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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, …

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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 …

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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 on …

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Failure Analysis Of Philos Plate Construct Used For Pantalar Arthrodesis Paper I—Analysis Of The Plate, Jason Ina, Madhurima Vallentyne, Farah Hamandi, Kathleen Shugart, Michael A. Boin, Richard T. Laughlin, Tarun Goswami Jan 2018

Failure Analysis Of Philos Plate Construct Used For Pantalar Arthrodesis Paper I—Analysis Of The Plate, Jason Ina, Madhurima Vallentyne, Farah Hamandi, Kathleen Shugart, Michael A. Boin, Richard T. Laughlin, Tarun Goswami

Orthopaedic Surgery Faculty Publications

The failure of a proximal humerus internal locking system (PHILOS) used in a pantalar arthrodesis was investigated in this paper. PHILOS constructs are hybrids using locking and non-locking screws. Both the plate and the screws used in the fusion were obtained for analysis. However, only the plate failure analysis is reported in this paper. The implant had failed in several pieces. Optical and scanning electron microscopic analyses were performed to characterize the failure mode(s) and fracture surface. The chemical composition and mechanical properties of the plate were determined and compared to controlling specifications to manufacture the devices. We found that …

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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 …

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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 …

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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 …

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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 …

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Leveraging 3d Models For Sar-Based Navigation In Gps-Denied Environments, Zachary A. Reid Jan 2018

Leveraging 3d Models For Sar-Based Navigation In Gps-Denied Environments, Zachary A. Reid

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This thesis considers the use of synthetic aperture radar (SAR) to provide absolute platform position information in scenarios where GPS signals may be degraded, jammed, or spoofed. Two algorithms are presented, and both leverage known 3D ground structure in an area of interest, e.g. provided by LIDAR data, to provide georeferenced position information to airborne SAR platforms. The first approach is based on the wide-aperture layover properties of elevated reflectors, while the second approach is based on correlating backprojected imagery with digital elevation imagery. Both of these approaches constitute the system we have designated: SARNAV. Building on 3D backprojection, localization …

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Follower Commitment: The Impact Of Authentic Leadership's Positivity And Justice On Presenteeism, Caroline Antonia Drakeley Jan 2018

Follower Commitment: The Impact Of Authentic Leadership's Positivity And Justice On Presenteeism, Caroline Antonia Drakeley

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Leadership behaviors are associated with organizational commitment for a unique niche of individuals - those who produce less work while in the workplace due to health-related problems, such as anxiety, stress, or depression. New research shows followers' perceptions of leaders' positive support and organizational justice (procedural and distributive) are significantly positively associated with followers' perceived organizational commitment. This quantitative correlational study explored the relationship between followers' perceptions of leadership support, leadership procedural justice, and leadership distributive justice, as well as their own perceptions of their emotional stability, and organizational commitment using the authentic leadership framework. Further research using multiple linear …

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Microstructural Characterization Of LensTm Ti-6al-4v: Investigating The Effects Of Process Variables Across Multiple Deposit Geometries, Laura Christine Davidson Jan 2018

Microstructural Characterization Of LensTm Ti-6al-4v: Investigating The Effects Of Process Variables Across Multiple Deposit Geometries, Laura Christine Davidson

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Laser based additive manufacturing of Ti-6Al-4V components is under consideration for aerospace applications. The mechanical properties of the finished components depend on their microstructure. Process mapping compares process variables such as heat source power, heat source travel speed, material feed rate, part preheat temperature and feature geometry to process outcomes such as microstructure, melt pool geometry and residual stresses. In this work, the microstructure of two-dimensional pads, multilayer pads, thin walls, and structural components at the steady state location was observed. A method for measuring β grain widths that allows for the calculation of standard deviations, confidence intervals, and variances …

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An Autonomous Intelligent Robotic Wheelchair To Assist People In Need: Standing-Up, Turning-Around And Sitting-Down, Iosif Papadakis Ktistakis Jan 2018

An Autonomous Intelligent Robotic Wheelchair To Assist People In Need: Standing-Up, Turning-Around And Sitting-Down, Iosif Papadakis Ktistakis

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The world’s ageing population has significantly increased over the last decades, which will result in one of the most significant transformations of the twenty-first century. As people age, they become more vulnerable to diseases and their health may need constant monitoring. At the same time, the number of people who have some kind of disability is also increasing. These people with disabilities may need daily assistance and monitoring of their health condition that is provided by specialists (health providers) at a high cost. A possible solution to the aforementioned problem comes from the assistive and intelligent robotics research area. The …

