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Articles 91 - 120 of 271

Full-Text Articles in Computer Engineering

Modeling Site Specific Urban Propagation Using A Variable Terrain Radiowave Parabolic Equation - Vertical Plane Launch (Vtrpe-Vpl) Hybrid Technique, Pierre Cadette Jan 2020

Modeling Site Specific Urban Propagation Using A Variable Terrain Radiowave Parabolic Equation - Vertical Plane Launch (Vtrpe-Vpl) Hybrid Technique, Pierre Cadette

Electronic Theses and Dissertations, 2020-2023

The development of efficient algorithms for calculating propagation loss in site specific urban environments has been an active area of research for many years. This dissertation demonstrates that, for particular scenarios, a hybrid approach that combines the Variable Terrain Radiowave Parabolic Equation (VTRPE) and Vertical Plane Launch (VPL) models can be used to produce accurate results for a downrange region of interest. The hybrid approach consists of leveraging the 2-D parabolic equation method in the initial propagation region, where backscatter and out of plane energy can be neglected, then transitioning to the more computationally intensive 3-D ray launching method for …


Scalable Communication Frameworks For Multi-Agency Data Sharing, Shafaq Chaudhry Jan 2020

Scalable Communication Frameworks For Multi-Agency Data Sharing, Shafaq Chaudhry

Electronic Theses and Dissertations, 2020-2023

With the rise in frequency and magnitude of natural disasters, there is a need to break down monolithic organizational barriers and engage with community volunteers. This calls for ease of systems interoperability to facilitate communication, data-sharing and scalability of real-time response, essential for crisis communications. We propose two scalable frameworks that enable multi-agency interoperability and real-time data-sharing. The first framework harnesses the power of social media, artificial intelligence, and community volunteers to form an extended rescue-and-response network that alleviates call center burden and augments the finite capacity of dispatch units. Through an "online 9-1-1" service, affected people can request help …


Detecting Small Moving Targets In Infrared Imagery, Adam Cuellar Jan 2020

Detecting Small Moving Targets In Infrared Imagery, Adam Cuellar

Electronic Theses and Dissertations, 2020-2023

Deep convolutional neural networks have achieved remarkable results for detecting large and medium sized objects in images. However, the ability to detect smallobjects has yet to achieve the same level performance. Our focus is on applications that require the accurate detection and localization of small moving objects that are distantfrom the sensor. We first examine the ability of several state-of-the-art object detection networks (YOLOv3 and Mask R-CNN) to find small moving targets in infraredimagery using a publicly released dataset by the US Army Night Vision and Electronic Sensors Directorate. We then introduce a novel Moving Target Indicator Network (MTINet) and …


Multi-Element Multi-Datastream Visible Light Communication Networks, Sifat Ibne Mushfique Jan 2020

Multi-Element Multi-Datastream Visible Light Communication Networks, Sifat Ibne Mushfique

Electronic Theses and Dissertations, 2020-2023

Because of the exponentially increasing demand of wireless data, the Radio Frequency (RF) spectrum crunch is rising rapidly. The amount of available RF spectrum is being shrunk at a very heavy rate, and spectral management is becoming more difficult. Visible Light Communication (VLC) is a recent promising technology complementary to RF spectrum which operates at the visible light spectrum band (400 THz to 780 THz) and it has 10,000 times bigger bandwidth than radio waves (3 kHz to 300 GHz). Due to this tremendous potential, VLC has captured a lot of interest recently as there is already an extensive deployment …


Investigations On The Use Of Hyperthermia For Breast Cancer Treatment, Sreekala Suseela Jan 2020

Investigations On The Use Of Hyperthermia For Breast Cancer Treatment, Sreekala Suseela

