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Theses and Dissertations

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Full-Text Articles in Computer Engineering

A Hierarchical Architectural Framework For Securing Unmanned Aerial Systems, Matthew Leccadito Jan 2017

A Hierarchical Architectural Framework For Securing Unmanned Aerial Systems, Matthew Leccadito

Theses and Dissertations

Unmanned Aerial Systems (UAS) are becoming more widely used in the new era of evolving technology; increasing performance while decreasing size, weight, and cost. A UAS equipped with a Flight Control System (FCS) that can be used to fly semi- or fully-autonomous is a prime example of a Cyber Physical and Safety Critical system. Current Cyber-Physical defenses against malicious attacks are structured around security standards for best practices involving the development of protocols and the digital software implementation. Thus far, few attempts have been made to embed security into the architecture of the system considering security as a holistic problem. …


Improving The Performance And Time-Predictability Of Gpus, Yijie Huangfu Jan 2017

Improving The Performance And Time-Predictability Of Gpus, Yijie Huangfu

Theses and Dissertations

Graphic Processing Units (GPUs) are originally mainly designed to accelerate graphic applications. Now the capability of GPUs to accelerate applications that can be parallelized into a massive number of threads makes GPUs the ideal accelerator for boosting the performance of such kind of general-purpose applications. Meanwhile it is also very promising to apply GPUs to embedded and real-time applications as well, where high throughput and intensive computation are also needed.

However, due to the different architecture and programming model of GPUs, how to fully utilize the advanced architectural features of GPUs to boost the performance and how to analyze the …


Feature Based Object Tracking: A Probabilistic Approach, Kaleb Smith Dec 2016

Feature Based Object Tracking: A Probabilistic Approach, Kaleb Smith

Theses and Dissertations

Video analysis is a rich research topic, due to the wide spectrum of applications such as surveillance, activity recognition, security, and event detection. One of the important challenges in video analysis is object tracking, which provides the ability to determine the exact location of an object of interest within each frame. Many challenges affect the efficiency of a tracking algorithm such as scene illumination change, occlusion, scaling change and determining a search window from which to track object(s). We present an integrated probabilistic model for object track- ing, that combines implicit dynamic shape representations and probabilistic object modeling. We demonstrate …


Evaluation Of User Perceived Qoe In Mobile Systems Using Social Media Analytics, Ahmed Yaseen Mjhool Dec 2016

Evaluation Of User Perceived Qoe In Mobile Systems Using Social Media Analytics, Ahmed Yaseen Mjhool

Theses and Dissertations

In mobile system environments, the quality perceived by users is inconstant and reliant on many factors such as cellular network, data connection, cost, coverage area, etc. Even though Quality of Service (QoS) management is enabled in most modern telecommunication systems, it does not guarantee the actual user’s perceived Quality of Experience (QoE) level. Many cellular networks rely on engineering test research, such as drive testing or smart mobile applications, to collect the required parameters in order to provide better service quality to users. However, this approach does not always yield customer satisfaction. Hence, user opinions should be considered. These opinions …


Fuzzy Expert Systems: A More Human-Based Approach For Sensorial Evaluation Of Coffee-Bean Attributes To Derive Quality Scoring, Javier A. Livio Nov 2016

Fuzzy Expert Systems: A More Human-Based Approach For Sensorial Evaluation Of Coffee-Bean Attributes To Derive Quality Scoring, Javier A. Livio

Theses and Dissertations

In the coffee industry, "cupping" is the process of sensorial evaluations of coffee beans, also known as Sample Evaluation. This process is done for three major reasons: to determine the actual sensory differences between coffee samples, to describe the flavors of the samples, and to determine preference of product. In totality, cupping targets the measurement of the coffee's quality related to fragrance, taste, and appearance which are expressed with a final numerical score. When cupping, the expert judge writes down the individual components' scores (fragrance, aftertaste, acidity, body, etc.) and ranks their intensities for reference. Despite the fact the cuppers …


Aes Encryption Algorithm Using Arm Trustzone Technology, Chia-Che Lee Nov 2016

Aes Encryption Algorithm Using Arm Trustzone Technology, Chia-Che Lee

Theses and Dissertations

With the huge impact of IoT devices, the security needs are becoming more important than what it had before. Since embedded systems have limited resources, the traditional security solutions are not quite fitting to IoTs because the huge power consumption and resource. ARM TrustZone Technology is a hardware based security feature using in ARM-based devices with minimum resource taken. TrustZone provides a critical environment to isolate security and non-security tasks within Normal and Security World. Both worlds can be a General Purpose Operating System (GPOS) or a Real-Time Operating System (RTOS) depending on designer has needs, and running simultaneously on …


