Engineering Commons^™

Bevers: A General, Simple, And Performant Framework For Automatic Fact Verification, Mitchell Dehaven

School of Computing: Dissertations, Theses, and Student Research

Fact verification has become an important process, primarily done manually by humans, to verify the authenticity of claims and statements made online. Increasingly, social media companies have utilized human effort to debunk false claims on their platforms, opting to either tag the content as misleading or false, or removing it entirely to combat misinformation on their sites. In tandem, the field of automatic fact verification has become a subject of focus among the natural language processing (NLP) community, spawning new datasets and research. The most popular dataset is the Fact Extraction and VERification (FEVER) dataset. In this thesis an end-to-end …

Attention In The Faithful Self-Explanatory Nlp Models, Mostafa Rafaiejokandan

School of Computing: Dissertations, Theses, and Student Research

Deep neural networks (DNNs) can perform impressively in many natural language processing (NLP) tasks, but their black-box nature makes them inherently challenging to explain or interpret. Self-Explanatory models are a new approach to overcoming this challenge, generating explanations in human-readable languages besides task objectives like answering questions. The main focus of this thesis is the explainability of NLP tasks, as well as how attention methods can help enhance performance. Three different attention modules are proposed, SimpleAttention, CrossSelfAttention, and CrossModality. It also includes a new dataset transformation method called Two-Documents that converts every dataset into two separate documents required by the …

Identification Of Factors Contributing To Traffic Crashes By Analysis Of Text Narratives, Cristian D. Arteaga-Sanchez

UNLV Theses, Dissertations, Professional Papers, and Capstones

The fatalities, injuries, and property damage that result from traffic crashes impose a significant burden on society. Current research and practice in traffic safety rely on analysis of quantitative data from crash reports to understand crash severity contributors and develop countermeasures. Despite advances from this effort, quantitative crash data suffers from drawbacks, such as the limited ability to capture all the information relevant to the crashes and the potential errors introduced during data collection. Crash narratives can help address these limitations, as they contain detailed descriptions of the context and sequence of events of the crash. However, the unstructured nature …

Hard-Real-Time Computing Performance In A Cloud Environment, Alvin Cornelius Murphy

Engineering Management & Systems Engineering Theses & Dissertations

The United States Department of Defense (DoD) is rapidly working with DoD Services to move from multi-year (e.g., 7-10) traditional acquisition programs to a commercial industrybased approach for software development. While commercial technologies and approaches provide an opportunity for rapid fielding of mission capabilities to pace threats, the suitability of commercial technologies to meet hard-real-time requirements within a surface combat system is unclear. This research establishes technical data to validate the effectiveness and suitability of current commercial technologies to meet the hard-real-time demands of a DoD combat management system. (Moreland Jr., 2013) conducted similar research; however, microservices, containers, and container …

Gate-Controlled Quantum Dots In Two-Dimensional Tungsten Diselenide And One-Dimensional Tellurium Nanowires, Shiva Davari Dolatabadi

Graduate Theses and Dissertations

This work focuses on the investigation of gate-defined quantum dots in two-dimensional transition metal dichalcogenide tungsten diselenide (WSe2) as a means to unravel mesoscopic physical phenomena such as valley-contrasting physics in WSe2 flakes and its potential application as qubit, as well as realizing gate-controlled quantum dots based on elementaltellurium nanostructures which may unlock the topological nature of the host material carriers such as Weyl states in tellurium nanowires.The fabrication and characterization of gate-defined hole quantum dots in monolayer and bilayer WSe2 are reported. The gate electrodes in the device design are located above and below the WSe2 nanoflakes to accumulate …

Design And Comparison Of Asynchronous Fft Implementations, Julie Bigot

Graduate Theses and Dissertations

Fast Fourier Transform (FFT) is a widely used digital signal processing technology in a large variety of applications. For battery-powered embedded systems incorporating FFT, its physical implementation is constrained by strict power consumption, especially during idle periods. Compared to the prevailing clocked synchronous counterpart, quasi-delay insensitive asynchronous circuits offer a series of advantages including flexible timing requirement and lower leakage power, making them ideal choices for these systems. In this thesis work, various FFT configurations were implemented in the low-power Multi-Threshold NULL Convention Logic (MTNCL) paradigm. Analysis illustrates the area and power consumption trends along the changing of the number …