Electronic Theses and Dissertations, 2020-2023

Hyperthermia using electromagnetic energy has been proven to be an effective method in the treatment of cancer. Hyperthermia is a therapeutic procedure in which the temperature in the tumor tissue is raised above 42°C without causing any damage to the surrounding healthy tissue. This method has been shown to increase the effectiveness of radiotherapy and chemotherapy. Radio frequencies, microwave frequencies or focused ultrasound can be used to deliver energy to the tumor tissue to attain higher temperatures in the tumor region for hyperthermia application. In this dissertation the use of a near field focused (NFF) microstrip antenna array for the …


Provably Trustworthy And Secure Hardware Design With Low Overhead, Qutaiba Alasad Jan 2020

Provably Trustworthy And Secure Hardware Design With Low Overhead, Qutaiba Alasad

Electronic Theses and Dissertations, 2020-2023

Due to the globalization of IC design in the semiconductor industry and outsourcing of chip manufacturing, 3PIPs become vulnerable to IP piracy, reverse engineering, counterfeit IC, and hardware Trojans. To thwart such attacks, ICs can be protected using logic encryption techniques. However, strong resilient techniques incur significant overheads. SCAs further complicate matters by introducing potential attacks post-fabrication. One of the most severe SCAs is PA attacks, in which an attacker can observe the power variations of the device and analyze them to extract the secret key. PA attacks can be mitigated via adding large extra hardware; however, the overheads of …


Deep Hashing For Image Similarity Search, Ali Al Kobaisi Jan 2020

Deep Hashing For Image Similarity Search, Ali Al Kobaisi

Electronic Theses and Dissertations, 2020-2023

Hashing for similarity search is one of the most widely used methods to solve the approximate nearest neighbor search problem. In this method, one first maps data items from a real valued high-dimensional space to a suitable low dimensional binary code space and then performs the approximate nearest neighbor search in this code space instead. This is beneficial because the search in the code space can be solved more efficiently in terms of runtime complexity and storage consumption. Obviously, for this method to succeed, it is necessary that similar data items be mapped to binary code words that have small …


Extracting Data-Level Parallelism In High-Level Synthesis For Reconfigurable Architectures, Juan Andres Escobedo Contreras Jan 2020

Extracting Data-Level Parallelism In High-Level Synthesis For Reconfigurable Architectures, Juan Andres Escobedo Contreras

Electronic Theses and Dissertations, 2020-2023

High-Level Synthesis (HLS) tools are a set of algorithms that allow programmers to obtain implementable Hardware Description Language (HDL) code from specifications written high-level, sequential languages such as C, C++, or Java. HLS has allowed programmers to code in their preferred language while still obtaining all the benefits hardware acceleration has to offer without them needing to be intimately familiar with the hardware platform of the accelerator. In this work we summarize and expand upon several of our approaches to improve the automatic memory banking capabilities of HLS tools targeting reconfigurable architectures, namely Field-Programmable Gate Arrays or FPGA's. We explored …


Control Strategies For Multi-Controller Multi-Objective Systems, Raaed Al-Azzawi Jan 2020

Control Strategies For Multi-Controller Multi-Objective Systems, Raaed Al-Azzawi

Electronic Theses and Dissertations, 2020-2023

This dissertation's focus is control systems controlled by multiple controllers, each having its own objective function. The control of such systems is important in many practical applications such as economic systems, the smart grid, military systems, robotic systems, and others. To reap the benefits of feedback, we consider and discuss the advantages of implementing both the Nash and the Leader-Follower Stackelberg controls in a closed-loop form. However, closed-loop controls require continuous measurements of the system's state vector, which may be expensive or even impossible in many cases. As an alternative, we consider a sampled closed-loop implementation. Such an implementation requires …


Target Acquisition Performance Improvement With Boost And Restoration Filtering Using Deep-Electron-Well Infrared Detectors, Robert Short Jan 2020

Target Acquisition Performance Improvement With Boost And Restoration Filtering Using Deep-Electron-Well Infrared Detectors, Robert Short

