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High Viscosity Friction Reducer Evaluation At High Temperature And High Tds Environments, Ghith Ali Ahmed Biheri

Doctoral Dissertations

"In unconventional reservoirs, proppant transport during hydraulic fracturing treatments could be successful when the proppant is placed further within the reservoir's fracture networks. This could increase the reservoir formation conductivities and improve the productivity of the wells. This job of improving the reservoir conductivity by distributing and transporting proppant can be conducted by reliable fracture fluids with excellent fluid rheology (e.g., viscosity and elasticity). However, several challenges, including the high temperatures and the presence of high TDS in produced water, may limit the capability of fracture fluids to transport proppant. Additionally, the use of fracture fluid has raised fears regarding …

A Structure From Motion Photogrammetric Method For Continuously Measuring And Tracking The Deformations Of Soils During Triaxial Testing, Xiaolong Xia

Doctoral Dissertations

"Measuring soil deformation characteristics during triaxial testing is an important part of characterizing the stress-strain behavior of both saturated and unsaturated soils. The total and local deformations and volume changes of a soil specimen are indispensable parameters that need to be measured and are of great significance for understanding volume change and shear strength characteristics of the soil. Over the past several decades, numerous efforts have been made to measure the soil deformations during triaxial testing. However, it remains a great challenge for researchers to measure the volume-changes of unsaturated soils due to the existence of the air phase.

This …

Novel Supercritical Biodiesel Plant Design & Process Scale-Up, Ghana Shyam Paudel

Doctoral Dissertations

"Current energy prices, national energy security, and global climate change fuel our momentum to find efficient advanced fuels choices. In this study, biodiesel processing, and a novel design for next generation biodiesel plants are explored. During a National Science Foundation (NSF) I-Corps project we identified three creative and profitable improvements to the process: 1. Incorporating Energy intensive separations and reactions 2. Utilizing Low commodity glycerol and 3. Applying process intensification principles.

Current biodiesel processes are catalyzed processes using continuous stir reactors with distillation systems to separate material constituents. We tested a lab-scale nocatalyst supercritical biodiesel process using waste cooking oil …

Sustainable Cementitious Materials For Building And Sorption Applications, Sukanta Kumar Mondal

Doctoral Dissertations

"Ordinary Portland Cement (OPC) is the most widely used cement material, but it contributes over 8% of the global CO₂ emission and the process is energy intensive. Moreover, OPC faces durability challenges, particularly in aggressive environments. Hence, there is rapidly increasing interest in sustainable alternative cements with lower carbon footprint, lower energy consumption, and those that offer superior properties that are beneficial for specific applications. Two sustainable cementitious materials that are frequently researched as an alternative to OPC are calcium sulfoaluminate (CSA) cement and alkali-activated materials (AAMs). CSA cement lowers CO₂ emission by over 40% compared to OPC, …

Re-Evaluating Missouri’S Strategic Element Potential: A Geochemical Study Of The Mesoproterozoic Fe-Cu-Co-Ree Deposits In Southeast Missouri, Usa, Brandon James Sullivan

Doctoral Dissertations

"Iron-oxide-copper-gold (IOCG) deposits are poorly understood mineral systems. For example, we do not know why Cu- and Co-rich IOCG deposits typically occur proximal to Fe ore deposits that are notably Cu and Co-poor, such as Iron Oxide Apatite (IOA) deposits. To better understand the formation of IOA and IOCG deposits in Missouri, USA, this PhD thesis examines the genesis of the Kratz Spring IOA and the Boss Central Dome IOCG deposits. This study presents the first constraints on formation conditions and fluid sources in the studied deposits using integrated petrographic, mineral composition, and Fe isotope analyses of oxide minerals. Observations …

Advancing A Systems Perspective On Innovative Behavior, Stephen Demski

Doctoral Dissertations

"Engineering organizations pursue innovation in strategy, structure, processes, and the services and products offered to remain relevant and competitive. Identifying factors supporting or constraining innovative work behavior and recognizing the complexity of their interactions are vital to sustaining an innovative workforce, yet how factors interact has not been comprehensively studied.

