Engineering Commons^™

Influence Of Materials And Design Parameters On Zinc Oxide Surface Acoustic Devices, Samuel B. Dewhitt

Theses and Dissertations

This thesis presents research into Zinc Oxide (ZnO) based resonators to include Width Extensional Mode (WEM), Length Extensional Mode (LEM), and Surface Acoustic Wave (SAW) devices. The design and operation of ZnO based SAW devices are investigated further to characterize design parameters and operating modes. Their design, fabrication, and results are discussed in detail. SAW device testing in conjunction with X-Ray Diffractometry (XRD) and Atomic Force Microscopy (AFM) are utilized to characterize ZnO and its deposition parameters on a variety of different substrates and interlayers, with different deposition temperatures and annealing parameters. These substrates include silicon, silicon oxide-on-silicon, and sapphire …

Current-Source Dc-Dc Converter For Fiber-Optic Communication Systems, Jissell C. Jose

Master's Theses

In this thesis, a proof of concept for a current-source DC-DC converter for powering sensors used in an underwater communications system is presented. The proposed converter steps down an input current of 0.9 A to 0.625 A, while maintaining an output voltage of 24 V and output power of 15 W. The complete steady-state analysis and design of the proposed converter in its single-stage form is also explained in detail. Performance evaluation of the proposed converter was carried out using LTspice. Results of the simulation demonstrate that the design was able to produce average output current of 0.639 A at …

X-Band Rf Transmitter Design For Multi-Purpose Small Satellite Communication Operations, Omer F. Gumus

Master's Theses

This thesis provides a description of the analysis, design, and tests of an X-band RF Transmitter communication system for small satellites. X-band transmitter systems are becoming popular in the upcoming deep space missions. Most of the deep-space ground stations have been using X-band frequencies to receive or transmit signals. The X-band (<10 GHz) can offer lower atmospheric losses and up to a couple of Mbps data rates for multiple satellite operations. Nowadays, many small satellites have been using frequency bands such as VHF, UHF, L, and S-band frequencies for communication. From deep space to the ground station, the low-frequency ranges are inadequate in providing Mbps level data rates and enough bandwidth for deep space missions.

The main focus of this thesis was the development of the subsystems such as gain block amplifier, Mixer, Bandpass Filter, and RF power amplifier. The subsystems were designed separately, then they were connected together to perform an end-to-end system test. One of the thesis aims is to design …

Reliability Study Of Electrical Distribution System With Local And Interregional Bidirectional Centralized Electric Vehicle Charging Stations, Janine Gian Christii C. Darato

Master's Theses

In this thesis, a method was developed to evaluate the impact of bidirectional electric vehicle (EV) charging on power system reliability using Synergi Electric software. Load profiles, EV availability, EV state-of-charge (SOC) were important factors considered in this study. The analysis in this study is based on local and interregional vehicle-to-grid (V2G) implementation at different load points in the system. In general, local V2G implementation is observed to be more effective in improving system reliability over interregional V2G power flow. System Average Interruption Duration Index (SAIDI) and System Average Interruption Frequency Index (SAIFI) improvements were observed to increase with increasing …

Music Visualization Using Source Separated Stereophonic Music, Hannah Eileen Chookaszian

Master's Theses

This thesis introduces a music visualization system for stereophonic source separated music. Music visualization systems are a popular way to represent information from audio signals through computer graphics. Visualization can help people better understand music and its complex and interacting elements. This music visualization system extracts pitch, panning, and loudness features from source separated audio files to create the visual. Most state-of-the art visualization systems develop their visual representation of the music from either the fully mixed final song recording, where all of the instruments and vocals are combined into one file, or from the digital audio workstation (DAW) data …

Design Of An Automotive Iot Device To Improve Driver Fault Detection Through Road Class Estimation, Matt Murray

Master's Theses

Unsafe driver habits pose a serious threat to all vehicles on the road. This thesis outlines the development of an automotive IoT device capable of monitoring and reporting adverse driver habits to mitigate the occurrence of unsafe practices. The driver habits targeted are harsh braking, harsh acceleration, harsh cornering, speeding and over revving the vehicle. With the intention of evaluating and expanding upon the industry method of fault detection, a working prototype is designed to handle initialization, data collection, vehicle state tracking, fault detection and communication. A method of decoding the broadcasted messages on the vehicle bus is presented and …

Bearing Fault Detection And Classification Using Artificial Neural Networks, Harnak Singh

Master's Theses

Bearings are the essential components of modern rotating machines. Bearing faults can cause severe machine damages or even breakdowns.

