Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

University of South Carolina

Discipline
Keyword
Publication Year
Publication
Publication Type
File Type

Articles 1 - 30 of 1946

Full-Text Articles in Engineering

Proposed Charlotte To Atlanta High-Speed Passenger Rail Line: An Economic, Infrastructural, And Developmental Analysis In The Upstate Of South Carolina, Ian C. Macurda, Kimberly Whitehead Apr 2024

Proposed Charlotte To Atlanta High-Speed Passenger Rail Line: An Economic, Infrastructural, And Developmental Analysis In The Upstate Of South Carolina, Ian C. Macurda, Kimberly Whitehead

SC Upstate Research Symposium

This research paper is an in-depth analysis of the high-speed passenger rail line proposed between Charlotte, NC and Atlanta, GA and its impact on the economy, infrastructure, and future development of the Upstate of South Carolina. Currently, passenger rail service between Charlotte and Atlanta is offered on Amtrak at late hours throughout the night on its long-distance passenger rail line The Crescent from New York City, NY to New Orleans, LA. The train is often delayed and is operating at a deficit for Amtrak, like most of their long-distance routes. Traffic on Interstate 85 through the Upstate is another issue …


Detecting Substance Use Disorder Using Social Media Data And Dark Web: Time And Knowledge Aware Study, Usha Lokala, Orchid Chetia Phukan, Triyasha Ghosh Dastidar, Francois Lamy, Raminta Daniulaityte, Amit Sheth Feb 2024

Detecting Substance Use Disorder Using Social Media Data And Dark Web: Time And Knowledge Aware Study, Usha Lokala, Orchid Chetia Phukan, Triyasha Ghosh Dastidar, Francois Lamy, Raminta Daniulaityte, Amit Sheth

Faculty Publications

Opioid and substance misuse is rampant in the United States today, with the phenomenon known as the "opioid crisis". The relationship between substance use and mental health has been extensively studied, with one possible relationship being: substance misuse causes poor mental health. However, the lack of evidence on the relationship has resulted in opioids being largely inaccessible through legal means. This study analyzes the substance use posts on social media with opioids being sold through crypto market listings. We use the Drug Abuse Ontology, state-of-the-art deep learning, and knowledge-aware BERT-based models to generate sentiment and emotion for the social media …


Left Ventricle Function And Post-Transcriptional Events With Exercise Training In Pigs, Stephanie L. Samani, Shayne C. Barlow, Lisa A. Freeburg, Traci L. Jones, Marlee Poole, Mark A. Sarzynski, Michael R. Zile, Tarek Shazly, Francis G. Spinale Feb 2024

Left Ventricle Function And Post-Transcriptional Events With Exercise Training In Pigs, Stephanie L. Samani, Shayne C. Barlow, Lisa A. Freeburg, Traci L. Jones, Marlee Poole, Mark A. Sarzynski, Michael R. Zile, Tarek Shazly, Francis G. Spinale

Faculty Publications

Background

Standardized exercise protocols have been shown to improve overall cardiovascular fitness, but direct effects on left ventricular (LV) function, particularly diastolic function and relation to post-transcriptional molecular pathways (microRNAs (miRs)) are poorly understood. This project tested the central hypothesis that adaptive LV remodeling resulting from a large animal exercise training protocol, would be directly associated with specific miRs responsible for regulating pathways relevant to LV myocardial stiffness and geometry.

Methods and results

Pigs (n = 9; 25 Kg) underwent a 4 week exercise training protocol (10 degrees elevation, 2.5 mph, 10 min, 5 days/week) whereby LV chamber stiffness (KC) …


Tutorial: Knowledge-Infused Artificial Intelligence For Mental Healthcare, Kaushik Roy Jan 2024

Tutorial: Knowledge-Infused Artificial Intelligence For Mental Healthcare, Kaushik Roy

Publications

Artificial Intelligence (AI) systems for mental healthcare (MHCare) have been ever-growing after realizing the importance of early interventions for patients with chronic mental health (MH) conditions. Social media (SocMedia) emerged as the go-to platform for supporting patients seeking MHCare. The creation of peer-support groups without social stigma has resulted in patients transitioning from clinical settings to SocMedia supported interactions for quick help. Researchers started exploring SocMedia content in search of cues that showcase correlation or causation between different MH conditions to design better interventional strategies. User-level Classification-based AI systems were designed to leverage diverse SocMedia data from various MH conditions, …


