Engineering Commons^™

Automatic Sparse Esm Scan Using Gaussian Process Regression, Jiangshuai Li

Masters Theses

“Emission source microscopy (ESM) technique can be utilized for localization of electromagnetic interference sources in complex and large systems. In this work a Gaussian process regression (GPR) method is applied in real-time to select sampling points for the sparse ESM imaging using a motorized scanner. The Gaussian process regression is used to estimate the complex amplitude of the scanned field and its uncertainty allowing to select the most relevant areas for scanning. Compared with the randomly selected samples the proposed method allows to reduce the number of samples needed to achieve a certain dynamic range of the image, reducing the …

Optimization And Modeling Of Esd Protection Devices, Li Shen

Masters Theses

“Transient voltage suppressors (TVS) are used to protect ICs (integrated circuits) against overvoltage, ESD (Electrostatic Discharge), inductive load switching, and even lightning strikes. In this research, a transient behavior model framework for ESD protection devices is used for modelling four different types of TVS (non-snapback, snapback, spark gap like device and varistor). The System-Efficient ESD Design (SEED) methodology is utilized to strengthen the trust in the model framework by efficient simulation of ESD interaction of the off-chip ESD protection devices with the IC ESD protection device and associated measurement data.

Improvements in the TVS transient response, accounting for conductivity modulation, …

Analysis Of Electromagnetic Interference Problems Causedbyhigh-Speed Multiplayer Boards With Split Referenceplane, Xin Fang

Masters Theses

"Digital/Analog ground partitioning has been used to isolate noisy digital and power current from sensitive analog currents in high-speed multiplayer printed circuit boards. The through-hole signal via enables convenient routing and component placement on the PCB and is used for signal interconnections when the signal traces are changing the layers. This design, however, breaks the current return path for signal traces that cross the two separated grounds, which causes undesired effects such as signal distortion and radiated emission.

Electromagnetic mechanism associated with them needs to be understood to control and suppress these undesired effects. In this paper, we have investigated …

Predicting Radiated Emissions From A Cable Harness Through Component Level Tests, Fuwei Ma

Masters Theses

“In this work, a procedure is developed to predict the radiated emissions from a cable harness using component-level tests. Direct measurement on the engine control unit is utilized to accurately characterize the equivalent common mode source voltages and impedance associated with the device. The cable harness geometry is reduced using the equivalent cable bundle approach by lumping wires according to the source and load impedance compared with characteristic impedance of the harness, which dramatically reduces the measurement effort and allows practical 3D full-wave simulation of the radiated emissions. Radiated emissions are predicted from an engine control unit (ECU) and an …

Partial Discharge Testing And Detection Under Pwm Voltage, John Meadors

Masters Theses

Partial Discharge detection and measurement is an important part of electric insulation design. However, in PWM (pulse width modulation) voltage source converter environments, the noise resulting from switching voltage (rise and fall times of tens of nanoseconds) makes detection and extraction of partial discharge difficult. Unique methods of partial discharge detection are needed to address and decouple the noise from partial discharge measurements. PWM voltage can feature high switching speeds and high dv/dt during voltage switching. These PWM voltage behaviors are not found in traditional utility high voltage applications, and the effects that this type of voltage has on insulation …

Evaluation Of Robust Deep Learning Pipelines Targeting Low Swap Edge Deployment, David Carter Cornett

Masters Theses

The deep learning technique of convolutional neural networks (CNNs) has greatly advanced the state-of-the-art for computer vision tasks such as image classification and object detection. These solutions rely on large systems leveraging wattage-hungry GPUs to provide the computational power to achieve such performance. However, the size, weight and power (SWaP) requirements of these conventional GPU-based deep learning systems are not suitable when a solution requires deployment to so called "Edge" environments such as autonomous vehicles, unmanned aerial vehicles (UAVs) and smart security cameras.

