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Rafid: A Lightweight Approach To Radio Frequency Interference Detection In Time Domain Using Lstm And Statistical Analysis, Luke A. Smith, Vishesh Kumar Tanwar, Maciej Jan Zawodniok, Sanjay Kumar Madria Jan 2023

Rafid: A Lightweight Approach To Radio Frequency Interference Detection In Time Domain Using Lstm And Statistical Analysis, Luke A. Smith, Vishesh Kumar Tanwar, Maciej Jan Zawodniok, Sanjay Kumar Madria

Electrical and Computer Engineering Faculty Research & Creative Works

Recently, the utilization of Radio Frequency (RF) devices has increased exponentially over numerous vertical platforms. This rise has led to an abundance of Radio Frequency Interference (RFI) continues to plague RF systems today. The continued crowding of the RF spectrum makes RFI efficient and lightweight mitigation critical. Detecting and localizing the interfering signals is the foremost step for mitigating RFI concerns. Addressing these challenges, we propose a novel and lightweight approach, namely RaFID, to detect and locate the RFI by incorporating deep neural networks (DNNs) and statistical analysis via batch-wise mean aggregation and standard deviation (SD) calculations. RaFID investigates the …

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Analysis On The Effect Of Averaging Duration On Radio Frequency Dosimetry In Residential Environments, Reza Asadi, Hadi Aliakbarian, Amir Sahraei, Reza Yazdani, Donghyun Kim Jan 2023

Analysis On The Effect Of Averaging Duration On Radio Frequency Dosimetry In Residential Environments, Reza Asadi, Hadi Aliakbarian, Amir Sahraei, Reza Yazdani, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

The Potential Hazards of Electromagnetic Waves Have Raised Concerns in Related Authorities to Propose Standards and Limit Lines on the Electromagnetic Field Levels. Most of the Radio Frequency (RF) Dosimetry Measurement Procedures Referred to in Safety Compliance Standards, suggest 6-Minute Averaging, in Addition to Spatial Averaging, Which Can Be Time-Consuming for Primary Measurements. Measurement Analysis in Residential Environment in This Paper Demonstrates that Lowering the Time Interval of Measurements to About 30 Seconds, Which Suggests the Possibility of Reducing the Measurement Time with Minimal Reduction to Measurement Accuracy. for All Measurement Results Shown in This Paper, having a 30-Second Averaging …

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Continual Learning-Based Optimal Output Tracking Of Nonlinear Discrete-Time Systems With Constraints: Application To Safe Cargo Transfer, Behzad Farzanegan, S. (Sarangapani) Jagannathan Jan 2023

Continual Learning-Based Optimal Output Tracking Of Nonlinear Discrete-Time Systems With Constraints: Application To Safe Cargo Transfer, Behzad Farzanegan, S. (Sarangapani) Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Addresses a Novel Lifelong Learning (LL)-Based Optimal Output Tracking Control of Uncertain Non-Linear Affine Discrete-Time Systems (DT) with State Constraints. First, to Deal with Optimal Tracking and Reduce the Steady State Error, a Novel Augmented System, Including Tracking Error and its Integral Value and Desired Trajectory, is Proposed. to Guarantee Safety, an Asymmetric Barrier Function (BF) is Incorporated into the Utility Function to Keep the Tracking Error in a Safe Region. Then, an Adaptive Neural Network (NN) Observer is Employed to Estimate the State Vector and the Control Input Matrix of the Uncertain Nonlinear System. Next, an NN-Based …

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Analysis On Extraction Of Potential Radiated Emission Limit Line For Data Center Equipment From 10 Ghz To 40 Ghz, Zhekun Peng, Wei Zhang, Jong Hwa Kwon, Donghyun Kim Jan 2023

Analysis On Extraction Of Potential Radiated Emission Limit Line For Data Center Equipment From 10 Ghz To 40 Ghz, Zhekun Peng, Wei Zhang, Jong Hwa Kwon, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

The Radiated Emission (RE) Potential Limit Line for Router System is Analyzed from 10 GHz to 40 GHz based on CISPR TR 16-4-4 Standard. Statistical Data is Collected for the Limit Line Extraction from Measurement, Numerical Analysis, 3D Full-Wave Simulation and Literature Studies. All the Factors Considered in Limit Line Calculation Are Analyzed for Data Center Equipment Operation. the Result of Extracted Potential Limit Line Shows the Rising Limit Line between 10 GHz and 40 GHz Frequency Band for Potential Future Radiated Emission Limit Line above 40 GHz Targeted for High-Speed Equipment Radiated Emission. This Paper is Not a Standard …

