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Electrical and Computer Engineering Faculty Research & Creative Works

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Full-Text Articles in Engineering

Pulsed-Active Microwave Thermography, Logan M. Wilcox, Mathias Bonmarin, Kristen M. Donnell Jan 2022

Pulsed-Active Microwave Thermography, Logan M. Wilcox, Mathias Bonmarin, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Active microwave thermography (AMT) is a thermographic nondestructive testing and evaluation technique that utilizes an electromagnetic-based excitation with a subsequent infrared measurement of the surface thermal profile of the material or structure of interest. AMT has been successfully applied to several aerospace and civil infrastructure applications. This work seeks to expand the performance of AMT by incorporating a signal processing technique common to traditional (flash-lamp) thermography, referred to as pulsed thermography (PT). PT operates on the premise of a pulsed excitation, as opposed to a constant or step excitation (ST) over a given time-period that is typical to traditional active …


A New Discontinuous Conduction Mode In A Transformer Coupled High Gain Dc-Dc Converter, Kartikeya J.P. Veeramraju, Jacob Eisen, Joshua L. Rovey, Jonathan W. Kimball Jan 2022

A New Discontinuous Conduction Mode In A Transformer Coupled High Gain Dc-Dc Converter, Kartikeya J.P. Veeramraju, Jacob Eisen, Joshua L. Rovey, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

Electrospray space propulsion thrusters often employ transformer coupled high gain dc-dc converters. These thrusters have a unique load resistance profile that can vary dramatically during operation. Transformer coupled high gain dc-dc converters working in very low power modes can enter a unique discontinuous conduction mode (DCM) caused by a coupling effect between the boost and magnetization inductors in the converter. The transformer magnetization current prevents the boost inductors from discharging properly, which causes premature loss of boost action and higher than expected boost inductor voltages. This mechanism generates abnormally high voltages on the converter's output side, leading to converter and …


New Hybrid Model For Evaluating The Frequency-Dependent Leakage Inductance Of A Variable Inductance Transformer (Vit), Angshuman Sharma, Jonathan W. Kimball Jan 2022

New Hybrid Model For Evaluating The Frequency-Dependent Leakage Inductance Of A Variable Inductance Transformer (Vit), Angshuman Sharma, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

Skin and proximity effects can cause a significant drop in the effective leakage inductance of a transformer when the operating frequency is increased. Although the magnetic image method-based double-2-D model can calculate the low-frequency leakage inductance with sufficient accuracy, it is inherently a frequency-independent model. While Dowell's 1-D model uses frequency-dependent relations to account for both skin and proximity effects, its accuracy is severely affected by the assumed winding geometry. In this paper, a hybrid model is proposed that uses superposition to combine a modified Dowell's model with the double-2-D model. The proposed model is investigated on a variable inductance …


Improving Virtual Synchronous Generator Control In Microgrids Using Fuzzy Logic Control, Oroghene Oboreh-Snapps, Rui Bo, Buxin She, Fangxing Fran Li, Hantao Cui Jan 2022

Improving Virtual Synchronous Generator Control In Microgrids Using Fuzzy Logic Control, Oroghene Oboreh-Snapps, Rui Bo, Buxin She, Fangxing Fran Li, Hantao Cui

Electrical and Computer Engineering Faculty Research & Creative Works

Virtual synchronous generators (VSG) are designed to mimic the inertia and damping characteristics of synchronous generators (SG), which can improve the frequency response of a microgrid. Unlike synchronous generators whose inertia and damping are restricted by the physical characteristics of the SG, VSG parameters can be more flexibly controlled to adapt to different disturbances. This paper therefore proposes a fuzzy logic controller designed to adaptively set the parameters of the VSG during a frequency event to ensure an improved frequency nadir and rate of change of frequency (ROCOF) response. The proposed control method is implemented and tested on the power …


A Dnn-Ensemble Method For Error Reduction And Training Data Selection In Dnn Based Modeling, Ling Zhang, Da Li, Jiayi He, Bhyrav Mutnury, Bo Pu, Xiao Ding Cai, Chulsoon Hwang, Jun Fan, James L. Drewniak, Er Ping Li Jan 2022

A Dnn-Ensemble Method For Error Reduction And Training Data Selection In Dnn Based Modeling, Ling Zhang, Da Li, Jiayi He, Bhyrav Mutnury, Bo Pu, Xiao Ding Cai, Chulsoon Hwang, Jun Fan, James L. Drewniak, Er Ping Li

