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Full-Text Articles in Engineering

Detection Of Rotorcraft Landing Sites: An Ai-Based Approach, Abdullah Nasir Jul 2022

Detection Of Rotorcraft Landing Sites: An Ai-Based Approach, Abdullah Nasir

Theses and Dissertations

The updated information about the location and type of rotorcraft landing sites is an essential asset for the Federal Aviation Administration (FAA) and the Department of Transportation (DOT). However, acquiring, verifying, and regularly updating information about landing sites is not straightforward. The lack of current and correct information about landing sites is a risk factor in several rotorcraft accidents and incidents. The current FAA database of rotorcraft landing sites contains inaccurate and missing entries due to the manual updating process. There is a need for an accurate and automated validation tool to identify landing sites from satellite imagery. This thesis …


Distributed Interdigital Capacitor (Idc) Sensing For Cable Insulation Aging And Degradation Detection, Md Nazmul Al Imran Jul 2022

Distributed Interdigital Capacitor (Idc) Sensing For Cable Insulation Aging And Degradation Detection, Md Nazmul Al Imran

Theses and Dissertations

Nuclear power plants (NPPs) contain myriad power, control, instrumentation, and other types of cables. The polymer insulation and jacket materials of such cables degrade over time due to operation and environmental conditions e.g., heat, humidity, and radiation. Since the life span of NPPs may extend beyond 40-50 years regular monitoring of cable insulation and jacket polymers is critical to ensure safe and reliable operation. The agingrelated degradation of cables causes changes in the relative permittivity or dielectric constant of the insulation and jacket materials. Capacitor sensors, if properly designed and developed can measure this change and thus can provide an …


Development Of Micro-Sized Algan Deep Ultraviolet Light Emitting Diodes And Monolithic Photonic Integrated Circuits, Richard Speight Floyd Iii Jul 2022

Development Of Micro-Sized Algan Deep Ultraviolet Light Emitting Diodes And Monolithic Photonic Integrated Circuits, Richard Speight Floyd Iii

Theses and Dissertations

III-Nitride materials-based visible emission LEDs have emerged as a disruptive technology in the fields of lighting,i) communications,ii,iii,iv) and displays.v,vi) Shorter wavelength LEDs in the DUV spectral region (210nm – 360nm) with ultra-wide bandgap (UWBG) AlxGa1-xN active layers are now poised to displace toxic Mercury-based light sources.vii) Over the past decade AlGaN LEDs operating in the deep ultra-violet (DUV) spectral region (200 nm < λemission < 300 nm) have been deployed in novel applications including autonomous drone-based sterilization and sanitization systems, viii) point-of-use water purification systems, ix) photo-therapeutics,x) gas sensors,xi) and non-line-of-sight (NLOS) communications.xii) Similarly, DUV light detectors using ultra-wide bandgap (UWBG) Al …


Non-Intrusive Microwave Surface Wave Technique For Cable Damage And Aging Detection, Ahmed Shah Arman Jul 2022

Non-Intrusive Microwave Surface Wave Technique For Cable Damage And Aging Detection, Ahmed Shah Arman

Theses and Dissertations

Power plants, power distribution and transmission networks, automobiles, aircrafts, trains, industrial manufacturing plants etc. use a variety of cables and wires. The insulation and jacket polymer materials of cables can degrade over time due to operational stressors and environmental conditions. Materials may age, corrode, get chaffed and go missing which if remain undetected and unaddressed can result in major failures. Insulation degradation or damage detection from a distance normally involves the application of direct contact reflectometry techniques. This requires the cable to be disengaged and a diagnostic signal to be directly applied to a cable with a return path. While …


Networked Digital Predictive Control For Modular Dc-Dc Converters, Castulo Aaron De La O Pérez Jul 2022

Networked Digital Predictive Control For Modular Dc-Dc Converters, Castulo Aaron De La O Pérez

Theses and Dissertations

The concept of power electronics building blocks (PEBB) has driven advancements in highly modularized converter systems with many identical subsystems. PEBBs are distributed subsets of converter systems and thus require communication with a control system for their coordination. For this type of system, the communication latency with hard deterministic deadlines is the driving attribute of communication system requirements. However, inherent communication requirements for PEBB-based converter systems also provide opportunities for coordination of energy flow.

