Engineering Commons^™

Etdsuite: A Toolkit To Mine Electronic Theses And Dissertations To Enrich Scholarly Big Data Using Natural Language Processing And Computer Vision, Muntabir Hasan Choudhury

Computer Science Theses & Dissertations

In the past decades, there has been a growing interest in mining scientific documents to obtain domain knowledge automatically. One of the understudied types of scientific documents is Electronic Theses and Dissertations (ETDs), as ETDs have distinct features compared with conference proceedings and journal articles. ETDs usually serve as partial requirements of academic degrees for students pursuing higher education. They are book-length documents (i.e., 100 – 400 pages long), and the topics may shift across chapters, exhibit the significant contribution of a student’s research over the entire degree pursuing period, and have unique metadata schema and page layouts. However, the …

An Interaction Between Mental Integration And Levels Of Automation: An Analytic Approach Applying Systems Factorial Technology, Shelby Kate Scarbrough Long

Psychology Theses & Dissertations

Automation has become nearly ubiquitous in modern society, supporting human performance in personal and professional tasks. Recent works have begun to focus on human-automation performance in speeded perceptual-cognitive tasks using workload capacity analysis, a novel mathematical analysis to measure efficiency of a human-automation team. The present dissertation examined how level of automation and demand for mental integration of information influence human-automation efficiency. Participants performed a multi-element probabilistic decision task with or without the assistance of an automated aid where level of automation and task demand were manipulated. Experiment 1 employed a mixed design with Automation (present vs. absent) and Task …

Simulating The Compound Impacts Of Climate Change And Sea-Level Rise On Coastal Shallow Groundwater Using An Integrated Surface-Subsurface Hydrologic Model, Zhaoyi Cai

Civil & Environmental Engineering Theses & Dissertations

As climate change intensifies and sea levels rise, coastal aquifers become increasingly vulnerable to interacting oceanic and terrestrial processes. This dissertation examines the combined impacts of climate change and sea-level rise (SLR) on coastal shallow groundwater using an integrated surface-subsurface hydrologic model, focusing on the low-lying Little Creek watershed (LCW) in Norfolk, Virginia. The SWAT-MODFLOW model, a coupled system, unifies land surface, streamflow, and groundwater processes, providing a comprehensive framework for watershed-aquifer analysis. Model parameters were derived from U.S. Geological Survey datasets, relevant literature, station records, and technical reports, followed by meticulous calibration. The validated model first simulated baseline groundwater …

Intrinsic Manipulation Of Microstructure And Strength Of Ice-Templated Lithium Titanate, Rohan Parai

Mechanical & Aerospace Engineering Theses & Dissertations

This dissertation focuses on developing a fabrication landscape first time ever for directionally porous lithium titanate (LTO) materials using ice-templating technique. Ice-templating, a promising fabrication technique for porous ceramics, enables the formation of sintered structures with anisotropic pores that are aligned to improve mechanical stability of materials.

The work presented in this dissertation addresses advancements in tuning the porosity, strength, and microstructural characteristics of ice-templated LTO materials through adjustments of intrinsic variables, including sucrose as a water-soluble additive, variations in freezing front velocity, solute concentration, and solid loading. First, this study demonstrated that adding sucrose in LTO suspensions increased the …

Computer Based Modeling For Small E-Vtol Propeller Performance, Ege Konuk

Mechanical & Aerospace Engineering Theses & Dissertations

The emerging field of urban air mobility (UAM) offers a novel transportation method for civil, commercial, and military applications. Vertical take-off and landing (VTOL) configurations present challenges for performance prediction during crucial flight operations. An advanced computational framework for predicting propeller performance in electric vertical takeoff and landing (eVTOL) aircraft during transition flight is essential for future concept designs. This research extends the Blade Element Momentum Theory (BEMT) to model propeller behavior at high incidence angles, crucial for eVTOL operation.

The study begins with a review of tilt-wing/rotor configurations for eVTOLs and tackles the complex aerodynamic phenomena associated with rotors …

Comprehensive Study Of Energy Capturing, Conversion, And Transportation Behaviors In A Piezoelectric Vibration Energy Harvesting System, Bingqi Zhao

Mechanical & Aerospace Engineering Theses & Dissertations

Piezoelectric vibration energy harvester (PEH) is one of the hottest research areas to address renewable energy issues with over 10,000 journal articles published in the last two decades. However, several critical issues, such as the proof mass effects, electrical impedance, mechanical resonance, and energy charging processing, remain open. This dissertation presents a comprehensive study addressing the above issues.

