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Full-Text Articles in Engineering

Investment Plan Against Malicious Attacks On Power Networks: Multilevel Game-Theoretic Models With Shared Cognition, Hamzeh Davarikia Aug 2017

Investment Plan Against Malicious Attacks On Power Networks: Multilevel Game-Theoretic Models With Shared Cognition, Hamzeh Davarikia

Theses and Dissertations

The work reported in this thesis aims at developing a practical tool for utility transmission planners to protect power network from potential attacks. To efficiently address the problem, we propose a new formulation for defender which has a promising result than its counterpart. Moreover, the optimum defending strategy in power network is modeled which return the best protecting strategy based on the defender resources. Going beyond the common approaches in literature, defender deception is mathematically formulated by releasing misinformation about his plan in the shared cognition based model. The problems are formulated as tri-level mixed-integer non-linear programming and exact linearization …


Crack Healing In 304l Stainless Steel Using Additive Manufacturing And Friction Stir Processing (Fsp), Cameron Scott Gygi Aug 2017

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 …


Algan/Gan Hemt By Magnetron Sputtering System, Roman Garcia Perez Aug 2017

Algan/Gan Hemt By Magnetron Sputtering System, Roman Garcia Perez

Theses and Dissertations

In this thesis, the growth of the semiconductor materials AlGaN and GaN is achieved by magnetron sputtering for the fabrication of High Electron Mobility Transistors (HEMTs). The study of the deposited nitrides is conducted by spectroscopy, diffraction, and submicron scale microscope methods. The preparation of the materials is performed using different parameters in terms of power, pressure, temperature, gas, and time. Silicon (Si) and Sapphire (Al2O3) wafers are used as substrates. The chemical composition and surface topography of the samples are analyzed to calculate the materials atomic percentages and to observe the devices surface. The instruments used for the semiconductors …


Development Of Lower Rio Grande River Water Quality Transportation Numerical Model For Bi-National River Management, Jose O. Gonzalez Aug 2017

Development Of Lower Rio Grande River Water Quality Transportation Numerical Model For Bi-National River Management, Jose O. Gonzalez

Theses and Dissertations

Traditionally, water quality modelling has focused on modelling individual water bodies. However, water quality management problems must be analyzed at the larger scale to include influences from various water bodies that are interconnected. This paper provides a study on the hydrologic and quality transportation calculation by developing a hydrodynamic (unsteady state) channel routing model using a water-balanced approach. A one dimension Lagrangian river model was developed and applied to the 210 plus miles for the lower Rio Grande River Basin from the Falcon Dam to the head water of Brownsville that pours onto the Gulf of Mexico. This model can …


Multi-Functional System For Biomedical Application Using Ac Electrokinetics, Rakesh Guduru Aug 2017

Multi-Functional System For Biomedical Application Using Ac Electrokinetics, Rakesh Guduru

Theses and Dissertations

Manipulation of fluids in a small volume is often a challenge in the field of Microfluidics. While many research groups have addressed this issue with robust methodologies, manipulating fluids remains a scope of study due to the ever-changing technology (Processing Tools) and increase in the demand for “Lab-On-a-Chip” devices in biological applications. This thesis peruses the flow pattern of the orthogonal electrode pattern and circular electrode providing, examples of the flow patterns and the process micromixing. Characteristics of a multifunctional system were demonstrated using orthogonal electrode and circular electrode patterned device. Conductivity of the fluids were chosen such they reflect …


Characterization Of Lift And Drag On Two Dimensional Airfoils With And Without Sinusoidal Leading Edges, Gregorio I. Acosta Aug 2017

Characterization Of Lift And Drag On Two Dimensional Airfoils With And Without Sinusoidal Leading Edges, Gregorio I. Acosta

Theses and Dissertations

An experimental investigation was taken on a 63-021 NACA airfoil, to characterize lift and drag and how the effects of sinusoidal leading edges affect the aerodynamic properties. A theoretical model is also purposed by implementing a perturbation on thin-airfoil theory.

