Engineering Commons^™

Planar Linear Ion Traps With Microscale Radii For Portable Mass Spectrometry, Trevor Keith Decker

Theses and Dissertations

Radio frequency (RF) ion traps based on the quadrupole device developed by Paul and Steinwedel utilize a dynamic electric field to spatially confine the trajectory of charged particles and may be employed as mass spectrometers by selectively ejecting trapped molecules based on the mass to charge ratio. Because of the inherent sensitivity and specificity of this process, ion trap mass spectrometers have become a popular scientific instrument. In the past two decades there has been a push to develop portable ion trap mass spectrometers for in situ mass analysis by geometrically scaling traps to smaller sizes. This decreases the power …

5d Grain Boundary Characterization From Ebsd Microscopy, Akash Savio Amalaraj

Theses and Dissertations

Knowledge of the full 5-degree Grain Boundary Character Distribution (GBCD) is vital to understanding properties, such as gas diffusivity, that are dominated by grain boundary character. Surface characterization techniques, such as Electron Backscattered diffraction (EBSD), can provide only 4 of the 5 GB characteristics (the rotation between the neighboring grains, and the trace of the GB on the surface). The inclination of the GB in the direction normal to the surface is not known. A previous study indicated that the GB inclination could be recovered by correlating the Electron Backscattered patterns (EBSPs) of sample points near the GB with EBSPs …

Synthesis And Design Of Metals Sulfide/Carbon Composite-Fibers Anodes For Lithium Ion Batteries, Jorge Lopez

Theses and Dissertations

In this study, Forcespinning is used to produce Titanium sulfide (TiS2)/carbon composite fibers for use as lithium-ion battery anodes. The high surface area to volume ratio of the composite fibers can have a high impact on the ionic and electronic conductivity of the active materials leading to improved electrochemical performance of the battery. TiS2 nanoparticles were chosen as the active materials to produce Metal-Li-alloys/C composite fibers due to their high theoretical capacity and low volume change during charge/discharge cycles. The use of a 2-D layered structure of TiS2 nanoparticles in the carbon fiber matrix can greatly accommodate more Li-ions between …

Assuring Intellectual Property Through Physical And Functional Comparisons, Adam Kendall Hastings

Theses and Dissertations

Hardware trojans pose a serious threat to trusted computing. However, hardware trojan detection methods are both numerous and onerous, making hardware trojan detection a difficult and time-consuming procedure. This thesis introduces the IP Assurance Framework, which drastically improves the time it takes design teams to test for hardware trojans. The IP Assurance Framework is implemented in two ways: The first method, Physical Assurance, compares instantiated IP blocks to a golden model via physical-level comparisons, while the second method, Functional Assurance, compares IP to a golden model using logical-level comparisons. Both methods are demonstrated to distinguish between tampered and untampered IP …

Analysis Of The Effects Of Inlet Distortion On Stall Cell Formation In A Transonic Compressor Using Create-Av Kestrel, Mikkel Andreas Unrau

Theses and Dissertations

Accurately predicting fan performance, including bounds of operation, is an important function of any Computational Fluid Dynamics (CFD) package. The presented research uses a CFD code developed as part of the Computational Research and Engineering Acquisition Tools and Environment (CREATE), known as Kestrel, to evaluate a single stage compressor at various operating conditions. Steady-state, single-passage simulations are carried out to validate capabilities recently added to Kestrel. The analysis includes generating speedlines of total pressure ratio and efficiency, as well as radial total temperature and total pressure profiles at two axial locations in the compressor at various operating conditions and fan …

Swat Online: Development Of A Web-Based Decision Support System For The Soil And Water Assessment Tool, Spencer Dean Mcdonald

Theses and Dissertations

As satellite and climate modelling technology continues to improve and as climatological disasters and issues continue to impact the global community, climate data will increase in size and relevance. With this new influx of information, it is becoming more and more important for scientists to simply and concisely communicate their findings to both decision makers in governments and disaster preparedness organizations and also to the general public. The Soil and Water Assessment Tool (SWAT) is a powerful modelling tool that allows scientists to simulate essentially all of the physical processes involved in the water cycle. The data that SWAT produces …