Real-Time Monitoring Of Sand And Dust Storm Winds Using Wireless Sensor Technology, Hana Mohammed Mujlid Sep 2016

Real-Time Monitoring Of Sand And Dust Storm Winds Using Wireless Sensor Technology, Hana Mohammed Mujlid

Theses and Dissertations

This dissertation proposes an empirical model for prediction of the radio path loss in Wireless Sensor Networks (WSNs). The model applies to WSNs that are deployed in environments with dust and sand storms. It is developed as a result of statistical analysis of the measured data collected during dust and sand storms. The measured data were obtained at 2.4GHz and for different levels of the storm severity. For the purpose of data collection a custom measurement system based on Xbee air interface was developed. The proposed model shows a very good agreement with the measured data. It is also demonstrated …


3d Object Recognition For A Portable Robotic Navigation Aid, Xiangfei Qian Jul 2016

3d Object Recognition For A Portable Robotic Navigation Aid, Xiangfei Qian

Theses and Dissertations

The objective of this dissertation is to develop a 3D object recognition method for a portable robotic navigation aid, called “Smart Cane” (SC), for the visually impaired. The SC is a computer-vision-enhanced white cane that uses a single 3D time-of-flight camera for navigation in an indoor environment. To achieve the navigation function, the SC should be able to perform SLAM (Simultaneous Localization And Mapping) and object recognition. In this dissertation, we focus on object recognition. Firstly, a method, named Normal-Coherence-Check RANSAC (RANdom Sample Consensus), is proposed to perform robust and fast plane extraction. Secondly, a 3D object recognition method based …


Visibility-Based Pursuit-Evasion In The Plane, Nicholas Michael Stiffler Jun 2016

Visibility-Based Pursuit-Evasion In The Plane, Nicholas Michael Stiffler

Theses and Dissertations

As technological advances further increase the amount of memory and computing power available to mobile robots, we are seeing an unprecedented explosion in the utilization of deployable robots for various tasks. The speed at which robots begin to enter various domains is largely dependent on the availability of robust and efficient algorithms that are capable of solving the complex planning problems inherent to the given domain. One such domain which is experiencing unprecedented growth in recent years requires a robot to detect and/or track a mobile agent or group of agents.

In these scenarios, there are typically two players with …


Preprocessing Techniques To Support Event Detection Data Fusion On Social Media Data, Brandon T. Davis Jun 2016

Preprocessing Techniques To Support Event Detection Data Fusion On Social Media Data, Brandon T. Davis

Theses and Dissertations

This thesis focuses on collection and preprocessing of streaming social media feeds for metadata as well as the visual and textual information. Today, news media has been the main source of immediate news events, large and small. However, the information conveyed on these news sources is delayed due to the lack of proximity and general knowledge of the event. Such news have started relying on social media sources for initial knowledge of these events. Previous works focused on captured textual data from social media as a data source to detect events. This preprocessing framework postures to facilitate the data fusion …


An Arithmetic-Based Deterministic Centroid Initialization Method For The K-Means Clustering Algorithm, Matthew Michael Mayo May 2016

An Arithmetic-Based Deterministic Centroid Initialization Method For The K-Means Clustering Algorithm, Matthew Michael Mayo

Theses and Dissertations

One of the greatest challenges in k-means clustering is positioning the initial cluster centers, or centroids, as close to optimal as possible, and doing so in an amount of time deemed reasonable. Traditional fc-means utilizes a randomization process for initializing these centroids, and poor initialization can lead to increased numbers of required clustering iterations to reach convergence, and a greater overall runtime. This research proposes a simple, arithmetic-based deterministic centroid initialization method which is much faster than randomized initialization. Preliminary experiments suggest that this collection of methods, referred to herein as the sharding centroid initialization algorithm family, often outperforms random …


An Exploration Of Rule Clustering In Cellular Automata Rule Spaces, Jordon Huffman May 2016

An Exploration Of Rule Clustering In Cellular Automata Rule Spaces, Jordon Huffman

Theses and Dissertations

The study of complex systems examines the global behavior of a system and how the individual parts of the system affect that behavior [1]. The study of complex systems spans across many fields of science like biology, physics, engineering, and computer science. One area of complex systems that has not been fully explored is cellular automata. Since its discovery by John von Neumann, there have been no consistent ways of categorizing similarities between cellular automata rules or collecting similar rules for observation. This thesis introduces an approach to identifying clusters of similar rules and extracting rules from that cluster. Several …


Hardware Acceleration For Real Time Atmospheric Turbulence Compensation, Nikhileswar Badri Apr 2016

