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Full-Text Articles in Engineering

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 …


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 …


Lateral And Torsional Seismic Vibration Control For Torsionally Irregular Buildings, Osman Akyürek May 2019

Lateral And Torsional Seismic Vibration Control For Torsionally Irregular Buildings, Osman Akyürek

Theses and Dissertations

During strong earthquakes or wind gusts, it is likely that buildings with torsional irregularity in the plan have an can be seriously damaged, partially collapsed or fully collapsed. This is because Torsionally Irregular Buildings (TIBs) may have significant aerodynamic torsion loads that increase the eccentricity between the center of mass and the center of rigidity, especially in dominant torsion modes. For this reason, torsion leads to excessive increase in lateral motions when dynamic loads excite the buildings. Torsional irregularity is one of the main failure causes during strong dynamic excitations due to earthquakes or wind gusts. Ignoring torsional irregularity in …


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. …


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 …


Taxonomy And Abstraction Of The On-Demand Mobility Aviation System For Smart Cities, Wancheng Dai May 2019

Taxonomy And Abstraction Of The On-Demand Mobility Aviation System For Smart Cities, Wancheng Dai

Theses and Dissertations

The on-demand mobility aviation system is a new paradigm providing aircraft-based point-to-point transportation services to travelers in urban and suburban areas. Many consider it as the next revolution in intelligent transportation systems. Since it does not require pre-scheduling and vehicles travel at high speed, travel times are dramatically decreased, which overcomes issues of the current ground transportation system, improves travel times and level of service, increases productivity and creates new business models. Likewise, it is envisioned to generate positive environmental outcomes. Since this is a new and unique mode of intelligent transportation, few is known about its potential success and …


Thermal Gradient Characterization And Control In Micro-Fabricated Gas Chromatography Systems, Austin Richard Foster May 2019

Thermal Gradient Characterization And Control In Micro-Fabricated Gas Chromatography Systems, Austin Richard Foster

Theses and Dissertations

In order to make gas chromatography (GC) more widely accessible, considerable effort has been made in developing miniaturized GC systems. Thermal gradient gas chromatograpy (TGGC), one of the heating methods used in GC, has recieved attention over the years due to it's ability to enhance analyte focusing. The present work seeks to develop high performance miniaturized GC systems by combining miniaturized GC technology with thermal gradient control methods, creating miniaturized thermal gradient gas chromatography (µTGGC) systems. To aid in this development a thermal control system was developed and shown to successfully control various µTGGC systems. DAQ functionality was also included …


A Relationship Between The Strengths Of Type N Cubic Mortar Specimens And In-Situ Mortar, Michael Scott Reynolds May 2019

A Relationship Between The Strengths Of Type N Cubic Mortar Specimens And In-Situ Mortar, Michael Scott Reynolds

Theses and Dissertations

The compressive strength of mortar is typically determined using the American Societyfor Testing and Materials (ASTM) standard method using 2 inch cubes which are compressed tillfailure. There is however a disparity between the compressive strengths of mortar cubes, and insitumortar. This disparity is a result of the differences in thickness, aspect ratio, curingconditions, water content, and confinement between mortar cubes and mortar joints. While thesedifferences lead to mortar joints being stronger than mortar cubes, a relationship between theirstrengths is desired.Two less-common mortar strength tests were used to determine more accurately thecompressive strength of in-situ mortar. The results of both tests …


Point Cloud Based Relative Navigation For Small Satellite Rendezvous, Branden William Blackwell May 2019

Point Cloud Based Relative Navigation For Small Satellite Rendezvous, Branden William Blackwell

Theses and Dissertations

The thesis describes the development and testing of a point cloud based relative navigation sensor. The objective of this research is to provide a low cost, lightweight, low power, and low volume alternative to established rendezvous sensors , in order to enable small satellites to conduct missions such as in-space inspection, on-orbit servicing, and space debris removal. The sensor system must be able to provide relative position and orientation data to a control system independent of the cooperation of the target spacecraft or object. This is done using commercially available hardware (Microsoft Kinect v2) and an open source C++ library …


Application Of The Gradient Projection Method To An Optimal Control Problem In Quantum Biology, Rashad Abdulla May 2019

