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Electronic Theses and Dissertations, 2020-

Theses/Dissertations

2020

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The Dollar General: Continuous Custom Gesture Recognition Techniques At Everyday Low Prices, Eugene Taranta Jan 2020

The Dollar General: Continuous Custom Gesture Recognition Techniques At Everyday Low Prices, Eugene Taranta

Electronic Theses and Dissertations, 2020-

Humans use gestures to emphasize ideas and disseminate information. Their importance is apparent in how we continuously augment social interactions with motion—gesticulating in harmony with nearly every utterance to ensure observers understand that which we wish to communicate, and their relevance has not escaped the HCI community's attention. For almost as long as computers have been able to sample human motion at the user interface boundary, software systems have been made to understand gestures as command metaphors. Customization, in particular, has great potential to improve user experience, whereby users map specific gestures to specific software functions. However, custom gesture recognition …


Algorithms And Applications Of Novel Capsule Networks, Rodney Lalonde Jan 2020

Algorithms And Applications Of Novel Capsule Networks, Rodney Lalonde

Electronic Theses and Dissertations, 2020-

Convolutional neural networks, despite their profound impact in countless domains, suffer from significant shortcomings. Linearly-combined scalar feature representations and max pooling operations lead to spatial ambiguities and a lack of robustness to pose variations. Capsule networks can potentially alleviate these issues by storing and routing the pose information of extracted features through their architectures, seeking agreement between the lower-level predictions of higher-level poses at each layer. In this dissertation, we make several key contributions to advance the algorithms of capsule networks in segmentation and classification applications. We create the first ever capsule-based segmentation network in the literature, SegCaps, by introducing …


Efficient String Algorithms With Applications In Bioinformatics, Sahar Hooshmand Jan 2020

Efficient String Algorithms With Applications In Bioinformatics, Sahar Hooshmand

Electronic Theses and Dissertations, 2020-

The work presented in this dissertation deals with establishing efficient methods for solving some algorithmic problems, which have applications to Bioinformatics. After a short introduction in Chapter 1, an algorithm for genome mappability problem is presented in Chapter 2. Genome mappability is a measure for the approximate repeat structure of the genome with respect to substrings of specific length and a tolerance to define the number of mismatches. The similarity between reads is measured by using the Hamming distance function. Genome mappability is computed for each position in the string and has several applications in designing high-throughput short-read sequencing experiments. …


The Effects Of Gesture Presentation In Video Games, Jack Oakley Jan 2020

The Effects Of Gesture Presentation In Video Games, Jack Oakley

Electronic Theses and Dissertations, 2020-

As everyday and commonplace technology continues to move toward touch devices and virtual reality devices, more and more video games are using gestures as forms of gameplay. While there is much research focused on gestures as user interface navigation methods, we wanted to look into how gestures affect gameplay when used as a gameplay mechanic. In particular, we set out to determine how different ways of presenting gestures might affect the game's difficulty and flow. We designed two versions of a zombie game where the zombies are killed by drawing gestures. The first version of the game is a touchscreen-based …


Action Recognition In Still Images: Confluence Of Multilinear Methods And Deep Learning, Marjaneh Safaei Jan 2020

Action Recognition In Still Images: Confluence Of Multilinear Methods And Deep Learning, Marjaneh Safaei

Electronic Theses and Dissertations, 2020-

Motion is a missing information in an image, however, it is a valuable cue for action recognition. Thus, lack of motion information in a single image makes action recognition for still images inherently a very challenging problem in computer vision. In this dissertation, we show that both spatial and temporal patterns provide crucial information for recognizing human actions. Therefore, action recognition depends not only on the spatially-salient pixels, but also on the temporal patterns of those pixels. To address the challenge caused by the absence of temporal information in a single image, we introduce five effective action classification methodologies along …


Reconstruction Of Bacterial Strain Genomes From Shotgun Metagenomic Reads, Xin Li Jan 2020

Reconstruction Of Bacterial Strain Genomes From Shotgun Metagenomic Reads, Xin Li

Electronic Theses and Dissertations, 2020-

It is necessary to study bacterial strains in environmental samples. The environmental samples are mixed DNA samples collected from the ocean, soil, lake, human body sites, etc. In a natural environment, they provide us new insights into the diversity of our earth. As for bacterial strains on or inside human bodies, to select the proper treatment for diseases caused by bacterial strains, it is critical to identify the corresponding strains and reconstruct their genomes. However, it is a challenge to do so with the DNA from a large number of unknown microbial species mixed together in an environmental sample. The …


Computational Methods For Discovery And Analysis Of Rna Structural Motifs, Shahidul Islam Jan 2020

