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Articles 57391 - 57420 of 197987

Full-Text Articles in Engineering

A Nonlinear Distortion Removal Based On Deep Neural Network For Underwater Acoustic Ofdm Communication With The Mitigation Of Peak To Average Power Ratio, Xuefei Ma, Waleed Raza, Zhiqiang Wu, Muhammad Bilal, Ziqi Zhou, Amir Ali Jul 2020

A Nonlinear Distortion Removal Based On Deep Neural Network For Underwater Acoustic Ofdm Communication With The Mitigation Of Peak To Average Power Ratio, Xuefei Ma, Waleed Raza, Zhiqiang Wu, Muhammad Bilal, Ziqi Zhou, Amir Ali

Electrical Engineering Faculty Publications

Machine learning and deep learning algorithms have proved to be a powerful tool for developing data-driven signal processing algorithms for challenging engineering problems. This paper studies the modern machine learning algorithm for modeling nonlinear devices like power amplifiers (PAs) for underwater acoustic (UWA) orthogonal frequency divisional multiplexing (OFDM) communication. The OFDM system has a high peak to average power ratio (PAPR) in the time domain because the subcarriers are added coherently via inverse fast Fourier transform (IFFT). This causes a higher bit error rate (BER) and degrades the performance of the PAs; hence, it reduces the power efficiency. For long-range …

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Models For Data Analysis In Accelerated Reliability Growth, Cesar Alexander Ruiz Torres Jul 2020

Models For Data Analysis In Accelerated Reliability Growth, Cesar Alexander Ruiz Torres

Graduate Theses and Dissertations

This work develops new methodologies for analyzing accelerated testing data in the context of a reliability growth program for a complex multi-component system. Each component has multiple failure modes and the growth program consists of multiple test-fix stages with corrective actions applied at the end of each stage. The first group of methods considers time-to-failure data and test covariates for predicting the final reliability of the system. The time-to-failure of each failure mode is assumed to follow a Weibull distribution with rate parameter proportional to an acceleration factor. Acceleration factors are specific to each failure mode and test covariates. We …

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Machine Tool Communication (Mtcomm) Method And Its Applications In A Cyber-Physical Manufacturing Cloud, S M Nahian Al Sunny Jul 2020

Machine Tool Communication (Mtcomm) Method And Its Applications In A Cyber-Physical Manufacturing Cloud, S M Nahian Al Sunny

Graduate Theses and Dissertations

The integration of cyber-physical systems and cloud manufacturing has the potential to revolutionize existing manufacturing systems by enabling better accessibility, agility, and efficiency. To achieve this, it is necessary to establish a communication method of manufacturing services over the Internet to access and manage physical machines from cloud applications. Most of the existing industrial automation protocols utilize Ethernet based Local Area Network (LAN) and are not designed specifically for Internet enabled data transmission. Recently MTConnect has been gaining popularity as a standard for monitoring status of machine tools through RESTful web services and an XML based messaging structure, but it …

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Design Of Control System With Feedback Loop For A Pulsatile Pump, Ian Scott Sanders Jul 2020

Design Of Control System With Feedback Loop For A Pulsatile Pump, Ian Scott Sanders

Graduate Theses and Dissertations

This paper describes the design and implementation of a closed-loop proportional, integral, differential (PID) control system for a custom in-house pulsatile pump apparatus for the University of Arkansas Biomedical Department. The control system is designed to control a MOONS’ PL34HD0L8500 hybrid stepper motor using a dual H-bridge motor driver network with four pulse-width modulated (PWM) inputs to drive a pulsatile pump apparatus at motor stepping frequencies up to 2kHz. The speed of the motor is controlled from a pressure profile transmitted from an external source over RS-232 communication that specifies the motor speed, number of datapoints, and an array of …

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Development Of A Reference Design For A Cyber-Physical System, Nicholas Paul Blair Jul 2020

Development Of A Reference Design For A Cyber-Physical System, Nicholas Paul Blair

