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Full-Text Articles in Engineering

Virtual Reality And Analysis Framework For Studying Different Layout Designs, Madison Glines Jan 2019

Virtual Reality And Analysis Framework For Studying Different Layout Designs, Madison Glines

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This thesis describes the tools for studying different design prototypes. The goal was to develop effective tools to study these designs using a data-driven approach. “Proof of concept” experiments were conducted, in which participants were allowed to interact with a virtual environment depicting different designs as data pertaining to their virtual location and orientation was recorded for later analysis. The designs included “flat” store racks, as opposed to racks with more varied shapes, as well as “curved” racks. Focus of the design studies was to assist in identifying optimal locations for different product types. The automated data collection mechanisms required …

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Securing Modern Cyberspace Using A Multi-Faceted Approach, Yu Li Jan 2019

Securing Modern Cyberspace Using A Multi-Faceted Approach, Yu Li

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Security has become one of the most significant concerns for our cyberspace. Securing the cyberspace, however, becomes increasingly challenging. This can be attributed to the rapidly growing diversities and complexity of the modern cyberspace. Specifically, it is not any more dominated by connected personal computers (PCs); instead, it is greatly characterized by cyber-physical systems (CPS), embedded systems, dynamic services, and human-computer interactions. Securing modern cyberspace therefore calls for a multi-faceted approach capable of systematically integrating these emerging characteristics. This dissertation presents our novel and significant solutions towards this direction. Specifically, we have devised automated, systematic security solutions to three critical …

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Monitoring Cerebral Functional Response Using Scmos-Based High Density Near Infrared Spectroscopic Imaging, Dharminder Singh Langri Jan 2019

Monitoring Cerebral Functional Response Using Scmos-Based High Density Near Infrared Spectroscopic Imaging, Dharminder Singh Langri

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Neurovascular coupling is an important concept that indicates the direct link between neuronal electrical firing with the vascular hemodynamic changes. Functional Near Infrared Spectroscopy (fNIRS) can measure changes in cerebral vascular parameters of oxy-hemoglobin and deoxyhemoglobin concentrations and thus can provide neuronal activity through neurovascular coupling. Currently many commercial fNIRS devices are available, but they are limited by the number of channels (usually having only 8 detectors), which can limit the sensitivity, contrast, and resolution of imaging. High-density imaging can improve sensitivity, contrast, and resolution by providing many measurements and averaging the signals originating from the target cerebral focus area …

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Mixed Signal Detection, Estimation, And Modulation Classification, Yang Qu Jan 2019

Mixed Signal Detection, Estimation, And Modulation Classification, Yang Qu

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Signal detection, parameter estimation and modulation classification are widely applied to many areas and plays a very important role in civilian and military, such as bio-science, criminal psychology, communication engineering, radar system, electronic warfare and so on. In the civilian field, with the increasing number of wireless electronic devices and higher transmission data rate demand, the problem of spectrum congestion becomes more and more highlighted and urgent. In recent years, wireless industry has shown great interest in Cognitive Radio (CR) and Dynamic Spectrum Access (DSA) network, whose primary function is to use limited frequency bands to transmit own signals without …

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Islands Of Fitness Compact Genetic Algorithm For Rapid In-Flight Control Learning In A Flapping-Wing Micro Air Vehicle: A Search Space Reduction Approach, Kayleigh E. Duncan Jan 2019

Islands Of Fitness Compact Genetic Algorithm For Rapid In-Flight Control Learning In A Flapping-Wing Micro Air Vehicle: A Search Space Reduction Approach, Kayleigh E. Duncan

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On-going effective control of insect-scale Flapping-Wing Micro Air Vehicles could be significantly advantaged by active in-flight control adaptation. Previous work demonstrated that in simulated vehicles with wing membrane damage, in-flight recovery of effective vehicle attitude and vehicle position control precision via use of an in-flight adaptive learning oscillator was possible. Most recent approaches to this problem employ an island-of-fitness compact genetic algorithm (ICGA) for oscillator learning. The work presented provides the details of a domain specific search space reduction approach implemented with existing ICGA and its effect on the in-flight learning time. Further, it will be demonstrated that the proposed …

