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Full-Text Articles in Engineering

Integrated Circuit Wear-Out Prediction And Recycling Detection Using Radio-Frequency Distinct Native Attribute Features, Randall D. Deppensmith Dec 2016

Integrated Circuit Wear-Out Prediction And Recycling Detection Using Radio-Frequency Distinct Native Attribute Features, Randall D. Deppensmith

Theses and Dissertations

Radio Frequency Distinct Native Attribute (RF-DNA) has shown promise for detecting differences in Integrated Circuits(IC) using features extracted from a devices Unintentional Radio Emissions (URE). This ability of RF-DNA relies upon process variation imparted to a semiconductor device during manufacturing. However, internal components in modern ICs electronically age and wear out over their operational lifetime. RF-DNA techniques are adopted from prior work and applied to MSP430 URE to address the following research goals: 1) Does device wear-out impact RF-DNA device discriminability?, 2) Can device age be continuously estimated by monitoring changes in RF-DNA features?, and 3) Can device age state …


Study Of Computational Image Matching Techniques: Improving Our View Of Biomedical Image Data, Ahmadreza Baghaie Dec 2016

Study Of Computational Image Matching Techniques: Improving Our View Of Biomedical Image Data, Ahmadreza Baghaie

Theses and Dissertations

Image matching techniques are proven to be necessary in various fields of science and engineering, with many new methods and applications introduced over the years. In this PhD thesis, several computational image matching methods are introduced and investigated for improving the analysis of various biomedical image data. These improvements include the use of matching techniques for enhancing visualization of cross-sectional imaging modalities such as Computed Tomography (CT) and Magnetic Resonance Imaging (MRI), denoising of retinal Optical Coherence Tomography (OCT), and high quality 3D reconstruction of surfaces from Scanning Electron Microscope (SEM) images. This work greatly improves the process of data …


Improving The Speech Intelligibility By Cochlear Implant Users, Behnam Azimi Dec 2016

Improving The Speech Intelligibility By Cochlear Implant Users, Behnam Azimi

Theses and Dissertations

In this thesis, we focus on improving the intelligibility of speech for cochlear implants (CI) users. As an auditory prosthetic device, CI can restore hearing sensations for most patients with profound hearing loss in both ears in a quiet background. However, CI users still have serious problems in understanding speech in noisy and reverberant environments. Also, bandwidth limitation, missing temporal fine structures, and reduced spectral resolution due to a limited number of electrodes are other factors that raise the difficulty of hearing in noisy conditions for CI users, regardless of the type of noise. To mitigate these difficulties for CI …


Solid State Protective Device Topological Trade-Offs For Mvdc Systems, Vikas Singh Dec 2016

Solid State Protective Device Topological Trade-Offs For Mvdc Systems, Vikas Singh

Theses and Dissertations

Presently accepted approaches to protection are “Unit-Based” which means the power converter(s) feeding the bus coordinate with no-load electromechanical switches to isolate faulted portions of the bus. However, “Breaker-Based” approaches, which rely upon solid state circuit breakers for fault mitigation can result in higher reliability of power and potentially higher survivability. The inherent speed of operation of solid state protective devices will also play a role in fault isolation, hence reducing stress level on all system components. A comparison study is performed of protective device topologies that are suitable for shipboard distribution systems rated between 4kVdc and 20kVdc from the …


Probabilistic Reliability Analysis Of Electric Power Systems With Smart Grid Technologies And Water Distribution Networks: Modeling, Assessment, And Comparison, Ruosong Xiao Aug 2016

Probabilistic Reliability Analysis Of Electric Power Systems With Smart Grid Technologies And Water Distribution Networks: Modeling, Assessment, And Comparison, Ruosong Xiao

Theses and Dissertations

With the rapid growth of population, the modern human society is becoming more and more dependent on the proper operation of critical infrastructures - the interconnected electrical power system, the drinking water distribution and supply system, the natural gas transmission and distribution system, and so forth. It has become an important issue to maintain reliable functions of these critical systems. As a result, comprehensive reliability evaluation is highly needed to quantify their reliability in an objective manner. Conventionally, deterministic criteria were used in reliability evaluations. However, it lacked the ability to model and quantify the stochastic nature of system behaviors …