Electrical and Computer Engineering Faculty Research & Creative Works

Deep neural networks (DNNs) have been widely adopted in modeling electromagnetic compatibility (EMC) problems, but the training data acquisition is usually time-consuming through various simulators. This paper presents a powerful approach using an ensemble of DNN s to effectively reduce the training data size in DNN-based modeling problems. A batch of training data with the largest uncertainties is selected using active learning through the variance among the ensemble of DNNs. Subsequently, a greedy sampling algorithm is applied to select a data subset using diversity. Thus, the proposed method can achieve both uncertainty and diversity in data selection. By averaging the …


A Segmentation Strategy For Structures With Common Mode Coupling, James Hunter, Shengxuan Xia, Aaron Harmon, Mohamed Z.M. Hamdalla, Ahmed M. Hassan, Victor Khilkevich, Daryl G. Beetner Jan 2022

A Segmentation Strategy For Structures With Common Mode Coupling, James Hunter, Shengxuan Xia, Aaron Harmon, Mohamed Z.M. Hamdalla, Ahmed M. Hassan, Victor Khilkevich, Daryl G. Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

The level of electromagnetic coupling to electronic devices can vary widely from one device to another. When considering the induced voltage from an incoming plane wave on printed circuit boards (PCBs) and their attached cable harnesses, there is significant variety in the configuration of the devices that could be seen. This encourages the use of segmentation, so that the components of these devices (PCBs, connectors, and harnesses) can be modeled separately to alleviate simulation burden. This allows for a more flexible model and a 'toolbox' to construct devices with. The goal of this work is to use segmentation to model …


High Permittivity Anisotropic 3d Printed Material, Aaron Harmon, Victor Khilkevich, Kristen M. Donnell Jan 2022

High Permittivity Anisotropic 3d Printed Material, Aaron Harmon, Victor Khilkevich, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, the diagonal elements of the permittivity matrix for dielectric samples, 3D printed with a carbon fiber-loaded material (XT-CF20), are measured for frequencies within the range of 1 MHz to 18 GHz. These permittivity measurements demonstrated a strong anisotropy, indicating that the electromagnetic properties of the CF20 material depend on the infill method used to print. The importance of understanding the anisotropy for microwave device design is demonstrated via a dielectric-loaded cavity resonator application.


Practical Fixture Design For Passive Intermodulation Tests For Flexible Metallic Contacts, Shengxuan Xia, Yuchu He, Yansheng Wang, Hanfeng Wang, George Mankaruse, Danny Chan, Haicheng Zhou, Warren Lee, Nicholas Mcdonnell, Chulsoon Hwang Jan 2022

Practical Fixture Design For Passive Intermodulation Tests For Flexible Metallic Contacts, Shengxuan Xia, Yuchu He, Yansheng Wang, Hanfeng Wang, George Mankaruse, Danny Chan, Haicheng Zhou, Warren Lee, Nicholas Mcdonnell, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Passive intermodulation (PIM) commonly exists in non-ideal metallic contacts. Since PIM typically represents an extremely low level of nonlinearity, it has not drawn enough attention over the years except for extremely high-power applications such as base stations. However, in recent years, the study on PIM has become essential in universally used consumer electronics design because of the higher requirement on the radio frequency (RF) sensitivity of wireless communications. The metal contacts caused PIM can create the sideband spectrum to interfere with the receiving band in the frequency divide duplex (FDD) mode. Therefore, the study on PIM for the frequently used …


Peec-Based On-Chip Pdn Impedance Modeling Using Layered Green's Function, Chaofeng Li, Biyao Zhao, Bo Pu, Xu Wang, Donghyun Kim, Jun Fan Jan 2022

Peec-Based On-Chip Pdn Impedance Modeling Using Layered Green's Function, Chaofeng Li, Biyao Zhao, Bo Pu, Xu Wang, Donghyun Kim, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents an impedance model of on-chip power distribution network (PDN), which is an efficient criterion for estimating simultaneous switching noises (SSNs) on 3-D integrated circuit (IC). The impedance of on-chip PDN, including the effect of silicon substrate, is accurately modeled based on partial element equivalent circuit (PEEC) and layered Green's function (LGF). The equivalent circuit model of PDN is extracted based on the physical dimensions and electrical material characteristic of PDN at first. And then the LGF is used to consider the effect of silicon substrate for improving the accuracy of on-chip PDN impedance model. The effectiveness of …


