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Theses and Dissertations

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Full-Text Articles in Computer Engineering

Design And Simulation Of An Intelligent Self-Adaptive System For A Smart Home, Basman M. Hasan Alhafidh Jul 2018

Design And Simulation Of An Intelligent Self-Adaptive System For A Smart Home, Basman M. Hasan Alhafidh

Theses and Dissertations

Home automation and control systems as basic elements of smart cities have played a key role in the development of our homes environments . They have a wide range of applications in many fields at home such as security and monitoring, healthcare, energy, and entertainment applications. The improvement of humans’ living standards make people keep trying to delegate many of their needs to a home automation system. Such a system has been built with capabilities of predicting what the user intends to do in smart home environment. However, there are many issues that need more investigation and solutions, such as: …


Robust Pose Estimation Of A Robotic Navigation Aid For The Visually Impaired By Multimodal Data Fusion, He Zhang Jun 2018

Robust Pose Estimation Of A Robotic Navigation Aid For The Visually Impaired By Multimodal Data Fusion, He Zhang

Theses and Dissertations

For a visually impaired individual, it is a challenging task for him/her to plan and follow a path towards the destination. This task is referred to as wayfinding. In this paper, the functions of wayfinding are defined as localization (aka pose estimation) in an indoor environment and finding a way to get to the destination by using the location information. To address this issue, vision-based navigation systems that use a camera for pose estimation have been intensively studied. Several vision-based robotic navigation aids (RNAs) for the visually impaired have been developed. However, these RNAs are not reliable enough to assist …


Web Aplikacioni Për Menaxhimin E Eventeve Në Kosovë, Fatlind Dautaj Jun 2018

Web Aplikacioni Për Menaxhimin E Eventeve Në Kosovë, Fatlind Dautaj

Theses and Dissertations

Një nga problemet më aktuale në Kosove është informimi rreth eventeve dhe vendeve turistike. Bazuar në këtë fakt, mungesa e informacioneve rreth eventeve dhe vendeve turistike ka bëre që të mos zhvillohet mjaftueshëm turizimi në Kosovë. Meqenëse informimi rreth turizmit deri me tani është bërë përmes broshurave, te cilat nuk mundë të permbanin mjaftushëm informacione, të cilat kishin ndikim jo të mire edhe për ambientin dhe që nuk ishin mjaft te sigurta se informacioni nga ato do të mundë të arrihej te përsonat e interesuar për event.Mirëpo me zhvillimin e këtij web aplikacioni atëherë gjithqka është lehtësuar pasi që informimi …


Digital Automatic Speech Recognition Using Kaldi, Sarah Habeeb Alyousefi May 2018

Digital Automatic Speech Recognition Using Kaldi, Sarah Habeeb Alyousefi

Theses and Dissertations

The Automatic speech recognition (ASR) system is one of most important technologies that used for human-machine interaction. The main goal of the ASR system is to recognize different natural languages that are spoken by humans. The difficulties of these recognition systems depend on many factors, such as noises, variability of the speakers, and problems of continuous speech. For that reason, many researchers and foundations have designed different kinds of licensed toolkits and software that are specialized in building speech recognition systems, including , Julius, Sphinx-4, RWTH ASR, and HTK toolkits. In this thesis, Kaldi toolkit, which is one of the …


Automatic Speech Recognition Adaptation For Various Noise Levels, Azhar Sabah Abdulaziz May 2018

Automatic Speech Recognition Adaptation For Various Noise Levels, Azhar Sabah Abdulaziz

Theses and Dissertations

The automatic speech recognition (ASR) is a set of complicated algorithms that convert the intended spoken utterance into a textual form. Acoustic features, which are extracted from the speech signal, are matched against a trained network of linguistic and acoustic models. The ASR performance is degraded significantly when the ambient noise is different than that of the training data. Many approaches have been introduced to address this problem with various degrees of complexity and improvement rates. The general pattern of solving this issue lies in three categories: empowering features, train a general acoustic model and transform models to match noisy …


Pollen Grains Recognition Based On Computer Vision Methods, Amar Idrees Daood May 2018

Pollen Grains Recognition Based On Computer Vision Methods, Amar Idrees Daood

Theses and Dissertations

The classification of pollen grains is a main task in many disciplines including ecology, forensic sciences, allergy control, and oil exploration. In these application areas, visual inspection is the common method used for classifying pollen. However, recognition by visual inspection consumes much time and effort. Even though some level of automation exists, the automatic recognition of pollen grains remains an open problem. Current pollen-classification solutions rely on measurements of visual cues such as contour or texture. However, these features do not capture the visual complexity of information needed for discriminating among various species of pollen, especially when both a large-scale …