Recognizing innovative work behavior as the output of a complex system of factors guided this study’s literature search that identified over one hundred individual, team, and organizational factors influencing innovative behavior, interviews of engineers to learn what factors are essential in their work environment, and Delphi survey to rank factors, …

Advanced Manufacturing Of Nanomaterials For Energy Storage And Biomedical Applications, Hiep Pham

Doctoral Dissertations

"Nanomaterials have emerged as an important component to the advancement of many fields, ranging from advanced energy materials in the energy field to highly sophisticated treatment vehicles in the biomedical field. Understanding the physical behavior of nanomaterials is critical to design materials with excellent properties and performance for the many disciplines in which they are utilized and is necessary to master the various manufacturing processes that influence nanomaterial properties and behavior. This research focused on a fundamental study into the behaviors of newly developed nanomaterials under both conventional and new manufacturing processes for high performance lithium-ion batteries and for advanced …

Investigation Of Asphaltene Instability Under Gas Injection In Unconventional Reservoirs And Its Impact On Oil Recovery Performance, Mukhtar Elturki

Doctoral Dissertations

"Unconventional reservoirs, such as shale gas and tight oil formations, have become an important source of energy in recent years. However, these reservoirs often contain high levels of asphaltenes, which can lead to deposition and blockages in production wells and reduce the flow of hydrocarbons during gas enhanced oil recovery (GEOR) techniques. This study aims to experimentally evaluate the impact of miscible and immiscible carbon dioxide (CO₂) and nitrogen (N₂) on asphaltene deposition and its impact on oil recovery performance in unconventional shale reservoirs.

This research began with a comprehensive literature review and data analysis of GEOR methods in unconventional …

Monitoring And Control Of Coal Dust Exposure Using Low-Cost Pm Sensors And Computational Fluid Dynamics, Nana Kobina Amoako Amoah

Doctoral Dissertations

"Overexposure to respirable coal mine dust has been linked to causing serious health problems including coal workers pneumoconiosis (CWP) and chronic massive fibrosis. The prevalence of these health problems has been on the increase since the 2000s due to increased exposure levels with roof bolter operators having the highest exposure levels. The currently used PDM3700 is too expensive, heavy and bulky which limits their use only for regulatory monitoring failing to measure miners’ personal exposure levels. Also, since roof bolter operators are more prone to elevated coal dust levels, the canopy air curtain (CAC) was developed to protect then high …

Modeling And Analysis Methods For Esd And Emi Problems, Xin Yan

Doctoral Dissertations

"Electrostatic discharge (ESD) failures and Electromagnetic interference (EMI) problems are becoming more critical in electronic devices and large systems. In this work, four studies are presented to model and analyze ESD and EMI problems.

First, a simplified physical-based model for deep-snapback transient voltage suppressors (TVS) is developed. While based on physics, the number of parameters and components is minimized. Results show that the proposed model captures the most important behaviors of the TVS response using a limited number of parameters, allowing the model to be tuned relatively easily using data obtained only from package-level transient and quasi-static measurements. Second, a …

Chirality Determination Using Three-Wave Mixing Microwave Spectroscopy, Nicole Taylor Moon

Doctoral Dissertations

"Rotational spectroscopy has established itself as a reliable gas-phase spectroscopic technique for the structural determination of molecules. This reliability has stemmed from both advancements in microwave technology and a willingness from the community to push the boundaries of the field. In this dissertation, the boundaries are tested in both how well the technique can determine the structure of molecules exhibiting large amplitude motion and through chirality determination. The first half of this dissertation explores the use of deep averaging to determine the structure of silicon containing molecules in collaboration with Dr. Guirgis from the College of Charleston. For each of …

Control And Optimization Of Energy Storage System In Power Distribution System, Waqas Ur Rehman

Doctoral Dissertations

"The widespread adoption of electric vehicles (EVs) and transportation electrification is encumbered by two chief barriers: i) the limited driving range of EVs in the market today and ii) inadequate fast-charging infrastructure for long-distance trips. Extreme fast charging (XFC) technology can recharge EVs in less than 10 minutes for 200 miles range. Firstly, a novel robust optimization-based mixed integer linear programming model is proposed to size a battery energy storage system (BESS) and PV system in an XFCS. In this part, it is assumed that the sizing and location of the XFCS are known. Secondly, the aforesaid assumption is relaxed, …

Low-Shrinkage Fiber-Reinforced Concrete For Infrastructure Construction And Rehabilitation, Jingjie Wei