Transient Control Of Synchronous Machine Active And Reactive Power In Micro-Grid Power Systems, Luke Gerard Weber Aug 2016

Transient Control Of Synchronous Machine Active And Reactive Power In Micro-Grid Power Systems, Luke Gerard Weber

Theses and Dissertations

There are two main topics associated with this dissertation. The first is to investigate

phase–to–neutral fault current magnitude occurring in generators with multiple zero–sequence

current sources. The second is to design, model, and tune a linear control system for oper-

ating a micro–grid in the event of a separation from the electric power system.

In the former case, detailed generator, AC8B excitation system, and four–wire electric

power system models are constructed. Where available, manufacturers data is used to

validate the generator and exciter models. A gain–delay with frequency droop control

is used to model an internal combustion engine and governor. …


Deep Tissue Light Delivery And Fluorescence Tomography With Applications In Optogenetic Neurostimulation, Mehdi Azimipour Aug 2016

Deep Tissue Light Delivery And Fluorescence Tomography With Applications In Optogenetic Neurostimulation, Mehdi Azimipour

Theses and Dissertations

Study of the brain microcircuits using optogenetics is an active area of research. This method has a few advantages over the conventional electrical stimulation including the bi-directional control of neural activity, and more importantly, specificity in neuromodulation. The first step in all optogenetic experiments is to express certain light sensitive ion channels/pumps in the target cell population and then confirm the proper expression of these proteins before running any experiment. Fluorescent bio-markers, such as green fluorescent protein (GFP), have been used for this purpose and co-expressed in the same cell population. The fluorescent signal from such proteins provides a monitory …


The Study Of Locating Ground Faults In Dc Microgrid Using Wavelet Transform, Ruijing Yang Aug 2016

The Study Of Locating Ground Faults In Dc Microgrid Using Wavelet Transform, Ruijing Yang

Theses and Dissertations

As the proliferations of distributed generation and power electronic equipment in power systems, direct current (DC) microgrid emerged and attracted more and more researchers’ attentions. Protection of DC microgrid is a big challenge and to build a well-function protection system, locating the faults accurately is a critical issue. It is easy to find the location of short circuit faults in DC microgrid. However, it is difficult to locate ground faults in DC microgrid because of the spray capacitors and the large amount of distributed resources.

In this thesis, Wavelet Transform is applied to decompose the common mode currents that is …


Wireless Power Transfer Using Class-De Converter Via Strongly Coupled Two Planar Coils, Ayetullah Bahadir Biten Aug 2016

Wireless Power Transfer Using Class-De Converter Via Strongly Coupled Two Planar Coils, Ayetullah Bahadir Biten

Theses and Dissertations

WIRELESS POWER TRANSFER USING CLASS-DE CONVERTER

VIA

STRONGLY COUPLED TWO PLANAR COILS

by

Ayetullah Bahadir Biten

The University of Wisconsin – Milwaukee, August 2016

Under the supervision of Professor Adel Nasiri

Wireless power systems are getting popular with the improvement in the technology not just because it is a fancy and cool conception but also because it is more convenient and safer in some applications. For example, this project aims to help high power data center design to be changed to wirelessly powered center to provide a safe and hands-on work environment even under different load conditions. Thinking of the …


Design, Implementation, And Evaluation Of A Fluorescence Laminar Optical Tomography Scanner For Brain Imaging, Mahya Sheikhzadeh May 2016

Design, Implementation, And Evaluation Of A Fluorescence Laminar Optical Tomography Scanner For Brain Imaging, Mahya Sheikhzadeh

Theses and Dissertations

Implementation of new instrumentation and techniques for neuroscience research in recent years has opened new avenues in the study of the dynamics of large-scale neural networks such as the brain. In many of these techniques, including fluorescence recordings and optogenetic stimulation, a combination of photonics and molecular genetic methods are exploited to manipulate and monitor neural activities. Such techniques have been proven to be highly efficient in unraveling the mysteries of data processing in the micro circuits of the brain and as a result these techniques are widely used nowadays in most neuroscience labs.