Speech Emotion Recognition Using Connectionist Models In A Tandem System, Mary Najafi May 2018

Speech Emotion Recognition Using Connectionist Models In A Tandem System, Mary Najafi

Theses and Dissertations

This article presents a tandem Speech Emotion Recognition (SER) system by which 8 archetypal emotions can be differentiated based upon two different types of acoustic features as inputs to Artificial Neural Network (ANN) models. The two types of features that are fed into the classifiers reveal the degree of excitement and pleasentness of speech. The author has implied the time-based characteristics of speech in the feature extraction method by monitoring the trend of local features through time. Thus, two global features are proposed that are derived from Teager Energy Operator (TEO)-based (T EOg) and spectral features, Mel-Frequency Cepstral Coeffcients (MF …


Estimating Defensive Cyber Operator Decision Confidence, Markus M. Borneman Mar 2018

Estimating Defensive Cyber Operator Decision Confidence, Markus M. Borneman

Theses and Dissertations

As technology continues to advance the domain of cyber defense, signature and heuristic detection mechanisms continue to require human operators to make judgements about the correctness of machine decisions. Human cyber defense operators rely on their experience, expertise, and understanding of network security, when conducting cyber-based investigations, in order to detect and respond to cyber alerts. Ever growing quantities of cyber alerts and network traffic, coupled with systemic manpower issues, mean no one has the time to review or change decisions made by operators. Since these cyber alert decisions ultimately do not get reviewed again, an inaccurate decision could cause …


Assessing The Competing Characteristics Of Privacy And Safety Within Vehicular Ad Hoc Networks, Jacob W. Connors Mar 2018

Assessing The Competing Characteristics Of Privacy And Safety Within Vehicular Ad Hoc Networks, Jacob W. Connors

Theses and Dissertations

The introduction of Vehicle-to-Vehicle (V2V) communication has the promise of decreasing vehicle collisions, congestion, and emissions. However, this technology places safety and privacy at odds; an increase of safety applications will likely result in the decrease of consumer privacy. The National Highway Traffic Safety Administration (NHTSA) has proposed the Security Credential Management System (SCMS) as the back end infrastructure for maintaining, distributing, and revoking vehicle certificates attached to every Basic Safety Message (BSM). This Public Key Infrastructure (PKI) scheme is designed around the philosophy of maintaining user privacy through the separation of functions to prevent any one subcomponent from identifying …


Assured Android Execution Environments, Brandon P. Froberg Mar 2018

Assured Android Execution Environments, Brandon P. Froberg

Theses and Dissertations

Current cybersecurity best practices, techniques, tactics and procedures are insufficient to ensure the protection of Android systems. Software tools leveraging formal methods use mathematical means to assure both a design and implementation for a system and these methods can be used to provide security assurances. The goal of this research is to determine methods of assuring isolation when executing Android software in a contained environment. Specifically, this research demonstrates security properties relevant to Android software containers can be formally captured and validated, and that an implementation can be formally verified to satisfy a corresponding specification. A three-stage methodology called "The …


Digital Forensics Event Graph Reconstruction, Daniel J. Schelkoph Mar 2018

Digital Forensics Event Graph Reconstruction, Daniel J. Schelkoph

Theses and Dissertations

Ontological data representation and data normalization can provide a structured way to correlate digital artifacts. This can reduce the amount of data that a forensics examiner needs to process in order to understand the sequence of events that happened on the system. However, ontology processing suffers from large disk consumption and a high computational cost. This paper presents Property Graph Event Reconstruction (PGER), a novel data normalization and event correlation system that leverages a native graph database to improve the speed of queries common in ontological data. PGER reduces the processing time of event correlation grammars and maintains accuracy over …


Cyber Data Anomaly Detection Using Autoencoder Neural Networks, Spencer A. Butt Mar 2018

Cyber Data Anomaly Detection Using Autoencoder Neural Networks, Spencer A. Butt

Theses and Dissertations

The Department of Defense requires a secure presence in the cyber domain to successfully execute its stated mission of deterring war and protecting the security of the United States. With potentially millions of logged network events occurring on defended networks daily, a limited staff of cyber analysts require the capability to identify novel network actions for security adjudication. The detection methodology proposed uses an autoencoder neural network optimized via design of experiments for the identification of anomalous network events. Once trained, each logged network event is analyzed by the neural network and assigned an outlier score. The network events with …