Analysis Of Switching Voltage Regulator Noise Coupling To A High-Speed Signal, Junho Joo, Soumya Singh, P. K. Seema, Chulsoon Hwang, Bhyrav Mutnury, James L. Drewniak Jan 2022

Analysis Of Switching Voltage Regulator Noise Coupling To A High-Speed Signal, Junho Joo, Soumya Singh, P. K. Seema, Chulsoon Hwang, Bhyrav Mutnury, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a real-world signal and power integrity problem due to the switching noise of buck converter IC coupling to a high-speed signal line in a server system is studied. The rapid switching field effect transistors (FETs) of the voltage regulator module (VRM) are the main source of the performance degradation on the nearby signal lines. A simplified mock-up simulation setup is proposed based on the actual board design to investigate the coupling mechanism of the VRM noise. The mechanism of the switching noise coupling is explained with the phenomenon of capacitive and inductive coupling. Based on this finding, …


Optimizing The Placement Of Non-Functional Pads On Signal Vias Using Multiple Reflection Analysis, Muqi Ouyang, Kevin Cai, Chaofeng Li, Anna Gao, Felen Fu, Hannah Bian, Bidyut Sen, Donghyun Kim Jan 2022

Optimizing The Placement Of Non-Functional Pads On Signal Vias Using Multiple Reflection Analysis, Muqi Ouyang, Kevin Cai, Chaofeng Li, Anna Gao, Felen Fu, Hannah Bian, Bidyut Sen, Donghyun Kim

Electrical and Computer Engineering Faculty Research & Creative Works

In this study, the effects of using non-functional pads to optimize the performance of high-speed signal vias are investigated based on multiple reflection analysis. The non-functional pads on signal vias introduce more capacitive coupling and are possible to improve the response of the via structure if the original via has relatively larger impedance compared to the system reference impedance. The effectiveness of the non-functional pad optimization is validated through a numerical example, and the eye diagram of the via structure without and with non-functional pads are compared. The eye opening becomes 5.4 times larger after the via optimization using non-functional …


A Methodical Approach For Pcb Pdn Decoupling Minimizing Overdesign With Genetic Algorithm Optimization, F. De Paulis, Y. Ding, M. Cocchini, Chulsoon Hwang, S. Connor, M. Doyle, S. Scearce, W. D. Becker, Albert E. Ruehli, James L. Drewniak Jan 2022

A Methodical Approach For Pcb Pdn Decoupling Minimizing Overdesign With Genetic Algorithm Optimization, F. De Paulis, Y. Ding, M. Cocchini, Chulsoon Hwang, S. Connor, M. Doyle, S. Scearce, W. D. Becker, Albert E. Ruehli, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

An optimization routine is applied for the decoupling capacitor placement on Power Distribution Networks to identify the limit beyond which the placement of additional decaps is no longer effective, thus leading to wasting layout area and components, and to a cost increase. A specific test example from a real design is used together with the required target impedance and frequency band of interest for the PDN design. The effectiveness of the decap placement while selecting different layers of the stack-up, and while moving the upper limit of the PDN design band is analyzed. Such analysis leads to helpful insights based …


Identifying Sources Of Conducted Emissions By Measuring The Coherence Function, Xin Yan, Fuwei Ma, Wei Zhang, Kaustav Ghosh, Sameer Walunj, Philippe Sochoux, Victor Khilkevich Jan 2022

Identifying Sources Of Conducted Emissions By Measuring The Coherence Function, Xin Yan, Fuwei Ma, Wei Zhang, Kaustav Ghosh, Sameer Walunj, Philippe Sochoux, Victor Khilkevich

Electrical and Computer Engineering Faculty Research & Creative Works

Conducted emissions (CE) is one of the electromagnetic interference (EMI) issues that pose serious compliance problems for electronic devices. For a system with several sources, estimating the contribution of each source to conducted emission at different frequencies can be a challenge. In this article, a coherence function-based signal separation method is presented and validated on two commercial power supply units (PSU). The noise generated by the PSU and measured at the line impedance stabilization network (LISN) port contains two predominantly uncorrelated signals associated with the power factor correction (PFC) and H -bridge/rectifier circuits with unknown contributions at different frequencies. Two …


