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Roughness Losses Computation Through The Partial Elements Equivalent Circuit Method, Fabrizio Loreto, Daniele Romano, Giulio Antonini, Albert E. Ruehli, Mauro Lai Jan 2023

Roughness Losses Computation Through The Partial Elements Equivalent Circuit Method, Fabrizio Loreto, Daniele Romano, Giulio Antonini, Albert E. Ruehli, Mauro Lai

Electrical and Computer Engineering Faculty Research & Creative Works

Conductor Loss Caused by Conductor Surface Roughness is a Critical Aspect in the Design of High-Speed Electronic Systems Since It Significantly Affects their Performances. Well-Established Roughness Models Have Been Proposed over the Years but They Have Been Applied Only to the Transmission Line Models of Interconnects. Typically, the Roughness Models Are Used to Modify the Per-Unit-Length Impedance of the Transmission Line Which is Extracted by 2D Model Methods. The Aim of This Work is to overcome This Limitation Thus Making It Possible to Model Roughness Conductors in the Framework of 3D Full-Wave Methods. More Precisely, it is Presented How to …

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Near Field Scanning-Based Emi Radiation Root Cause Analysis In An Ssd, Xiangrui Su, Wenchang Huang, Junghee Cho, Joonki Paek, Chulsoon Hwang Jan 2023

Near Field Scanning-Based Emi Radiation Root Cause Analysis In An Ssd, Xiangrui Su, Wenchang Huang, Junghee Cho, Joonki Paek, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

In Modern Portable Electronic Devices, Solid-State Drives (SSDs) Are Commonly Used and Have Been Identified as One of the Dominant Electromagnetic Interference (EMI) Noise Sources that Can Cause RF Desensitization Issues. in This Paper, the EM Emission Source from an SSD Module is Identified and Analyzed using Near Field Scanning and Dipole Moment Source Reconstruction. the Identified Noise Current Path Including the Power Management Integrated Circuit and the Decoupling Capacitor is Validated with the Assistance of Full-Wave Simulation. the Measured Noise Voltage is Used as an Excitation in the Simulation and the Simulated Near Fields Showed a Good Correlation with …

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A Real-Time Microwave Camera Prototype With Zero-Bias Diode Detectors For Emi Source Imaging, Xin Yan, Liang Liu, Victor Khilkevich Jan 2023

A Real-Time Microwave Camera Prototype With Zero-Bias Diode Detectors For Emi Source Imaging, Xin Yan, Liang Liu, Victor Khilkevich

Electrical and Computer Engineering Faculty Research & Creative Works

Emission Source Microscopy (ESM) Could Be Utilized to Localize the Electromagnetic Interference (EMI) Sources that Contribute to the Far-Field Radiation. in Those Cases, the Electrical Field over a Two-Dimensional Plane is Collected by Mechanical Scanning, Resulting in a Long Measurement Time and the Presence of Mechanical Errors. in This Work, a Microwave Camera based on a Two-Dimensional Array of Elliptical Slot Antennas and Diode Detectors is Presented. Multiplexers Are Utilized to Access the Output of Each Detector and the Scanning of the Whole Array Could Be Done Multiple Times Per Second.

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Lifelong Learning Control Of Nonlinear Systems With Constraints Using Multilayer Neural Networks With Application To Mobile Robot Tracking, Irfan Ganie, S. (Sarangapani) Jagannathan Jan 2023

Lifelong Learning Control Of Nonlinear Systems With Constraints Using Multilayer Neural Networks With Application To Mobile Robot Tracking, Irfan Ganie, S. (Sarangapani) Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Presents a Novel Lifelong Multilayer Neural Network (MNN) Tracking Approach for an Uncertain Nonlinear Continuous-Time Strict Feedback System that is Subject to Time-Varying State Constraints. the Proposed Method Uses a Time-Varying Barrier Function to Accommodate the Constraints Leading to the Development of an Efficient Control Scheme. the Unknown Dynamics Are Approximated using a MNN, with Weights Tuned using a Singular Value Decomposition (SVD)-Based Technique. an Online Lifelong Learning (LL) based Elastic Weight Consolidation (EWC) Scheme is Also Incorporated to Alleviate the Issue of Catastrophic Forgetting. the Stability of the overall Closed-Loop System is Analyzed using Lyapunov Analysis. the …