Two sets of airfoils were machined and tested inside a low-speed open circuit wind tunnel. Data from a pressure scanner and particle image velocity will give an insight of how the modified leading edges affect the aerodynamic properties. A Fourier series expansion was used to solve for the lifting-line model, by use of thin-airfoil theory and complex number theory.


Cell-Free Synthesis Of Proteins With Unnatural Amino Acids: Exploring Fitness Landscapes, Engineering Membrane Proteins And Expanding The Genetic Code, Song Min Schinn Aug 2017

Cell-Free Synthesis Of Proteins With Unnatural Amino Acids: Exploring Fitness Landscapes, Engineering Membrane Proteins And Expanding The Genetic Code, Song Min Schinn

Theses and Dissertations

Unnatural amino acids (uAA) expand the structural and functional possibilities of proteins. Numerous previous studies have demonstrated uAA as a powerful tool for protein engineering, but challenges also remain. Three notable such challenges include: (1) the fitness of uAA-incorporated proteins are difficult to predict and time-consuming to screen with conventional methods, (2) uAA incorporation in difficult-to-express proteins (e.g. membrane proteins such as G-protein coupled receptors) remain challenging, and (3) the incorporation of multiple types of uAA are still limited. In response, we pose cell-free protein synthesis (CFPS), a rapid and versatile in vitro expression system, as a platform to explore …


Performance-Based Liquefaction Triggering Analyses With Two Liquefaction Models Using The Cone Penetration Test, Alex Michael Arndt Aug 2017

Performance-Based Liquefaction Triggering Analyses With Two Liquefaction Models Using The Cone Penetration Test, Alex Michael Arndt

Theses and Dissertations

This study examines the use of performance-based engineering in earthquake liquefaction hazard analysis with Cone Penetration Test data (CPT). This work builds upon previous research involving performance-based liquefaction analysis with the Standard Penetration Test (SPT). Two new performance-based liquefaction triggering models are presented herein. The two models used in this liquefaction analysis are modified from the case-history based probabilistic models proposed by Ku et al. (2012) and Boulanger and Idriss (2014). Using these models, a comparison is made between the performance-based method and the conventional pseudo-probabilistic method. This comparison uses the 2014 USGS probabilistic seismic hazard models for both methods. …


High Throughput Analysis Of The Penetration Of Iron Oxide/Polyethylene Glycol Nanoparticles Into Multicellular Breast Cancer Tumor Spheroids, Jonathan Robert Gabriel Jul 2017

High Throughput Analysis Of The Penetration Of Iron Oxide/Polyethylene Glycol Nanoparticles Into Multicellular Breast Cancer Tumor Spheroids, Jonathan Robert Gabriel

Theses and Dissertations

The purpose of this study was to design and optimize a system for the high-throughput analysis of multicellular tumor spheroids (MCTS), and validate the system through the study of a complex biological model. The system was successfully created and optimized, allowing the histological recovery of MCTS at rates up to 90% for microarrays of 24-spheroids. Arrays of 96-spheroids were recovered at rates up to 86%. The system was used to study the penetration of 5k Da-polyethylene coated superparamagnetic iron-oxide nanoparticles (5k-PEG SPIONs) into HTB-126 breast cancer spheroids cultured to a mean diameter of 486 micrometer (± 25.2 micrometer). Results were …


Blending And Mixed Variational Principles To Overcome Locking Phenomena In Isogeometric Beams, Kyle Dennis Richardson Jul 2017

Blending And Mixed Variational Principles To Overcome Locking Phenomena In Isogeometric Beams, Kyle Dennis Richardson

Theses and Dissertations

Two methods for overcoming locking phenomena in isogeometric beams are presented. The first method blends the rotation of a Timoshenko beam with the rotation of a Bernoulli beam to produce realistic displacements in straight beams. The second method uses mixed variational principles, specifically the Hu-Washizu Principle, to produce realistic displacements as well as realistic strains without post-processing.