Data-Driven Deep Learning-Based Analysis On Thz Imaging, Haoyan Liu

Graduate Theses and Dissertations

Breast cancer affects about 12.5% of women population in the United States. Surgical operations are often needed post diagnosis. Breast conserving surgery can help remove malignant tumors while maximizing the remaining healthy tissues. Due to lacking effective real-time tumor analysis tools and a unified operation standard, re-excision rate could be higher than 30% among breast conserving surgery patients. This results in significant physical, physiological, and financial burdens to those patients. This work designs deep learning-based segmentation algorithms that detect tissue type in excised tissues using pulsed THz technology. This work evaluates the algorithms for tissue type classification task among freshly …

Hierarchical Structure And Material Integration For Electrocatalytic Co2 Reduction, Hamed Mehrabi

Graduate Theses and Dissertations

CO2 released by the combustion of fossil fuels is driving significant changes to the earth’sclimate. The natural cycle for removing CO2 from the atmosphere, namely photosynthesis, cannot keep up with the rate at which it is being added. Developing engineering approaches to remove CO2 from the atmosphere is becoming essential to reduce these effects. Removal leads to further issues of carbon sequestration and favorable CO2 reuse strategies, including the electrochemical transformation of recovered CO2 to useful products such as fuels and materials. Copper is an important electrocatalyst for the CO2 reduction reaction (CO2RR) because of its unique capability for producing …

Surface-Driven Instabilities At Oil-Water Interfaces, Anelisse Claros Mendieta

Graduate Theses and Dissertations

Fluid-fluid interactions are such a wide area and can be observed in different scenarios such as geothermal systems, waterflooding of reservoirs, oil recovery, and water treatment processes. This thesis aims to deepen the understanding of fluid-fluid interactions which include Marangoni flows, charge related instabilities, and surface activity. This thesis studied the interactions of micrometer-sized droplets of an oil (toluene) with surfactant Di-(2-ethylhexyl) phosphoric acid (DEHPA) in the aqueous phase. One of the main goals is to understand several surface-driven instabilities and how those can be manipulated for future applications.Furthermore, this thesis aims to use these oil-surfactant droplets as a medium …

Sustainability And Health Impacts Of Pulse Crops In The United States Using Life Cycle Assessment, Prathamesh A. Bandekar

Graduate Theses and Dissertations

Environmental sustainability and human health impact of pulses produced and consumed in the United States was assessed using life cycle assessment (LCA). The study included three objectives 1) to estimate environmental impact of current production and consumption practices in the United States using attributional LCA; 2) to estimate environmental and human health impact of iso-caloric diets containing varying amounts of pulses using Hybrid-LCA and Combined Nutritional and Environmental-LCA (CONE-LCA); and 3) to estimate environmental impact of increased demand for pulses using consequential LCA. Scope of the study varied for each objective with system boundary encompassing cradle-to-grave activities for objective 1 …

Electrical Modeling For Dynamic Performance Prediction And Optimization Of Mcpms Layout, Quang Minh Le

Graduate Theses and Dissertations

In recent years, the fast development of Multichip Power Modules (MCPM) packaging and Wide Bandgap (WBG) technology has enabled higher voltage and current ratings, better thermal performance, lower parasitic parameters, and higher mechanical reliability. However, the design of the MCPM layout is a multidisciplinary problem leading to many time-consuming analyses and tedious design processes. Because of these challenges, the design automation tool for MCPM layout has become an emerging research area and gained much attention from the power electronics community. The two critical objectives of a design automation tool for MCPM layout are fast and accurate models for design insights …

Characterization Of Losses In Superconducting Radio-Frequency Cavities By Combined Temperature And Magnetic Field Mapping, Ishwari Prasad Parajuli

Physics Theses & Dissertations

Superconducting radio-frequency (SRF) cavities are one of the fundamental building blocks of modern particle accelerators. To achieve the highest quality factors (10¹⁰-10¹¹), SRF cavities are operated at liquid helium temperatures. Magnetic flux trapped on the surface of SRF cavities during cool-down below the critical temperature is one of the leading sources of residual RF losses. Instruments capable of detecting the distribution of trapped flux on the cavity surface are in high demand in order to better understand its relation to the cavity material, surface treatments and environmental conditions. We have designed, developed, and commissioned two novel …

Numerical Simulation Of Electroosmotic Flow Of Viscoelastic Fluid In Microchannel, Jianyu Ji