K-Perm: Personalized Response Generation Using Dynamic Knowledge Retrieval And Persona-Adaptive Queries, Kanak Raj, Kaushik Roy, Vamshi Bonagiri, Priyanshul Govil, Krishnaprasad Thirunarayan, Raxit Goswami, Manas Gaur Jan 2024

K-Perm: Personalized Response Generation Using Dynamic Knowledge Retrieval And Persona-Adaptive Queries, Kanak Raj, Kaushik Roy, Vamshi Bonagiri, Priyanshul Govil, Krishnaprasad Thirunarayan, Raxit Goswami, Manas Gaur

Publications

Personalizing conversational agents can enhance the quality of conversations and increase user engagement. However, they often lack external knowledge to tend to a user’s persona appropriately. This is particularly crucial for practical applications like mental health support, nutrition planning, culturally sensitive conversations, or reducing toxic behavior in conversational agents. To enhance the relevance and comprehensiveness of personalized responses, we propose using a two-step approach that involves (1) selectively integrating user personas and (2) contextualizing the response with supplementing information from a background knowledge source. We develop K-PERM (Knowledge-guided PErsonalization with Reward Modulation), a dynamic conversational agent that combines these elements. …


Exploring Alternative Approaches To Language Modeling For Learning From Data And Knowledge, Yuxin Zi, Kaushik Roy, Vignesh Narayanan, Amit Sheth Jan 2024

Exploring Alternative Approaches To Language Modeling For Learning From Data And Knowledge, Yuxin Zi, Kaushik Roy, Vignesh Narayanan, Amit Sheth

Publications

Despite their wide applications to language understanding tasks, large language models (LLMs) still face challenges such as hallucinations - the occasional fabrication of information, and alignment issues - the lack of associations with human-curated world models (e.g., intuitive physics or common-sense knowledge). Additionally, the black-box nature of LLMs makes it highly challenging to train them meaningfully in order to achieve a desired behavior. Specifically, the attempt to adjust LLMs’ concept embedding spaces can be highly intractable, which involves analyzing the implicit impact on LLMs’ numerous parameters and the resulting inductive biases. This paper proposes a novel architecture that wraps powerful …


Causal Event Graph-Guided Language-Based Spatiotemporal Question Answering, Kaushik Roy, Alessandro Oltramari, Yuxin Zi, Chathurangi Shyalika, Vignesh Narayanan, Amit Sheth Jan 2024

Causal Event Graph-Guided Language-Based Spatiotemporal Question Answering, Kaushik Roy, Alessandro Oltramari, Yuxin Zi, Chathurangi Shyalika, Vignesh Narayanan, Amit Sheth

Publications

Large Language Models have excelled at encoding and leveraging language patterns in large text-based corpora for various tasks, including spatiotemporal event-based question answering (QA). However, due to encoding a text-based projection of the world, they have also been shown to lack a fullbodied understanding of such events, e.g., a sense of intuitive physics, and cause-and-effect relationships among events. In this work, we propose using causal event graphs (CEGs) to enhance language understanding of spatiotemporal events in language models, using a novel approach that also provides proofs for the model’s capture of the CEGs. A CEG consists of events denoted by …


Ontolog Summit 2024 Talk Report: Healthcare Assistance Challenges-Driven Neurosymbolic Ai, Kaushik Roy Jan 2024

Ontolog Summit 2024 Talk Report: Healthcare Assistance Challenges-Driven Neurosymbolic Ai, Kaushik Roy

Publications

Although Artificial Intelligence technology has proven effective in providing healthcare assistance by analyzing health data, it still falls short in supporting decision-making. This deficiency largely stems from the predominance of opaque neural networks, particularly in mental health care AI applications, which raise concerns about their unpredictable and unverifiable nature. This skepticism hinders the transition from information support to decision support. This presentation will explore neurosymbolic approaches that combine neural networks with symbolic control and verification mechanisms. These approaches aim to unlock AI’s full potential by enhancing information analysis and decision-making support for healthcare assistance1.


An Ontology Design Pattern For Representing Causality, Utkarshani Jaimini, Cory Henson, Amit Sheth Nov 2023

An Ontology Design Pattern For Representing Causality, Utkarshani Jaimini, Cory Henson, Amit Sheth

Publications

The causal pattern is a proposed ontology design pattern for representing the structure of causal relations in a knowledge graph. This pattern is grounded in the concepts defined and used by the CausalAI community i.e., Causal Bayesian Networks and do-calculus. Specifically, the pattern models three primary concepts: (1) causal relations, (2) causal event roles, and (3) causal effect weights. Two use cases involving a sprinkler system and asthma patients are provided along with their relevant competency questions.