Improved Leaky-Mode Waveguide Spatial Light Modulators For Three Dimensional Displays, Scott Alexander Gneiting Jul 2017

Improved Leaky-Mode Waveguide Spatial Light Modulators For Three Dimensional Displays, Scott Alexander Gneiting

Theses and Dissertations

This thesis improves on the design of the leaky-mode spatial light modulator, LMW-SLM, presented by Dr. Smalley[1]. Improvements include: input coupling gratings, a pulsed laser input, output coupling gratings, and a 3D printed adjustable module for the stabilization of critical alignments. First, input coupling gratings reduce the cost of the LMW-SLM from $500 to around $2, a drop in cost of over two orders of magnitude. This enables multiple modulators to be used in a single display and allows for an inexpensive modular design to be created. Second, a pulsed laser input allows for image creation without the use of …


Vetë-Shërimi I Betonit Me Anë Të Baktereve, Endrit Koçinaj Jul 2017

Vetë-Shërimi I Betonit Me Anë Të Baktereve, Endrit Koçinaj

Theses and Dissertations

Betoni është materiali më i përdorur në botën e ndërtimit. Rezistenca e lartë në shtypje dhe çmimi i lirë e bëjnë atë shumë të kërkuar në botën e ndërtimit. Humbja e vetive kryesore të tij dhe paraqitja e plasaritjeve janë probleme që kërkojnë studime të vazhdueshme. Kjo temë studion përmirësimin e performancës së betonit me ndihmën e baktereve të ndryshme pas paraqitjes së plasaritjeve. Përdorimi i baktereve në beton, ka arritur në zhvillimin e një betoni të posaçëm që arrinë t’i mbyll plasaritjet vetëvetiu me aktivizimin e këtyre baktereve. Hulumtimet e deri tanishme na kanë dhënë rezultate shumë të mira. …


Projekti I Shfrytëzimit Të Gëlqerorëve Në Vendburimin ,,Gryka”-Shalë, Armend Aliu Jul 2017

Projekti I Shfrytëzimit Të Gëlqerorëve Në Vendburimin ,,Gryka”-Shalë, Armend Aliu

Theses and Dissertations

Punimi me titull “Projekti i shfrytëzimit të gëlqerorëve në vendburimin Gryka”-Shalë, përshkruan më hollësisht projektin e vendburimi të gëlqeroreve me pikat gjeodezike sipas hartës së situacioni. Ky guri gëlqerore që nxirren nga ky vendburim, është i nevojshëm për punët ndërtimore në ndërtimtari, posaçërisht në infrastrukturën e rrugëve dhe punimeve tjera sipas kërkesave të tregut. Në ketë punim kemi marre për bazë, analizën e mineralit, testimet gjeomekanike, karakteristikat gjeolo-inxhinierike, kualitetin dhe rezervat, përshkrimin teknik, këndet e shkalleve të gurores sipas standardeve Gjeoteknike, Faktorin e sigurisë Fs ngarkimin dhe transportin, masat mbrojtëse, pjesën ndërtimore, rregullimin e punishtes, trajtimin e ujërave sipërfaqësorë dhe …


Prodhimet Nga Argjila Të Prodhuesit “Brickos”, Vigan Kastrati Jul 2017

Prodhimet Nga Argjila Të Prodhuesit “Brickos”, Vigan Kastrati

Theses and Dissertations

Kjo temë ka për qëllim shtjellimin e punëve dhe proceseve që marrin pjesë në prodhimin e materialeve argjilore, saktësisht bllokave në fabrikën “BRICKOS”, e cila ndodhet në Kamenicë.Si fillim kemi shtjelluar pjesën teorike të materialeve argjilore, të cilën e kemi marrë nga literatura të ndryshme të cilat janë të cekura në fund tek referencat.Më pas kemi filluar me punën konkrete e cila është zhvilluar në fabrikën e lartë cekur, ku me ndihmën e teknologut të asaj fabrike kam fituar njohuri të shumta mbi zhvillimin e proceseve të prodhimit të produkteve argjilore. Ne aty kemi përcjellë të gjitha proceset teknologjike që …


Optimal Control Methods For Missile Evasion, Ryan W. Carr Jul 2017

Optimal Control Methods For Missile Evasion, Ryan W. Carr

Theses and Dissertations

Optimal control theory is applied to the study of missile evasion, particularly in the case of a single pursuing missile versus a single evading aircraft. It is proposed to divide the evasion problem into two phases, where the primary considerations are energy and maneuverability, respectively. Traditional evasion tactics are well documented for use in the maneuverability phase. To represent the first phase dominated by energy management, the optimal control problem may be posed in two ways, as a fixed final time problem with the objective of maximizing the final distance between the evader and pursuer, and as a free final …