Cybersecurity Assessment And Mitigation Stochastic Model, Matthew W. Davis Mar 2018

Cybersecurity Assessment And Mitigation Stochastic Model, Matthew W. Davis

Theses and Dissertations

With numerous cybersecurity incidents and vulnerability concerns in an increasingly contested cyber warfighting environment, the Department of Defense (DoD) has mandated cybersecurity assessment and authorization of all major weapon systems (MWS) before their use. In response to this direction, the Air Force Life Cycle Management Center (AFLCMC) created the Platform Information Technology Assessment and Authorization (PIT A&A) Process. Modeled after the NIST Risk Management Framework (RMF), this process applies a risk-based approach to cybersecurity with the goal of identifying risks and mitigating vulnerabilities in MWS. Within this work, a stochastic model of the PIT A&A Process is presented with an …


Progressive Network Deployment, Performance, And Control With Software-Defined Networking, Daniel J. Casey Mar 2018

Progressive Network Deployment, Performance, And Control With Software-Defined Networking, Daniel J. Casey

Theses and Dissertations

The inflexible nature of traditional computer networks has led to tightly-integrated systems that are inherently difficult to manage and secure. New designs move low-level network control into software creating software-defined networks (SDN). Augmenting an existing network with these enhancements can be expensive and complex. This research investigates solutions to these problems. It is hypothesized that an add-on device, or "shim" could be used to make a traditional switch behave as an OpenFlow SDN switch while maintaining reasonable performance. A design prototype is found to cause approximately 1.5% reduction in throughput for one ow and less than double increase in latency, …


Evaluation Of Resiliency In A Wide-Area Backup Protection System Via Model Checking, Kolby H. Elliot Mar 2018

Evaluation Of Resiliency In A Wide-Area Backup Protection System Via Model Checking, Kolby H. Elliot

Theses and Dissertations

Modern civilization relies heavily on having access to reliable power sources. Recent history has shown that present day protection systems are not adequate. Numerous backup protection (BP) systems have been proposed to mitigate the impact of primary protection system failures. Many of these novel BP systems rely on autonomous agents communicating via wide-area networks. These systems are highly complex and their control logic is based on distributed computing. Model checking has been shown to be a powerful tool in analyzing the behavior of distributed systems. In this research the model checker SPIN is used to evaluate the resiliency of an …


Bandwidth Analysis Of A Tightly-Packed Crossed-Dipole Array For Satellite Communications, Lawrence J. Lee Mar 2018

Bandwidth Analysis Of A Tightly-Packed Crossed-Dipole Array For Satellite Communications, Lawrence J. Lee

Theses and Dissertations

A bandwidth analysis of a tightly-packed crossed-dipole array antenna is presented in this thesis. A parametric study is described which varies the element spacing in the array and the resulting change in the terminal impedances is reported. The increased mutual coupling seen by the elements as a result of smaller element spacings is shown to minimize the variation in the value of the elements terminal currents across a 0.3 GHz to 3.0 GHz frequency range. This small variation in current translates into a minimal variation in the terminal impedances for a fixed excitation voltage. This is shown to be an …


Assessment Of Structure From Motion For Reconnaissance Augmentation And Bandwidth Usage Reduction, Jonathan B. Roeber Mar 2018

Assessment Of Structure From Motion For Reconnaissance Augmentation And Bandwidth Usage Reduction, Jonathan B. Roeber

Theses and Dissertations

Modern militaries rely upon remote image sensors for real-time intelligence. A typical remote system consists of an unmanned aerial vehicle, or UAV, with an attached camera. A video stream is sent from the UAV, through a bandwidth-constrained satellite connection, to an intelligence processing unit. In this research, an upgrade to this method of collection is proposed. A set of synthetic images of a scene captured by a UAV in a virtual environment is sent to a pipeline of computer vision algorithms, collectively known as Structure from Motion. The output of Structure from Motion, a three-dimensional model, is then assessed in …


Market Basket Analysis With Shortened Web Link Click Data, James C. Gallagher Mar 2018

Market Basket Analysis With Shortened Web Link Click Data, James C. Gallagher

Theses and Dissertations

Market research is an indispensable part of an organization's ability to understand market dynamics in an area. Over the past 20 years data collection and analysis through Knowledge Discovery through Databases (KDD) has arisen to supplement the traditional methods of surveys and focus groups. Market Basket Analysis is an area of KDD that identifies associations between commonly purchased items. As social media use has grown, link shortening companies help users share links in a constrained space environment and, in exchange, collect data about each user when a link is clicked. This research applies market basket analysis techniques with graph mining …