Graduate Theses and Dissertations

The purpose of this thesis is to develop a reference design to assist in the selection of security practices in power electronics design. A prototype will be developed from this reference design for evaluation. This evaluation will include a brief cost/benefit analysis to gauge the efficacy of implementing each layer of security throughout the power electronics design process. This thesis will also describe the obstacles and effectiveness of integrating a Trusted Platform Module (TPM) into a cyber-hardened grid-connected device. The TPM device is a secured crypto processor that assists in generating, storing, and restricting the use of cryptographic keys. The …

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What Difference Does A Catalyst Make?, Tammy Guthrie, Mike Jackson, Holly Haney Jul 2020

What Difference Does A Catalyst Make?, Tammy Guthrie, Mike Jackson, Holly Haney

High School Lesson Plans

Students will use different catalysts for the decomposition of Hydrogen Peroxide, to determine if different catalysts affect the energy that is generated during the reaction.

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Optimization Of Railroad Bearing Health Monitoring System For Wireless Utilization, Jonas Cuanang, Constantine Tarawneh, Martin Amaro Jr., Jennifer Lima, Heinrich D. Foltz Jul 2020

Optimization Of Railroad Bearing Health Monitoring System For Wireless Utilization, Jonas Cuanang, Constantine Tarawneh, Martin Amaro Jr., Jennifer Lima, Heinrich D. Foltz

Mechanical Engineering Faculty Publications

In the railroad industry, systematic health inspections of freight railcar bearings are required. Bearings are subjected to high loads and run at high speeds, so over time the bearings may develop a defect that can potentially cause a derailment if left in service operation. Current bearing condition monitoring systems include Hot-Box Detectors (HBDs) and Trackside Acoustic Detection Systems (TADS™). The commonly used HBDs use non-contact infrared sensors to detect abnormal temperatures of bearings as they pass over the detector. Bearing temperatures that are about 94°C above ambient conditions will trigger an alarm indicating that the bearing must be removed from …

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Processing-Structure-Property Relationships Of Biopolyester/Zinc Oxide Fibrous Scaffolds Engineered By Centrifugal Spinning, Victoria Padilla-Gainza, Heriberto Rodríguez-Tobías, Graciela Morales, Antonio Ledezma-Pérez, Carmen Alvarado-Canché, Cristobal Rodriguez, Robert Gilkerson, Karen Lozano Jul 2020

Processing-Structure-Property Relationships Of Biopolyester/Zinc Oxide Fibrous Scaffolds Engineered By Centrifugal Spinning, Victoria Padilla-Gainza, Heriberto Rodríguez-Tobías, Graciela Morales, Antonio Ledezma-Pérez, Carmen Alvarado-Canché, Cristobal Rodriguez, Robert Gilkerson, Karen Lozano

Mechanical Engineering Faculty Publications

This study addresses the processing of nonwoven fibrous materials obtained by centrifugal spinning method, namely Forcespinning; a high yield and low production cost technique little explored in this field. Poly(D, L-lactic acid) (PDLLA) and poly(3-hydroxybutyrate) (PHB) were used as matrices and reinforced with zinc oxide nanoparticles (n-ZnO). The morphology, mechanical, and thermal performance of the developed composites were analyzed as well as the antibacterial effect of n-ZnO. Fibrous materials with n-ZnO concentrations of 1, 3, and 5 wt. % for PDLLA and 1 and 3 wt. % for PHB were evaluated. The results showed that the incorporation of n-ZnO produces …

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A Design Of Taper-Like Etched Multicore Fiber Refractive Index-Insensitive A Temperature Highly Sensitive Mach-Zehnder Interferometer, Farhan Mumtaz, Pu Cheng, Chi Li, Shu Cheng, Cheng Du, Minghong Yang, Yutang Dai, Wenbin Hu Jul 2020

A Design Of Taper-Like Etched Multicore Fiber Refractive Index-Insensitive A Temperature Highly Sensitive Mach-Zehnder Interferometer, Farhan Mumtaz, Pu Cheng, Chi Li, Shu Cheng, Cheng Du, Minghong Yang, Yutang Dai, Wenbin Hu

