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The Creation, Validation, And Implementation Of The Engineering Process Safety Research Instrument, Brittany Lynn Butler Dec 2018

The Creation, Validation, And Implementation Of The Engineering Process Safety Research Instrument, Brittany Lynn Butler

Theses and Dissertations

The purpose of this study was to develop and validate an instrument that can measure how senior chemical engineering students make process safety decisions. The Engineering Process Safety Research Instrument (EPSRI) contains dilemmas that represent process safety scenarios, followed by three decision options, and 12-15 considerations that fall into pre-conventional, conventional, or post-conventional forms of reasoning. Three studies were completed as a part of this research. The content validation study ensured the dilemmas represented process safety scenarios, the considerations matched their perceived theoretical definitions, and that no content areas were omitted. This study resulted in validation of the content, following …


A Microscopic Simulation Laboratory For Evaluation Of Off-Street Parking Systems, Yun Yuan Dec 2018

A Microscopic Simulation Laboratory For Evaluation Of Off-Street Parking Systems, Yun Yuan

Theses and Dissertations

The parking industry produces an enormous amount of data every day that, properly analyzed, will change the way the industry operates. The collected data form patterns that, in most cases, would allow parking operators and property owners to better understand how to maximize revenue and decrease operating expenses and support the decisions such as how to set specific parking policies (e.g. electrical charging only parking space) to achieve the sustainable and eco-friendly parking.

However, there lacks an intelligent tool to assess the layout design and operational performance of parking lots to reduce the externalities and increase the revenue. To address …


Applications Of Dynamic Mode Decomposition And Sparse Reconstruction In The Data-Driven Dynamic Analysis Of Physical Systems, Mojtaba F. Fathi Dec 2018

Applications Of Dynamic Mode Decomposition And Sparse Reconstruction In The Data-Driven Dynamic Analysis Of Physical Systems, Mojtaba F. Fathi

Theses and Dissertations

Recent advancements in data collection methods and equipment have resulted in a huge increase in the amount of data collected by observing various types of physical phenomena. Regardless of the amount of data collected, it is well known for many physical systems, the so-called information rank of the collected data is much lower than the rank of the data itself. This usually means the data may be represented sparsely in terms of a properly-chosen basis. This realization has led to methods for storing large amounts of data through compression by sacrificing negligible data quality. More importantly, with the advent of …


Fabrication Of Silver-Doped Zinc Oxide Thin Films Through Optimized Sol-Gel Deposition And Nanoparticle Wetting Process, Reed T. Heintzkill Dec 2018

Fabrication Of Silver-Doped Zinc Oxide Thin Films Through Optimized Sol-Gel Deposition And Nanoparticle Wetting Process, Reed T. Heintzkill

Theses and Dissertations

Zinc Oxide (ZnO) has been of significant interest as a Transparent Conductive Oxide (TCO) given its sizable direct band-gap, and as a potential substitute for Indium-Tin Oxide for use in opto-electronic and piezo-electric devices, due to its comparatively abundant and nontoxic precursor materials. Sol-gel processing is an easy, low-energy method for fabricating ZnO thin films, and there has been increasing interest in doping the compound such to give it p-type semiconductive character.

This thesis thoroughly investigates sol-gel processing of ZnO thin solid films, with focus on wet-chemistry (sol-gel) methods of doping the material with silver (both as elemental ions and …


Transient Analysis Of A Coolant-To-Refrigerant Heat Exchanger To Provide Temporary High Performance In An Automotive Vehicle, Abhinav Ravi Dec 2018

Transient Analysis Of A Coolant-To-Refrigerant Heat Exchanger To Provide Temporary High Performance In An Automotive Vehicle, Abhinav Ravi