Consumers’ Willingness To Fly In Augmented Cognition Equipped Aircraft, Eric Schanafelt Jul 2017

Consumers’ Willingness To Fly In Augmented Cognition Equipped Aircraft, Eric Schanafelt

Theses and Dissertations

Current advancements in the field of Augmented Cognition have garnered attention from the aviation industry. Equipping flight management systems with Augmented Cognition is a possibility in the near future as the result of recent computing breakthroughs. The purpose of this study was to determine to what extent gender, country of origin and condition of Augmented Cognition affect consumers willingness to fly. To further understand the consumer's decision-making process the participant’s willingness to fly measured through affect (emotion), represented through the six universal facial expressions, (anger, disgust, fear, happiness, sad, and surprise) (Ekman & Friesen, 1971). This study surveyed participants from …


A Graphical Representation Of Exposed Parallelism, Gustavo Enrique Rodriguez Villamizar Jul 2017

A Graphical Representation Of Exposed Parallelism, Gustavo Enrique Rodriguez Villamizar

Theses and Dissertations

Modern-day microprocessors are measured in part by their parallel performance. Parallelizing sequential programs is a complex task, requiring data dependence analysis of the program constructs. Researchers in the field of parallel optimization are working on shifting the optimization effort from the programmer to the compiler. The goal of this work is for the compiler to visually expose the parallel characteristics of the program to researchers as well as programmers for a better understanding of the parallel properties of their programs. In order to do that we developed Exposed Parallelism Visualization (EPV), a statically-generated graphical tool that builds a parallel task …


High-Voltage Measurements Using Slab-Coupled Optical Sensors, Legrand Jared Shumway Jul 2017

High-Voltage Measurements Using Slab-Coupled Optical Sensors, Legrand Jared Shumway

Theses and Dissertations

This work highlights slab coupled optical sensors (SCOS) and their ability to measure high voltages. Although other high voltage measurement techniques exist, most of these techniques are electrical devices and are therefore more susceptible to stray ground currents and other electromagnetic interferences (EMI), which may cause signal distortion. Optical sensors are less susceptible to such interferences and these sensors, such as the Pockels cell, have been used in measuring high voltage. SCOS offer an alternative method of measuring high voltage optically. Consisting of an optical fiber and an electro-optic slab waveguide, SCOS have the advantage of being very small in …


Quick Shear Testing Of Aggregate Base Materials Stabilized With Geogrid, Rawley Jack Selk Jul 2017

Quick Shear Testing Of Aggregate Base Materials Stabilized With Geogrid, Rawley Jack Selk

Theses and Dissertations

The objective of this research was to apply a previously recommended laboratory testing protocol to specific aggregate base materials that are also the subject of ongoing full-scale field testing. The scope of this research involved three aggregate base materials selected from three sites where full-scale field testing programs have been established. The first and second field sites included five different geogrid types, categorized as either biaxial or triaxial, in a singlelayer configuration, while the third site included only the triaxial geogrid type in either a singleor double-layer configuration. Geogrid-stabilized and unstabilized control specimens were evaluated using the American Association of …


A Comprehensive Coal Conversion Model Extended To Oxy-Coal Conditions, Troy Michael Holland Jul 2017

A Comprehensive Coal Conversion Model Extended To Oxy-Coal Conditions, Troy Michael Holland

Theses and Dissertations

CFD simulations are valuable tools in evaluating and deploying oxy-fuel and other carbon capture technologies either as retrofit technologies or for new construction. However, accurate predictive simulations require physically realistic submodels with low computational requirements. In particular, comprehensive char oxidation and gasification models have been developed that describe multiple reaction and diffusion processes. This work extends a comprehensive char conversion code (the Carbon Conversion Kinetics or CCK model), which treats surface oxidation and gasification reactions as well as processes such as film diffusion, pore diffusion, ash encapsulation, and annealing. In this work, the CCK model was thoroughly investigated with a …