In recent years, artificial intelligence and deep learning have been successfully applied to fault detection. In this thesis, convolutional neural networks (CNN) are employed for bearing fault detection and classification. Computer simulations results demonstrate that the CNN based approach is advantageous over the conventional regression model, with an overall accuracy of 99.5%.

Microgrid Laboratory Wind Energy Integration, Vincent Liang

Master's Theses

Cal Poly San Luis Obispo’s Electrical Engineering Department and the Power Energy Institute have developed a microgrid laboratory with various generators, loads, and protection systems over the past several years. To improve and make the Cal Poly microgrid laboratory more realistic, this thesis outlines the process of improving the EE microgrid setup by adding a wind energy generation system via an induction generator, excitation capacitors, and a protection relay. By adding an induction generator, the microgrid system becomes more resilient to sudden power fluctuations by maintaining a stable voltage and frequency when the microgrid is islanded. To test this, a …

Model-Based Design Of An Optimal Lqg Regulator For A Piezoelectric Actuated Smart Structure Using A High-Precision Laser Interferometry Measurement System, Grant P. Gallagher

Master's Theses

Smart structure control systems commonly use piezoceramic sensors or accelerometers as vibration measurement devices. These measurement devices often produce noisy and/or low-precision signals, which makes it difficult to measure small-amplitude vibrations. Laser interferometry devices pose as an alternative high-precision position measurement method, capable of nanometer-scale resolution. The aim of this research is to utilize a model-based design approach to develop and implement a real-time Linear Quadratic Gaussian (LQG) regulator for a piezoelectric actuated smart structure using a high-precision laser interferometry measurement system to suppress the excitation of vibratory modes.

The analytical model of the smart structure is derived using the …

Parallel Higher Order Dgtd And Fetd For Transient Electromagnetic-Circuital-Thermal Co-Simulation, Huan Huan Zhang, Pan Pan Wang, Li (Lijun) Jun Jiang, Wei E.I. Sha, Mei Song Tong, Ying Liu, Wei Jun Wu, Guang Ming Shi

Electrical and Computer Engineering Faculty Research & Creative Works

A hybrid higher order discontinuous Galerkin time-domain (DGTD) method and finite-element time-domain (FETD) method with parallel technique is proposed for electromagnetic (EM)-circuital-thermal co-simulation in this article. For electromagnetic simulation, DGTD method with higher order hierarchical vector basis functions is used to solve Maxwell equation. Circuit simulation is carried out by modified nodal analysis method. For thermal simulation, FETD method with higher order interpolation scalar basis functions is adopted to solve heat conduction equation. To implement electromagnetic-circuital-thermal co-simulation, the electromagnetic and circuital equations are strongly coupled through voltages, currents, and electric fields at the lumped ports first. Then the electromagnetic and …

Distributed Fiber Optic Sensing With Enhanced Sensitivity Based On Microwave-Photonic Vernier Effect, Chen Zhu, Muhammad Roman, Yiyang Zhuang, Jie Huang

Electrical and Computer Engineering Faculty Research & Creative Works

The Vernier Effect Has Been Widely Used in the Field of Measurement and Instrumentation for Sensitivity Enhancement. Single-Point Optical Fiber Sensors based on the Vernier Effect Have Been Extensively Reported in Recent Years. in This Letter, for the First Time, a Distributed Optical Fiber Sensor based on Microwave Photonics with Improved Sensitivity Enabled by the Vernier Effect is Demonstrated. Distributed Sensing is Realized by Interrogating a Fabry–Perot Interferometer (FPI) Array Formed by Cascaded Reflectors Along an Optical Fiber using an Optical Carrier-Based Microwave Interferometry (OCMI) System. a Reference FPI is Also Included in the System. the Interferogram of Each of …

Laser-Scribed Conductive, Photoactive Transition Metal Oxide On Soft Elastomers For Janus On-Skin Electronics And Soft Actuators, Ganggang Zhao, Yun Ling, Yajuan Su, Zanyu Chen, Cherian J. Mathai, Ogheneobarome Emeje, Alexander Brown, Dinesh Reddy Alla, Jie Huang, Chansong Kim, Qian Chen, Xiaoqing He, David Stalla, Yadong Xu