Physics-Based Modeling For Determining Transient Current Flow In Multi-Layer Pcb Pi Designs, Yifan Ding, Matthew S. Doyle, Samuel Connor, Dale Becker, James L. Drewniak Jan 2022

Physics-Based Modeling For Determining Transient Current Flow In Multi-Layer Pcb Pi Designs, Yifan Ding, Matthew S. Doyle, Samuel Connor, Dale Becker, James L. Drewniak

Electrical and Computer Engineering Faculty Research & Creative Works

A physics-based modeling methodology for determining the transient current flow path in multi-layer PI designs is given in this paper using a commercial board with a complicated structure as an example. Board structure analysis is done first to provide a physical basis of post-layout analytical and equivalent circuit modeling. A match of the PDN impedance between commercial tool simulation, post-layout analytical calculation, and the physics-based equivalent circuit modeling was achieved to support the model for the transient simulation. By analyzing the current response in all the vias, a clear representation of transient current flow across all via segments can be …


Two-Dimensional In-Plane Strain Fss-Based Sensor, Mahboobeh Mahmoodi, Kristen M. Donnell Jan 2022

Two-Dimensional In-Plane Strain Fss-Based Sensor, Mahboobeh Mahmoodi, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency selective surface (FSS) based sensors have found application as sensors in the last decade. In this paper, a new sensor design is proposed for two-dimensional in-plane strain sensing. The unit cell of the FSS-based sensor includes two slot dipoles, oriented normal to one another and each with different dimensions, to create two unique resonant frequencies when interrogated with an incident electric field normal to the direction of measured strain. In this way, 2D strain can be characterized concurrently and independently. The error due to strain orthogonal to the direction of interest, along with the error due to the presence …


A Meander Line-Based Frequency Selective Surface For Strain Sensing, Swathi Muthyala Ramesh, Kristen M. Donnell Jan 2022

A Meander Line-Based Frequency Selective Surface For Strain Sensing, Swathi Muthyala Ramesh, Kristen M. Donnell

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency selective surfaces (FSSs) are periodic arrays of conductive elements that have distinct reflection and transmission responses. In this work, an FSS sensor designed to operate in Ka-band to measure a wide range of uni-directional strain using a meander line-based unit cell is presented. Specifically, the proposed unit cell of the sensor consists of a convoluted meander line geometry designed on a thin dielectric substrate. Strain sensing is achieved by monitoring the change in the resonant frequency of the FSS when under strain that is parallel to an interrogating signal linearly polarized and aligned with the convoluted dimension of the …


De-Embedding For Coupled Three-Port Devices, Yuandong Guo, Bo Pu, Donghyun Kim, Jun Fan Jan 2022

De-Embedding For Coupled Three-Port Devices, Yuandong Guo, Bo Pu, Donghyun Kim, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In many applications, the device under test (DUT) is embedded into a test setup. Various de-embedding techniques have been proposed to expose the real electrical behaviors of a DUT, e.g., the traditional thru-reflect-line and short-open-load-thru algorithms, where the T-matrix and its inverse form are adopted in the mathematical process. In the fields of radiofrequency and electromagnetic compatibility, a DUT may have three coupled ports, and the symmetry in the associated S-matrix breaks down, because the numbers of entry and exist ports are not equal, which results in a non-square T-matrix based upon the definitions. Given that the inverse expression of …


Forecasting Nodal Price Difference Between Day-Ahead And Real-Time Electricity Markets Using Long-Short Term Memory And Sequence-To-Sequence Networks, Ronit Das, Rui Bo, Haotian Chen, Waqas Ur Rehman, Donald C. Wunsch Jan 2022

Forecasting Nodal Price Difference Between Day-Ahead And Real-Time Electricity Markets Using Long-Short Term Memory And Sequence-To-Sequence Networks, Ronit Das, Rui Bo, Haotian Chen, Waqas Ur Rehman, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

Price forecasting is at the center of decision making in electricity markets. Much research has been done in forecasting energy prices for a single market while little research has been reported on forecasting price difference between markets, which presents higher volatility and yet plays a critical role in applications such as virtual trading. To this end, this paper takes the first attempt at it and employs novel deep learning architecture with Bidirectional Long-Short Term Memory (LSTM) units and Sequence-to-Sequence (Seq2Seq) architecture to forecast nodal price difference between day-ahead and real-time markets. In addition to value prediction, these deep learning architectures …


