Digital Commons Network^™

Investigating The Potential Of Blended Feedstocks For Biofuel Production Via Pyrolysis Process: Experimental And Aspen Simulation Approach, Hasan Jawad Hammood Al-Abedi

Doctoral Dissertations

"The development of renewable energy sources has become increasingly urgent considering the climate crisis and the need to reduce greenhouse gas emissions. Pyrolysis, which is decomposition of an organic feedstock without oxygen, is a thermo-chemical process that has garnered significant attention as a promising technology for sustainable energy production, capable of converting biomass and waste materials into biofuels.

The primary objective of this study is to investigate the pyrolysis and co-pyrolysis behaviors of corn stover (CS), refuse-derived fuel (RDF), and oil shale (OS) in equal mass ratios. Utilizing a thermogravimetric analyzer and differential scanning calorimetry (DSC), the co-pyrolysis process is …

Development Of A Comprehensive Multi-Factored Methodology For Identification Of Landslides In The Buffalo National River Of Arkansas, Abdurraouf Okok

Doctoral Dissertations

"In northern Arkansas's Springfield and Boston Mountain Plateaus, distinctive geomorphological landslide features have shown historical continuity. USGS topographic maps (1:24,000, 7.5-minute series) serve as valuable resources for studying terrain characteristics and hydrological patterns.

This study uses a manual mapping approach with high-resolution LiDAR data and geological maps in a GIS environment. The method identifies historic landslide features by analyzing anomalous topographic contour patterns overlaid on LiDAR-derived hillshade maps, revealing various mass movements along the Buffalo National River. Data from the Office of State Geologist and fieldwork reconnaissance were utilized to map older landslide features with high confidence. Some previously unrecognized …

Statistical Analysis Of Electromagnetic Coupling To Printed Circuit Boards, Shengxuan Xia, Victor Khilkevich, Daryl Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

Determining electromagnetic (EM) coupling to printed circuit boards (PCBs) is essential to finding potential EM susceptibilities early in the design process. For realistic PCB structures, analysis usually relies heavily on time-consuming full-wave simulations because of the complexity of the geometries and the lack of analytical solutions. In this paper, we adopt a segmentation approach based on far-field reciprocity which allows for rapid estimation of the voltage induced at trace terminations over frequency, and which is then used to estimate statistical characteristic of coupling across trace geometries. Frequency-domain results can then be used to estimate time-domain responses with appropriate transformations. Super-position …

Uncertainty Quantification For Peec Based On Wasserstein Generative Adversarial Network, Yuan Ping, Yanming Zhang, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

This article proposes a modified generative adversarial network (GAN)-based approach, namely Wasserstein GAN (WGAN), for the uncertainty quantification (UQ) in partial equivalent element circuit (PEEC) models. Initially, the stochastic PEEC is constructed to obtain the sample data of the quantities of interest (QoI). This sample data, along with the fake data from the generator, serves as input for the discriminator in WGAN. The loss function of the generator in WGAN is constructed using the Wasserstein distance to provide a more usable gradient than that in the traditional GAN. By estimating the distribution of sample data using the fake data in …

Evaluation Of Transfer Learning Models On Traumatic Brain Injury Severity Classification, Ngoc Do, Daniel B. Hier, Tayo Obafemi-Ajayi

Electrical and Computer Engineering Faculty Research & Creative Works

After traumatic brain injury (TBI), clinicians use the Glasgow Coma Scale (GCS) to classify patients by severity and radiologists use the Rotterdam score and the Marshall score to classify CT scans by severity. This work investigates a viable efficient low-cost transfer learning model to use MRI images to predict GCS, Rotterdam, and Marshall severity class after TBI. The enhanced transfer learning model architecture integrates multiple fine-tuning steps in which a few layers of the pre-trained model is unfrozen in each iteration so that the neural network is able to learn layer by layer further aspects of the image for better …

Radiated Emission Modeling Of A Wireless Power Transfer System, Hanyu Zhang, Guanghua Li, Viswa Pilla, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

A radiated emission (RE) model of a wireless power transfer (WPT) system is proposed in this paper to help designers predict, analyze, and mitigate the RE issues during the design process. The proposed model employs both full-wave simulation and circuit simulation to derive a transfer function. Subsequently, it predicts the emission level by combining the transfer function with the measured transmitter waveform through a straightforward calculation. The predicted emissions match the measured RE peaks well up to 300 MHz, with the error within 3 dB. The impact of functional parameters, such as load and coil gap distance, is analyzed based …

