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Articles 241 - 270 of 3445

Full-Text Articles in Engineering

Quadrature Phase-Domain Adpll With Integrated On-Line Amplitude Locked Loop Calibration For 5g Multi-Band Applications, Xiaomeng Zhang Jan 2022

Quadrature Phase-Domain Adpll With Integrated On-Line Amplitude Locked Loop Calibration For 5g Multi-Band Applications, Xiaomeng Zhang

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5th generation wireless systems (5G) have expanded frequency band coverage with the low-band 5G and mid-band 5G frequencies spanning 600 MHz to 4 GHz spectrum. This dissertation focuses on a microelectronic implementation of CMOS 65 nm design of an All-Digital Phase Lock Loop (ADPLL), which is a critical component for advanced 5G wireless transceivers. The ADPLL is designed to operate in the frequency bands of 600MHz-930MHz, 2.4GHz-2.8GHz and 3.4GHz-4.2GHz. Unique ADPLL sub-components include: 1) Digital Phase Frequency Detector, 2) Digital Loop Filter, 3) Channel Bank Select Circuit, and 4) Digital Control Oscillator. Integrated with the ADPLL is a 90-degree active …

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Building An Understanding Of Human Activities In First Person Video Using Fuzzy Inference, Bradley A. Schneider Jan 2022

Building An Understanding Of Human Activities In First Person Video Using Fuzzy Inference, Bradley A. Schneider

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Activities of Daily Living (ADL’s) are the activities that people perform every day in their home as part of their typical routine. The in-home, automated monitoring of ADL’s has broad utility for intelligent systems that enable independent living for the elderly and mentally or physically disabled individuals. With rising interest in electronic health (e-Health) and mobile health (m-Health) technology, opportunities abound for the integration of activity monitoring systems into these newer forms of healthcare. In this dissertation we propose a novel system for describing ’s based on video collected from a wearable camera. Most in-home activities are naturally defined by …

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Reconfigurable Array Control Via Convolutional Neural Networks, Garrett A. Harris Jan 2022

Reconfigurable Array Control Via Convolutional Neural Networks, Garrett A. Harris

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A method for the beam forming control of an array of reconfigurable antennas is presented. The method consists of using two parallel convolutional neural networks (CNNs) to analyze a desired radiation pattern image, or mask, and provide a suggestion for the reconfigurable element state, array shape, and steering weights necessary to obtain the radiation pattern. This research compares beam forming systems designed for three distinct element types: a patch antenna, a reconfigurable square spiral antenna restricted to a single reconfigurable state, and the fully reconfigurable square spiral. The parametric sweeps for the design of the CNNs are presented along with …

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Secure Authenticated Key Exchange For Enhancing The Security Of Routing Protocol For Low-Power And Lossy Networks, Sarah Mohammed Alzahrani Jan 2022

Secure Authenticated Key Exchange For Enhancing The Security Of Routing Protocol For Low-Power And Lossy Networks, Sarah Mohammed Alzahrani

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The current Routing Protocol for Low Power and Lossy Networks (RPL) standard provides three security modes Unsecured Mode (UM), Preinstalled Secure Mode (PSM), and Authenticated Secure Mode (ASM). The PSM and ASM are designed to prevent external routing attacks and specific replay attacks through an optional replay protection mechanism. RPL's PSM mode does not support key replacement when a malicious party obtains the key via differential cryptanalysis since it considers the key to be provided to nodes during the configuration of the network. This thesis presents an approach to implementing a secure authenticated key exchange mechanism for RPL, which ensures …

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Molecular Dynamics Simulation Study Of A Polymer Droplet Transport Over An Array Of Spherical Nanoparticles, Anish Thomas Jan 2022

Molecular Dynamics Simulation Study Of A Polymer Droplet Transport Over An Array Of Spherical Nanoparticles, Anish Thomas