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Immersive Rehearsal In A Simulated Environment (Irise), Cassandra Clouse Jan 2019

Immersive Rehearsal In A Simulated Environment (Irise), Cassandra Clouse

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Recent advancements in virtual environment (VE) technology and the growth of VE use in treating and training individuals are opening up new possibilities for rehearsal in safe and rich environments. Research has shown that VEs can be used to treat those with Post Traumatic Stress Disorder (PTSD), but very little research has been done to suggest good guidelines for creating an effective environment. This research was conducted to help inform the design of systems that let veterans rehearse potentially stressful experiences in a safe environment before having to physically step into that environment. We investigated responses to specific design components …

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Blended Wing Design Considerations For A Next Generation Commercial Aircraft, Jay Abhilash Vora Jan 2019

Blended Wing Design Considerations For A Next Generation Commercial Aircraft, Jay Abhilash Vora

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The current aircraft design has not changed significantly in the last few decades. Growing environmental concerns and fuel prices are driving manufacturers to develop unconventional but efficient aircraft configurations. The blended wing body (BWB) configuration provides an alternate and more efficient means of subsonic travel. The BWB aircraft replaces the traditional wings and fuselage with hybrid wing shape where the fuselage and wings have integrated. Major aircraft manufacturers are researching the BWB concept incorporating electric propulsion for civil transport use. In this research a 300 passenger BWB aircraft aerodynamic shape is designed. This aircraft is used to assess the aerodynamic …

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Differential Microrna Expression In Barrett's Esophagus Correlates With Regulation Of Posterior Homeotic Genes, Reilly June Clark Jan 2019

Differential Microrna Expression In Barrett's Esophagus Correlates With Regulation Of Posterior Homeotic Genes, Reilly June Clark

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Barrett’s Esophagus (BE) is characterized by the appearance of an intestinal-like epithelium in the distal esophagus. The molecular mechanisms behind BE development are unknown. BE is often preceded by Gastroesophageal Reflux Disease (GERD) and predisposes patients to esophageal adenocarcinoma (EAC). Due to the high mortality rate associated with EAC, BE patients are continuously monitored through upper endoscopy with biopsy for progression to low grade dysplasia (LGD), high grade dysplasia, and EAC. This monitoring technique poses numerous risks, so alternative surveillance and diagnostic techniques for BE pathogenesis are continually studied. microRNA biomarkers in BE pathogenesis may provide alternative means of diagnosis …

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Power/Thermal Interaction Within An Adaptive Turbine Engine, Andrew K. Desomma Jan 2019

Power/Thermal Interaction Within An Adaptive Turbine Engine, Andrew K. Desomma

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Usually power take off (PTO) with a two-spool turbofan engine has been accomplished via the high pressure (HP) shaft and bleed air from the high-pressure compressor (HPC). The PTO is used to run various aircraft components such as generators and hydraulic pumps, which also produce waste heat. To better understand the coupled transient nature of balancing engine thrust, power take off and thermal management, a transient variable cycle three stream turbofan engine model has been developed to investigate the integrated behavior. The model incorporates many dynamic features including a third-stream heat exchanger as a heat sink for thermal management and …

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Towards Data And Model Confidentiality In Outsourced Machine Learning, Sagar Sharma Jan 2019

Towards Data And Model Confidentiality In Outsourced Machine Learning, Sagar Sharma

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With massive data collections and needs for building powerful predictive models, data owners may choose to outsource storage and expensive machine learning computations to public cloud providers (Cloud). Data owners may choose cloud outsourcing due to the lack of in-house storage and computation resources or the expertise of building models. Similarly, users, who subscribe to specialized services such as movie streaming and social networking, voluntarily upload their data to the service providers' site for storage, analytics, and better services. The service provider, in turn, may also choose to benefit from ubiquitous cloud computing. However, outsourcing to a public cloud provider …