Low Noise Wireless Sensing In Termite Detection, Wei Zhang, Xiangshu Qi, Yunlong Luo, Alex Qi, Yihong Qi, Gang Feng

Electrical and Computer Engineering Faculty Research & Creative Works

Termites cause enormous financial damages all around the world every year. The majority of research on wireless sensing is always concerned with the various human-centric applications, however, the vast potential of wireless sensing for termite detection is often disregarded. In this article, a Wireless Intelligent Sensing (WISe) millimeter-wave (mmWave) radar system for termite detection is proposed. Here, we design a three-layer architecture with some intelligent resources to monitor the movement signs of the termites. In addition, we present a low noise sensing architecture that minimizes the noise in hardware and digital signal processing, which can reduce the impact of environment …

Dk And Df Characterization Of Low-Loss Dielectric Liquid By Cylindrical Cavity Resonator, Chaofeng Li, Seyedmehdi Mousavi, Reza Asadi, Seyedmostafa Mousavi, Reza Vahdani, Xiaoning Ye, Kai Wang, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

A novel cylindrical cavity resonator-based measurement method was developed to characterize the dielectric property of the low-loss dielectric liquid in the paper. The proposed method can be used to accurately measure the dielectric constant (Dk) and the loss tangent (Df) of the low-loss coolant for signal integrity analysis. The cylindrical cavity resonator works at tangential magnetic (TM010) mode is used in the paper to demonstrate the proposed method. A cylindrical cavity resonator apparatus was designed and investigated using full-wave simulations at first. The relative error of Dk and Df extractions based on the designed apparatus are less than 1% and …

In-Plane And Out-Of-Plane 2-D Microdisplacement Sensor Based On A Single Microwave Resonator With Machine Learning, Shiyu Li, Osamah Alsalman, Jie Huang, Chen Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

Microwave displacement sensors have garnered significant research interest in recent years and have found successful applications in industrial automation and aerospace engineering. However, most microwave sensors are limited to measuring in-plane displacement, with the assumption that out-of-plane displacement remains constant during operation. In this work, we propose and experimentally demonstrate a novel concept for 2-D micro displacement sensing that simultaneously measures both in-plane and out-of-plane displacement. We developed a proof-of-concept sensor system based on a custom-made coaxial cable resonator (CCR) serving as the stator and a rubber-metal heterogeneous plate as the movable part. The in-plane and out-of-plane micromovements of the …

Statistical Eye Diagrams For High-Speed Interconnects Of Packages: A Review, Junyong Park, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

An eye diagram, a critical metric in signal integrity analysis for high-speed interconnects such as packages, interposer, and printed circuit boards (PCBs), is generated by superposition of the received waveform. Obtaining an eye diagram is time-consuming, thus signal integrity analysis is inefficient. This article reviews that have been proposed to overcome this limitation. The statistical eye diagram provides a probability distribution depending on a sampling time and voltage, therefore it can be expanded to other metrics, such as the bit-error rate and shmoo plot. This article introduces previous research on statistical eye diagrams applied to complementary metal-oxide-semiconductors (CMOSs), noise, and …

Optical Fiber Sensors Based On Advanced Vernier Effect - A Review, Wassana Naku, Jie Huang, Chen Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

The Optical Vernier Effect Has Emerged as a Powerful Tool for Enhancing the Sensitivity of Optical Fiber Interferometer-Based Sensors, Ushering in a New Era of Highly Sensitive Fiber Sensing Systems. While Previous Research Has Primarily Focused on the Physical Implementation of Vernier Effect-Based Sensors using Different Combinations of Interferometers, Conventional Vernier Sensors Face Several Challenges. These Include the Stringent Requirements on the Sensor Fabrication Accuracy to Achieve a Large Amplification Factor, the Necessity of using a Source with a Very Large Bandwidth and a Bulky Optical Spectrum Analyzer, and the Associated Complex Signal Demodulation Processes. This Article Delves into Recent …

Addressing Reactive Power Sharing In Parallel Inverter Islanded Microgrid Through Deep Reinforcement Learning, Oroghene Oboreh-Snapps, Sophia A. Strathman, Jonathan Saelens, Arnold Fernandes, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