Theses and Dissertations

The objective of this thesis is to provide a numerical and experimental design tool to understand the heat transfer analysis of a coolant reservoir being chilled at a sub-ambient temperature with a goal of eventually providing a transient burst in performance. A high performance vehicle usually has a liquid charge air cooler that cools air before entering the engine. This liquid charge air cooler cools the air by using a specific coolant coming from the low temperature radiator. This study involves a coolant reservoir independent of the low-temperature radiator to provide coolant at a sub-ambient temperature to the liquid charge …


Probabilistic Reliability Analysis Of The Water-Energy Nexus Using Monte Carlo Simulation, Yunfan Zhang Dec 2018

Probabilistic Reliability Analysis Of The Water-Energy Nexus Using Monte Carlo Simulation, Yunfan Zhang

Theses and Dissertations

Nowadays, with the development of science and technologies, our modern society is more and more dependent on the reliable performance of the critical infrastructures. Both water systems and power systems are national critical infrastructure supporting our daily life and the development of economic growth. These two types of systems are highly interconnected and complex networks, which consist of various system elements. Similarly, the core function of water and power system is to deliver satisfactory quality water and power to consumers, and at the same time it should satisfy all the demands at all load points. The reliable performance of these …


Characterization Of Pyrolysis Products From Fast Pyrolysis Of Live And Dead Vegetation, Mohammad Saeed Safdari Dec 2018

Characterization Of Pyrolysis Products From Fast Pyrolysis Of Live And Dead Vegetation, Mohammad Saeed Safdari

Theses and Dissertations

Wildland fire, which includes both planned (prescribed fire) and unplanned (wildfire) fires, is an important component of many ecosystems. Prescribed burning (controlled burning) is used as an effective tool in managing a variety of ecosystems in the United States to reduce accumulation of hazardous fuels, manage wildlife habitats, mimic natural fire occurrence, manage traditional native foods, and provide other ecological and societal benefits. During wildland fires, both live and dead (biomass) plants undergo a two-step thermal degradation process (pyrolysis and combustion) when exposed to high temperatures. Pyrolysis is the thermal decomposition of organic material, which does not require the presence …


Assuring Intellectual Property Through Physical And Functional Comparisons, Adam Kendall Hastings Dec 2018

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 …


Examining The Mechanics Responsible For Strain Delocalization In Metallic Glass Matrix Composites, Casey Owen Messick Dec 2018

Examining The Mechanics Responsible For Strain Delocalization In Metallic Glass Matrix Composites, Casey Owen Messick

Theses and Dissertations

Metallic glass matrix composites (MGMCs) have been developed to improve upon the ductility of monolithic metallic glass. These composites utilize a secondary crystalline phase that is grown into an amorphous matrix as isolated dendritic trees. This work seeks to understand the mechanisms underlying strain delocalization in MGMCs in order to better direct efforts for continual progress in this class of material. A mesoscale modelling technique based on shear transformation zone (STZ) dynamics is used to do so. STZ dynamics is a coarse grained technique that can provide insight into the microscopic processes that control macroscopic behavior, but which can be …


Equivalent Circuit Model Generation For Batteries Using Non-Ideal Test Data, Logan Crain Dec 2018

Equivalent Circuit Model Generation For Batteries Using Non-Ideal Test Data, Logan Crain

Theses and Dissertations

Modeling is a key component in the development of battery products. While there are multiple levels of complexity which may be achieved in model development, equivalent circuit modeling is able to quickly produce reliable and accurate predictions for battery behavior. While the use of equivalent circuit models has been described in great detail for lithium ion batteries, it is also desirable to use this methodology regardless of chemistry, specifically with respect to lead-acid technology. When developing battery models for predicting battery behavior in a vehicle, the testing methods meant to mimic vehicle applications often cause non-ideal data for model generation. …


Coordination And Control For A Team Of Mobile Robots In An Unknown Dynamic Environment, Sucheta Roy Dec 2018

Coordination And Control For A Team Of Mobile Robots In An Unknown Dynamic Environment, Sucheta Roy