In optogenetics, cell-types of interest are …


A New Paradigm Of Maximizing The Wind And Solar Penetration– A Economical Assessment, Yuming Chen May 2016

A New Paradigm Of Maximizing The Wind And Solar Penetration– A Economical Assessment, Yuming Chen

Theses and Dissertations

Wind and solar energies are the most potential and widely-used renewable energies. But in most cases these energies cannot be maximized because of transmission line capacity and their remote location. Therefore, this thesis proposes a new paradigm which using battery transportation and logistics instead of transmission line, to maximize wind and solar energies. The main focus of this work is to investigate the economical feasibilities of this new paradigm.

In the first part, different models and application are presented. The purpose is finding an appropriate model which can make full use of existing grid resources such as transmission line and …


Monitoring Cellular Metabolism With Near-Infrared Spectroscopy, Jeffrey Jay Sugar May 2016

Monitoring Cellular Metabolism With Near-Infrared Spectroscopy, Jeffrey Jay Sugar

Theses and Dissertations

Aims: Although NIRS oximetry has been widely used in clinical and research settings to monitor oxygen consumption in muscles (1), it is not necessarily able to obtain cellular metabolic levels directly. Oxygen saturation will only change with aerobic metabolism (2); however, anaerobic metabolism cannot be assessed by monitoring oxygen saturation. This work aims to measure cell oxygenation and blood oxygenation, simultaneously, by applying oximetry to hemoglobin/deoxyhemoglobin and to cytochrome c oxidase (CCOX). A custom build NIRS device called the cytoximeter was constructed to achieve this goal. This work could have important impacts on monitoring neurological diseases, Postural Tachycardia Syndrome (POTS), …


The Effects Of Geomagnetic Disturbances On Electrical Power Systems, Benjamin J. Hynes May 2016

The Effects Of Geomagnetic Disturbances On Electrical Power Systems, Benjamin J. Hynes

Theses and Dissertations

Solar storms that generate coronal mass ejections are a cause for concern due to the damage that they cause in high voltage power grids. Geomagnetically induced currents can be introduced onto the grid and cause many adverse effects. The vulnerability of the bulk electric power systems to such events has increased during the past few decades because the power system transmission lines have become more interconnected and have increased in length. Real and reactive power flows, voltage fluctuations, frequency shifts, undesired relay operations, higher order harmonic currents, undesired damage to assets and failure of assets are all possible outcomes from …


Coding Strategies For Cochlear Implants Under Adverse Environments, Qudsia Tahmina May 2016

Coding Strategies For Cochlear Implants Under Adverse Environments, Qudsia Tahmina

Theses and Dissertations

Cochlear implants are electronic prosthetic devices that restores partial hearing in patients with severe to profound hearing loss. Although most coding strategies have significantly improved the perception of speech in quite listening conditions, there remains limitations on speech perception under adverse environments such as in background noise, reverberation and band-limited channels, and we propose strategies that improve the intelligibility of speech transmitted over the telephone networks, reverberated speech and speech in the presence of background noise. For telephone processed speech, we propose to examine the effects of adding low-frequency and high- frequency information to the band-limited telephone speech. Four listening …


Improved Attribute-Based Encryption With Fpga For Automatic Appliance Control Application In Smart Grid, Xueqing Wang May 2016

Improved Attribute-Based Encryption With Fpga For Automatic Appliance Control Application In Smart Grid, Xueqing Wang

Theses and Dissertations

In this thesis, the author describes the privacy violation issues in smart grid with Automatic Appliance Control applications, and explains the security threats related to it. The smart grid is a sensitive and sophisticated system in real life operation. A mass of data including the remote control commands and users’ energy consumptions is transmitted between the utility companies and other devices in the smart grid such as the substations, smart meters, smart home appliances and much more. Without efficient cryptographic methods, an adversary may hack into the data or the remote control commands and extrapolates a resident’s activity model. Therefore, …


Design And Optimization Of Hybrid Energy Storage For Photovoltaic Power Fluctuation Smoothing Based On Frequency Analysis, Ruirui Yang May 2016

Design And Optimization Of Hybrid Energy Storage For Photovoltaic Power Fluctuation Smoothing Based On Frequency Analysis, Ruirui Yang

Theses and Dissertations

A proper design of energy storage system (ESS) can effectively smooth the photovoltaic (PV) output power fluctuation, lower the cost, and improve the power quality and stability.