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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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Reconfigurable Intelligent Surface (Ris) Design For 5g N260 Frequency Band, Reza Yazdani, Manish Kizhakkeveettil Mathew, Zhekun Peng, Donghyun Kim Jan 2023

Reconfigurable Intelligent Surface (Ris) Design For 5g N260 Frequency Band, Reza Yazdani, Manish Kizhakkeveettil Mathew, Zhekun Peng, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

In This Paper, a New Low Profile Reconfigurable Intelligent Surface Design with High Resolution Steering Reflector and Wide Frequency Band Width is Proposed at N260 Frequency Band, Used for 5G New Radio Applications. the Dynamic Reflection Phase and Tunability is Realized by Integrating of Varactor Diode with Each Unit Cell. This Study Presents Design Procedures, Reflection Simulation Verifications, and the Effects of Important Parameters on the Performance of the Proposed Novel Resonant Unit Cell. the Proposed Unit Cell Offers a Dynamic Reflection Phase Range of More Than 270° at a Wide Frequency Bandwidth. Simulation Results of Beam Steering Capability in …

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Esd Behavior Of Rf Switches And Importance Of System Efficient Esd Design, Seyed Mostafa Mousavi, Emil Tauber, Amin Pak, David Pommerenke, Daryl G. Beetner, Ketan Shringarpure, Benjamin Lee, Warwick Ka Kui Wong Jan 2023

Esd Behavior Of Rf Switches And Importance Of System Efficient Esd Design, Seyed Mostafa Mousavi, Emil Tauber, Amin Pak, David Pommerenke, Daryl G. Beetner, Ketan Shringarpure, Benjamin Lee, Warwick Ka Kui Wong

Electrical and Computer Engineering Faculty Research & Creative Works

RF Switches Are Typically Used in the RF Front-End of Portable Devices Such as Antenna or Matching Tuners to Improve the RF Link Performance. They Are Usually the First Active Devices after the Antenna and Are Vulnerable to Primary or Secondary ESD Discharges to the Antennas. This Paper Investigates the ESD Behavior of One of the High Frequency Switches Used in the RF-Front-End of Portable Devices and Expresses the Importance of the ESD Pulse that Passes through the Switch and Reaches the Next Stage in the RF Path, Possibly Damaging the Next Stage.

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Coupling Path Analysis For Smart Speaker Intentional Electromagnetic Interference Attacks, Tanner Fokkens, Shengxuan Xia, Aaron Harmon, Chulsoon Hwang Jan 2023

Coupling Path Analysis For Smart Speaker Intentional Electromagnetic Interference Attacks, Tanner Fokkens, Shengxuan Xia, Aaron Harmon, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

This Paper Shows an Improved Understanding of the Coupling Path for Intentional Electromagnetic Interference (IEMI) Attacks on Smart Speaker Devices. This Includes a Method for Finding the Ideal Attack Angle and Locating the Region Sensitive to the Coupled EMI. in Previous Works, It Was Shown to Be Possible to Send RF Commands to a Smart Speaker and Have These Commands Be Interpreted as Voice Commands by the Microphone. However, the Attack Still Had Some Limited Understanding in Terms of the Coupling Path Location and Long-Distance Attack Potential. using the Improved Understanding of the Attack, a Longer Attack Distance is Achieved …

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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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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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Virtual Inertia Scheduling (Vis) For Real-Time Economic Dispatch Of Ibrs-Penetrated Power Systems, Buxin She, Fangxing Li, Hantao Cui, Jinning Wang, Qiwei Zhang, Rui Bo Jan 2023

Virtual Inertia Scheduling (Vis) For Real-Time Economic Dispatch Of Ibrs-Penetrated Power Systems, Buxin She, Fangxing Li, Hantao Cui, Jinning Wang, Qiwei Zhang, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