Computational Methods For Discovery And Analysis Of Rna Structural Motifs, Shahidul Islam

Electronic Theses and Dissertations, 2020-

Understanding the 3D structural properties of RNAs will play a critical role in identifying their functional characteristics and designing new RNAs for RNA-based therapeutics and nanotechnology. In an attempt to achieve a better insight into RNAs, biochemical experiments have been conducted to produce data with positional details of atoms in RNA structures. This data has created opportunities for applying computational analysis to solve various biological problems. In this dissertation, we have addressed annotation issues of base-pairing interactions in the low-resolution structure data and presented new methods to analyze RNA structural motifs. Annotating base-pairing interactions is one of the critical steps …


Algorithms For Inferring Multiple Microbial Networks, Sahar Tavakoli Jan 2020

Algorithms For Inferring Multiple Microbial Networks, Sahar Tavakoli

Electronic Theses and Dissertations, 2020-

The interactions among the constituent members of a microbial community play a major role in determining the overall behavior of the community and the abundance levels of its members. These interactions can be modeled using a network whose nodes represent microbial taxa and edges represent pairwise interactions. A microbial network is a weighted graph that is constructed from a sample-taxa count matrix and can be used to model co-occurrences and/or interactions of the constituent members of a microbial community. The nodes in this graph represent microbial taxa and the edges represent pairwise associations amongst these taxa. A microbial network is …


Equivariance And Invariance For Robust Unsupervised And Semi-Supervised Learning, Liheng Zhang Jan 2020

Equivariance And Invariance For Robust Unsupervised And Semi-Supervised Learning, Liheng Zhang

Electronic Theses and Dissertations, 2020-

Although there is a great success of applying deep learning on a wide variety of tasks, it heavily relies on a large amount of labeled training data, which could be hard to obtain in many real scenarios. To address this problem, unsupervised and semi-supervised learning emerge to take advantage of the plenty of cheap unlabeled data to improve the model generalization. In this dissertation, we claim that equivariant and invariance are two critical criteria to approach robust unsupervised and semi-supervised learning. The idea is as follows: the features of a robust model ought to be sufficiently informative and equivariant to …


3d Localization Of Defects In Facility Inspections, Nicholas Califano Jan 2020

3d Localization Of Defects In Facility Inspections, Nicholas Califano

Electronic Theses and Dissertations, 2020-

Wind tunnels are crucial facilities that support the aerospace industry. However, these facilities are large, complex, and pose unique maintenance and inspection requirements. Manual inspections to identify defects such as cracks, missing fasteners, leaks, and foreign objects are important but labor and schedule intensive. The goal of this thesis is to utilize small Unmanned Aircraft Systems with onboard cameras and computer vision-based analysis to automate the inspection of the interior and exterior of NASA's critical wind tunnel facilities. Missing fasteners are detected as the defect class, and existing fasteners are detected to provide potential future missing fastener sites for preventative …


Novel Computational Approaches For Multidimensional Brain Image Analysis, Harish Raviprakash Jan 2020

Novel Computational Approaches For Multidimensional Brain Image Analysis, Harish Raviprakash

Electronic Theses and Dissertations, 2020-

The overall goal of this dissertation is focused on addressing challenging problems in 1D, 2D/3D and 4D neuroimaging by developing novel algorithms that combine signal processing and machine learning techniques. One of these challenging tasks is the accurate localization of the eloquent language cortex in brain resection pre-surgery patients. This is especially important since inaccurate localization can lead to diminshed functionalities and thus, a poor quality of life for the patient. The first part of this dissertation addresses this problem in the case of drug-resistant epileptic patients. We propose a novel machine learning based algorithm to establish an alternate electrical …


Analyzing User Behavior In Collaborative Environments, Samaneh Saadat Jan 2020

Analyzing User Behavior In Collaborative Environments, Samaneh Saadat

Electronic Theses and Dissertations, 2020-

Discrete sequences are the building blocks for many real-world problems in domains including genomics, e-commerce, and social sciences. While there are machine learning methods to classify and cluster sequences, they fail to explain what makes groups of sequences distinguishable. Although in some cases having a black box model is sufficient, there is a need for increased explainability in research areas focused on human behaviors. For example, psychologists are less interested in having a model that predicts human behavior with high accuracy and more concerned with identifying differences between actions that lead to divergent human behavior. This dissertation presents techniques for …