Leveraging developments in Gigabit serial communication channels, a control and communication platform architecture for distributed control schemes based on the 2D-Torus communication network topology was developed …


Automated Contingency Management For Water Recycling System, Shijie Tang Jul 2022

Automated Contingency Management For Water Recycling System, Shijie Tang

Theses and Dissertations

NASA’s exploration program envisions the utilization of a Deep Space Habitat (DSH) for human exploration of the space environment in the vicinity of Mars and beyond. Communication latency and extreme limitations of power and life-supporting resources make it imperative to operate the DSH systems in a highly autonomous fashion. One such system is the Environmental Control and Life Support System (ECLSS) which needs to be monitored and optimized to support its designated missions.

Integrated System Health Management (ISHM) technologies have been developed in the past decades to provide a real-time assessment of system health and use this information to improve …


Augmenting Heads-Up Displays With Intelligent Agents: A Human Factors Approach, Grant Edward Morfitt Jun 2022

Augmenting Heads-Up Displays With Intelligent Agents: A Human Factors Approach, Grant Edward Morfitt

Theses and Dissertations

Situational awareness, both tactical and strategic, is essential for humans engaged in complex tasks in civilian and military theaters of operation. Previous work has shown that heads-up displays are effective tools for providing critical information to operators in such situations. Hitherto, heads-up displays have been designed to relay instrument and sensor information to the operator in a topical, timely, and accurate manner. There is a large body of complementary work in the area of human factors that deals with presenting information to a user without detracting from the primary mission. This thesis investigates, measures, and validates the effectiveness of a …


Machine Learning Applications To Static Timing Analysis, Waseem Mohamed Raslan Jun 2022

Machine Learning Applications To Static Timing Analysis, Waseem Mohamed Raslan

Theses and Dissertations

Modeling complex cell behavior is critical for accurate static timing analysis. Effective current source model, ECSM, and composite current source, CCS, waveform data compression became a necessity to reduce the size of technology files and increase the accuracy of the cell characterization data. We used deep learning nonlinear Autoencoders to compress voltage and current waveforms and compared them with singular value decomposition, SVD, approach. Autoencoders gave ~1.67x compression ratio for voltage waveforms better than SVD approach and gave 45x to 55x better compression ratio compared to other lossless techniques like bz2 and gzip. Autoencoders achieved ~1.7x compression ratio for complex …


Methods For Focal Plane Array Resolution Estimation Using Random Laser Speckle In Non-Paraxial Geometries, Phillip J. Plummer Jun 2022

Methods For Focal Plane Array Resolution Estimation Using Random Laser Speckle In Non-Paraxial Geometries, Phillip J. Plummer

Theses and Dissertations

The infrared (IR) imaging community has a need for direct IR detector evaluation due to the continued demand for small pixel pitch detectors, the emergence of strained-layer-super-lattice devices, and the associated lateral carrier diffusion issues. Conventional laser speckle-based modulation transfer function (MTF) estimation is dependent on Fresnel propagation and a wide-sense-stationary input random process, limiting the use of this approach for lambda (wavelength)-scale IR devices. This dissertation develops two alternative methodologies for speckle-based resolution evaluation of IR focal plane arrays (FPAs). Both techniques are formulated using Rayleigh-Sommerfield electric field propagation, making them valid in the non-paraxial geometries dictated for resolution …


Theory And Design Of A Highly Compressed Dropped-Channel Polarimetric Synthetic Aperture Radar, John T. Becker Jun 2022

Theory And Design Of A Highly Compressed Dropped-Channel Polarimetric Synthetic Aperture Radar, John T. Becker

Theses and Dissertations

Compressed sensing (CS) is a recent mathematical technique that leverages the sparsity in certain sets of data to solve an underdetermined system and recover a full set of data from a sub-Nyquist set of measurements of the data. Given the size and sparsity of the data, radar has been a natural choice to apply compressed sensing to, typically in the fast-time and slow-time domains. Polarimetric synthetic aperture radar (PolSAR) generates a particularly large amount of data for a given scene; however, the data tends to be sparse. Recently a technique was developed to recover a dropped PolSAR channel by leveraging …