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This study uses molecular dynamics simulations to evaluate the dynamic behavior of a partially wetting polymer droplet driven over a nanostructured interface. We consider the bead-spring model to represent a polymeric liquid that partially wets a rough surface composed of a periodic array of spherical particles. Results show that at sufficiently small values of external force, the droplet remains pinned at the particle's surface, whereas above the threshold its motion consists of alternating periods of pinning and rapid displacements between neighboring particles. The latter process involves large periodic variation of the advancing and receding contact angles due to the attachment …

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Printing, Characterization, And Mechanical Testing Of Additively Manufactured Refractory Metal Alloys, Brianna M. Sexton Jan 2022

Printing, Characterization, And Mechanical Testing Of Additively Manufactured Refractory Metal Alloys, Brianna M. Sexton

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Refractory metal alloys in the tungsten molybdenum rhenium ternary system were additively manufactured using laser power bed fusion. Four ternary alloys with varying concentrations of tungsten, molybdenum, and rhenium were manufactured and manufactured again with an addition of 1 wt% hafnium carbide. Samples were heat treated to heal cracks, reduce porosity, and reduce inhomogeneity. Material microstructure was characterized before and after heat treatment using microscopy, energy dispersive x-ray spectroscopy, and electron backscatter diffraction mapping. Mechanical testing was conducted on both three-point bend specimens and compression specimens, resulting in maximum bending strengths of 677.86 MPa, and maximum compression 0.2% yield strengths …

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Realistic Virtual Human Character Design Strategy And Experience For Supporting Serious Role-Playing Simulations On Mobile Devices, Sindhu Kumari Jan 2022

Realistic Virtual Human Character Design Strategy And Experience For Supporting Serious Role-Playing Simulations On Mobile Devices, Sindhu Kumari

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Promoting awareness of social determinants of health (SDoH) among healthcare providers is important to improve the patient care experience and outcome as it helps providers understand their patients in a better way which can facilitate more efficient and effective communication about health conditions. Healthcare professionals are typically educated about SDoH through lectures, questionaries, or role-play-based approaches; but in today’s world, it is becoming increasingly possible to leverage modern technology to create more impactful and accessible tools for SDoH education. Wright LIFE (Lifelike Immersion for Equity) is a simulation-based training tool especially created for this purpose. It is a mobile app …

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Design, Analysis, And Optimization Of Traffic Engineering For Software Defined Networks, Mohammed Ibrahim Salman Jan 2022

Design, Analysis, And Optimization Of Traffic Engineering For Software Defined Networks, Mohammed Ibrahim Salman

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Network traffic has been growing exponentially due to the rapid development of applications and communications technologies. Conventional routing protocols, such as Open-Shortest Path First (OSPF), do not provide optimal routing and result in weak network resources. Optimal traffic engineering (TE) is not applicable in practice due to operational constraints such as limited memory on the forwarding devices and routes oscillation. Recently, a new way of centralized management of networks enabled by Software-Defined Networking (SDN) made it easy to apply most traffic engineering ideas in practice. \par Toward creating an applicable traffic engineering system, we created a TE simulator for experimenting …

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A Digital Twin For Synchronized Multi-Laser Powder Bed Fusion (M-Lpbf) Additive Manufacturing, Shayna Petitjean Jan 2022

A Digital Twin For Synchronized Multi-Laser Powder Bed Fusion (M-Lpbf) Additive Manufacturing, Shayna Petitjean

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One of the technological challenges in the widespread application of additive manufacturing is the formation of undesired material microstructure and defects. Specifically, in metal additive manufacturing, the microstructural formation of columnar grains in Ti-6Al-4V is common and results in anisotropic mechanical properties and a reduction in properties such as ductility and endurance limit. This work presents the application of hexagonal and circular arrays of synchronized lasers to alter the microstructure of Ti-6Al-4V in favor of equiaxed grains. An anisotropic heat transfer model obtains the temporal/spatial temperature distribution and constructs the solidification map for various process parameters, including laser power, laser …