Parallel Inverter Microgrids (MGs) Present a Significant Challenge in the Form of Inverter-Based Distributed Generators (IBDGs) Connected with Varying Line Impedances, Potentially Leading to Substantial Reactive Power-Sharing Errors (RPSE). This Paper Proposes the Fusion of Data-Driven Control into the Conventional Virtual Synchronous Generator in a Bid to Minimize the Sharing Error. First, All State Variables Associated with Each IBDG in the Microgrid Are Sensed and Used as Input Data for a Deep Reinforcement Learning (DRL) Agent. Next, the DRL Agent, motivated by a Unique Reward Function, is Trained to Satisfy Two Objectives: (1) Ensure the Output Voltage of All IBDGs …

Empowering Urban Traffic Management: Elevated 3d Lidar For Data Collection And Advanced Object Detection Analysis, Nawfal Guefrachi, Hakim Ghazzai, Ahmad Alsharoa

Electrical and Computer Engineering Faculty Research & Creative Works

The 3D object detection capabilities in urban environments have been enormously improved by recent developments in Light Detection and Range (LiDAR) technology. This paper presents a novel framework that transforms the detection and analysis of 3D objects in traffic scenarios by utilizing the power of elevated LiDAR sensors. We are presenting our methodology's remarkable capacity to collect complex 3D point cloud data, which allows us to accurately and in detail capture the dynamics of urban traffic. Due to the limitation in obtaining real-world traffic datasets, we utilize the simulator to generate 3D point cloud for specific scenarios. To support our …

Deep Learning For Uav Detection And Classification Via Radio Frequency Signal Analysis, Prajoy Podder, Maciej Zawodniok, Sanjay Madria

Electrical and Computer Engineering Faculty Research & Creative Works

Unmanned Aerial Vehicles (UAVs) are advertised as great tool that benefits society and humanity. However, UAVs also pose significant security threats ranging from privacy invasions, to interfering with commercial aircraft landing and takeoff, to accidently crashing into vehicles or people, to military or terrorist attacks. Consequently, there is a pressing need to detect and identify UAVs to mitigate such potential risks. While image-based methods are crucial for UAV detection, radio frequency (RF) emissions offer additional valuable insights. Analyzing RF signals, such as those used in UAV-ground station communications, can provide information about UAV types based on distinct frequency usage or …

Additively Manufactured Aperture-Based Fss, Alexander Hook, Doyle T. Motes, Cody Morrow, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency selective surfaces (FSSs) are arrays of patch- or aperture-based elements with specific high frequency reflective and/or transmissive properties. The specific FSS response of a given design is dictated by the element dimensions and spacing relative to adjacent elements (collectively referred to as the unit cell), along with the substrate (and superstrate if applicable) properties. As it relates to sensing, the FSS response may be affected by environmental (e.g., temperature) or structural (e.g., strain) changes. To this end, FSS-based sensors have been considered in recent years for a myriad of sensing applications including structural health monitoring (SHM). Concurrent to this, …

Angle-Dependent Photoinduced Changes Of Near-Infrared Transmission In Amorphous Selenium Films, Kaitlin Hellier, Emily Enlow, Seyedehnajmeh Montazeri, Mina Esmaeelpour, Shiva Abbaszadeh

Electrical and Computer Engineering Faculty Research & Creative Works

Amorphous selenium (a-Se) is a promising semiconductor for a variety of photoconductive applications, predominantly in X-ray detection. In addition, material properties introduce several other potential applications in nonlinear optics. Photodarkening (PD) presents an interesting area of study; when exposed to band-region light, metastable structural changes induce a shift in the band edge and increase tail absorption. In this work, we investigate these effects utilizing a near-infrared (NIR) probe to avoid generating any darkening during beam transmission. We observe an unexpected result; here, we present the effects of band region exposure in NIR transmission (1570 nm). We observe a shift from …

Highly Sensitive Liquid-Level Sensing Based On Microwave Frequency Domain Reflectometry And Interferometry, Chen Zhu, Osamah Alsalman, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency domain reflectometry (FDR) and interferometry are two widely used investigative techniques that have been instrumented using optical and microwave devices for a diverse array of sensing applications. In this paper, we present a highly sensitive liquid-level sensor using a custom hollow coaxial cable transmission line. Measurements of liquid levels with high sensitivity and resolution can be achieved by both FDR and interferometry-based measurements using the same sensor device. We show that FDR-based measurements are more straightforward for liquid-level sensing and are suitable for both small and large variations of liquid level, while interferometry-based measurements provide slightly higher measurement resolution …

Quantifying Wild Pig Disturbance In Pastures And Wetlands Using Unmanned Aerial Vehicle-Derived Imagery, Wesley M. Anderson, Bethany Wight, Raoul K. Boughton

