Engineering Commons^™

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

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

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

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

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 …

Scitech News Volume 71, No. 3 (2017)

Sci-Tech News

Columns and Reports

From the Editor.........................3

Division News

Science-Technology Division....5

Chemistry Division....................8

Conference Report, Marion E, Sparks Professional Development Award Recipient..9

Engineering Division................10

Engineering Division Award, Winners Reflect on their Conference Experience..15

Aerospace Section

of the Engineering Division .....18

Architecture, Building Engineering, Construction, and Design Section of the Engineering Division................20

Reviews

Sci-Tech Book News Reviews...22

Advertisements

IEEE..........................................4

Investigation Of Lattice Structures And Analysis Of Strut Geometry., Zachary D Denzik

Electronic Theses and Dissertations

This study involves the evaluation of lattice specimens fabricated using additive manufacturing as well as investigation of the influence of unit cell connection geometry. Lattice topologies of face-centered cells and body-centered cells were modeled, investigated using finite element analysis (FEA) for each specimen, manufactured using direct metal laser sintering (DMLS) with maraging steel powder, and mechanically tested. The strut diameter of each topology was altered to yield four different mass reductions from a solid cube, ranging from 55%-90% mass reduction. Three iterations of 1000mm³ lattice specimens were investigated. The first iteration consisted 0.5mm plates on the top and bottom …

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 …

Academic Packing For Commercial Fpga Architectures, Travis D. Haroldsen

Theses and Dissertations

With a few exceptions, academic packing algorithms for FPGAs are typically applied solely to theoretical architectures. This has allowed the algorithms to focus on the basic components of packing while abstracting away many of the details dictated by real hardware. As commercially available FPGAs have advanced, however, the academic algorithms and architectures have diverged significantly from their commercial counterparts. In this dissertation, the RapidSmith 2 framework is presented. This framework accurately reflects the architecture of Xilinx FPGAs and provides support for integrating custom tools into the commercial CAD tools. Using this framework, the RSVPack packing algorithm is implemented. The RSVPack …

Development Of A Simplified Performance-Based Procedure For The Assessment Of Liquefaction-Induced Settlements Using Liquefaction Loading Maps, Braden Michael Error

Theses and Dissertations

Liquefaction-induced settlement can cause extensive damage to infrastructure. Quantifying the amount of settlement that may occur after an earthquake is crucial to seismic design. The Pacific Earthquake Engineering Research (PEER) Center developed performance-based earthquake engineering (PBEE) as a probabilistic framework to characterize the risks associated with a seismic event. When applied to liquefaction-induced settlement, the PBEE framework provides a more complete and accurate representation of liquefaction hazard than other more conventional evaluation methods. Performance-based engineering is not widely used in practice, however, due to its complexity. In an attempt to make performance-based engineering methods more accessible to engineers for routine …

Mathematical Model And Experimental Verification Of Spatially Multiplexed System Using Ray Theory And Modified Laguerre Gaussian Beams, Saud Alanzi

Theses and Dissertations

Spatial/Space Division Multiplexing (SDM) is based on a channel spacing technique in optical fibers that has the potential to inspire a revolution in optical communications. This patented technique provides a method to launch, transport, and detect two or more optical channels that operate at exactly the same wavelength inside a single multimode optical fiber. In addition, the patented technique added a new dimension and a new degree of photon freedom to the existing fiber multiplexing techniques and complements Time Division Multiplexing (TDM) and Wavelength Division Multiplexing (WDM). As a result, the bandwidth of existing and new optical fiber systems maybe …

Improving Crash Safety Of Jet Dragsters Through Modeling And Analysis, Paige Leigh Sanchez

Theses and Dissertations

The objective of this thesis was to analyze how additional foam implementation in a jet dragster driver’s compartment can improve driver safety in the case of an accident. This analysis was divided into two sections: a crash simulation analysis and a base excitation mass-spring-damper model analyzing foam behavior. The jet dragster crash simulation modeled, reflected a Larsen Motorsports jet dragster accident in 2011, where a dragster hit the wall at 270 mph between a 43 to 60 degree angle. A static structural simulation, using the dragster chassis, was modeled in ANSYS and several dynamic simulations at varying impact angles were …

