Our work deals with classes of random measures on -compact Hausdorff spaces perturbed by stochastic processes. We render a rigorous construction of the stochastic integral of functions of two variables and show that such an integral is a random measure. We establish a new Campbell-type formula that, along with a rigorous construction of modulation, leads to the intensity of a modulated random measure. We further introduce and study a marked Poisson random measure on a - compact Hausdorff space. The underlying parameters of this measure are changing in accordance with the evolution of a stochastic process. This generalized random measure …

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Multi-Class Logical Analysis Of Data With Relaxed Patterns And Its Extension To Survival Analysis, Travaughn Coren Bain May 2019

Multi-Class Logical Analysis Of Data With Relaxed Patterns And Its Extension To Survival Analysis, Travaughn Coren Bain

Theses and Dissertations

This dissertation builds on a previously successful optimization based linear program multi-class classification method, called Logical Analysis of Data (LAD), and improves its generalization capability by introducing relaxed constraint modifications and then further extends and applies it to Survival Analysis. First, we propose the relaxed modifications onto the constraints of the mixed integer linear program (MILP) in the pattern generation phase of LAD. Our modifications are aimed at minimizing the degree of over-fitting to noise, allowing for added flexibility to widen the solution space in hopes to discover more robust classification rules. The proposed method introduces relaxed homogeneity and minimum …

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Parametric Methods For Analysis Of Survival Times With Applications To Organ Transplantation, Farag Hamad May 2019

Parametric Methods For Analysis Of Survival Times With Applications To Organ Transplantation, Farag Hamad

Theses and Dissertations

In this dissertation, we have two main objectives. First, we introduce a hybrid method to model hazard function. Different approaches have been used for modeling survival times including parametric, semi-parametric, and non-parametric models. Non-parametric and semi-parametric models are commonly used for survival time analysis due to their flexibility. However, the parametric models are in high demand because of their predictive power. A challenging task is to extend semi-parametric methods and design full parametric models for analysis of survival times by estimating a set of unknown parameters. In the proposed method, the nonparametric estimate of the survival function by Kaplan Meier …

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Tuning Of The Zero Dispersion Point For Micro Electrical Mechanical Systems, Rebekah Mercedes Blackwell May 2019

Tuning Of The Zero Dispersion Point For Micro Electrical Mechanical Systems, Rebekah Mercedes Blackwell

Theses and Dissertations

Resonant micro-electromechanical systems (MEMS) are increasingly common in applications, including inertial sensors and frequency sources. These devices operate at resonance and take advantage of their size, ability to integrate with electronics, and light damping. The performance of these devices can be improved by operation at higher vibration amplitudes, but they often begin to exhibit frequency shifts near resonance as the amplitude is increased, due to nonlinear stiffness effects. Previous works have sought to balance nonlinearities in order extend the linear dynamic range (LDR) of these resonators. The focus of this thesis is to characterize, for design purposes, another possible operating …

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Dream Team, Assemble! Strengthening Partnerships And Collaboration Across Technical And Public Services, Jeffrey M. Mortimore, Kristin Nielsen, Marlee Givens, Sofia Slutskaya, Tricia Clayton May 2019

Dream Team, Assemble! Strengthening Partnerships And Collaboration Across Technical And Public Services, Jeffrey M. Mortimore, Kristin Nielsen, Marlee Givens, Sofia Slutskaya, Tricia Clayton

University Libraries: Faculty Presentations

This presentation was given at the GIL Users Group Meeting.

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Ergodicity For The 3d Stochastic Navier-Stokes Equations Perturbed By Lévy Noise, Manil T. Mohan, K. Sakthivel, Sivaguru S. Sritharan May 2019

Ergodicity For The 3d Stochastic Navier-Stokes Equations Perturbed By Lévy Noise, Manil T. Mohan, K. Sakthivel, Sivaguru S. Sritharan

Faculty Publications

In this work we construct a Markov family of martingale solutions for 3D stochastic Navier–Stokes equations (SNSE) perturbed by Lévy noise with periodic boundary conditions. Using the Kolmogorov equations of integrodifferential type associated with the SNSE perturbed by Lévy noise, we construct a transition semigroup and establish the existence of a unique invariant measure. We also show that it is ergodic and strongly mixing.
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