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Automatically Generating Searchable Fingerprints For Wordpress Plugins Using Static Program Analysis, Chuang Li Jan 2022

Automatically Generating Searchable Fingerprints For Wordpress Plugins Using Static Program Analysis, Chuang Li

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This thesis introduces a novel method to automatically generate fingerprints for WordPress plugins. Our method performs static program analysis using Abstract Syntax Trees (ASTs) of WordPress plugins. The generated fingerprints can be used for identifying these plugins using search engines, which have support critical applications such as proactively identifying web servers with vulnerable WordPress plugins. We have used our method to generate fingerprints for over 10,000 WordPress plugins and analyze the resulted fingerprints. Our fingerprints have also revealed 453 websites that are potentially vulnerable. We have also compared fingerprints for vulnerable plugins and those for vulnerability-free plugins.

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Cmos Wide Tuning Gilbert Mixer With Controllable If Bandwidth In Upcoming Rf Front End For Multi-Band Multi-Standard Applications, Jianfeng Ren Jan 2022

Cmos Wide Tuning Gilbert Mixer With Controllable If Bandwidth In Upcoming Rf Front End For Multi-Band Multi-Standard Applications, Jianfeng Ren

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The current global system for mobile communications, wireless local area, Bluetooth, and ultra-wideband demands a multi-band/multi-standard RF front end that can access all the available bandwidth specifications. Trade-offs occur between power consumption, noise figure, and linearity in CMOS Gilbert mixer wide tuning designs. Besides, it is preferable to have a constant IF bandwidth for different gain settings as the bandwidth varies with the load impedance when an RF receiver is tuned to a higher frequency. My dissertation consists of three parts. First, a tunable constant IF bandwidth Gilbert mixer is introduced for multi-band standard wireless applications such as 802.11 a/b/g …

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Semantics-Driven Abstractive Document Summarization, Amanuel Alambo Jan 2022

Semantics-Driven Abstractive Document Summarization, Amanuel Alambo

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The evolution of the Web over the last three decades has led to a deluge of scientific and news articles on the Internet. Harnessing these publications in different fields of study is critical to effective end user information consumption. Similarly, in the domain of healthcare, one of the key challenges with the adoption of Electronic Health Records (EHRs) for clinical practice has been the tremendous amount of clinical notes generated that can be summarized without which clinical decision making and communication will be inefficient and costly. In spite of the rapid advances in information retrieval and deep learning techniques towards …

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Development Of Enhanced User Interaction And User Experience For Supporting Serious Role-Playing Games In A Healthcare Setting, Mark Lee Alow Jan 2022

Development Of Enhanced User Interaction And User Experience For Supporting Serious Role-Playing Games In A Healthcare Setting, Mark Lee Alow

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Education about implicit bias in clinical settings is essential for improving the quality of healthcare for underrepresented groups. Such a learning experience can be delivered in the form of a serious game simulation. WrightLIFE (Lifelike Immersion for Equity) is a project that combines two serious game simulations, with each addressing the group that faces implicit bias. These groups are individuals that identify as LGBTQIA+ and people with autism spectrum disorder (ASD). The project presents healthcare providers with a training tool that puts them in the roles of the patient and a medical specialist and immerses them in social and clinical …

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Behavior Of 3d Printed Polymeric Triply Periodic Minimal Surface (Tpms) Cellular Structures Under Low Velocity Impact Loads, Jesse James Leiffer Jan 2022

Behavior Of 3d Printed Polymeric Triply Periodic Minimal Surface (Tpms) Cellular Structures Under Low Velocity Impact Loads, Jesse James Leiffer