To obtain reliable results, a professional quality flextensional PEH (FPEH) and multiple comprehensive experimental methods were developed, and ANSYS FEM modelling was used. Study of the proof mass effect indicated that the generated voltage linearly increased with the weight ratio of the …

Suppression Of Dynamic Aeroelastic Response Of A Semispan Wing Using Traditional And Distributed Sensing, James Ramey

Mechanical & Aerospace Engineering Theses & Dissertations

Characterization and management of aeroelastic effects are a vital part of aircraft design. Mitigation of these effects often includes control systems to suppress the vibrations. Control systems are constantly being developed and improved, with one such avenue of development being new sensing systems that can increase the information fed into the controller. Fiber Optic Strain Sensing (FOSS) technology is one such system that utilizes Fiber Bragg Gratings (FBGs) on a fiber optic cable to sense the strain on structural elements. This system has promise as a high-density feedback device, and the maturation of the technology has allowed assessment of its …

Verification And Validation Of Modeling Of Fluid–Solid Interaction In Explosion-Resistant Designs Using Material Point Method, Mohammed H. Saffarini, Zhen Chen, Ahmed Elbelbisi, Hani Salim, Kyle A. Perry, Andrew L. Bowman, Stephen D. Robert

Mining Engineering Faculty Research & Creative Works

Verifying and validating explosion-resistant design models are challenging tasks due to the difficulties in accurately capturing the failure evolution within a setup influenced by the combined effects of fluid–solid interactions (FSI), blast waves, fragmentation, and impact. Curtain wall system, as a key structural component, is widely used in various types of buildings for its aesthetic appeal and weather protection. Hence, optimizing the explosion-resistance of such systems is necessary to improve building safety. In this work, we develop computational procedures that can be used to enhance the design of blast-resistant structures. This paper focuses on studying a representative component (e.g., window …

Adaptive Control And Estimation Of The Center Of Mass Of A 5-Degree-Of-Freedom Spacecraft Testbed, Pol Fontdegloria Balaguer

Doctoral Dissertations and Master's Theses

In space applications, on-ground experimentation is an essential step in control algorithm validation before real mission application. However, on-ground conditions greatly differ from space ones, where satellites operate under extremely low gravity and friction conditions. A common way to simulate these conditions is with air-bearing-based testbeds. These testbeds reduce friction significantly to almost space-like conditions. Air-bearing technology can provide virtually frictionless translational and rotational motion. However, when frictionless rotational motion is achieved, the testbed becomes highly sensible gravity torque. This external torque is produced by the offset between the predetermined geometrical center of rotation (CoR) and the center …

Effect Of Storage Time And Temperature On Aggregation Of Alzheimer's Disease Amyloid-Β Protein, Amy Veihdeffer

Theses and Dissertations

Amyloid-β protein (Aβ) is widely studied due to its key role in Alzheimer’s disease (AD) pathology. One characteristic of patients suffering from AD is the deposition of amyloid plaques comprised of Aβ aggregates, which are associated with synapse damage. Thus, studying Aβ aggregation and aggregation inhibition may provide pathological and therapeutic insights. Aggregation of Aβ is a nucleation dependent process that may be influenced by the presence of pre-formed Aβ aggregate seeds that can facilitate formation of protein aggregates. These seeds may appear during preparation or storage of monomer, posing impact on experiments that study the aggregation process and the …

Evaluation Of Settlement In Poorly Graded Sand With Gravel Under Strain-Controlled Cyclic Triaxial And Dynamic Centrifuge Model Testing Conditions, Elise Jones

Theses and Dissertations

This research evaluates the dynamic behavior and volume change of sand with gravel subjected to cyclic loading. Historically, research on the dynamic behavior of cohesionless soils has primarily focused on the study of liquefaction due to its known implications on soil shear strength loss. Gravelly soil is generally assumed to be less susceptible to liquefaction since its large particle size facilitates drainage during cyclic loading. Gravel’s particle size also makes it difficult to test using standard cyclic shearing laboratory equipment. Thus, there is a lack of widespread research and predictive methods for the dynamic behavior of gravelly soil. Determining the …

Interpretation Of Surface Roughness Of Stainless Steel 316l In Laser Powder Bed Fusion Additive Manufacturing, Tianyu Zhang

Theses and Dissertations

Laser Powder Bed Fusion (L-PBF), a widely used metal additive manufacturing (AM) method, is emerging as a key technology in the modern manufacturing industry. Its applications span across aerospace, transportation, energy, and biomedical industries, aiming to maximize product functionality, quality, and manufacturing efficiency.