Application Of The Gradient Projection Method To An Optimal Control Problem In Quantum Biology, Rashad Abdulla

Theses and Dissertations

Quantum biology is an emerging field which seeks to understand and analyze the effects of quantum mechanical phenomena on biological systems. One such phenomenon is the formation of radical pairs, compounds which exist in a quantum superposition of two states until they collapse into one or the other. The probability of the collapse into a preferred state can be calculated from the Schrödinger equation, and is in fact dependent on external magnetic fields. This project utilizes principles of mathematical optimal control and quantum biology to determine the precise sequence of magnetic field pulses that maximize the probability of achieving the …


Unified Model Combining The Boundary Conditions Encountered At The Input, The Carrier Optical Fiber And The Output In Spatially Multiplexed Optical Communication Channels, Gregory Lewis Lovell May 2019

Unified Model Combining The Boundary Conditions Encountered At The Input, The Carrier Optical Fiber And The Output In Spatially Multiplexed Optical Communication Channels, Gregory Lewis Lovell

Theses and Dissertations

Spatial domain multiplexing allows for expansion of optical fiber data rates by utilizing the spatial dimensions within the fiber. One form of this multiplexing method utilizes oblique input angles to generate ring-like spatial modes within the optical fiber core. This radial based spatial multiplexing (rSDM) is compatible with single core fibers and conventional optical fiber systems. As rSDM has been shown to be independent of wavelength, rSDM channels allow for adaption of wavelength division multiplexing, and has been experimentally shown to be capable of improving optical fiber data rates by at least an order of magnitude. Current research into rSDM …


Drone Path Scheduling For Data Gathering In Disaster Effected Environments, James Bologna May 2019

Drone Path Scheduling For Data Gathering In Disaster Effected Environments, James Bologna

Theses and Dissertations

Creative networks in a disaster effected area have been a concern for a long time. With the innovation of flying ad hoc networks the problem can be tackled from a more practical standpoint. The use of low altitude drones equipped with wireless transmission and receiving capability can be used under the circumstances to enable ad-hoc communication. Drone coordination and route planning is a critical consideration when determining how to gather data from ground nodes, since the drones are constrained by limited battery capacity. In this research, we set out to explore a wide range of policies for determining the trajectories …


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 …


System Level Performance Evaluation Of 60 Ghz Downlink Under Different Beamforming And Scheduling Methods, Monera Elhashmi M Salah May 2019

System Level Performance Evaluation Of 60 Ghz Downlink Under Different Beamforming And Scheduling Methods, Monera Elhashmi M Salah

Theses and Dissertations

The research in millimeter-wave (mm-wave) area is of special interest to the upcoming fifth generation (5G) communications. The 60 GHz band is one of the most attractive 5G bands. That is due to the abundantly available spectrum, higher achievable throughput, and lower latency when compared to the conventional 4G bands. This research addresses the 60 GHz system level performance evaluation for cellular downlink transmission in an outdoor environment. Using a custom system level simulator, different parameters associated with the mm-wave communication system are predicted. These parameters include path loss (PL), signal-to-noiseplus-interference-ratio (SINR), number of antenna elements and several arrays implementations. …


Ue Based Performance Evaluation Of 4g Lte Network, Hazza Saif Saeed Alshamisi May 2019

Ue Based Performance Evaluation Of 4g Lte Network, Hazza Saif Saeed Alshamisi

Theses and Dissertations

In the past ten years, we have witnessed an increase in demand for mobile services as we have come to depend more and more on mobile phones as an indispensable part of everyday life. And not merely for making phone calls or sending text messages, but also for services such as games, mobile banking, streaming videos and making video calls. These mobile applications consume far more data than simple voice calls. Reflecting what an end user experiences when using a mobile device is an aspect that has not yet been properly catered for. The LTENetScan framework introduced a novel method …


Energy, Exergy And Economic Analysis Of A Micro-Cchp System, Ganesh Vinayak Doiphode May 2019

Energy, Exergy And Economic Analysis Of A Micro-Cchp System, Ganesh Vinayak Doiphode