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Surface-based lattice structures such as triply periodic minimal surface (TPMS) lattices are lightweight structures that are widely being investigated for applications in automotive, aerospace, military, railway, and naval structures. Due to the recent advent of three-dimensional (3D) printing (3DP) technologies, architected cellular materials such as surface- or strut-based periodic lattice cell structures have emerged as a unique class of lightweight metamaterials. These materials possess enhanced strength to weight ratio, high stiffness, exceptional capabilities in reducing noise and vibration, insulating heat, and effective impact energy absorption. Understanding the impact behavior of such materials are important so that they can be reliably …

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A Design Thinking Framework For Human-Centric Explainable Artificial Intelligence In Time-Critical Systems, Paul Benjamin Stone Jan 2022

A Design Thinking Framework For Human-Centric Explainable Artificial Intelligence In Time-Critical Systems, Paul Benjamin Stone

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Artificial Intelligence (AI) has seen a surge in popularity as increased computing power has made it more viable and useful. The increasing complexity of AI, however, leads to can lead to difficulty in understanding or interpreting the results of AI procedures, which can then lead to incorrect predictions, classifications, or analysis of outcomes. The result of these problems can be over-reliance on AI, under-reliance on AI, or simply confusion as to what the results mean. Additionally, the complexity of AI models can obscure the algorithmic, data and design biases to which all models are subject, which may exacerbate negative outcomes, …

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Effect Of Build Geometry And Build Parameters On Microstructure, Fatigue Life, And Tensile Properties Of Additively Manufactured Alloy 718, Anna Dunn Jan 2022

Effect Of Build Geometry And Build Parameters On Microstructure, Fatigue Life, And Tensile Properties Of Additively Manufactured Alloy 718, Anna Dunn

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Additive Manufacturing (AM), particularly laser powder bed fusion, is being studied for use in critical component applications. Tensile and fatigue testing shows differences when built using different laser powers. However, when fabricated in an as-printed geometry, the gauge sections of the two specimens are different and experience different thermal behavior. This work explores microhardness, microstructure size, Niobium segregation, and porosity from samples made with varying laser power and different build geometry sizes representative of the gauge sections in the tensile and fatigue bars. Results show that microhardness varies spatially across the sample. Smaller diameter metallographic coupons (fatigue diameter) have a …

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Fault-Tolerant Control Of Autonomous Ground Vehicle Under Actuator And Sensor, Vaishnavi Janakiraman Jan 2022

Fault-Tolerant Control Of Autonomous Ground Vehicle Under Actuator And Sensor, Vaishnavi Janakiraman

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Unmanned ground vehicles have a wide range of potential applications including autonomous driving, military surveillance, emergency responses, and agricultural robotics, etc. Since such autonomous vehicles need to operate reliably at all times, despite the possible occurrence of faulty behaviors in some system components, the development of fault-tolerant control schemes is a crucial step in ensuring reliable and safe operations. In this research, a fault-tolerant control scheme is developed for a nonlinear ground vehicle model with possible occurrence of both actuator faults in the form of loss of effectiveness (LOE) and sensor bias faults. Based on the vehicle and fault models …

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Deep Understanding Of Technical Documents : Automated Generation Of Pseudocode From Digital Diagrams & Analysis/Synthesis Of Mathematical Formulas, Nikolaos Gkorgkolis Jan 2022

Deep Understanding Of Technical Documents : Automated Generation Of Pseudocode From Digital Diagrams & Analysis/Synthesis Of Mathematical Formulas, Nikolaos Gkorgkolis

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The technical document is an entity that consists of several essential and interconnected parts, often referred to as modalities. Despite the extensive attention that certain parts have already received, per say the textual information, there are several aspects that severely under researched. Two such modalities are the utility of diagram images and the deep automated understanding of mathematical formulas. Inspired by existing holistic approaches to the deep understanding of technical documents, we develop a novel formal scheme for the modelling of digital diagram images. This extends to a generative framework that allows for the creation of artificial images and their …

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The Role Of Son In Chromatin-Mediated Gene Expression, Melissa Jordan Ward Jan 2022