Effects Of Motion Measurement Errors On Radar Target Detection, Darnell D. Parker Jun 2022

Effects Of Motion Measurement Errors On Radar Target Detection, Darnell D. Parker

Theses and Dissertations

This thesis investigates the relationships present between signal-to-clutter ratios, motion measurement errors, image quality metrics, and the task of target detection, in order to discover what factor merit greater focus in order to attain the highest probability of target detection success. This investigation is accomplished by running a high number of Monte Carlo trials through a coherent target detector and analyzing the results. The aforementioned relationships are demonstrated via sample synthetic aperture radar imagery, histograms, receiver operating characteristics curves, and error bar plots.


Influence Of Materials And Design Parameters On Zinc Oxide Surface Acoustic Devices, Samuel B. Dewhitt Jun 2022

Influence Of Materials And Design Parameters On Zinc Oxide Surface Acoustic Devices, Samuel B. Dewhitt

Theses and Dissertations

This thesis presents research into Zinc Oxide (ZnO) based resonators to include Width Extensional Mode (WEM), Length Extensional Mode (LEM), and Surface Acoustic Wave (SAW) devices. The design and operation of ZnO based SAW devices are investigated further to characterize design parameters and operating modes. Their design, fabrication, and results are discussed in detail. SAW device testing in conjunction with X-Ray Diffractometry (XRD) and Atomic Force Microscopy (AFM) are utilized to characterize ZnO and its deposition parameters on a variety of different substrates and interlayers, with different deposition temperatures and annealing parameters. These substrates include silicon, silicon oxide-on-silicon, and sapphire …


Polarization-Based Image Segmentation And Height Estimation For Interferometric Sar, Augusta J. Vande Hey Jun 2022

Polarization-Based Image Segmentation And Height Estimation For Interferometric Sar, Augusta J. Vande Hey

Theses and Dissertations

To find scatterers in a synthetic aperture radar (SAR) image, a modification is proposed to improve peak region segmentation (PRS) with region merging. The modification considers the polarization of each pixel before it is added to a segment to ensure the segment only contains pixels of the same polarization. Prior to region merging, the polarization of the segments is compared, so that only segments with the same polarization are merged into a single region. The segmented regions are used to find the height of each scatterer through interferometric SAR (IFSAR) processing. Multiple methods of IFSAR are examined to find the …


Full Pattern Analysis And Comparison Of The Center Fed And Offset Fed Cassegrain Antennas With Large Focal Length To Diameter Ratios For High Power Microwave Transmission, Derek W. Mantzke Jun 2022

Full Pattern Analysis And Comparison Of The Center Fed And Offset Fed Cassegrain Antennas With Large Focal Length To Diameter Ratios For High Power Microwave Transmission, Derek W. Mantzke

Theses and Dissertations

High power microwaves (HPM) have been a topic of research since the Cold War era. This paper will present a comparison between two Cassegrain-type antennas: the axially, or center fed, and the offset fed. Specifically, the 10 GHz operating frequency will be investigated with large focal length to diameter () ratios. Beam patterns which encompass the entire radiation pattern will be included for data validation and optimization. The simulations will follow a design of experiments factorial model to ensure all possible combinations of prescribed parameters are included, including an analysis of variance (ANOVA) study to find parameter influence on the …


Integrated Circuits Parasitic Capacitance Extraction Using Machine Learning And Its Application To Layout Optimization, Mohamed Saleh Abouelyazid Saleh May 2022

Integrated Circuits Parasitic Capacitance Extraction Using Machine Learning And Its Application To Layout Optimization, Mohamed Saleh Abouelyazid Saleh

Theses and Dissertations

The impact of parasitic elements on the overall circuit performance keeps increasing from one technology generation to the next. In advanced process nodes, the parasitic effects dominate the overall circuit performance. As a result, the accuracy requirements of parasitic extraction processes significantly increased, especially for parasitic capacitance extraction. Existing parasitic capacitance extraction tools face many challenges to cope with such new accuracy requirements that are set by semiconductor foundries (< 5% error). Although field-solver methods can meet such requirements, they are very slow and have a limited capacity. The other alternative is the rule-based parasitic capacitance extraction methods, which are faster and have a high capacity; however, they cannot consistently provide good accuracy as they use a pre-characterized library of capacitance formulas that cover a limited number of layout patterns. On the other hand, the new parasitic extraction accuracy requirements also added more challenges on existing parasitic-aware routing optimization methods, where simplified parasitic models are used to optimize layouts.