Doctoral Dissertations

"The aim of this study is to develop two classes of low-shrinkage high-performance concrete (HPC): fiber-reinforced super workable concrete (FR-SWC) for infrastructure construction and fiber-reinforced self-consolidating concrete (FR-SCC) for repair applications. HPC with excess content of shrinkage mitigation materials (SMMs), including shrinkage-reducing admixture (SRA), superabsorbent polymer (SAP), and expansive agent (EA) has a detrimental effect on mechanical performance. These classes of HPC were optimized to reduce shrinkage, enhance mechanical properties, and improve durability. The effect of fiber type (macro synthetic fiber, MSF; 5D steel fiber, 5D; 80% 3D + 20% short steel fibers; STST), SMMs, and plastic viscosity on bond …

The Science Of Gravitational-Wave Sources And Beyond Compact Binary Coalescences, Yanyan Zheng

Doctoral Dissertations

"This work focuses on the field of gravitational-wave astronomy by extending the scope of detectable sources beyond compact binary coalescences, All the gravitational-wave detections so far come from compact binary coalescences. Focusing on core-collapse supernovae as promising sources for short gravitational-wave transients, this work reports optically targeted searches for gravitational-wave emitted by core-collapse supernovae during the third observing run of the LIGO and Virgo detectors. It also predicts the search sensitivity for the ongoing fourth and forthcoming fifth observing runs. Moreover, the work introduces a novel computational framework for testing the spatial distribution of binary black hole sources, allowing for …

Additive Manufacturing Of Steel And Aluminum Structures: Modeling And Experiments, Manoj Kumar Reddy Rangapuram

Doctoral Dissertations

"Additive manufacturing (AM) is defined as the process of joining materials to make objects from three-dimensional model data. Complex geometries can be easily manufactured compared to conventional subtractive methods with more freedom and flexibility in the design process. As the demand for AM process increased, it has become critical to understand the process and various parameters that constitute in affecting the quality of the manufactured part. Conducting experiments can be time intensive and costly to optimize a process. Modeling can be used as an aid to optimize, examine, and predict the process outcome.

The objective of this study is (i) …

Equivalent Source Investigation For Pcb Vibration Excited By A Multilayer Ceramic Capacitor, Yifan Ding, Ming Feng Xue, Jianmin Zhang, Xin Hua, Benjamin Leung, Eric A. Macintosh, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Multilayer ceramic capacitors (MLCCs) are commonly used on printed circuit board (PCB) power distribution networks (PDN) for decoupling purposes. However, an MLCC can act as a source to excite PCB vibrations due to noise ripples on the power rail. In this letter, four types of equivalent source configurations are studied and compared to represent the excitation of an MLCC on a PCB driven by power rail noise. The corresponding source values are extracted at test-vehicle PCB resonance frequencies. The investigation of the four equivalent source types involves a comparison between simulated and measured PCB vibration velocity responses triggered by MLCC …

A Robust Demand Regulation Strategy For Ders In A Single-Controllable Active Distribution Network, Shah Fahad, Arman Goudarzi, Rui Bo, Muhammad Waseem, Rashid Al-Ammari, Atif Iqbal

Electrical and Computer Engineering Faculty Research & Creative Works

Over the past decade, pq regulation schemes for a single-controllable active distribution network (adn) using coordination among a network of virtual synchronous generators (vsgs) have been proposed. However, considering the variable nature of intermittent renewable energy sources (iress), coupling a cluster of iress with the point of common coupling (pcc) of adn could inflict transient issues for the power management of the whole adn. To counter these challenges, the proposed study has three main objectives: 1) to propose a modified mathematical model that represents the apparent resistance-reactance at the pcc of adn in relation to the pq coordination among the …

High-Speed Channel Simulator Using Neural Language Models, Hyunwook Park, Yifan Ding, Ling Zhang, Natalia Bondarenko, Hanqin Ye, Brice Achkir, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, high-speed channel simulators using neural language models are proposed. Given the input sequence of geometry design parameters of differential channels, the proposed channel simulator predicts SI characteristic sequences such as insertion loss (IL) and far-end crosstalk (FEXT). Sequence-to-sequence (seq2seq) networks using a recurrent neural network (RNN) and a long short-term memory (LSTM) are utilized for the estimator. Moreover, a transformer network which is a recent neural engine of large language models (LLMs) is introduced for the first time. Compared to seq2seq networks, the transformer network-based simulator can achieve shorter computing time due to its parallel computation called …

Modeling Of Power Distrubition Network (Pdn) Noise Coupling Induced Clock Phase Noise, Zhekun Peng, Junyong Park, Chaofeng Li, Joey Stecher, Srinivas Venkataraman, Xu Wang, Granthana Rangaswamy, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