Electrical and Computer Engineering Faculty Research & Creative Works

We propose and demonstrate Mach-Zehnder interferometer (MZI), which is the refractive index (RI) insensitive and temperature highly sensitive based on etched multi-core fiber (MCF) structure. The MCF and Fiber Bragg Grating (FBG) are used as hybrid sensing elements. The fabrication of the interferometer is provided a new taper-like structure by etching the MCF to further expose the side cores to the surroundings. The interferometer has produced a sensitivity of 103.2pm/°C within the ambient temperature up-to 70°C. Moreover, the superior temperature sensitivity is 89.19pm/°C, 66.64pm/°C, 56.42pm/°C in the range of 24°C to 130°C, and RI-insensitive in the range of 1.34 to …

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Multi-Homotopy Class Optimal Path Planning For Manipulation With One Degree Of Redundancy, Jacob J. Rice, Joseph M. Schimmels Jul 2020

Multi-Homotopy Class Optimal Path Planning For Manipulation With One Degree Of Redundancy, Jacob J. Rice, Joseph M. Schimmels

Mechanical Engineering Faculty Research and Publications

Redundant manipulators have an infinitely large set of joint paths that yield a desired end-effector path in the task space. A unique joint path can be obtained by minimizing a global cost function. Prior optimal control methods minimize a global cost function to find a local minimum within a homotopy class. Many possible locally optimal joint paths are in different homotopy classes. This paper presents an algorithm that effectively searches the solution space and finds many locally optimal paths in all relevant homotopy classes. The path with the lowest cost is very likely the globally optimal path. The algorithm is …

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Adaptive Interference Mitigation Using Frequency-Selective Limiters Over Gps Band For Automotive Applications, Mahima Shukla, Marina Y. Koledintseva, Michael Geiler, Scott Gillette, Michael Hunnewell, Anton L. Geiler Jul 2020

Adaptive Interference Mitigation Using Frequency-Selective Limiters Over Gps Band For Automotive Applications, Mahima Shukla, Marina Y. Koledintseva, Michael Geiler, Scott Gillette, Michael Hunnewell, Anton L. Geiler

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, we address the challenges associated with the necessity to protect Global Positioning system (GPS) receivers from various types of electromagnetic interference (EMI) generated by internal or external sources. We have developed a compact, lightweight, and passive frequency selective limiter (FSL) technology that automatically and adaptively protects vulnerable input circuits of a GPS receiver from unwanted emissions and prevents a GPS receiver from going into saturation. This technology is based on using magnetostatic surface waves in a magnetically biased ferrite film. The nonlinear processes in ferrite films enable discrimination of signals based on their power levels. In these …

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Improved Classification Of Medical Data Using Meta-Best Feature Selection, Matthew Chaplin, Jacob Grubb, Thomas Clifford, Justin Bruce, Tayo Obafemi-Ajayi, John Matta Jul 2020

Improved Classification Of Medical Data Using Meta-Best Feature Selection, Matthew Chaplin, Jacob Grubb, Thomas Clifford, Justin Bruce, Tayo Obafemi-Ajayi, John Matta

Electrical and Computer Engineering Faculty Research & Creative Works

Feature selection provides a useful method for reducing the size of large data sets while maintaining integrity, thereby improving the accuracy of neural networks and other classifiers. However, running multiple feature selection models and their accompanying classifiers can make interpreting results difficult. To this end, we present a data-driven methodology called Meta-Best that not only returns a single feature set related to a classification target, but also returns an optimal size and ranks the features by importance within the set. This proposed methodology is tested on six distinct targets from the well-known REGARDS dataset: Deceased, Self-Reported Diabetes, Light Alcohol Abuse …

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Improving Mode Ii Fracture Toughness Of Secondary Bonded Joints Using Laser Patterning Of Adherends, A. Wagih, R. Tao, A. Yudhanto, G. Lubineau Jul 2020

Improving Mode Ii Fracture Toughness Of Secondary Bonded Joints Using Laser Patterning Of Adherends, A. Wagih, R. Tao, A. Yudhanto, G. Lubineau

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We improve mode II fracture toughness of secondary bonded joints based on the laser treatment of adherend surfaces. We applied CO2 Laser treatment to adherend surface alternatively with low and high energy, resulting in a repeated pattern of rough and smooth surfaces. We used ENF test to characterize mode II fracture toughness, GII, of the bonded CFRP substrates. The results demonstrated that our proposed pattern arrested the crack propagation and triggered new damage mechanisms, such as adhesive cracking, adhesive failure and crack migration to the other interface. These additional mechanisms, some of them were non-local in nature, resulted in …

