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Evaluation Of Consumer Drone Control Interface, Thomas William Merrell Jan 2018

Evaluation Of Consumer Drone Control Interface, Thomas William Merrell

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The development and use of consumer grade drones is becoming a larger part of our society for many different applications. There has been a great amount of discussion and constant review of proper operation of consumer drones including proper methods of control. In turn, regulation of such devices has been inconsistent. This study aims to better understand the effects of the three primary control interface methods (line of sight, video aided, and first-person view) on flight performance, situational awareness, and perceived mental workload of the operator. Secondarily, this study aims to provide design recommendations for future interfaces. This study shows ...


M1 To M2 Macrophage Induction Using Retinoic Acid And Mesenchymal Stem Cells Loaded On An Electrospun Pullulan/Gelatin Scaffold To Promote Healing Of Chronic Wounds, Kaivon Assani Jan 2018

M1 To M2 Macrophage Induction Using Retinoic Acid And Mesenchymal Stem Cells Loaded On An Electrospun Pullulan/Gelatin Scaffold To Promote Healing Of Chronic Wounds, Kaivon Assani

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Modulation of macrophage polarization is required for effective tissue repair and regenerative therapies. Conversion of macrophages from inflammatory M1 to fibrotic M2 phenotype could help in diseases such as chronic wound which are stuck in inflammatory state. During the inflammatory phase, macrophages are of the inflammatory phenotype (M1) and distribute pro-inflammatory cytokines including TNF-a and IL1[beta] which are microbicidal and recruit/activate cells. In normal wound healing macrophages then switch to a fibrotic phenotype (M2) promoting wound closure by angiogenesis, and matrix deposition. Chronic wounds are a major biological and financial burden to both patients and the health care ...


Building An Abstract-Syntax-Tree-Oriented Symbolic Execution Engine For Php Programs, Jin Huang Jan 2018

Building An Abstract-Syntax-Tree-Oriented Symbolic Execution Engine For Php Programs, Jin Huang

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This thesis presents the design, implementation, and evaluation of an abstract-syntax-tree-oriented symbolic execution engine for the PHP programming language. As a symbolic execution engine, our system emulate the execution of a PHP program by assuming that all inputs are with symbolic rather than concrete values. While our system inherits the basic definition of symbolic execution, it fundamentally differs from existing symbolic execution implementations that mainly leverage intermediate representation (IRs) to operate. Specifically, our system directly takes the abstract syntax tree (AST) of a program as input and subsequently interprets this AST. Performing symbolic execution using AST offers unique advantages. First ...


Image Stitching And Matching Tool In The Automated Iterative Reverse Engineer (Aire) Integrated Circuit Analysis Suite, David C. Bowman Jan 2018

Image Stitching And Matching Tool In The Automated Iterative Reverse Engineer (Aire) Integrated Circuit Analysis Suite, David C. Bowman

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Due to current market forces, leading-edge semiconductor fabrication plants have moved outside of the US. While this is not a problem at first glance, when it comes to security-sensitive applications, over-production, device cloning, or design alteration becomes a possibility. Since these vulnerabilities exist during the fabrication phase, a Reverse Engineering (RE) step must be introduced to help ensure secure device operation. This thesis proposes several unique methods and a collection of tools to ensure trust assurance in integrated circuit design by detecting fabrication flaws and possible hardware Trojans using several image processing techniques; fused into a singular view of the ...


Real-Time Path Planning And Obstacle Avoidance For Mobile Robots With Actuator Faults, Ravindra Vibha Bellur Jan 2018

Real-Time Path Planning And Obstacle Avoidance For Mobile Robots With Actuator Faults, Ravindra Vibha Bellur

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In this research, a fault-tolerant path planning and obstacle avoidance algorithm is implemented for mobile ground robots. The fault-tolerant system architecture consists of the following three components: (1) an online fault diagnosis module for detecting and estimating actuator faults in the mobile robot; (2) a localization and mapping module for dynamic terrain mapping and obstacle detection; (3) a path planning and obstacle avoidance module for generating way points from a given point to the desired destination, avoiding the detected obstacles and moving along these way points. The online fault diagnostic information is used to compensate for the effect of faults ...