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Hierarchical Carbon Structures With Vertically- Aligned Nanotube Carpets For Oil-Water Separation Under Different Conditions, Kimia Kiaei Jan 2019

Hierarchical Carbon Structures With Vertically- Aligned Nanotube Carpets For Oil-Water Separation Under Different Conditions, Kimia Kiaei

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The primary purpose of this study is to investigate the role of surface nano-structuring in fluid separation. It is hypothesized that hierarchical carbon structures consisting of aligned carbon nanotube arrays strongly adhered to the surface of porous carbon solids such as fabric and foam, can be used for separation of polar and non-polar fluids by selective wettability of one fluid and rejection of another. The vertically-aligned carbon nanotube arrays, as synthesized, possess super hydrophobicity demonstrated by high water contact angle on their surfaces. On the other hand, they are incredibly oleophilic, showing a high affinity to adsorb oil. These properties …

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Abusive And Hate Speech Tweets Detection With Text Generation, Abhishek Nalamothu Jan 2019

Abusive And Hate Speech Tweets Detection With Text Generation, Abhishek Nalamothu

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According to a Pew Research study, 41% of Americans have personally experienced online harassment and two-thirds of Americans have witnessed harassment in 2017. Hence, online harassment detection is vital for securing and sustaining the popularity and viability of online social networks. Machine learning techniques play a crucial role in automatic harassment detection. One of the challenges of using supervised approaches is training data imbalance. Existing text generation techniques can help augment the training data, but they are still inadequate and ineffective. This research explores the role of domain-specific knowledge to complement the limited training data available for training a text …

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Stability Analysis Of Leg Configurations For Bipedal Running, Nitin Jaiswal Jan 2019

Stability Analysis Of Leg Configurations For Bipedal Running, Nitin Jaiswal

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A legged robot with three-segmented limbs is used to study the effects of leg compliance originating from the joint level on the stability of hopping in place and running. The three-segments allow each leg to be kinematically configured an infinite number ways that satisfy the desired landing condition parameters, total leg length and angle. These two parameters along with the amount of energy thrust during stance determine the motion of the system during a single stride. The goal of this work is to explore the potential values for the leg parameters of three-segment leg, that provide additional stability when compared …

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Configurable Frequency And Voltage Three Phase Power Supply, Donald Danko Jan 2019

Configurable Frequency And Voltage Three Phase Power Supply, Donald Danko

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The student's employer is in need of a three phase power supply which can supply a 400Hz signal at +/- 28V at 2A. The input to the power supply is +24VDC at an unspecified current. The student's solution is a configurable frequency and voltage power supply. The student chose to utilize a full bridge DC to DC converter topology. A microcontroller was used for supplying pulse width modulated waveforms, performing analog to digital conversions, and controlling a digital to analog converter. The circuit was modeled using Matlab and tested after being manufactured to confirm proper functionality. The configurable three phase …

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Llvm-Ir Based Decompilation, Ilsoo Jeon Jan 2019

Llvm-Ir Based Decompilation, Ilsoo Jeon

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Decompilation is a process of transforming an executable program into a source-like high-level language code, which plays an important role in malware analysis, and vulnerability detection. In this thesis, we design and implement the middle end of a decompiler framework, focusing on Low Level Language properties reduction using the optimization techniques, propagation and elimination. An open-source software tool, dagger, is used to translate binary code to LLVM (Low Level Virtual Machine) Intermediate Representation code. We perform data flow analysis and control flow analysis on the LLVM format code to generate high-level code using a Functional Programming Langauge (FPL), Haskell. The …

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Multi-Sensor Approach To Determine The Effect Of Geometry On Microstructure In Additive Manufacturing, Joseph R. Walker Jan 2019