Hardware Acceleration For Real Time Atmospheric Turbulence Compensation, Nikhileswar Badri

Theses and Dissertations

Atmospheric turbulence compensation techniques are used to apply filters and to remove noise from the information, such as images. In mission control applications, the processing is required in real time. This thesis focuses on understanding the process and developing architecture for hardware acceleration on the FPGA. Error calculation is a computational extensive component and is a continuous research area to correctly and efficiently measure it in real-time for data processing. The Error is used as a metric to compute the corrected data, such as an image pixel representing the phase, color and intensity to perform image processing. The thesis discusses …


Google Speech Recognition Using Embedded System, Anita Devi Apr 2016

Google Speech Recognition Using Embedded System, Anita Devi

Theses and Dissertations

This thesis will describe the theoretical background and implementation details of Google Speech Recognition using embedded system. AM37x Evaluation Board developed by Texas Instrument is used as a test bed. All major applications of Google Speech Recognition are covered in this thesis. Also, Evaluation of Google Speech API based on standard dataset is also part of the thesis.

Each implementation details are included with the theoretical background and pre-requisite details:

  • Overview of the background of Automatic Speech Recognition Technology.
  • Overview of Google Speech Recognition.
  • Overview of AM37x Evaluation Module.
  • Drivers and Android OS upgradation details.
  • Installation of Google pre-requisite Apps …


Exposing Inter-Virtual Machine Networking Traffic To External Applications, Charles E. Byrd Mar 2016

Exposing Inter-Virtual Machine Networking Traffic To External Applications, Charles E. Byrd

Theses and Dissertations

Virtualization is a powerful and fast growing technology that is widely accepted throughout the computing industry. The Department of Defense has moved its focus to virtualization and looks to take advantage of virtualized hardware, software, and networks. Virtual environments provide many benefits but create both administrative and security challenges. The challenge of monitoring virtual networks is having visibility of inter-virtual machine (VM) traffic that is passed within a single virtual host. This thesis attempts to gain visibility and evaluate performance of inter-VM traffic in a virtual environment. Separate virtual networks are produced using VMWare ESXi and Citrix XenServer platforms. The …


Towards Automated Aerial Refueling: Real Time Position Estimation With Stereo Vision, Bradley D. Denby Mar 2016

Towards Automated Aerial Refueling: Real Time Position Estimation With Stereo Vision, Bradley D. Denby

Theses and Dissertations

Aerial refueling is essential to the United States Air Force (USAF) core mission of rapid global mobility. However, in-flight refueling is not available to remotely piloted aircraft (RPA) or unmanned aerial systems (UAS). As reliance on drones for intelligence, surveillance, and reconnaissance (ISR) and other USAF core missions grows, the ability to automate aerial refueling for such systems becomes increasingly critical. New refueling platforms include sensors that could be used to estimate the relative position of an approaching aircraft. Relative position estimation is a key component to solving the automated aerial refueling (AAR) problem. Analysis of data from a one-seventh …


Airborne Directional Networking: Topology Control Protocol Design, Barry C. Geise Mar 2016

Airborne Directional Networking: Topology Control Protocol Design, Barry C. Geise

Theses and Dissertations

This research identifies and evaluates the impact of several architectural design choices in relation to airborne networking in contested environments related to autonomous topology control. Using simulation, we evaluate topology reconfiguration effectiveness using classical performance metrics for different point-to-point communication architectures. Our attention is focused on the design choices which have the greatest impact on reliability, scalability, and performance. In this work, we discuss the impact of several practical considerations of airborne networking in contested environments related to autonomous topology control modeling. Using simulation, we derive multiple classical performance metrics to evaluate topology reconfiguration effectiveness for different point-to-point communication architecture …


A Practical Wireless Exploitation Framework For Z-Wave Networks, Joseph L. Hall Mar 2016

A Practical Wireless Exploitation Framework For Z-Wave Networks, Joseph L. Hall

Theses and Dissertations

Wireless Sensor Networks (WSN) are a growing subset of the emerging Internet of Things (IoT). WSNs reduce the cost of deployment over wired alternatives; consequently, use is increasing in home automation, critical infrastructure, smart metering, and security solutions. Few published works evaluate the security of proprietary WSN protocols due to the lack of low-cost and effective research tools. One such protocol is ITU-T G.9959-based Z-Wave, which maintains wide acceptance within the IoT market. This research utilizes an open source toolset, presented herein, called EZ-Wave to identify methods for exploiting Z-Wave devices and networks using Software-Defined Radios (SDR). Herein, techniques enabling …