According to the response characteristics of different energy storage equipment, an optimal hybrid EES sizing method is proposed based on frequency analysis. A hybrid ESS including lead-acid battery, lithium battery and electric double-layer capacitor (EDLC) is selected to smooth out PV power fluctuation and meet both power and energy requirement of the power grid. Fast Fourier Transform (FFT) method is applied for analyzing the spectrum of unwanted PV fluctuation. From the FFT analysis, …


Analysis, Design And Implementation Of A Resonant Solid State Transformer, Mohamad Zouheir Sabbah May 2016

Analysis, Design And Implementation Of A Resonant Solid State Transformer, Mohamad Zouheir Sabbah

Theses and Dissertations

This thesis discusses the design of a full-bridge resonant LLC Solid State Transformer. The proposed topology uses a high-frequency transformer which helps minimizing its cost and size, and enables operating at varying load conditions. By using a resonant circuit, soft switching is achieved. Commutation techniques are discussed, namely ZVS and ZCS. Both concepts are applied on different legs of the H-bridge. Pulse frequency modulation (PFM) and Phase Shifting Modulation (PSM) are utilized to control this resonant converter. One of the requirements of this work is to achieve a tightly regulated DC bus voltage. This was shown to be achieved using …


Electromagnetic Characterization Of Materials Using A Dual Chambered High Temperature Waveguide, Jeffrey S. Sovern Mar 2016

Electromagnetic Characterization Of Materials Using A Dual Chambered High Temperature Waveguide, Jeffrey S. Sovern

Theses and Dissertations

Measurement of the electromagnetic properties of materials at high temperatures is important for industrial, scientific, medical, and aerospace applications [1]. Current high-temperature electromagnetic material characterization is a time consuming process that typically requires three days to collect data from one material specimen. For example, the standard high-temperature process involving rectangular waveguides [2] requires measurements of the sample (1), the empty waveguide (2), and a metal short standard (3) completed in separate heated runs over three days to perform the Nicolson-Ross-Weir inversion algorithm for computing permittivity and permeability. The technique developed here will reduce the high-temperature measurement process from three days …


Hybrid Straintronics-Spintronics: Energy-Efficient Non-Volatile Devices For Boolean And Non-Boolean Computation, Ayan K. Biswas Jan 2016

Hybrid Straintronics-Spintronics: Energy-Efficient Non-Volatile Devices For Boolean And Non-Boolean Computation, Ayan K. Biswas

Theses and Dissertations

Research in future generation computing is focused on reducing energy dissipation while maintaining the switching speed in a binary operation to continue the current trend of increasing transistor-density according to Moore’s law. Unlike charge-based CMOS technology, spin-based nanomagnetic technology, based on switching bistable magnetization of single domain shape-anisotropic nanomagnets, has the potential to achieve ultralow energy dissipation due to the fact that no charge motion is directly involved in switching. However, switching of magnetization has not been any less dissipative than switching transistors because most magnet switching schemes involve generating a current to produce a magnetic field, or spin transfer …


Pattern Recognition In Class Imbalanced Datasets, Nahian A. Siddique Jan 2016

Pattern Recognition In Class Imbalanced Datasets, Nahian A. Siddique

Theses and Dissertations

Class imbalanced datasets constitute a significant portion of the machine learning problems of interest, where recog­nizing the ‘rare class’ is the primary objective for most applications. Traditional linear machine learning algorithms are often not effective in recognizing the rare class. In this research work, a specifically optimized feed-forward artificial neural network (ANN) is proposed and developed to train from moderate to highly imbalanced datasets.