A Simulation Method For Studying Effects Of Site-Specific Clutter On Sar-Gmti Performance, Marcus James Campbell Jan 2018

A Simulation Method For Studying Effects Of Site-Specific Clutter On Sar-Gmti Performance, Marcus James Campbell

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Synthetic aperture radar (SAR) is an invaluable tool for detection of ground moving targets when combined with processing techniques of ground moving target indication (GMTI). This work investigates a simulation methodology for studying impact of site-specific ground clutter on SAR-GMTI performance. A terrain model is proposed and is based on digital terrain elevation data (DTED) and national land-use land-cover data (NLCD) as provided by the US Geological Survey. The proposed physical optics simulation method capitalizes on high-fidelity digital target models in combination with the proposed terrain model. SAR phase history is generated for a moving commercial target in situ of ...


Design Of A Novel Tissue Culture System To Subject Aortic Tissue To Multidirectional Bicuspid Aortic Valve Wall Shear Stress, Janet Liu Jan 2018

Design Of A Novel Tissue Culture System To Subject Aortic Tissue To Multidirectional Bicuspid Aortic Valve Wall Shear Stress, Janet Liu

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Blood vessels experience complex hemodynamics marked by three-dimensionality and pulsatility. Arterial endothelial cells interact with the characteristics of the fluid wall shear stress (WSS) to maintain homeostasis or promote disease states. In particular, the bicuspid aortic valve (BAV), a congenital heart valve anatomy consisting of two leaflets instead of three, is associated with aortic complications presumably promoted by hemodynamic abnormalities. While devices have been used to test this hypothesis, their capabilities are limited to the generation of time-varying WSS magnitude in one direction. However, the increased flow helicity generated by BAVs in the aorta is expected to result in increased ...


In Vitro Assessment Of The Effects Of Valvular Stenosis On Aorta Hemodynamics And Left Ventricular Function, Ashish Madan Jan 2018

In Vitro Assessment Of The Effects Of Valvular Stenosis On Aorta Hemodynamics And Left Ventricular Function, Ashish Madan

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Calcific aortic stenosis (CAS) is the most common valvular heart disease and is associated with aortopathy and ventricular dysfunction. Hemodynamic alterations due CAS could affect the aorta lining (endothelium), that is in direct contact with the blood, triggering adverse biological responses that may possibly cause aortic dilation and dissection. Also, CAS could impose excessive ventricular load leading to ventricular wall thickening, thus putting an individual at a higher risk of heart attack or stroke. These pathophysiological effects of CAS are highly dependent on the degree of calcification. However, the impact of CAS development on aorta flow and left ventricular workload ...


Analysis Of Evolutionary Algorithms In The Control Of Path Planning Problems, Pavlos Androulakakis Jan 2018

Analysis Of Evolutionary Algorithms In The Control Of Path Planning Problems, Pavlos Androulakakis

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The purpose of this thesis is to examine the ability of evolutionary algorithms (EAs) to develop near optimal solutions to three different path planning control problems. First, we begin by examining the evolution of an open-loop controller for the turn-circle intercept problem. We then extend the evolutionary methodology to develop a solution to the closedloop Dubins Vehicle problem. Finally, we attempt to evolve a closed-loop solution to the turn constrained pursuit evasion problem. For each of the presented problems, a custom controller representation is used. The goal of using custom controller representations (as opposed to more standard techniques such as ...