Surface roughness, an important measure of product quality, impacts geometrical tolerances and plays a critical role in mechanical and functional properties. Although post-process techniques such as machining, shot peening, and chemical processing can be used to refine surfaces, internal surfaces in complex geometries remain difficult to treat, limiting part performance due to undesired surface features. The …

Leveraging The Usage Of Blockchain Towards Trust-Dominated Manufacturing Systems, Philip Joseph Samaha

Theses and Dissertations

Smart Manufacturing has elevated manufacturing processes, transitioning from automated systems to autonomous ones. This evolution has heightened the significance of data within manufacturing facilities. The role of data has evolved from solely monitoring processes to both monitoring and extracting insights from these processes, facilitating precise control. In this context, the data infrastructure plays a critical role, encompassing both internal data circulating within the facility—such as information exchanged between controllers and actuators—and external data transmitted to and from outside entities. When the factory's cyber infrastructure is connected to the internet, security concerns escalate significantly, amplifying associated risks. Therefore, the integration of …

Mechanics Based Characterization Of Elastic Metamaterials, Mamdudur Rahman

Theses and Dissertations

In bandgap engineering there is a shortage of systematic design approach which enables one to select design variables to achieve bandgap in desired frequency range. Tools that can address this can open new areas of interest, especially since phononic crystals with low frequency bandgaps have multitude of applications in attenuation of structural vibration. Furthermore, mechanics-based characterization of phononic crystals had not seen much progress in the recent years while a lot of applied research had been conducted on phononic materials with material phase periodicity and other factors taken into consideration. This work aims to propose a systematic characterization approach of …

Neutrosophic Approach To Water Quality Assessment: A Case Study Of Gomati River, The Largest River In Tripura, India, Ajoy Kanti Das, Nandini Gupta, Carlos Granados, Rakhal Das, Suman Das

Neutrosophic Systems with Applications

This study addresses the complexity of assessing river water quality, a multifaceted process influenced by numerous water quality parameters (WQPs) characterized by inherent uncertainties and diverse judgment information from decision-makers. These uncertainties and diverse judgment information can be effectively represented and simulated using Neutrosophic sets. In this study, we propose an effective water pollution rating system, the Neutrosophic water quality index (NWQI), to derive a water pollution score (NWQI-score) for rating water pollution levels. We demonstrate the application of our methodology through an assessment of water quality indices for rating pollution in the Gomati River, the largest river in Tripura, …

Evaluation Of Renewable Energy Sources For A Sustainable Future: A Multi-Criteria Decision-Making Approach, Mai Mohamed, Asmaa Elsayed

Neutrosophic Systems with Applications

The urgent global challenges of climate change, energy security, and environmental degradation highlight the need for sustainable energy solutions. Renewable energy sources (RES) present a viable pathway towards sustainability by mitigating greenhouse gas emissions, reducing reliance on fossil fuels, and fostering economic resilience. Purpose: The purpose of this paper is to propose an advanced Multi-Criteria Decision-Making (MCDM) approach to evaluate various RES by integrating environmental, economic, technological, social acceptance, and resource availability criteria, to identify the most suitable RES for sustainable energy solutions. Methodology: The study employs a hybrid method combining Type-2 Neutrosophic Numbers (T2NN) with LOPCOW (Logarithmic Percentage Change …

In Situ Assembly Enabling Adhesive-Free Bonding Of Large Area Electronic Sensors To Concrete For Structural Health Monitoring, Emmanuel Ogunniyi, Han Liu, Austin Downey, Simon Laflamme, Caroline Bennett, William Collins, Hongki Jo, Paul Ziehl

Faculty Publications

Cracks developed in concrete infrastructure are one of the primary mechanisms that degrade their structural integrity, which may result in structural failures. Previous research on soft elastomeric capacitors (SEC) has shown their viability for structural health monitoring of structural materials, including concrete, steel, and fiberglass composites. The SEC, or its derivative version with a corrugated geometry termed corrugated SEC or cSEC, is a parallel plate capacitor. Prior work demonstrated that it was possible to directly paint the electrode interfacing with the structural material onto the structure and adhere the rest of the pre-fabricated sensor onto the wet interface, thereby eliminating …

Importance Sampling To Learn Vasopressor Dosage To Optimize Patient Mortality In An Interpretable Manner, Anshul Rastogi

Holster Scholar Projects

Sepsis is a life-threatening organ dysfunction resulting from an improperly compensated bodily response to infection. There is a high urgency among clinicians to develop a set of real-time explainable treatment guidelines and tools to address the high mortality rate of sepsis patients. We present a reinforcement learning approach for vasopressor drug dosage in intensive care unit sepsis patients to achieve a better-than-expert treatment policy. We preserved interpretability with a prototype learning layer and learn actions in an off-policy manner with importance sampling. We evaluated our design on the MIMIC-IV deidentified electronic health record dataset with an 80%-20% training-validation split for …