Multi-Sensor Approach To Determine The Effect Of Geometry On Microstructure In Additive Manufacturing, Joseph R. Walker

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Laser powder bed fusion (LPBF) is an additive manufacturing technique used for making complex parts through a layer-by-layer process with fine feature resolution. However, the layer-by-layer process, with complex scanning patterns within each layer, introduces variability in thermal behavior leading to inconsistent microstructure and defects. The in- situ process monitoring approach in this work uses sensors including a high-speed visible camera, thermal camera, and spectrometer to evaluate each location in the LPBF process. Each sensor focuses on a different process phenomenon such as the melt pool or thermal behavior. An experimental study, using metallographic analysis and collection of sensor data, …

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Speech Enabled Navigation In Virtual Environments, Raksha Rajashekar Jan 2019

Speech Enabled Navigation In Virtual Environments, Raksha Rajashekar

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Navigating in a Virtual Environment with traditional input devices such as mouse, joysticks and keyboards provide limited maneuverability and is also time consuming. While working in a virtual environment, changing parameters to obtain the desired visualization requires time to achieve by manually entering parameter values in an algorithm to test outcomes. The following thesis presents an alternate user interface to reduce user efforts, while navigating within the Virtual Environment. The user interface is an Android application which is designed to accommodate spoken commands. This Speech Enabled User Interface termed as the Speech Navigation Application (SNA), provides the user with an …

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Aerodynamics Of Fan Blade Blending, Clint J. Knape Jan 2019

Aerodynamics Of Fan Blade Blending, Clint J. Knape

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Blending is a method of fan and compressor blade repair. The goal of the blending process is to remove stress concentration points such as cracks and nicks along the leading, trailing, or tip edges of the blade. The stressed areas are typically removed by grinding or cropping away the surrounding material. For integrally bladed rotor (IBR) disks, repairing a damaged blade is much more economical than replacing the entire disk. However, the change in shape of the blade will change the local aerodynamics and result in mistuning, both structurally and aerodynamically. In a worst case scenario, the change in the …

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Analytical And Experimental Investigation Of Time-Variant Acceleration Fields, Justin A. Williams Jan 2019

Analytical And Experimental Investigation Of Time-Variant Acceleration Fields, Justin A. Williams

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Devices expected to operate in elevated or non-standard acceleration fields are often tested in similar conditions prior to deployment. Typically these tests only simulate steady-state acceleration fields in one direction. However, real acceleration fields often vary both directionally and temporally. Designing experiments to produce these conditions requires careful forethought and analysis in order to understand the emergent acceleration components that result from the methodology. An experiment was designed and executed on a horizontal centrifuge in which the radial acceleration varied sinusoidally between -10 < a_r < 10 g. Negative acceleration was achieved by rotating the test article relative to the radial acceleration vector using a servo motor. A model was developed that predicted the acceleration field at every point along the test article. The model provided important information such as the acceleration magnitude and direction anywhere on the test device at any point in time. This model was then used to optimize the velocity profile of the servo motor to minimize experimental artifacts.

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Adaptive Identification Of Classification Decision Boundary Of Turbine Blade Mode Shape Under Geometric Uncertainty, Ian M. Boyd Jan 2019

Adaptive Identification Of Classification Decision Boundary Of Turbine Blade Mode Shape Under Geometric Uncertainty, Ian M. Boyd

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Integrally Bladed Rotors (IBR) of aircraft turbine engines suffer from fluctuations in the dynamic response that occurs due to blade to blade geometric deviations. The Stochastic Approach for Blade and Rotor Emulation (SABRE) framework has been used to enable a probabilistic study of mistuned blades in which a reduced order modeling technique is applied in conjunction with sets of surrogate models, called emulators, to make predictions of mistuned mode shapes. SABRE has proven useful for non-switching mode shapes. However, switching mode shapes have non-stationary or discontinuous response surfaces which reduce the accuracy of the surrogate models used in SABRE. To …