Theses and Dissertations

This research presents a dual-level control structure for controlling a mobile robot or a group of robots to navigate through a dynamic environment (such as an object is moving in the workspace of a robot). The higher-level controller operates in cooperation with robot’s state estimation and mapping algorithm, Extended Kalman Filter – Simultaneous Localization and Mapping (EKFSLAM), and the lower-level controller (PID) controls the motion of the robot when it, encounters an obstacle, i.e., it reorients the robot to a predefined rebound angle and move it straight to maneuver around the obstacle until the robot is out of the obstacle …


Evaluation And Influence Of Recycled Concrete Aggregate Base Layers On Hma Pavement Performance, Jessie Daniel Ramirez Dec 2018

Evaluation And Influence Of Recycled Concrete Aggregate Base Layers On Hma Pavement Performance, Jessie Daniel Ramirez

Theses and Dissertations

This research investigated the influence of the RCA base layers on the HMA pavement performance as compared with CA base layers using laboratory tests on collected base layer materials and field tests on corresponding pavement sections. Field and laboratory testing programs were conducted to investigate RCA and CA base layer materials in which identified test sections at the selected pavement sites were subjected to testing using FWD, walking profiler, and DCP. Visual distress surveys were also conducted at the selected pavement sections. RCA and CA base layer samples were collected from these pavement sites and were subjected to a laboratory …


Repopulation And Stimulation Of Porcine Cardiac Extracellular Matrix To Create Engineered Heart Patches, Silvia Juliana Moncada Diaz Dec 2018

Repopulation And Stimulation Of Porcine Cardiac Extracellular Matrix To Create Engineered Heart Patches, Silvia Juliana Moncada Diaz

Theses and Dissertations

Heart failure is the main cause of death for both men and women in the United States. The only proven treatment for patients with heart failure is heart transplantation. The goal of this research is to create patches of tissue that could mimic the function of the native heart to repair the damaged portions of the heart. In this study, whole porcine hearts were decellularized to create a 3D construct that was recellularized with cardiomyocytes (CM) differentiated from human induced pluripotent stem (IPS) cells. At day 4 of differentiation, IPS-derived CMs were implanted onto cardiac extracellular matrix (cECM) and ten …


Swat Online: Development Of A Web-Based Decision Support System For The Soil And Water Assessment Tool, Spencer Dean Mcdonald Dec 2018

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 …


Relationship Between Compressive Strength Of Different Shape And Thickness Specimens Of Type S Mortar, Theodore James Moffett Dec 2018

Relationship Between Compressive Strength Of Different Shape And Thickness Specimens Of Type S Mortar, Theodore James Moffett

Theses and Dissertations

Mortar is the cementitious binding material placed between masonry blocks to create a composite system. The American Society of Testing and Materials (ASTM), along with other organizations, have established the testing of prismatic mortar specimens for evaluating mechanical properties, like compressive strength. Mortar joints, however, possess vastly different characteristics compared to prismatic specimens, especially in terms of geometry and water content. These differences prevent a direct comparison of compressive strength between prismatic specimens and actual mortar joints in the assembly. The objective of this study was to analyze Type S mortar joints, with particular emphasis on specimen shape and water …


Experimental Evaluation Of Replaceable Shear Fuse Moment Connections, Shannon Shun Oh Dec 2018

Experimental Evaluation Of Replaceable Shear Fuse Moment Connections, Shannon Shun Oh

Theses and Dissertations

Steel special moment frames (SMFs) are known to be highly ductile seismic force- resisting systems. The performance of an SMF relies on the ability of the connections to accommodate large inelastic deformations. After the brittle failure of some steel moment frame connections during the 1994 Northridge Earthquake, experimental tests were used to investigate the ductility and strength of these connections. An experimental study was performed to investigate the seismic performance a new connection called the Replaceable Shear Fuse (RSF) connection. The RSF connection uses shear-yielding fuse plates to prevent beam and column yielding. A total of 7 test specimens with …


Planar Linear Ion Traps With Microscale Radii For Portable Mass Spectrometry, Trevor Keith Decker Dec 2018