Theses and Dissertations

Combined cooling, heating and power generation (CCHP) systems can be utilized for commercial or multi-family residential buildings as efficient and reliable means to satisfy building power requirements and thermal loads. In the present study, a CCHP system consist of a Bryton cycle, an Organic Rankine cycle (ORC) and an absorption Ammonia-water cycle is considered. A detailed model is developed via MATLAB to assess the performance of the considered cycle from energy, exergy and economic perspectives. Appropriate ranges for inputs are considered and the first law efficiency, second law efficiency and ECOP of the cycle are determined as 77.17%, 33.18% and …


Hardware-In-The-Loop Testbed For The Dynamics Of Spacecraft Rendezvous And Capture, Stephen Thiam Choy Kwok Choon May 2019

Hardware-In-The-Loop Testbed For The Dynamics Of Spacecraft Rendezvous And Capture, Stephen Thiam Choy Kwok Choon

Theses and Dissertations

As more satellites are launched into orbit, the amount of space debris objects and defunct satellites in orbit that pose a risk to existing operational space systems is expected to grow. In addition, the risk of collision with defunct systems and space debris increase operational fuel cost for active satellites that have to perform avoidance maneuvers. When a satellite’s propulsion or attitude navigation system malfunction, this may cause the satellite to become defunct, potentially becoming a risk to other active space systems. A way to counter defunct satellite systems, is through robotic on-orbit servicing and active space debris removal as …


A Game Theory Motivated Approach To Analyzing Modularity In Automotive Systems, David John Thiess Jr. May 2019

A Game Theory Motivated Approach To Analyzing Modularity In Automotive Systems, David John Thiess Jr.

Theses and Dissertations

This paper examines the effect of integrated and modular design on consumers and manufacturers and seeks to determine if there is an optimal design that benefits both. Some consumers perceive the automotive industry to design vehicles with only the company’s benefit in mind, rather than the desires of the consumer. However, the automotive industry seeks to please consumers, while minimizing the cost of production. A game-theoretic based model was developed that was used to determine if there existed a level of modularity for a system that optimized for both the manufacturer and consumer. The game model consisted of two players, …


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 …


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 …


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 …


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 …


Calibration Of The Rapidscat Microwave Brightness Temperature, Ali Al-Sabbagh May 2019

Calibration Of The Rapidscat Microwave Brightness Temperature, Ali Al-Sabbagh

Theses and Dissertations

NASA RapidScat is the first satellite scatterometer that flown in non-Sun-synchronous orbit. Its unique orbit enabled collocated measurements with multiple satellite remote-sensing instruments that usually fly in Sun-synchronous orbits. RapidScat’s primary mission was retrieval of global ocean wind vectors from normalized radar backscatter measurements. The instrument operated onboard the International Space Station between September 2014 and August 2016 covering latitude range between ±51.6ᵒ . To serve as a cross-calibration reference with other instruments, RapidScat must be internally calibrated. This dissertation presents the first radiometric calibration of RapidScat brightness temperature measurements and describes the process that combines RapidScat’s active/passive mode, simultaneously …


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 …


The Detection And Prevention Of Cascading Failure In Power Systems: A Real-Time Solution For Intentional Controlled Islanding, Faycal Znidi Apr 2019

The Detection And Prevention Of Cascading Failure In Power Systems: A Real-Time Solution For Intentional Controlled Islanding, Faycal Znidi

Theses and Dissertations

Intentional controlled islanding (ICI), also referred as controlled system separation or system splitting, has been proposed as an effective corrective control action to help detect, prevent and mitigate the risk and spread of the cascading failures. A practical controlled islanding separation scheme needs to address two critical problems: where to island i.e., the splitting points to form sustainable islands and when to island i.e., Islanding time. This dissertation examines the causes and mechanism of power system cascading outages and develops new approaches to help detect, prevent and mitigate the risk and spread of these cascading failures. Four effective solutions: weighted …


Design, Fabrication And Validation Of A Hand-Wore Device For Assisted Object Grasping For The Visually Impaired, Xiaoping Liu Apr 2019

Design, Fabrication And Validation Of A Hand-Wore Device For Assisted Object Grasping For The Visually Impaired, Xiaoping Liu