The objective of this work is to benchmark FPGA-based alternatives to conventional GPU systems that have the …

Design And Simulation Of A Supervisory Control System For Hybrid Manufacturing, Michael Buckley

Masters Theses

The research teams of Dr. Bill Hamel, Dr. Bradley Jared and Dr. Tony Schmitz were tasked by the Office of Naval Research to create a hybrid manufacturing process for a reduced scale model of a naval ship propeller. The base structure of the propeller is created using Wire Arc Additive Manufacturing (WAAM), which is then scanned to compare created geometry to desired geometry. The propeller is then machined down to match the desired geometry. This process is iterated upon until the final product meets design tolerances. Due to the complex nature and numerous industrial machines used in the process, it …

High Frequency Injection Sensorless Control For A Permanent Magnet Synchronous Machine Driven By An Fpga Controlled Sic Inverter, Jared Walden

Masters Theses

As motor drive inverters continue to employ Silicon Carbide (SiC) and Gallium Nitride (GaN) devices for power density improvements, sensorless motor control strategies can be developed with field-programmable gate arrays (FPGA) to take advantage of high inverter switching frequencies. Through the FPGA’s parallel processing capabilities, a high control bandwidth sensorless control algorithm can be employed. Sensorless motor control offers cost reductions through the elimination of mechanical position sensors or more reliable electric drive systems by providing additional position and speed information of the electric motor. Back electromotive force (EMF) estimation or model-based methods used for motor control provide precise sensorless …

Development Of An Encrypted Wireless System For Body Sensor Network Applications, Kendra Anderson

Masters Theses

Wireless body area networks (WBAN), also called wireless body sensor networks (WBSN), consist of a collection of wireless sensor nodes used to monitor and assess various human physiological conditions, which can then be used by healthcare professionals to help them make important healthcare decisions. They can be used to prevent disease, help diagnosis a disease, or manage the symptoms of a disease. An extremely important aspect of WBAN is security to protect a patient's healthcare information, as a hacker could potentially cause fatal harm. Current security measures are implemented in software at the MAC layer and higher, not in the …

Power System Stability Assessment With Supervised Machine Learning, Mirka Mandich

Masters Theses

Power system stability assessment has become an important area of research due to the increased penetration of photovoltaics (PV) in modern power systems. This work explores how supervised machine learning can be used to assess power system stability for the Western Electricity Coordinating Council (WECC) service region as part of the Data-driven Security Assessment for the Multi-Timescale Integrated Dynamics and Scheduling for Solar (MIDAS) project. Data-driven methods offer to improve power flow scheduling through machine learning prediction, enabling better energy resource management and reducing demand on real-time time-domain simulations. Frequency, transient, and small signal stability datasets were created using the …

Modeling And Evaluation Of Utility-Scale Microgrid Investment For Distribution System Planning, Ian Schomer

Masters Theses

The electrical distribution network faces two great challenges for the immediate future. First, increased affordability of distributed energy resources (DERs)—and advancing control technologies of inverters that interface them to the grid—have driven a shift from a passive to an active distribution network (ADN), which heightens the complexity of system management. Second, the increased frequency of severe weather events and increased potential for a cybersecurity attack necessitate the need for a resilient infrastructure that can respond adaptively to shutdowns within the system. Microgrids (MGs) present a promising framework both to provide hierarchal control of DERs and to increase resiliency with grid-forming …

Development Of A Point-Of-Use Testing Platform For Detecting Bacteria Infection In Raw Milk, Xin Xia

Masters Theses

The detection and quantification of bacteria are essential to environment and food quality monitoring. Escherichia coli (E. coli) is a common pathogen, also a causative agent of mastitis. Traditional methods usually require samples to be tested in a laboratory. However, sending samples to remote lab increases the cost of time and money spent on delivery. Sometimes, samples can degrade during this long progress and cause inaccuracy. A low cost and reusable sensor is designed to perform on-site quantification. The sensor composed of two layers of asymmetrical mesh electrodes, which is used in coordination magnetic microparticles functionalized with bacterium-specific antibody. Immunological …