Video Content Understanding Using Text, Amir Mazaheri Jan 2020

Video Content Understanding Using Text, Amir Mazaheri

Electronic Theses and Dissertations, 2020-

The rise of the social media and video streaming industry provided us a plethora of videos and their corresponding descriptive information in the form of concepts (words) and textual video captions. Due to the mass amount of available videos and the textual data, today is the best time ever to study the Computer Vision and Machine Learning problems related to videos and text. In this dissertation, we tackle multiple problems associated with the joint understanding of videos and text. We first address the task of multi-concept video retrieval, where the input is a set of words as concepts, and the …


Endpoints And Interdependencies In Internet Of Things Residual Artifacts: Measurements, Analyses, And Insights Into Defenses, Jinchun Choi Jan 2020

Endpoints And Interdependencies In Internet Of Things Residual Artifacts: Measurements, Analyses, And Insights Into Defenses, Jinchun Choi

Electronic Theses and Dissertations, 2020-

The usage of Internet of Things (IoT) devices is growing fast. Moreover, the lack of security measures among the IoT devices and their persistent online connection give adversaries an opportunity to exploit them for multiple types of attacks, such as distributed denial-of-service (DDoS). To understand the risks of IoT devices, we analyze IoT malware from an endpoint standpoint. We investigate the relationship between endpoints infected and attacked by IoT malware, and gain insights into the underlying dynamics in the malware ecosystem. We observe the affinities and different patterns among endpoints. Towards this, we reverse-engineer 2,423 IoT malware samples and extract …


Improving The Security Of Critical Infrastructure: Metrics, Measurements, And Analysis, Jeman Park Jan 2020

Improving The Security Of Critical Infrastructure: Metrics, Measurements, And Analysis, Jeman Park

Electronic Theses and Dissertations, 2020-

In this work, we propose three important contributions needed in the process of improving the security of the critical infrastructure: metrics, measurement, and analysis. To improve security, metrics are key to ensuring the accuracy of the assessment and evaluation. Measurements are the core of the process of identifying the causality and effectiveness of various behaviors, and accurate measurement with the right assumptions is a cornerstone for accurate analysis. Finally, contextualized analysis essential for understanding measurements. Different results can be derived for the same data according to the analysis method, and it can serve as a basis for understanding and improving …


Separating Content Selection From Surface Realization In Neural Text Summarization, Logan Lebanoff Jan 2020

Separating Content Selection From Surface Realization In Neural Text Summarization, Logan Lebanoff

Electronic Theses and Dissertations, 2020-

Text summarization is a rapidly growing field with many new innovations. End-to-end models using the sequence-to-sequence architecture achieve high scores according to automatic metrics on standard datasets. However, they frequently generate summaries that are factually inconsistent with the original article -- a vital problem to be solved before the summaries can be used in real-world applications. In addition, they are not generalizable to new domains, especially those with few training examples. In this dissertation, we propose to explicitly separate the two steps of content selection and surface realization in summarization. Content selection is the process of choosing important words/phrases/sentences from …


Improving Security Of Crypto Wallets In Blockchain Technologies, Hossein Rezaeighaleh Jan 2020

Improving Security Of Crypto Wallets In Blockchain Technologies, Hossein Rezaeighaleh

Electronic Theses and Dissertations, 2020-

A big challenge in blockchain and cryptocurrency is securing the private key from potential hackers. Nobody can rollback a transaction made with a stolen key once the network confirms it. The technical solution to protect private keys is the cryptocurrency wallet, software, hardware, or a combination to manage the keys. In this dissertation, we try to investigate the significant challenges in existing cryptocurrency wallets and propose innovative solutions. Firstly, almost all cryptocurrency wallets suffer from the lack of a secure and convenient backup and recovery process. We offer a new cryptographic scheme to securely back up a hardware wallet relying …


Towards Large-Scale And Robust Code Authorship Identification With Deep Feature Learning, Mohammed Abuhamad Jan 2020

Towards Large-Scale And Robust Code Authorship Identification With Deep Feature Learning, Mohammed Abuhamad

Electronic Theses and Dissertations, 2020-

Successful software authorship identification has both software forensics applications and privacy implications. However, the process requires an efficient extraction of quality authorship attributes. The extraction of such attributes is very challenging due to several factors such as the variety of software formats, number of available samples, and possible obfuscation or adversarial manipulation. We focus on software authorship identification from three central perspectives: large-scale single-authored software, real-world multi-authored software, and the robustness assessment of code authorship identification methods against adversarial attacks. First, we propose DL-CAIS, a deep Learning-based approach for software authorship attribution, that facilitates large-scale, format-independent, language-oblivious, and obfuscation-resilient software …


Deep Recurrent Networks For Gesture Recognition And Synthesis, Mehran Maghoumi Jan 2020