Electrical and Computer Engineering Faculty Research & Creative Works

Laser-assisted fabrication of conductive materials on flexible substrates has attracted intense interests because of its simplicity, easy customization, and broad applications. However, it remains challenging to achieve laser scribing of conductive materials on tissue-like soft elastomers, which can serve as the basis to construct bioelectronics and soft actuators. Here, we report laser scribing of metallic conductive, photoactive transition metal oxide (molybdenum dioxide) on soft elastomers, coated with molybdenum chloride precursors, under ambient conditions. Laser-scribed molybdenum dioxide (LSM) exhibits high electrical conductivity, biocompatibility, chemical stability, and compatibility with magnetic resonance imaging. In addition, LSM can be made on various substrates (polyimide, …

Robust Detection Of Coronary Heart Disease Using Machine Learning Algorithms, Anas Haitham Domyati

Theses

Predicting whether or not someone will get heart or cardiac disease is now one of the most difficult jobs in the area of medicine. Heart disease is responsible for the deaths of about one person per minute in the contemporary age. Processing the vast amounts of data that are generated in the field of healthcare is an important application for data science. Because predicting cardiac disease is a difficult undertaking, there is a pressing need to automate the prediction process to minimize the dangers that are connected with it and provide the patient with timely warning. The chapter one in …

Human Detection From Aerial Imagery For Search And Rescue Operations, Namat Ahmad Bachir

Theses

Mountain recreation is becoming more popular with mountaineering, rock climbing, skiing, mountain biking, hiking, and mushroom picking among the most popular sports. Despite this tendency, there is currently limited research available explaining the rise in search and rescue (SAR), as well as the injuries and illnesses that entail SAR aid in tourist-friendly mountain and desert areas. The objective of a search and rescue operation is to scan the farthest area feasible in the shortest amount of time in order to locate a lost or wounded individual. In the past decade, several new and spectacular uses for drones, including search and …

Skip The Grid: Giving Power To Navajo Nation, Ryan J. Schacherbauer

Construction Management

Skip the Grid is a project organized by Heart of America, a nonprofit, looking to improve the education and overall wellbeing of children and their families. Many residents within Navajo Nation do not have access to continuous power and rely on temporary generators or car battery to obtain any kind of electricity. Heart of America partnered with the Red Mesa School District to identify families that did not have power, which was impacting the children’s ability to complete their online schoolwork. This senior project was comprised of an interdisciplinary team responsible for installing a working solar system on twelve homes …

Look At All Those Big Knobs! Online Audio Technology Discourse And Sexy Gear Fetishes, Eliot Bates, Samantha Bennett

Publications and Research

Despite a predominantly digital, 21st century music production landscape, analogue hardware professional audio technologies persist. In the discoursal throes of the leading online audio technology message forum Gearslutz, such technologies are routinely objectified, sexualized, fetishized and socialized into gear. Situated in a contemporary critical, interdisciplinary framework of fetish, masculinity and sexuality studies, this research interrogates how audio technologies manufactured and intended for music production contexts become sexy. Applying a mixed-mode methodology, including an intensive discourse, image and material-semiotic analysis of an ‘epic’ sexy gear thread, we collated extensive data about technological fetishization. Sexy gear discourse articulates themes of voyeurism, acquisition, …

An Elastic Recommender Process For Cloud Service Recommendation Scalability, Rui-Dong Qi, Jian-Tao Zhou, Zhuowei Wang, Xiaoyu Song

Electrical and Computer Engineering Faculty Publications and Presentations

Cloud computing services are ubiquitous in society and cloud recommender systems play a crucial role in intelligently selecting services for cloud users. Currently, recommendations are static with low scalability. Only one recommendation list is generated at a time and the recommender strategy in the recommendation cycle is not adjustable. This paper presents a new elastic recommender process (ERP) for cloud users. A Markov model is used to characterize the dynamic relationship between different user states. The ERP generates an elastic recommendation that can be used to dynamically adjust the recommender strategy to meet the user's needs based on their browsing …