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Kbot: Knowledge-Enabled Personalized Chatbot For Self-Management Of Asthma In Pediatric Population, Dipesh Kadariya Jan 2019

Kbot: Knowledge-Enabled Personalized Chatbot For Self-Management Of Asthma In Pediatric Population, Dipesh Kadariya

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Asthma, chronic pulmonary disease, is one of the major health issues in the United States. Given its chronic nature, the demand for continuous monitoring of patient’s adherence to the medication care plan, assessment of their environment triggers, and management of asthma control level can be challenging in traditional clinical settings and taxing on clinical professionals. A shift from a reactive to a proactive asthma care can improve health outcomes and reduce expenses. On the technology spectrum, smart conversational systems and Internet-of-Things (IoTs) are rapidly gaining popularity in the healthcare industry. By leveraging such technological prevalence, it is feasible to design …

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Conditional Dilated Attention Tracking Model - C-Datm, Tyler Clayton Highlander Jan 2019

Conditional Dilated Attention Tracking Model - C-Datm, Tyler Clayton Highlander

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Current commercial tracking systems do not process images fast enough to perform target-tracking in real- time. State-of-the-art methods use entire scenes to locate objects frame-by-frame and are commonly computationally expensive because they use image convolutions. Alternatively, attention mechanisms track more efficiently by mimicking human optical cognitive interaction to only process small portions of an image. Thus, in this work we use an attention-based approach to create a model called C-DATM (Conditional Dilated Attention tracking Model) that learns to compare target features in a sequence of image-frames using dilated convolutions. The C-DATM is tested using the Modified National Institute of Standards …

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Leveraging Schema Information For Improved Knowledge Graph Navigation, Rama Someswar Chittella Jan 2019

Leveraging Schema Information For Improved Knowledge Graph Navigation, Rama Someswar Chittella

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Over the years, the semantic web has emerged as a new generation of the world wide web featuring advanced technologies and research contributions. It has revolutionized the usage of information by allowing users to capture and publish machine-understandable data and expedite methods such as ontologies to perform the same. These ontologies help in the formal representation of a specified domain and foster comprehensive machine understanding. Although, the engineering of ontologies and usage of logic have been an integral part of the web semantics, new areas of research such as the semantic web search, linking and usage of open data on …

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Deposition Of Nanoparticles Or Thin Films Via Magnetron Sputtering Towards Graphene Surface Functionalization And Device Fabrication, Bridget Jul Larson Jan 2019

Deposition Of Nanoparticles Or Thin Films Via Magnetron Sputtering Towards Graphene Surface Functionalization And Device Fabrication, Bridget Jul Larson

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Graphene, a 2-dimensional single layer of carbon, has high carrier mobility, strength and electrical conductivity. Due to the absence of a band gap and chemical reactivity, pristine graphene has less competitiveness in semiconductors and sensors. Functionalizing graphene is imperative in the development of advanced applications. Among various wet chemical or physical vapor deposition, magnetron sputtering is cost-effective, minimum maintenance, user-friendly, and can be used to rapidly deposit nano-particulates or thin films with less contaminations on any substrates surface. This study is to investigate the morphology evolution of the deposited films using magnetron sputtering and to find appropriate conditions for nanoparticulate …

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Static Evaluation Of Type Inference And Propagation On Global Variables With Varying Context, Ivan Frasure Jan 2019

Static Evaluation Of Type Inference And Propagation On Global Variables With Varying Context, Ivan Frasure

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Software reverse engineering (SRE) is a broad field with motivations ranging from verifying or documenting gordian source code files to understanding and reimplementing binary object files and executables. SRE of binaries is exceptionally compelling and challenging due to large amounts of information that can be lost in the compilation progress. A central area in SRE is type inference. Type inference is built around a fundamental step in understanding the behavior of a binary, recovering the types of data in the program. Type inference has many unique techniques in both static and dynamic type inference systems that have been implemented in …