Mechanical & Aerospace Engineering Theses & Dissertations

Electroosmotic flow (EOF) has been widely used in various biochemical microfluidic applications, many of which often involve the use of viscoelastic non-Newtonian fluids. Due to the existence of the elastic effect, the viscoelastic EOF develops into chaotic flow under extremely low Reynolds numbers, which is known as elastic turbulence. The mechanism of elastic turbulence in electroosmotic flow remains unclear. Numerical simulation plays an important role in understanding the mechanisms of elastic turbulence. This dissertation is aimed to study the EOF of viscoelastic fluids in constriction microchannels under various direct current (DC) and alternating current (AC) electric fields. First, the EOF …

Investigation Of Gaas Double Heterostructures For Photonic Heat Engines, Nathan Giannini-Hutchin

Optical Science and Engineering ETDs

The creation of a laser cooled semiconductor device has been a long sought achievement. GaAs-based devices have emerged as a promising candidate for the realization of this goal. Efforts to improve the efficiency of such devices have enabled the material to exhibit external quantum efficiencies (EQE, a measure of the probability that an excitation leads to the emission of a photon) of 99.5\%. Despite this impressive feat, a laser coolable device remains elusive.

To investigate the obstacles to such a device, the material characteristics of GaAs-based double heterostructures (DHS) are theoretically and experimentally examined. Through this study, a GaAs $\vert$ …

Achieving Safe Use Of Advanced Materials In Drinking Water Through Novel Nano Analytics And Enabling Electrification Using Green Catalyst, Kenneth Ray Flores

Open Access Theses & Dissertations

The accumulation of engineered nanomaterials (ENMs) in environmental sectors will continue to increase as more applications are discovered for their unique properties and characteristics. Additionally, the presence of nanomaterials in the environment becomes exacerbated as more consumer products containing nanoparticles are approved for use. It is debated whether the toxic effects of nanoparticles stem from the particles themselves, ionic species, or formation of secondary particles. Therefore, understanding the behavior of nanoparticles in the environment becomes key to discerning the toxicological effects of nanoparticles. Many advancements have been made with ICP-MS to understand the behavior of nanoparticles in the environmental systems, …

Nano-Engineered Soft Magnets: Potential Application In Water Treatment, Hyperthermia And Molecular (Organic) Magnets, Yohannes Weldemariam Getahun

Open Access Theses & Dissertations

Scrutinizing the remarkable and tunable properties of magnetic materials at a nanoscale size "There's Plenty of Room at the Bottom..." Richard Feynman, this study attempts to find sustainable solutions to some of the deteriorating environmental, health, and energy problems the world is encountering. Due to their simple preparation, surface adaptability, and tunable magnetic and optical properties, magnetic nanoparticles have been extensively investigated in water treatment, cancer therapy, data storage, and more. However, relying on non-reusable and chemical-based treatment agents in water, complex and costly cancer treatment procedures and molecular magnets that operate far below room temperature limited those attempts from …

The Qualification Of Sealability And Creep Relaxation Of Additively Manufactured Zytel Gaskets For Pem Fuel Cells, Robert Lazarin

Open Access Theses & Dissertations

The purpose of this thesis is to study the feasibility of low-cost additive manufacturing of gaskets for proton exchange membrane fuel cells exposed to extreme temperature conditions ranging from -55°C to 100°C. With the growing popularity and decreasing costs of additive manufacturing technologies, specifically Material Extrusion (ME), research is being conducted to determine the feasibility of ME components. Thermally cycled PEMFCs may exhibit accelerated gasket deterioration, therefore, the mechanical stability of material extruded gaskets following a harsh thermal cycle must be assessed. The feasibility of the material extruded gaskets will be proven by manufacturing optimization and mechanical testing. The target …

The Living Breakwaters Pdr Efforts Econcrete Resource Analysis, Guianina Ferrari, Shervon Stephens, Calvin O. Walters Jr.