Designing A Halbach Rotor Magnetic Gear For A Marine Hydrokinetic Generator, Hossein Baninajar, Sina Modaresahmadi, H. Y. Wong, Jonathan Bird, W. Williams, B. Dechant

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents the electromagnetic and mechanical design as well as experimental testing results for a 9.5:1 gear ratio, series connected, coaxial magnetic gear (MG) for use in a marine hydrokinetic generator. A 2-D and 3-D magnetostatic finite element analysis (FEA) sizing analysis was also conducted and a torque density comparison between using a nested or series MG typology is presented. To achieve a high torque density a four-segment per pole-pair Halbach rotor assembly with a unique slotted Halbach magnet arrangement was used that enables the Halbach rotor magnets to be more easily assembled, even with dimensional tolerance inaccuracies. A …

Poster: Indoor Navigation For Visually Impaired People With Vertex Colored Graphs, Pei Du, Nirupama Bulusu

Electrical and Computer Engineering Faculty Publications and Presentations

Visually impaired people face many daily encumbrances. Traditional visual enhancements do not suffice to navigate indoor environments. In this paper, we explore path finding algorithms such as Dijkstra and A* combined with graph coloring to find a safest and shortest path for visual impaired people to navigate indoors. Our mobile application is based on a database which stores the locations of several spots in the building and their corresponding label. Visual impaired people select the start and destination when they want to find their way, and our mobile application will show the appropriate path which guarantees their safety.

Effects Of Motion Measurement Errors On Radar Target Detection, Darnell D. Parker

Theses and Dissertations

This thesis investigates the relationships present between signal-to-clutter ratios, motion measurement errors, image quality metrics, and the task of target detection, in order to discover what factor merit greater focus in order to attain the highest probability of target detection success. This investigation is accomplished by running a high number of Monte Carlo trials through a coherent target detector and analyzing the results. The aforementioned relationships are demonstrated via sample synthetic aperture radar imagery, histograms, receiver operating characteristics curves, and error bar plots.

Theory And Design Of A Highly Compressed Dropped-Channel Polarimetric Synthetic Aperture Radar, John T. Becker

Theses and Dissertations

Compressed sensing (CS) is a recent mathematical technique that leverages the sparsity in certain sets of data to solve an underdetermined system and recover a full set of data from a sub-Nyquist set of measurements of the data. Given the size and sparsity of the data, radar has been a natural choice to apply compressed sensing to, typically in the fast-time and slow-time domains. Polarimetric synthetic aperture radar (PolSAR) generates a particularly large amount of data for a given scene; however, the data tends to be sparse. Recently a technique was developed to recover a dropped PolSAR channel by leveraging …

Full Pattern Analysis And Comparison Of The Center Fed And Offset Fed Cassegrain Antennas With Large Focal Length To Diameter Ratios For High Power Microwave Transmission, Derek W. Mantzke

Theses and Dissertations

High power microwaves (HPM) have been a topic of research since the Cold War era. This paper will present a comparison between two Cassegrain-type antennas: the axially, or center fed, and the offset fed. Specifically, the 10 GHz operating frequency will be investigated with large focal length to diameter () ratios. Beam patterns which encompass the entire radiation pattern will be included for data validation and optimization. The simulations will follow a design of experiments factorial model to ensure all possible combinations of prescribed parameters are included, including an analysis of variance (ANOVA) study to find parameter influence on the …

One-Stage Blind Source Separation Via A Sparse Autoencoder Framework, Jason Anthony Dabin

Dissertations

Blind source separation (BSS) is the process of recovering individual source transmissions from a received mixture of co-channel signals without a priori knowledge of the channel mixing matrix or transmitted source signals. The received co-channel composite signal is considered to be captured across an antenna array or sensor network and is assumed to contain sparse transmissions, as users are active and inactive aperiodically over time. An unsupervised machine learning approach using an artificial feedforward neural network sparse autoencoder with one hidden layer is formulated for blindly recovering the channel matrix and source activity of co-channel transmissions. The BSS sparse autoencoder …

Optimizing Speed Profiles For Sustainable Train Operation With Wayside Energy Storage Systems, Leon A. Allen

Dissertations

Large hauling capability and low rolling resistance has put rail transit at the forefront of mass transportation mode sustainability in terms of congestion mitigation and energy conservation. As such, rail vehicles are one of the least energy-intensive modes of transportation and least environmentally polluting. Despite, these positives, improper driving habits and wastage of the braking energy through dissipation in braking resistors result in unnecessary consumption, extra costs to the operator and increased atmospheric greenhouse gas emissions.