A New Concept Called Virtual Inertia Scheduling (VIS) is Proposed to Efficiently Handle the Increasing Penetration of Inverter-Based Resources (IBRs) in Power Systems. VIS is an Inertia Management Framework that Targets Security-Constrained and Economy-Oriented Inertia Scheduling and Generation Dispatch with a Large Scale of Renewable Generations. Specifically, It Determines the Appropriate Power Setting Points and Reserved Capacities of Synchronous Generators and IBRs, as Well as the Control Modes and Control Parameters of IBRs to Provide Secure and Cost-Effective Inertia Support. First, a Uniform System Model is Employed to Quantify the Frequency Dynamics of the IBRs-Penetrated Power Systems after Disturbances. Leveraging …

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Equivalent Force Extraction Methodology For Electrical Component Induced Pcb Vibration, Yifan Ding, Jianmin Zhang, Ming Feng Xue, Xin Hua, Benjamin Leung, Eric A. Macintosh, Chulsoon Hwang Jan 2023

Equivalent Force Extraction Methodology For Electrical Component Induced Pcb Vibration, Yifan Ding, Jianmin Zhang, Ming Feng Xue, Xin Hua, Benjamin Leung, Eric A. Macintosh, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

On-board electrical components can cause printed circuit board (PCB) vibration, thus generating audio noise if the electrical noise is in the audible frequency range. The electrical component-induced vibration can be equated to an external force applied to the PCB. This article presents a novel methodology to extract the equivalent force of electrical components on a PCB to study board vibration and potential acoustic noise problems. The method is based on a combination of measurement and simulation, wherein PCB vibration is used as the medium in the extraction process. The methodology is validated by the correlation of PCB vibration pattern, frequency, …

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Cascaded Sapphire Fiber Bragg Gratings Inscribed By Femtosecond Laser For Molten Steel Studies, Dinesh Reddy Alla, Deva Prasad Neelakandan, Farhan Mumtaz, Rex E. Gerald, Laura Bartlett, Ronald J. O'Malley, Jeffrey D. Smith, Jie Huang Jan 2023

Cascaded Sapphire Fiber Bragg Gratings Inscribed By Femtosecond Laser For Molten Steel Studies, Dinesh Reddy Alla, Deva Prasad Neelakandan, Farhan Mumtaz, Rex E. Gerald, Laura Bartlett, Ronald J. O'Malley, Jeffrey D. Smith, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

This research reports a distributed fiber optic high-temperature sensing system tailored for applications in the steel industry and various other sectors. Recent advancements in optical sensor technology have led to the exploration of sapphire crystal fibers as a solution for sensing in harsh environments. Utilizing a femtosecond (fs) laser, cascaded fiber Bragg gratings (FBGs) were meticulously fabricated within a multimode sapphire optical fiber. These FBGs endowed the system with distributed sensing capabilities and underwent rigorous testing under extreme temperatures, reaching up to 1,800 °C. The study delves into the investigation of the FBG reflection spectrum, facilitated by the development of …

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Deep-Learning-Based Accurate Beamforming Prediction Using Lidar-Assisted Network, Omar Rinchi, Ahmad Alsharoa, Ibrahem Shatnawi Jan 2023

Deep-Learning-Based Accurate Beamforming Prediction Using Lidar-Assisted Network, Omar Rinchi, Ahmad Alsharoa, Ibrahem Shatnawi

Electrical and Computer Engineering Faculty Research & Creative Works

Beamforming optimization can enhance the next-generation wireless networks. However, finding the optimal beamforming in real-time is hard due to the need for large beam training overhead. The problem can be more challenging in dynamic environments with small coherence channel time. In this paper, we propose an accurate beam prediction solution using light detection and ranging (LiDAR)-assisted radio frequency (RF) system. More specifically, we propose a deep-learning model based on long-sort term memory (LSTM) to predict future beam indices from a set of pre-defined beam steering codebook. In addition to solving the beamforming overhead problem, the proposed deep learning approach is …

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Conductive 3d Nano-Biohybrid Systems Based On Densified Carbon Nanotube Forests And Living Cells, Roya Bagheri, Alicia K. Ball, Masoud Kasraie, Aparna Chandra, Xinqian Chen, Ibrahim Miskioglu, Zhiying Shan, Parisa Pour Shahid Saeed Abadi Jan 2023

Conductive 3d Nano-Biohybrid Systems Based On Densified Carbon Nanotube Forests And Living Cells, Roya Bagheri, Alicia K. Ball, Masoud Kasraie, Aparna Chandra, Xinqian Chen, Ibrahim Miskioglu, Zhiying Shan, Parisa Pour Shahid Saeed Abadi