Particle Deposition Behavior From Coal-Derived Syngas In Gas Turbines At Modern Turbine Inlet Temperatures, Robert Laycock Jul 2017

Particle Deposition Behavior From Coal-Derived Syngas In Gas Turbines At Modern Turbine Inlet Temperatures, Robert Laycock

Theses and Dissertations

Certain types of fuel used for combustion in land-based gas turbines can contain traces of ash when introduced into a gas turbine. Examples include synfuel, from the gasification of coal, and heavy fuel oil. When these ash particles travel through the hot gas path of the gas turbine they can deposit on turbine vanes and blades. As deposits grow, they can reduce turbine efficiency and damage turbine hardware. As turbine inlet temperatures increase, ash deposition rates increase as well.Experiments were conducted in the Turbine Accelerated Deposition Facility (TADF) at Brigham Young University to better understand ash deposition behavior at modern …


A Simple Multi-Core Functional Cache Design Simulator, Rano Mal Jul 2017

A Simple Multi-Core Functional Cache Design Simulator, Rano Mal

Theses and Dissertations

This paper presents a flexible multi-core cache memory simulator to design and evaluate memory hierarchies for general-purpose or embedded processors. The proposed simulator needs to work with Pin, which is an open-source dynamic instrumentation tool provided by Intel. The Pin intercepts the execution of instructions and generates a sequence code (traces) to feed into the simulator for any selected benchmark programs, such as SPEC2006, SPLASH2, or PARSEC. We have a plan to release this simulator as an open-source (like Pin) to support research and/or academic community for their simulation works. In addition, we expect more functions can be updated on …


Continuous Permeability Measurement During Unidirectional Vacuum Infusion Processing, David Wayne Hoagland Jul 2017

Continuous Permeability Measurement During Unidirectional Vacuum Infusion Processing, David Wayne Hoagland

Theses and Dissertations

Composite materials have traditionally been used in high-end aerospace parts and low-end consumer parts. The reason for this separation in markets is the wide gap in technology between pre-preg materials processed in an autoclave and chop strand fiberglass blown into an open mold. Liquid composite molding has emerged as a bridge between inexpensive tooling and large, technical parts. Processes such as vacuum infusion have made it possible to utilize complex layups of reinforcement materials in an open mold style set-up, creating optimal conditions for composites to penetrate many new markets with rapid innovation. Flow simulation for liquid composite molding is …


Effect Of Tannic Acid Crosslinking On The Mechanical Properties Of Collagen Scaffolds And Melanoma Cell Proliferation, Christopher J. Bridgeman Jul 2017

Effect Of Tannic Acid Crosslinking On The Mechanical Properties Of Collagen Scaffolds And Melanoma Cell Proliferation, Christopher J. Bridgeman

Theses and Dissertations

Metastatic melanoma is responsible for nearly 10,000 deaths in the United States each year. While the prognosis for patients with localized early stage melanoma cancer is good, the chances of survival for patients with late stage metastatic melanoma are only 16%. Matrix stiffness has been shown to have a profound effect on tumor metastasis for breast cancer, but little is known about its role on melanoma metastasis and progression. Similarly, the therapeutic effect of tannic acid (TA) has been extensively characterized for soft breast and leukemia cancers, but not for melanoma. The goal of the current study was to investigate …


Geometry Driven Probabilistic Models For Shape Matching, Classification And Retrieval, Mark Matthew Moyou Jul 2017

Geometry Driven Probabilistic Models For Shape Matching, Classification And Retrieval, Mark Matthew Moyou

Theses and Dissertations

Emulating human vision in a computational framework—known as computer vision—is one of the next major research areas being pursued; this emulation of vision can be viewed from a Systems Engineering perspective. The goal would be to design and develop an Intelligent Vision System built on a framework that could be tailored for specific vision applications. One of the fundamental components of vision is shape, so to design effective vision systems one needs to incorporate shape based algorithms as a core component. This dissertation progresses three facets of shape analysis algorithms: classification, retrieval and registration. Through the use of probabilistic models …