This study presents an intelligent method for the optimization of the number and locations of wayside energy storage system (WESS) units that maximize the …

Improving The Performance And Evaluation Of Computer-Assisted Semen Analysis, Ji-Won Choi

Dissertations

Semen analysis is performed routinely in fertility clinics to analyze the quality of semen and sperm cells of male patients. The analysis is typically performed by trained technicians or by Computer-Assisted Semen Analysis (CASA) systems. Manual semen analysis performed by technicians is subjective, time-consuming, and laborious, and yet most fertility clinics perform semen analysis in this manner. CASA systems, which are designed to perform the same tasks automatically, have a considerable market share, yet many studies still express concerns about their accuracy and consistency. In this dissertation, the focus is on detection, tracking, and classification of sperm cells in semen …

Outdoor Operations Of Multiple Quadrotors In Windy Environment, Deepan Lobo

Dissertations

Coordinated multiple small unmanned aerial vehicles (sUAVs) offer several advantages over a single sUAV platform. These advantages include improved task efficiency, reduced task completion time, improved fault tolerance, and higher task flexibility. However, their deployment in an outdoor environment is challenging due to the presence of wind gusts. The coordinated motion of a multi-sUAV system in the presence of wind disturbances is a challenging problem when considering collision avoidance (safety), scalability, and communication connectivity. Performing wind-agnostic motion planning for sUAVs may produce a sizeable cross-track error if the wind on the planned route leads to actuator saturation. In a multi-sUAV …

Nystrom Methods For High-Order Cq Solutions Of The Wave Equation In Two Dimensions, Erli Wind-Andersen

Dissertations

An investigation of high order Convolution Quadratures (CQ) methods for the solution of the wave equation in unbounded domains in two dimensions is presented. These rely on Nystrom discretizations for the solution of the ensemble of associated Laplace domain modified Helmholtz problems. Two classes of CQ discretizations are considered: one based on linear multistep methods and the other based on Runge-Kutta methods. Both are used in conjunction with Nystrom discretizations based on Alpert and QBX quadratures of Boundary Integral Equation (BIE) formulations of the Laplace domain Helmholtz problems with complex wavenumbers. CQ in conjunction with BIE is an excellent candidate …

Assessing Structural And Functional Brain Alterations And Work-Related Fatigue In Non-Hyposmic And Hyposmic Covid-19 Survivors, Rakibul Hafiz

Dissertations

In the year 2019, life began to change at the advent of a global pandemic caused by the novel coronavirus. Mask mandates and mass vaccinations have mitigated the effects significantly, yet cases keep rising with new variants, especially, in densely populated countries, like India. Recent neuroimaging evidence shows the virus can attack the central nervous system (CNS). However, exactly which brain regions undergo structural and functional changes remain largely unknown. Many patients experience 'loss of/reduced sense of smell' (i.e., hyposmic) and an alarming number of survivors develop persistent symptoms ('long-COVID') for several months after initial infection. Fatigue is the most …

Private Information Retrieval And Function Computation For Noncolluding Coded Databases, Sarah A. Obead

Dissertations

The rapid development of information and communication technologies has motivated many data-centric paradigms such as big data and cloud computing. The resulting paradigmatic shift to cloud/network-centric applications and the accessibility of information over public networking platforms has brought information privacy to the focal point of current research challenges. Motivated by the emerging privacy concerns, the problem of private information retrieval (PIR), a standard problem of information privacy that originated in theoretical computer science, has recently attracted much attention in the information theory and coding communities. The goal of PIR is to allow a user to download a message from a …

Rechargeable Multi-Cell Battery, Wei Qiao, Taesic Kim, Liyan Qu

Department of Electrical and Computer Engineering: Faculty Publications

A method for power management of a multi - cell battery includes identifying a desired power value and voltage value , determining a battery voltage value and a battery current value for a battery , determining a number of battery banks from a plurality of battery banks to use for the battery , where each battery bank includes one or more battery cells ( or battery modules ) , checking availability of each of the one or more battery cells ( or battery modules ) , selecting one or more battery banks from the plurality of battery banks , where …