Dynamic Network Security Control Using Software Defined Networking, Michael C. Todd Mar 2016

Dynamic Network Security Control Using Software Defined Networking, Michael C. Todd

Theses and Dissertations

This thesis develops and implements a process to rapidly respond to host level security events using a host agent, Software Defined Networking and OpenFlow updates, role based flow classes, and Advanced Messaging Queuing Protocol to automatically update configuration of switching devices and block malicious traffic. Results show flow table updates are made for all tested levels in less than 5.27 milliseconds and event completion time increased with treatment level as expected. As the number of events increases from 1,000 to 50,000, the design scales logarithmically caused mainly by message delivery time. Event processing throughput is limited primarily by the message …


A Service Oriented Architecture Approach For Global Positioning System Quality Of Service Monitoring, Stuart A. Everson Mar 2016

A Service Oriented Architecture Approach For Global Positioning System Quality Of Service Monitoring, Stuart A. Everson

Theses and Dissertations

This research focuses on the development of a Service Oriented Architecture (SOA) for monitoring the Global Positioning System (GPS) Standard Positioning Service (SPS) in near real time utilizing a Mobile Crowd Sensing (MCS) technique. A unique approach to developing the MCS SOA was developed that utilized both the Depart- ment of Defense Architecture Framework (DoDAF) and the SOA Modeling Language (SoaML) guidance. The combination of these two frameworks resulted in generation of all the architecture products required to evaluate the SOA through the use of Model Based System Engineering (MBSE) techniques. Ultimately this research provides a feasibility analysis for utilization …


Improving Understandability And Uncertainty Modeling Of Data Using Fuzzy Logic Systems, Dumidu S. Wijayasekara Jan 2016

Improving Understandability And Uncertainty Modeling Of Data Using Fuzzy Logic Systems, Dumidu S. Wijayasekara

Theses and Dissertations

The need for automation, optimality and efficiency has made modern day control and monitoring systems extremely complex and data abundant. However, the complexity of the systems and the abundance of raw data has reduced the understandability and interpretability of data which results in a reduced state awareness of the system. Furthermore, different levels of uncertainty introduced by sensors and actuators make interpreting and accurately manipulating systems difficult. Classical mathematical methods lack the capability to capture human knowledge and increase understandability while modeling such uncertainty.

Fuzzy Logic has been shown to alleviate both these problems by introducing logic based on vague …


Revealing Malicious Contents Hidden In The Internet, Muhammad Nazmus Sakib Jan 2016

Revealing Malicious Contents Hidden In The Internet, Muhammad Nazmus Sakib

Theses and Dissertations

In this age of ubiquitous communication in which we can stay constantly connected with the rest of the world, for most of the part, we have to be grateful for one particular invention - the Internet. But as the popularity of Internet connectivity grows, it has become a very dangerous place where objects of malicious content and intent can be hidden in plain sight. In this dissertation, we investigate different ways to detect and capture these malicious contents hidden in the Internet. First, we propose an automated system that mimics high-risk browsing activities such as clicking on suspicious online ads, …


Mitigating Interference During Virtual Machine Live Migration Through Storage Offloading, Morgan S. Stuart Jan 2016

Mitigating Interference During Virtual Machine Live Migration Through Storage Offloading, Morgan S. Stuart

Theses and Dissertations

Today's cloud landscape has evolved computing infrastructure into a dynamic, high utilization, service-oriented paradigm. This shift has enabled the commoditization of large-scale storage and distributed computation, allowing engineers to tackle previously untenable problems without large upfront investment. A key enabler of flexibility in the cloud is the ability to transfer running virtual machines across subnets or even datacenters using live migration. However, live migration can be a costly process, one that has the potential to interfere with other applications not involved with the migration. This work investigates storage interference through experimentation with real-world systems and well-established benchmarks. In order to …


A Hierarchical Framework For Phylogenetic And Ancestral Genome Reconstruction On Whole Genome Data, Lingxi Zhou Jan 2016

A Hierarchical Framework For Phylogenetic And Ancestral Genome Reconstruction On Whole Genome Data, Lingxi Zhou

Theses and Dissertations

Gene order gets evolved under events such as rearrangements, duplications, and losses, which can change both the order and content along the genome, through the long history of genome evolution. Recently, the accumulation of genomic sequences provides researchers with the chance to handle long-standing problems about the phylogenies, or evolutionary histories, of sets of species, and ancestral genomic content and orders. Over the past few years, such problems have been proven so interesting that a large number of algorithms have been proposed in the attempt to resolve them, following different standards. The work presented in this dissertation focuses on algorithms …


Positioning Commuters And Shoppers Through Sensing And Correlation, Rufeng Meng Jan 2016

Positioning Commuters And Shoppers Through Sensing And Correlation, Rufeng Meng

Theses and Dissertations

Positioning is a basic and important need in many scenarios of human daily activities. With position information, multifarious services could be vitalized to benefit all kinds of users, from individuals to organizations. Through positioning, people are able to obtain not only geo-location but also time related information. By aggregating position information from individuals, organizations could derive statistical knowledge about group behaviors, such as traffic, business, event, etc.