An Analysis Of Multi-Domain Command And Control And The Development Of Software Solutions Through Devops Toolsets And Practices, Mason R. Bruza Mar 2018

An Analysis Of Multi-Domain Command And Control And The Development Of Software Solutions Through Devops Toolsets And Practices, Mason R. Bruza

Theses and Dissertations

Multi-Domain Command and Control (MDC2) is the exercise of command and control over forces in multiple operational domains (namely air, land, sea, space, and cyberspace) in order to produce synergistic effects in the battlespace, and enhancing this capability has become a major focus area for the United States Air Force (USAF). In order to meet demands for MDC2 software, solutions need to be acquired and/or developed in a timely manner, information technology infrastructure needs to be adaptable to new software requirements, and user feedback needs to drive iterative updates to fielded software. In commercial organizations, agile software development methodologies and …


Quality Of Service Impacts Of A Moving Target Defense With Software-Defined Networking, Samuel A. Mayer Mar 2018

Quality Of Service Impacts Of A Moving Target Defense With Software-Defined Networking, Samuel A. Mayer

Theses and Dissertations

An analysis of the impact a defensive network technique implemented with software-defined networking has upon quality of service experienced by legitimate users. The research validates previous work conducted at AFIT to verify claims of defensive efficacy and then tests network protocols in common use (FTP, HTTP, IMAP, POP, RTP, SMTP, and SSH) on a network that uses this technique. Metrics that indicate the performance of the protocols under test are reported with respect to data gathered in a control network. The conclusions of these experiments enable network engineers to determine if this defensive technique is appropriate for the quality of …


Internet Of Things For A Smart Transportation System, Ahmed Yahya Awad Mar 2018

Internet Of Things For A Smart Transportation System, Ahmed Yahya Awad

Theses and Dissertations

Today, school buses transport millions of students to and from schools. Therefore, the safety of school students is still a hot topic and the most imperative issue. The evolution of wireless location-based services has created consumer requests for the availability of global positioning systems (GPS) in urban and indoor environments. Nowadays, there is a requirement to improve a monitoring system for the school bus, that monitors its location and speed. This work investigates two different ways to track the vehicle through ordinary GPS or Assisted-GPS (A-GPS). A-GPS improves startup performance (time-to-first-fix (TTFF)), of a GPS satellite-based positioning system in the …


Sentiment Analysis Of Twitter Data, Evan L. Munson Mar 2018

Sentiment Analysis Of Twitter Data, Evan L. Munson

Theses and Dissertations

The rapid expansion and acceptance of social media has opened doors into users’ opinions and perceptions that were never as accessible as they are with today's prevalence of mobile technology. Harvested data, analyzed for opinions and sentiment can provide powerful insight into a population. This research utilizes Twitter data due to its widespread global use, in order to examine the sentiment associated with tweets. An approach utilizing Twitter #hashtags and Latent Dirichlet Allocation topic modeling were utilized to differentiate between tweet topics. A lexicographical dictionary was then utilized to classify sentiment. This method provides a framework for an analyst to …


Blockchain Scalability And Security, Tuyet Duong Jan 2018

Blockchain Scalability And Security, Tuyet Duong

Theses and Dissertations

Cryptocurrencies like Bitcoin have proven to be a phenomenal success. The underlying techniques hold huge promise to change the future of financial transactions, and eventually the way people and companies compute, collaborate, and interact. At the same time, the current Bitcoin-like proof-of-work based blockchain systems are facing many challenges. In more detail, a huge amount of energy/electricity is needed for maintaining the Bitcoin blockchain. In addition, their security holds if the majority of the computing power is under the control of honest players. However, this assumption has been seriously challenged recently and Bitcoin-like systems will fail when this assumption is …


On The Security And Quality Of Wireless Communications In Outdoor Mobile Environment, Sharaf J. Malebary Jan 2018

On The Security And Quality Of Wireless Communications In Outdoor Mobile Environment, Sharaf J. Malebary

Theses and Dissertations

The rapid advancement in wireless technology along with their low cost and ease of deployment have been attracting researchers academically and commercially. Researchers from private and public sectors are investing into enhancing the reliability, robustness, and security of radio frequency (RF) communications to accommodate the demand and enhance lifestyle. RF base communications -by nature- are slower and more exposed to attacks than a wired base (LAN). Deploying such networks in various cutting-edge mobile platforms (e.g. VANET, IoT, Autonomous robots) adds new challenges that impact the quality directly. Moreover, adopting such networks in public outdoor areas make them vulnerable to various …