Human–Wildlife Interactions

The use of unmanned aerial vehicles (UAVs) for agricultural and environmental research has increased markedly in recent years, and a key application has been to conduct damage assessments. Invasive wild pigs (Sus scrofa) cause both agricultural and environmental damage, and past studies have utilized UAVs to quantify this damage. Each methodology has advantages, but they also have drawbacks such as high rates of damage omission or reliance upon a near-infrared camera, which may be prohibitively expensive for some land managers and scientists. Our objective was to develop a methodology that could be easily implemented to conduct wild pig …

Flashtags: Evaluating A Novel Deterrent To Reduce Livestock Depredation, C. Aaron Bott, Stewart W. Breck, Tom W. Murphy, Brad A. Freking, Carlos A. López González, David Prause, Corey Peavey, Albert Sommers, Coke Landers, Julie K. Young

Human–Wildlife Interactions

Social tolerance of carnivores can be improved by preventing conflicts through nonlethal predator deterrents (e.g., livestock protection dogs [Canis lupus familiaris] and human presence) that have been used for centuries. However, many livestock producers feel the existing preventative methods are inadequate for extensive production systems where livestock can be spread widely and have less human supervision. To address this issue, we developed and tested a new nonlethal tool called FlashTags to reduce livestock predation. FlashTags are ear tags worn by livestock that flash a random-light pattern at night when motion-triggered. In the first year, we tested the devices …

The Lawlessness Of Sackett V. Epa, William W. Buzbee

Georgetown Law Faculty Publications and Other Works

When the Supreme Court speaks on a disputed statutory interpretation question, its words and edicts undoubtedly are the final judicial word, binding lower courts and the executive branch. Its majority opinions are the law. But the Court’s opinions can nonetheless be assessed for how well they hew to fundamental elements of respect for the rule of law. In particular, law-respecting versus law-neglecting or lawless judicial work by the Court can be assessed in the statutory interpretation, regulatory, and separation of power realms against the following key criteria, which in turn are based on some basic rule of law tenets: analysis …

Fears, Faith, And Facts In Environmental Law, William W. Buzbee

Georgetown Law Faculty Publications and Other Works

Environmental law has long been shaped by both the particular nature of environmental harms and by the actors and institutions that cause such harms or can address them. This nation’s environmental statutes remain far from perfect, and a comprehensive law tailored to the challenges of climate change is still elusive. Nonetheless, America’s environmental laws provide lofty, express protective purposes and findings about reasons for their enactment. They also clearly state health and environmental goals, provide tailored criteria for action, and utilize procedures and diverse regulatory tools that reflect nuanced choices.

But the news is far from good. Despite the ambitious …

Cultural Property: “Progressive Property In Action”, J. Peter Byrne

Georgetown Law Faculty Publications and Other Works

Cultural property law fulfills many of the normative and jurisprudential goals of progressive property theory. Cultural property limits the normal prerogatives of owners in order to give legal substance to the interests of the public or of specially protected non-owners. It recognizes that preservation of and access to heritage resources advance public values such as cultural enrichment and community identity. The proliferation of cultural property laws and their acceptance by courts has occurred despite a resurgent property fundamentalism embraced by the Supreme Court. Thus, this Article seeks to explicate the category of cultural property, its fulfillment of progressive theory, and …

Large Constellations Of Small Satellites: The Good, The Bad, The Ugly, And The Illegal, David A. Koplow

Georgetown Law Faculty Publications and Other Works

The most exciting and far-reaching contemporary developments regarding human activities in outer space arise from the recent drastic reductions in the costs of building, launching, and operating satellites, and from the concomitant sudden emergence of large constellations of small, inexpensive, privately-owned spacecraft. These satellites--devoted to highly remunerative functions such as communications (bringing high-speed, affordable internet to underserved constituencies), remote sensing (facilitating land use planning, weather forecasting, and emergency search and rescue), and support for military operations (in Ukraine and elsewhere)--already number in the thousands and will soon reach the tens of thousands.