Publications and Research

On October 29, 2012, Superstorm Sandy impacted 443,000 people and caused nearly $19 billion (about $58 per person in the US) worth of damage within New York City. As part of the New York City infrastructure reparation plan, the Living Breakwaters project in Tottenville addressed coastal resilience, allocating $100M of public funds to a series of artificial breakwaters by the southwest coast of Staten Island. Each breakwater is constructed and designed to mitigate water flow in storm events. ECOncrete, a primary element of the breakwater, is a specialty cast cementitious product that is marine organism-friendly that encourages biocalcification and photosynthesis. …

Raman Scattering Measurements And Analyses Of Gan Thin Films Grown On Zno Substrates By Metalorganic Chemical Vapor Deposition, Zane Mcdaniel, Zhe Chuan Feng, Kevin Stokes

Symposium of Student Scholars

Metalorganic chemical vapor deposition (MOCVD) is a popularly used method of growing thin films of GaN on ZnO (GZ) substrates, which pair well due to their structural and characteristic similarities. In this research, optical characterization of the surface quality of GZ sample films is measured by analyzing Raman scattering (RS) using a Renishaw inVia spectrometer fitted with a 532nm laser. Samples were grown in an improved double injection block rotating disc reactor. Multiple samples' spectra show broad peaks that correspond with the E2 (high) and A1 (LO) branches of GaN, and nicely fitted curves are observed for the characteristic E2 …

2022 Fall Engr333 Seminar Presentation, Jordan Tuter, Aidan Bakker, Samuel Hoover, Jessica Camp

ENGR 333

File for student presentation on Carbon Neutrality for Calvin University, given by students in the Fall 2022 class of ENGR333.

A Pipeline To Generate Deep Learning Surrogates Of Genome-Scale Metabolic Models, Achilles Rasquinha

School of Computing: Dissertations, Theses, and Student Research

Genome-Scale Metabolic Models (GEMMs) are powerful reconstructions of biological systems that help metabolic engineers understand and predict growth conditions subjected to various environmental factors around the cellular metabolism of an organism in observation, purely in silico. Applications of metabolic engineering range from perturbation analysis and drug-target discovery to predicting growth rates of biotechnologically important metabolites and reaction objectives within dierent single-cell and multi-cellular organism types. GEMMs use mathematical frameworks for quantitative estimations of flux distributions within metabolic networks. The reasons behind why an organism activates, stuns, or fluctuates between alternative pathways for growth and survival, however, remain relatively unknown. GEMMs …

Active Attestation Of Embedded Systems, Mark M. Stephenson, Patrick A. Reber, Patrick J. Sweeney, Scott R. Graham

AFIT Patents

An active attestation apparatus verifies at runtime the integrity of untrusted machine code of an embedded system residing in a memory device while it is being run/used with while slowing the processing time less than other methods. The apparatus uses an integrated circuit chip containing a microcontroller and a reprogrammable logic device, such as a field programmable gate array (FPGA), to implement software attestation at runtime and in less time than is typically possible with comparable attestation approaches, while not requiring any halt of the processor in the microcontroller. The reprogrammable logic device includes functionality to load an encrypted version …

Key Technologies And Equipment Of Quickly And Safely Building Life Support And Rescue Channel In Mine Disaster, Tian Hongliang, Zou Zujie, Hao Shijun, Cao Ming, Zhou Guanghua, Huang Yong, Gu Hairong, Wang Lei

Coal Geology & Exploration

In case that persons are trapped underground as a result of shaft and roadway damage due to a major disaster accident in a mine, the most effective way of rescue is to construct the rescue channel in a safely and efficient manner. The rescue channel is divided into the underground and ground types. Building a large diameter rescue channel through the collapsed section is the most direct way if underground construction conditions are available. However, if no underground construction conditions are available or it is prone to secondary disasters, it is necessary to drill small diameter rescue holes on the …

Key Technologies Of Surface Efficient Life Support Hole Forming For Mine Rescue, Zhang Biao, Kang Yuguo, Huang Yong, Zhang Ming, Zhou Guang, Ren Yingju, Liu Jianlin, Gao Ke, Zhao Yan

Coal Geology & Exploration

The surface life support hole, as the support channel for the trapped people underground, is one of the important ground emergency rescue schemes for the situation with some people trapped underground due to mine accidents. Under the complex conditions of the rescue area, including easy collapse, easy leakage, large water inflow and inclined formation, the single hole forming process has the problems such as poor ground adaptability matching, low comprehensive drilling efficiency and difficult roadway penetration, which cannot meet the requirements of rescue. In order to form an efficient drilling technology system for life support holes and improve the response …

Research Progress Of Lifting Equipment For Large-Diameter Borehole Rescue, Gu Hairong, Shan Zenghai, Wang Longpeng, Shao Tao, Zou Zujie, Gao Ziyu