Deep Recurrent Networks For Gesture Recognition And Synthesis, Mehran Maghoumi

Electronic Theses and Dissertations, 2020-

It is hard to overstate the importance of gesture-based interfaces in many applications nowadays. The adoption of such interfaces stems from the opportunities they create for incorporating natural and fluid user interactions. This highlights the importance of having gesture recognizers that are not only accurate but also easy to adopt. The ever-growing popularity of machine learning has prompted many application developers to integrate automatic methods of recognition into their products. On the one hand, deep learning often tops the list of the most powerful and robust recognizers. These methods have been consistently shown to outperform all other machine learning methods …


Interdisciplinary Cybersecurity For Resilient Cyberdefense, Rachid Ait Maalem Lahcen Jan 2020

Interdisciplinary Cybersecurity For Resilient Cyberdefense, Rachid Ait Maalem Lahcen

Electronic Theses and Dissertations, 2020-

Cybersecurity's role is to protect confidentiality, integrity, and availability of enterprise assets. Confidentiality secures data from theft, integrity mitigates modification of data in a malicious way, and availability assures continuation of systems' access and services. However, achieving these goals is difficult due to the mushrooming of various cyber attackers that come from individuals or state actors with motives ranging from ideological, financial, state-sponsored espionage, revenge, or simple curiosity and boredom. The difficulty also lies in the complexity of the cyber layers that are not well studied. Layers that interconnect and require effective communication and collaboration. This effectiveness is still lacking …


High Performance And Secure Execution Environments For Emerging Architectures, Mazen Alwadi Jan 2020

High Performance And Secure Execution Environments For Emerging Architectures, Mazen Alwadi

Electronic Theses and Dissertations, 2020-

Energy-efficiency and performance have been the driving forces of system architectures and designers in the last century. Given the diversity of workloads and the significant performance and power improvements when running workloads on customized processing elements, system vendors are drifting towards new system architectures (e.g., FAM or HMM). Such architectures are being developed with the purpose of improving the system's performance, allow easier data sharing, and reduce the overall power consumption. Additionally, current computing systems suffer from a very wide attack surface, mainly due to the fact that such systems comprise of tens to hundreds of sub-systems that could be …


Design Of Ternary Operations Utilizing Flow-Based Computing, James Pyrich Jan 2020

Design Of Ternary Operations Utilizing Flow-Based Computing, James Pyrich

Electronic Theses and Dissertations, 2020-

The development of algorithms and circuit designs that exploit devices that have the ability to persist multiple values will lead to alternative technologies to overcome the issues caused by the end of Dennard scaling and slowing of Moore's Law. Flow-based designs have been used to develop binary adders and multipliers. Data stored on non-volatile memristors are used to direct the flow of current through nanowires arranged in a crossbar. The algorithmic design of the flow-based crossbar is fast, compact, and efficient. In this paper, we seek to automate the discovery of flow-based designs of ternary circuits utilizing memristive crossbars.


Towards Robust Artificial Intelligence Systems, Sunny Raj Jan 2020

Towards Robust Artificial Intelligence Systems, Sunny Raj

Electronic Theses and Dissertations, 2020-

Adoption of deep neural networks (DNNs) into safety-critical and high-assurance systems has been hindered by the inability of DNNs to handle adversarial and out-of-distribution input. State-of-the-art DNNs misclassify adversarial input and give high confidence output for out-of-distribution input. We attempt to solve this problem by employing two approaches, first, by detecting adversarial input and, second, by developing a confidence metric that can indicate when a DNN system has reached its limits and is not performing to the desired specifications. The effectiveness of our method at detecting adversarial input is demonstrated against the popular DeepFool adversarial image generation method. On a …


Explore And Design Novel Structures For More Efficient And Better Deep Convolutional Neural Networks, Min Wang Jan 2020

Explore And Design Novel Structures For More Efficient And Better Deep Convolutional Neural Networks, Min Wang

Electronic Theses and Dissertations, 2020-

Deep Convolutional Neural Networks have achieved remarkable performance on visual recognition problems, and have been extensively adopted in real-world applications, such as Apple's Face ID security system, autonomous driving cars, and automatic image tagging in online album services. One major concern in the development of CNNs is that their computational complexity grows along with the increase in their accuracy. Therefore, there is a continuous demand to find the right balance between accuracy and complexity in the design of CNN models. This dissertation focuses on designing various novel structures to enhance the performance of CNNs and their efficiency. Our efforts fall …


Decentralized Adaptable Task Allocation For Ongoing Tasks, Vera Kazakova Jan 2020