But in addition to generating billions of …

Loper Bright In A Larger Interpretive Perspective: Is This Justice Scalia’S Court Anymore?, Victoria Frances Nourse

Georgetown Law Faculty Publications and Other Works

Loper Bright Enterprises v. Raimondo has left administrative lawyers agog: Could the Supreme Court really reverse the “goliath” known as Chevron deference? For those who study the Court’s interpretive landscape more broadly, however, Chevron reversal may not be as unexpected as administrative lawyers believe. This Article will look at Loper Bright by linking three notable interpretive developments: the major questions doctrine, Chevron skepticism, and strict constructions of statutory text. These developments share the same risk: the Court is imposing a new “clarity tax” on both Congress and administrative agencies. Having said this, others’ grave worries about changes in Chevron are …

Computational And Experimental Modeling Of Particle Transport Inside Respiratory Pathways And Indoor Environments, Abir Malakar

Electronic Theses and Dissertations

This thesis aims to explore efficient drug delivery to clinical target sites along the human upper airway that strongly depends on variables associated with the delivery device and the drug formulation, e.g., the device plume angle, particle sizes of drug solution, drug delivery speed of the device, viscosity of the drug solution, delivery axis orientation, and the formulation density. In our investigation, we prioritize the nasopharynx, the primary site of initial viral infection, as the ideal target zone for drug delivery. We have used Large Eddy Simulation and Lagrangian techniques to replicate breathing at 15 L/min and quantify regional drug …

Longevity In Afrikaner Cattle: A Survival Analysis, Allison M. Bot Steffl

Electronic Theses and Dissertations

The Afrikaner breed of cattle is indigenous to South Africa and due to their hardiness was once the most popular breed amongst farmers. The objectives for this study were to: (1) estimate environmental effects (age at first calving, season) and (2) genetic variance affecting longevity in Afrikaner cattle using survival analysis and a Weibull model and (3) evaluate the effect of the Infusion Project on longevity utilizing a Cox model. For the first objective, age at first calving impacted longevity as younger age at first calving was associated with decreased longevity. Season of birth and year of birth also impacted …

Assessing The Performance And Cost Effectiveness Of Rainwater Harvesting For High Tunnel Production Across Climates In The Continental United States, Mustafa Aydogdu

Electronic Theses and Dissertations

Several factors such as global climate change, population growth, urban and agricultural expansion, rising water demand, unequal water distribution, hydro-political conditions, declining water quality, rainwater scarcity, and temperature-induced drought contribute to water resource degradation. Rainwater harvesting (RWH) emerges as a sustainable solution, involving the collection and storage of rainwater for agriculture, livestock, and domestic use. RWH reduces reliance on municipal water, mitigates climate change impacts, and decreases runoff. Conventional RWH systems in the US vary in effectiveness. Increasing storage and water use enhances RWH effectiveness, improving stormwater runoff and reducing potable water use. High tunnel production of vegetable crops has …

Lidar Remote Sensing And The Monitoring Of Brazilian Amazon Forest Structure: Tackling Issues And Finding New Possibilities, Pedro Valle De Carvalho E Oliveira

Electronic Theses and Dissertations

The Amazon is the largest tropical forest in the world and around 60% of it is in Brazil. The amount of carbon stored in the region uncertain, the impacts of land use and climate changes are unknown, and what drives the dynamic of the forest structure is still under a heated debate. Optical remote sensing has been used for a long time to assist the monitoring of the Brazilian Amazon. However, optical remote sensing only allows a comprehensive study from the top of the forest canopy. In contrast, lidar remote sensing of forests can produce robust information regarding the canopy …

Computational Fluid Dynamics Simulation Of Battery Thermal Management System At The Pack Level In Electric Vehicles, Yifan Chen

Electronic Theses and Dissertations

Electric vehicles (EVs) rely heavily on lithium batteries due to their high energy density, despite their tendency to generate excess heat during operation. Managing this heat is crucial for safety and performance. Battery Thermal Management Systems (BTMS) are essential for maintaining optimal battery temperature and mitigating risks like short circuits. This article examines various cooling methods for BTMS, including air and liquid cooling, and discusses the selection of cooling media and layout configurations within battery packs (BPs). It also highlights the importance of combining multiple cooling methods for efficient heat dissipation. Emerging technologies like Phase Change Materials (PCMs) show promise …

A Memory Efficient Deep Recurrent Q-Learning Approach For Autonomous Wildfire Surveillance, Jeremy A. Cantor

UNF Graduate Theses and Dissertations

Previous literature demonstrates that autonomous UAVs (unmanned aerial vehicles) have the po- tential to be utilized for wildfire surveillance. This advanced technology empowers firefighters by providing them with critical information, thereby facilitating more informed decision-making processes. This thesis applies deep Q-learning techniques to the problem of control policy design under the objective that the UAVs collectively identify the maximum number of locations that are under fire, assuming the UAVs can share their observations. The prohibitively large state space underlying the control policy motivates a neural network approximation, but prior work used only convolutional layers to extract spatial fire information from …