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How The Spatial Correlation In Adhesion Properties Influences The Performance Of Secondary Bonding Of Laminated Composites, Xiaole Li, Ran Tao, Arief Yudhanto, Gilles Lubineau Jul 2020

How The Spatial Correlation In Adhesion Properties Influences The Performance Of Secondary Bonding Of Laminated Composites, Xiaole Li, Ran Tao, Arief Yudhanto, Gilles Lubineau

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Spatial heterogeneity of adhesion properties is known to result in bridging during debonding of secondary bonded composite joints. The ligaments that bridge both substrates have crack-arrest features and thus significantly enhance the fracture resistance of joints. We have investigated the effect of randomly distributed adhesion properties between the adhesive layer and each composite substrate in previous works; however, the spatial correlation of adhesion heterogeneity within or between the substrates and how it effects the failure of secondary bonded composites is still poorly understood. In this current work, we assume that the spatial heterogeneity of adhesion follows a log-normal distribution. The …

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An Algorithm For The Evolutionary-Fuzzy Generation Of On-Line Signature Hybrid Descriptors, Marcin Zalasinski, Krzysztof Cpalka, Lukasz Laskowski, Donald C. Wunsch, Krzystof Przybyszewski Jul 2020

An Algorithm For The Evolutionary-Fuzzy Generation Of On-Line Signature Hybrid Descriptors, Marcin Zalasinski, Krzysztof Cpalka, Lukasz Laskowski, Donald C. Wunsch, Krzystof Przybyszewski

Electrical and Computer Engineering Faculty Research & Creative Works

In biometrics, methods which are able to precisely adapt to the biometric features of users are much sought after. They use various methods of artificial intelligence, in particular methods from the group of soft computing. In this paper, we focus on on-line signature verification. Such signatures are complex objects described not only by the shape but also by the dynamics of the signing process. In standard devices used for signature acquisition (with an LCD touch screen) this dynamics may include pen velocity, but sometimes other types of signals are also available, e.g. pen pressure on the screen surface (e.g. in …

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Effects Of Zirconia Doping On Additively Manufactured Alumina Ceramics By Laser Direct Deposition, John M. Pappas, Aditya R. Thakur, Xiangyang Dong Jul 2020

Effects Of Zirconia Doping On Additively Manufactured Alumina Ceramics By Laser Direct Deposition, John M. Pappas, Aditya R. Thakur, Xiangyang Dong

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The ability to additively manufacture functional alumina ceramics has the potential to lower manufacturing costs and development time for complex components. In this study, the doping effects of zirconia on laser direct deposited alumina ceramics were investigated. The microstructure of the printed samples was analyzed in terms of grain size and composition distribution. The addition of zirconia was found to accumulate along alumina grain boundaries and resulted in significant grain refinement. The zirconia doping largely reduced crack formation during processing compared to that of pure alumina samples. In the case of 10 wt% zirconia, cracking during deposition was nearly completely …

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Optimal Control Of Linear Continuous-Time Systems In The Presence Of State And Input Delays With Application To A Chemical Reactor, Rohollah Moghadam, Sarangapani Jagannathan Jul 2020

Optimal Control Of Linear Continuous-Time Systems In The Presence Of State And Input Delays With Application To A Chemical Reactor, Rohollah Moghadam, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, the optimal regulation of linear continuous-time systems with state and input delays is introduced by utilizing a quadratic cost function and state feedback. The Lyapunov-Krakovskii functional incorporating state and input delays is defined as a value function. Next, the Bellman type equation is formulated, and a delay Algebraic Riccati equation (DARE) over infinite time horizon is derived. By using the stationarity condition for the Bellman type equation, the optimal control input is obtained. It is demonstrated that the proposed optimal control input makes the closed-loop system asymptotically stable. Finally, simulation results confirm the theoretical claims by applying …

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Measurement Of The Amplitude And Phase Response Of Harmonic Products In Protection Diodes, Marcelo B. Perotoni, Omid Hoseini Izadi, David Pommerenke Jul 2020

Measurement Of The Amplitude And Phase Response Of Harmonic Products In Protection Diodes, Marcelo B. Perotoni, Omid Hoseini Izadi, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

This paper provides initial data from a measurement setup that captures not only the magnitude of unwanted harmonic signals created by TVS diodes but also measures their phase. Initial SPICE simulations are used for qualitative comparison. Goal is to use the phase information to gain in-sight into the mechanisms that create harmonics, not only for Transient Voltage Supressor diodes, but also for imperfect metallic contacts.