Investigation Of An Isotruss Structure As A Compliant Member Used In Bending And Torsion, Jens Garret Jacobson

Theses and Dissertations

An investigation of IsoTruss structures in bending and torsion was conducted. A model was developed in ANSYS APDL where bay length and longitudinal member to helical member cross-sectional area ratio could be varied while holding the diameter constant. The model was validated using previously reported values from analytical models and empirical data. The model was used to make predictions of a specific geometry that was manufactured, tested and compared against the model. 12 specimens were built and tested. In flexure, empirical data had a percent error with respect to the model ranging from 10.9 to 65.4% with one outlier at …

Estimation Of Knee Kinematics Using Non-Monotonic Nanocomposite High-Deflection Strain Gauges, Adin Douglas Martineau

Theses and Dissertations

Human knee kinematics, especially during gait, are an important analysis tool. The current "gold standard" for kinematics measurement is a multi-camera, marker-based motion capture system with 3D position tracking. These systems are accurate but expensive and their use is limited to a confined laboratory environment. High deflection strain gauges (HDSG) are a novel class of sensors that have the potential to measure kinematics and can be inexpensive, low profile, and are not limited to measurements within a calibrated volume. However, many HDSG sensors can have a non-linear and non-monotonic response. This thesis explores using a nanocomposite HDSG sensor system for …

Rapid Separation Of Bacteria From Blood For Sepsis Diagnosis, Mahsa Alizadeh

Theses and Dissertations

Sepsis is a severe blood infection caused by bacteria entering the blood stream. Sepsis caused by antibiotic resistant bacteria is very dangerous with a high mortality rate. The current clinical diagnostic methods for sepsis require culturing the blood sample prior to other steps of the diagnosis procedure. Culturing the blood samples is a time-consuming step which increases the time required for the diagnostic procedure. Considering the fact that the mortality rate of the sepsis increases as time passes, it is essential to find methods for sepsis diagnosis that do not require culturing the samples. The first step of a new …

Development Of A Simplified Analysis Approach For Predicting Pile Deflections Of Piers Subjected To Lateral Spread Displacements And Application To A Pier Damaged During The 2010 Maule, Chile, M8.8 Earthquake, Logan Matthew Palmer

Theses and Dissertations

The 2010, moment magnitude 8.8 earthquake that occurred near Maule, Chile caused major damages to several piers in the Port of Coronel located approximately 160 kilometers (100 miles) to the South of the earthquake epicenter. One of the piers, the North Pier, experienced significant lateral spreading that was caused from liquefaction of the soils at the approach zone of the pier. Damages from lateral spreading and liquefaction effects consisted of sheet pile welding ruptures of the cross-support beams, stiffener buckling, pile displacements, pile rotations, and pier deck displacement. Researchers analyzed the North Pier after the earthquake and documented in detail …

Optimization-Based Spatial Positioning And Energy Management For Unmanned Aerial Vehicles, Ronald Abraham Martin

Theses and Dissertations

This research applies techniques from the field of optimization to spatial positioning and energy management in Unmanned Aerial Vehicles (UAVs). Two specific areas are treated: optimization of UAV view plans for 3D modeling of infrastructure, and trajectory optimization of solar powered high-altitude long-endurance (HALE) UAVs. Structure-from-Motion (SfM) is a computer vision technique for creating 3D models from 2D images. View planning is the process of planning image sets that will effectively model a given scene. First, a genetic algorithm based view planning approach is demonstrated. A novel terrain simulation environment is developed, and the algorithm is tested at multiple sites …

Large-Scale Non-Linear Dynamic Optimization For Combining Applications Of Optimal Scheduling And Control, Logan Daniel Beal

Theses and Dissertations

Optimization has enabled automated applications in chemical manufacturing such as advanced control and scheduling. These applications have demonstrated enormous benefit over the last few decades and continue to be researched and refined. However, these applications have been developed separately with uncoordinated objectives. This dissertation investigates the unification of scheduling and control optimization schemes. The current practice is compared to early-concept, light integrations, and deeper integrations. This quantitative comparison of economic impacts encourages further investigation and tighter integration. A novel approach combines scheduling and control into a single application that can be used online. This approach implements the discrete-time paradigm from …