This dissertation provides new solutions for interconnect parasitic capacitance extraction and parasitic-aware routing optimization methodologies in order to cope with the new accuracy requirements of advanced process nodes as follows. …


Transformer Fault Event Detection And Classification Using Pmus, Yadunandan Paudel May 2022

Transformer Fault Event Detection And Classification Using Pmus, Yadunandan Paudel

Theses and Dissertations

Transformer is one of the most reliable components in an electric power system, however its failure has huge opportunity costs for an electric utility. In this work, we detect transformer electrical faults promptly and accurately classify the fault types using voltage/current data from Phasor Measurement Units. Our work can also eliminate uncertainties which are inherent in traditional transformer fault diagnostic techniques like dissolved gas analysis. In this thesis, first, possible causes of transformer failures are discussed, and four common transformer electrical faults are identified. Second, a comprehensive simulation model for electrical faults is developed. Third, fast and efficient abrupt change …


Spatial-Spectral Analysis In Dimensionality Reduction For Hyperspectral Image Classification, Chiranjibi Shah May 2022

Spatial-Spectral Analysis In Dimensionality Reduction For Hyperspectral Image Classification, Chiranjibi Shah

Theses and Dissertations

This dissertation develops new algorithms with different techniques in utilizing spatial and spectral information for hyperspectral image classification. It is necessary to perform spatial and spectral analysis and conduct dimensionality reduction (DR) for effective feature extraction, because hyperspectral imagery consists of a large number of spatial pixels along with hundreds of spectral dimensions.

In the first proposed method, it employs spatial-aware collaboration-competition preserving graph embedding by imposing a spatial regularization term along with Tikhonov regularization in the objective function for DR of hyperspectral imagery. Moreover, Collaboration representation (CR) is an efficient classifier but without using spatial information. Thus, structure-aware collaborative …


Automotive Sensor Fusion Systems For Traffic Aware Adaptive Cruise Control, Jonah T. Gandy May 2022

Automotive Sensor Fusion Systems For Traffic Aware Adaptive Cruise Control, Jonah T. Gandy

Theses and Dissertations

The autonomous driving (AD) industry is advancing at a rapid pace. New sensing technology for tracking vehicles, controlling vehicle behavior, and communicating with infrastructure are being added to commercial vehicles. These new automotive technologies reduce on road fatalities, improve ride quality, and improve vehicle fuel economy. This research explores two types of automotive sensor fusion systems: a novel radar/camera sensor fusion system using a long shortterm memory (LSTM) neural network (NN) to perform data fusion improving tracking capabilities in a simulated environment and a traditional radar/camera sensor fusion system that is deployed in Mississippi State’s entry in the EcoCAR Mobility …


Analysis And Implementation Of Low Fidelity Radar-Based Remote Sensing For Unmanned Aircraft Systems, Matthew Duck May 2022

Analysis And Implementation Of Low Fidelity Radar-Based Remote Sensing For Unmanned Aircraft Systems, Matthew Duck

Theses and Dissertations

Radar-based remote sensing is consistently growing, and new technologies and subsequent techniques for characterization are changing the feasibility of understanding the environment. The emergence of easily accessible unmanned aircraft system (UAS) has broadened the scope of possibilities for efficiently surveying the world. The continued development of low-cost sensing systems has greatly increased the accessibility to characterize physical phenomena. In this thesis, we explore the viability and implementation of using UAS as a means of radar-based remote sensing for ground penetrating radar (GPR) and polarimetric scatterometry. Additionally, in this thesis, we investigate the capabilities and implementations of low-cost microwave technologies for …


A Harmonic Radar System For Honey Bee Tracking To Better Understand Colony Collapse Disorder, William B. Woo May 2022