Electronic Theses and Dissertations, 2020-2023

Recent advances in infrared focal plane fabrication have allowed for the production of sensors with small detector size (small pitch) and long integration time (deep electron wells) in large-format arrays. Individually, these are all welcome developments, but we raise the question of whether it is possible to utilize all of these technologies in concert to optimize performance. If so, a key part of such a system will be digital boost filtering, to recover the performance loss due to diffraction blur. We describe a system design concept called PWP (Pitch-Well-Processing) that uses each of these features along with Wiener filtering to …


Pervasive Spectrum Sharing For Improved Wireless Experience, Mostafizur Rahman Jan 2020

Pervasive Spectrum Sharing For Improved Wireless Experience, Mostafizur Rahman

Electronic Theses and Dissertations, 2020-2023

Spectrum sharing among cellular users has been a promising approach to attain better efficiency in the use of the limited spectral bands. The existing dynamic spectrum access techniques include sharing of the licensed spectrum bands by allowing other 'secondary' users to use the bands if the licensee 'primary' user is idle. This primary-secondary spectrum sharing is limited in terms of design space, and may not be sufficient to meet the ever-increasing demand of connectivity and high signal quality to improve the end-users' wireless experience. The next step to increase spectrum efficiency is to design markets where sharing takes place pervasively …


Selective Subtraction: An Extension Of Background Subtraction, Adeel Bhutta Jan 2020

Selective Subtraction: An Extension Of Background Subtraction, Adeel Bhutta

Electronic Theses and Dissertations, 2020-2023

Background subtraction or scene modeling techniques model the background of the scene using the stationarity property and classify the scene into two classes of foreground and background. In doing so, most moving objects become foreground indiscriminately, except for perhaps some waving tree leaves, water ripples, or a water fountain, which are typically "learned" as part of the background using a large training set of video data. Traditional techniques exhibit a number of limitations including inability to model partial background or subtract partial foreground, inflexibility of the model being used, need for large training data and computational inefficiency. In this thesis, …


A Review On Mixed Criticality Methods, Alex Jenkel May 2019

A Review On Mixed Criticality Methods, Alex Jenkel

Recent Advances in Real-Time Systems

Within the study of mixed criticality scheduling, there are many different aspects that must be considered—resources, processor speeds, number of processors, etc.—that make scheduling theories difficult to produce. Two papers address specific aspects of mixed criticality scheduling, and this paper compares the two different methods and also builds upon them.


Normally-Off Computing Design Methodology Using Spintronics: From Devices To Architectures, Arman Roohi May 2019

Normally-Off Computing Design Methodology Using Spintronics: From Devices To Architectures, Arman Roohi

Electronic Theses and Dissertations

Energy-harvesting-powered computing offers intriguing and vast opportunities to dramatically transform the landscape of Internet of Things (IoT) devices and wireless sensor networks by utilizing ambient sources of light, thermal, kinetic, and electromagnetic energy to achieve battery-free computing. In order to operate within the restricted energy capacity and intermittency profile of battery-free operation, it is proposed to innovate Elastic Intermittent Computation (EIC) as a new duty-cycle-variable computing approach leveraging the non-volatility inherent in post-CMOS switching devices. The foundations of EIC will be advanced from the ground up by extending Spin Hall Effect Magnetic Tunnel Junction (SHE-MTJ) device models to realize SHE-MTJ-based …


Heterogeneous Reconfigurable Fabrics For In-Circuit Training And Evaluation Of Neuromorphic Architectures, Ramtin Mohammadizand May 2019

Heterogeneous Reconfigurable Fabrics For In-Circuit Training And Evaluation Of Neuromorphic Architectures, Ramtin Mohammadizand

Electronic Theses and Dissertations

A heterogeneous device technology reconfigurable logic fabric is proposed which leverages the cooperating advantages of distinct magnetic random access memory (MRAM)-based look-up tables (LUTs) to realize sequential logic circuits, along with conventional SRAM-based LUTs to realize combinational logic paths. The resulting Hybrid Spin/Charge FPGA (HSC-FPGA) using magnetic tunnel junction (MTJ) devices within this topology demonstrates commensurate reductions in area and power consumption over fabrics having LUTs constructed with either individual technology alone. Herein, a hierarchical top-down design approach is used to develop the HSCFPGA starting from the configurable logic block (CLB) and slice structures down to LUT circuits and the …