Although enormous effort has been invested in positioning related academic and industrial work, there are still many holes to be filled. This dissertation proposes solutions to address the need of positioning in people’s …


Regular Expression Synthesis For Blast Two-Hit Filtering, Jordan Bradshaw Jan 2016

Regular Expression Synthesis For Blast Two-Hit Filtering, Jordan Bradshaw

Theses and Dissertations

Genomic databases are exhibiting a growth rate that is outpacing Moore's Law, which has made database search algorithms a popular application for use on emerging processor technologies. NCBI BLAST is the standard tool for performing searches against these databases, which operates by transforming each database query into a filter that is subsequently applied to the database. This requires a database scan for every query, fundamentally limiting its performance by I/O bandwidth. In this dissertation we present a functionally-equivalent variation on the NCBI BLAST algorithm that maps more suitably to an FPGA implementation. This variation of the algorithm attempts to reduce …


Efficient Partitioning And Allocation Of Data For Workflow Compositions, Annamaria Victoria Kish Jan 2016

Efficient Partitioning And Allocation Of Data For Workflow Compositions, Annamaria Victoria Kish

Theses and Dissertations

Our aim is to provide efficient partitioning and allocation of data for web service compositions. Web service compositions are represented as partial order database transactions. We accommodate a variety of transaction types, such as read-only and write-oriented transactions, to support workloads in cloud environments. We introduce an approach that partitions and allocates small units of data, called micropartitions, to multiple database nodes. Each database node stores only the data needed to support a specific workload. Transactions are routed directly to the appropriate data nodes. Our approach guarantees serializability and efficient execution.

In Phase 1, we cluster transactions based on data …


Hydro-Geological Flow Analysis Using Hidden Markov Models, Chandrahas Raj Venkat Gurram Jan 2016

Hydro-Geological Flow Analysis Using Hidden Markov Models, Chandrahas Raj Venkat Gurram

Theses and Dissertations

Hidden Markov Models a class of statistical models used in various disciplines for understanding speech, finding different types of genes responsible for cancer and much more. In this thesis, Hidden Markov Models are used to obtain hidden states that can correlate the flow changes in the Wakulla Spring Cave. Sensors installed in the tunnels of Wakulla Spring Cave have recorded huge correlated changes in the water flows at numerous tunnels. Assuming the correlated flow changes are a consequence of system being in a set of discrete states, a Hidden Markov Model is calculated. This model comprising all the sensors installed …


In-Shoe Plantar Pressure System To Investigate Ground Reaction Force Using Android Platform, Ahmed A. Mostfa Jan 2016

In-Shoe Plantar Pressure System To Investigate Ground Reaction Force Using Android Platform, Ahmed A. Mostfa

Theses and Dissertations

Human footwear is not yet designed to optimally relieve pressure on the heel of the foot. Proper foot pressure assessment requires personal training and measurements by specialized machinery. This research aims to investigate and hypothesize about Preferred Transition Speed (PTS) and to classify the gait phase of explicit variances in walking patterns between different subjects. An in-shoe wearable pressure system using Android application was developed to investigate walking patterns and collect data on Activities of Daily Living (ADL). In-shoe circuitry used Flexi-Force A201 sensors placed at three major areas: heel contact, 1st metatarsal, and 5th metatarsal with a PIC16F688 microcontroller …


Direct L2 Support Vector Machine, Ljiljana Zigic Jan 2016

Direct L2 Support Vector Machine, Ljiljana Zigic

Theses and Dissertations

This dissertation introduces a novel model for solving the L2 support vector machine dubbed Direct L2 Support Vector Machine (DL2 SVM). DL2 SVM represents a new classification model that transforms the SVM's underlying quadratic programming problem into a system of linear equations with nonnegativity constraints. The devised system of linear equations has a symmetric positive definite matrix and a solution vector has to be nonnegative.

Furthermore, this dissertation introduces a novel algorithm dubbed Non-Negative Iterative Single Data Algorithm (NN ISDA) which solves the underlying DL2 SVM's constrained system of equations. This solver shows significant speedup compared to several other state-of-the-art …