Markerless Kinematics Of Pediatric Manual Wheelchair Mobility, Jacob Robert Rammer

Dissertations (1934 -)

Pediatric manual wheelchair users face substantial risk of orthopaedic injury to the upper extremities, particularly the shoulders, during transition to wheelchair use and during growth and development. Propulsion strategy can influence mobility efficiency, activity participation, and quality of life. The current forefront of wheelchair biomechanics research includes translating findings from adult to pediatric populations, improving the quality and efficiency of care under constrained clinical funding, and understanding injury mechanisms and risk factors. Typically, clinicians evaluate wheelchair mobility using marker-based motion capture and instrumentation systems that are precise and accurate but also time-consuming, inconvenient, and expensive for repeated assessments. There is …

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 …

Bs News July/August

Building Services Engineering

No abstract provided.

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 …

Nanosecond Electric Pulses Differentially Affect Inward And Outward Currents In Patch Clamped Adrenal Chromaffin Cells, Lisha Yang, Gale L. Craviso, P. Thomas Vernier, Indira Chatterjee, Normand Leblanc

Bioelectrics Publications

This study examined the effect of 5 ns electric pulses on macroscopic ionic currents in whole-cell voltage-clamped adrenal chromaffin cells. Current-voltage (I-V) relationships first established that the early peak inward current was primarily composed of a fast voltage-dependent Na⁺ current (I_Na), whereas the late outward current was composed of at least three ionic currents: a voltage-gated Ca²⁺ current (I_Ca), a Ca²⁺-activated K⁺ current (I_K(Ca)), and a sustained voltage-dependent delayed rectifier K⁺ current (I_KV). A constant-voltage step protocol was next used to monitor peak inward and late …

Microwave Interferometry Diagnostic Applications For Measurements Of Explosives, Loren A. Kline

Master's Theses

Microwave interferometry (MI) is a Doppler based diagnostic tool used to measure the detonation velocity of explosives, which has applications to explosive safety. The geometry used in existing MI experiments is cylindrical explosives pellets layered in a cylindrical case. It is of interest to Lawrence Livermore National Labs to measure additional geometries that may be overmoded, meaning that the geometries propagate higher-order transverse electromagnetic waves. The goal of my project is to measure and analyze the input reflection from a novel structure and to find a good frequency to use in an experiment using this structure. Two methods of determining …

Elastic Properties Of Superconductors And Materials With Weakly Correlated Spins, Christian Binek

Christian Binek Publications

It is shown that in the ergodic regime, the temperature dependence of Young’s modulus is solely determined by the magnetic properties of a material. For the large class of materials with paramagnetic or diamagnetic response, simple functional forms of the temperature derivative of Young’s modulus are derived and compared with experimental data and empirical results. Superconducting materials in the Meissner phase are ideal diamagnets. As such, they display remarkable elastic properties. Constant diamagnetic susceptibility gives rise to a temperature independent elastic modulus for ceramic and single crystalline superconductors alike. The thermodynamic approach established in this report, paves the way to …

Viscoelastic Effects In Carbon Fiber Reinforced Polymer Strain Energy Deployable Composite Tape Springs, Elisa C. Borowski

Civil Engineering ETDs

Strain energy deployable composite structures are of great importance to the aerospace community due to their light weight, high stiffness, impressive flexibility, compact stowage configuration, and ability to self-deploy. These attributes make composite deployable hinges ideal for aerospace applications that can benefit from decreased payload and decreased structural complexity through a reduction in deployment parts. However, successful application of these deployable structures requires an in-depth understanding of their mechanical behavior throughout stowage and deployment processes. Upon release from a high strain stowage configuration, high deployment accelerations caused by a great amount of stored strain energy could potentially damage the structure …

