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Full-Text Articles in Engineering

Eye-Tracking To Evaluate Trust In Human-Atr Interaction, Samuel Francis Adelman Jan 2020

Eye-Tracking To Evaluate Trust In Human-Atr Interaction, Samuel Francis Adelman

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Human collaboration with targeting aids have allowed analysts to achieve a greater level of coordination and productivity in a variety of fields. This project investigates the impact that an Assisted Target Recognition (ATR) algorithm’s false alarm rate and the task Target of Interest (TOI) level has on user-system trust and use in a targeting decision task. Previous studies suggest that an increased number of false alarms in an ATR task negatively impacts analyst trust in the system. This study will further contribute to this research, aiming to provide a better framework for appropriate tolerance levels within ATR algorithms, utilizing ...


Observing P300 Amplitudes In Multiple Sensory Channels Using Cognitive Probing, Cody Lee Wintermute Jan 2020

Observing P300 Amplitudes In Multiple Sensory Channels Using Cognitive Probing, Cody Lee Wintermute

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High cognitive workload occurs when excessive working memory resources have been deployed to resolve sensory and cognitive processing, resulting in decremented task performance. The P300 event-related potential (ERP) component has shown sensitivity to cognitive load, and it was hypothesized that an attenuated P300 amplitude could be indicative of high cognitive load. We tested this hypothesis by having eight participants complete two continual performance tasks at increasing workload levels while simultaneously performing an oddball task, evoking P300 ERPs in either the auditory or tactile sensory channel. In our experiment, electroencephalographic recordings were collected over the parietal region to observe the P300 ...


Extracting Information From Subroutines Using Static Analysis Semantics, Luke A. Burnett Jan 2020

Extracting Information From Subroutines Using Static Analysis Semantics, Luke A. Burnett

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Understanding how a system component can interact with other services can take an immeasurable amount of time. Reverse engineering embedded and large systems can rely on understanding how components interact with one another. This process is time consuming and can sometimes be generalized through certain behavior.We will be explaining two such complicated systems and highlighting similarities between them. We will show that through static analysis you can capture compiler behavior and apply it to the understanding of a function, reducing the total time required to understand a component of whichever system you are learning.


Topological Analysis Of Averaged Sentence Embeddings, Wesley J. Holmes Jan 2020

Topological Analysis Of Averaged Sentence Embeddings, Wesley J. Holmes

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Sentence embeddings are frequently generated by using complex, pretrained models that were trained on a very general corpus of data. This thesis explores a potential alternative method for generating high-quality sentence embeddings for highly specialized corpora in an efficient manner. A framework for visualizing and analyzing sentence embeddings is developed to help assess the quality of sentence embeddings for a highly specialized corpus of documents related to the 2019 coronavirus epidemic. A Topological Data Analysis (TDA) technique is explored as an alternative method for grouping embeddings for document clustering and topic modeling tasks and is compared to a simple clustering ...


Development Of Real-Time Systems For Supporting Collaborations In Distributed Human And Machine Teams, Aishwarya Bositty Jan 2020

Development Of Real-Time Systems For Supporting Collaborations In Distributed Human And Machine Teams, Aishwarya Bositty

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Real-time distributed systems constitute computing nodes that are connected by a network and coordinate with one another to accomplish a cooperative task, combining the responsiveness, fault-tolerance and geographic independence to support time-constrained collaborative applications, including distributed Human-Machine Teaming. In this thesis research the viability of real-time distributed collaborative technologies is demonstrated through the design, development and validation of prototype systems that support two human-machine teaming scenarios namely, ACE-IMS (Affirmation Cue based Interruption Management Systems) and ReadMI (Real-time Assessment of Dialogue in Motivational Interview). ACE-IMS demonstrates how a combination of AI capabilities and the cloud and mobile computing infrastructure can be ...


Hierarchical Anomaly Detection For Time Series Data, Ryan E. Sperl Jan 2020

Hierarchical Anomaly Detection For Time Series Data, Ryan E. Sperl

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With the rise of Big Data and the Internet of Things, there is an increasing availability of large volumes of real-time streaming data. Unusual occurrences in the underlying system will be reflected in these streams, but any human analysis will quickly become out of date. There is a need for automatic analysis of streaming data capable of identifying these anomalous behaviors as they occur, to give ample time to react. In order to handle many high-velocity data streams, detectors must minimize the processing requirements per value. In this thesis, we have developed a novel anomaly detection method which makes use ...