Coal Geology & Exploration

Rescue through large-diameter relief well is an efficient method of mine emergency rescue. The lifting equipment of large-diameter relief well is used to lift the trapped personnel safely and reliably to the surface through the large-diameter relief well. It is the key equipment in the rescue system of large-diameter relief well. With the rescue technology of large-diameter relief well gradually recognized in the industry, the lifting equipment of large-diameter relief well has developed considerably, forming the fixed and mobile types of lifting equipment and multiple technical routes. Besides, important progress has been made in the research on the lifting equipment …

Research And Application Of Synchronous Self-Balancing Feed System For Rescue Truck-Mounted Drilling Rig, Zou Zujie, Tian Hongliang, Liu Qingxiu, Chang Jianghua, Liu Qi, Zhu Guodong

Coal Geology & Exploration

Truck-mounted drilling rig is the core equipment of ground drilling rescue in mine accidents, and it has played an important role in all the successful rescues at home and abroad. However, the feed system, as the main actuator of the truck-mounted drilling rig, exposes the problems of restricted passability of the whole machine due to the long working stroke, difficult maintenance of the positioning wheel train, poor movement synchronization of the double cylinder, guide rail wearing caused by the partial load of power head, and the delay of pulling force displayed by the hydraulic gauge during its service. ZMK5550TZJF50/120 rescue …

Main Influencing Factors For Regional Pre-Grouting Technology Of Water Hazard Treatment In Coal Seam Floor And Efficient Hole Arrangement, Hu Weiyue, Zhao Chunhu, Lyu Hanjiang

Coal Geology & Exploration

Regional advance grouting transformation and reinforcement of water conducting formation and aquifer is the main technical means to prevent and control the karst water hazards in the coal seam floor of North China type coalfields. Herein, analysis was conducted for the general application mode of the regional advance grouting transformation and reinforcement for water hazard treatment in the thin and thick limestone layers in the coal seam floor based on the basic mine hydrogeological principle of the application of regional advance grouting transformation technology. In the analysis, consideration was given to the hydrogeological structure of the coal seam floor, the …

Key Pretreatment Technologies For Coalbed Gas Bioengineering And Review On Their Mechanism Of Action, Bao Yuan, Chang Jianing, Liu Xiangrong, Xia Daping, Wang Yaya

Coal Geology & Exploration

Coalbed gas bioengineering (CGB) is a new technology for the purpose of realizing the clean utilization of coal resources and the enhanced recovery of coalbed gas. To explore the key characteristics of the pretreatment technologies of CGB, hydrocarbon generation potential and its mechanism of action, conclusion and summary was made for various pretreatment technologies herein. Meanwhile, the pretreatment technologies were divided into three types according to the action mode of coal (organic matter) and bacteria (microorganism): microflora optimization and improvement, coal dissolution and oxidation, and biological stimulation and synergy. By comparing the capability of coal to generate methane through microbial …

Occurrence Characteristics And Ecological Risk Assessment Of Heavy Metals In Fly Ash Of Ningdong Energy Chemical Industry Base, Zhang Zhiguo, Tan Yuning, Hu Youbiao, Zheng Yonghong, Chen Denghong, Cai Weiqing, Li Yating, Lu Jiangwei

Coal Geology & Exploration

In order to expand the resource utilization of fly ash, research was conducted based on the fly ash of Yuanyang Lake Power Plant in the Ningdong Energy Chemical Industry Base. Specifically, the physical and chemical properties of fly ash were characterized and analyzed by means of scanning electron microscope, energy spectrum analysis and X-ray diffraction. Besides, the total amount, effective state and content in different forms of Pb, Cr, Ni, Cu, Cd and As in fly ash were determined through acid digestion, DTPA extraction and 5-step Tessier sequential extraction. In addition, the ecological risk of heavy metals in fly ash …

Heat Conduction Performance And Transfer Mechanism Of Sand-Barite Powder Backfill Materials, Jia Hailiang, Zhu Zixian, Zhou Yang, Sun Qiang

Coal Geology & Exploration

The ground source heat pump of buried pipeline is a major form of shallow thermal energy utilization, and the thermophysical properties of backfill materials, especially the thermal conductivity, are the key factors affecting the heat transfer efficiency of the heat pump system. In this paper, the variation law of thermal conductivity of the sand-barite powder samples at different barite powder mixing ratio (volume fraction) and saturation was studied. The mechanism of improving the thermal conductivity of backfill materials with barite powder was revealed based on the macroscopic and microscopic experiments such as stereoscope and nuclear magnetic resonance analysis. In addition, …