Leveraging The Intrinsic Switching Behaviors Of Spintronic Devices For Digital And Neuromorphic Circuits, Steven Pyle May 2019

Leveraging The Intrinsic Switching Behaviors Of Spintronic Devices For Digital And Neuromorphic Circuits, Steven Pyle

Electronic Theses and Dissertations

With semiconductor technology scaling approaching atomic limits, novel approaches utilizing new memory and computation elements are sought in order to realize increased density, enhanced functionality, and new computational paradigms. Spintronic devices offer intriguing avenues to improve digital circuits by leveraging non-volatility to reduce static power dissipation and vertical integration for increased density. Novel hybrid spintronic-CMOS digital circuits are developed herein that illustrate enhanced functionality at reduced static power consumption and area cost. The developed spin-CMOS D Flip-Flop offers improved power-gating strategies by achieving instant store/restore capabilities while using 10 fewer transistors than typical CMOS-only implementations. The spin-CMOS Muller C-Element developed …


Value-Of-Information Based Data Collection In Underwater Sensor Networks, Fahad Khan May 2019

Value-Of-Information Based Data Collection In Underwater Sensor Networks, Fahad Khan

Electronic Theses and Dissertations

Underwater sensor networks are deployed in marine environments, presenting specific challenges compared to sensor networks deployed in terrestrial settings. Among the major issues that underwater sensor networks face is communication medium limitations that result in low bandwidth and long latency. This creates problems when these networks need to transmit large amounts of data over long distances. A possible solution to address this issue is to use mobile sinks such as autonomous underwater vehicles (AUVs) to offload these large quantities of data. Such mobile sinks are called data mules. Often it is the case that a sensor network is deployed to …


Robotic Automation Of A Cnc Machine, Jace Hovey Jan 2019

Robotic Automation Of A Cnc Machine, Jace Hovey

Honors Undergraduate Theses

Robotic automation of CNC machines is becoming more popular as robot technology advances and becomes more readily available. While some CNC machines can run autonomously with part catchers, vertical milling centers require an external entity to keep the machine running. Collaborative and Industrial robots are the two main selections for automating a vertical CNC milling machine. We investigate specifically which robot type is most effective for machine tending a Haas VF2 vertical milling center. To do this a cell floor plan, risk assessment, overall equipment effectiveness evaluation, and a total cost analysis are performed to compare robots. With this results …


Automated Synthesis Of Unconventional Computing Systems, Amad Ul Hassen Jan 2019

Automated Synthesis Of Unconventional Computing Systems, Amad Ul Hassen

Electronic Theses and Dissertations

Despite decades of advancements, modern computing systems which are based on the von Neumann architecture still carry its shortcomings. Moore's law, which had substantially masked the effects of the inherent memory-processor bottleneck of the von Neumann architecture, has slowed down due to transistor dimensions nearing atomic sizes. On the other hand, modern computational requirements, driven by machine learning, pattern recognition, artificial intelligence, data mining, and IoT, are growing at the fastest pace ever. By their inherent nature, these applications are particularly affected by communication-bottlenecks, because processing them requires a large number of simple operations involving data retrieval and storage. The …


Soft-Error Resilience Framework For Reliable And Energy-Efficient Cmos Logic And Spintronic Memory Architectures, Faris Alghareb Jan 2019

Soft-Error Resilience Framework For Reliable And Energy-Efficient Cmos Logic And Spintronic Memory Architectures, Faris Alghareb

Electronic Theses and Dissertations

The revolution in chip manufacturing processes spanning five decades has proliferated high performance and energy-efficient nano-electronic devices across all aspects of daily life. In recent years, CMOS technology scaling has realized billions of transistors within large-scale VLSI chips to elevate performance. However, these advancements have also continually augmented the impact of Single-Event Transient (SET) and Single-Event Upset (SEU) occurrences which precipitate a range of Soft-Error (SE) dependability issues. Consequently, soft-error mitigation techniques have become essential to improve systems' reliability. Herein, first, we proposed optimized soft-error resilience designs to improve robustness of sub-micron computing systems. The proposed approaches were developed to …