Improving Pain Management In Patients With Sickle Cell Disease Using Machine Learning Techniques, Fan Yang Jan 2020

Improving Pain Management In Patients With Sickle Cell Disease Using Machine Learning Techniques, Fan Yang

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Sickle cell disease (SCD) is an inherited red blood cell disorder that can cause a multitude of complications throughout a patient's life. Pain is the most common complication and a significant cause of morbidity. Since pain is a highly subjective experience, both medical providers and patients express difficulty in determining ideal treatment and management strategies for pain. Therefore, the development of objective pain assessment and pain forecasting methods is critical to pain management in SCD. On the other hand, the rapidly increasing use of mobile health (mHealth) technology and wearable devices gives the ability to build a remote health ...


Finding Data Races In Software Binaries With Symbolic Execution, Nathan D. Jackson Jan 2020

Finding Data Races In Software Binaries With Symbolic Execution, Nathan D. Jackson

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Modern software applications frequently make use of multithreading to utilize hardware resources better and promote application responsiveness. In these applications, threads share the program state, and synchronization mechanisms ensure proper ordering of accesses to the program state. When a developer fails to implement synchronization mechanisms, data races may occur. Finding data races in an automated way is an already challenging problem, but often impractical without source code or understanding how to execute the program under analysis. In this thesis, we propose a solution for finding data races on software binaries and present our prototype implementation BINRELAY. Our solution makes use ...


Enabling Static Program Analysis Using A Graph Database, Jialun Liu Jan 2020

Enabling Static Program Analysis Using A Graph Database, Jialun Liu

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This thesis presents the design, the implementation, and the evaluation of a database-oriented static program analysis engine for the PHP programming language. This engine analyzes PHP programs by representing their semantics using a graph-based data structure, which will be subsequently stored into a graph database. Such scheme will fundamentally facilitate various program analysis tasks such as static taint analysis, visualization, and data mining. Specifically, these complex program analysis tasks can now be translated into built-in declarative graph database operations with rich features. Our engine fundamentally differs from other existing static program analysis systems that mainly leverage intermediate representation (IRs) to ...


Geoaware - A Simulation-Based Framework For Synthetic Trajectory Generation From Mobility Patterns, Jameson D. Morgan Jan 2020

Geoaware - A Simulation-Based Framework For Synthetic Trajectory Generation From Mobility Patterns, Jameson D. Morgan

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Recent advances in location acquisition services have resulted in vast amounts of trajectory data; providing valuable insight into human mobility. The field of trajectory data mining has exploded as a result, with literature detailing algorithms for (pre)processing, map matching, pattern mining, and the like. Unfortunately, obtaining trajectory data for the design and evaluation of such algorithms is problematic due to privacy, ethical, dataset size, researcher access, and sampling frequency concerns. Synthetic trajectories provide a solution to such a problem as they are cheap to produce and are derived from a fully controllable generation procedure. Citing deficiencies in modern synthetic ...


Design And Simulation Of Boost Dc - Dc Pulse Width Modulator (Pwm) Feed-Forward Control Converter, Calenia L. Franklin Jan 2020

Design And Simulation Of Boost Dc - Dc Pulse Width Modulator (Pwm) Feed-Forward Control Converter, Calenia L. Franklin

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Military aircraft systems’ power losses are occurring during the loading operations; loading and unloading causes the aircraft systems to lose power. The primary aircraft power source is provided by a 400Hz Ground Power Units (GPU). This GPU provides power to interior lighting, the aircraft cargo compartment, and other electrical systems (i.e. bus). The issues are during loading and unloading on the aircraft, which causes dropout of aircraft power supplied by the external 400Hz GPU. The majority of the military aircraft require a high voltage and a high current with a 270V power output. This thesis analyzes using Feed-Forward PWM ...


Stream Clustering And Visualization Of Geotagged Text Data For Crisis Management, Nathaniel C. Crossman Jan 2020

Stream Clustering And Visualization Of Geotagged Text Data For Crisis Management, Nathaniel C. Crossman

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In the last decade, the advent of social media and microblogging services have inevitably changed our world. These services produce vast amounts of streaming data, and one of the most important ways of analyzing and discovering interesting trends in the streaming data is through clustering. In clustering streaming data, it is desirable to perform a single pass over incoming data, such that we do not need to process old data again, and the clustering model should evolve over time not to lose any important feature statistics of the data. In this research, we have developed a new clustering system that ...