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 …


An Analytical Model Of Material Deformation In Rotary Friction Welding Of Thin-Walled Tubes, Caleb James Brown Dec 2018

An Analytical Model Of Material Deformation In Rotary Friction Welding Of Thin-Walled Tubes, Caleb James Brown

Theses and Dissertations

A new model of the material flow in rotary friction welding of tubes is proposed. The material flow proposed is based on 3D scans of welds performed with tungsten tracers. The tracers indicate a bifurcation of flow into two deformation paths. A different analysis is performed on each path.The material in Path 1 interacts with the weld interface and exhibits large amounts of azimuthal flow. Previous analytical investigations that have analytically modelled the weld interface as a non-Newtonian fluid are used to calculate the strain rate in this zone.The material in Path 2 transitions from axial to primarily radial flow. …


Large-Scale Non-Linear Dynamic Optimization For Combining Applications Of Optimal Scheduling And Control, Logan Daniel Beal Dec 2018

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 …


The Effects Of Haptics On Rhythm Dance Game Performance And Enjoyment, Bridger Scott Hodges Dec 2018

The Effects Of Haptics On Rhythm Dance Game Performance And Enjoyment, Bridger Scott Hodges

Theses and Dissertations

Haptics are an exciting, ever-expanding field, particularly in relation to video games. Though haptics found their way rather quickly into conventional games through devices like handheld controllers, music and rhythm titles have hardly seen such attention. Little research has been done to examine the effects of haptics on rhythm dance games from a quantitative and qualitative standpoint for the player. StepMania is an open-source dance game which closely mimics the popular title Dance Dance Revolution. This research investigates the effects of haptics on a sample size of fifty individuals. Each completed three songs in the game with varying conditions: the …


Origami-Based Design Of Fold States And Stability, Alex Avila Dec 2018

Origami-Based Design Of Fold States And Stability, Alex Avila

Theses and Dissertations

Origami is a potentially elegant and powerful source of inspiration for many engineering designs. The viable shapes (fold states) of a single device allow it to perform multiple, seemingly contradictory, functions. The fold state is a large factor in the device's performance, but there are challenges in selecting and maintaining those fold states. In this thesis we analyze existing concepts for overcoming these challenges. Those concepts are compared with those that occur in origami-based devices. From this analysis fundamental gaps were identified, specifically, shortcoming in the terminology used to refer to (1) non-flat origami states and (2) sets of facets …


The Design, Construction, And Thermal Diffusivity Measurements Of The Fluorescent Scanning Thermal Microscope (Fstm), Samuel Hunter Hayden Dec 2018

The Design, Construction, And Thermal Diffusivity Measurements Of The Fluorescent Scanning Thermal Microscope (Fstm), Samuel Hunter Hayden

Theses and Dissertations

Over the life of nuclear fuel, inhomogeneous structures develop, negatively impacting thermal properties. New fuels are under development, but require more accurate knowledge of how the properties change to model performance and determine safe operational conditions. Measurement systems capable of small–scale, pointwise thermal property measurements and low cost are necessary to measure these properties and integrate into hot cells where electronics are likely to fail during fuel investigation. This project develops a cheaper, smaller, and easily replaceable Fluorescent Scanning Thermal Microscope (FSTM) using the blue laser and focusing circuitry from an Xbox HD-DVD player. The FSTM also incorporates novel fluorescent …


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 Dec 2018

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 …


A Flexible Service-Oriented Approach To Address Hydroinformatic Challenges In Large-Scale Hydrologic Predictions, Michael Antonio Souffront Alcantara Dec 2018

A Flexible Service-Oriented Approach To Address Hydroinformatic Challenges In Large-Scale Hydrologic Predictions, Michael Antonio Souffront Alcantara