Eeg Functional Connectivity In Infants At Elevated Familial Likelihood For Autism Spectrum Disorder, Christian O'Reilly, Scott Huberty, Stefon Van Noordt, James Desjardins, Nicky Wright, Julie Scorah, Sara Jane Webb, Mayada Elsabbagh, Basis Team Oct 2023

Eeg Functional Connectivity In Infants At Elevated Familial Likelihood For Autism Spectrum Disorder, Christian O'Reilly, Scott Huberty, Stefon Van Noordt, James Desjardins, Nicky Wright, Julie Scorah, Sara Jane Webb, Mayada Elsabbagh, Basis Team

Publications

Background

Many studies have reported that autism spectrum disorder (ASD) is associated with atypical structural and functional connectivity. However, we know relatively little about the development of these differences in infancy.

Methods

We used a high-density electroencephalogram (EEG) dataset pooled from two independent infant sibling cohorts, to characterize such neurodevelopmental deviations during the first years of life. EEG was recorded at 6 and 12 months of age in infants at typical (N = 92) or elevated likelihood for ASD (N = 90), determined by the presence of an older sibling with ASD. We computed the functional connectivity between …


Harnessing Surrogate Modeling And Machine Learning For Management Of Water Resources And Environmental Systems, Mahdi Erfani Oct 2023

Harnessing Surrogate Modeling And Machine Learning For Management Of Water Resources And Environmental Systems, Mahdi Erfani

Theses and Dissertations

In a world characterized by increasing and more frequent climate extreme events, population growth, and limited opportunities for infrastructural expansion, the imperative for more efficient and resilient planning, design, and operation of water resources and environmental systems has never been more apparent. Moreover, the emergence of high-dimensional data and the demand for quick and informed decision-making have created a critical challenge for the operation and management of these systems. To address these issues effectively, the ability to rapidly grasp and accelerate the analysis of this data is paramount, and this necessitates the innovative use of machine learning and surrogate modeling …


Evaluation Of The Dynamic Response Of Gravelly Soil Under Different Drainage Conditions, Pressley Margaret Perry Oct 2023

Evaluation Of The Dynamic Response Of Gravelly Soil Under Different Drainage Conditions, Pressley Margaret Perry

Theses and Dissertations

Throughout history in the field of geotechnical earthquake engineering, there have been numerous experimental investigations on the dynamic behavior of soils. Many of these efforts have been focused on sand and silty sand material due to their susceptibility to liquefaction phenomena. However, gravelly soil material (i.e., soil in which gradation contains primarily gravel and sand) has exhibited this phenomenon in response to earthquake loading in many case histories. Therefore, it is important to extend the experimental assessment of gravelly soil material to develop a better understanding of the cyclic response and to support the development of numerical models. This study …


Polybenzimidazole Membranes For Electrochemical Applications With Harsh Operating Conditions, Kris Likit-Anurak Oct 2023

Polybenzimidazole Membranes For Electrochemical Applications With Harsh Operating Conditions, Kris Likit-Anurak

Theses and Dissertations

Polybenzimidazole (PBI) membranes are high temperature proton exchange membranes (PEMs) which have advantages such as being able to operate in high temperatures, strong acid environments, and have no need for external humidity during operation. PBI membranes have been demonstrated to work effectively in multiple electrochemical devices, including fuel cells, hydrogen separation pumps, redox flow batteries, and a hybrid sulfur electrolyzer. In this work, para-PBI and densified para-PBI membrane have been used to improve electrochemical performance in harsh operating conditions that are both high temperature (≥120 ̊C) and high acid concentration (≥ 5M). First, we demonstrated the use of para-PBI membranes …


Probabilistic Cable Aging Diagnosis And Prognosis With Reflectometry And Capacitance Methods, Xuan Wang Oct 2023

Probabilistic Cable Aging Diagnosis And Prognosis With Reflectometry And Capacitance Methods, Xuan Wang

Theses and Dissertations

Safe and reliable operation of power plants and power transmission are critical to economy and society. Cables in power generation and transmission are subject to various thermal, chemical, and mechanical stresses, which generally lead to aging and degradation of cable insulation. It is reported that some cables with a projected lifetime of 40 years need to be replaced in 10-15 years. Poorly maintained aged cables can adversely affect power delivery and lead to catastrophic events, such as blackout, fires, and loss of lives. The current research on cable is mainly focused on the detection and localization of hard faults, which …