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Interactive Visualization Of Search Results Of Large Document Sets, James D. Anderson Jan 2018

Interactive Visualization Of Search Results Of Large Document Sets, James D. Anderson

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When presented with many search results, finding information or patterns within the data poses a challenge. This thesis presents the design, implementation and evaluation of a visualization enabling users to browse through voluminous information and comprehend the data. Implemented with the JavaScript library Data Driven Documents (D3), the visualization represents the search as clusters of similar documents grouped into bubbles with the contents depicted as word-clouds. Highly interactive features such as touch gestures and intuitive menu actions allow for expeditious exploration of the search results. Other features include drag-and-drop functionality for articles among bubbles, merging nodes, and refining the search …

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Switching Neural Network Systems For Nonlinear Tracking, Manoj Ghimire Jan 2018

Switching Neural Network Systems For Nonlinear Tracking, Manoj Ghimire

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In this thesis, we consider the problem of tracking in complex nonlinear dynamical systems. While the Kalman filter is known to be the mean-squared error optimal tracker under linear dynamics and linear measurements, more sophisticated models and algorithms are required for complex dynamics. Here, we consider switching systems where the dynamical properties vary (''switch modes") over time. For example, the dynamics of a vehicle may switch as it transitions from interstate to urban conditions, human speech dynamics switch as speakers change, and stock market dynamics switch with discrete news events. In this work, we use mode-dependent neural networks to capture …

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Overwhelming The Saa System Of Delivery Uavs By Drone Swarming, Barry Lynn Pfaff Jan 2018

Overwhelming The Saa System Of Delivery Uavs By Drone Swarming, Barry Lynn Pfaff

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As the Internet continues to replace the brick-and-mortar store as the main place for purchasing goods, web-based companies are looking for ways to reduce the cost of delivering those goods. The use of Unmanned Aerial Vehicles, or UAVs, is one delivery method that is increasingly being used. These UAVs can be programmed with delivery routes and destinations and can complete the job while requiring limited intervention from human controllers. Sense and Avoidance (SAA) systems have recently been incorporated into these UAVs so that they can detect objects in their flight path, reroute the UAV accordingly and operate even more autonomously. …

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Fully Transparent Computer Vision Framework For Ship Detection And Tracking In Satellite Imagery, Jason T. Gottweis Jan 2018

Fully Transparent Computer Vision Framework For Ship Detection And Tracking In Satellite Imagery, Jason T. Gottweis

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Tracking of ships in satellite imagery is a challenging problem in remote sensing since it requires both object detection and object recognition. Most of the resources available only cover one of these problems and are often filled with machine learning techniques which are costly to train. Additionally, the techniques covered in these resources are often difficult to replicate or may be hard to combine with other solutions to get a full tracking algorithm. The proposed framework offers a transparent and efficient alternative to machine learning approaches and includes preprocessing, detection, and recognition needed for tracking. All components of the framework …

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Augment The Multi-Modal Interaction Capabilities Of Hololens Through Networked Sensory Devices, Subhadra Tummalapally Jan 2018

Augment The Multi-Modal Interaction Capabilities Of Hololens Through Networked Sensory Devices, Subhadra Tummalapally

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Augmented Reality (AR) places virtual contents along with real objects to enhance user perception in the physical environment. It is a technology that has shown great potential in many industries such as medicine, education and transportation. AR devices, such as Microsoft HoloLens, come with multi-modal interaction capabilities, such as voice, gesture and gaze, to support intuitive and reliable human-computer interactions. However, HoloLens gesture support is limited to simple gestures like tap, bloom and hold, it stops short to support meaningful interaction through full hand gesture and motion tracking, which may be critical in field operations of various industry practices in …

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Wideband Doa And Parameter Estimation Of Chirp Sources Using Dcft And Compressive Sensing, Luay A. Al Irkhis Jan 2018

Wideband Doa And Parameter Estimation Of Chirp Sources Using Dcft And Compressive Sensing, Luay A. Al Irkhis