Overcoming Contamination Obstacles In Additive Manufacturing A Monolithic Propulsion Structure For The Sunrise Mission, Holly Walen, Emma Brown, Robert Fowler

Space Dynamics Laboratory Publications

The SunRISE propulsion system utilizes an additively manufactured monolithic structure containing a main tank, plenum, and six thrusters. The complex design geometry and novel manufacturing approach of this structure lends itself to several problems, primarily related to the consistent fabrication of the thruster channels. Standard cleaning methods for stereolithography printing were inadequate to meet program requirements for this structure, leading to the development of a rigorous cleaning approach and intermediate characterization of the thruster throughput during the manufacturing process. In this paper, we present the cleaning and characterization approach that lent to the successful manufacturing of the SunRISE propulsion structure.

A Study On The Polarity Of Generalized Neutrosophic Ideals In Bck-Algebra, Bavanari Satyanarayana, Shake Baji

Neutrosophic Systems with Applications

In this study, we apply k-polar generalized neutrosophic logic to the ideal of BCK-algebra and consequently introduce the notion of a k-polar generalized neutrosophic ideal in BCK-algebra with an example. We provide conditions for a k-polar generalized neutrosophic set to be a k-polar generalized neutrosophic ideal. We prove that every k-polar generalized neutrosophic ideal is a k-polar generalized neutrosophic subalgebra, but the converse is not true, which can be illustrated with an example. Furthermore, we prove that a k-polar generalized neutrosophic set is a k-polar generalized neutrosophic ideal if and only if its corresponding cut sets are ideals of the …

Analysis Of Shock Absorption By Spring-Assisted Crutch Tips, Noah Hirschegger, Daegan Caime, Mohamed Atta

Senior Theses

Angel Consulting was originally created to address the problem of excessive wear and tear on the joints of individuals who use crutches for long periods of time. This company has sought to alleviate these issues with a proprietary spring-assisted crutch tip, which reduces the impact of crutch use and will hopefully be able to assist people in alleviating joint damage and discomfort. The team's main purpose is to determine an optimal metric for both marketability and effectiveness and to test the prototype design to ensure the validity of assistance for people who require chronic crutch use. To do this, we …

Devices And Dining: A Cross-Cultural Analysis Of Mobile Device Use In Italian And American Restaurants, O'Malley Jenkins

Senior Theses

The field of technology ethics has seen increasing growth and interest over the years. Many have begun to consider the impacts of technology’s use and whether it is being employed in a healthy manner by users. However, there has been limited investigation into whether the ways in which technology use varies across cultures. This study begins to address this gap by researching Italian and American device usage in fast food settings. Non-participant naturalistic observations were used to record data for 89 Italian and 88 American customers of fast food restaurants. Analysis of the collected data indicates that Americans use their …

A Comprehensive Study On Long-Term Durability Of Protective Epoxy Coatings For Electrified Roadways, Md Tareq Hassan, Samiul Alam, Juhyeong Lee

Mechanical and Aerospace Engineering Faculty Publications

Underground wireless power transmission (WPT) systems are susceptible to environmental threats such as high temperatures, water ingress, and mechanical impact from above-ground objects. Typical WPT systems electronics are safeguarded with civil-grade epoxy coating, thus it is imperative to assess the coating's durability in these extreme conditions. Among various environmental threats, this study is primarily focused on both experimental and numerical investigations on long-term water diffusion characteristics of civil-grade epoxy materials at various temperatures. A series of water diffusion tests were performed on the specimens made from two commercially available electronics casting epoxy materials at room (23°C) and high (50°C) temperatures. …

Brushbuds: Toothbrushing Tracking Using Earphone Imus, Qiang Yang, Yang Liu, Jake Stuchbury-Wass, Kayla-Jade Butkow, Dong Ma, Cecilia Mascolo

Research Collection School Of Computing and Information Systems

Inadequate toothbrushing habits are a leading cause of oral health problems such as tooth decay. Many individuals are uncertain if they are brushing effectively or over-focusing on specific areas. While high-end electric toothbrushes can address these concerns, manual toothbrushes remain widely used due to their simplicity and affordability. In this paper, we introduce BrushBuds, an earphone-based toothbrushing monitoring system aimed at tracking brushing areas, which leverages the ubiquitous presence of earphones to enhance manual toothbrushing. BrushBuds utilizes Inertial Measurement Units (IMUs) in earphones to detect subtle head movements incurred by toothbrushing. By capturing distinct motion patterns specific to brushing for …