Bytecode-Based Multiple Condition Coverage: An Initial Investigation, Srujana Bollina Jan 2018

Bytecode-Based Multiple Condition Coverage: An Initial Investigation, Srujana Bollina

Theses and Dissertations

Masking occurs when one condition prevents another condition from influencing the output of a Boolean expression. Logic-based adequacy criteria such as Multiple Condition Coverage (MCC) are designed to overcome masking at the within-expression level, but can offer no guarantees about masking in subsequent expressions. As a result, a Boolean expression written as a single complex statement will yield test cases that are more likely to overcome masking than when the expression is written as series of simple statements. Many approaches to automated analysis and test case generation for Java systems operate not on the source code representation of code, but …


Ontology-Guided Pre-Release Inference Disruption, Mark Stephen Daniels Jan 2018

Ontology-Guided Pre-Release Inference Disruption, Mark Stephen Daniels

Theses and Dissertations

We investigate privacy violations occurring when non-confidential patient data is combined with medical domain ontologies to disclose a patient’s protected health information (PHI). We propose a framework that detects privacy violations and eliminates undesired inferences. Our inference channel removal process is based on controlling the release of the data items that lead to undesired inferences. These data items are either blocked from release or generalized to eliminate the disclosure of the PHI. We show that our method is sound and complete. Soundness means the only inference paths generated logically follow from released data and corresponding domain knowledge. Completeness means we …


The Design, Development, And Evaluation Of A Usable And Privacy-Enhanced Telepresence Interface For Older Adults, Xian Wu Jan 2018

The Design, Development, And Evaluation Of A Usable And Privacy-Enhanced Telepresence Interface For Older Adults, Xian Wu

Theses and Dissertations

Maintaining health and wellness while aging-in-place independently is crucial for older adults. Telepresence technology can be potentially beneficial for this target population to stay socially connected. However, this technology is not specifically designed for older adults. For this target population to adopt such technology successfully, it is important to ensure that they do not experience usability barriers. This research uses HCI/HRI concepts and technology design principles for older adults to design, develop and test telepresence user interfaces (UI). This addresses the following research questions: 1): What are the essential usability and privacy-enhanced features needed to inform the design and development …


Authenticating Users With 3d Passwords Captured By Motion Sensors, Jing Tian Jan 2018

Authenticating Users With 3d Passwords Captured By Motion Sensors, Jing Tian

Theses and Dissertations

Authentication plays a key role in securing various resources including corporate facilities or electronic assets. As the most used authentication scheme, knowledgebased authentication is easy to use but its security is bounded by how much a user can remember. Biometrics-based authentication requires no memorization but ‘resetting’ a biometric password may not always be possible. Thus, we propose study several behavioral biometrics (i.e., mid-air gestures) for authentication which does not have the same privacy or availability concerns as of physiological biometrics.

In this dissertation, we first propose a user-friendly authentication system Kin- Write that allows users to choose arbitrary, short and …


Toward Biologically-Inspired Self-Healing, Resilient Architectures For Digital Instrumentation And Control Systems And Embedded Devices, Shawkat Sabah Khairullah Jan 2018

Toward Biologically-Inspired Self-Healing, Resilient Architectures For Digital Instrumentation And Control Systems And Embedded Devices, Shawkat Sabah Khairullah

Theses and Dissertations

Digital Instrumentation and Control (I&C) systems in safety-related applications of next generation industrial automation systems require high levels of resilience against different fault classes. One of the more essential concepts for achieving this goal is the notion of resilient and survivable digital I&C systems. In recent years, self-healing concepts based on biological physiology have received attention for the design of robust digital systems. However, many of these approaches have not been architected from the outset with safety in mind, nor have they been targeted for the automation community where a significant need exists. This dissertation presents a new self-healing digital …


Ms. An (Meeting Students’ Academic Needs): A Socially Adaptive Robot Tutor For Student Engagement In Math Education, Karina Liles Jan 2018

Ms. An (Meeting Students’ Academic Needs): A Socially Adaptive Robot Tutor For Student Engagement In Math Education, Karina Liles

Theses and Dissertations

This research presents a new, socially adaptive robot tutor, Ms. An (Meeting Students’ Academic Needs). The goal of this research was to use a decision tree model to develop a socially adaptive robot tutor that predicted and responded to student emotion and performance to actively engage students in mathematics education. The novelty of this multi-disciplinary project is the combination of the fields of HRI, AI, and education. In this study we 1) implemented a decision tree model to classify student emotion and performance for use in adaptive robot tutoring-an approach not applied to educational robotics; 2) presented an intuitive interface …