Michigan Tech Publications

Conductive biohybrid cell-material systems have applications in bioelectronics and biorobotics. To date, conductive scaffolds are limited to those with low electrical conductivity or 2D sheets. Here, 3D biohybrid conductive systems are developed using fibroblasts or cardiomyocytes integrated with carbon nanotube (CNT) forests that are densified due to interactions with a gelatin coating. CNT forest scaffolds with a height range of 120–240 µm and an average electrical conductivity of 0.6 S/cm are developed and shown to be cytocompatible as evidenced from greater than 89% viability measured by live-dead assay on both cells on day 1. The cells spread on top and …

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Garbage In, Garbage Out: A Theory-Driven Approach To Improve Data Handling In Supervised Machine Learning, Steven J. Hyde, Eric Bachura, Joseph S. Harrison Jan 2023

Garbage In, Garbage Out: A Theory-Driven Approach To Improve Data Handling In Supervised Machine Learning, Steven J. Hyde, Eric Bachura, Joseph S. Harrison

Boise State University Publications and Presentations

Machine learning (ML) has recently gained momentum as a method for measurement in strategy research. Yet, little guidance exists regarding how to appropriately apply the method for this purpose in our discipline. We address this by offering a guide to the application of ML in strategy research, with a particular emphasis on data handling practices that should improve our ability to accurately measure our constructs of interest using ML techniques. We offer a brief overview of ML methodologies that can be used for measurement before describing key challenges that exist when applying those methods for this purpose in strategy research …

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Fluorescence Lifetime Imaging Microscopy Of Biomolecular Condensates, My Diem Quan, Shih-Chu Jeff Liao, Josephine C Ferreon, Allan Chris M Ferreon Jan 2023

Fluorescence Lifetime Imaging Microscopy Of Biomolecular Condensates, My Diem Quan, Shih-Chu Jeff Liao, Josephine C Ferreon, Allan Chris M Ferreon

Faculty, Staff and Students Publications

Biomolecular condensates of ribonucleoproteins (RNPs) such as the transactivation response element (TAR) DNA-binding protein 43 (TDP-43) arise from liquid-liquid phase separation (LLPS) and play vital roles in various biological processes including the formation-dissolution of stress granules (SGs). These condensates are thought to be directly linked to neurodegenerative diseases, providing a depot of aggregation-prone proteins and serving as a cauldron of protein aggregation and fibrillation. Despite recent research efforts, biochemical processes and rearrangements within biomolecular condensates that trigger subsequent protein misfolding and aggregation remain to be elucidated. Fluorescence lifetime imaging microscopy (FLIM) provides a minimally intrusive high-sensitivity and high-resolution imaging method …

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Estimating Dementia Risk In An African American Population Using The Dctclock, Marissa Ciesla, Jeff Pobst, Joyce Gomes-Osman, Melissa Lamar, Lisa L Barnes, Russell Banks, Ali Jannati, David Libon, Rodney Swenson, Sean Tobyne, David Bates, John Showalter, Alvaro Pascual-Leone Jan 2023

Estimating Dementia Risk In An African American Population Using The Dctclock, Marissa Ciesla, Jeff Pobst, Joyce Gomes-Osman, Melissa Lamar, Lisa L Barnes, Russell Banks, Ali Jannati, David Libon, Rodney Swenson, Sean Tobyne, David Bates, John Showalter, Alvaro Pascual-Leone

Faculty, Staff and Students Publications

The prevalence of Alzheimer's disease (AD) and related dementias (ADRD) is increasing. African Americans are twice as likely to develop dementia than other ethnic populations. Traditional cognitive screening solutions lack the sensitivity to independently identify individuals at risk for cognitive decline. The DCTclock is a 3-min AI-enabled adaptation of the well-established clock drawing test. The DCTclock can estimate dementia risk for both general cognitive impairment and the presence of AD pathology. Here we performed a retrospective analysis to assess the performance of the DCTclock to estimate future conversion to ADRD in African American participants from the Rush Alzheimer's Disease Research …

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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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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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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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Panel: Faculty Leadership, Lina Karam, Georges Zissis, Jason Yao, Jill Nelson, Minho Jo, Rafal Sliz, Michele Nogueira, Steve Watkins, Huihui Wang Jan 2023