Context-Centric Affect Recognition From Paralinguistic Features Of Speech, Andreas Marpaung Jan 2019

Context-Centric Affect Recognition From Paralinguistic Features Of Speech, Andreas Marpaung

Electronic Theses and Dissertations

As the field of affect recognition has progressed, many researchers have shifted from having unimodal approaches to multimodal ones. In particular, the trends in paralinguistic speech affect recognition domain have been to integrate other modalities such as facial expression, body posture, gait, and linguistic speech. Our work focuses on integrating contextual knowledge into paralinguistic speech affect recognition. We hypothesize that a framework to recognize affect through paralinguistic features of speech can improve its performance by integrating relevant contextual knowledge. This dissertation describes our research to integrate contextual knowledge into the paralinguistic affect recognition process from acoustic features of speech. We …


Improvement Of Data-Intensive Applications Running On Cloud Computing Clusters, Ibrahim Adel Ibrahim Jan 2019

Improvement Of Data-Intensive Applications Running On Cloud Computing Clusters, Ibrahim Adel Ibrahim

Electronic Theses and Dissertations

MapReduce, designed by Google, is widely used as the most popular distributed programming model in cloud environments. Hadoop, an open-source implementation of MapReduce, is a data management framework on large cluster of commodity machines to handle data-intensive applications. Many famous enterprises including Facebook, Twitter, and Adobe have been using Hadoop for their data-intensive processing needs. Task stragglers in MapReduce jobs dramatically impede job execution on massive datasets in cloud computing systems. This impedance is due to the uneven distribution of input data and computation load among cluster nodes, heterogeneous data nodes, data skew in reduce phase, resource contention situations, and …


Simulation, Analysis, And Optimization Of Heterogeneous Cpu-Gpu Systems, Christopher Giles Jan 2019

Simulation, Analysis, And Optimization Of Heterogeneous Cpu-Gpu Systems, Christopher Giles

Electronic Theses and Dissertations

With the computing industry's recent adoption of the Heterogeneous System Architecture (HSA) standard, we have seen a rapid change in heterogeneous CPU-GPU processor designs. State-of-the-art heterogeneous CPU-GPU processors tightly integrate multicore CPUs and multi-compute unit GPUs together on a single die. This brings the MIMD processing capabilities of the CPU and the SIMD processing capabilities of the GPU together into a single cohesive package with new HSA features comprising better programmability, coherency between the CPU and GPU, shared Last Level Cache (LLC), and shared virtual memory address spaces. These advancements can potentially bring marked gains in heterogeneous processor performance and …


Rethinking Routing And Peering In The Era Of Vertical Integration Of Network Functions, Prasun Kanti Dey Jan 2019

Rethinking Routing And Peering In The Era Of Vertical Integration Of Network Functions, Prasun Kanti Dey

Electronic Theses and Dissertations

Content providers typically control the digital content consumption services and are getting the most revenue by implementing an "all-you-can-eat" model via subscription or hyper-targeted advertisements. Revamping the existing Internet architecture and design, a vertical integration where a content provider and access ISP will act as unibody in a sugarcane form seems to be the recent trend. As this vertical integration trend is emerging in the ISP market, it is questionable if existing routing architecture will suffice in terms of sustainable economics, peering, and scalability. It is expected that the current routing will need careful modifications and smart innovations to ensure …


Scalable Map Information Dissemination For Connected And Automated Vehicle Systems, S. M. Osman Gani Jan 2019

Scalable Map Information Dissemination For Connected And Automated Vehicle Systems, S. M. Osman Gani