Measurement Of Unsteady Characteristics Of Endwall Vortices Using Surface-Mounted Hot-Film Sensors, Emma Michelle Veley Jan 2018

Measurement Of Unsteady Characteristics Of Endwall Vortices Using Surface-Mounted Hot-Film Sensors, Emma Michelle Veley

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High-lift low-pressure turbine blades produce significant losses at the junction with the endwall. The losses are caused by several complex three-dimensional vortical flow structures, which interact with the blade suction surface boundary layer. This study investigates the unsteady characteristics of these endwall flow structures on a highly loaded research profile and the adjacent endwall using surface-mounted hot-film sensors. Experiments were conducted in a low-speed linear cascade wind tunnel. The front-loaded blade profile was subjected to three different inlet conditions, consisting of two turbulence levels, and three incoming boundary layer thicknesses. Multiple surface-mounted hot-film sensors were installed throughout the passage. This ...


Impact Of Near-Field-To-Far-Field Transformation On Sar Images Formed In An Indoor Non-Anechoic Environment, Jacob D. Compaleo Jan 2018

Impact Of Near-Field-To-Far-Field Transformation On Sar Images Formed In An Indoor Non-Anechoic Environment, Jacob D. Compaleo

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This work investigates the impact of the near-field-to-far-field transformation (NFFFT) algorithm on phase history measurement collections completed in the Sensors and Signals Exploitation Laboratory (SSEL). SSEL is an indoor non-anechoic environ- ment that is at risk to some measurement interferences such as multiple bounces. Complete 360-degree phase history measurements of scale model aircraft are con- ducted at varying range values within the near-field limit. These measurements are calibrated with the Mie series scattering solution for a sphere. After calibration, the measurements are transformed using the NFFFT, with radar cross-section (RCS) estimated. RCS of the transformed data is compared with the ...


Content-Based Clustering And Visualization Of Social Media Text Messages, Sydney A. Barnard Jan 2018

Content-Based Clustering And Visualization Of Social Media Text Messages, Sydney A. Barnard

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Although Twitter has been around for more than ten years, crisis management agencies and first response personnel are not able to fully use the information this type of data provides during a crisis or natural disaster. This thesis addresses clustering and visualizing social media data by textual similarity, rather than by only time and location, as a tool for first responders. This thesis presents a tool that automatically clusters geotagged text data based on their content and displays the clusters and their locations on the map. It allows at-a-glance information to be displayed throughout the evolution of a crisis. For ...


A Semantically Enhanced Approach To Identify Depression-Indicative Symptoms Using Twitter Data, Ankita Saxena Jan 2018

A Semantically Enhanced Approach To Identify Depression-Indicative Symptoms Using Twitter Data, Ankita Saxena

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According to the World Health Organization, more than 300 million people suffer from Major Depressive Disorder (MDD) worldwide. PHQ-9 is used to screen and diagnose MDD clinically and identify its severity. With the unprecedented growth and enthusiastic acceptance of social media such as Twitter, a large number of people have come to share their feelings and emotions on it openly. Each tweet can indicate a user's opinion, thought or feeling. A tweet can also indicate multiple symptoms related to PHQ-9. Identifying PHQ-9 symptoms indicated by a tweet can provide crucial information about a user regarding his/her depression diagnosis ...


A Twitter-Based Study For Understanding Public Reaction On Zika Virus, Roopteja Muppalla Jan 2018

A Twitter-Based Study For Understanding Public Reaction On Zika Virus, Roopteja Muppalla

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In recent times, social media platforms like Twitter have become more popular and people have become more interactive and responsive than before. People often react to every news in real-time and within no-time, the information spreads rapidly. Even with viral diseases like Zika, people tend to share their opinions and concerns on social media. This can be leveraged by the health officials to track the disease in real-time thereby reducing the time lag due to traditional surveys. A faster and accurate detection of the disease can allow health officials to understand people's opinion of the disease and take necessary ...