Pore Pressure Generation And Shear Modulus Degradation During Laminar Shear Box Testing With Prefabricated Vertical Drains, Landon Scott Kinney

Theses and Dissertations

Liquefaction is a costly phenomenon where soil shear modulus degrades as the generation of excess pore pressures begins. One of the methods to mitigate liquefaction, is the use of prefabricated vertical drains. Prefabricated vertical drains provide a drainage path to effectively mitigate the generation of pore pressures and aid in shear modulus recovery. The aims of this study were to define shear modulus degradation vs. shear strain as a function of excess pore pressure ratio; define the effects of prefabricated vertical drains on the behavior of pore pressure generation vs. shear strain; and to define volumetric strain as a function …

Two-Phase Interactions On Superhydrophobic Surfaces, Kimberly Ann Stevens

Theses and Dissertations

Superhydrophobic surfaces have gained attention as a potential mechanism for increasing condensation heat transfer rates. Various aspects related to condensation heat transfer are explored. Adiabatic, air-water mixtures are used to explore the influence of hydrophobicity on two-phase flows and the hydrodynamics which might be present in flow condensation environments. Pressure drop measurements in a rectangular channel with one superhydrophobic wall (cross-section approximately 0.37 X 10 mm) are obtained, revealing a reduction in the pressure drop for two-phase flow compared to a control scenario. The observed reduction is approximately 10% greater than the reduction that is observed for single-phase flow (relative …

Property Localization For Grain Boundary Diffusivity Via Inverse Problem Theory, Christian Kurniawan

Theses and Dissertations

The structure and spatial arrangement of grain boundaries strongly affect the properties of polycrystalline materials such as corrosion, creep, weldability, superconductivity, and diffusivity. However, constructing predictive grain boundary structure-property models is taxing, both experimentally and computationally due to the high dimensionality of the grain boundary character space. The purpose of this work is to develop an effective method to infer grain boundary structure-property models from measurement of the effective properties of polycrystals by utilizing the inverse problem theory. This study presents an idealized case in which structure-property models for grain boundary diffusivity are inferred from a noisy simulation. The method …

Strength Investigation Of Damaged And Repaired Thin-Walled Composite Structures, Analise Barlow

Theses and Dissertations

The purpose of this research was to quantify the strength of novel composite repair methods for thin-walled composite structures. Carbon/epoxy plates were manufactured and repairs were made at Gloyer-Taylor Laboratories. At BYU, specimens were damaged in a controlled and repeatable process. Three damage modes were implemented: impact, groove, and abrasive damage. Tensile strength tests were performed on control, damaged, and repaired specimens. Four 24 x 24 in (60 x 60 cm) carbon/epoxy plates were received. Each plate was made up of seven plies cured together with epoxy resin for a nominal total thickness of 0.04 in (1.02 mm). The thickness, …

Quantitative Measurement Techniques For Vibration And Buffet, Edward Thomas Meyer

Theses and Dissertations

This paper outlines a proposed parameter for measurement of vibration and buffet in vehicles. It is intended to be used where applicable in lieu of raw accelerometer data or qualitative comments to measure ride quality, quantify vibration levels, and aid in certification matters. In flight vehicle applications which employ fly-by wire flight control systems with closed loop and variable gain control laws, the phenomenon of buffet in its various forms is becoming somewhat specious as an aircrew cue in relation to the stability and control of flight vehicles. In these applications, stability and control throughout the operating envelope is designed …

Development Of Adaptable Human-Machine Interface For Teleoperation Over Time Delay, May Nyein Chan

Theses and Dissertations

The Adaptable Human-Machine Interface (AHMI) was developed for the Orbital Robotic Interaction, On-orbit servicing, and Navigation (ORION) Laboratory of the Florida Institute of Technology. The primary project objective was to develop and test a predictive display for mitigating the effects of time delay in teleoperation of space robots and Unmanned Aerial Vehicles (UAV) using quadcopters as a test case. Regardless of the increasing popularity of various autonomous systems, research and development of teleoperating system should not be neglected since it is often utilized as a back-up in most autonomous systems especially in systems for human spaceflight and UAV operations in …