Concept Of Operations And High Level Requirements Framework For The Development Of A Computational Tool For Bridge Deterioration Analysis, Gabrielle Sue Leesman Jul 2017

Concept Of Operations And High Level Requirements Framework For The Development Of A Computational Tool For Bridge Deterioration Analysis, Gabrielle Sue Leesman

Theses and Dissertations

In developing the lifecycles of a system, maintenance and support must be considered. Associated with this portion of the life cycle are periods between needs of maintenance and the cost of each type of maintenance. Previously a few state deterioration models have been created separately to better predict these maintenance cycles for varying ages, materials, traffic flow, and environmental conditions in the deck, substructure, and superstructure of bridges. A particular analysis tool from previous studies involves the development of Markov Chain (MC) models. This paper presents a systematic process to develop MC bridge deterioration models for state/federal transportation agencies. A …


Tuning Micro-Electro-Mechanical Resonators For Maximum Dynamic Range, Joseph William Fisher Jul 2017

Tuning Micro-Electro-Mechanical Resonators For Maximum Dynamic Range, Joseph William Fisher

Theses and Dissertations

This research seeks to improve the linear dynamic range (LDR) of micro-electromechanical systems (MEMS) resonators, which are commonly used in sensing and timing applications. We address specifically the need for devices whose response is relatively large yet remains single-valued near resonance. We develop and analyze a model for a class of electrostatically actuated micro structures that includes higher order electrostatic effects, thereby allowing one to determine the LDR for devices that are tuned to eliminate cubic order nonlinear effects. The inclusion of the capacitive forces produces a model that is best solved by expanding the force in a Taylor series. …


Full-Scale Testing Of Blast-Induced Liquefaction Downdrag On Driven Piles In Sand, Luke Ian Kevan Jul 2017

Full-Scale Testing Of Blast-Induced Liquefaction Downdrag On Driven Piles In Sand, Luke Ian Kevan

Theses and Dissertations

Deep foundations such as driven piles are often used to bypass liquefiable layers of soil and bear on more competent strata. When liquefaction occurs, the skin friction around the deep foundation goes to zero in the liquefiable layer. As the pore pressures dissipate, the soil settles. As the soil settles, negative skin friction develops owing to the downward movement of the soil surrounding the pile. To investigate the magnitude of the skin friction along the shaft three driven piles, an H-pile, a closed end pipe pile, and a concrete square pile, were instrumented and used to measure soil induced load …


Vivado Design Interface: Enabling Cad-Tool Design For Next Generation Xilinx Fpga Devices, Thomas James Townsend Jul 2017

Vivado Design Interface: Enabling Cad-Tool Design For Next Generation Xilinx Fpga Devices, Thomas James Townsend

Theses and Dissertations

The popularity of field-programmable gate arrays (FPGA) has grown in recent years due to their potential performance advantages over sequential software, and as a prototyping platform for application-specific integrated circuits (ASIC). Vendors such as Xilinx offer automated tool suites that can be used to program FPGAs based on a RTL description. These tool suites are sufficient forgeneral users, but they usually don't provide the opportunity to integrate custom computer-aideddesign (CAD) tools into the regular design flow. Xilinx first offered this capability in their ISE tool suite with the Xilinx Design Language (XDL). Using XDL, a Xilinx design could be extracted …


Determining H2O Vapor Temperature And Concentration In Particle-Free And Particle-Laden Combustion Flows Using Spectral Line Emission Measurements, John Robert Tobiasson Jul 2017

Determining H2O Vapor Temperature And Concentration In Particle-Free And Particle-Laden Combustion Flows Using Spectral Line Emission Measurements, John Robert Tobiasson

Theses and Dissertations

There is a growing need for the clean generation of electricity in the world, and increased efficiency is one way to achieve cleaner generation. Increased efficiency may be achieved through an improved understanding of the heat flux of participating media in combustion environments. Real-time in-situ optical measurements of gas temperature and concentrations in combustion environments is needed. Optical methods do not disturb the flow characteristics and are not subject to the temperature limitation of current methods. Simpler, less-costly optical measurements than current methods would increase the ability to apply them in more circumstances. This work explores the ability to simultaneously …