Multiscale Modeling Of Hemodynamics In Human Vessel Network And Its Applications In Cerebral Aneurysms, Hongtao Yu Jan 2018

Multiscale Modeling Of Hemodynamics In Human Vessel Network And Its Applications In Cerebral Aneurysms, Hongtao Yu

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Three-dimensional (3D) simulation of patient-specific morphological models has been widely used to provide the hemodynamic information of individual patients, such as wall shear stress (WSS), oscillatory shear index (OSI), and flow patterns, etc. Since patient-specific morphological segment was only restricted locally, boundary conditions (BCs) are required to implement the CFD simulation. Direct measurements of the flow and pressure waveforms were often required as input BCs for 3D CFD simulations of patient-specific models. However, as the morphology develops, the feedback from this topological deformation may lead to BCs being altered, and hence without this feedback, the flow characteristics of the morphology ...


Demonstrating The Functionality And Efficacy Of Blockchain-Based System In Healthcare Using Simulation Tools, Jad S. Mubaslat Jan 2018

Demonstrating The Functionality And Efficacy Of Blockchain-Based System In Healthcare Using Simulation Tools, Jad S. Mubaslat

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Blockchain and cryptocurrencies have been a rapidly growing industry and area of academic research since Bitcoin's launch in early 2009. Blockchains have already been applied in spaces outside of finance, such as healthcare. This work explores the Bitcoin blockchain and a blockchain-based care coordination system through the use of modeling and simulation tools. Two agent based models are constructed: one to represent the Bitcoin blockchain, and a second to represent a blockchain-based care coordination system, MDChain. Insight is provided that is relevant to current issues within the Bitcoin community and predictions are made as to its future. The feasibility ...


A Stochastic Petri Net Reverse Engineering Methodology For Deep Understanding Of Technical Documents, Giorgia Rematska Jan 2018

A Stochastic Petri Net Reverse Engineering Methodology For Deep Understanding Of Technical Documents, Giorgia Rematska

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Systems Reverse Engineering has gained great attention over time and is associated with numerous different research areas. The importance of this research derives from several technological necessities. Security analysis and learning purposes are two of them and can greatly benefit from reverse engineering. More specifically, reverse engineering of technical documents for deeper automatic understanding is a research area where reverse engineering can contribute a lot. In this PhD dissertation we develop a novel reverse engineering methodology for deep understanding of architectural description of digital hardware systems that appear in technical documents. Initially, we offer a survey on reverse engineering of ...


Domain-Specific Knowledge Extraction From The Web Of Data, Sarasi Lalithsena Jan 2018

Domain-Specific Knowledge Extraction From The Web Of Data, Sarasi Lalithsena

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Domain knowledge plays a significant role in powering a number of intelligent applications such as entity recommendation, question answering, data analytics, and knowledge discovery. Recent advances in Artificial Intelligence and Semantic Web communities have contributed to the representation and creation of this domain knowledge in a machine-readable form. This has resulted in a large collection of structured datasets on the Web which is commonly referred to as the Web of data. The Web of data continues to grow rapidly since its inception, which poses a number of challenges in developing intelligent applications that can benefit from its use. Majority of ...


Fabrication And Characterizations Of Lagp/Peo Composite Electrolytes For All Solid-State Lithium-Ion Batteries, Jeremy J. Lee Jan 2018

Fabrication And Characterizations Of Lagp/Peo Composite Electrolytes For All Solid-State Lithium-Ion Batteries, Jeremy J. Lee

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With the rise of electric vehicles and increasing dependence on mobile electronics, the demands for lithium-ion batteries have followed in tandem for their high energy and power densities. However, traditional lithium-ion batteries consisting of liquid electrolytes have limited operating temperatures and are susceptible to ignition and subsequent fires. Recently, battery research has diverged into solid state chemistry to address the aforementioned issues. In this research, we systematically investigate a series of ceramic/polymer lithium-ion conducting composite electrolytes, i.e. Li1.4Al0.4Ge1.6(PO4)3 /lithiated polyethylene oxide (LAGP/PEO). Lithiated PEO was prepared with two different lithium salts, LiBF4 ...