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Decomposition Measurement For Antenna Gain And Radio Sensitivity Of Wireless Receiving System, Chaoqiang Zang, Lidong Chi, Fuhai Li, James L. Drewniak, Gang Feng, Yihong Qi Jan 2023

Decomposition Measurement For Antenna Gain And Radio Sensitivity Of Wireless Receiving System, Chaoqiang Zang, Lidong Chi, Fuhai Li, James L. Drewniak, Gang Feng, Yihong Qi

Electrical and Computer Engineering Faculty Research & Creative Works

A General Procedure for Decomposition Measurements for Receiver Antenna Gain and Radio Sensitivity based on Received Signal Strength Indicator (RSSI) Reporting is Proposed in This Paper. This Procedure Standardizes the Measurement Steps for Eliminating Nonlinear Error in RSSI Reporting. after Path Loss Calibration and RSSI Uncertainty Calibration, the Real Performance of the Antenna and the Radio Working in the Actual Environment of Wireless Receiving System Can Be Measured. the Antenna Gain is Obtained from the Difference between RSSI Reporting and Transmit Power, and the Radio Sensitivity is Obtained from the Transmit Power. This Method Helps to Improve the Development Efficiency …

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Oxidation Layer Formation On Aluminum Substrates With Surface Defects Using Molecular Dynamics Simulation, Emmanuel Olugbade, Hiep Pham, Yuchu He, Haicheng Zhou, Chulsoon Hwang, Jonghyun Park Jan 2023

Oxidation Layer Formation On Aluminum Substrates With Surface Defects Using Molecular Dynamics Simulation, Emmanuel Olugbade, Hiep Pham, Yuchu He, Haicheng Zhou, Chulsoon Hwang, Jonghyun Park

Electrical and Computer Engineering Faculty Research & Creative Works

Aluminum Oxide Layer Affects the Integrity of Electrical Contact and Can Contribute Adversely to Passive Intermodulation (PIM) Behavior in Radio Frequency (RF) Devices, necessitating a Need for Understanding its Formation Mechanism and Realistic Estimation of its Thickness. using ReaxFF Molecular Dynamics Simulation Technique, This Study Investigated the Impact of Surface Defects on Aluminum Oxide Layer Formation. Results Reveal that Crystallographic Orientation Did Not Affect the Kinetics of Oxidation Process of Aluminum. However, the Reaction Kinetics Increased Significantly with Surface Inhomogeneities Such as Cracks, Scratches, and Grain Boundaries. a Non-Uniform Oxide Layer with Thickness Variation in the Range of 72-77% Was …

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Augmented Genetic Algorithm V2 With Reinforcement Learning For Pdn Decap Optimization, Haran Manoharan, Jack Juang, Hanfeng Wang, Jingnan Pan, Kelvin Qiu, Xu Gao, Chulsoon Hwang Jan 2023

Augmented Genetic Algorithm V2 With Reinforcement Learning For Pdn Decap Optimization, Haran Manoharan, Jack Juang, Hanfeng Wang, Jingnan Pan, Kelvin Qiu, Xu Gao, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Genetic Algorithms (GAs) Use Many Hyperparameters, and Tuning These Parameters Can Determine the Optimization Performance. a GA with an Augmented Initial Population Was Proposed for Decap Optimization but It Had Convergence Issues by Getting Stuck in the Local Minimum. This Work Uses a Reinforcement Learning (RL) Approach to Adaptively Tune the Hyperparameters of GA during its Operation. with This Approach, the Agent Tries to Change the Parameters So that the GA Does Not Get Stuck in the Local Minimum. the Proposed Method Combining the RL Agent and Augmented GA Showed Better Performance in Terms of Solution Quality and Time Cost. …

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Intelligent Control Schemes For Maximum Power Extraction From Photovoltaic Arrays Under Faults, Azhar Ul-Haq, Shah Fahad, Saba Gul, Rui Bo Jan 2023

Intelligent Control Schemes For Maximum Power Extraction From Photovoltaic Arrays Under Faults, Azhar Ul-Haq, Shah Fahad, Saba Gul, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

Investigation of power output from PV arrays under different fault conditions is an essential task to enhance performance of a photovoltaic system under all operating conditions. Significant reduction in power output can occur during various PV faults such as module disconnection, bypass diode failure, bridge fault, and short circuit fault under non-uniform shading conditions. These PV faults may cause several peaks in the characteristics curve of PV arrays, which can lead to failure of the MPPT control strategy. In fact, impact of a fault can differ depending on the type of PV array, and it can make the control of …