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Using Cfd To Improve Off-Design Throughflow Analysis, Troy J. Lanchman Jan 2019

Using Cfd To Improve Off-Design Throughflow Analysis, Troy J. Lanchman

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In turbomachinery design, complex internal flows give rise to significant losses and blockage whose effects are difficult to properly analyze without detailed computational fluid dynamics (CFD) methods or experiments. In a typical design method, CFD is used in conjunction with simpler throughflow or cascade codes to hasten the process. However, the lesser physical accuracy of the design codes demands the inclusion of models to improve the accuracy of the throughflow codes. This thesis aims to use CFD data to generate improved loss and blockage models for a 2D compressor throughflow code by matching throughflow data to CFD data using optimizations. …

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The Development Of The Human-Automation Behavioral Interaction Task (Habit) Analysis Framework, Isabelle Catherine Baird Jan 2019

The Development Of The Human-Automation Behavioral Interaction Task (Habit) Analysis Framework, Isabelle Catherine Baird

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Complex systems involve the collaboration of automated agents and goal-oriented human operators in a dynamic environment, and dynamic environments required dynamic automation. The implementation of automation fundamentally changes the nature of the cognitive demands by means of changing the role of the human operator. The augmentation of operator situation awareness has become a major design objective in the development of human-automated systems. Extensive literature identified the out-of-the-loop performance problem as a human-automation interaction challenge. This thesis presents the Human-Automation Behavioral Interaction Task (HABIT) Analysis, as a novel approach to assessing human-automation interaction challenges, such as out-of-the-loop consequences. The novel framework …

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Anticipation In Dynamic Environments: Deciding What To Monitor, Zohreh A. Dannenhauer Jan 2019

Anticipation In Dynamic Environments: Deciding What To Monitor, Zohreh A. Dannenhauer

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In dynamic environments, external changes may occur that may affect planning decisions and goal choices. We claim that an intelligent agent should actively watch for what can go wrong and anticipate changes in the environment that allows the changing of its plan or changing of a given goal. In this thesis, we focus on the relationship between perception, act, interpretation, and planning. We claim that these components are not independent and need to interact with each other to help the agent succeed in achieving its goals and plans. If newly encountered world information affects the plan, the agent adapts to …

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Agent-Based Simulation Of Artificial-Intelligence-Assisted Transfer Of Care, Paul B. Stone Jan 2019

Agent-Based Simulation Of Artificial-Intelligence-Assisted Transfer Of Care, Paul B. Stone

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This study demonstrates the application of Agent-Based Simulation as a potential training aid for Transfer of Care (ToC) between EMS and a hospital triage department. The specific aim was to develop a simulation to increase the efficiency and accountability of information communication during ToC to test the suitability of Agent-Based Simulation to address training requirements in complex, health provision settings. This paper focuses on the design of the training simulation, including the development of individual agents within the simulation through the user interface elements and the evaluation and verification of the prototype simulator. The primary objective is for the simulation …

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Digital Instantaneous Frequency Measurement Receiver For Fine Frequency And High Sensitivity, Bilal Khudhur Abdulhammed Abdulhamed Jan 2019

Digital Instantaneous Frequency Measurement Receiver For Fine Frequency And High Sensitivity, Bilal Khudhur Abdulhammed Abdulhamed

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Wideband technology has been applied to many wide bandwidth applications when there is a need to send much different information in a short time from one point and received from another point in high precision and accuracy. A wideband receiver reports a signal without tuning if the signal is within the input bandwidth. The analog Instantaneous Frequency Measurement (IFM) receiver has been used for decades to cover a very wide input bandwidth and report one accurate frequency on a short pulse at a time. The digital IFM use a high sampling rate ADC to operate in a wide bandwidth, Hilbert …

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