Development Of A Highly Sensitive Pressure Sensing System With Custom-Built Software For Continuous Physiological Measurements, Masoud Panahi

Masters Theses

In this work, a pressure sensing system was designed and fabricated by developing a highly sensitive cone-structured pressure sensor with a custom-built software for physiological monitoring applications. A novel highly sensitive cone structured porous polydimethylsiloxane (PDMS) based pressure sensor capable of detecting very low-pressure ranges was developed for respiration monitoring. The pressure sensor was fabricated using a master mold, a hybrid-structured dielectric layer, and fabric-based electrodes. The master mold with inverted cone structures was created using a rapid and precise three-dimensional (3D) printing technique. The dielectric layer, with pores and cone structures, was prepared by annealing a mixture of PDMS, …

A Secure Architecture For Defense Against Return Address Corruption, Grayson J. Bruner

Masters Theses

The advent of the Internet of Things has brought about a staggering level of inter-connectivity between common devices used every day. Unfortunately, security is not a high priority for developers designing these IoT devices. Often times the trade-off of security comes at too high of a cost in other areas, such as performance or power consumption. This is especially prevalent in resource-constrained devices, which make up a large number of IoT devices. However, a lack of security could lead to a cascade of security breaches rippling through connected devices. One of the most common attacks used by hackers is return …

Development Of A Converter-Based Testing Platform And Battery Energy Storage System (Bess) Emulator For Microgrid Controller Function Evaluation, Dingrui Li

Masters Theses

The microgrid has attracted increasing research attention in the last two decades. Due to the development of renewable energy resources and power electronics technologies, the future microgrid will trend to be smarter and more complicated. The microgrid controller performs a critical role in the microgrid operation, which will also become more and more sophisticated to support the future microgrid. Before final field deployment and test, the evaluation and testing of the controller is an indispensable step in the controller development, which requires a proper testing platform.

However, existing simulation-based platforms have issues with potential numerical oscillation and may require huge …

Optimal And Model Free Control Of Tumor Immune Interaction Dynamic To Schedule Cancer Treatments, Mohamed Alsager

Masters Theses

Cancer is an intricate disease that can attack different parts of the human body. In the most common types of cancer, abnormal cells divide uncontrollably and impair body tissue. Cross disciplinary research has long aided expansion of our knowledge and ability to approach problems with a different perspective. Engineers and clinicians can collaborate to solve mysteries surrounding cancer cells function and responses. Engineers have contributed to cancer treatment, by studying new ways to diagnose and treat cancer. According to a study by John Hopkins university engineered Nano-particles can induce immune reaction and kill cancer cells. In addition, new ways of …

A Communications Testbed For Testing Power Electronic Agent Systems, Benjamin R. Dean

Masters Theses

As power electronic system (PES) continue to incorporate complex intra-system communication, understanding and characterizing this communication has become a complex task. Knowing how a system’s communication will behave is vital to ensuring proper operation of these systems. This thesis proposes and outlines a communication testbed that streamlines the development and testing of the communications between the components of PES, and further presents the characterization of communication protocol utilized in these multi-agent PESs. These communication protocols include MQTT, Modbus, or User Datagram Protocol (UDP). Understanding the different behavior of these protocols presents is paramount for the design of PESs.

Method Of Optimal Battery Scheduling With Optimal Battery And Photovoltaic Sizing, Gideon Hallman

Masters Theses

“Renewable energy generation is on the rise. One of the best ways to capitalize on this intermittent power supply is by using the renewable energy source in tandem with batteries. A joint photovoltaic (PV) and battery system model was created that implemented battery degradation and optimized battery usage using a Markov Decision Process (MDP). This system was then subjected to a series of tests to do a sensitivity analysis while optimizing the battery and PV sizing for the system at hand. Parametric sweeps of solar power and battery capital costs, the cost of energy taken from the grid, the cost …