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Predicting Compressive Strength And Hydration Products Of Calcium Aluminate Cement Using Data-Driven Approach, Sai Akshay Ponduru, Taihao Han, Jie Huang, Aditya Kumar Jan 2023

Predicting Compressive Strength And Hydration Products Of Calcium Aluminate Cement Using Data-Driven Approach, Sai Akshay Ponduru, Taihao Han, Jie Huang, Aditya Kumar

Electrical and Computer Engineering Faculty Research & Creative Works

Calcium aluminate cement (CAC) has been explored as a sustainable alternative to Portland cement, the most widely used type of cement. However, the hydration reaction and mechanical properties of CAC can be influenced by various factors such as water content, Li2CO3 content, and age. Due to the complex interactions between the precursors in CAC, traditional analytical models have struggled to predict CAC binders' compressive strength and porosity accurately. To overcome this limitation, this study utilizes machine learning (ML) to predict the properties of CAC. The study begins by using thermodynamic simulations to determine the phase assemblages of …

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Cooperative Deep $Q$ -Learning Framework For Environments Providing Image Feedback, Krishnan Raghavan, Vignesh Narayanan, Sarangapani Jagannathan Jan 2023

Cooperative Deep $Q$ -Learning Framework For Environments Providing Image Feedback, Krishnan Raghavan, Vignesh Narayanan, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In This Article, We Address Two Key Challenges in Deep Reinforcement Learning (DRL) Setting, Sample Inefficiency and Slow Learning, with a Dual-Neural Network (NN)-Driven Learning Approach. in the Proposed Approach, We Use Two Deep NNs with Independent Initialization to Robustly Approximate the Action-Value Function in the Presence of Image Inputs. in Particular, We Develop a Temporal Difference (TD) Error-Driven Learning (EDL) Approach, Where We Introduce a Set of Linear Transformations of the TD Error to Directly Update the Parameters of Each Layer in the Deep NN. We Demonstrate Theoretically that the Cost Minimized by the EDL Regime is an Approximation …

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Analyzing Ground Motion Records With Cvi Fuzzy Art, Dustin Tanksley, Xinzhe Yuan, Genda Chen, Donald C. Wunsch Jan 2023

Analyzing Ground Motion Records With Cvi Fuzzy Art, Dustin Tanksley, Xinzhe Yuan, Genda Chen, Donald C. Wunsch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

This paper explores using Cluster Validity Indices Fuzzy Adaptative Resonance Theory (CVI Fuzzy ART) to cluster ground motion records (GMRs). Clustering the features extracted from a supervised network trained for predicting the structure damage results in less overfitting from the trained network. Using Cluster Validity Indices (CVIs) to evaluate the clustering gives feedback to how well the data is being classified, allowing further separation of the data. By using CVI Fuzzy ART in combination with features extracted from a trained Convolutional Neural Network (CNN), we were able to form additional clusters in the data. Within the primary clusters, accuracy was …

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Area Average Surface Transfer Coefficient In Unit Cell Geometries, Benjamin Gabriel Mackey Jan 2023

Area Average Surface Transfer Coefficient In Unit Cell Geometries, Benjamin Gabriel Mackey

Masters Theses

"Honeycombs, metal foams, and lattice structures all provide a way to increase heat transfer due to better fluid mixing and larger surface area. Specifically, lattice structures can be a great way to provide heat transfer enhancement due to the ability to customize and optimize the unit cell geometry. In this research, a novel yet simple unit cell geometry is chosen for study. Four different configurations are tested in a lower Reynolds number range, 300–1800: single unit cell, two-unit cells in series, three-unit cells in series, and a 3x3 unit cell array. The Sherwood number of each configuration is found by …

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Guest Editor’S Introduction April 2023, Amy M. Belfi Jan 2023

Guest Editor’S Introduction April 2023, Amy M. Belfi

Psychological Science Faculty Research & Creative Works

One of the most commonly reported reasons for listening to music is simply because people find it enjoyable (Sanflippo et al., 2020). Despite aesthetic appreciation playing an important role in the motivation to listen to music, aesthetic responses to music have not been investigated as frequently as in other types of artistic modalities. This is perhaps due to the history of the field of music perception and cognition, which has traditionally focused more on basic perceptual functions and components of music, such as perception of pitch and rhythm, rather than aesthetic aspects of music listening. At this point, the study …