A Harmonic Radar System For Honey Bee Tracking To Better Understand Colony Collapse Disorder, William B. Woo

Theses and Dissertations

Honey bees are some of the most important pollinators for agriculture in the world and are pivotal to the health of worldwide ecosystems. Like all insects, bees struggle with exposure to parasites, diseases, and other environmental factors that can negatively affect the overall health of the colony. Recently, a new unexplainable phenomenon called Colony Collapse Disorder (CCD) has been wreaking havoc on bee populations worldwide. As a result, a system capable of tracking bees is required to understand the different contributions of chemicals, parasites, etc. to CCD. This research seeks to show data supporting the development of systems for an …


Challenges And Signal Processing Of High Strain Rate Mechanical Testing, Barae Lamdini May 2022

Challenges And Signal Processing Of High Strain Rate Mechanical Testing, Barae Lamdini

Theses and Dissertations

Dynamic testing provides valuable insight into the behavior of materials undergoing fast deformation. During Split-Hopkinson Pressure Bar testing, stress waves are measured using strain gauges as voltage variations that are usually very small. Therefore, an amplifier is required to amplify the data and analyze it. One of the few available amplifiers designed for this purpose is provided by Vishay Micro-Measurements which limits the user’s options when it comes to research or industry. Among the challenges of implementing the Hopkinson technology in the industry are the size and cost of the amplifier. In this work, we propose a novel design of …


Recognizing Traffic Signaling Gestures Through Automotive Sensors., Benjamin James Bartlett May 2022

Recognizing Traffic Signaling Gestures Through Automotive Sensors., Benjamin James Bartlett

Theses and Dissertations

As technology advances with each new day, so do the applications and uses of the different modalities of technology, including transportation, particularly in ADAS vehicles. These systems allow the vehicle to avoid collisions, change lanes, adjust the vehicle’s speed, and more without the need of driver input. However, each sensor type has a weakness, and most advanced driver- assisted system (ADAS) vehicles rely heavily on sensors, such as RGB cameras, radars, and LiDAR sensors. These visual-based sensors may collect very noisy data in cloudy, raining, foggy, or other obscuring phenomena. Radar, on the other hand, does not rely on visual …


Performance Enhancement Of Wide-Range Perception Issues For Autonomous Vehicles, Suvash Sharma May 2022

Performance Enhancement Of Wide-Range Perception Issues For Autonomous Vehicles, Suvash Sharma

Theses and Dissertations

Due to the mission-critical nature of the autonomous driving application, underlying algorithms for scene understanding should be given special care during their development. Mostly, they should be designed with precise consideration of accuracy and run-time. Accuracy should be considered strictly which if compromised leads to faulty interpretation of the environment that may ultimately result in accidental scenarios. On the other hand, run-time holds an important position as the delayed understanding of the scene would hamper the real-time response of the vehicle which again leads to unforeseen accidental cases. These factors come as the functions of several factors such as the …


Electromechanical Fatigue Properties Of Dielectric Elastomer Stretch Sensors Under Orthopaedic Loading Conditions, Andrea Karen Persons May 2022

Electromechanical Fatigue Properties Of Dielectric Elastomer Stretch Sensors Under Orthopaedic Loading Conditions, Andrea Karen Persons

Theses and Dissertations

Fatigue testing of stretch sensors often focuses on high amplitude, low-cycle fatigue (LCF) behavior; however, when used for orthopaedic, athletic, or ergonomic assessments, stretch sensors are subjected to low amplitude, high-cycle fatigue (HCF) conditions. As an added layer of complexity, the fatigue testing of stretch sensors is not only focused on the life of the material comprising the sensor, but also on the reliability of the signal produced during the extension and relaxation of the sensor. Research into the development of a smart sock that can be used to measure the range of motion (ROM) of the ankle joint during …


Age-Of-Information-Aware Load Frequency Control And Stability Analysis, Dan Jiao May 2022