Phase noise analysis is important to clock design. Noise sources of spurs shown on the phase noise result are challenging to find out due to the unknown source locations and coupling mechanisms. Noise from power distribution network (PDN) is one of the most troublesome sources. A behavioral modeling methodology is proposed to simulate the clock phase noise induced by PDN noise coupling for two different mechanisms: PDN-to-clock additive coupling and PDN-to-PDN up-conversion modulation. The thermal noise and 1/f flicker noise are simplified to provide a straightforward view of spur level. The model can be applied to both single-ended clock and …

Suppression Of Power Distribution Network Pcb-Package Resonance For Low Target Impedance, Francesco De Paulis, Faye Squires, Yifan Ding, Matteo Cocchini, Matthew Doyle, Samuel Connor, Albert E. Ruehli, Chulsoon Hwang, Lijun Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

The suppression of the large resonance peak that may appear due to the equivalent parallel circuit between the package capacitance and PCB inductance is discussed. Such resonance may be amplified if the decoupling capacitors are not appropriately selected. The relevant parameters involved in the PDN design, and a feasible solution strategy are presented based on the identification of a simplified equivalent circuit that is able to replicate the resonant behavior. The optimization of the relevant parameters of such circuit are able to suggest the best strategy for identifying the decoupling capacitors with appropriate values of parasitic inductance and resistance.

Online Continual Safe Reinforcement Learning-Based Optimal Control Of Mobile Robot Formations, Irfan Ganie, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, a leader-follower tracking and formation control strategy for mobile robots (MRs) with uncertain dynamics is proposed. This strategy utilizes a continual lifelong safe reinforcement learning (CLSRL) framework based on multilayer neural networks (MNNs). The proposed design employs actor-critic MNNs, incorporating a barrier function. This function is derived from the Bellman optimality principle. It addresses the state constraints throughout the control design process. A novel online continual lifelong learning (CLL) method is introduced for MR formation. This method leverages the Bellman residual error for weight significance in MNNs. It addresses catastrophic forgetting and interlayer dependence through layer-specific regularizers. …

Visualization Of Noise Coupling Paths Based On The Reciprocity Theorem, Seungtaek Jeong, Jong Hwa Kwon, Deepak Pai, Jagan Rajagopalan, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

In this article, visualization of noise coupling paths is proposed and verified. The coupling coefficient (CC) is derived based on the Reciprocity theorem and time-average coupled power, which represents the contribution of each spatial point to the coupled power. The physical meaning of CC is demonstrated by relating the integrations of CC in a volume space occupied by absorbers to the coupled power being suppressed by the absorbers. The proposed method is applied to a practical device and the identified dominant coupling paths are experimentally verified.

Tilted Fiber Bragg Grating Sensors Based On Time-Domain Measurements With Microwave Photonics, Shiyu Li, Ruimin Jie, Osamah Alsalman, Jie Huang, Chen Zhu

Electrical and Computer Engineering Faculty Research & Creative Works

Tilted fiber Bragg gratings (TFBGs) have garnered substantial research attention and have found widespread applications for sensing a diverse array of physical, chemical, and biological parameters based on optical spectrum measurements. The interrogation of a TFBG sensor typically requires a high-resolution bulky optical spectrum analyzer (OSA) due to the extremely narrow dips caused by the resonance of cladding modes. However, high-resolution OSAs can be costly and have limitations on measuring speed, limiting their practicality. In this paper, a new approach to interrogating TFBG sensors is proposed and experimentally demonstrated based on a microwave photonics technique. Instead of measuring the optical …

Special Session: Writing For The Ieee Teaching Excellence Hub, Steve Eugene Watkins

Electrical and Computer Engineering Faculty Research & Creative Works

Technical educators can benefit by sharing practices, techniques, experiences, and approaches that have been successful in their classrooms. The IEEE Teaching Excellence Hub (TEH) provides curated educational materials and resources for those teaching engineering, computing, and technology at the university level. This virtual venue for professional development is intended to complement resources found through educational journals and conferences. The online site contains practice-oriented articles, event links, and other collections that are contributed by the engineering education community. This special session will provide an overview of the TEH platform and will prepare attendees for contributing as reviewers and authors. The target …

2023 Scholarly Productivity Report, Missouri University Of Science And Technology

Civil, Architectural and Environmental Engineering Scholarly Productivity Reports

No abstract provided.