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Comparing Music- And Food-Evoked Autobiographical Memories In Young And Older Adults: A Diary Study, Kelly Jakubowski, Amy M. Belfi, Lia Kvavilashvili, Abbigail Ely, Mark Gill, Gemma Herbert Jan 2023

Comparing Music- And Food-Evoked Autobiographical Memories In Young And Older Adults: A Diary Study, Kelly Jakubowski, Amy M. Belfi, Lia Kvavilashvili, Abbigail Ely, Mark Gill, Gemma Herbert

Psychological Science Faculty Research & Creative Works

Previous Research Has Found that Music Brings Back More Vivid and Emotional Autobiographical Memories Than Various Other Retrieval Cues. However, Such Studies Have Often Been Low in Ecological Validity and Constrained by Relatively Limited Cue Selection and Predominantly Young Adult Samples. Here, We Compared Music to Food as Cues for Autobiographical Memories in Everyday Life in Young and Older Adults. in Two Separate Four-Day Periods, 39 Younger (Ages 18–34) and 39 Older (Ages 60–77) Adults Recorded their Music- and Food-Evoked Autobiographical Memories in Paper Diaries. Across Both Age Groups, Music Triggered More Frequent Autobiographical Memories, a Greater Proportion of Involuntary …

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Distinct Element Analysis Of Various Structural Element Responses For Coal Rib Support Simulation, A. Kirmaci, D. Guner, K. Karadeniz, Taghi Sherizadeh Jan 2023

Distinct Element Analysis Of Various Structural Element Responses For Coal Rib Support Simulation, A. Kirmaci, D. Guner, K. Karadeniz, Taghi Sherizadeh

Mining Engineering Faculty Research & Creative Works

Understanding the bolt responses for the efficacy of bolt performance during coal rib support applications plays a key role in controlling the stability of underground coal mine openings. Conducting pull-out tests is imperative to gain a better understanding of these responses. Field conditions such as block volume and degree of cleating may significantly impact bolt performance. These field conditions can be efficiently implemented in numerical modeling approaches, and selecting a proper structural element type for these numerical studies is crucial. This study developed a pull-out test model and compared the performance of structural elements as support members in the coal …

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Perspectives On Usability Testing With Iot Devices In Technical Communication Courses, David Wright Jan 2023

Perspectives On Usability Testing With Iot Devices In Technical Communication Courses, David Wright

English and Technical Communication Faculty Research & Creative Works

This Article Offers Perspectives on Adopting Smart Home Technology into Usability Testing for Technical and Professional Communication (TPC) Courses. Usability is a Valued Skill for Technical Communicators. However, Usability Testing Methods Have their Problems as Pedagogical Tools. Internet-Of-Things (IoT) Devices and Smart Home Technology (SHT) May Offer Instructors Tools to overcome Some of Those Problems. This Article Details Advantages and Concerns Associated with using SHT for Curricular Usability Testing.

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Making A Case For Political Technical Communication (Pxtc), Ryan Cheek Jan 2023

Making A Case For Political Technical Communication (Pxtc), Ryan Cheek

English and Technical Communication Faculty Research & Creative Works

In This Article, I Argue that the Accelerated Adoption of Political Technology during the COVID-19 Pandemic Evinces Exigency for a Rhetorically Grounded Framework to Teach, Research, and Practice Political Technical Communication (PxTC) as a Sub-Discipline. as a Starting Point, I Use a Rhetorical Genre Studies Approach to Identify Political Social Actions that Separate Political Communication Technologies into Four Distinct Genres: Election, Electioneering, Constituent Services, and Punditry.

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Decentralized And Coordinated V-F Control For Islanded Microgrids Considering Der Inadequacy And Demand Control, Buxin She, Fangxing Li, Hantao Cui, Jinning Wang, Liang Min, Oroghene Oboreh-Snapps, Rui Bo Jan 2023

Decentralized And Coordinated V-F Control For Islanded Microgrids Considering Der Inadequacy And Demand Control, Buxin She, Fangxing Li, Hantao Cui, Jinning Wang, Liang Min, Oroghene Oboreh-Snapps, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Proposes a Decentralized and Coordinated Voltage and Frequency (V-F) Control Framework for Islanded Microgrids, with Full Consideration of the Limited Capacity of Distributed Energy Resources (DERs) and V-F Dependent Load. First, the Concept of DER Inadequacy is Illustrated with the Challenges It Poses. Then, a Decentralized and Coordinated Control Framework is Proposed to Regulate the Output of Inverter-Based Generations and Reallocate Limited DER Capacity for V-F Control. the Control Framework is Composed of a Power Regulator and a V-F Regulator, Which Generates the Supplementary Signals for the Primary Controller. the Power Regulator Regulates the Output of Grid-Forming Inverters …