The Role Of Son In Chromatin-Mediated Gene Expression, Melissa Jordan Ward

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Gene expression in mammalian cells requires complex nuclear choreography, and there is increasing evidence that spatiotemporal organization of chromatin and nuclear compartments plays an important role in gene expression. In this dissertation, I examined the function of SON, a splicing factor with a known role in nuclear organization, in chromatin-mediated gene expression. SON association with a transcriptionally inactive U2OS 2-6-3 reporter gene array provided a useful model to study SON’s chromatin dynamics. I demonstrated that SON associates with the inactive but not the activated array, and that SON’s RNA binding domains are not necessary for that association. Second, I discovered …

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Ufuzzer: Lightweight Detection Of Php-Based Unrestricted File Upload Vulnerabilities Via Static-Fuzzing Co-Analysis, Jin Huang, Junjie Zhang, Jialun Liu, Chuang Li Oct 2021

Ufuzzer: Lightweight Detection Of Php-Based Unrestricted File Upload Vulnerabilities Via Static-Fuzzing Co-Analysis, Jin Huang, Junjie Zhang, Jialun Liu, Chuang Li

Computer Science and Engineering Faculty Publications

Unrestricted file upload vulnerabilities enable attackers to upload malicious scripts to a web server for later execution. We have built a system, namely UFuzzer, to effectively and automatically detect such vulnerabilities in PHP-based server-side web programs. Different from existing detection methods that use either static program analysis or fuzzing, UFuzzer integrates both (i.e., static-fuzzing co-analysis). Specifically, it leverages static program analysis to generate executable code templates that compactly and effectively summarize the vulnerability-relevant semantics of a server-side web application. UFuzzer then “fuzzes” these templates in a local, native PHP runtime environment for vulnerability detection. Compared to static-analysis-based methods, UFuzzer preserves …

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Clustering Of Pain Dynamics In Sickle Cell Disease From Sparse, Uneven Samples, Gary K. Nave Jr, Swati Padhee, Amanuel Alambo, Tanvi Banerjee, Nirmish Shah, Daniel M. Abrams Aug 2021

Clustering Of Pain Dynamics In Sickle Cell Disease From Sparse, Uneven Samples, Gary K. Nave Jr, Swati Padhee, Amanuel Alambo, Tanvi Banerjee, Nirmish Shah, Daniel M. Abrams

Computer Science and Engineering Faculty Publications

Irregularly sampled time series data are common in a variety of fields. Many typical methods for drawing insight from data fail in this case. Here we attempt to generalize methods for clustering trajectories to irregularly and sparsely sampled data. We first construct synthetic data sets, then propose and assess four methods of data alignment to allow for application of spectral clustering. We also repeat the same process for real data drawn from medical records of patients with sickle cell disease -- patients whose subjective experiences of pain were tracked for several months via a mobile app. We find that different …

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Uncertainty-Aware Visualization In Medical Imaging - A Survey, Christina Gillmann, Dorothee Saur, Thomas Wischgoll, Gerik Scheuermann Jun 2021

Uncertainty-Aware Visualization In Medical Imaging - A Survey, Christina Gillmann, Dorothee Saur, Thomas Wischgoll, Gerik Scheuermann

Computer Science and Engineering Faculty Publications

Medical imaging (image acquisition, image transformation, and image visualization) is a standard tool for clinicians in order to make diagnoses, plan surgeries, or educate students. Each of these steps is affected by uncertainty, which can highly influence the decision-making process of clinicians. Visualization can help in understanding and communicating these uncertainties. In this manuscript, we aim to summarize the current state-of-the-art in uncertainty-aware visualization in medical imaging. Our report is based on the steps involved in medical imaging as well as its applications. Requirements are formulated to examine the considered approaches. In addition, this manuscript shows which approaches can be …

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Nomophobia Before And After The Covid-19 Pandemic-Can Social Media Be Used To Understand Mobile Phone Dependency, Vaishnavi Visweswaraiah, Tanvi Banerjee, William Romine, Sarah Fryman Jun 2021

Nomophobia Before And After The Covid-19 Pandemic-Can Social Media Be Used To Understand Mobile Phone Dependency, Vaishnavi Visweswaraiah, Tanvi Banerjee, William Romine, Sarah Fryman

Computer Science and Engineering Faculty Publications

No abstract provided.