Cloud Based Wireless Sensor Monitoring, Pruthvi Devendrakumar Mistry

Theses and Dissertations

Internet of Things (IoT) brought a revolutionary change in embedded systems. It offloads the physical work of managing an equipment, appliance or device to a smart and network connected application. IoT makes it possible to monitor and control a huge network of devices remotely. The aim of this project is to develop a complete framework for smart data acquisition from a wireless sensor network to cloud servers. The framework includes configurable, low power, and small size embedded module that is attached to a sensor. The device reads data from the sensor and forwards them to the cloud server using the …

Mindful: A Novel Virtual System Migration Decision-Making Framework For Automated Cyber-Resiliency, Nicholas James Lowing

Theses and Dissertations

Virtual system migration has revolutionized modern computing. As an advantageous byproduct of virtualization, virtual system migration has allowed for cheaper, more robust cloud management. The selection of a destination host during migration is a key component of migration management. However, there is currently no state-of-the-art, standardized framework for making this decision. Previous work related to automated load balancing is plentiful, but when load balancing is not the primary focus of the cloud management strategy there is a lack of research. We focus on this case, where virtual systems are no longer moved based on some predefined optimization pattern, but rather …

Human-Centered Design Of The Enhanced Pilot Learning Interface For The Aviation Community, De Vere Michael Kiss

Theses and Dissertations

he purpose of this research is to introduce a new device to help pilots navigate aircraft manuals. This informational navigational tool is designed to improve learning by reducing the time it takes a pilot candidate to retrieve aircraft system information within an aircraft manual. The device is called the Enhanced Pilot Learning Interface, an Advanced Interactive Media. The research project is based on human-centered design and consists of participatory design, modeling and simulation, human-in-the-loop simulation (HITLS), and expert user experience. Additionally, a traditional research experimentation was conducted to collect supporting statistical data. Preliminary tests of four current professional airline pilots …

Evaluation Of Bond Properties Between Fiber Reinforced Concrete Overlay And Substrate Concrete, Emad Okrush Alshammari

Theses and Dissertations

Bonded concrete overlay is the most economical and quick option in concrete rehabilitation methods to provide strength for the existing structure. Bonded concrete overlay strength rely on properties of both layers (substrate and new layers). Poor bonding in interface zone leads to two main failures of concrete overlays; debonding and cracks. There are several traditional factors affect bond strength such as water to cement (w/c) ratio, moisture condition, and surface roughness for substrate layer. However, the effect of using fiber consider a new variable affecting bond strength. Fiber reinforced concrete (FRC) is one type of overlay system which has been …

Computational Support For Predicting Requirement Change Volatility In Complex System Design, Phyo Htet Hein

Theses and Dissertations

Requirements play critical role in the design process as objective statements of stakeholders’ expectations. Design process is iterative, and requirements are also constantly changed and updated to reflect stakeholders’ expectations, design changes, regulations, resource limitations, etc. Managing requirement change is one of the most important requirement management tasks. Since requirements are driving factors in product development from initial concept development stage to final production, mismanaged requirement changes can adversely affect project health leading to monetary and time losses. The ability to assess a requirement change and predict its propagation early in the design process will enable engineers to make informed …

Exploratory Analysis Of Accuracy Monitoring Techniques In Vehicle Detection Systems For Intelligent Transportation Systems Applications And Maintenance, Manasi Sanjay Palod

Theses and Dissertations

The goal of transportation management is to ensure the mobility of people and goods, in a reliable and efficient manner. Operation and maintenance of transportation infrastructure is key to accomplish their objectives. Intelligent Transportation Systems (ITS) applications rely on massive detection networks that collectively demand significant maintenance resources. Resource constraints force transportation agencies to look for innovative ways to optimize their operational and maintenance costs while serving their users at intended performance levels. The system inputs come from vehicle detection system (VDS), acting as field data collection devices, enabling traffic monitoring and management through response to specific conditions. This research …

Distributed Electric Propulsion Conceptual Design Applied To Traditional Aircraft Take Off Distance Through Multidisciplinary Design, Kevin Ray Moore