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System Level Pdn Impedance Optimization Utilizing The Zeros Of The Decoupling Capacitors, Yifan Ding, Shuang Liang, Francesco De Paulis, Matteo Cocchini, Samuel Connor, Matthew Doyle, Albert E. Ruehli, Chulsoon Hwang, James L. Drewniak Jan 2023

System Level Pdn Impedance Optimization Utilizing The Zeros Of The Decoupling Capacitors, Yifan Ding, Shuang Liang, Francesco De Paulis, Matteo Cocchini, Samuel Connor, Matthew Doyle, Albert E. Ruehli, Chulsoon Hwang, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

System-Level Power Distribution Network (PDN) Impedance Optimization Utilizing the Zeros of the Decoupling Capacitors (Decaps) is Discussed in This Paper. an Example of a Practical PDN Application is Proposed to Validate the Poles and Zeros Algorithm (P&Z) Presented. the System-Level PDN is with the Printed Circuit Board (PCB), Package (PKG), and Chip, as Well as the Low-Frequency Decaps on the PCB and the On-PKG Decoupling Capacitors. the PDN Optimization Results Are Compared with Those from the Genetic Algorithm (GA) to Show the Reasonableness and Validity of the P&Z Algorithm.

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Design And Construction Of An Arbitrary Pulse Compressive Amplifier, Cody Goins, Aaron Harmon, Victor Khilkevich, Daryl G. Beetner Jan 2023

Design And Construction Of An Arbitrary Pulse Compressive Amplifier, Cody Goins, Aaron Harmon, Victor Khilkevich, Daryl G. Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

Compressive Pulse Amplifiers Are a Class of Amplifiers that Convert Long Low Amplitude Signals into Very Broadband Pulses of High Amplitude, Yielding a Very High Instantaneous Peak Power Output Pulse. However, in the Realm of Electronic Immunity and Susceptibility Testing, Very Broadband Short Pulses Are Not Always Desired. This Work Presents a Design for a Compressive Amplifier that is Aimed at Creating Arbitrary Pulsed Signals of Varying Bandwidths. Limitations of the Achievable Gain and Methods Used Are Discussed.

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Characterization Of Virgin, Re-Used, And Oxygen-Reduced Copper Powders Processed By The Plasma Spheroidization Process, M. Hossein Sehhat, David Perez-Palomino, Connor Wiedemeier, Tristan Cullom, Joseph William Newkirk Jan 2023

Characterization Of Virgin, Re-Used, And Oxygen-Reduced Copper Powders Processed By The Plasma Spheroidization Process, M. Hossein Sehhat, David Perez-Palomino, Connor Wiedemeier, Tristan Cullom, Joseph William Newkirk

Mathematics and Statistics Faculty Research & Creative Works

Fabrication of parts with high mechanical properties heavily depend on the quality of powder deployed in the fabrication process. Copper powder in three different powder types were spheroidized using radio-frequency inductively coupled plasma (ICP) spheroidization process (TekSphero-15 system). The characterized powders include virgin powder as purchased from the powder manufacturer, powder used in electron beam powder bed fusion (EB-PBF) process, and reconditioned powder, which was used powder that underwent an oxygen-reduction treatment. The goal of spheroidizing these powder types was to evaluate the change in powder morphology, the possibility of enhancing the powder properties back to their as-received conditions, and …

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Delivering Broadband Light Deep Into Diffusive Media, Rohin Mcintosh, Nicholas Bender, Alexey Yamilov, Arthur Goetschy, Chia Wei Hsu, Hasan Yilmaz, Hui Cao Jan 2023

Delivering Broadband Light Deep Into Diffusive Media, Rohin Mcintosh, Nicholas Bender, Alexey Yamilov, Arthur Goetschy, Chia Wei Hsu, Hasan Yilmaz, Hui Cao