The proposed methodology deals with the difficulty in classification task in multiple stages—by optimizing the training dataset, modifying kernel function to generate the gram matrix and optimizing the NN structure. First, the training dataset is extracted …


Beyond Conventional C-Plane Gan-Based Light Emitting Diodes: A Systematic Exploration Of Leds On Semi-Polar Orientations, Morteza Monavarian Jan 2016

Beyond Conventional C-Plane Gan-Based Light Emitting Diodes: A Systematic Exploration Of Leds On Semi-Polar Orientations, Morteza Monavarian

Theses and Dissertations

Despite enormous efforts and investments, the efficiency of InGaN-based green and yellow-green light emitters remains relatively low, and that limits progress in developing full color display, laser diodes, and bright light sources for general lighting. The low efficiency of light emitting devices in the green-to-yellow spectral range, also known as the “Green Gap”, is considered a global concern in the LED industry. The polar c-plane orientation of GaN, which is the mainstay in the LED industry, suffers from polarization-induced separation of electrons and hole wavefunctions (also known as the “quantum confined Stark effect”) and low indium incorporation efficiency that …


Distributed Optimization And Control Of Islanded Microgrids, Md Rishad Hossain Jan 2016

Distributed Optimization And Control Of Islanded Microgrids, Md Rishad Hossain

Theses and Dissertations

A microgrid may have numerous multi-functional power electronic converters connecting sources, loads, and storage to the system. Systems where converters are the interface between many of the main sources of energy and load centers have the ability to direct the flow of energy if the control of the converters is coordinated. The influence of energy flow in a microgrid by coordinated action of converters is referred to here as ‘energy routing’. Energy routing allows for reduction of systems losses by optimizing source operating points and reducing transmission and distribution path losses. Energy ramp rates at various points in the system …


Miniaturized Rf Components With A Novel Tunable Engineered Substrate For Wireless Communication Systems, Yujia Peng Jan 2016

Miniaturized Rf Components With A Novel Tunable Engineered Substrate For Wireless Communication Systems, Yujia Peng

Theses and Dissertations

There is an increasing demand for reliable sensor system capable of remote sensing and measuring interesting data. Although large communication range can be achieved, active wireless communication systems are still suboptimal in longtime applications due to their harmful battery supply. Inductively coupled passive devices, with the advantages in safe long-term implanting, structural simplicity, small fabrication footprint and low-cost production, are preferred in chronic monitoring, but little work has been done to optimize the performance of these systems, especially under some design constraints.

The model and optimization of an inductively coupled wireless pressure sensor system is presented in this dissertation. With …


Investigation Of Wide Bandgap Semiconductor Devices For Radiation Detection Applications, Rahmi Orhon Pak Jan 2016

Investigation Of Wide Bandgap Semiconductor Devices For Radiation Detection Applications, Rahmi Orhon Pak

Theses and Dissertations

Radioactive materials, as they decay, generate different high-frequency electromagnetic radiation such as alpha particles, beta particles, x-rays, gamma-rays, and neutrons. Nuclear detectors could stop these high-energy ionizing radiations, collect and transport the charges generated to an external circuit, and produce an electrical signal which is amplified by readout electronics to measure the energy of nuclear interaction. Thus, nuclear detectors are important tools for accounting of radioactive materials and have widespread applications in nuclear power plants, nuclear waste management, in national security, in medical imaging such as x-ray mammography, digital chest radiography, CT scan, and in high energy astronomy for NASA …


Simulation Of Gan Based Mis Varactor, Bojidha Babu Jan 2016

Simulation Of Gan Based Mis Varactor, Bojidha Babu

Theses and Dissertations

This work deals with novel microwave switches based on III-Nitride varactors. RF switches, power limiters and other control devices are important components of various RF systems, such as wireless modules of laptops, tablets, cell phones etc., satellites communication systems, radars, multi-band wireless and aerospace communications, phased array antennas and so worth. Traditional RF switches are fabricated using pin diodes or MEMS, Si MOSFETs or GaAs HEMTs. These devices have a number of fundamental limitations. Si or GaAs based devices suffer from a low breakdown voltage and cannot handle high RF power. Pin-diodes require large forward currents and do not allow …