Theses and Dissertations

Grasping a target object is very challenging to a visually impaired individual due to vision loss. An object grasping task can be divided into three sub-tasks: detecting the target ob-ject, maintaining hand-object alignment while approaching the object, and taking a hold of it. Vision loss makes the first two sub-tasks impossible. To help a visually impaired per-son re-gain the capability in performing the two sub-tasks, a hand-worn assistive device is designed. The device consists of control and visual guidance. Control involves an exo-skeleton mechanism worn by user’s right hand. The mechanism, driven by two micro-motors, drags the thumb to move …


Development And Validation Of A Vibration-Based Sound Power Measurement Method, Cameron Bennion Jones Apr 2019

Development And Validation Of A Vibration-Based Sound Power Measurement Method, Cameron Bennion Jones

Theses and Dissertations

The International Organization for Standardization (ISO) provides no vibration-based sound power measurement standard that provides Precision (Grade 1) results. Current standards that provide Precision (Grade 1) results require known acoustic environments or complex setups. This thesis details the Vibration Based Radiation Mode (VBRM) method as one approach that could potentially be used to develop a Precision (Grade 1) standard. The VBRM method uses measured surface velocities of a structure and combines them with the radiation resistance matrix to calculate sound power. In this thesis the VBRM method is used to measure the sound power of a single-plate and multiple plate …


Analiza E Humbjeve Në Sistemet Elektroenergjetike, Flakrim Krasniqi Apr 2019

Analiza E Humbjeve Në Sistemet Elektroenergjetike, Flakrim Krasniqi

Theses and Dissertations

Sektori i energjisë në Kosovë konsiderohet si një ndër sektorët me potencialin më të madh të zhvillimit. Kjo bazuar në resurset e mëdha energjetike të vendit, në traditën pothuajse gjysmëshekullore dhe në nevojat gjithnjë në rritje për energji të ekonomisë vendore por edhe të vendeve për rreth. Rrjedhimisht, sektori i energjisë do të duhej të paraqiste një ndër shtyllat kryesore të ekonomisë së vendit. Mirëpo, problemet e trashëguara nga periudha e paraluftës si dhe periudha e tranzicionit deri në krijimin e institucioneve të Pavarura të Republikës së Kosovës, kanë ndikuar performanca e këtij sektori të jetë ende larg nga performanca …


Druri Si Material Ndërtimi, Arbërie Kurrumeli Apr 2019

Druri Si Material Ndërtimi, Arbërie Kurrumeli

Theses and Dissertations

Për qëndrueshmërinë afatgjate të punimeve me dru, ndërtuesit dhe përdoruesit që merren me këtë lëndë duhet të njohin saktësisht vetite e drurit. Druri është një material organik, higroskopik dhe anizotropik. nese perdoret ne elementet e ndertimit, ai mund te luaj role strukturore, funksionale dhe estetike ne te njejten kohe. Perdorimi i tij eshte i madh ne saje te dimensionimit te qendrueshem te objekteve te drurit nga kendveshtrimet mjedisore, ekonomike dhe sociale. Eshte mundur të ndërtohet një shtëpi e rehatshme duke përdorur vetëm produkte prej druri. Me materiale të tjera,kjo është pothuajse e pamundur. Por druri ka disa disavantazhe gjithashtu. Perdorimi …


Understanding The Strain Localization And Progressive Damage Growth At The Free-Edge Of Composite Laminates Using Digital Image Correlation, Addis Tessema Apr 2019

Understanding The Strain Localization And Progressive Damage Growth At The Free-Edge Of Composite Laminates Using Digital Image Correlation, Addis Tessema

Theses and Dissertations

Understanding the mechanics of Fiber Reinforced Composites (FRC) that guide the design and optimization of laminate structures, have attracted numerous researchers. For the last five decades, various analytical and numerical models have been developed to understand the damage and failure mechanisms in FRC. For long, Classical laminate plate theory (CLPT) has majorly been used as a theoretical guide in the design of composite structures. The CLPT framework is developed based on the consideration of an infinitesimal wide plate that depicts a planar stress condition. Thus, as it considers only the planar stresses, the out of plane interlaminar stresses are absent …