Physics Faculty Research & Creative Works

Waves propagate diffusively through disordered media, such as biological tissue, clouds, and paint, due to random scattering. Recent advances in optical wavefront shaping techniques have enabled controlling coherent light propagation in multiple-scattering samples. We overcome wave diffusion to deliver optical energy into a target region of arbitrary size and shape anywhere inside a strong-scattering system. This is particularly important for applications such as photoacoustic microscopy and optogenetics, where light needs to be deposited deep into biological tissue. For monochromatic light, we previously introduced the deposition matrix (DM) Z(ω), which maps its input wavefront to the field distribution in the target …

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Predicting Dissolution Kinetics Of Tricalcium Silicate Using Deep Learning And Analytical Models, Taihao Han, Sai Akshay Ponduru, Arianit Reka, Jie Huang, Gaurav Sant, Aditya Kumar Jan 2023

Predicting Dissolution Kinetics Of Tricalcium Silicate Using Deep Learning And Analytical Models, Taihao Han, Sai Akshay Ponduru, Arianit Reka, Jie Huang, Gaurav Sant, Aditya Kumar

Electrical and Computer Engineering Faculty Research & Creative Works

The dissolution kinetics of Portland cement is a critical factor in controlling the hydration reaction and improving the performance of concrete. Tricalcium silicate (C3S), the primary phase in Portland cement, is known to have complex dissolution mechanisms that involve multiple reactions and changes to particle surfaces. As a result, current analytical models are unable to accurately predict the dissolution kinetics of C3S in various solvents when it is undersaturated with respect to the solvent. This paper employs the deep forest (DF) model to predict the dissolution rate of C3S in the undersaturated solvent. The …

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Experimental Study For Improving The Productivity Of Laser Foil Printing, Tunay Turk, Ming-Chuan Leu Jan 2023

Experimental Study For Improving The Productivity Of Laser Foil Printing, Tunay Turk, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

This Study Aims to Improve the Productivity of Laser Foil Printing (LFP), Which is a Foil-Based Metal Additive Manufacturing (AM) Process. LFP Uses a Dual-Laser System to Fabricate a 3-Dimensional Part in a Layered Fashion by Performing Four Steps in Each Layer: Spot Welding, Pattern Welding, Contour Cutting, and Edge Polishing, All of Which Performed by Use of Lasers. We Experimentally Examined the Welding and Polishing Steps in This Study to Enhance LFP Productivity. the Jump Speed, Dwelling Duration, and Weld Path of Spot Welding and the Line Welding Speed and Wait Time between Weld Lines of Pattern Welding Are …

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Comparative Study Of Proppant Transport In The Vertical Fracture For High Viscosity Friction Reducers And Slickwater Fracturing With High-Tds Marcellus Shale Formation Water, Xiaojing Ge, Abdulmohsin Imqam, Baojun Bai Jan 2023

Comparative Study Of Proppant Transport In The Vertical Fracture For High Viscosity Friction Reducers And Slickwater Fracturing With High-Tds Marcellus Shale Formation Water, Xiaojing Ge, Abdulmohsin Imqam, Baojun Bai

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

High viscosity friction reducers (HVFRs) have been gaining more attention and increasing in use as proppant carriers. Reusing of produced water has also been driven by both environmental and economic benefits. However, high total dissolved solids (TDS) of produced water and high reservoir temperature significantly decrease the viscoelastic properties of HVFRs even for the cationic ones, which further reduce their proppant transport capabilities. Increasing loadings of HVFRs also has very limited effects on improving their proppant transport performances under high-TDS and high-Temperature conditions. The ultimate objective of this experimental study is to investigate the injection rate effects on the proppant …

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Promoting Enhanced Decision-Making And Proactive Management For Modularization In The Construction Industry Using Risk-Based Approach, Analytical Hierarchy Process, And Graph Theory, Mohamad Abdul Nabi Jan 2023

Promoting Enhanced Decision-Making And Proactive Management For Modularization In The Construction Industry Using Risk-Based Approach, Analytical Hierarchy Process, And Graph Theory, Mohamad Abdul Nabi

Doctoral Dissertations

"Modularization is an approach that can potentially mitigate many of the current construction industry’s challenges. Despite the documented advantages of modularization, the industry is still not able to capitalize on its full potential and benefits. The latter is due to the outdated decision-making models that may not reflect the multiple factors involved in modular construction, the unique source of risks associated with modular construction methods, need for continuous improvement, and complex contractual requirements and disputes. As such, the goal is to promote the use of modularization in the construction industry by enhancing decision-making and proactive risk management. The associated objectives …