Decentralized Adaptable Task Allocation For Ongoing Tasks, Vera Kazakova

Electronic Theses and Dissertations, 2020-

This thesis extends an existing bio-inspired model for decentralized task allocation and benchmarks it against alternative approaches to assess robustness in dynamic conditions, applicability to domains with ongoing and hierarchical tasks, and scalability to large teams of agents. The work addresses decentralized task allocation of simple non-communicating agents in dynamic environments of multiple tasks. Multi-area patrolling is used as the sample domain: specific number of agents is required to successfully patrol each area on each timestep, indefinitely, until the system's security needs. Agents must individually decide whether to patrol and where (i.e., task availability is not limited by task demand …


Navigating Immersive And Interactive Vr Environments With Connected 360° Panoramas, Samuel Cosgrove Jan 2020

Navigating Immersive And Interactive Vr Environments With Connected 360° Panoramas, Samuel Cosgrove

Electronic Theses and Dissertations, 2020-

Emerging research is expanding the idea of using 360-degree spherical panoramas of real-world environments for use in "360 VR" experiences beyond video and image viewing. However, most of these experiences are strictly guided, with few opportunities for interaction or exploration. There is a desire to develop experiences with cohesive virtual environments created with 360 VR that allow for choice in navigation, versus scripted experiences with limited interaction. Unlike standard VR with the freedom of synthetic graphics, there are challenges in designing appropriate user interfaces (UIs) for 360 VR navigation within the limitations of fixed assets. To tackle this gap, we …


Stochastic Sampling And Machine Learning Techniques For Social Media State Production, Neda Hajiakhoond Bidoki Jan 2020

Stochastic Sampling And Machine Learning Techniques For Social Media State Production, Neda Hajiakhoond Bidoki

Electronic Theses and Dissertations, 2020-

The rise in the importance of social media platforms as communication tools has been both a blessing and a curse. For scientists, they offer an unparalleled opportunity to study human social networks. However, these platforms have also been used to propagate misinformation and hate speech with alarming velocity and frequency. The overarching aim of our research is to leverage the data from social media platforms to create and evaluate a high-fidelity, at-scale computational simulation of online social behavior which can provide a deep quantitative understanding of adversaries' use of the global information environment. Our hope is that this type of …


Towards Scalable Network Traffic Measurement With Sketches, Rhongho Jang Jan 2020

Towards Scalable Network Traffic Measurement With Sketches, Rhongho Jang

Electronic Theses and Dissertations, 2020-

Driven by the ever-increasing data volume through the Internet, the per-port speed of network devices reached 400 Gbps, and high-end switches are capable of processing 25.6 Tbps of network traffic. To improve the efficiency and security of the network, network traffic measurement becomes more important than ever. For fast and accurate traffic measurement, managing an accurate working set of active flows (WSAF) at line rates is a key challenge. WSAF is usually located in high-speed but expensive memories, such as TCAM or SRAM, and thus their capacity is quite limited. To scale up the per-flow measurement, we pursue three thrusts. …


On Patching Learning Discrepancies In Neural Network Training, Mohamed Elfeki Jan 2020

On Patching Learning Discrepancies In Neural Network Training, Mohamed Elfeki

Electronic Theses and Dissertations, 2020-

Neural network's ability to model data patterns proved to be immensely useful in a plethora of practical applications. However, using the physical world's data can be problematic since it is often cluttered, crowded with scattered insignificant patterns, contain unusual compositions, and widely infiltrated with biases and imbalances. Consequently, training a neural network to find meaningful patterns in seas of chaotic data points becomes virtually as hard as finding a needle in a haystack. Specifically, attempting to simulate real-world multi-modal noisy distributions with high precision leads the network to learn an ill-informed inference distribution. In this work, we discuss four techniques …


Multi-Agent Reinforcement Learning For Defensive Escort Teams, Hassam Sheikh Jan 2020

Multi-Agent Reinforcement Learning For Defensive Escort Teams, Hassam Sheikh

Electronic Theses and Dissertations, 2020-

Reinforcement learning has been applied to solve several real world challenging problems, from robotics to data center cooling. Similarly, adaption of reinforcement learning for multi-agent systems facilitated applications such as optimal multi-robot control and analysis of social-dilemmas. In this dissertation, we show that multi-agent reinforcement learning algorithms suffer from several stability issues such as multi-scenario learning, unstable training in dual-reward setting, overestimation bias and value function collapse, and provide solutions to each of these problems respectively. Several contributions of this dissertation have been formalized within the framework of a defensive escort team problems, a scenario where a team of learning …