Ai-Enabled Assessment Of Roadway Integrity: Forecasting Bitumen Deformation And Road Stability Throughout The Lifecycle Under Traffic Impact, Sabahudin Vrtagic, Milan Dordevic, Fatih Dogan, Muhammed Codur, Mario Hoxha, Edis Softic

Materials Science and Engineering Faculty Research & Creative Works

Asphalt-paved Road junctions frequently encounter deformation and degradation challenges due to heavy vehicular traffic and varying climatic conditions, such as temperature fluctuations and precipitation. This study employs a multifaceted approach, incorporating a Multilayer Perceptron (MLP) model, ancillary machine learning techniques, and optimization methodologies, to address these challenges effectively. The primary objectives are the prediction and analysis of pavement deformation, the optimization of maintenance strategies, and the evaluation of road effectiveness. Our findings underscore the substantial contribution of heavy vehicles to road erosion and the profound impact of vehicular retention and braking at intersections. A Multilayer Perceptron (MLP) model is utilized …

Enhancing Diversity And Inclusion In Computer Science Undergraduate Programs: The Role Of Admissions, Ouldooz Baghban Karimi, Giulia Toti, Mirela Gutica, Rebecca Robinson, Lisa Zhang, James Paterson, Peggy Lindner, Michael O'Dea

Engineering Management and Systems Engineering Faculty Research & Creative Works

Despite continued efforts to further the participation of women in Computer Science (CS), progress has been limited during the past decades. Recent efforts have been focused on recruitment and retention, with a notable gap in exploring the impact of admissions processes on diversity and inclusion. Through an extensive literature review, contextual analysis of public admissions data from 40 universities across four regions around the world, and qualitative and quantitative analysis on surveys and interviews, we explored the role of admissions in enhancing diversity and inclusion in CS undergraduate programs. Our findings highlight the role of financials, the possible positive effects …

Synaptic Plasticity Emulation By Natural Biomaterial Honey-Cnt-Based Memristors, Zoe Templin, Md Mehedi Hasan Tanim, Feng Zhao

Electrical and Computer Engineering Faculty Research & Creative Works

Artificial synaptic devices made from natural biomaterials capable of emulating functions of biological synapses, such as synaptic plasticity and memory functions, are desirable for the construction of brain-inspired neuromorphic computing systems. The metal/dielectric/metal device structure is analogous to the pre-synapse/synaptic cleft/post-synapse structure of the biological neuron, while using natural biomaterials promotes ecologically friendly, sustainable, renewable, and low-cost electronic devices. In this work, artificial synaptic devices made from honey mixed with carbon nanotubes, honey-carbon nanotube (CNT) memristors, were investigated. The devices emulated spike-timing-dependent plasticity, with synaptic weight as high as 500%, and demonstrated a paired-pulse facilitation gain of 800%, which is …

Occupational And Environmental Factors Influencing Morale Of United States Federal Wildland Firefighters, Rachel M. Granberg, Ting Shen, Seth W. Pearson, Robin M. Verble

Psychological Science Faculty Research & Creative Works

Background. Wildland firefighters have physically and psychologically demanding jobs that can result in social, economic and health-related stress. Previous studies have examined the physiological and physical effects of a career in wildland fire, but fewer studies have addressed psychological effects, and to date, none have directly analyzed the hiring and work experiences of wildland firefighters. Aims. We surveyed work experiences, health and well-being, and morale of wildland firefighters, explored factors that can improve recruitment and retention, and summarized broad patterns. Methods. We conducted a voluntary anonymous survey of 708 federal wildland firefighters via an online platform over 2 months in …

Design And Performance Of Fiber-Reinforced Shrinkage Compensating Eco-Friendly Concrete, Kamran Aghaee, Kamal Khayat

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Eco-Crete is an ecological and economical concrete that benefits from high packing density of solid materials and reduced paste. Eco-Crete can enhance the service life of structures by reducing the risk of shrinkage cracking. In this study, shrinkage mitigating materials included an expansive agent (EA), a shrinkage reducing admixture (SRA), and a lightweight sand (LWS), as well as steel and synthetic fibers were used to minimize the risk of cracking. A total of 35 fiber-reinforced Eco-Crete mixtures were prepared with 350 kg/m3 of cementitious materials and 55 % substitution of fly ash and slag. Key fresh and mechanical properties in …