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Distributed Adaptive State Estimation And Tracking Scheme For Nonlinear Systems Using Active Passive Sensor Networks, Akhilesh Raj, S. Jagannathan, Tansel Yucelen Jul 2020

Distributed Adaptive State Estimation And Tracking Scheme For Nonlinear Systems Using Active Passive Sensor Networks, Akhilesh Raj, S. Jagannathan, Tansel Yucelen

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposes a novel adaptive neural network (NN) based distributed state estimation scheme for a heterogeneous sensor network (HSN), to estimate the state vector of an unknown nonlinear process/target by using sensed output when the target input remains unknown. The active nodes in the HSN can sense the target output based on the detection range. By using a connected graph, the active nodes will communicate their estimated state vector from their adaptive NN observer to other passive nodes in the neighborhood that cannot sense the target, so that they can estimate the target state vector. Next, a subset of …

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Complex Permittivity Extraction From Synthetic Aperture Radar Images, Yuan Gao, Mohammad Tayeb Al Qaseer, Reza Zoughi Jul 2020

Complex Permittivity Extraction From Synthetic Aperture Radar Images, Yuan Gao, Mohammad Tayeb Al Qaseer, Reza Zoughi

Electrical and Computer Engineering Faculty Research & Creative Works

Microwave and millimeter wave synthetic aperture radar (SAR) imaging techniques are commonly used to generate high-resolution qualitative images showing the reflectivity (or complex permittivity) contrast in a sample-under-test (SUT). These techniques have been successfully applied for many diverse applications. However, these images lack quantitative information about the SUT, namely, its complex permittivity distribution. In this article, a novel method to extract the spatial distribution of complex permittivity from SAR images is proposed. The principle of the proposed method is outlined, then verified by a series of electromagnetic simulations, demonstrating that the proposed method can accurately extract the complex permittivity. Additionally, …

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Noise Coupling Mechanism Analysis And Mitigation Method For Receiver Sensitivity Improvement In An Optical Qsfp Transceiver Module, Yuandong Guo, Shuai Jin, Xinglin Sun, Jun Fan Jul 2020

Noise Coupling Mechanism Analysis And Mitigation Method For Receiver Sensitivity Improvement In An Optical Qsfp Transceiver Module, Yuandong Guo, Shuai Jin, Xinglin Sun, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

The increasingly growth of the traffic in data centers demands for high-speed data transition and high bandwidth density. Optical communication is a promising way for the propagation of high-speed signals with less distortions. The quad small form-factor pluggable (QSFP) transceiver module is an essential component converting an electrical signal into an optical signal for point-to-point data transition. Considerable attentions have been paid to the signal integrity (SI) optimization for the optical QSFP transceiver modules with different data rates, where the receiver sensitivity is generally considered to be critical. In this paper, the receiver sensitivity problem of a typical QSFP transceiver …

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Electric Parameter Tuning Of Wireless Power Transfer Coil For Charging Interoperability Of Electric Vehicles, Dongwook Kim, Seungyoung Ahn, Qiusen He, Anfeng Huang, Jun Fan, Hongseok Kim Jul 2020

Electric Parameter Tuning Of Wireless Power Transfer Coil For Charging Interoperability Of Electric Vehicles, Dongwook Kim, Seungyoung Ahn, Qiusen He, Anfeng Huang, Jun Fan, Hongseok Kim

Electrical and Computer Engineering Faculty Research & Creative Works

The SAE J2954 recommended practice (RP) contains the power transfer frequency, electric values, and test procedure for the electric vehicle (EV) wireless power transfer (WPT). In particular, this document expresses the inductance range of the powering coil, the power receiving coil and the coupling coefficient (k) and the impedance values. It is very important that adhering the electrical parameters in the standard considering that the wireless charging system's compatibility. However, once the coil is processed, it is not easy to adjust the inductance of each powering coil, power receiving coil as well as the coupling coefficient of between transmitting coil …