Augmenting Incident Command System For Improved Emergency Response, Meenakshi Nagarajan Jan 2018

Augmenting Incident Command System For Improved Emergency Response, Meenakshi Nagarajan

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Incident Command System provides a framework for commanders to manage an incident. However, maintaining good situation awareness in an emergency situation is often challenging to the Incident Commander. Stress may result in task fixation which may cause the commander to miss critical information and can eventually lead to poor decisions. The proposed augmented decision support system, with an integrated knowledge base, enhances the commander's decision making and situation awareness by presenting the information that may have been missed. The system has been evaluated to investigate its utility in chemical hazard scenarios. The system was used by experienced Incident Commanders ...


Slim Embedding Layers For Recurrent Neural Language Models, Zhongliang Li Jan 2018

Slim Embedding Layers For Recurrent Neural Language Models, Zhongliang Li

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Recurrent neural language (RNN) models are the state-of-the-art method for language modeling. When the vocabulary size is large, the space taken to store the model parameters becomes the bottleneck for the use of these type of models. We introduce a simple space compression method that stochastically shares the structured parameters at both the input and output embedding layers of RNN models to significantly reduce the size of model parameters, but still compactly represents the original input and the output embedding layers. The method is easy to implement and tune. Experiments on several data sets show that the new method achieves ...


Measuring Goal Similarity Using Concept, Context And Task Features, Vahid Eyorokon Jan 2018

Measuring Goal Similarity Using Concept, Context And Task Features, Vahid Eyorokon

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Goals can be described as the user's desired state of the agent and the world and are satisfied when the agent and the world are altered in such a way that the present state matches the desired state. For physical agents, they must act in the world to alter it in a series of individual atomic actions. Traditionally, agents use planning to create a chain of actions each of which altering the current world state and yielding a new one until the final action yields the desired goal state. Once this goal state has been achieved, the goal is ...


A Robust Low Power Static Random Access Memory Cell Design, A. V. Rama Raju Pusapati Jan 2018

A Robust Low Power Static Random Access Memory Cell Design, A. V. Rama Raju Pusapati

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Stability of a Static Random Access Memory (SRAM) cell is an important factor when considering an SRAM cell for any application. The Static Noise Margin (SNM) of a cell, which determines the stability, varies under different operating conditions. Based on the performance of three existing SRAM cell designs, 6T, 8T and 10T, a 10 Transistor SRAM cell is proposed which has good stability and has the advantage of reduced read power when compared to 6T and 8T SRAM cells. The proposed 10T SRAM cell has a single-ended read circuit which improves SNM over the 6T cell. The proposed 10T cell ...


Design Optimization Of A Non-Axisymmetric Endwall Contour For A High-Lift Low Pressure Turbine Blade, Jacob Allen Dickel Jan 2018

Design Optimization Of A Non-Axisymmetric Endwall Contour For A High-Lift Low Pressure Turbine Blade, Jacob Allen Dickel

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Various approaches have been used to shape the geometry at the junction of the endwall and the blade profile in high-lift low-pressure turbine passages in order to reduce the endwall losses. This thesis will detail the workflow to produce an optimized non-axisymmetric endwall contour design for a front-loaded high-lift research turbine profile. Validation of the workflow was performed and included a baseline planar and test contour case for a future optimization study. Endwall contours were defined using a series of Bezier curves across the passage to create a smooth surface. A parametric based approach was used to develop the test ...


Fpga-Based Ir Localization Sensor, Samuel I. Susanto Jan 2018

Fpga-Based Ir Localization Sensor, Samuel I. Susanto

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Pursuit-evasion scenarios are common in both natural and man-made systems. Often times, the pursuer and evader maneuver in response to each others actions using relative information based on the geometry of the agents and potential obstacles within the environment. The pursuer needs the target's bearing angle in order to plan a trajectory or path to capture it. We propose an FPGA-based infrared sensor array to detect up to 6 agents' bearing angles simultaneously. The final output of the sensor is the bearing angle of other agents. The sensor was tested and validated experimentally. Implementing the sensor and transmitter pair ...