Theses and Dissertations

Water security is defined as a combination of water for achieving our goals as a society, and an acceptable level of water-related risks. Hydrologic modeling can be used to predict streamflow and aid in the decision-making process with the goal of attaining water security. Developed countries usually have their own hydrologic models; however, developing countries often lack hydrologic models due to factors such as the maintenance, computational costs, and technical capacity needed to run models. A global streamflow prediction system (GSPS) would help decrease vulnerabilities in developing countries and fill gaps in areas where no local models exist by providing …


Pore Pressure Generation And Shear Modulus Degradation During Laminar Shear Box Testing With Prefabricated Vertical Drains, Landon Scott Kinney Dec 2018

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 …


Engineering Cell-Free Biosystems For On-Site Production And Rapid Design Of Next-Generation Therapeutics, Kristen Michelle Wilding Dec 2018

Engineering Cell-Free Biosystems For On-Site Production And Rapid Design Of Next-Generation Therapeutics, Kristen Michelle Wilding

Theses and Dissertations

While protein therapeutics are indispensable in the treatment of a variety of diseases, including cancer, rheumatoid arthritis, and diabetes, key limitations including short half-lives, high immunogenicity, protein instability, and centralized production complicate long-term use and on-demand production. Site-specific polymer conjugation provides a method for mitigating these challenges while minimizing negative impacts on protein activity. However, the location-dependent effects of polymer conjugation are not well understood. Cell-free protein synthesis provides direct access to the synthesis environment and rapid synthesis times, enabling rapid evaluation of multiple conjugation sites on a target protein. Here, work is presented towards developing cell-free protein synthesis as …


Property Localization For Grain Boundary Diffusivity Via Inverse Problem Theory, Christian Kurniawan Dec 2018

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 …


Conceptual Design Of A Pilot-Scale Pressurized Coal-Feed System, Taylor L. Schroedter Dec 2018

Conceptual Design Of A Pilot-Scale Pressurized Coal-Feed System, Taylor L. Schroedter

Theses and Dissertations

This thesis discusses the results and insights gained from developing a CFD model of a pilot-scale pressurized dry coal-feed system using the Barracuda CFD software and modeling various design concepts and operating conditions. The feed system was required to transport approximately 0.00378 kg/s (30 lb/hr) of pulverized coal from a vertical hopper to a 2.07 MPa (20.4 atm or 300 psi) reactor with a CO2-to-coal mass flow ratio of 1-2. Two feed system concepts were developed and tested for coal mass flow, CO2-to-coal mass ratio, steadiness, and uniformity. Piping system components also were evaluated for pressure drop and coal roping.With …


Novel Engineered Porous Materials For The Removal Of Lead From Water, Mohsen Hajipour Hajipour Manjili Dec 2018

Novel Engineered Porous Materials For The Removal Of Lead From Water, Mohsen Hajipour Hajipour Manjili

Theses and Dissertations

The estimated average blood lead level for the population younger than 5 years in the United States is approximately 100 times higher than ancient background levels, indicating that substantial sources of lead exposure exist in the environment. This research is focused on the removal of lead from water with a functionalized zeolite. Functionalization improves adsorption behavior to achieve adsorbent materials with high capacity and stability with potential multiple re-uses.

The lead sorption from water onto an Australian zeolitic mineral (clinoptilolite) unmodified and modified with sulfide-based reagents is investigated with batch and fixed bed column experiments. The effect of solution pH, …


Manufacturing Energy Consumption And Assessment For Us Small And Medium Sized Manufacturers, Yadan Zeng Dec 2018

Manufacturing Energy Consumption And Assessment For Us Small And Medium Sized Manufacturers, Yadan Zeng

Theses and Dissertations

U.S. Manufacturing sector consumes remarkable amount of energy while the energy efficiency is quite low. Energy consumption of CNC machines is significant and various empirical models have been developed to model the Specific Energy Consumption (SEC) of CNC machines. However, most of the models are developed for specific machines, hence have limited applications in manufacturing industry. In this research, a general empirical SEC model for milling machine at certain power level is developed based on actual cutting experimental data. In this model, stand-by power and spindle power are used in the SEC model for the first time. The Material Removal …