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Generic Modeling Of Differential Striplines Using Machine Learning Based Regression Analysis, Srinath Penugonda, Shaohui Yong, Anna Gao, Kevin Cai, Bidyut Sen, Jun Fan Jul 2020

Generic Modeling Of Differential Striplines Using Machine Learning Based Regression Analysis, Srinath Penugonda, Shaohui Yong, Anna Gao, Kevin Cai, Bidyut Sen, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, a generic model for a differential strip line is created using machine learning (ML) based regression analysis. A recursive approach of creating various inputs is adapted instead of traditional design of experiments (DoE) approach. This leads to reduction of number of simulations as well as control the data points required for performing simulations. The generic model is developed using 48 simulations. It is comparable to the linear regression model, which is obtained using 1152 simulations. Additionally, a tabular W-element model of a differential strip line is used to take into consideration the frequency-dependent dielectric loss. In order …

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An Enhanced Deep Reinforcement Learning Algorithm For Decoupling Capacitor Selection In Power Distribution Network Design, Ling Zhang, Wenchang Huang, Jack Juang, Hank Lin, Bin Chyi Tseng, Chulsoon Hwang Jul 2020

An Enhanced Deep Reinforcement Learning Algorithm For Decoupling Capacitor Selection In Power Distribution Network Design, Ling Zhang, Wenchang Huang, Jack Juang, Hank Lin, Bin Chyi Tseng, Chulsoon Hwang

Electrical and Computer Engineering Faculty Research & Creative Works

The selection of decoupling capacitors (decap) is a critical but tedious process in power distribution network (PDN) design. In this paper, an improved decap-selection algorithm based on deep reinforcement learning (DRL), which seeks the minimum number of decaps through a self-exploration training to satisfy a given target impedance, is presented. Compared with the previous relevant work: the calculation speed of PDN impedance is significantly increased by adopting an impedance matrix reduction method; also, the enhanced algorithm performs a better convergence by utilizing the techniques of double Q-learning and prioritized experience replay; furthermore, a well-designed reward is proposed to facilitate long-term …

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Predicting The Conducted Emission Of A Crm Pfc Below 1mhz By Transient Modeling, Hongseok Kim, Jiayi He, Chunyu Wu, Nicholas Erickson, Sangho Cho, Dohyung Kim, Yeong Hur, Jun Fan Jul 2020

Predicting The Conducted Emission Of A Crm Pfc Below 1mhz By Transient Modeling, Hongseok Kim, Jiayi He, Chunyu Wu, Nicholas Erickson, Sangho Cho, Dohyung Kim, Yeong Hur, Jun Fan

Electrical and Computer Engineering Faculty Research & Creative Works

Power Factor Corrections (PFC) are widely used in ac to dc power supplies. Modeling the PFC circuits and predicting the conducted emission (CE) are important in power supply designs. This paper introduces a transient model of a critical conduction mode (CRM) power factor correction. The control circuit of the PFC is built to achieve a CRM working condition with a constant on-time switching. The simulated time domain noise waveform is converted to the conducted EMI in frequency domain via short-time fast Fourier transform (STFFT). The simulated conducted EMI is compared to measured results below 1MHz.

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Investigation And Mitigation Of Radio Frequency Interference Caused By Weak Grounding Of Usb Type-C Receptacle Connector, Anfeng Huang, Xin Yan, Jingdong Sun, Qiaolei Huang, Jun Fan, Songping Wu, Dave Zhang, Huan Liao, Shuai Jin, Zhiping Yang Jul 2020

Investigation And Mitigation Of Radio Frequency Interference Caused By Weak Grounding Of Usb Type-C Receptacle Connector, Anfeng Huang, Xin Yan, Jingdong Sun, Qiaolei Huang, Jun Fan, Songping Wu, Dave Zhang, Huan Liao, Shuai Jin, Zhiping Yang

Electrical and Computer Engineering Faculty Research & Creative Works

In modern mobile electronic systems, USB connector has been identified as one of the dominant noise sources for desense issues. In this paper, the noise coupled to the Wi-Fi antenna from a USB connector is investigated. With the assistance of full-wave simulations, the root cause of desense noise is identified as the non-ideal electrical connection between the metal chassis and the USB receptacle shell where it is installed. The proposed radiation mechanism is validated through measurements of a real tablet device, and 15 dB noise level reduction is observed with a better grounding structure.