Age-Of-Information-Aware Load Frequency Control And Stability Analysis, Dan Jiao

Theses and Dissertations

Nowadays, modern load frequency control (LFC) systems employ an open communication system, which causes information staleness inevitably to arise. This issue can degrade the regulation performance of LFC and even threaten stability. This thesis introduces age-of-information (AoI) into LFC to describe the information freshness at the control center. Unlike communication delay, AoI can provide real-time information state based on information update rate. In this thesis, a muti-area LFC-AoI model is built to evaluate the update rate effect on LFC performance. Then, an AoI-based stability criterion for discrete LFC systems is built. After that, the AoI margin is proposed and compared …


Potential Of Grid-Scale Pv And Storage Facilities To Participate In Capacity Markets, Nicholas Giovannetti May 2022

Potential Of Grid-Scale Pv And Storage Facilities To Participate In Capacity Markets, Nicholas Giovannetti

Theses and Dissertations

The recent FERC Order 841 has provided an opportunity for grid-scale PV and battery facilities to participate in the capacity market providing ancillary services. Order 841 combined with steadily decreasing PVand battery costs and increasing demand for renewable energy, gives high potential for a PV and battery facility to be economically viable. In this study, an analysis tool is developed as an auxiliary to the PV + Storage + Control + Grid (PSCG) simulation to estimate the megawatts (MW) of dispatchable capacity that can be reliably offered by a PV and storage facility. Limits are based on grid connection, power …


Stability Analysis And Parameters Design Of The Voltage Source Inverter With Lc Filter, Hongzhen Zhang May 2022

Stability Analysis And Parameters Design Of The Voltage Source Inverter With Lc Filter, Hongzhen Zhang

Theses and Dissertations

Voltage source inverters (VSI) are widely used in many applications. In this thesis, the stability of the LC-type single-phase off-grid inverter is investigated and the emphasis is focused on how to extend the effective damping region. The harmonics resonance is the main factor affecting the stability of the system. To deal with this problem, the stability of the system with passive damping is investigated. Aiming at the problem that passive damping methods introduce power loss, Active damping methods are proposed. Considering the system with traditional inductor current feedback active damping cannot be stable when resonance frequency is close to fs/6, …


Model Predictive Control For Grid Scale Pv And Battery, Sahithi Chatradi May 2022

Model Predictive Control For Grid Scale Pv And Battery, Sahithi Chatradi

Theses and Dissertations

Model Predictive Control (MPC) is a control technique that uses prediction data to optimize costs over a given predictive horizon. There are many papers that use this technique to optimize cost in a substantially loaded microgrid, but these techniques are not feasible for utility-scale PV+Storage facility. In this study, MPC is used to optimize the cost for a utility-scale PV+Storage facility, by adding a factor of a possible curtailment. The thesis also presents the various factors that the MPC has in that utility size grid. These factors include line losses, net yield, and curtailment.


Experimental Comparison Of Load Sharing Techniques For Fast Motion In Industrial Machines, Eike Marten Hillrichs May 2022

Experimental Comparison Of Load Sharing Techniques For Fast Motion In Industrial Machines, Eike Marten Hillrichs

Theses and Dissertations

Load sharing and synchronization techniques are essential for modern automation applications where single motor systems cannot meet the application requirements. Evenly sharing the load between multiple motors can increase the output of processes and reduce maintenance efforts due to uneven wear and tear. Rockwell Automation has developed two load sharing techniques for fast motion control applications. In this Thesis, the two load sharing techniques are experimentally compared regarding their ability to evenly share loads and control synchronized motions in a multi motor setup for fast motion. The techniques are compared using a setup with two motors coupled by a timing …


Compact Field Programmable Gate Array Based Physical Unclonable Functions Circuits, Yangpingqing Hu May 2022

Compact Field Programmable Gate Array Based Physical Unclonable Functions Circuits, Yangpingqing Hu

Theses and Dissertations

The Physical Unclonable Functions (PUFs) is a candidate to provide a secure solid root source for identification and authentication applications. It is precious for FPGA-based systems, as FPGA designs are vulnerable to IP thefts and cloning. Ideally, the PUFs should have strong random variations from one chip to another, and thus each PUF is unique and hard to replicate. Also, the PUFs should be stable over time so that the same challenge bits always yield the same result. Correspondingly, one of the major challenges for FPGA-based PUFs is the difficulty of avoiding systematic bias in the integrated circuits but also …