Electronic Theses and Dissertations

Situational awareness in connected and automated vehicle (CAV) systems becomes particularly challenging in the presence of non-line of sight objects and/or objects beyond the sensing range of local onboard sensors. Despite the fact that fully autonomous driving requires the use of multiple redundant sensor systems, primarily including camera, radar, and LiDAR, the non-line of sight object detection problem still persists due to the inherent limitations of those sensing techniques. To tackle this challenge, the inter-vehicle communication system is envisioned that allows vehicles to exchange self-status updates aiming to extend their effective field of view and thus compensate for the limitations …


Machine Learning And Neural Networks For Real-Time Scheduling, Daniel Hureira, Christian Vartanian Jan 2019

Machine Learning And Neural Networks For Real-Time Scheduling, Daniel Hureira, Christian Vartanian

Recent Advances in Real-Time Systems

This paper aims to serve as an efficient survey of the processes, problems, and methodologies surrounding the use of Neural Networks, specifically Hopfield-Type, in order to solve Hard-Real-Time Scheduling problems. Our primary goal is to demystify the field of Neural Networks research and properly describe the methods in which Real-Time scheduling problems may be approached when using neural networks. Furthermore, to give an introduction of sorts on this niche topic in a niche field. This survey is derived from four main papers, namely: “A Neurodynamic Approach for Real-Time Scheduling via Maximizing Piecewise Linear Utility” and “Scheduling Multiprocessor Job with Resource …


Guided Autonomy For Quadcopter Photography, Saif Alabachi Jan 2019

Guided Autonomy For Quadcopter Photography, Saif Alabachi

Electronic Theses and Dissertations

Photographing small objects with a quadcopter is non-trivial to perform with many common user interfaces, especially when it requires maneuvering an Unmanned Aerial Vehicle (C) to difficult angles in order to shoot high perspectives. The aim of this research is to employ machine learning to support better user interfaces for quadcopter photography. Human Robot Interaction (HRI) is supported by visual servoing, a specialized vision system for real-time object detection, and control policies acquired through reinforcement learning (RL). Two investigations of guided autonomy were conducted. In the first, the user directed the quadcopter with a sketch based interface, and periods of …


Autonomous Discovery And Maintenance Of Mobile Frees-Space-Optical Links, Mahmudur Khan Aug 2018

Autonomous Discovery And Maintenance Of Mobile Frees-Space-Optical Links, Mahmudur Khan

Electronic Theses and Dissertations

Free-Space-Optical (FSO) communication has the potential to play a significant role in future generation wireless networks. It is advantageous in terms of improved spectrum utilization, higher data transfer rate, and lower probability of interception from unwanted sources. FSO communication can provide optical-level wireless communication speeds and can also help solve the wireless capacity problem experienced by the traditional RF-based technologies. Despite these advantages, communications using FSO transceivers require establishment and maintenance of line-of-sight (LOS). We consider autonomous mobile nodes (Unmanned Ground Vehicles or Unmanned Aerial Vehicles), each with one FSO transceiver mounted on a movable head capable of scanning in …


The Subject Librarian Newsletter, Engineering And Computer Science, Spring 2018, Buenaventura "Ven" Basco Mar 2018

The Subject Librarian Newsletter, Engineering And Computer Science, Spring 2018, Buenaventura "Ven" Basco

Libraries' Newsletters

No abstract provided.


Security Of Autonomous Systems Under Physical Attacks: With Application To Self-Driving Cars, Raj Gautam Dutta Jan 2018

Security Of Autonomous Systems Under Physical Attacks: With Application To Self-Driving Cars, Raj Gautam Dutta

Electronic Theses and Dissertations

The drive to achieve trustworthy autonomous cyber-physical systems (CPS), which can attain goals independently in the presence of significant uncertainties and for long periods of time without any human intervention, has always been enticing. Significant progress has been made in the avenues of both software and hardware for fulfilling these objectives. However, technological challenges still exist and particularly in terms of decision making under uncertainty. In an autonomous system, uncertainties can arise from the operating environment, adversarial attacks, and from within the system. As a result of these concerns, human-beings lack trust in these systems and hesitate to use them …