Field And Laboratory Characterization Of Subgrade Resilient Modulus For The Aashtoware Pavement Me, Kazi Moninul Islam Oct 2023

Field And Laboratory Characterization Of Subgrade Resilient Modulus For The Aashtoware Pavement Me, Kazi Moninul Islam

Theses and Dissertations

The new Mechanistic-Empirical Pavement Design Guide (MEPDG) uses the subgrade resilient modulus (MR) as the key input parameter to represent the subgrade soil behavior for pavement design. This research focused on field and laboratory characterization of subgrade resilient modulus assessing the effects of predicted distresses and IRI on the flexible pavement. The results of this study are presented in the form of three chapters and peer-reviewed journal manuscripts. Firstly (Chapter 3), MR was obtained indirectly from Falling Weight Deflectometer (FWD) data using a back-calculation tool (i.e., SCDOT, BAKFAA, and AASHTOWare 2017) or from empirical correlations with soil index properties. MR …


Heterogeneous Catalyst Design For Biomass Conversion, Dia Sahsah Oct 2023

Heterogeneous Catalyst Design For Biomass Conversion, Dia Sahsah

Theses and Dissertations

Catalytic upgrading of bio-based feedstocks to commodity chemicals and fuels is pivotal to a more sustainable, renewable, and environmentally benign chemical economy. However, due to the high oxygen content, high water solubility, excessive reactivity, and thermal instability, typical and well-developed catalytic material and reactor processes reliably utilized in conventional petrochemical industry are, in general, not suitable for the processing of biomass feedstocks. Therefore, the development of novel heterogeneous catalysts is necessary in order to design new high-performance catalytic reactor systems. However, rational catalyst design is a multifaceted problem, and a myriad of factors influencing the catalytic performance at the reactor …


Floodplain And In-Channel Sedimentation In The Bedrock Congaree River, Sc, Mahsa Ahmadpoor Oct 2023

Floodplain And In-Channel Sedimentation In The Bedrock Congaree River, Sc, Mahsa Ahmadpoor

Theses and Dissertations

The Congaree River planform is characterized by an abrupt increase in channel sinuosity in the downstream direction. Such a change is not typical of alluvial meandering rivers but has been observed in mixed bedrock-alluvial rivers. This motivated the first study of this dissertation, specifically designed to determine if the Congaree River is indeed a mixed bedrock-alluvial river in its low sinuosity (upstream) reach. To test this hypothesis, sonar-based measurements of channel bed and sublayer elevation were performed from Columbia to the Congaree River-Wateree River confluence. The sublayer is here defined as the first surface visible in the sonar measurements underneath …


Investigation Of Discrepancies In South Carolina Traffic Collision Forms, Jackson Wegmet Oct 2023

Investigation Of Discrepancies In South Carolina Traffic Collision Forms, Jackson Wegmet

Theses and Dissertations

The aim of this thesis is to improve the accuracy of information recorded in the South Carolina traffic collision forms. To accomplish this, it examines 200 forms containing information about fatal crashes in work zones between 2014 and 2020 to determine how many discrepancies exist between the written narrative and other fields. In addition to obtaining these statistics, this thesis seeks to identify factors that influence discrepancies. To test the hypothesis that crash complexity and weather influence the investigating officer’s level of processing (a theory developed by Craik and Lockhart in 1972), and consequentially his/her ability to complete the traffic …


Water Quality Monitoring And Mapping Using Rapidly Deployable Sensor Nodes, Mohamed Abdelwahab Oct 2023

Water Quality Monitoring And Mapping Using Rapidly Deployable Sensor Nodes, Mohamed Abdelwahab

Theses and Dissertations

Efficient and continuous monitoring of water quality parameters plays a pivotal role in responding to pollution incidents and ensuring the safety of both human consumption and ecological resources. This research introduces an affordable and dependable in-situ water quality sensor package designed for seamless continuous monitoring, providing essential data to facilitate informed decision-making in water resource management. The sensor package enables comprehensive on-site assessment of key water characteristics, including pH, temperature, turbidity (measured in NTU), and total dissolved solids (TDS, measured in ppm). Spatial interpolation techniques, specifically Kriging, are employed to extrapolate variable values at unobserved locations based on nearby measurements. …


Engineering Hybrid Colloidal Systems Formed By Charge-Driven Assembly Between Spherical Soft Nanoparticles And Discotic Nanoplatelets, Gelareh Rezvan Oct 2023

Engineering Hybrid Colloidal Systems Formed By Charge-Driven Assembly Between Spherical Soft Nanoparticles And Discotic Nanoplatelets, Gelareh Rezvan