Constrained Assortment Optimization Under The Cross-Nested Logit Model, Cuong Le, Tien Mai

Research Collection School Of Computing and Information Systems

We study the assortment optimization problem under general linear constraints, where the customer choice behavior is captured by the cross-nested logit model. In this problem, there is a set of products organized into multiple subsets (or nests), where each product can belong to more than one nest. The aim is to find an assortment to offer to customers so that the expected revenue is maximized. We show that, under the cross-nested logit model, the unconstrained assortment problem is NP-hard even when there are only two nests, and the problem is generally NP-hard to approximate to any constant factors. To tackle …

Ocapo: Fine-Grained Occupancy-Aware, Empirically-Driven Pdc Control In Open-Plan, Shared Workspaces, Ravi Anuradha, Dulaj Sanjaya Weerakoon, Archan Misra

Research Collection School Of Computing and Information Systems

Passive Displacement Cooling (PDC) is a relatively recent technology gaining attention as a means of significantly reducing building energy consumption overheads, especially in tropical climates. PDC eliminates the use of mechanical fans, instead using chilled-water heat exchangers to perform convective cooling. In this paper, we identify and characterize the impact of several key parameters affecting occupant comfort in a 1000m2 open-floor area (consisting of multiple zones) of a ZEB (Zero Energy Building) deployed with PDC units and tackle the problem of setting the temperature setpoint of the PDC units to assure occupant thermal comfort and yet conserve energy. We tackle …

Investigation Of The Operational Benefits Of Flipped Left Diamond Interchange, Nazmus Salehin Asif,

Theses (2016-Present)

Interchange is an important element to accommodate the critical movement between arterials and freeways. To operate efficiently, innovative interchange designs have been suggested by transportation professionals. Recently, an innovative interchange design called flipped left diamond interchange (FLDI) design has been proposed. That aims to increase capacity and improve efficiency by flipping the left-turn lanes in opposing directions, eliminating conflicts between opposing left-turn movements. So, the signal timing of the left turn movements and through movements are independent which indicates the signal timing of these movements can be determined based on their volume. Due to this independence, any signal timing sequences …

The Accurate Conversion Of Biological Experiments From Cesium Irradiation To X-Ray Irradiation: The Significance, Problems, And The Future Of Experimental Radiation Research, Gretchen Carpenter

Dartmouth College Master’s Theses

Preclinical small animal irradiation studies, once conducted on Cesium irradiators, are increasingly being performed with X-ray-based irradiators. The transition stems from concerns regarding national security risks, making X-ray irradiators which are compact and easy to operate an enticing alternative. However, questions regarding the relative biological effectiveness between the two sources have revealed a lack of adequate dosimetric characterization of X-ray beams, standardized protocol for dose calibration, and thorough understanding of experimental biological parameters. A literature review conducted on orthovoltage irradiators has revealed that there are over 54 different types of beam structures used, a dramatic departure from the one uniform …

Temporal Forecasting Of High-Rate Dynamic Using Physics-Informed Machine Learning And Hardware-Software Co-Design, Puja Chowdhury

Theses and Dissertations

Due to aging, fatigue, corrosion, and even natural disasters; the health of the structure is prone to degradation throughout its service life. The explosively-fast growing efforts on Structural health monitoring (SHM) always try to exploit different aspects of the automation of damage detection, localization, and prognosis tasks. One of the main challenges is the hardware and software co-design to implement the model in real-life situations. On the other hand, the fast-advancing artificial intelligence draws the researchers' attention to adopt different data-driven approaches in this field. This brings other challenges like domain-specific model adaptation, data bias, data scarcity, model validation by …

Characterization Of A Carbon Fiber Based Broadband Microwave Absorber, Ha Tran, Branimir Pejcinovic, Robert Doneker, Kent Thompson, Adithya Ramachandran

Electrical and Computer Engineering Faculty Publications and Presentations

This paper reports the development and characterization of a novel ultra-wideband microwave absorber material (MAM) based on vertically aligned carbon fibers and ferrite beads. This specific material combination and manufacturing process allows MAM design that is thin, lightweight, and broadband. The material is prepared using a flocking process in which its components are electrostatically deposited on top of an adhesive substrate. Distinct material properties of the substrate and materials layers require characterization done with two separated layers. The microwave absorption characteristics are studied first by rectangular waveguide measurements at X and Ku bands that yield complex electric permittivity and magnetic …