Virtual Doctor: An Intelligent Human-Computer Dialogue System For Quick Response To People In Need, Stavros Mallios Jan 2018

Virtual Doctor: An Intelligent Human-Computer Dialogue System For Quick Response To People In Need, Stavros Mallios

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One of the challenges of our society is the existence of chronic-related conditions and diseases among the elderly and people at risk. Apart from the welfare of people, a significant impact of this phenomenon is the accumulation of high financial costs for both individuals and health care systems. In order to address this issue and to reduce its effects, many efforts have been made towards preventing, identifying in early stages and, generally, managing chronic-related medical conditions and diseases. As a result, there has been a keen research and market interest in health monitoring devices during the past few decades. Nevertheless ...


Impact Of Noise Level On Task Performance And Workload And Correlation To Personality, Kaylee Marie Eakins Jan 2018

Impact Of Noise Level On Task Performance And Workload And Correlation To Personality, Kaylee Marie Eakins

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An ideal work environment supports a culture of high performance, low mental workload, and quick turnarounds. The impact of noise on three types of tasks in a lab work environment were examined while attempting to identify correlations between a subject's personality and their tolerance to noise. Neuroticism, agreeableness, conscientiousness, and extroversion correlated significantly with subjective (NASA-TLX) and physiological mental workload measures (heart rate variability and eye-tracking). The results show that task type impacts the performance, task duration, and mental workload. Although the physiological workload measures showed significant impact, the parameters standard deviation of R-R intervals and LF/HF ratio ...


3d Visualization And Interactive Image Manipulation For Surgical Planning In Robot-Assisted Surgery, Mohammadreza Maddah Jan 2018

3d Visualization And Interactive Image Manipulation For Surgical Planning In Robot-Assisted Surgery, Mohammadreza Maddah

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Robot-assisted surgery, or "robotic" surgery, has been developed to address the difficulties with the traditional laparoscopic surgery. The da Vinci (Intuitive Surgical, CA and USA) is one of the FDA-approved surgical robotic system which is widely used in the case of abdominal surgeries like hysterectomy and cholecystectomy. The technology includes a system of master and slave tele-manipulators that enhances manipulation precision. However, inadequate guidelines and lack of a human-machine interface system for planning the ports on the abdomen surface are some of the main issues with robotic surgery. Unreachable target and mid-surgery collisions between robotic arms are the major problems ...


Threats And Mitigation Of Ddos Cyberattacks Against The U.S. Power Grid Via Ev Charging, Glenn Sean Morrison Jan 2018

Threats And Mitigation Of Ddos Cyberattacks Against The U.S. Power Grid Via Ev Charging, Glenn Sean Morrison

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Cars are an ever changing and integral part of modern society. Two of the biggest changes in vehicles today are their heavy integration with wireless communication and the push toward battery powered Electric Vehicles (EV). EV and EV charging stations have become a part of the Internet of Things (IoT). While this connectedness increases the convenience and functionality of the vehicles and charging stations, it also opens them up to a wide range of cyber threats. This thesis examines the potential threats against the EV charging ecosystem through a historical analysis of past cyberattacks and identified vulnerabilities. As EV charging ...


Coupling Computational Fluid Dynamics Analysis And Optimization Techniques For Scramjet Engine Design, Nathan T. Mcgillivray Jan 2018

Coupling Computational Fluid Dynamics Analysis And Optimization Techniques For Scramjet Engine Design, Nathan T. Mcgillivray

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Various aspects of hypersonic vehicles are being rapidly explored for improved functionality. One of the main areas of consideration is the fueling of a Supersonic Combusting Ramjet (scramjet) engine. Using Computational Fluid Dynamics (CFD), computer simulations can be performed to analyze the flow physics of a scramjet. In this research, an optimization code, Dakota, is integrated with the CFD to optimize a set of parameters to maximum thrust. In this study, the fuel injection and combustion is replaced with heat sources. This simplification greatly reduces the computational requirements. Additionally, the 3D geometry is reduced to an axisymmetric 2D geometry because ...