Time Varying Parameter Models For Catchments With Land Use Change: The Importance Of Model Structure, Sahani Pathiraja, Daniela Anghileri, Paolo Burlando, Ashish Sharma, Lucy Marshall, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Rapid population and economic growth in South-East-Asia has been accompanied by extensive land use change with consequent impacts on catchment hydrology. Modelling methodologies capable of handling changing land use conditions are therefore becoming ever more important, and are receiving increasing attention from hydrologists. A recently developed Data Assimilation based framework that allows model parameters to vary through time in response to signals of change in observations is considered for a medium sized catchment (2880 km²) in Northern Vietnam experiencing substantial but gradual land cover change. We investigate the efficacy of the method as well as the importance of the chosen …

Considering Health In Us Metropolitan Long-Range Transportation Plans: A Review Of Guidance Statements And Performance Measures, Patrick A. Singleton, Kelly J. Clifton

Civil and Environmental Engineering Faculty Publications and Presentations

Transportation influences health primarily and most directly through traffic safety, air quality, physical activity, and accessibility. Despite the importance of all four components, only safety and air quality are typically considered during institutionalized transportation planning processes. This paper assesses how health impacts are considered in transportation planning by focusing on the long-range transportation plans that US metropolitan planning organizations develop. We analyzed the content of current plans from 25 large regions, reviewing how policy guidance statements and supporting performance measures addressed health. Goals and objectives exhibited an incomplete perspective of transportation's effects on health, focusing on safety, accessibility, and air …

A Simulator-Based Analysis Of Engineering Treatments For Right-Hook Bicycle Crashes At Signalized Intersections, Jennifer Warner, David S. Hurwitz, Christopher M. Monsere, Kayla Fleskes

Civil and Environmental Engineering Faculty Publications and Presentations

A right-hook crash is a crash between a right-turning motor vehicle and an adjacent through-moving bicycle. At signalized intersections, these crashes can occur during any portion of the green interval when conflicting bicycles and vehicles are moving concurrently. The objective of this research was to evaluate the effectiveness of four types of engineering countermeasures – regulatory signage, intersection pavement marking, smaller curb radius, and protected intersection design – at modifying driver behaviors that are known contributing factors in these crashes. This research focused on right-hook crashes that occur during the latter stage of the circular green indication at signalized intersections …

High Precision Refractive Index Measurement Techniques Applied To The Analysis Of Neutron Damage And Effects In Caf2 Crystals, Joseph P. Morris Ph.D.

Nuclear Engineering ETDs

Neutron irradiation damages material by atomic displacements. The majority of these damage regions are microscopic and difficult to study, though they can cause a change in density and thus a change in refractive index in transparent materials. This work utilized CaF₂ crystals to track refractive index change based on neutron radiation dose. High precision refractive index measurements were performed utilizing a nested-cavity mode-locked laser where the CaF₂ crystal acted as a Fabry-Pérot Etalon (FPE). By comparing the repetition rate of the cavity and the repetition rate of the FPE, refractive index change was determined. Following several irradiation experiments, …

Gms: Grid-Based Motion Statistics For Fast, Ultra-Robust Feature Correspondence, Jiawang Bian, Wen-Yan Lin, Matsushita Yasuyuki, Sai-Kit Yeung, Tan-Dat Nguyen, Ming-Ming Cheng

Research Collection School Of Computing and Information Systems

Incorporating smoothness constraints into feature matching is known to enable ultra-robust matching. However, such formulations are both complex and slow, making them unsuitable for video applications. This paper proposes GMS (Grid-based Motion Statistics), a simple means of encapsulating motion smoothness as the statistical likelihood of a certain number of matches in a region. GMS enables translation of high match numbers into high match quality. This provides a real-time, ultra-robust correspondence system. Evaluation on videos, with low textures, blurs and wide-baselines show GMS consistently out-performs other real-time matchers and can achieve parity with more sophisticated, much slower techniques.

Cyber Foraging: Fifteen Years Later, Rajesh Krishna Balan, Jason Flinn

Research Collection School Of Computing and Information Systems

Revisiting Mahadev Satyanarayanan's original vision of cyber foraging and reflecting on the last 15 years of related research, the authors discuss the major accomplishments achieved as well as remaining challenges. They also look to current and future applications that could provide compelling application scenarios for making cyber foraging a widely deployed technology. This article is part of a special issue on pervasive computing revisited.

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

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

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

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. …