Novel Data-Driven Spatial-Spectral Correlated Scheme For Dimensionality Reduction Of Hyperspectral Images, Yanming Zhang, Ping Yuan, Lijun Jiang, Hong Tat Ewe Jan 2022

Novel Data-Driven Spatial-Spectral Correlated Scheme For Dimensionality Reduction Of Hyperspectral Images, Yanming Zhang, Ping Yuan, Lijun Jiang, Hong Tat Ewe

Electrical and Computer Engineering Faculty Research & Creative Works

Hyperspectral imaging technology has been popularly applied in remote sensing because it collects echoed signals from across the electromagnetic (EM) spectrum and thereby contributes fruitfully spatial-spectral information. However, the processing or storage of high-data-volume hyperspectral images (HSIs), also viewed as snapshots varying with the EM spectrum, burdens the hardware resources, especially for the high spectral resolution and spatial resolution cases. To address this challenge, a novel unsupervised dimensionality reduction method based on the dynamic mode decomposition (DMD) algorithm is proposed to analyze hyperspectral data. This method decomposes the spatial-spectral HSIs in terms of spatial dynamic modes and corresponding spectral patterns. …


A Novel Data-Driven Modeling Method For The Spatial-Temporal Correlated Complex Sea Clutter, Yanming Zhang, Lijun Jiang, Hong Tat Ewe Jan 2022

A Novel Data-Driven Modeling Method For The Spatial-Temporal Correlated Complex Sea Clutter, Yanming Zhang, Lijun Jiang, Hong Tat Ewe

Electrical and Computer Engineering Faculty Research & Creative Works

The sea clutter, referred to as the time-varying radar backscatter from the ocean surface, plays a significant role in marine radar development. The ocean's complex hydrodynamics cause it to exhibit non-Gaussian and nonstationary characteristics, which brings challenges in the sea clutter modeling, especially for establishing its spatial-temporal correlated and coherent model. In this article, a data-driven method based on the Koopman mode decomposition (KMD) is proposed for modeling spatial-temporal correlated complex sea clutter. The method decomposes the coherent sea clutter dynamic behavior in terms of Koopman modes and corresponding temporal patterns. Then, these spatiotemporal patterns are used to construct the …


Single-Snapshot Localization For Near-Field Ris Model Using Atomic Norm Minimization, Omar Rinchi, Ahmed Elzanaty, Ahmad Alsharoa Jan 2022

Single-Snapshot Localization For Near-Field Ris Model Using Atomic Norm Minimization, Omar Rinchi, Ahmed Elzanaty, Ahmad Alsharoa

Electrical and Computer Engineering Faculty Research & Creative Works

Reconfigurable intelligent surfaces (RISs) are expected to play a significant role in the next generation of wireless cellular technology. This paper proposes an uplink localization scheme using a single-snapshot solution for user equipment (UE) that is located in the near-field of the RIS. We propose utilizing the atomic norm minimization method to achieve super-resolution localization accuracy. We formulate an optimization problem to estimate the UE location parameters (i.e., angles and distances) by minimizing the atomic norm. Then, we propose to exploit strong duality to solve the atomic norm problem using the dual problem and semidefinite programming (SDP). The RIS is …


Early Wildfire Detection Using Uavs Integrated With Air Quality And Lidar Sensors, Doaa Rjoub, Ahmad Alsharoa, Ala'eddin Masadeh Jan 2022

Early Wildfire Detection Using Uavs Integrated With Air Quality And Lidar Sensors, Doaa Rjoub, Ahmad Alsharoa, Ala'eddin Masadeh

Electrical and Computer Engineering Faculty Research & Creative Works

Every year, wildfires burn out countless hectares of lands, resulting in ecological, environmental, and economic damage. This paper presents an energy management system that consists of an unmanned aerial vehicle (UAV) equipped with air quality and light detection and ranging (LiDAR) sensors for monitoring forests and recognizing flames early. We develop a novel approach for autonomous patrolling system. This approach has the advantage of effectively detecting wildfire incidents, while optimizing the energy consumption of the UAV's battery to cover large areas. When a wildfire is detected, the UAV is able to transmit real-time data, such as sensor readings and LiDAR …


A High Step-Up Dc-Dc Converter Using A Three Winding Coupled Inductor For Photovoltaic To Grid Applications, Saeed Habibi, Ramin Rahimi, Mehdi Ferdowsi, Pourya Shamsi Jan 2022