Design Of A Novel Wearable Ultrasound Vest For Autonomous Monitoring Of The Heart Using Machine Learning, Garrett G. Goodman Jan 2020

Design Of A Novel Wearable Ultrasound Vest For Autonomous Monitoring Of The Heart Using Machine Learning, Garrett G. Goodman

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As the population of older individuals increases worldwide, the number of people with cardiovascular issues and diseases is also increasing. The rate at which individuals in the United States of America and worldwide that succumb to Cardiovascular Disease (CVD) is rising as well. Approximately 2,303 Americans die to some form of CVD per day according to the American Heart Association. Furthermore, the Center for Disease Control and Prevention states that 647,000 Americans die yearly due to some form of CVD, which equates to one person every 37 seconds. Finally, the World Health Organization reports that the number one ...


An Adversarial Framework For Deep 3d Target Template Generation, Walter E. Waldow Jan 2020

An Adversarial Framework For Deep 3d Target Template Generation, Walter E. Waldow

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This paper presents a framework for the generation of 3D models. This is an important problem for many reasons. For example, 3D models are important for systems that are involved in target recognition. These systems use 3D models to train up accuracy on identifying real world object. Traditional means of gathering 3D models have limitations that the generation of 3D models can help overcome. The framework uses a novel generative adversarial network (GAN) that learns latent representations of two dimensional views of a model to bootstrap the network’s ability to learn to generate three dimensional objects. The novel architecture ...


Comparing Rf Fingerprinting Performance Of Hobbyist And Commercial-Grade Sdrs, Travis R. Smith Jan 2020

Comparing Rf Fingerprinting Performance Of Hobbyist And Commercial-Grade Sdrs, Travis R. Smith

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Radio Frequency Fingerprinting (RFF) research typically uses expensive, laboratory grade receivers which have high dynamic range, very stable oscillators, large instantaneous bandwidth, multi-rate sampling, etc. In this study, the RFF effectiveness of lower grade receivers is considered. Using software-defined radios (SDRs) of different cost and performance, a linear regression model is developed to predict RFF performance. Unlike two previous studies of SDR effectiveness that used commercial and lab-grade SDRs, the experiment here focused on hobbyist and commercial-grade SDRs (RTL-SDR, B200-mini, N210). A regression model is proposed for a generic SDR. Using a full-factorial experiment matrix, the gain, sample rate, and ...


Predicting Subjective Sleep Quality Using Objective Measurements In Older Adults, Reza Sadeghi Jan 2020

Predicting Subjective Sleep Quality Using Objective Measurements In Older Adults, Reza Sadeghi

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Humans spend almost a third of their lives asleep. Sleep has a pivotal effect on job performance, memory, fatigue recovery, and both mental and physical health. Sleep quality (SQ) is a subjective experience and reported via patients’ self-reports. Predicting subjective SQ based on objective measurements can enhance diagnosis and treatment of SQ defects, especially in older adults who are subject to poor SQ. In this dissertation, we assessed enhancement of subjective SQ prediction using an easy-to-use E4 wearable device, machine learning techniques and identifying disease-specific risk factors of abnormal SQ in older adults. First, we designed a clinical decision support ...


Quadrotor Uav Flight Control With Integrated Mapping And Path Planning Capabilities, Jason A. Gauthier Jan 2020

Quadrotor Uav Flight Control With Integrated Mapping And Path Planning Capabilities, Jason A. Gauthier

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Quadrotor UAVs have become a common and easily acquirable hardware platform for research and development with control laws, mapping systems, and path planning. In this research, a non-linear model of a quadrotor UAV is linearized with model parameters being identified using collected flight data. The PID, LQR, and backstepping control laws are implemented. An adaptive control law is also implemented to handle the loss of effectiveness in motor actuation. Additionally, this research also implements a laser-based SLAM algorithm for mapping and localization in an unknown two-dimensional environment. Path planning and obstacle avoidance algorithms are implemented onboard using the Robot Operating ...


Quantitative Susceptibility Mapping (Qsm) Reconstruction From Mri Phase Data, Sara Gharabaghi Jan 2020

Quantitative Susceptibility Mapping (Qsm) Reconstruction From Mri Phase Data, Sara Gharabaghi

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Quantitative susceptibility mapping (QSM) is a powerful technique that reveals changes in the underlying tissue susceptibility distribution. It can be used to measure the concentrations of iron and calcium in the brain both of which are linked with numerous neurodegenerative diseases. However, reconstructing the QSM image from the MRI phase data is an ill-posed inverse problem. Different methods have been proposed to overcome this difficulty. Still, the reconstructed QSM images suffer from streaking artifacts and underestimate the measured susceptibility of deep gray matter, veins, and other high susceptibility regions. This thesis proposes a structurally constrained Susceptibility Weighted Imaging and Mapping ...