Theses and Dissertations

While vertical takeoff and landing aircraft show promise for urban air transport, distributed electric propulsion on existing aircraft may offer an immediately implementable alternative. Dis- tributed electric propulsion has the potential of increasing the aircraft thrust-to-weight ratio and lift coefficient high enough to enable takeoff distances of less than 100 meters. While fuel based propulsion technologies generally increase in specific power with increasing size, electric propul- sion typically can be decreased in size without a decrease in specific power. The smaller but highly power-dense propulsion units enable alternative designs including many small units, optionally powered units, and vectored thrust from …

Big Data And Sensor Network For Construction Material Testing, Yao Shi

Theses and Dissertations

Engineers and contractors need to have a precise understanding of the development progress of concrete strength in the natural environment, which helps to save project time and cost. However, current practice of concrete construction depends on published data, charts and curves from laboratory tests. The data would not show frequently changing environmental conditions in the real world, which can affect concrete quality significantly. The objective of this research is to design a reliable and accurate method to validate test data of the strength developments of concrete specimens in early stages. The approach includes the following tasks: (1) arrange sensors to …

An Investigation Of Conformality Of The Core-Shell Polymer Electrolyte Membrane (Pem) Fuel Cell Catalysts By Sputter Deposition, Mesut Yurukcu

Theses and Dissertations

Core-shell nanorod array geometry can offer enhanced durability for polymer electrolyte membrane (PEM) fuel cell electrodes if a catalyst shell is conformally coated around the nanorod support base. Uniform catalyst shell coating can minimize the interaction of acidic fuel cell medium with the nanorod base and can improve the overall electrocatalyst electrode stability. However, fabrication of the conformal shell layers on nanorod arrays using physical vapor deposition (PVD) methods (e.g. sputtering, thermal evaporation) has been a formidable task. In order to assess the PVD conditions for the production of conformal shell coatings, Monte Carlo simulation methods (MC) can provide useful …

Characterizing Interfacial Bonds In Hybrid Metal Am Structures, John Ross Linn

Theses and Dissertations

The capabilities of various metal Additive Manufacturing (AM) processes, such as Powder Bed Fusion – Laser (PBF-L) and Direct Energy Deposition (DED) are increasing such that it is becoming ever more common to use them in industrial applications. The ability to print atop a substrate broadens that scope of applications. There is ongoing research regarding the mechanical properties of additively processed materials, but little regarding the interaction between additive material and its substrate. An understanding of the mechanical and performance properties of the AM/substrate interface is imperative. This paper describes a study of the strength properties of AM/substrate interfaces, with …

Gjendja Kufitare E Shfrytëzimit Sipas Ec-2 Plasaritjet Dhe Deformimet, Përparim Neziri

Theses and Dissertations

Në shumë situata të projektimit performanca e pranueshme e strukturave përcaktohet nga kërkesat e shfrytëzueshmërisë. Projektimi sipas shfrytëzueshmërisë në disa aspekte është më i vështirë për t’u kuptuar gjatë projektimit të strukturave të betonit. Kërkesat më të zakonshme që duhet të plotësohen për projektimin sipas Gjendjes Kufitare te Shfrytëzimit janë kufizimi i përkuljes dhe gjerësisë së plasaritjeve sipas kërkesave të kodit në fuqi. Ky material ofron një diskutim të sjelljes strukturore në ngarkesat e shfrytëzueshmërisë dhe metodat e thjeshtuara për kontrollin e perkuljes dhe plasaritjeve që perfshihen në disa nga kodet kryesore të praktikës janë paraqitur, përfshirë Eurokodi 2. Përkulja …

Projektimi Dhe Llogaritja E Konstruksioneve Të Kulmit, Linda Fejzulahi

Theses and Dissertations

Nga koncepti i diplomës lidhur me projektimin dhe llogaritjejn e konstruksionit të kulmit, të projektuar dhe llogaritur janë realizuar këto faza:

Analizat e ngarkesave, ngarkesat e përhershme, ngarkesat e përkohshme, ngarkesat llogaritëse, ngarkesat nga bora, ngarkesat nga era, ndikimet e brendshme, kombinimi ngarkesave, etj.

Projektimi është paraparë të bëhen në periferi të Bujanocit, afer liqenit artficial. Janë projektuar 6 shtëpi malore, tri prej të cilave jane vetëm përdhesë, dhe tri të tjera P+1.