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Enhanced Deep Learning Approach Based On The Deep Convolutional Encoder-Decoder Architecture For Electromagnetic Inverse Scattering Problems, He Ming Yao, Lijun Jiang, Wei E.I. Sha Jul 2020

Enhanced Deep Learning Approach Based On The Deep Convolutional Encoder-Decoder Architecture For Electromagnetic Inverse Scattering Problems, He Ming Yao, Lijun Jiang, Wei E.I. Sha

Electrical and Computer Engineering Faculty Research & Creative Works

This letter proposes a novel deep learning (DL) approach to resolve the electromagnetic inverse scattering (EMIS) problems. The conventional approaches of resolving EMIS problems encounter assorted difficulties, such as high contrast, high computational cost, inevitable intrinsic nonlinearity, and strong ill-posedness. To surmount these difficulties, a novel DL approach is proposed based on a novel complex-valued deep fully convolutional neural network structure. The proposed complex-valued deep learning model for solving EMIS problems composes of an encoder network and its corresponding decoder network, followed by a final pixel-wise regression layer. The complex-valued encoder network extracts feature fragments from received scattered field data, …

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Earthquake Magnitude And Grid-Based Location Prediction Using Backpropagation Neural Network, Bagus Priambodo, Wayan Firdaus Mahmudy, Muh Arif Rahman Jul 2020

Earthquake Magnitude And Grid-Based Location Prediction Using Backpropagation Neural Network, Bagus Priambodo, Wayan Firdaus Mahmudy, Muh Arif Rahman

Knowledge Engineering and Data Science

Earthquakes, a type of inevitable natural disaster, is responsible for the highest average death toll per year compared to other types of a natural disaster. Even though it is inevitable, but it can be anticipated to minimize damage and casualties, such as predicting the earthquake‘s magnitude using a neural network. In this study, a backpropagation algorithm is used to train the multilayer neural network to weekly predict the average magnitude of earthquakes in grid-based locations in Indonesia. Based on the findings in this research, the neural network is able to predict the magnitude of earthquakes in grid-based locations across Indonesia …

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How Does Robotic Surgery Influence Communication, Leadership, And Team Outcomes? A Multimethod Examination., Jordan E. Rogers Jul 2020

How Does Robotic Surgery Influence Communication, Leadership, And Team Outcomes? A Multimethod Examination., Jordan E. Rogers

Doctoral Dissertations and Master's Theses

The practice of delivering surgical care has evolved to be less invasive to the patients undergoing surgery. Minimally-invasive surgery can be practiced through traditional laparoscopic methods as well as with robotic technology that displaces the surgeon from the operating table. Robotic surgery has been cited to be safer and more effective than traditional laparoscopic surgery; however, little research has endeavored to investigate the role of surgical modality upon aspects of teamwork. This dissertation contributes to the human factors and teamwork literature by evaluating how surgical modality may influence communication, shared leadership, and team outcomes. Multiple methods were employed to study …

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Optimization Of Spacecraft Formations About Lagrange Points For The Next Generation Space Weather Prediction Mission, Roberto Cuéllar Rangel Jul 2020

Optimization Of Spacecraft Formations About Lagrange Points For The Next Generation Space Weather Prediction Mission, Roberto Cuéllar Rangel

Doctoral Dissertations and Master's Theses

This thesis’s work serves as proof of concept for the Next Generation Space Weather Prediction Mission, a multi-spacecraft mission at various libration points whose objective is to forecast Space Weather hazards with a 12day warning time. This thesis deals with the design and control of orbits of spacecraft formations at different libration points. The systems studied are SunEarth, SunVenus, SunMercury, and SunMars. The orbit design and formation keeping control of the spacecraft are solved simultaneously using an optimization software called DIDO. Initial conditions are obtained through two different strategies. The first one, by placing the spacecraft in a tetrahedral formation …

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