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Neuro-Symbolic Deductive Reasoning For Cross-Knowledge Graph Entailment, Monireh Ebrahimi, Md Kamruzzaman Sarker, Federico Bianchi, Ning Xie, Aaron Eberhart, Derek Doran, Hyeongsik Kim, Pascal Hitzler Mar 2021

Neuro-Symbolic Deductive Reasoning For Cross-Knowledge Graph Entailment, Monireh Ebrahimi, Md Kamruzzaman Sarker, Federico Bianchi, Ning Xie, Aaron Eberhart, Derek Doran, Hyeongsik Kim, Pascal Hitzler

Computer Science and Engineering Faculty Publications

A significant and recent development in neural-symbolic learning are deep neural networks that can reason over symbolic knowledge graphs (KGs). A particular task of interest is KG entailment, which is to infer the set of all facts that are a logical consequence of current and potential facts of a KG. Initial neural-symbolic systems that can deduce the entailment of a KG have been presented, but they are limited: current systems learn fact relations and entailment patterns specific to a particular KG and hence do not truly generalize, and must be retrained for each KG they are tasked with entailing. We …

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Leveraging Natural Language Processing To Mine Issues On Twitter During The Covid-19 Pandemic, Ankita Agarwal, Preetham Salehundam, Swati Padhee, William Romine, Tanvi Wright State University - Main Campus Mar 2021

Leveraging Natural Language Processing To Mine Issues On Twitter During The Covid-19 Pandemic, Ankita Agarwal, Preetham Salehundam, Swati Padhee, William Romine, Tanvi Wright State University - Main Campus

Computer Science and Engineering Faculty Publications

The recent global outbreak of the coronavirus disease (COVID-19) has spread to all corners of the globe. The international travel ban, panic buying, and the need for self-quarantine are among the many other social challenges brought about in this new era. Twitter platforms have been used in various public health studies to identify public opinion about an event at the local and global scale. To understand the public concerns and responses to the pandemic, a system that can leverage machine learning techniques to filter out irrelevant tweets and identify the important topics of discussion on social media platforms like Twitter …

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Topic-Centric Unsupervised Multi-Document Summarization Of Scientific And News Articles, Amanuel Alambo, Cori Lohstroh, Erik Madaus, Swati Padhee, Brandy Foster, Tanvi Banerjee, Krishnaprasad Thirunarayan, Michael Raymer Mar 2021

Topic-Centric Unsupervised Multi-Document Summarization Of Scientific And News Articles, Amanuel Alambo, Cori Lohstroh, Erik Madaus, Swati Padhee, Brandy Foster, Tanvi Banerjee, Krishnaprasad Thirunarayan, Michael Raymer

Computer Science and Engineering Faculty Publications

Recent advances in natural language processing have enabled automation of a wide range of tasks, including machine translation, named entity recognition, and sentiment analysis. Automated summarization of documents, or groups of documents, however, has remained elusive, with many efforts limited to extraction of keywords, key phrases, or key sentences. Accurate abstractive summarization has yet to be achieved due to the inherent difficulty of the problem, and limited availability of training data. In this paper, we propose a topic-centric unsupervised multi-document summarization framework to generate extractive and abstractive summaries for groups of scientific articles across 20 Fields of Study (FoS) in …

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Can Subjective Pain Be Inferred From Objective Physiological Data? Evidence From Patients With Sickle Cell Disease, Mark J. Panaggio, Daniel M. Abrams, Fan Yang, Tanvi Banerjee, Nirmish R. Shah Mar 2021