Applications Of Impedance Identification To Electric Ship System Control And Power Hardware-In-The-Loop Simulation, Jonathan Siegers Jan 2016

Applications Of Impedance Identification To Electric Ship System Control And Power Hardware-In-The-Loop Simulation, Jonathan Siegers

Theses and Dissertations

Recent advances in semiconductor technology, controls, and switching converter topologies have resulted in the increasing application of power electronics in power distribution systems. Power electronic enabled distribution systems have inspired a renewed interest in DC distribution architectures as an appealing alternative to traditional AC methods due to the significant performance and efficiency gains they offer. However, the notional power electronic based DC distribution system is a complex and extensively interconnected system consisting of multiple power converters. As a result, a number of system-level challenges related to stability arise due to interaction among multiple power converters. In addition, the power distribution …


High Gain Pattern Reconfigurable Antenna Arrays For Portable And Body-Centric Wireless Applications, Nowrin Hasan Chamok Jan 2016

High Gain Pattern Reconfigurable Antenna Arrays For Portable And Body-Centric Wireless Applications, Nowrin Hasan Chamok

Theses and Dissertations

Wireless devices such as smartphones, tablet computers, smartwatches etc. have become ubiquitous. With that, the demand for high speed data has increased tremendously. Designing antennas for such applications is challenging because of limited availability of space, shadowing or blockage from the human body, and signal loss from multipath fading. Conventional broad, fixed beam low gain antennas result in poor reception, faster battery drainage, and low data rate. Compressed footprint high gain pattern reconfigurable antenna arrays can solve these problems which is the focus of this dissertation. Two innovative high gain pattern reconfiguration techniques, the switched beam parasitic array and the …


A Comparison Of Fpga Implementation Of Latency-Based Solvers For Power Electronic System Real-Time Simulation, Matthew Aaron Milton Jan 2016

A Comparison Of Fpga Implementation Of Latency-Based Solvers For Power Electronic System Real-Time Simulation, Matthew Aaron Milton

Theses and Dissertations

In the design of power systems, real-time simulation is a powerful tool to evaluate and validate designs before dedicating resources to develop such systems. Through use of real-time simulation, one can study the behavior of a power system in interaction with real, physical elements, all while avoiding the cost and risk in constructing and testing such systems before a design is finalized. In recent decades, effort has been made in the industry and academia to apply real-time simulation to that of switching power converters through use of high-speed digital signal processors (DSPs) and field programmable gate array (FPGA) devices. With …


Wireless Channel Modeling For Networks On Chips, William Rayess Jan 2016

Wireless Channel Modeling For Networks On Chips, William Rayess

Theses and Dissertations

The advent of integrated circuit (chip) multiprocessors (CMPs) combined with the continuous reduction in device physical size (technology scaling) to the sub-nanometer regime will result in an exponential increase in the number of processing cores that can be integrated within a single chip. Today’s CMPs already support tens to low hundreds of cores and both industry and academic roadmaps project that future chips will have thousands of cores. Therefore, while there are open questions on how to harness the computing power offered by CMPs, the design of power-efficient and compact on-chip interconnection networks that connects cores, caches and memory controllers …


Engineering Model Of Iii-Nitride Power Heterostructure Field Effect Transistor On Silicon Substrate, Mohammad Mirwazul Islam Jan 2016

Engineering Model Of Iii-Nitride Power Heterostructure Field Effect Transistor On Silicon Substrate, Mohammad Mirwazul Islam

Theses and Dissertations

In modern society, the demand for power consumption is increasing rapidly and the need of energy savings is now an issue of global importance. Highly efficient power converters and power conditioning systems operating with wide range of traditional as well as novel renewable and clean energy sources, are playing crucial role in energy saving. Si converters have already reached their limitation in terms of switching frequency and breakdown voltage/on-resistance ratio. Research is going on all around the world and it is now well accepted that significant improvement in power conversion efficiency and speed can only be achieved using beyond Si …