Seed Modeling Of An Esd Gun Discharge To A Usb Cable, Yang Xu

Masters Theses

“An IC protected by a transient voltage suppression (TVS) diode may fail if the TVS device does not turn on or does not turn on quickly enough, causing the IC to take the full brunt of the electrostatic discharge (ESD) event. Transient simulation models have been developed for ESD protection devices for the purpose of system-efficient ESD design (SEED). The TVS modeling methodology has been improved to better represent the physics that occurs during the TVS response and more accurately predict the interactions between off-chip and on-chip protection devices. Moreover, a complicated test scenario -- an ESD gun discharge through …

The Field Coupling Mechanism Study For Near Field Probe, Shun Liu

Masters Theses

"In this part, the radius of the loop is used to predict the voltage induced by the E- field in the circular loop antenna. The thin rectangle loop and thick rectangle loop have been investigated. The equivalent radius of the rectangle loop is estimated by the average of the one over the distance between the points on the loop to the center of the loop. The estimation matches with the numerical simulation"--Abstract, page iv.

A Simple Background Elimination Method For Miniaturized Fiber-Optic Raman Probe, Bohong Zhang

Masters Theses

"Raman scattering is called a photonic - molecular interaction based on the kinetic model of the analytic. Due to the uniqueness of the Raman scattering technique, it can provide a unique fingerprint signal for molecular recognition. However, a serious challenge often encountered in Raman measurement comes from the requirements of fast, real-time remote sensing, background fluorescence suppression, and micro-environmental detection.

A new Miniaturized Fiber-Optic Raman Probe (MFORP) for Raman spectroscopy, used especially for eliminating background fluorescence and enhancing sampling, is presented. Its main purpose is to provide an overview of excellent research on the detection of very small substances and …

A Physics-Based Pi Pre-Layout Tool For Pcb Pdn Design, Shuang Liang

Masters Theses

"With increasingly stringent requirements for lower voltage supply, and higher density in PCB PDN design, now integrity (PI) is an increasingly important aspect that must be considered. A pre-layout tool based on the Cavity Model and Boundary Element Method is built to automatically achieve a specified target impedance for a multi-layered Printed Circuit Board (PCB) Power Distribution Network (PDN) design with a minimal number of decoupling capacitors.

The pre-work about the post-layout design and analysis is proposed and the guidelines for creating a decoupling capacitors network with better performance has been built. With limit inputs, physical limitations for the minimal …

Design And Evaluation Of The 3d Printed Electromagnetic Absorber Built With Conductive Carbon-Filled Filament, Rui Mi

Masters Theses

"This research presents an application of the resistive frequency selective surface (FSS) fabricated with a 3D printed conductive material as an electromagnetic absorber for the EMI-reducing door. This solution allows to reduce radiated emissions of a router system. The resistive frequency selective surface has a three-layer structure. The top layer is a 3D printed FSS pattern, the middle layer is an air gap, and the bottom layer is a metal plane.

The first paper presents the methodology for manufacturing a frequency selective surface using the 3D printing technology, including the material characterization, design, fabrication, and evaluation.

The unpublished content presents …

Transfer Function Measurement For Automotive Intentional Emi And Thermal Runaway Investigation Of Lithium-Ion Battery By Intentional Emi, Woncheol Song

Masters Theses

"With an increasing demand for electric vehicles and autonomous driving, many components of a vehicle are being replaced as electric components. This implicates the possibility of an increase in the malfunction of electric components due to unknown electromagnetic interferences. In this reason, malicious intentional electromagnetic interference (IEMI) is being considered as a growing threat for the current and next generation of automotive technology.

In the first topic, the transfer function between the IEMI attacker and the engine control unit (ECU) circuit in an automobile is extracted to analyze how the IEMI affects the vehicle.