Theses and Dissertations

Soft matter, a fascinating class of materials, holds a paramount significance in the realm of material design and engineering. Within this broad category, colloidal gels with their unique characteristics have drawn tremendous attention in a variety of applications, spanning from biomedical engineering to oil and gas recovery. Meeting the specific requirements and criteria of these diverse fields necessitates the development of colloidal gels with highly tunable properties to optimize their performance for a wide range of applications. Hence, both scientific and industrial advancement call for more control over the gel properties by exploring novel practical parameters. This dissertation describes an …


Synthesis And Characterization Of Electrode Materials Of Solid Oxide Cells For Energy Conversion And Storage, Haixia Li Oct 2023

Synthesis And Characterization Of Electrode Materials Of Solid Oxide Cells For Energy Conversion And Storage, Haixia Li

Theses and Dissertations

Solid oxide cells (SOCs) can directly convert chemical energy to electricity in the fuel cell mode and store electricity to chemicals in the electrolysis mode. However, there are still critical barriers, such as energy efficiency and durability, for developing and commercializing SOCs. This dissertation aims to design electrode materials and optimize the cell fabrication process to address the critical barriers for SOCs in energy conversion and energy storage applications. Therefore, one primary focus of the dissertation is to develop robust fuel electrode material for solid oxide fuel cells (SOFCs) with improved sulfur tolerance. In addition, the design of novel fuel …


Wide View And Line Filter For Enhanced Image Gradient Computation And Edge Determination, Luke Bagan Oct 2023

Wide View And Line Filter For Enhanced Image Gradient Computation And Edge Determination, Luke Bagan

Theses and Dissertations

Edge determination is a challenging yet crucial step in the object detection process for images. It is the first in a multi-step process, serving as the foundation for all subsequent operations. Its accuracy directly affects the success of any future processing techniques and final detection. The challenge of edge detection is derived from a variety of factors, including noise, image sharpness, orientation, empirical parameters, and computational complexity. Many traditional kernel-based operators excel at tackling one of these problems, but trade off their ability to handle others. For example, the popular Sobel operator uses a horizontal and vertical constant high-pass kernel. …


Circularly-Shifted Chirps For Triple Functionality: Communications, Radar, And Computation, Safi Shams Muhtasimul Hoque Oct 2023

Circularly-Shifted Chirps For Triple Functionality: Communications, Radar, And Computation, Safi Shams Muhtasimul Hoque

Theses and Dissertations

This dissertation presents circularly-shifted chirps (CSCs), synthesized within orthogonal frequency domain multiplexing (OFDM) framework, as a novel solution for integrating radar, communication, and computation functionalities to a wireless network. Firstly, {index modulation (IM)} with circularly-shifted chirps (CSCs) (CSC-IM) for dual-function radar and communication (DFRC) system is discussed. The proposed scheme encodes the information bits with the CSC indices and the phase-shift keying (PSK) symbols. It allows the receiver to exploit the frequency selectivity naturally in fading channels by combining IM and wideband CSCs. It also leverages the fact that a CSC is a constant-envelope signal to achieve a controllable peak-to-mean …


Load Determination, Strengthening, And Behavior Study Of Prestressed Concrete Channel Bridge Girders In South Carolina, Elhussien Khaled Elbatanouny Oct 2023

Load Determination, Strengthening, And Behavior Study Of Prestressed Concrete Channel Bridge Girders In South Carolina, Elhussien Khaled Elbatanouny

Theses and Dissertations

The South Carolina Department of Transportation (SCDOT) is currently engaged in a multi-year effort to assess the structural integrity of its inventory of over 9,000 bridges. This assessment process is expected to result in an increase in the number of bridges that require load postings, repairs, or replacements across South Carolina. This could potentially lead to adverse economic repercussions due to restricted truck routes, bridge closures, repair work, and the need for bridge replacements. To alleviate the escalating costs associated with these challenges, it is imperative to explore methods aimed at reducing the need for load postings and bridge closures …


Acoustic-Emission Monitoring Of Lap Joint Fatigue Cracks, Siddharth Kannan Oct 2023

Acoustic-Emission Monitoring Of Lap Joint Fatigue Cracks, Siddharth Kannan

Theses and Dissertations

Structural integrity is a pivotal consideration in the field of engineering applications, and understanding the behavior of materials and joints under various loading conditions is critical. This thesis presents a novel approach to detect and analyze fatigue induced cracks in various test specimens using Piezoelectric Wafer Active Sensors. This approach is widely used in Structural Health Monitoring applications involving acoustic emissions that can be captured using PWAS which in turn gives the surface response to applied stresses. The ultimate goal of the research is to identify the length of a fatigue crack originating from lap joints and to develop a …