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Recurrent Event Data Analysis With Mismeasured Covariates, Ravinath Alahakoon Mudiyanselage Jan 2023

Recurrent Event Data Analysis With Mismeasured Covariates, Ravinath Alahakoon Mudiyanselage

Doctoral Dissertations

"Consider a study with n units wherein every unit is monitored for the occurrence of an event that can recur with random end of monitoring. At each recurrence, p concomitant variables associated to the event recurrence are recorded with q (q ≤ p) collected with errors. Of interest in this dissertation is the estimation of the regression parameters of event time regression models accounting for the covariates. To circumvent the problem of bias and consistency associated with model's parameter estimation in the presence of measurement errors, we propose inference for corrected estimating functions with well-behaved roots under additive measurement errors …

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A Comprehensive Review Of The Influence Of Heat Exchange Tubes On Hydrodynamic, Heat, And Mass Transfer In Bubble And Slurry Bubble Columns, Dalia S. Makki, Hasan Sh Majdi, Amer A. Abdulrahman, Abbas J. Sultan, Zahraa W. Hasan, Laith S. Sabri, Bashar J. Kadhim, Muthanna H. Al-Dahhan Jan 2023

A Comprehensive Review Of The Influence Of Heat Exchange Tubes On Hydrodynamic, Heat, And Mass Transfer In Bubble And Slurry Bubble Columns, Dalia S. Makki, Hasan Sh Majdi, Amer A. Abdulrahman, Abbas J. Sultan, Zahraa W. Hasan, Laith S. Sabri, Bashar J. Kadhim, Muthanna H. Al-Dahhan

Chemical and Biochemical Engineering Faculty Research & Creative Works

Bubble and slurry bubble column reactors (BCRs/SBCRs) are used for various chemical, biochemical, and petrochemical applications. They have several operational and maintenance advantages, including excellent heat and mass transfer rates, simplicity, and low operating and maintenance cost. Typically, a catalyst is present in addition to biochemical processes where microorganisms are used to produce industrially valuable bio-products. Since most applications involve complicated gas-liquid, gas-liquid-solid, and exothermic processes, the BCR/SBCR must be equipped with heat-exchanging tubes to dissipate heat and control the reactor's overall performance. In this review, past and very recent experimental and numerical investigations on such systems are critically discussed. …

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Effect Of Alkali Metal Functionalization On Hydrogen Storage Performance Of Highly Porous Activated Carbons, Ruthradharshini Murugavel, Ali A. Rownaghi, Fateme Rezaei Jan 2023

Effect Of Alkali Metal Functionalization On Hydrogen Storage Performance Of Highly Porous Activated Carbons, Ruthradharshini Murugavel, Ali A. Rownaghi, Fateme Rezaei

Chemical and Biochemical Engineering Faculty Research & Creative Works

With increasing energy demand and fast-paced decarbonization methods adopted to curb the adverse effects of greenhouse gas emissions, hydrogen (H2) is considered a sustainable, clean, and potential renewable energy carrier for the future. To substitute the energy needs required for the physical methods of H2 storage, adsorbed gas storage (AGS) is the next viable option that provides the opportunity to adsorb and desorb gases under mild conditions. In this work, we studied the effect of light alkali metal functionalization comprising Li and K on the H2 storage performance of porous graphitic carbon adsorbents. The effect of metal doping on the …

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Analyzing Spatio-Temporal Mechanisms Of Land Subsidence In The Parowan Valley, Utah, Usa, Jiawei Li, Ryan G. Smith, Katherine R. Grote Jan 2023

Analyzing Spatio-Temporal Mechanisms Of Land Subsidence In The Parowan Valley, Utah, Usa, Jiawei Li, Ryan G. Smith, Katherine R. Grote

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Parowan Valley, Utah (USA), is an agricultural region experiencing rapid subsidence due to extensive groundwater extraction from aquifers with a significant portion of fine-grained sediments. To analyze the subsidence spatio-temporally, time-series Interferometric Synthetic Aperture Radar (InSAR) of 155 Sentinel-1 C-band scenes were processed. These data showed approximately 30 cm of ground subsidence in Parowan Valley from 2014 to 2020. Because of the high temporal sampling rate of the Sentinel-1 satellite (12-day cycle), it is possible to determine the seasonal changes of ground deformation and relate this to groundwater extraction. To better understand the relationship between ground deformation and groundwater extraction …

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