Identifying Knowledge Gaps Using A Graph-Based Knowledge Representation, Daniel P. Schmidt Jan 2020

Identifying Knowledge Gaps Using A Graph-Based Knowledge Representation, Daniel P. Schmidt

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Knowledge integration and knowledge bases are becoming more and more prevalent in the systems we use every day. When developing these knowledge bases, it is important to ensure the correctness of the information upon entry, as well as allow queries of all sorts; for this, understanding where the gaps in knowledge can arise is critical. This thesis proposes a descriptive taxonomy of knowledge gaps, along with a framework for automated detection and resolution of some of those gaps. Additionally, the effectiveness of this framework is evaluated in terms of successful responses to queries on a knowledge base constructed from a ...


Analytical Approach To Multi-Objective Joint Inference Control For Fixed Wing Unmanned Aerial Vehicles, Julian L. Casey Jan 2020

Analytical Approach To Multi-Objective Joint Inference Control For Fixed Wing Unmanned Aerial Vehicles, Julian L. Casey

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Fixed-wing Unmanned Aerial Vehicles (UAVs) have been found highly useful in various environments, including military and law enforcement. With the increased use of fixed-wing UAVs, there becomes an increased need to optimize the resources available. One approach to resource management is to create multi-objective flights. This thesis presents the design, analysis, and experimental implementation of multi-objective resource management for the resource of Range, distance available to the UAV, from the viewpoint of Intelligence Surveillance and Reconnaissance (ISR). First, a Simulation Environment is created capable of tracking multiple fixed-wing UAVs and to allow for the UAVs’ being controlled by an externally ...


Ab Initio Modeling Of An Electron Transport Layer Interface In Hybrid Perovskite Solar Cells, Krantikumar Subhash Pawar Jan 2020

Ab Initio Modeling Of An Electron Transport Layer Interface In Hybrid Perovskite Solar Cells, Krantikumar Subhash Pawar

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Hybrid organic-inorganic perovskite solar cell is an emerging technology which has shown the fastest advancement in power conversion efficiency within a few years since introduction, thus making it one of the clean energy breakthroughs. These cells are based on thin-film technology which makes them suitable to manufacture using low-cost solution processing methods. As these types of cells are easily tunable with the selection of different materials, interfacial engineering is an important approach to increasing their efficiency. One of the main hurdles in this regard is the loss caused by the recombination of separated charges. An approach to tackle these issues ...


Global Joint Registry: Analysis Of Revision Hip Arthroplasty Data, Alicia M. Runser Jan 2020

Global Joint Registry: Analysis Of Revision Hip Arthroplasty Data, Alicia M. Runser

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Total hip arthroplasty (THA) has become well-known as being one of the most successful procedures with much long-term positive clinical results. However, revision surgeries are still required. The four most common failure modes for THAs, “reasons for revision”, are loosening, dislocation or instability, fracture, and infection. The goal of a hip arthroplasty register is to gather information on patients that undergo a total hip arthroplasty and factors pertaining to their surgery which may affect their outcome for future years such as the reason for revision. Analysis of this data can help with the allocation of healthcare funds and the efficacy ...


Online Clustering With Bayesian Nonparametrics, Matthew D. Scherreik Jan 2020

Online Clustering With Bayesian Nonparametrics, Matthew D. Scherreik

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Clustering algorithms, such as Gaussian mixture models and K-means, often require the number of clusters to be specified a priori. Bayesian nonparametric (BNP) methods avoid this problem by specifying a prior distribution over the cluster assignments that allows the number of clusters to be inferred from the data. This can be especially useful for online clustering tasks, where data arrives in a continuous stream and the number of clusters may dynamically change over time. Classical BNP priors often overestimate the number of clusters, however, leading researchers to develop new priors with more control over this tendency. To date, BNP algorithms ...


Logistic Function Based Nonlinear Modeling And Circuit Analysis Of The Bipolar Vacancy Migration Memristor, Isaac P. Abraham Jan 2020

Logistic Function Based Nonlinear Modeling And Circuit Analysis Of The Bipolar Vacancy Migration Memristor, Isaac P. Abraham

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Memristor is an acronym for memory resistor. Memristors promise to be building blocks for high density memory and analog computation. Hewlett Packard’s announcement in 2008 of having fabricated a memristor on an integrated circuit scale has created a tangible excitement in this field. Understanding and exploiting the full potential of these devices requires good compact models. Symbolic modeling provides a balance between achieving accurate empirical fit and generating closed form expressions. This dissertation simplifies the transport equation into a variable coefficient advection equation, very similar to a Burgers’ equation traditionally used in fluid dynamics. The Burgers’-like model reveals ...