Design Of A Test Frame And Its Corresponding Test Methods For A Deployable Composite Boom, William Luther Montgomery Oct 2023

Design Of A Test Frame And Its Corresponding Test Methods For A Deployable Composite Boom, William Luther Montgomery

Theses and Dissertations

Deployable composite booms (DCB) are an advanced class of support beams growing in applications including solar collectors and solar sails. DCBs can be coiled or folded into a compact footprint and the ability to be deployed, and in some design, concepts redeployed, making them optimal components for aerospace where weight and volume are finite resources. DCBs are a cutting-edge technology that has yet to be perfected with a need for longer booms with increased stiffnesses to accommodate the latest proposed designs. Atomic-6 has proposed a 16-foot boom manufactured using an autoclave process which aims to reach the goal of producing …


Electric Freight Transportation System Planning And Truck Operation Optimizations, Xuanke Wu Oct 2023

Electric Freight Transportation System Planning And Truck Operation Optimizations, Xuanke Wu

Theses and Dissertations

The substantial demand for fossil fuel consumption is a significant contributor to greenhouse gas emissions, drawing considerable public attention to health and environmental problems. As a result, vehicle electrification is currently recognized as the most effective approach to reduce CO2 emissions from transportation. However, compared to traditional fossil fuel-powered vehicles, electric vehicles have notable disadvantages, including higher upfront purchasing price, longer recharging time, and most significantly, lower driving ranges. All these challenges can potentially result in increased overall operational costs for logistics companies. This thesis proposes a comprehensive optimization modeling framework for electric freight transportation system planning and operations with …


Simulation-Based Optimization Of A Dc Microgrid: With Machine-Learning-Based Models And Hybrid Meta-Heuristic Algorithms, Tyler Van Deese Oct 2023

Simulation-Based Optimization Of A Dc Microgrid: With Machine-Learning-Based Models And Hybrid Meta-Heuristic Algorithms, Tyler Van Deese

Theses and Dissertations

The field of economic dispatch (ED) focuses on optimizing power flow in a power system to minimize costs. It has the potential to significantly enhance system effectiveness, and efficiency, and reduce operating costs. Various techniques have been employed to tackle this problem, each with its own strengths and weaknesses. One promising approach is simulation-based optimization (SBO), which allows for accurate modeling of system interactions and improved representation of expected results. However, SBO requires running numerous simulations to identify an optimal solution, and there is a possibility of not achieving the global optimum. This work aims to address these challenges using …


Catalytic Hydrogenation Of Dimethyl Oxalate To Ethylene Glycol Using Silver Based Catalysts On Sba-15, Nicolas Edouard Gleason-Boure Oct 2023

Catalytic Hydrogenation Of Dimethyl Oxalate To Ethylene Glycol Using Silver Based Catalysts On Sba-15, Nicolas Edouard Gleason-Boure

Theses and Dissertations

Ethylene glycol (EG) is an important industrial chemical in the manufacturing of certain plastics. There is growing industrial interest in the production of dimethyl oxalate (DMO) from syngas, which can be hydrogenated to produce EG. Many studies have focused on the catalytic reduction of DMO using copper-based catalysts on silica supports, but fewer studies have been done on the effects of silver for this reaction. This work presents an in-depth study of silver catalysts prepared via various methods including incipient wetness impregnation, charge enhanced dry impregnation, and the use of various organic solvents. Reaction studies show that using pure methanol …


A Globalized Optimization Schema For Automated Fiber Placement Processing Parameters, Matthew John Godbold Oct 2023

A Globalized Optimization Schema For Automated Fiber Placement Processing Parameters, Matthew John Godbold

Theses and Dissertations

Automated Fiber Placement is an advanced manufacturing technique for industrial-scale composite structures. Advanced robotics coupled with composite manufacturing results in faster and more consistent results than previously obtained through hand layup. The complexity and interconnectedness of the automated fiber placement process provides a difficult challenge for traditional modeling techniques. Modeling within automated fiber placement currently utilizes physics-based modeling to inform the translation of a design to a manufacturing plan. The intricacy of the automated fiber placement process dictates that attempts at modeling or optimizing these processes are often limited in their scope. Physics-based modeling for manufacturing typically involves numerous interacting …