Panel: Faculty Leadership, Lina Karam, Georges Zissis, Jason Yao, Jill Nelson, Minho Jo, Rafal Sliz, Michele Nogueira, Steve Watkins, Huihui Wang

Electrical and Computer Engineering Faculty Research & Creative Works

This faculty leadership panel will be held jointly by the IEEE Education Society (IEEE EdSoc) and IEEE Educational Activities Board (EAB) Faculty Resources Committee (FRC). The panel intends to provide participants introductory knowledge and skills. Two moderators and four panelists will focus on discussing their various academic leadership experiences and practices. The panel will be held in an interactive way so that the participants will have enough time to ask questions or communicate with the panelists. It is expected that this joint panel may potentially help to build up networks and mentorships.

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Microstructure, Mechanical Properties And Oxidation Behavior Of Refractory Multi-Principal Element Alloys By Laser Remelting And Conventional Manufacturing, Visharad Jalan, Seth Crawford, Sung Heng Wu, Frank W. Liou, Haiming Wen Jan 2023

Microstructure, Mechanical Properties And Oxidation Behavior Of Refractory Multi-Principal Element Alloys By Laser Remelting And Conventional Manufacturing, Visharad Jalan, Seth Crawford, Sung Heng Wu, Frank W. Liou, Haiming Wen

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Refractory Multi-Principal Element Alloys (RMPEAs), HfNbTaTiZr, (HfNbTaTiZr)9Cr, and (HfNbTaTiZr)9Al, Were Manufactured using Vacuum Arc Melting Followed by Laser Remelting to Mimic Additive Manufacturing. the Microhardness of the As-Cast HfNbTaTiZr, (HfNbTaTiZr)9Cr, and (HfNbTaTiZr)9Al Samples after Arc Melting Was Measured as 6.20, 7.63, and 6.89 Gpa, respectively. after Laser Remelting and Re-Solidification, the Hardness Increased by ~ 30% for Each Composition; the Hardest Was (HfNbTaTiZr)9Cr Measured at 9.60 GPa, While the Softest Was HfNbTaTiZr with a Hardness of 8.42 GPa, Which Was Still Harder Compared to All the Other Samples. the Addition …

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Application Of A Variable Path Length Repetitive Process Control For Direct Energy Deposition Of Thin-Walled Structures, Elias B. Snider, Douglas A. Bristow Jan 2023

Application Of A Variable Path Length Repetitive Process Control For Direct Energy Deposition Of Thin-Walled Structures, Elias B. Snider, Douglas A. Bristow

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Direct Energy Deposition (DED) Additive Manufacturing is Well Suited to Fabricating Large Thin-Walled Metal Structures Such as Rocket Nozzles but Suffers from Layer-To-Layer Defect Propagation. Propagating Defects May Exhibit as Slumping or a Ripple in Bead Geometry. Recent Works Have Used Repetitive Process Control (RPC) Methods for Additive Manufacturing to Stabilize the Layer-Wise Defect Propagation, But These Methods Require Repetition of the Same Path. However, Typical Thin-Wall DED Applications, Sometimes Referred to as Vase Structures, Have Changing Paths with Each Layer Such as Expanding or Contracting Diameters and Changing Profiles. This Paper Presents an Extension to Optimal RPC that Uses …

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Correction: Modeling Phase Selection And Extended Solubility In Rapid Solidified Alloys (Metallurgical And Materials Transactions A, (2023), 10.1007/S11661-023-07221-7), Azeez Akinbo, Yijia Gu Jan 2023

Correction: Modeling Phase Selection And Extended Solubility In Rapid Solidified Alloys (Metallurgical And Materials Transactions A, (2023), 10.1007/S11661-023-07221-7), Azeez Akinbo, Yijia Gu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In the original online version of this article the reference citation in Fig. 3b was incorrect. The original article was corrected.