Mitigating Atmospheric Phase Errors In Sal Data, Randy S. Depoy Jr. Jan 2020

Mitigating Atmospheric Phase Errors In Sal Data, Randy S. Depoy Jr.

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Synthetic aperture ladar (SAL) is an emerging remote sensing technology capable of providing high-resolution, interpretable, and timely imagery. SAL and synthetic aperture radar (SAR) are similar in that they provide high-resolution imagery suitable for a wide-variety of applications beyond the diffraction limit of the real aperture. Several advantages of SAL are; realistic imagery resulting from diffuse scattering of optically-rough objects, fine directionality of laser beam making the technology inherently low probability-of-detect, and shorter synthetic aperture collection times, all of which result from operating at optical as opposed to RF wavelengths. With the dramatic decrease in wavelength, SAL systems become more ...


Computational Assessment Of Aortic Valve Function And Mechanics Under Hypertension, Saurav Kadel Jan 2020

Computational Assessment Of Aortic Valve Function And Mechanics Under Hypertension, Saurav Kadel

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Calcific aortic valve disease (CAVD), the most common valvular heart disorder, is associated with complications such as stroke, heart attack, aortic aneurysm, left ventricular hypertrophy, and ultimately death. While hypertension has been identified as a major risk factor for CAVD, the mechanisms by which it may promote calcification are still unknown. Given the sensitivity of valvular tissue to mechanical stress alterations, the hemodynamic abnormalities linked to hypertension may play a role in the development of CAVD. Further, the effects of hypertension on the left ventricular functionality and coronary flow resistance remain largely uninvestigated. Hence, the objectives of this thesis were ...


Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey Jan 2020

Correlating In-Situ Monitoring Data With Internal Defects In Laser Powder Bed Fusion Additive Manufacturing, Andrew J. Harvey

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The presence of defects within laser powder bed fusion (LPBF) parts can lead to reduced mechanical properties and life of components. Because of this, the ability to detect these defects within the parts is critical before the part is subject to its intended loading. Normally the parts are subjected to a quality analysis once they are completed however, this process is typically expensive and time consuming. A solution for these problems is to sense the creation of defects and pores in the parts in-situ, while the part is being fabricated. One proposed method of in-situ monitoring is visible spectroscopy to ...


Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle Jan 2020

Stabilization Of Β-Cristobalite In The Sio2-Alpo4-Bpo4 System, Kathryn Doyle

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Fused silica (silica glass) is transparent in the optical and near-infrared and has a low dielectric constant, making it suitable as a window material for radio frequency radiation. However, at high temperatures (>1100C), fused silica will easily creep and lose dimensional stability. Crystallized silica is much more creep resistant than fused silica. Silica crystallizes to many different structures including quartz, tridymite, and α- and β cristobalite. The only cubic polymorph, which is suitable for both optical and radio frequency transmission in polycrystalline form, is β -cristobalite. Unfortunately, this polymorph transforms to α-cristobalite at ~300C, and the volume change during this ...


Optimization Study Of A Combined Wind-Solar Farm For A Specified Demand, Venkat Siddhartha Rama Jan 2020

Optimization Study Of A Combined Wind-Solar Farm For A Specified Demand, Venkat Siddhartha Rama

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At the present time, using wind and solar energy for producing electricity in the United States is becoming cost competitive. According to Lazard’s 2019 [36] levelized cost of energy (LCOE) analysis of a number of energy sources used for producing electricity in the United States, wind and solar are cheaper than natural gas and coal. While capital, maintenance, operation, and fuel costs are included in LCOE numbers, energy source intermittency is not. Intermittency is an important issue with wind and solar energy sources, but not with natural gas or coal energy sources. Combining wind and solar energy sources into ...


Metal Coupon Testing In An Axial Rotating Detonation Engine For Wear Characterization, Gary S. North Jan 2020

Metal Coupon Testing In An Axial Rotating Detonation Engine For Wear Characterization, Gary S. North

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Rotating Detonation Engines (RDE) are being explored as a possible way to get better fuel efficiency for turbine engines than is otherwise possible. The walls of the RDE are subjected to cyclic thermal and mechanical shock loading at rates of approximately 3 KHz, with gas temperatures as high as 2976 K. This project performed testing with Inconel 625 and 304 stainless steel coupons in an RDE outer body to attempt to measure material ablation rates. Significant microstructural changes were observed to include grain growth in both alloys, carbide formation and grain boundary melting in Inconel, and formation of delta ferrite ...