A High Step-Up Dc-Dc Converter Using A Three Winding Coupled Inductor For Photovoltaic To Grid Applications, Saeed Habibi, Ramin Rahimi, Mehdi Ferdowsi, Pourya Shamsi

Electrical and Computer Engineering Faculty Research & Creative Works

A dual-switch high step-up DC-DC converter topology is proposed in this paper. The proposed topology uses two power switches, a three-winding coupled inductor (TWCI), and voltage multiplier cells to provide a high voltage gain. Furthermore, the voltage stresses on power semiconductor switches are low, resulting in lower switching and conduction losses. Moreover, the common electrical ground is preserved in this topology, making it a suitable candidate for photovoltaic (PV) to grid systems. The operating modes and steady state analysis of the proposed converter are presented, and a comparative study is carried out to demonstrate advantages of the proposed topology over …


Robust Modifications To Model Reference Adaptive Control For Reference Voltage Tracking In A Dual Active Bridge Dc-Dc Converter, Kartikeya J.P. Veeramraju, Alvaro Cardoza, Jagannathan Sarangapani, Jonathan W. Kimball Jan 2022

Robust Modifications To Model Reference Adaptive Control For Reference Voltage Tracking In A Dual Active Bridge Dc-Dc Converter, Kartikeya J.P. Veeramraju, Alvaro Cardoza, Jagannathan Sarangapani, Jonathan W. Kimball

Electrical and Computer Engineering Faculty Research & Creative Works

Model Reference Adaptive Control (MRAC) is useful for achieving a desired dynamic response with no prior knowledge of system parameters. Traditional MRAC is sensitive to noise in the state variables, leading to adaptation parametric drift. The drift in parameters, if left unchecked, leads to loss of closed loop stability. In power electronic systems, the ripple in the output voltage serves as a bounded noise, which leads to MRAC instability. This drift phenomenon is observed through the simulation and hardware experimentation of a Dual Active Bridge (DAB) converter and mitigated using deadzone modification and σ modification approaches. These two methods are …


Hamiltonian-Driven Adaptive Dynamic Programming With Efficient Experience Replay, Yongliang Yang, Yongping Pan, Cheng Zhong Xu, Donald C. Wunsch Jan 2022

Hamiltonian-Driven Adaptive Dynamic Programming With Efficient Experience Replay, Yongliang Yang, Yongping Pan, Cheng Zhong Xu, Donald C. Wunsch

Electrical and Computer Engineering Faculty Research & Creative Works

This article presents a novel efficient experience-replay-based adaptive dynamic programming (ADP) for the optimal control problem of a class of nonlinear dynamical systems within the Hamiltonian-driven framework. The quasi-Hamiltonian is presented for the policy evaluation problem with an admissible policy. With the quasi-Hamiltonian, a novel composite critic learning mechanism is developed to combine the instantaneous data with the historical data. In addition, the pseudo-Hamiltonian is defined to deal with the performance optimization problem. Based on the pseudo-Hamiltonian, the conventional Hamilton–Jacobi–Bellman (HJB) equation can be represented in a filtered form, which can be implemented online. Theoretical analysis is investigated in terms …


Clock Duty Cycle Tuning For Desense Mitigation In Modulation -Involved Cases, Shengxuan Xia, Jun Fan, Chulsoon Hwang Jan 2022

Clock Duty Cycle Tuning For Desense Mitigation In Modulation -Involved Cases, Shengxuan Xia, Jun Fan, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

Nowadays consumers' electronic devices are highly integrated, and modules and integrated circuits (ICs) are usually placed close to each other due to the compact size. The modules and ICs may interfere with the radio frequency (RF) antennas and cause desense issues. In recent years, desense caused by direct coupling from the noise sources to the victim RF antennas has been well studied. However, more complicated mechanisms such as modulations between transmitting signals and low-frequency clock or data signals can also result in desense problems, especially in frequency divide duplex (FDD) applications. Typical solutions to desense problems will focus on suppressing …


Chimeranet: U-Net For Hair Detection In Dermoscopic Skin Lesion Images, Norsang Lama, Reda Kasmi, Jason R. Hagerty, R. Joe Stanley, Reagan Harris Young, Jessica Miinch, Januka Nepal, Anand Nambisan, William V. Stoecker Jan 2022