Can Subjective Pain Be Inferred From Objective Physiological Data? Evidence From Patients With Sickle Cell Disease, Mark J. Panaggio, Daniel M. Abrams, Fan Yang, Tanvi Banerjee, Nirmish R. Shah

Computer Science and Engineering Faculty Publications

Patients with sickle cell disease (SCD) experience lifelong struggles with both chronic and acute pain, often requiring medical interventMaion. Pain can be managed with medications, but dosages must balance the goal of pain mitigation against the risks of tolerance, addiction and other adverse effects. Setting appropriate dosages requires knowledge of a patient's subjective pain, but collecting pain reports from patients can be difficult for clinicians and disruptive for patients, and is only possible when patients are awake and communicative. Here we investigate methods for estimating SCD patients' pain levels indirectly using vital signs that are routinely collected and documented in …

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Uav Recognition Based On Micro-Doppler Dynamic Attribute-Guided Augmentation Algorithm, Caidan Zhao, Gege Luo, Yilin Wang, Caiyun Chen, Zhiqiang Wu Mar 2021

Uav Recognition Based On Micro-Doppler Dynamic Attribute-Guided Augmentation Algorithm, Caidan Zhao, Gege Luo, Yilin Wang, Caiyun Chen, Zhiqiang Wu

Electrical Engineering Faculty Publications

A micro-Doppler signature (m-DS) based on the rotation of drone blades is an effective way to detect and identify small drones. Deep-learning-based recognition algorithms can achieve higher recognition performance, but they needs a large amount of sample data to train models. In addition to the hovering state, the signal samples of small unmanned aerial vehicles (UAVs) should also include flight dynamics, such as vertical, pitch, forward and backward, roll, lateral, and yaw. However, it is difficult to collect all dynamic UAV signal samples under actual flight conditions, and these dynamic flight characteristics will lead to the deviation of the original …

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Cyclic Damage Accumulation In The Femoral Constructs Made With Cephalomedullary Nails, Farah Hamandi, Alyssa Whitney, Mark H. Stouffer, Michael J. Prayson, Jorn Rittweger, Tarun Goswami Feb 2021

Cyclic Damage Accumulation In The Femoral Constructs Made With Cephalomedullary Nails, Farah Hamandi, Alyssa Whitney, Mark H. Stouffer, Michael J. Prayson, Jorn Rittweger, Tarun Goswami

Biomedical, Industrial & Human Factors Engineering Faculty Publications

Background: The purpose of this study was to evaluate the risk of peri-prosthetic fracture of constructs made with cephalomedullary (CM) long and short nails. The nails were made with titanium alloy (Ti-6Al-4V) and stainless steel (SS 316L). Methods: Biomechanical evaluation of CM nail constructs was carried out with regard to post-primary healing to determine the risk of peri-implant/peri-prosthetic fractures. Therefore, this research comprised of, non-fractured, twenty-eight pairs of cadaveric femora that were randomized and implanted with four types of fixation CM nails resulting in four groups. These constructs were cyclically tested in bi-axial mode for up to 30,000 cycles. All …

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Development Of A Combined Thermal Management And Power Generation System Using A Multi-Mode Rankine Cycle, Nathaniel M. Payne Jan 2021

Development Of A Combined Thermal Management And Power Generation System Using A Multi-Mode Rankine Cycle, Nathaniel M. Payne

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Two sub-systems that present a significant challenge in the development of high performance air vehicle exceeding speeds of Mach 5 are the power generation and thermal management sub-systems. The air friction experienced at high speeds, particularly around the engine, generates large thermal loads that need to be managed. In addition, traditional jet engines do not operate at speeds greater than Mach 3, therefore eliminating the possibility of a rotating power generator. A multi-mode water-based Rankine cycle is an innovative method to address both of these constraints of generating power and providing cooling. Implementing a Rankine cycle-based system allows for the …

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