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Thermal Diffusivity Materials Characterization Via Active Microwave Thermography, Logan M. Wilcox, Kristen M. Donnell Jan 2023

Thermal Diffusivity Materials Characterization Via Active Microwave Thermography, Logan M. Wilcox, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Active microwave thermography (AMT) is a relatively new nondestructive evaluation method which is proposed in this work for thermal materials characterization. Specifically, AMT is investigated as a single-sided measurement option for out-of-plane thermal diffusivity (a parameter traditionally measured using a two-sided technique). Simulation and measurement results support the use of AMT for such a characterization for materials backed by an electromagnetically absorptive material. Both lossless and lossy materials may be measured, with better accuracy for lossless materials. The effect of heating time was also considered. The results indicate that for the 50 W system used here, 100 seconds of electromagnetic …

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Observer-Based Model Predictive Control With Continuous Control Set For Single-Phase Rectifiers, Milad Dehghanzadeh, Rui Bo, Kamal Al-Haddad Jan 2023

Observer-Based Model Predictive Control With Continuous Control Set For Single-Phase Rectifiers, Milad Dehghanzadeh, Rui Bo, Kamal Al-Haddad

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a model predictive controller (MPC) is designed for a single-phase rectifier. The proposed MPC works with a continuous control set (CCS) that addresses variable switching issues in finite control set (FCS) MPCs. The observe-ability of the rectifier enables the design of a full-state observer to measure only output voltage in which the AC current of the rectifier is estimated. Both the proposed controller and observer are assessed with simulation studies and the results show the acceptable performance of the observer and CCS-MPC as well as good disturbance rejection in load and network parameter variations.

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Dipole-Moment-Based Reciprocity For Practical Desensitization Identification And Mitigation, Shengxuan Xia, Hanfeng Wang, Yansheng Wang, Zhonghua Wu, Chulsoon Hwang, Jun Fan Jan 2023

Dipole-Moment-Based Reciprocity For Practical Desensitization Identification And Mitigation, Shengxuan Xia, Hanfeng Wang, Yansheng Wang, Zhonghua Wu, Chulsoon Hwang, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Radio frequency interference can degrade the receiving sensitivity of antennas. The interference is usually caused by certain coupling structures, such as layouts without adequate grounding for the radio frequency signal return path. Those structures can be modeled as a set of equivalent dipole moments when they are electrically small. Herein, the dipole moment model-based coupling framework is applied to a practical cellphone design case to devise an engineering solution. The coupling framework incorporates dipole moments as radiation sources and a coupling model based on the reciprocity theorem. Unfortunately, near-field scan probes often lack access to all locations, owing to the …

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Managing Reserve Deliverability Risk Of Integrated Electricity-Heat Systems In Day-Ahead Market: A Distributionally Robust Joint Chance Constrained Approach, Yang Chen, Jianxue Wang, Siyuan Wang, Rui Bo, Chenjia Gu, Qingtao Li Jan 2023

Managing Reserve Deliverability Risk Of Integrated Electricity-Heat Systems In Day-Ahead Market: A Distributionally Robust Joint Chance Constrained Approach, Yang Chen, Jianxue Wang, Siyuan Wang, Rui Bo, Chenjia Gu, Qingtao Li

Electrical and Computer Engineering Faculty Research & Creative Works

The integrated electricity and heat system (IEHS) is an emerging demand-side flexible resource for power systems. IEHS operators participating in electricity markets considering their capabilities in reserve provision will face the reserve deliverability risk due to the energy-limited storage nature of heat systems. To address this challenge and increase profitability, a distributionally robust joint chance-constrained mechanism with enhanced quantifications is adopted for the heating system and reserve deployment uncertainties. Detailed pipeline storage representation for thermal networks and integrated demand response are incorporated into this strategic participation model. A two-stage distributionally robust joint chance constrained program is then incorporated to effectively …

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A Methodology For Predicting Acoustic Noise From Singing Capacitors In Mobile Devices, Xin Yan, Jianmin Zhang, Songping Wu, Ming Feng Xue, Chi Kin Benjamin Leung, Eric A. Macintosh, Daryl G. Beetner Jan 2023

A Methodology For Predicting Acoustic Noise From Singing Capacitors In Mobile Devices, Xin Yan, Jianmin Zhang, Songping Wu, Ming Feng Xue, Chi Kin Benjamin Leung, Eric A. Macintosh, Daryl G. Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

Multilayer ceramic capacitors (MLCCs) connected to a power distribution network (PDN) can create acoustic noise through a combination of the power rail noise at the MLCCs and the piezoelectric effect of the capacitor's ceramic material. The deformation of the MLCCs brought on by power supply noise creates vibrations which cause the printed circuit board (PCB) to vibrate and generate the audible acoustic noise. In the following paper, a simulation methodology is presented to analyze the acoustic noise created by MLCCs on a PCB. A simulation model for the PCB vibration modal response is built and the modal superposition method is …

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