In the second topic, to mimic …

Bond Graph Modeling Of Critical Infrastructures For Cyber-Physical Security Implementation, Michele Jane White

Masters Theses

“In developed societies, there exists infrastructure vital to everyday life. This includes water and power systems. Technology is quickly evolving and being implemented on these utilities. This technology can range from smart metering in neighborhoods to volume sensors in local waste water treatment facilities. When networking, sensing, monitoring, or control devices are integrated with infrastructure it is considered a cyber physical system, or CPS. When information about an important physical system is connected to the virtual world, it is opened up to security risks. Cyber security can be provided to the CPS by monitoring the physical state of the system …

A Compact Wavelength Meter Using A Multimode Fiber, Ogbole Collins Inalegwu

Masters Theses

“Wavelength meters are very important for precision measurements of both pulses and continuous-wave optical sources. Conventional wavelength meters employ gratings, prisms, interferometers, and other wavelength-sensitive materials in their design. Here, we report a simple and compact wavelength meter based on a section of multimode fiber and a camera. The concept is to correlate the multimodal interference pattern (i.e., speckle pattern) at the end-face of a multimode fiber with the wavelength of the input lightsource. Through a series of experiments, specklegrams from the end face of a multimode fiber as captured by a charge-coupled device (CCD) camera were recorded; the images …

Analysis And Design Of Dc-Link Capacitor In Cascaded H-Bridge Multilevel Active Front-End Converter, Muhammad Shehroz Malik

Masters Theses

Medium-voltage grid-tied systems often use a cascaded H-bridge multi-level active front-end. In this converter, dc link bus capacitors play an important role in stabilizing the converter and enabling both active and reactive power injections. The present work provides analytical expressions for the capacitor current, which are essential for optimizing system design (especially capacitor size vs. lifetime). Then, the expression is incorporated into the grid connected bidirectional power system model. Consequently, this work contributes to the guiding principles to choose accurate dc link capacitor ratings against grid-side power delivery requirements.

DC-link capacitors come with an expiration date which is dependent on …

Physics-Based Modeling Of Lithium-Ion Batteries For Control And Estimation Applications, Brody J. C. Riemann

Masters Theses

“Lithium-ion batteries are extensively used in many application areas like consumer electronics, electric vehicles, and microgrids. As the world moves towards further electrification of vehicles and more widespread use of renewable energy sources, the need for large-scale battery storage systems will grow. To effectively replace conventional methods, batteries will need to be charged quickly while accounting for degradation to maximize lifetime. Further, larger batteries require more detailed safety monitoring, which is implemented using a battery management system (BMS). A BMS is responsible for state of charge (SOC) estimation, state of health (SOH) estimation, cell balancing, regulating voltage and current according …

Design Of Power Receiving Units For 6.78mhz Wireless Power Transfer Systems, Hoang Phuc Tran Pham

Masters Theses

In the last decade, the wireless power transfer (WPT) technology has been a popular topic in power electronics research and increasingly adopted by consumers. The AirFuel WPT standard utilizes resonant coils to transfer energy at 6.78 MHz, introducing many benefits such as longer charging distance, multi-device charging, and high tolerance of the coil misalignment. However, variations in coil coupling due to the change in receiving coil positions alter the equivalent load reactance, degrading efficiency.

In recent studies, active full-bridge rectifiers are employed on WPT receivers because of their superior efficiency, controllability, and ability to compensate for detuned WPT networks. In …

Camera-Based Remote Photoplethysmography For Estimation Of Heart Rate Using Single Board Computers, Benjamin Sweely

Masters Theses

The objective of this project was to develop a wireless, noncontact monitoring system that measures multiple physiological parameters in human faces from a distance using a camera. Compared to traditional sensors, this monitoring system does not use wires or adhesives, providing a safer, more user-friendly application. The goal of the monitoring systems was to estimate heart rate (HR). The current practices of measuring HR involve collecting electrocardiogram (ECG) signals from adhesive electrodes placed on various parts of the body and using a pulse oximeter (PO) typically placed on the ear lobe or finger. We were able to successfully create 2 …