Chimeranet: U-Net For Hair Detection In Dermoscopic Skin Lesion Images, Norsang Lama, Reda Kasmi, Jason R. Hagerty, R. Joe Stanley, Reagan Harris Young, Jessica Miinch, Januka Nepal, Anand Nambisan, William V. Stoecker

Electrical and Computer Engineering Faculty Research & Creative Works

Hair and ruler mark structures in dermoscopic images are an obstacle preventing accurate image segmentation and detection of critical network features. Recognition and removal of hairs from images can be challenging, especially for hairs that are thin, overlapping, faded, or of similar color as skin or overlaid on a textured lesion. This paper proposes a novel deep learning (DL) technique to detect hair and ruler marks in skin lesion images. Our proposed ChimeraNet is an encoder-decoder architecture that employs pretrained EfficientNet in the encoder and squeeze-and-excitation residual (SERes) structures in the decoder. We applied this approach at multiple image sizes …


Dielectric Loss Tangent Extraction Using Two Single-Ended Striplines Of Different Width, Jiangshuai Li, Yuanzhuo Liu, Liang Liu, Shengxuan Xia, Scott Hinaga, Victor Khilkevich Jan 2022

Dielectric Loss Tangent Extraction Using Two Single-Ended Striplines Of Different Width, Jiangshuai Li, Yuanzhuo Liu, Liang Liu, Shengxuan Xia, Scott Hinaga, Victor Khilkevich

Electrical and Computer Engineering Faculty Research & Creative Works

Frequency-dependent electrical properties of dielectric materials are one of the most important factors for high-speed signal integrity design. Recently a method of accurately measuring the dielectric loss tangent ($\tan \delta$) of differential lines was proposed. By taking into account the ratio between the differential and common mode per-unit-length resistances the surface roughness contribution to the total loss is eliminated and dielectric parameters can be determined. In this article a similar method is applied to a combination of two single-ended lines. To evaluate the accuracy of the extraction, the impact of the de-embedding errors was investigated, which allows to optimize the …


A Fast Cascading Method For Predicting The Coupling From External Plane Waves To Pcbs, Shengxuan Xia, James Hunter, Aaron Harmon, Mohamed Z.M. Hamdalla, Ahmed M. Hassan, Chulsoon Hwang, Victor Khilkevich, Daryl G. Beetner Jan 2022

A Fast Cascading Method For Predicting The Coupling From External Plane Waves To Pcbs, Shengxuan Xia, James Hunter, Aaron Harmon, Mohamed Z.M. Hamdalla, Ahmed M. Hassan, Chulsoon Hwang, Victor Khilkevich, Daryl G. Beetner

Electrical and Computer Engineering Faculty Research & Creative Works

The radio frequency (RF) coupling to electronic devices impacts their EMC performance. The functionalities of a working electronic device may be disrupted when the electromagnetic (EM) coupling reaches a certain level. Studies of the EM coupling to printed circuit boards (PCBs) are therefore essential for RF susceptibility and EMC purposes. For decades, researchers focused on the analytical modeling of EM coupling to transmission lines. However, when it comes to more realistic PCBs the analysis usually still relies heavily on full-wave simulations because of the complexity of the structures and the lack of analytical solutions. Using a traditional full-wave modeling approach, …


A Practical Simulation Flow For Singing Capacitor Based Acoustic Noise Analysis, Xin Yan, Songping Wu, Mingfeng Xue, Chi Kin Benjamin Leung, Daryl G. Beetner, Jianmin Zhang Jan 2022

A Practical Simulation Flow For Singing Capacitor Based Acoustic Noise Analysis, Xin Yan, Songping Wu, Mingfeng Xue, Chi Kin Benjamin Leung, Daryl G. Beetner, Jianmin Zhang

Electrical and Computer Engineering Faculty Research & Creative Works

Multilayer ceramic capacitors (MLCCs) are widely used in modern electronics. Due to the piezoelectric effect of the ceramic material, however, MLCCs subjected to electrical noise may vibrate and generate acoustic noise, as 'singing'. Acoustic noise can be annoying for users, especially within mobile devices, so it becomes important to perform acoustic noise analysis before a product is released. In this paper, a practical simulation flow for singing capacitor based acoustic noise is presented. The simulation flow and analysis method are developed on Ansys Sherlock and Mechanical. In Ansys Sherlock, local library and Approved Vendor List (AVL) files were used to …