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Direction of Arrival (DoA) estimation of chirp sources has many applications in radar, sonar and medical imaging. This work considers DoA and parameter estimation of wide- band chirp sources by the use of Discrete Chirp Fourier Transform (DCFT), its Compres- sive Sensing formulation (CS-DCFT) and Distributed CS. DCFT is similar to traditional Discrete Fourier Transform (DFT) but with chirp ba- sis and two-dimensional search over chirp rate and chirp frequency. For chirp parame- ters estimation, the proposed Compressive Sensing (CS) formulation uses the parametric DCFT basis to achieve superior estimator performance in polynomial time using Orthog- onal Matching Pursuit (OMP) …

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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 agreed with …

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Explaining Nuclear Rollback: Examining The Cessation Of Nuclear Weaponization In Argentina And Brazil From 1964 - 1994, Billy Michael Douglas Jan 2018

Explaining Nuclear Rollback: Examining The Cessation Of Nuclear Weaponization In Argentina And Brazil From 1964 - 1994, Billy Michael Douglas

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Seventy years after the first use of nuclear weapons in World War II, the proliferation of these apocalyptic munitions remains a key policy issue on the international stage. The available literature on nuclear proliferation suggests a strong correlation between the threat of rival a state seeking nuclear weapons and a state's own decision to pursue its own nuclear weapons. Regional rivals Argentina and Brazil both initiated nuclear weapons programs and were also developing nuclear delivery systems; however, these countries were able to step out of this dyadic proliferation spiral and renounced their nuclear weapons programs. Often assumed a success of …

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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 precautions …

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A Model For Seasonal Dynamic Networks, Jace D. Robinson Jan 2018

A Model For Seasonal Dynamic Networks, Jace D. Robinson

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Sociotechnological and geospatial processes exhibit time varying structure that make insight discovery challenging. This paper presents statistical model of systems with seasonal dynamics, modeled as a dynamic network, to address this challenge. It assumes the probability of edge formations depend on a type assigned to incident nodes and the current time. Time dependencies are modeled by unique seasonal processes. The model is studied on several synthetic and real datasets. Superior fidelity of this model on seasonal datasets compared to existing network models, while being able to remain equally accurate for networks with randomly changing structure, is shown. The model is …

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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 …

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Chinese Satellite Diplomacy: China's Strategic Weapon For Soft And Hard Power Gains, Nicholas Jackman Jan 2018

Chinese Satellite Diplomacy: China's Strategic Weapon For Soft And Hard Power Gains, Nicholas Jackman

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China signed its first turn-key communication satellite contract with Nigeria in 2004. The contract stipulated that China would design, build, integrate, launch, and complete in-orbit checkout for the Nigcomsat-1 communication satellite and then transfer control over to Nigeria. By 2018, China had contracted and launched another six communication satellites for various foreign customers. The customers, who are foreign governments, are geographically dispersed throughout South America, Europe, Africa, and Asia. The satellite sales have occurred during China's unprecedented economic growth, a time in which China has been granted additional foreign policy options as its power increases relative to others. This thesis …

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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 …

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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, …

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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 of …

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A Multi-Formal Languages Collaborative Scheme For Complex Human Activity Recognition And Behavioral Patterns Extraction, Anargyros Angeleas Jan 2018

A Multi-Formal Languages Collaborative Scheme For Complex Human Activity Recognition And Behavioral Patterns Extraction, Anargyros Angeleas

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Human Activity Recognition is an actively researched domain for the past few decades, and is one of the most eminent applications of today. It is already part of our life, but due to high level of uncertainty and challenges of human detection, we have only application specific solutions. Thus, the problem being very demanding and still remains unsolved. Within this PhD we delve into the problem, and approach it from a variety of viewpoints. At start, we present and evaluate different architectures and frameworks for activity recognition. Henceforward, the focal point of our attention is automatic human activity recognition. We …

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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 and LITFSI. The impacts of the LAGP on …

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Comparison Of Cyber Network Defense Visual Displays, Christen Elizabeth Lopez Sushereba Jan 2018

Comparison Of Cyber Network Defense Visual Displays, Christen Elizabeth Lopez Sushereba

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This work describes an Ecological Interface Design (EID) comparison of five displays (Alphanumeric, 2D and 3D Aggregate, Radial, and Treemap) on accuracy and latency performance for simple cyber network data analysis tasks. Twenty students from the Computer Science and Engineering Department at Wright State University participated for compensation. Questions (n = 12) ranged from global to specific aspects of the data and required two types of responses: numerical estimates and binary visual judgments. EID principles of attunement and specificity (Bennett & Flach, 2011) guided the interpretation of results. Participants answered faster when the display's visual forms (vertical extent, area, or …

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